Search

We evaluated the precision and accuracy of multilaboratory measurements for determining freely dissolved concentrations (C

Black carbons (BCs) dominate the sorption of many hydrophobic organic compounds (HOCs) in soils and sediments, thereby reducing the HOCs' mobilities and bioavailabilities. However, we do not have data for diverse HOCs' sorption to BC because it is time-consuming and labor-intensive to obtain isotherms on soot and other BCs. In this study, we developed a frontal analysis chromatographic method to investigate the adsorption of 21 organic compounds with diverse functional groups to NIST diesel soot. This method was precise and time-efficient, typically taking only a few hours to obtain an isotherm. Based on 102 soot-carbon normalized sorption coefficients (KsootC) acquired at different sorbate concentrations, a sorbate-activity-dependent polyparameter linear free-energy relationship was established: logKsootC = (3.74 ± 0.11)V + ((-0.35 ± 0.02)log ai)E + (-0.62 ± 0.10)A + (-3.35 ± 0.11)B + (-1.45 ± 0.09); (N = 102, R(2) = 0.96, SE = 0.18), where V, E, A, and B are the sorbate's McGowan's characteristic volume, excess molar refraction, and hydrogen acidity and basicity, respectively; and ai is the sorbate's aqueous activity reflecting the system's approach to saturation. The difference in dispersive interactions with the soot versus with the water was the dominant factor encouraging adsorption, and H-bonding interactions discouraged this process. Using this relationship, soot-water and sediment-water or soil-water adsorption coefficients of HOCs of interest (PAHs and PCBs) were estimated and compared with the results reported in the literature.

Pentachlorophenol (PCP), a general ionized chlorinated aromatic contaminant, was treated with Ni/Fe nanoparticles (NPs). An increase in the Ni/Fe dosage enhanced the removal of PCP. The most effective nickel percentage was 0.5%. Among the selected surfactants including carboxymethyl cellulose, Triton X-100, and cetyl trimethylammonium bromide (CTAB), CTAB markedly enhanced the removal of PCP by Ni/Fe. From removal kinetics, increased sorption of PCP onto Ni/Fe surfaces with CTAB was observed when compared to that without CTAB. This is the result of the small particle size of Ni/Fe-CTAB and the electrostatic interaction between an electronegative phenolate group of PCP and the electropositive Ni/Fe-CTAB. The increased sorption of PCP onto Ni/Fe surfaces by CTAB accelerated the reduction of PCP. In addition, with CTAB, the observed bulky and soft surface of Ni/Fe NPs allows enhanced electron transfer from the zerovalent iron core. The removal mechanism of PCP is dechlorination for Ni/Fe-CTAB but, for bare Ni/Fe, adsorption is mainly responsible for the removal. The dechlorination pathways of PCP with Ni/Fe-CTAB were investigated. The ortho position of chloride can be more easily reduced than other positions. Ni/Fe-CTAB NPs have a high potential to treat polychlorinated aromatics.

article To increase our understanding of the roles of black carbon (BC), a highly sorptive and recalcitrant material, we measuredBCconcentrationsand fluxesinmarineparticulateorganiccarbon(POC)outofthewatercolumninthe GulfofMaine(GoM),arepresentativecoastalareadownwindofimportantBCsourcesoftheNortheasternUnited States.Concentrationsranged fromb0.1 to 16 μg/L in the spring and late summer, typically contributing between 1and20%of thePOC.Water-columnexport fluxeswerenear10gBC/m 2 ∙yr.Theseobservationssuggestthat(a)up to 50% of the "molecularly uncharacterized" POC in this region's seawater is combustion-derived BC, and (b) the "bioavailabilities" of hydrophobic pollutants like polycyclic aromatic hydrocarbons (PAHs) would be influenced substantially by sorption to BC. The observed BC spatial distributions implythat a large part of the BC was carried offshore by wind and that much of it is accumulated in the coastal sediments. On a global scale, these results suggest the GoM and other coastal areas with similar BC loadings accumulate significant amounts of highly recalcitrant organic carbon that remineralizes on geological time scales in the world's oceans.

