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Background. Chemoradiotherapy has demonstrated efficacy in esophageal cancer but rarely is curative. To improve local control and decrease metastases, a 7-month regimen was used with standard-dose radiotherapy (RT), cisplatin (DDP), and continuous infusion (CI) 5-fluorouracil (5-FU) in patients with locoregional squamous/adenocarcinoma of the esophagus. Methods. Initial treatment consisted of RT to the esophagus (4000-5000 cGy) for 5-6 weeks, CI 5-FU (300 mg/[m.sup.2]/day) concurrent with RT, and DDP (25 mg/[m.sup.2]/ day X 3) for Days 1-3 and 21-23. Two monthly cycles of DDP (75 mg/[m.sup.2] Day 1) and 5-FU (300 mg/[m.sup.2] X 21 days) followed. Patients were restaged with endoscopy and computed tomography scan. Patients without evidence of residual disease received three more cycles of chemotherapy CT): those with persistent tumor underwent esophagectomy or additional CT/RT, and those with disease progress ion were offered alternative CT. Results. From December 1987 to September 1991, 18 men and 8 women, including 2 with adenocarcinoma, were eligible for inclusion in the study. All were evaluable for toxicity and response. The median age was 61.5 years (range, 50-80 years), the median pretreatment weight loss was 9 lbs, and the median serum albumin level was 4.3 mg%. Therapy was toxic; 19 patients were hospitalized for treatment-related esophagitis, thrombosis, or infection. Grade III and TV leucopenia were seen in 12 patients and 1 patient, respectively. One patient had Grade IV thrombocytopenia. Of 26 patients, 17 (65%) had no tumor on restaging. Five patients had recurrences in the esophagus (1), liver (3), and lung (2). Three patients had second neoplasms. The median survival was 24 months. Conclusion. This treatment regimen provides high frequency of local tumor resolution, but with significant toxicity. Cancer 1994; 74:1217-24. Key words: esophageal cancer, chemoradiotherapy.

Taurine, a nonessential amino acid (AA), is the most abundant free AA in the intracellular space. We measured plasma AA concentrations in 36 patients 7-28 d after intensive chemotherapy and/or radiation. Plasma taurine concentrations were uniformly low in all patients (20.0 [+ or -] 6.4 [mu]mol/L, L, x [+ or -] SD). Plasma taurine in 11 healthy volunteer control subjects was 45.0 [+ or -] 20.3 [mu]mol/L (P < 0.001). Other AA concentrations, specifically those of precursor AAs methionine and cystine, were normal. We prospectively measured plasma AA concentrations in 12 patients before starting and 6-10 d after completing intensive cytotoxic treatment. values before treatment were 37.2 [+ or -] 11.6, 109.6 [+ or -] 30.7, and 18.5 [+ or -] 4.8 for taurine, cystine, and methionine, respectively, and were 24.3 [+ or -] 6.0, 111.2 [+ or -] 23.8, and 24.0 [+ or -] 14.5 after treatment. Pretreatment plasma taurine correlated directly with the magnitude of decrease in plasma taurine during cytotoxic treatment (n = 12, 4 = 0.85, P < 0.01). Intensive cytotoxic chemotherapy and/or radiation leads to a reduction in plasma taurine concentrations without any change in its precursor AAs, methionine and cystine. The clinical relevance of plasma taurine depletion will need further study.

Animal and epidemiologic studies have raised hopes that effective chemoprevention of colorectal cancer in very high-risk patients may be possible in the future, but at present, the only established effective way to prevent colorectal cancer in very high-risk patients is colectomy. Advances in surgical techniques, improvements in stomal appliances, and medical advances in dealing with complications of colorectal surgery (such as impotence) have contributed to substantial improvements in the quality of life of patients who have had prophylactic colectomies.

Colonoscopy and endoscopic polypectomy are being utilized more frequently these days with the increased emphasis on the prevention, early detection, and treatment of colon cancer. Consequently, the problem of managing the malignant polyp is likely to be more frequently encountered. Many attempts have been made to clarify the management principles involved. Although the studies conducted have been imperfect in their design, the variety of information obtained from these studies is making the picture clearer. A more conservative approach is evolving. Many malignant polyps may be managed by endoscopic polypectomy alone. The criteria for which patients are to be managed in this fashion seem to be relatively simple ones, though technical problems with polypectomy performance and histologic evaluation are still frequently encountered. More carefully designed long-term studies are needed to create firm guidelines for the management of malignant polyps. Should screening and surveillance result in the discovery of earlier and more readily treatable forms of invasive colon cancer, endoscopic polypectomy will most certainly be a cornerstone of their treatment.

The most common presentation of colorectal carcinoma is in the symptomatic patient, most often with complaints of rectal bleeding, abdominal pain, or change in bowel habits. Symptomatic patients often have advanced disease and, because surgical resection is the only effective therapy at present, their chance for cure is poor. Until effective treatment is available, therefore, we must identify patients at high risk for lifelong screening. In addition, more effective means of surveillance of the general population need to be developed in order to diagnose patients at risk for sporadic colorectal cancer, given that this represents the majority of patients with disease. Tumor markers also would be useful to find residual disease while it is still resectable in patients who have undergone surgery for curative resection.

1. Amino acid uptake in vitroby jejunal mucosa was stimulated by the addition of adenosine cyclic 3′:5′-monophosphate (cyclic AMP), dibutyryl cyclic AMP, theophylline, and cholera toxin. This stimulation appeared to be specific for neutral and dibasic amino acids, since the uptake of iminoamino acids and 3-O-methylglucose was unaffected.