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The treatment options for primary irresectable rectal cancers are discussed. Assessment of tumour stage is the first step for an appropriate choice of treatment. Following a diagnosis of rectal cancer, a vast array of diagnostic procedures is available to determine its stage, and thereby its best treatment options. From the many (new) diagnostic options the merits and drawbacks are discussed. If a diagnosis of irresectability is made, further treatment options should include radiotherapy in most cases, some aspects of timing and application, i.e. intra-operative treatment are discussed. Chemotherapy options are manifold, the results are discussed and some new options are explored.

Purpose: To evaluate the feasibility and pharmacology of intraperitoneal (IP) topotecan. Patients and methods: Fifteen patients with recurrent ovarian cancer in a phase I trial were treated with escalating IP topotecan doses (5–30 mg/m2) for pharmacokinetic analysis. Results: Dose limiting toxicity (DLT) was acute hypotension, chills and fever at the 30 mg/m2 dose level. Haematological toxicity and abdominal pain were mild for all dose levels studied. Pharmacokinetics: Peak plasma levels of total topotecan were reached at 2.7 ± 1.1 h after IP instillation. The apparent V ss was 69.9 ± 25.4 L/m2, plasma clearance 13.4 ± 2.5 L/h/m2 and plasma T1/2 3.7 ± 1.3 h. The plasma AUC was correlated with the dose (R = 0.95, P < 0.01). The plasma AUC ratio of lactone versus total topotecan (lactone + carboxy-forms) increased with the dose from 16% to 55%, (R = 0.84, P < 0.01). Peritoneal total topotecan was cleared from the peritoneal cavity at 0.4 ± 0.3 L/h.m2 with a T1/2 = 2.7 ± 1.7 h. The mean peritoneal/plasma AUC ratio for total topotecan was 54 ± 34. Conclusion: A substantial dose of topotecan can be delivered by the IP route, achieving cytotoxic plasma levels of topotecan, with acceptable toxicity. The recommended dose for further phase II trials is 20 mg/m2 IP, which enables combination with active doses of other cytotoxic drugs, in view of its limited myelotoxicity when given by this route. © 2001 Cancer Research Campaign http://www.bjcancer.com

The specificity and sensitivity of the nested reverse transcriptase polymerase chain reaction (RT-PCR) on tyrosinase was studied, for the detection of micrometastases of malignant melanoma. The specificity was assessed in the blood of six healthy donors, four patients with non-melanoma cancers of which one patient was treated with granulocyte-colony stimulating factor. Lymph nodes of nine patients without malignant melanoma were tested and four cell lines of various other tumours. Six of the nine non-melanoma lymph nodes were positive in this assay. The sensitivity was tested in a spike experiment in vitro, using a melanoma cell line. The detection limit was ten melanoma cells per 10(7) peripheral blood lymphocytes. (C) 2000 Cancer Research Campaign.

Purpose: To assess the effect of the addition of leucovorin to the combination of 5-fluorouracil (5-FU)-levamisole on recurrence risk and overall survival in patients after a resection with curative intent of a Dukes' C colon cancer. Patients and methods: Five hundred patients with Dukes' C colon cancer were randomly assigned to adjuvant treatment for one year with 5-fluorouracil (450 mg/m(2) i.v. weekly) and levamisole (150 mg p.o. every two weeks), the C-group or with leucovorin (20 mg/m(2) i.v.), 5-fluorouracil and levamisole, the L-group. The median follow-up for patients still alive is 36 months. Four patients were ineligible because of advanced disease at the time of randomisation. Results: Sixty percent of the patients have completed all courses of chemotherapy. Of the remaining 40% of the patients who did not complete one-year treatment with chemotherapy, 46% discontinued because of toxic and/or emotional reasons. They were equally divided over both treatment arms. The addition of leucovorin increased toxicity (especially mucositis and conjunctivitis) without a significant increase in treatment withdrawal. Five-year disease-free interval (C-group: 49%, L-group: 46%; log-rank test, P = 0.86) and overall survival (C-group: 55%, L-group: 59%, log-rank test: P = 0.96) were very similar in both treatment arms. Conclusions: The addition of low dose leucovorin to the combination of 5-fluorouracil and levamisole in a 12-month adjuvant therapy for curatively resected Dukes' C colon cancer patients does not improve disease-free interval nor overall survival. The addition of leucovorin to the combination of 5-FU-levamisole increases toxicity. Therefore leucovorin-5-FU-levamisole is not recommended in a 12 months adjuvant regime of Dukes' C colon cancer.

Reinfusion of autologous hematopoietic peripheral blood stem cells (PBSC) or bone marrow is often accompanied by flushing, dyspnea, abdominal cramping, nausea and diarrhea. These symptoms and the observation that they can be prevented by ondansetron, a selective 5-HT3 receptor antagonist, led to the assumption that these side-effects are due to infusion of free serotonin during the reinfusion of PBSC or bone marrow. Twenty-five patients with solid tumors received, after myeloblative chemotherapy, a total of 30 reinfusions of PBSC and/or bone marrow. In 17 patients, serotonin levels in the bags containing the PBSC were measured. In all patients, platelet serotonin levels were determined before and 1 h post-reinfusion. In addition, before and 24 h after reinfusion urine was collected for determination of 5-hydroxyindole acetic acid (5-HIAA) and serotonin concentrations. Mean (+/- s.d.) total serotonin concentration in the bags was 2404 +/- 1555 nmol/l. Mean total volume reinfused was 471 +/- 185 ml. After reinfusion, the mean (+/- s.d.) levels of serotonin in platelets in patients increased from 3.2 +/- 1.4 nm/10(9) at baseline to 3.8 +/- 2.0 nm/10(9) (P = 0.02). Neither 24 h urinary 5-HIAA nor serotonin levels were affected. These results indicate that reinfusion of PBSC or bone marrow is accompanied by substantial infusion of free serotonin, which might explain the observed side-effects and justify the use of 5-HT3 receptor antagonists as pre- medication for this procedure.

We conducted a phase I and pharmacokinetic study of the topoisomerase II catalytic inhibitor fostriecin. Fostriecin was administered intravenously over 60 min on days 1–5 at 4-week intervals. Dose was escalated from 2 mg m−2day−1to 20 mg m−2day−1in 20 patients. Drug pharmacokinetics was analysed with high performance liquid chromatography with UV-detection. Plasma collected during drug administration was tested in vitro for growth inhibition of a teniposide-resistant small-cell lung cancer (SCLC) cell line. The predominant toxicities were elevated liver transaminases (maximum common toxicity criteria (CTC) grade 4) and serum creatinine (maximum CTC grade 2). These showed only a limited increase with increasing doses, often recovered during drug administration and were fully reversible. Duration of elevated alanine–amino transferase (ALT) was dose-limiting in one patient at 20 mg m−2. Other frequent toxicities were grade 1–2 nausea/vomiting, fever and mild fatigue. Mean fostriecin plasma half-life was 0.36 h (initial; 95% CI, 0–0.76 h) and 1.51 h (terminal; 95% CI, 0.41–2.61 h). A metabolite, most probably dephosphorylated fostriecin, was detected in plasma and urine. No tumour responses were observed, but the plasma concentrations reached in the patients were insufficient to induce significant growth inhibition in vitro. The maximum tolerated dose (MTD) has not been reached, because drug supply was stopped at the 20 mg m−2dose level. However, further escalation seems possible and is warranted to achieve potentially effective drug levels. Fostriecin has a short plasma half-life and longer duration of infusion should be considered. © 1999 Cancer Research Campaign