Background Laparoscopic splenectomy has become the preferred surgical procedure for the management of idiopathic thrombocytopenic purpura (ITP). However, there studies have directly compared the incidence of recurrent ITP secondary to missed accessory spleens in open versus laparoscopic splenectomy. Methods Open and laparoscopic splenectomies performed for ITP at 4 sites over 18 years were analyzed. The incidence of recurrent disease secondary to missed accessory spleens was compared between the open and laparoscopic splenectomy groups. Results A total of 105 splenectomies (54 open/51 laparoscopic) were performed. Accessory spleens were identified in 6 laparoscopic and 6 open cases (P = .57). Recurrent disease occurred in 27.6% of open and 14.6% of laparoscopic cases (P = .222). There were no cases of recurrent ITP secondary to a missed accessory spleen in either group. Conclusions The incidence of missed accessory spleens causing recurrent disease is similar when splenectomy is performed either open or laparoscopically.

We demonstrate the use of polyethylene devices (PEDs) for assessing hydrophobic organic compounds (HOCs) in aquatic environments. Like semipermeable membrane devices (SPMDs) and solid-phase microextraction (SPME), PEDs passively accumulate HOCs in proportion to their freely dissolved concentrations. Polyethylene-water partition constants (K(PEW)S) were measured in the laboratory for eight polycyclic aromatic hydrocarbons (PAHs), five polychlorinated biphenyls (PCBs), and one polychlorinated dibenzop-dioxin (PCDD), and these were found to correlate with octanol-water partition constants (K(OW)s; log K(PEW) = 1.13 log K(OW) - 0.86, R2 = 0.89). Temperature and salinity dependencies of K(PEW) values for the HOCs tested were well predicted with excess enthalpies of solution in water and Setschenow constants, respectively. We also showed that standards, impregnated in the PED before deployment, can be used to correct for incomplete equilibrations. Using PEDs, we measured phenanthrene and pyrene at ng/L concentrations and 2,2',5,5'-tetrachlorobiphenyl at pg/L concentrations in Boston Harbor seawater, consistent with our findings using traditional procedures. PEDs are cheap and robust samplers, competent to accomplish in situ, time-averaged passive sampling with fast equilibration times (approximately days) and simplified laboratory analyses.

The solid-water distribution ratios (Kd values) of "native" PAHs, PCBs, and PCDDs in Boston and New York Harbor sediments were determined using small passive polyethylene samplers incubated for extended times in sediment-water suspensions. Observed solid-water distribution coefficients exceeded the corresponding f(oc)Koc products by 1-2 orders of magnitude. It was hypothesized that black carbon (fBC), measured in the Boston harbor sediment at about 0.6% and in the New York harbor sediment at about 0.3%, was responsible for the additional sorption. The overall partitioning was then attributed to absorption into the organic carbon and to adsorption onto the black carbon via Kd = f(oc)Koc + f(BC)K(BC)C(w)n-1 with Cw in microg/L. Predictions based on published Koc, K(BC), and n values for phenanthrene and pyrene showed good agreement with observed Kd,obs values. Thus, assuming this dual sorption model applied to the other native PAHs, PCBs, and PCDDs, black carbon-normalized adsorption coefficients, K(BC)S, were deduced forthese contaminants. Log K(BC) values correlated with sorbate hydrophobicity for PAHs in Boston harbor (log K(BC) approximately 0.83 log gamma w(sat) - 1.6; R2 = 0.99, N= 8). The inferred sorption to the sedimentary BC phase dominated the solid-water partitioning of these compound classes, and its inclusion in these sediments is necessary to make accurate estimates of the mobility and bioavailability of PAHs, PCBs, and PCDDs.