Background: Developing reliable methods to test the T-cell system may be important in the treatment of colon cancer patients with 5-fluorouracil/levamisole. In a pilot study we explored whether DNCB (dinitrochlorobenzene) skin testing correlated with plasma levels of soluble inter leukin-2 receptor (sIL-2r) and soluble CD8 (sCD8) and, secondly, whether the application of DNCB had any influence on the production of sIL-2r and sCD8. Methods: In 10 patients with advanced colon cancer and in 10 healthy volunteers, plasma levels of sIL-2r and sCD8 were measured before and 10 days after the application of 2 mg DNCB on the inner side of the forearm. Results: As expected, colon cancer patients showed a depressed immune system compared to healthy volunteers (DNCB skin test: P = .005, sIL2r [medians 700 vs 295, P = .002], sCD8 [medians 158 vs 90, P = .03], M-W test). The plasma levels for sIL-2r and sCD8 were significantly lower in the skin-positive cases (P = .01 and P = .03, M-W test). However, a large overlap, in plasma levels could be observed between the two skin categories. DNCB had no influence on the production of sIL-2r and sCD8; median change skin-negative and skin-positive -10 vs +25, P = .14, respectively; 48 vs 0, P = .32 (M-W test). Conclusions: DNCB skin testing and plasma levels of sIL-2r and sCD8 seem to be equally useful in evaluating the T-cell system and can he used simultaneously.

The effect of oral etoposide on CA-125 serum levels was evaluated in 17 patients with epithelial ovarian cancer and progressive disease during, or relapsing after, prior chemotherapy. Only three patients had measurable lesions at extraperitoneal sites. Five had no measurable lesions. The oral etoposide dose was 50 mg b.d. for 7 days every 3 weeks, escalating to 10 or 14 days and continued until clinical progression. CA-125 after 4 courses was compared to baseline (CA-125 ratio). The rate of change of CA-125 (s, slope of the exponential regression curve) during the first 4 courses was compared to s over a similar period before treatment. One patient had a clinical partial response. Two other patients had a biochemical response (CA-125 ratio

Bile acids are probably important in colon carcinogenesis. Regional differences in bile acid metabolism within the colon were studied to illuminate the preferential distal occurrence of colon cancer in Western countries. Faeces (24 h) were collected for bile acid measurement from 25 patients with hemicolectomy (nine left and 16 right) and 17 adenoma patients with an intact colon (control subjects). Duodenal bile and cytolytic and alkaline phosphatase activity of faecal water were also studied. The median percentage of deoxycholic acid (DCA) was lower in the hemicolectomy groups [left 48% (range 38-57%), right 45% (2-62%) vs. control subjects 59% (38-70%), P

Fostriecin is a novel antitumor antibiotic. In vitro studies showed that fostriecin inhibits DNA topoisomerase II (Topo II) catalytic activity, protein phosphatases involved with cell-cycle control and histone phosphatases. The relative contribution of these mechanisms to the antitumor activity has not been elucidated, but Topo II inhibition seems to be the major mechanism of action at in vitro cytotoxic fostriecin levels. Tumor cell lines with decreased Topo II content showed similar or increased sensitivity to fostriecin, compared to the parent cell lines. The reduced-folate carrier is probably responsible for the cellular uptake of fostriecin. The possible clinical consequences of these in vitro observations are discussed.

Etoposide phosphate is a water-soluble prodrug of etoposide. It was expected that this prodrug could be used to overcome the solubility limitations and erratic bioavailability of oral etoposide. To investigate the possibility of prodrug conversion to etoposide within the gastrointestinal lumen, etoposide phosphate was dissolved in water and incubated with human gastric juice or human bile in vitro. Samples were collected during 150 min and analysed for etoposide concentration with high-performance liquid chromatography. Conversion of prodrug to etoposide during incubation with gastric juice was negligible. There was significant conversion during incubation with bile at pH 7-8. The percentage of prodrug converted to etoposide at pH 8 after 60 min was 78 +/- 18% (mean +/- S.D.) for a 0.1 mg ml(-1) prodrug solution and 36 +/- 26% for 0.5 mg ml(-1). At pH 7, after 60 min 22% of prodrug was converted to etoposide when incubated at 0.1 mg ml(-1) and 10% at 0.5 mg ml(-1). No conversion was found after inactivation of alkaline phosphate (AP) by overnight heating of bile at 65 degrees C or by the addition of disodium edetate to the bile. In conclusion, because of AP in bile, variable conversion of etoposide phosphate to etoposide can be expected within the intestinal lumen after oral administration. This could have important pharmacokinetic consequences.

This study describes the efficacy and toxicity of a combination regimen consisting of cyclophosphamide, vincristine (oncovin) and carboplatin (COC) for advanced seminoma on an outpatient basis. Twenty-seven patients (mean age 43 years, range 28-63 years) were classified as stage IIC (n = 5), stage IID (n = 12), stage III (n = 9) or stage IV (n = 1). Six had been treated with prior radiotherapy; elevated B-HCG and elevated LDH serum levels were observed in 15 and 25 patients respectively. Patients were treated with four cycles of 750 mg m(-2) cyclophosphamide intravenously (i.v.), 1.4 mg m(-2) vincristine i.v. (maximum 2 mg) and carboplatin adjusted to creatinine clearance. Cycles were given at 3 week intervals. The median dose of carboplatin administered was 400 mg m(-2) (range 300-450 mg m(-2)). Six patients [22%; 95% confidence interval (CI), 6-38%] achieved a complete response (CR), 19 (70%; 95% CI, 51-88%) a partial response and two (8%; 95% CI, 0-18%) showed only a response in tumour markers but not a reduction of retroperitoneal mass (NR). Post-chemotherapeutic masses were not removed surgically or irradiated. After a median Follow-up of 26 months (range 5-69 months), two patients have died, one from cardiac arrest 2 years after achieving CR, the other with relapsed seminoma 5 months after therapy. None of the other patients relapsed. Main toxicity was haematological, with 22 patients (81%) experiencing thrombocytopenia WHO grade III/IV and 27 (100%) leucocytopenia WHO grade III/IV, requiring dose reduction in five patients. Seven patients experienced granulocytopenic fever. Non-haematological toxicity was rare. Peripheral neuropathy grade I was observed in four patients and grade III in one. Haemorrhagic cystitis occurred once. In conclusion, despite considerable haematological toxicity, COC is feasible on an outpatient basis, even after prior radiotherapy, and is an effective regimen for advanced seminoma with only 1/27 treatment failures after a median follow-up of 26 months.

Sublines of the human small-cell lung carcinoma (SCLC) cell line GLC4 with acquired resistance to teniposide, amsacrine and mitoxantrone (GLC4/VM20x, GLC4/AM3x and GLC4/MIT60x, respectively) were derived to study the contribution of DNA topoisomerase II alpha and -beta (TopoII alpha and -beta) to resistance for TopoII-targeting drugs. The cell lines did not overexpress P-glycoprotein or the multidrug resistance-associated protein but were cross-resistant to other TopoII drugs. GLC4/VM20x showed a major decrease in TopoII alpha protein (54%; for all assays presented in this paper the GLC4 level was defined to be 100%) without reduction in TopoII beta protein; GLC4/AM3x showed only a major decrease in TopoII beta protein (to 18%) and not in TopoII alpha. In GLC4/MIT60x, the TopoII alpha and -beta protein levels were both decreased (TopoII alpha to 31%; TopoII beta protein was undetectable). The decrease in TopoII alpha protein in GLC4/VM20x and GLC4/MIT60x, was mediated by decreased TopoII alpha mRNA levels. Loss of TopoII alpha gene copies contributed to the mRNA decrease in these cell lines. Only in the GLC4/MIT60x cell line was an accumulation defect observed for the drug against which the cell line was made resistant. In conclusion, TopoII alpha and -beta levels were decreased differentially in the resistant cell lines, suggesting that resistance to these drugs may be mediated by a decrease in a specific isozyme. Images Figure 1 Figure 3

In order to examine changes in pulmonary function in patients with locally advanced non-small-cell lung cancer (NSCLC) before, during, and after standard radiotherapy or combined chemoradiotherapy, we conducted a prospective study involving patients with such cancer, who were treated with radiation alone or with concurrent radiation and carboplatin from October 1992 to February 1994 at the University Hospital in Groningen, the Netherlands. Thirty-five patients were treated. Two patients were excluded because of pulmonary emphysema. Pretreatment values of TLC, VC, the gas-transfer coefficient (Kco), the pulmonary diffusing membrane factor (Dm), and pulmonary capillary blood volume (Vcap) were lower than in normal subjects and patients with chemotherapy-naive germ-cell carcinoma who had a similar pulmonary tumor load as the result of hematogenous metastases. The NSCLC patients' reduced Kco was explained by a decrease in Dm, a measure of alveolar-capillary membrane disturbance, and a similar decrease in Vcap. Pretreatment TLC did not correlate with Vcap or Dm, indicating extra- rather than intrapulmonary vascular and lymphatic obstruction as an explanation for the reduced Vcap and Dm. Locally advanced NSCLC was treated with radiation (n = 16) or combined continuous carboplatin infusion and radiation (n = 17). No changes in TLC, VC, Kco, Dm, or Vcap were observed during and 2 wk after the end of either treatment, nor were any differences in pulmonary function observed with the two treatments, indicating an absence of additional acute pulmonary toxicity caused by continuously infused carboplatin in this patient group.(ABSTRACT TRUNCATED AT 250 WORDS)

PURPOSE To evaluate the safety, tolerability, and efficacy of varying doses of recombinant human interleukin-6 (rhIL-6) after chemotherapy. PATIENTS AND METHODS In this phase I/II study, 19 breast (stage III to IV) or non-small-cell lung cancer (NSCLC) patients received mitoxantrone (10 mg/m2) and thiotepa (40 mg/m2) every 3 weeks, followed by rhIL-6 subcutaneously (days 5 to 15) at six dose levels: 0.5, 1.0, 2.5, 5.0, 10.0, and 20.0 micrograms/kg/d body weight/d (micrograms/kg/d). rhIL-6 was increased to the next level in the individual patient in case of incomplete bone marrow recovery (leukocyte count < 3 x 10(9)/L and/or platelet count < 100 x 10(9)/L at day 22) and/or platelet nadir less than 25 x 10(9)/L in two consecutive cycles. RESULTS Flu-like symptoms were observed in most of the patients. Nausea and vomiting were reported in seven of 48 and 19 of 48 cycles, respectively. Dose-limiting toxicity at 20.0 micrograms/kg/d of rhIL-6 consisted of World Health Organization (WHO) grade 3 to 4 flu-like symptoms, nausea, and vomiting. Platelet recovery was faster in cycle 1 at 10.0 and 20.0 micrograms/kg/d of rhIL-6 than at lower dose levels (P < .05); thrombocytopenia grade 4 was observed at most levels. However, only two patients needed platelet transfusions (1.0 and 2.5 micrograms/kg/d rhIL-6). rhIL-6 effects on leukocytes were not dose-related, with a trend for the neutrophil nadir to increase with rhIL-6 up to 10 micrograms/kg/d. rhIL-6 dose escalation did not affect hematologic parameters and chemotherapy cycle duration. Hemoglobin (P < .001) and cholesterol (P < .05) levels decreased, while acute-phase proteins increased. CONCLUSION rhIL-6 following chemotherapy is tolerable up to 10 micrograms/kg/d; flu-like symptoms and nausea were dose-limiting at 20 micrograms/kg/d. Platelet nadir did not differ for the various rhIL-6 doses. However, a faster platelet recovery was observed at 10.0 and 20.0 micrograms/kg/d of rhIL-6.

Initial studies have shown that recombinant human interleukin-6 (rhIL- 6) induces anemia. Until now, the pathophysiologic mechanism of this induced anemia has been unknown. To unravel the underlying mechanism, we examined 15 cancer patients receiving rhIL-6 as an antitumor immunotherapy in a phase II study. rhIL-6 was administered subcutaneously at 150 micrograms once daily for 6 consecutive weeks. Various hematologic and biochemical parameters were measured weekly during rhIL-6 treatment and 4 weeks after rhIL-6 discontinuation. To determine plasma volume and red blood cell (RBC) volume, radioisotope dilution assays with labeled autologous RBCs and with human serum albumin were performed before rhIL-6 administration and on day 8 of rhIL-6 therapy. Hemoglobin levels decreased (mean change +/- SE) 7% +/- 1.5% within 3 days after the start of rhIL-6 therapy (P < .0001) and 19% +/- 2% at week 4. Levels had normalized at follow-up. The plasma volume increased 18% +/- 5% during the first week of rhIL-6 administration (P < .003), whereas RBC volume remained unaffected. The mean RBC corpuscular volume remained unchanged for 2 weeks and then began to decrease slowly, reaching its nadir at week 6 (5% +/- 1%; P < .01). Serum iron levels decreased 65% +/- 12% at week 4 (P < .002) and then returned to initial baseline values. Erythropoietin levels increased rapidly up to 68% at week 3 (P < .0001) and had normalized 4 weeks after rhIL-6 therapy. Levels of serum albumin, prealbumin, and transferrin decreased (P < .0001, P < .003, and P < .0001, respectively), whereas levels of serum amyloid A (P < .003), C-reactive protein, haptoglobin, and alpha-1-antitrypsin (P < .0001) increased during rhIL-6 treatment. All levels returned to pretreatment values after discontinuation of rhIL-6. No alterations in reticulocyte counts, serum lactic dehydrogenase levels, and bilirubin levels were observed. A 6-week regimen of subcutaneous rhIL-6 results in a rapid dilution anemia, caused by an acute and significant increase in plasma volume and followed by hypoferremia. This anemia is reversible after the cessation of rhIL-6 treatment.

Initial studies have shown that recombinant human interleukin-6 (rhIL- 6) induces anemia. Until now, the pathophysiologic mechanism of this induced anemia has been unknown. To unravel the underlying mechanism, we examined 15 cancer patients receiving rhIL-6 as an antitumor immunotherapy in a phase II study. rhIL-6 was administered subcutaneously at 150 micrograms once daily for 6 consecutive weeks. Various hematologic and biochemical parameters were measured weekly during rhIL-6 treatment and 4 weeks after rhIL-6 discontinuation. To determine plasma volume and red blood cell (RBC) volume, radioisotope dilution assays with labeled autologous RBCs and with human serum albumin were performed before rhIL-6 administration and on day 8 of rhIL-6 therapy. Hemoglobin levels decreased (mean change +/- SE) 7% +/- 1.5% within 3 days after the start of rhIL-6 therapy (P < .0001) and 19% +/- 2% at week 4. Levels had normalized at follow-up. The plasma volume increased 18% +/- 5% during the first week of rhIL-6 administration (P < .003), whereas RBC volume remained unaffected. The mean RBC corpuscular volume remained unchanged for 2 weeks and then began to decrease slowly, reaching its nadir at week 6 (5% +/- 1%; P < .01). Serum iron levels decreased 65% +/- 12% at week 4 (P < .002) and then returned to initial baseline values. Erythropoietin levels increased rapidly up to 68% at week 3 (P < .0001) and had normalized 4 weeks after rhIL-6 therapy. Levels of serum albumin, prealbumin, and transferrin decreased (P < .0001, P < .003, and P < .0001, respectively), whereas levels of serum amyloid A (P < .003), C-reactive protein, haptoglobin, and alpha-1-antitrypsin (P < .0001) increased during rhIL-6 treatment. All levels returned to pretreatment values after discontinuation of rhIL-6. No alterations in reticulocyte counts, serum lactic dehydrogenase levels, and bilirubin levels were observed. A 6-week regimen of subcutaneous rhIL-6 results in a rapid dilution anemia, caused by an acute and significant increase in plasma volume and followed by hypoferremia. This anemia is reversible after the cessation of rhIL-6 treatment.