BACKGROUND: With the prevalence of antibiotic use, the diagnosis and management of Clostridium difficile disease requires assessment. METHODS: In a retrospective review, patients wits a positive culture, toxin, or both during 1 year were identified. Recent literature was reviewed. Results of culture and toxin, prior antibiotic use, antibiotic treatment history and cost were analyzed. RESULTS: Of 592 patients tested, 101 were positive ; 96 of 101 were available for review. Of thos positive tested for both, 45% were positive for toxin and culture. Sixty-two of 96 were treated with antibiotics; metronidazole was used in 90% Ten of 62 antibiotic treatments were changed (mean 3 days). Ten days of metronidazole is 1/200th the cost of vancomycin. CONCLUSIONS: In 55% of the positive cases in which culture and toxin were obtained, one test was negative. As metronidazole's efficacy and cost compares favorably with vancomycin, metronidazole is the drug of choice. Any changes made to antibiotic regimens occurred prior to the 6 days recommended in the literature.

Existing field data indicate that soot may significantly affect the environmental speciation of polycyclic aromatic hydrocarbons (PAHs). To expand hydrophobic partition models to include soot partitioning, we need to quantify fsc, the soot fraction of the solid matrix, and Ksc, the soot-carbon-normalized partition coefficient. To this end, we have developed a method that allows quantification of soot carbon in dilute and complex sedimentary matrices. Non-soot organic carbon is removed by thermal oxidation, and inorganic carbonates are removed by acidification, fol lowed by CHN elemental analysis of the residual soot carbon. The selectivity of the soot carbon method was confirmed in tests with matrices of known compostion. The soot quantification technique was applied to two sets of natural sediments, both previously analyzed for PAHs. The input histories of PAHs and soot recorded in a lacustrine sediment core followed the same general trends, and we thus infer a coupling between the two. Our measures of f...

Soil cores from the unsaturated zone of a waste site contaminated with benzene, toluene, ethylbenzene, and xylenes (BTEX) were flushed with water under conditions representative of those proposed for site remediation. With a laboratory column dispersivity of 1 cm, kinetic modeling of the breakthrough curves gave desorption rate constants of 0.01−0.1 h-1. Desorption studies in batch tests gave similar rates after accounting for differences in the solid-to-water ratios. The presence of nonaqueous phase liquid (NAPL) in one soil column was deduced from the flushing behavior of the xylenes, which showed increasing effluent concentration with increasing time. The amount of NAPL was estimated to be 5 mgNAPL/gsoil from the flushing of the most water-soluble constituent, benzene. This quantity of NAPL would increase the site's estimated flushing time by more than a factor of 5 over the case with only kinetically limited desorption of BTEX from soil particles.

Primary small intestinal malignant mesenchymal tumors are uncommon, and liposarcomas originating in the small bowel are extraordinarily rare. To the authors' best knowledge, no well-documented case of a primary small intestinal dedifferentiated well-differentiated liposarcoma (atypical lipomatous tumor) has been reported in the English language literature. A 72-year-old demented man presented with fatigue, weight loss, and anemia. He was discovered on gastrointestinal series with follow-through to have a 7-cm pedunculated, polypoid jejunal tumor with an adjacent 2.5-cm submucosal fatty mass. Microscopically, the smaller tumor was a well-differentiated liposarcoma (atypical lipomatous tumor) containing microscopic foci of benign smooth muscle. Based on classic light microscopic and immunohistochemical findings, the adjacent larger mass proved to be a moderately differentiated (Coindre grade II) leiomyosarcoma. We report the clinical, radiologic, and pathologic findings of this primary jejunal dedifferentiated liposarcoma. The possibly relevant association of myogenous elements in tumors showing adipocytic differentiation with leiomyosarcomatous dedifferentiation in the present case is also discussed.