In phase I studies, lobaplatin showed activity in ovarian cancer patients pretreated with platinum. A phase II trial with lobaplatin was performed in patients with refractory or relapsed ovarian cancer to define activity and pharmacokinetics. Twenty-two patients were treated with lobaplatin administered as an intravenous bolus every 4 weeks. Dependent on creatinine clearance (CRCL) patients received 30 or 50 mg m-2 lobaplatin as the starting dose. Twenty-two patients received 78 courses (median 3, range 1-6). In eight patients total platinum (TPt) in plasma and urine, free platinum (FPt) in plasma ultrafiltrate (both measured by atomic absorption spectrometry) and lobaplatin in plasma ultrafiltrate measured (by high-performance liquid chromatography) were measured. Toxicity was confined to mild nausea and vomiting, mild leucocytopenia (WHO grade 3 in 18% of the courses), and renal function-related thrombocytopenia (WHO grade 3/4 in 53% of the courses). A correlation was found between CRCL and reduction in platelet count (r = -0.77; P < 0.01). No renal toxicity was encountered. Five of 21 evaluable patients (24%) achieved a response (four complete remissions and one partial remission). Remissions occurred mainly in patients who relapsed more than 6 months after primary treatment. The median survival from start of lobaplatin treatment was 8 months. The mean areas under the curve (AUCs) were 4.2 +/- 0.5, 3.0 +/- 0.6, and 3.2 +/- 1.1 h mgl-1 for TPt, FPt and lobaplatin respectively. The free platinum fraction (FPt/TPt) was initially very high, indicating low protein binding. FPt was essentially present as intact lobaplatin. Four hours after infusion 54 +/- 5% and 24 h after infusion 74 +/- 3% of the lobaplatin dose was excreted in the urine. In conclusion, lobaplatin is a platinum compound with anti-tumour activity in patients with relapsed ovarian cancer, especially in those who have platinum-sensitive tumours. The main toxicity of lobaplatin is thrombocytopenia and its dose should be corrected according to renal function.

BW502U83, an arylmethylaminopropanediol (AMAP), showed to be partially cross-resistant in a P-glycoprotein-positive and in a P-glycoprotein-negative, doxorubicin-resistant cell line, while no cross-resistance was noticed in a cisplatin-resistant cell line. Interstrand cross-links were not observed, but BW502U83 induced extensive DNA strand breaks. In a feasibility study the effect of intra-arterially BW502U83 was tested. One patient with a hepatocellular carcinoma showed partial remission and signs of a tumor lysis syndrome, another patient with a hepatocellular carcinoma improved clinically. A patient with soft tissue sarcoma had stable disease. Transient increase in SGOT, SGPT and LDH were observed, but no systemic side effects.

The efficacy and toxicity of intraperitoneal (i.p.) cisplatin plus systemic etoposide were studied in 36 patients with small (2 cm) residual i.p. ovarian cancer after achieving a partial response to platinum-based, first-line chemotherapy. Treatment comprised 90 mg/m2 i.p. cisplatin with intravenous (i.v.) sodium thiosulphate (day 1) and 600-800 mg/m2 i.v. etoposide (days 1 and 2), every 4 weeks for four to six cycles. 7 patients achieved a pathological complete response (pCR), one a pathological partial response and 16 were clinically stable without evidence of disease. After a median follow-up of 13 months, the median progression-free survival (PFS) was 11 months (95% confidence interval 7-16 months). The actuarial PFS at 24 months is 22% (95% confidence interval 8-36%). Three of six relapses after achieving a pCR (50%) were sited i.p., and 9 of 14 other patients with disease progression (64%) had an i.p. relapse, indicating insufficient local efficacy. There was no renal toxicity, but grade 3-4 leucopenia occurred in 63% and grade 3-4 thrombocytopenia in 8% of cycles, while nausea, vomiting and complete alopecia were common. Although side-effects were acceptable, the efficacy of treatment with i.p. cisplatin plus i.v. etoposide is limited.

With the help of stem cell reinfusion and hematopoietic growth factors, it is possible to get up to a ten-fold dose increase for certain chemotherapeutic drugs. A number of reasons may have made high-dose chemotherapy less dangerous and therefore more acceptable in a more upfront treatment setting. One of these is the addition of peripheral stem cell harvest obtained after mobilization with a hematopoietic growth factor alone or after chemotherapy followed by a hematopoietic growth factor, which seems to result in a faster recovery of neutrophils and platelets compared to bone marrow reinfusion alone. The combination of various hematopoietic growth factors could potentially improve hematopoietic recovery of the high-dose chemotherapy regimen. The relevance of tumor cells sometimes present in the reinfused hematopoietic stem cells is as yet unknown. High-dose chemotherapy may be interesting for a number of solid tumors such as nonseminomatous testicular carcinoma, breast carcinoma in the metastatic and adjuvant setting, ovarian carcinoma, tumors of young adults such as Ewing sarcoma and small cell lung carcinoma. In patients with refractory nonseminomatous testicular cancer there have been a number of studies performed with high-dose chemotherapy showing a 15% complete and prolonged remission. For other tumor types and settings it will be necessary to perform randomized studies before firm conclusions can be drawn. For example, this is especially important for patients with breast carcinoma with more than three positive axillary lymph nodes. Preliminary data from various groups compared to historical controls treated with standard adjuvant chemotherapy show favorable results of adjuvant chemotherapy containing high-dose chemotherapy. Many relatively small nonrandomized studies are performed in various stages of disease for ovarian carcinoma. Although there are long-term survivors reported it is currently difficult to draw firm conclusions. The potentially safer therapy of high-dose chemotherapy may reveal in the near future the role of high-dose chemotherapy in solid tumors.

To define the toxicity profile of recombinant human interleukin-6 (rhIL- 6) and to study its effect on hematopoiesis, biochemical parameters and other cytokines, rhIL-6 was administered in a phase I-II study to 20 patients with breast carcinoma or nonsmall cell lung cancer. RhIL-6 doses were 0.5, 1.0, 2.5, 5.0, 10, and 20 micrograms/kg/d, with at least three patients per dose level. RhIL-6 was administered 24 hours by continuous intravenous infusion followed by subcutaneous (SC) administration for 6 days, partly on an outpatient basis. RhIL-6- related side effects were fever, headache, myalgia, and local erythema. Starting at 2.5 micrograms/kg/d, these side effects were compounded by nausea, reversible increase in liver enzymes, and anemia. Flu-like symptoms were controllable up to and including 10 micrograms rhIL- 6/kg/d with acetaminophen. RhIL-6 increased platelet counts with a decrease in mean platelet volume and increased leukocytes caused by neutrophil, monocyte, and lymphocyte increase, with an increase in T cells and natural killer cells at 1.0 and 2.5 micrograms rhIL-6/kg/d. The reversible anemia was characterized by a decrease in serum iron, and an increase in ferritin and erythropoietin without reticulocytosis. RhIL-6 reduced total cholesterol levels and a dose-related increase of C-reactive protein and serum amyloid A plasma levels was observed. Serum IL-6 levels were increased, especially at 10 and 20 micrograms/kg/d, whereas no change in IL-1 beta and tumor necrosis factor alpha levels was observed. RhIL-6 can be administered with controllable side effects in this setting, up to and including a SC dose of 10 micrograms/kg/d on an outpatient basis, and has a promising stimulating effect on leukopoiesis and thrombopoiesis.

Oral calcium supplementation is thought to be a useful interventional agent to decrease colon cancer risk. This is supposedly due, at least in part, to the binding of bile acids and fatty acids by calcium in the colon, thus prohibiting the damaging effects of these substances to the epithelium. To determine the effects of calcium supplementation on fecal fat excretion, 24 subjects kept a fat and calcium constant diet for one week and were supplemented with either 0, 2 or 4 g elemental calcium as calcium carbonate in a double-blind fashion. At the end of the week 72-hour feces was collected, and total fat, neutral fat, fatty acids and the ratio of polyunsaturated and saturated fatty acids (P/S ratio) were measured. Calcium dose-dependently increased the percentual excretion of total fat as related to fat intake: 6.8 +/- 0.9% during 0 g, 7.4 +/- 1.0% during 2 g and 10.2 +/- 1.4% during 4 g, r = 0.44, p = 0.03. This was due to increased fatty acid excretion, excretion of neutral fat was not affected, nor was the P/S ratio. It is concluded that calcium supplementation modestly increases fecal fatty acid excretion. No adverse metabolic effects are to be expected from this in case of long-term calcium supplementation in subjects at increased risk for colon cancer.

Taxol, a diterpene alkaloid isolated from the bark of Taxus brevifolia, has a unique mechanism of action. The drug promotes the formation of microtubule polymers in a cell, by reversibly and specifically binding the beta-subunit of tubulin. Taxol is administered intravenously by a 3-24-hour infusion at 3-week intervals. Myelosuppression, especially neutropenia, appears to be the dose limiting toxicity in solid tumours at 200-250 mg/m2. Furthermore, side effects such as sensory neurotoxicity (with typical numbness, tingling and painful paraesthesiae in the extremities), diarrhoea and alopecia appear frequently. Mucositis appears to be the non-haematological dose limiting side effect at 390 mg/m2 that has been determined in patients with leukaemia. Hypersensitivity reactions, which have been fatal in individual cases, might be schedule dependent. Furthermore, antiallergic prophylaxis must be given, although this precaution might not be considered to be fully protective. Phase I studies performed with combinations of taxol and cisplatin, doxorubicin or cyclophosphamide have indicated the feasibility of these regimens and show promise for future investigations. Addition of granulocyte-colony stimulating factor (G-CSF), aimed at modulating myelosuppressive toxicity, showed in Phase I studies that the taxol dose could be increased to 250 mg/m2, with peripheral neuropathy as the dose limiting toxicity. In Phase II studies, taxol has been shown to be effective, including producing complete tumour remission, in advanced drug refractory ovarian carcinoma (19%-36% response rate), previously treated patients with metastatic breast carcinoma (27%-62% response rate), advanced non-small lung cancer (21%-24% response rate), advanced small cell lung cancer (37% response rate) and advanced head and neck cancer (34% response rate).(ABSTRACT TRUNCATED AT 250 WORDS)

The multidrug resistance-associated protein (MRP) is a 180- to 195-kDa glycoprotein associated with multidrug resistance of human tumor cells. MRP is mainly located in the plasma membrane and it confers resistance by exporting natural product drugs out of the cell. Here we demonstrate that overexpression of the MRP gene in human cancer cells increases the ATP-dependent glutathione S-conjugate carrier activity in plasma membrane vesicles isolated from these cells. The glutathione S-conjugate export carrier is known to mediate excretion of bivalent anionic conjugates from mammalian cells and is thought to play a role in the elimination of conjugated xenobiotics. Our results suggest that MRP can cause multidrug resistance by promoting the export of drug modification products from cells and they shed light on the reported link between drug resistance and cellular glutathione and glutathione S-transferase levels.

We describe the results of clinical and (or) surgical staging used by the same surgeon to select a group of 41 patients with advanced rectal cancer for preoperative radiotherapy. Fifteen patients with resectable but advanced rectal cancer were subjected to a short course of radiotherapy (30 Gy in 10 days), immediately followed by resection. High dose preoperative radiotherapy (50–56 Gy in 5 weeks) was administered to 26 patients with borderline resectable or fixed cancer. Adequate resection of the tumour was possible in 21 of these 26 patients 4 weeks after the end of the radiotherapy. A total of 36 patients thus underwent resection after preoperative radiotherapy. No radiotherapy related acute or late morbidity was seen. On 31 December 1992 the results were investigated retrospectively. The median time since entering into the study was 87 months (range 27–141). During the follow-up, pelvic recurrence was detected in six patients; one patient had concomitant distant metastases. The local recurrence free survival at 5 years calculated by the Kaplan-Meier method was 72% (95% CI 58–85). Distant metastases without local recurrence developed in 11 patients. The calculated survival at 5 years was 45% (95% CI 30.5–59).

The importance of the ultrafilterable platinum (fPt) fraction of cisplatin (CDDP) and carboplatin (CBDCA) for cytotoxicity and myelotoxicity was studied in vitro. By incubating CDDP or CBDCA with fetal calf serum (PCS) various fractions of fPt were prepared and determined by atomic absorption spectroscopy. A relation of % fPt fraction and incubation time (h) of 87e-1123t(r = −0.99) and 101e-o.oo87t (r = −0.99) were determined for CDDP and CBDCA, respectively. Cytotoxicity in the human small cell lung carcinoma cell line GLC4 and fPt fraction were closely related for CDDP (r = 0.99) and for CBDCA r = 0.97). However, at a similar fPt fraction the concentrations inhibiting cell survival by 50% (IC50) of CBDCA exceeded that of CDDP by a factor of 10-18 with 4 h exposure and a factor of 5 with continuous exposure. Tested in the range of peak concentrations in plasma of patients and at a clinically relevant fPt fraction of 10%, CDDP was not toxic for human bone marrow cells in the CFU-GM assay, whereas it was toxic at fPt fractions of 50% and 90%. However, CBDCA was myelotoxic at a (clinically relevant) fPt fraction of 50%, and also at 75% and 90%. The use of different fPt fractions, produced by the incubation method described in this study, permits the study of platinum drugs in vitro while approximating in vivo conditions might be used to evaluate myelotoxicity of new platinum drugs prospectively. For CDDP and CBDCA the fraction fPt determines cytotoxicity on tumor cells, and their different fPt fraction in patients account at least partly for their difference in myelotoxicity.

The biotransformation activity of the mono-oxygenase enzyme, 7-ethoxycoumarin-O-deethylase (EOD), was investigated in the upper digestive tract of colon cancer patients, and compared with patients with and without neoplasia. The three groups studied comprised 23 control, 17 metastasized colon cancer and 16 metastasized breast cancer patients. EOD activity was determined by spectrofluorometry in duodenal biopsies obtained during gastroduodenoscopy. No correlation between the presence of colon or breast cancer and the level of EOD activity was observed. It was concluded that biotransformation enzymes can be easily determined in duodenal biopsies derived during. gastroduodenoscopy. The role of EOD in the biogenesis of colon cancer seems to be limited.