The role of lymph node metastases in rectal cancer, their preoperative diagnosis, and their surgical and postoperative management are reviewed in this article. The results of traditional surgical approaches with and without adjuvant radiotherapy (XRT) and chemotherapy (CT) are detailed and contrasted with the results of mesorectal excision (MRE) in the high-risk patient with rectal cancer. A proposal is presented for a clinical trial to incorporate the improved surgical results of MRE on local, regional, and distant recurrence with selected use of XRT or CT.

Widespread use of petrochemicals often leads to accidental releases in aquatic environments, occasionally with disastrous results. We have developed a hydrophobic and oleophilic mesh that separates oil from water continuously in situ via capillary action, providing a means of recovering spilt oil from surface waters. Steel mesh is dip-coated in a xylene solution of low-density polyethylene, creating a hydrophobic surface with tunable roughness and opening size. The hydrophobic mesh allows oil to pass through the openings while preventing the concomitant passage of water. A bench-top prototype demonstrated the efficacy of such an oil recovery device and allowed us to quantify the factors governing the ability of the mesh to separate oil and water. Preliminary data analysis suggested that the oleophilic openings behave somewhat like capillary tubes: the oil flux is inversely proportional to oil viscosity, and directly proportional to the size of the mesh openings. An unpinned meniscus model was found to predict the water intrusion pressure successfully, which increased as the opening size decreased. The trade-off between water intrusion and oil flow rate suggests an optimal pore size for given oil properties and sea conditions.

It has recently been recognized that mobile colloids may affect the transport of contaminants in ground water. To determine the significance of this process, knowledge of both the total mobile load (dissolved + colloid-associated) and the dissolved concentration of a ground-water contaminant must be obtained. Additional information regarding mobile colloid characteristics and concentrations are required to predict accurately the fate and effects of contaminants at sites where significant quantities of colloids are found. To obtain this information, a sampling scheme has been designed and refined to collect mobile colloids while avoiding the inclusion of normally immobile subsurface and well-derived solids. The effectiveness of this sampling protocol was evaluated at a number of contaminated and pristine sites. The sampling results indicated that slow, prolonged pumping of ground water is much more effective at obtaining ground-water samples that represent in situ colloid populations than bailing. Bailed samples from a coal tar-contaminated site contained 10–100 times greater colloid concentrations and up to 750 times greater polycyclic aromatic hydrocarbon concentrations as were detected in slowly pumped samples. The sampling results also indicated that ground-water colloid concentrations should be monitored in the field to determine the adequacy of purging if colloid and colloid-associated contaminants are of interest. To avoid changes in the natural ground-water colloid population through precipitation or coagulation, in situ ground-water chemistry conditions must be preserved during sampling and storage. Samples collected for determination of the total mobile load of colloids and low-solubility contaminants must not be filtered because some mobile colloids are removed by this process. Finally, suggestions that mobile colloids are present in ground water at any particular site should be corroborated with auxiliary data, such as colloid levels in “background” wells, colloid-size distributions, ground-water geochemistry, and colloid surface characteristics.

Concern about world wide local recurrence rates for rectal cancer of 20-45%, together with anxiety at the recent proliferation of adjuvant therapies, led us to review the efficacy of total mesorectal excision (TME) with which no adjuvant therapy had been combined. Precise, sharp dissection is undertaken around the integral mesentery of the hind gut, which envelopes the entire mid rectum. This procedure adds to operative time and complications but has been claimed to eliminate virtually all locally recurrent disease after "curative" surgery. Independent analysis (J. K. M.) of prospective follow-up data extended over a 13-year interval (1978-91; mean 7·5 years). The actuarial local recurrence rate after curative anterior resection at 5 years is 4% (95% Cl 0-7·5%) and the overall recurrence rate is 18% (10-25%). 10-year figures are 4% (0-11%) and 19% (7-32%). In view of the high-risk classification used for the North Central Cancer Treatment Group (NCCTG), which has led to a trend to chemoradiotherapy, a similar group of high-risk Basingstoke cases was constructed for comparison purposes. This group included 135 consecutive Dukes' B (B2) and Dukes C cancer operations, both anterior resection and abdominal-perineal excision, for tumours below 12 cm from the anal verge. Results from TM E alone are substantially superior to the best reported (NCCTG) from conventional surgery plus radiotherapy or combination chemoradiotherapy: 5% local recurrence at 5 years compared with 25% and 13·5%, respectively; and 22% overall recurrence compared with 62·7% and 41·5%, respectively (Dukes' B cases [B2], 15%; Dukes' C cases, 32%). Meticulous TM E, which encompasses the whole field of tumour spread, can improve cure rates and reduce the variability of outcomes between surgeons. Far more genuine "cures" of rectal cancer are possible by surgery alone than have generally been believed or are currently accepted. Better surgical results are an essential background for the more selective use of adjuvant therapy in the future.