In an effort to reduce the risk of colorectal cancer development, oral calcium carbonate supplementation has been used in previous studies for the precipitation of cytotoxic bile acids and fatty acids. In human intervention trials its effect on mucosal hyperproliferation in the colorectum has not always been satisfactory. Because the complexation of calcium and bile acids requires the formation of calcium phosphate, we performed an intervention study in 14 healthy volunteers, giving them 1,500 mg calcium as Ca3(PO4)2 for 1 week. The effects of tricalcium phosphate on luminal and faecal parameters of cytolytic activity were evaluated before, during, and after calcium phosphate supplementation. The cytolytic activity of faecal water and intestinal alkaline phosphatase activity in faecal water were not affected by supplemental calcium phosphate. In duodenal bile, the proportion of cholic acid tended to increase, whereas that of chenodeoxycholic acid tended to decrease during calcium phosphate supplementation. Neither concentrations of total and individual faecal bile acids, nor that of faecal fat were affected during calcium phosphate supplementation. It is suggested that, although phosphate is involved in bile acid precipitation, phosphate competes for calcium in the binding of fatty acids. This might possibly explain the unchanged cytolytic potency of faecal water, and therefore does not make tricalcium phosphate a suitable calcium compound for dietary intervention.

Plasma sIl-2R and sCD8 levels of 12 patients with renal cell carcinoma were determined before and during subcutaneous rIl-2 therapy. Patients with a complete/partial remission showed a significantly stronger initial increase of sCD8 compared to patients with stable disease or tumour progression.

To study the effect of oral supplemental calcium on colonic epithelial proliferation, 17 adenomatous polyp patients received 1.5 g Ca2+ as calcium carbonate daily during 12 weeks, while on a calcium constant diet, based on the patients' habitual diet. Seven subsequently continued calcium supplementation for 9 months without dietary restrictions. Epithelial proliferation rate in colonic biopsies, expressed as labelling index (%), was determined with 5-bromodeoxyuridine and immunohistochemistry. Biopsies were taken from the midsigmoid at time of polyp excision and at the end of the intervention period. Median labelling index increased from 6.1% before to 8.7% after 12 weeks calcium (n = 17, P < 0.02). This was due to increased labelling in the basal third of the crypts (11.9 vs 16%), whereas labelling in mid and luminal compartments was not affected. Labelling index remained increased after 1 year calcium supplementation at 8.8%. Crypt length was not affected by calcium. These results are in contrast to those of others, who have shown a decrease of rectal epithelial proliferation during similar doses of calcium. Therefore, the effect of nutritional intervention on colonic epithelial proliferation should be studied in biopsies taken not only from the rectum, but also from more proximal parts of the colon. Caution with respect to large scale intervention studies with calcium in high risk groups is mandatory.

A phase I trial with continuous intravenous infusion of lobaplatin (D-19466; 1,2-diamminomethyl-cyclobutane-platinum (II)-lactate) for 72 h was performed to determine the maximum tolerated dose (MTD). Each patient received a single dose level, the total dose of lobaplatin ranged from 30 to 60 mg/m2/72 h every 4 weeks. Eleven patients enroled in this study and received a total of 30 courses of lobaplatin (median 2; range 1-6). Thrombo-cytopenia was the dose-limiting toxicity, it reached WHO grade III in three out of six patients at 45 mg/m2/72 h, and WHO grade IV in two out of two patients at 60 mg/m2/72 h. Leucocytopenia was mild, as was nausea and vomiting. Phlebitis at the infusion site was found in three patients. During this trial there were no signs of renal, neuro- or ototoxicity. One patient with ovarian cancer, pretreated with three different platinum complexes, achieved a partial response now lasting for longer than 6 months. In conclusion, thrombocytopenia is the dose-limiting toxicity of lobaplatin administered by 72 h continuous infusion. The recommended phase II dose for this regimen is 45 mg/m2/72 h every 4 weeks.

Piritrexim is a lipid-soluble antifolate which, like methotrexate, has a potent capacity to inhibit dihydrofolate reductase. We performed a multicentre phase 11 study with piritrexim in patients with locally advanced or metastatic breast cancer. Twenty-four patients of which sixteen had received prior chemotherapy, were initially treated with 25 mg piritrexim orally administered trice daily for four days, repeated weekly, with provision for dose escalation or reduction according to observed toxicity. Of twenty-one patients evaluable for tumour response, one patient achieved a partial response which lasted for 24 weeks. Three patients had stable disease during 12 weeks of treatment, seventeen had progressive disease. Piritrexim was generally well tolerated, in eighteen patients the dose could be escalated. Myelotoxicity was the most frequent observed toxicity of this piritrexim regimen. Leucopenia and thrombocytopenia grade 3/4 occurred in 38% of the patients sometime during treatment. Pharmacokinetic analysis of piritrexim in three patients during the first treatment cycle, revelaed peak levels 1 to 2 h after an oral dose, with a trend towards a higher peak plasma levels and AUCs on the fourth dosing day compared with the first dosing day. In conclusion, orally administered piritrexim appears to be a regimen with little activity in patients with locally advanced or metastatic breast carcinoma.

In 56 patients with disseminated or locally advanced breast cancer it was attempted to reach a state of no evidence of disease by a remission induction regime containing prednisone, 5-fluorouracil, methotrexate, doxorubicin and vincristine. If successful, patients received an intensification regimen consisting of cyclophosphamide (7 g/m2) and etoposide (1.5 g/m2) with autologous bone marrow reinfusion. The complete remission rate of the induction regimen was 52% and the partial remission rate 42%. 32 patients received the intensification regimen. Two toxic deaths occurred. The median time to disease progression in the group with disseminated disease was 15 months. After a median observation of 4 years, 11 out of 19 patients with locally advanced breast cancer were free of disease. It is concluded that this approach may lead to prolonged disease-free survival in patients with locally advanced breast cancer, but does not influence the survival in disseminated disease.

Inhibition of oncogenes represents a new strategy that might lead to a better understanding of the different steps involved in tumorigenesis and also to the development of new therapeutic approaches. Attempts have been made to interfere with gene expression by in situ generation of mRNA from recombinant vectors (antisense RNA) or by the exogenous introduction of synthetic oligonucleotides (antisense oligonucleotides). Antisense oligonucleotides can inhibit the expression of specific genes by blocking the translation after hybridization with the target mRNAs — the antisense strategy. Antisense oligonucleotides can also be targeted to specific sequences of the DNA double helix. This causes inhibition of transcription — the antigene strategy. Regulatory sequences involved in controlling the transcription of oncogenes are used as targets for this type of ‘antigene' oligonucleotide. Both strategies can be applied to control the oncogene expression of tumour cells in tissue culture, as exemplified in this review by myc antisense oligonucleotides. Recently the antisense strategy is moving into the area of clinical trials, aimed at curing chronic myelogenous leukaemia by ex vivo bone marrow purging. However, many difficulties have still to be overcome before the application of antisense oligonucleotides can be evaluated in the treatment of cancer.