Assessing the hazard posed by sediments contaminated with hydrophobic organic compounds is difficult, because measuring the freely dissolved porewater concentrations of such low-solubility chemicals can be challenging, and estimating their sediment-water partition coefficients remains quite uncertain. We suggest that more accurate site assessments can be achieved by employing sampling devices in which polymers, with known polymer-water partition coefficients, are used to absorb the contaminants from the sediment. To demonstrate the current accuracy and limitations of this approach, we compared use of three polymers, polydimethylsiloxane, polyoxymethylene, and polyethylene, exposed to a single sediment in two modes, one in which they were exhaustively mixed (tumbled) with the sediment and the other in which they were simply inserted into a static bed (passive). Comparing porewater concentrations of specific polychlorinated biphenyl (PCB) congeners with results obtained using air bridges, we found the results for tumbled polymers agreed within 20%, and the passive sampling agreed within a factor of 2. In contrast, porewater estimates based on sediment concentrations normalized to f(OC)K(OC), the weight fraction of organic carbon times the organic-carbon normalized partition coefficient, averaged a factor of 7 too high. We also found good correlations of each polymer's uptake of the PCBs with bioaccumulation by the polychaete, Neanthes arenaceodentata. Future improvements of the passive sampling mode will require devices that equilibrate faster and/or have some means such as performance reference compounds to estimate mass transfer limitations for individual deployments.

To assess hydrophobic organic chemical (HOC) contamination in sediments, a method was developed using polyethylene (PE) passive samplers inserted directly in the intact sediment beds to measure freely dissolved HOC concentrations. Performance reference compounds (PRCs: d10-phenanthrene, d10-pyrene, and d12-chrysene), impregnated into the PE before use, allowed porewater concentrations to be deduced after exposure times much shorter than would be required for sampler equilibration (days instead of months). Three diverse sediments were used in the laboratory, and PE-deduced porewater concentrations of six native PAHs (phenanthrene, anthracene, fluoranthene, pyrene, benz(a)anthracene, and chrysene) matched results from air-bridge testing and from direct porewater extractions after correcting for colloid effects. PE strips, deployed from a boat in Boston Harbor, yielded concentrations that were like those measured in porewaters from a sediment core collected nearby. Notably, equilibrium partitioning (EqP) estimates were always much higher (up to 100x) than those measured using the other methods, suggesting the large inaccuracy of that approach. Hence, PE passive sampling appears to greatly improve the accuracy of assessing the hazards posed by compounds like PAHs in sediment beds.

We investigated groundwaters in the vicinity of a coal ash site near an electric generating station in the western U.S.A. The purpose of the study was to ascertain why fine particles or colloids appear in some subsurface water samples there. If such fine particles are merely introduced during bailing or pumping operations which suspend otherwise immobile soil colloids, we should exclude these particulate materials from the water samples before analysis intended to quantify what is moving through the aquifer. However, if the colloids were truly suspended and moving with the groundwater flow in situ, then we should includes their contribution to our assessment of the mobile loads. Application of very careful sampling techniques (slow pumping rates, no atmospheric exposure) did not cause the large quantities of colloids observed previously to disappear from well water in which they occured. Additionally, the same sampling procedures did not cause similar abundances of colloids to appear in waters collected from neighboring wells installed and developed in the same manner and in the same geologic strata. Thus we believe sampling artifacts do not explain the colloids' presence in the groundwater samples. On the other hand, the groundwater chemistry and the nature of the suspended colloids (size, composition) strongly suggest these fine particles were suspended and therefore moving with the groundwater flow. At wells exhibiting large amounts of suspended colloids (≈10–100 mg L −1 ), the water was enriched in CO 2 and depleted in O 2 relative to nearby locations. The colloids were typically between 0.1 and 2 μm in size and were primarily silicates. These results suggest to us that, where infiltrating water is percolating through a site that has been mixed with coal ash, the secondary carbonate mineral in the soils are being dissolved; removal of this cementing carbonate phase may consequently release soil silicate colloids to be carried in the flowing water. Such processes may enhance contaminant transport in groundwater by augmenting the pollutant load moving in the groundwater, and increasing the permeability of the porous medium to pollutant infiltration with water water and/or rainwater.

We have previously reported outcomes for all rectal cancers in BC in 1996. We found that our local recurrence rates and survival were suboptimal relative to current standards in recent literature.In this retrospective, population-based study, we report the influence of emergent presentation (obstruction, perforation, massive hemorrhage) on outcomes, types of surgical procedures and use of staging investigations, and use of adjuvant radiation and chemotherapy.There were 452 invasive adenocarcinomas of the rectum of which 45 were emergent and 407 nonemergent. Disease-specific survival at 4 years for emergent and nonemergent stage II cancers were 66% versus 80%, respectively, and for stage III cancers, 60% versus 73%, respectively (P0.04). Local recurrence rates at 4 years for emergent and nonemergent stage II cancers were 20% versus 15%, respectively, and for stage III cancers, 70% and 20%, respectively (P0.05). Surgical resection more frequently involved a stoma for emergent (60%) than for nonemergent (35%) cases (P0.01). Percent of patients having complete staging investigations were similar between emergent (42%) and nonemergent patients (39%). Adjuvant radiation was given in similar proportion to emergent (61%) and nonemergent (55%) patients. Adjuvant chemotherapy was given to a slightly higher proportion of emergent patients (63%) than nonemergent patients (43%).We conclude that outcome from rectal cancer management is worse for emergent than nonemergent presentation. Since there is no difference in use of staging investigations or adjuvant therapy, the difference in outcome is likely due to difference in surgical technique between emergent and nonemergent cases.

To determine if the breast imaging reporting and data system (BI-RADS) defines a group of patients with mammographic abnormalities in whom stereotactic core needle biopsy (SCNB) is appropriate.A blinded retrospective validation sample.A university-affiliated hospital.One hundred and nine consecutive patients who underwent fine-wire localization breast biopsy (FWLB) between Jan. 1, 1994, and June 1, 1999, with a known final pathological diagnosis.Blinded mammographic review and classification using the BI-RADS; review of corresponding pathological findings from FWLBs.Correlation of pathological findings with each BI-RADS category and analysis of the predictive value of clinical and radiologic features.BI-RADS findings were as follows: 0 malignant lesions in 10 category 3 cases, 18 malignant lesions (3 in situ, 15 invasive) in 68 category 4 cases and 24 malignant lesions (8 in situ and 16 invasive) in 31 category 5 cases. There was 1 malignant lesion in 22 category 4 cases in women younger than 50 years.SCNB should be applied to BI-RADS categories 3 and 4 (50 yr of age). FWLB should be reserved for category 4 (50 yr of age) and category 5 cases. This algorithm will reduce the morbidity and cost of breast biopsies in patients with nonpalpable mammographic abnormalities.