The efficacy and toxicity of a combination of carboplatin and cyclophosphamide (CC) were studied in a group of 76 patients with advanced ovarian cancer. Progression-free (PFS) and overall survival were compared with a historical group of 65 patients treated with CAP-5 (cyclophosphamide, adriamycin, cisplatin). Subjective toxicity was compared by the measurement of TWiST, the Time Without Symptoms of Disease or Treatment. Of 75 evaluable patients treated with CC, 18 (24%) had a pathologically complete remission (pCR), and 31 (41%) a partial remission (PR). CC led to leukopenia grade III in 38% and grade IV in 3% of 421 treatment cycles. Thrombocytopenia grade III was seen after 7% and grade IV after 2% of cycles. Treatment delay occurred in 11.5% and dose reduction in 21% of cycles. Nephro- or neurotoxicity did not occur. After a median follow-up of 18 months, the median PFS was 24 months and the overall survival was 25 months. Median duration of TWiST was 22 versus 10 months after CAP-5 (P < 0.01). Compared with historical controls, treatment with CC is equivalent to CAP-5. It is free of nephro- and neurotoxicity, but is more myelosuppressive. Quality of life, measured by TWiST, is significantly better during CC. As a consequence of its equivalent efficacy, but lower subjective toxicity, carboplatin should replace cisplatin in treating patients with advanced ovarian cancer.

The chemical stability of the new anticancer platinum analogue 1,2-diaminomethyl-cyclobutane-platinum(II)-lactate (D19466) in infusion media was studied in an accelerated stability testing experiment with a selective HPLC-UV method. Variables were time, temperature, light, concentration, and infusion mixture. Mean reaction rate constants of decomposition were, respectively, 0.9555 *10−2, 2.127 *10−2, and 4.221 *10−2 hr−1 at 37, 56, and 66°C at a concentration of 200 mg/L in normal saline. From the Arrhenius equation, shelf lives (5% loss) at 4, 22, 37, and 121°C were, respectively, calculated to be 41.6, 13.2, 5.7, and 0.15 hr. Mean reaction rate constant in 5% dextrose was 3.106 * 10−2 hr−1 (200 mg/L; 56°C) and differed from that in normal saline (P 0.05). There was no influence of normal daylight on the rate of decomposition. It is recommended to prepare D19466 infusions in normal saline. Chemical stability is then maximal 12 hr at room temperature or 24 hr at 4°C. No protection against normal daylight is required. Sterilization by heat is not possible.

Malignant carcinoid tumours, islet cell tumours and medullary carcinomas of the thyroid are tumours with similar clinical features. In patients with unresectable or metastatic tumours leukocyte interferon (IFN) and recombinant human (rh) IFN have demonstrated efficacy. Twenty-four evaluable patients with progressive tumours were treated with 2.5 megaunits rh IFN alpha-2b, administered once daily subcutaneously, for a median duration of 7 months (range 0.5-37+). Two carcinoid patients demonstrated a response in tumour size, 80% showed stable disease (SD). Sixty percent of the carcinoid patients with elevated urinary 5-hydroxyindoleacetic (5-HIAA) levels reached a biochemical partial response of the urinary 5-HIAA levels (median duration 13.5 months). In the patients with an islet cell or medullary tumour and an elevated tumour marker, the marker did not further increase. Of the 12 carcinoid patients evaluable for a symptomatic response, ten (83%) experienced a relieve of symptoms. IFN alpha-2b dose reduction or discontinuation due to toxicity was necessary in three and ten patients, respectively. No neutralising IFN alpha-2b antibodies developed despite prolonged treatment. In conclusion, IFN alpha-2b had a beneficial effect in patients with progressive tumours, while long-term IFN alpha-2b treatment did not augment neutralising antibodies. In view of the IFN alpha-2b-related toxicity, administration of IFN alpha-2b on alternating days may be preferable.

Diet is a major determinant of colon cancer risk. Calcium may protect against colon cancer, presumably by binding cytotoxic bile acids and fatty acids. Numerous studies support this proposition. In subjects at risk for colon cancer oral calcium supplementation has been shown to reduce rectal epithelial proliferation rate, thereby supposedly decreasing cancer risk. In contrast to the original hypothesis that phosphate counteracts the effect of calcium, evidence has now been provided that phosphate is crucial for the intraluminal binding of bile acids in complexes of calcium, phosphate, and bile acids. Supplemental calcium has been shown to reduce the cytotoxic potential of fecal water, which is probably attributable to the profound effect of calcium on bile acid and fatty acid metabolism. However, some reservation with regard to the protective ability of calcium seems to be warranted as we found that oral calcium supplementation caused an increase in epithelial proliferation rate in the sigmoid of patients with adenomatous polyps. Further controlled studies evaluating the effects of calcium on the epithelium of different parts of the colon should now be performed.

The cisplatin(CDDP)-resistant cell line GLC4-CDDP shows a variety of differences from the parent line GLC4. The aim of this study was to determine which of the observed changes correlated with the degree of resistance and was therefore relevant to the phenomenon of CDDP resistance. For these experiments we used cells of the sensitive hSCLC cell line GLC4 and the in vitro-acquired CDDP-resistant sublines GLC4-CDDP3 and GLC4-CDDP11, with a resistance factor (RF) of 3 and 11 respectively for CDDP and of 1.8 and 7.4 respectively for carboplatin. Carboplatin was used, in addition to CDDP in seeking relevant mechanisms. No consistency was found between the RF and the growth pattern or antigen expression, cellular volume, doubling time, cellular or nuclear platinum (Pt) content or the level of Pt-non-histone chromatin protein (NHCP) binding. A correlation was found between the RF and the level of glutathione (GSH), and a trend was found for the level of Pt-DNA binding, Pt-GG adduct content and the amount of interstrand cross-links (ISC). These changes might therefore be relevant for the development of resistance. These findings are compatible with a GSH-induced reduction of the amount of reactive Pt in the resistant cell, resulting in a lower net platination and toxic Pt-DNA adduct formation.

An increased colonic epithelial proliferation rate and an increase of the cryptal proliferative zone are probable markers of increased susceptibility to colonic cancer. In this study an immunohistochemical method using 5-bromo-deoxyuridine (BrdUrd) to measure the proliferation rate of colonic mucosa in vitro was used. Fresh endoscopic colonic biopsy specimens were incubated with BrdUrd and then processed for immunohistochemistry using a monoclonal antibody. Essential procedures with respect to the equal distribution of nuclei stained with BrdUrd in the biopsy specimens proved to be the cutting of the specimens before incubation and the use of a microwave oven at the beginning of incubation. The use of the procedure of the running average showed that 12 length cut crypts are sufficient to determine reliably the proliferation rate, expressed as the labelling index (LI). This was determined in the biopsy specimens of 10 subjects without organic colonic disease, eight patients with adenomatous colonic polyps, and in six patients with (recent) colonic carcinoma. Mean LI in the controls was significantly lower than in patients with colonic polyps and in those with colon cancer. It is concluded that this method is promising for screening persons at risk for colon cancer and will be of great potential in performing dietary intervention studies in these subjects.

We describe the presence of a large number of chromosome aberrations in lymphocytes of 50 patients with testicular cancer. These chromosomal aberrations were not only found in patients treated with chemotherapy but also in untreated patients or in patients after surgery alone. Our results suggest a role for genetic instability in the pathogenesis of testicular cancer. This instability might be a risk factor for the development of secondary malignancies.

Favourable pharmacokinetics of the prodrug are essential for successful HSVtk/ganciclovir (GCV) suicide gene therapy. [F-18] FHPG PET might be a suitable technique to assess the pharmacokinetics of the prodrug GCV noninvasively, provided that [F-18] FHPG mimics the behaviour of GCV. Since membrane transport is an important aspect of the pharmacokinetics of the prodrug, we investigated the cellular uptake mechanism of [F-18] FHPG in an HSVtk expressing C6 rat glioma cell line and in tumour- bearing rats. The nucleoside transport inhibitors dipyridamol, NBMPR and 2- chloroadenosine did not significantly affect the [F-18] FHPG uptake in vitro. Thymidine and uridine significantly decreased [F-18] FHPG uptake by 84 and 58%, respectively, but an enzyme assay revealed that this decline was due to inhibition of the HSVtk enzyme rather than membrane transport. Nucleobase transport inhibitors, thymine and adenine, caused a 58 and 55% decline in tracer uptake, respectively. In vivo, the ratio of [F-18] FHPG uptake in C6tk and C6 tumours decreased from 3.070.5 to 1.070.2 after infusion of adenine. Thus, in our tumour model, [F-18] FHPG transport exclusively occurred via purine nucleobase transport. In this respect, FHPG does not resemble GCV, which is predominantly taken up via the nucleoside transporter, but rather acyclovir, which is also taken up via the purine nucleobase carrier.

Chemotherapeutic efficacy is hampered by occurrence of drug resistance. Several mechanisms cause this phenomenon. A final common factor is the reduced capacity of resistant cells to go into apoptosis following treatment with DNA-damaging agents. It is therefore interesting to search for ways to facilitate this apoptotic process following use of chemotherapeutic drugs. The death receptor ligands tumor necrosis factor (TNF), FasL and TNF-related apoptosis-inducing ligand (TRAIL) might be interesting candidates as they are able to induce apoptosis by binding to their cell membrane receptors. Recombinant forms of these ligands potentiate chemotherapeutic drug effects in preclinical models. For the clinical application of TNF, FasL and TRAIL, it is of primary importance that their safety be guaranteed. RhTNF is the only ligand currently used in humans. However, systemic rhTNF has shown low antitumor activity and higher doses induce severe sepsis-like toxicity. Perfusion setting aimed at limb preservation with rhTNF plus melphalan is currently used in sarcoma patients. A number of options have been tested in the preclinical setting that might allow circumvention of TNF toxicity in the clinic. Systemic rhFasL administration in humans is not yet feasible because of observed severe liver toxicity in mice due to Fas-mediated apoptosis of hepatocytes. Measures to circumvent liver toxicity have not yet been exploited. Another option for using FasL in the clinic may be to identify an alternative route of administration. In the animal model, FasL appeared to be less toxic for the liver compared with anti-Fas antibodies when administered intraperitoneally. There are relatively nontoxic modulators of the Fas death pathway, such as interferon and nonsteroidal antiinflammatory drugs (NSAIDs), which might prove interesting in combination with chemotherapy. Finally, it may be possible to produce a modified FasL with a reduced toxicity profile. TRAIL, produced as soluble, zinc-stabilized rhTRAIL seems to be without preclinical toxicity. Agonistic DR4 and DR5 antibodies against their TRAIL death receptor are being studied as another potential clinical option to induce apoptosis. Due to the synergistic effect observed in the preclinical setting between death receptor ligands and other modulators of the death receptor pathways and chemotherapy, it may well be that this approach is especially of value in the clinic when combined with chemotherapy. Ideally, choices for specific (modified) death receptor ligands for the treatment of patients can be rationally made based on tumor characteristics.

Therapeutic angiogenesis constitutes an alternative treatment for patients with extensive tissue ischaemia in whom primary vascular reconstruction procedures are not feasible or have previously failed. At present vascular endothelial growth factor (VEGF) has been the most widely used angiogenic factor in experimental and human clinical trials. Early clinical data provide evidence that gene transfer of the VEGF gene can achieve beneficial angiogenesis, with minimal side-effects. Ongoing phase III clinical studies will reveal definitive efficacy.

Combinations of dacarbazine (DTIC) and other cytotoxic agents or alpha-interferon were given to 136 patients in five different regimens. The total response rate was 32% (95% confidence interval 24-40%); 13% had a complete remission. Female patients had a significantly higher chance of response than male patients: 46% vs 23%. There was also a difference in complete response rate: 25% vs 9%. The overall survival was 6 months; 8% of patients had a response of more than 6 months and 2% of more than 2 years. Although response rates vary among the various regimens described in the literature, the complete response rates are quite similar and the long-term disease-free survival of these combinations may be similar to that of dacarbazine alone.

Results are presented following 119 curative resections for rectal cancer performed on 47 women and 72 men. Throughout the study it was policy to remove part of the female genital tract when the rectal tumour impinged on the uterus and/or the posterior vaginal wall. After a median follow-up of 7·5 years, local recurrence occurred in three of 46 women and 15 of 71 men (P = 0·03). The survival rates at 5 years were 71 per cent for women (95 per cent confidence interval 56–83 per cent) and 60 per cent for men (95 per cent confidence interval 50–71 per cent) (P < 0·05). The risk for distant metastasis was comparable, suggesting an influence of local recurrence on survival. Reduction of the local recurrence rate coincides with the higher proportion of anterior extensions of surgery in women (19 of 47) than in men (two of 72).

Long-term peripheral blood counts and factors influencing long-term trilineage haematological recovery of consecutive patients in a single institution treated with high-dose chemotherapy (HDC) and ABMT or PSCT for solid tumours were examined. Patients with a relapse-free survival of >1 year were included in the analysis (n = 131), Peripheral blood counts were examined 6 months and yearly following transplantation. Median follow-up was 4.1 years (range 1-10+ years), Three years after transplantation 91% of patients had normal white blood counts (WBC), 94% normal haemoglobin (Hb) and 75% normal platelets. Trilineage recovery was complete in 70% (n = 83) at 3 years and 85% (n = 50) at 5 years, Recovery of Hb occurred before WBC and platelet recovery. Approximately 25% of patients displayed an elevated MCV throughout the follow-up period. These long-term results were independent of age, high-dose regimen, number of reinfused stem cells and stem cell source. Double (n = 12) vs single (n = 119) transplantations showed significantly slower trilineage recovery and higher MCV, No secondary graft failure, myelodysplasia or leukaemia was encountered. In conclusion, complete trilineage recovery after HDC followed by ABMT or PSCT occurs slowly. PSCT and ABMT are capable of maintaining long-term haematopoiesis, Slower recovery is seen after double transplantations. The results suggest lasting implications for bone marrow function after autologous transplantation.

The T cell receptor (TCR) is an heterodimeric protein on the cell membrane of cytotoxic T cells (CTLs). In CTLs TCRs mediate the recognition of target cells through interaction with specific, MHC class I presented peptides.As a model system to show proof of principle we chose the Jurkat/MA cell line and the HLA-A2.1 binding MAGE-3 derived peptide 271-279, as target specificity.We show that this cell line can be successfully transduced with the dicistronic retroviral vector (LZRS) containing cDNAs encoding for the complete alpha and beta chains of the selected TCR. Following retroviral transduction, Jurkat/MA cells do express the anti-MAGE-3 TCR on their membrane. The transduced TCR is functional as travoductants are successfully triggered, upon stimulation with T2 cells or MAGE-3+ melanoma cells loaded with the MAGE-3 peptide.We conclude that TCR gene transfer is possible and it represents a powerful therapeutic tool for the genetical modification of T calls of patients sullering from cancer.

Medical oncology is a relatively young, rapidly growing subspecialty of internal medicine. This discipline will increasingly fulfil a role in the multidisciplinary approach for cancer patients. The fact that the population is rapidly aging, makes it of relevance to train medical oncologists further in the treatment of elderly patients. The growing number of cancer survivors deserves also special attention in order to limit the frequency of long-term side effects. Apart from the classical function as a doctor who treats cancer patients with drugs, the medical oncologist will play an expanding role at the far ends of oncology, namely in prevention and palliative care. Basic sciences create a tremendous amount of new knowledge on cancer detection, behavior and rational drug design. An important task for the medical oncologist will be to translate this expertise to the clinical scenario. The expanding requirement of specific skills of medical oncologists in the next century is likely to cause a further subspecialization within medical oncology.