Purpose: Rectal cancer outcome depends on stage, technical aspects of surgical excision, and use of adjuvant chemoradiation. Here, we examine effects of positive resection margin and tumor distance from the anus in stage 2 and 3 cancers on 4-year disease-specific survival and recurrence. Methods: We reviewed all 495 rectal cancer patients registered in British Columbia in 1996. Results: There were 481 cases analyzed: 29 in situ, 134 stage 1, 107 stage 2, 100 stage 3, 83 stage 4, and 28 unknown stage. Survival was significantly affected by presence of positive resection margin in stage 2 and 3 cancers, P = 0.0001. Lower tumor distance from the anus for stage 2 and 3 cancers worsened survival, P = 0.0007, and overall recurrence, P =0.016, but not local recurrence, P = 0.11. Adjuvant postoperative combined radiation and chemotherapy in stage 2 and 3 cancers significantly improved survival, P = 0.070 and local recurrence, P = 0.018, but not overall recurrence, P = 0.19. Conclusions: Presence of positive resection margin and tumor distance from the anus affect survival, local recurrence, and overall recurrence. Adjuvant postoperative combined radiation and chemotherapy improved our outcomes. Our local recurrence rates for rectal cancers are worse than currently reported standards of less than 10%. Improved surgical excision and use of adjuvant preoperative radiation and chemotherapy may improve outcome.

Background: Short course neoadjuvant radiation has been shown to provide improved local control of rectal cancer in a clinical trial population even in the presence of standardized surgical techniques. However, this use of hypofractionated radiotherapy has been limited in North America owing to concerns over toxicity. Methods: Patients considered to have locally advanced rectal carcinoma received a radiation dose of 25 Gy given in five fractions to the posterior pelvis. Definitive surgery was then performed within 2 weeks. Retrospective analysis was performed Results: Sixty-three patients, of whom 60 were assessable, were treated with preoperative short course radiotherapy at the British Columbia Cancer Agency between 1991 and 1998, and 97% proceeded to R0 resection. Local recurrence developed in 3 patients (5%). Five-year actuarial overall and relapse-free survival rates for the group were 71% and 69%, respectively. The actuarial rates of relapse-free survival by stage at 5 years were stage 1 83%, stage II 75%, stage III 62%, and stage 4 0%. Eleven patients (18%) experienced a postoperative complication. Conclusion: Short course preoperative radiotherapy for operable rectal cancer can be delivered to a general population and produce high pelvic control rates with acceptable toxicity.

Before I begin, I would like to express my sincere thanks to the members of the Pacific Coast Surgical Association (PCSA) for the opportunity of serving as your president during the past year. I can honestly say that this is a high point in my surgical career, and I will be forever grateful for the honor that you have accorded me in electing me to act on your behalf. I am especially grateful for the confidence and friendship of the members of the Washington and British Columbia caucus who nominated me from within their ranks. As it turns out, I am the first Canadian so honored, and thus I feel it is fair to warn you that my remarks, and in fact this whole meeting, will have a distinctly Canadian flavor! In reviewing the history of Canadian participation in our association, as recorded in the Lyman Brewer Volumes, I discovered that the regionalization of our membership began in 1939 when British Columbia was added to Washington as region I. However, it was not until 1950 that the first Canadian member, Dr R. E. McKechnie, joined as an active member. It amused me, however, to see that Canadian participation began much earlier, when the Washington caucus adjourned to the Empress Hotel in Victoria for its scientific program, following surgical demonstrations known as wet clinics at the Mason Clinic in 1931. This hotel proved so popular that the meeting returned there in 1937 and again in 1947. The practice of holding wet clinics seems to have disappeared with the meeting of 1953, and the association then began with the more familiar paper sessions, which we continue to enjoy, with perhaps only occasional modifications, such as the introduction of posters and industrial exhibits more recently. It was particularly interesting to me to discover that one of my great surgical heroes was among the first Canadian members who joined in 1950, the year coincidentally that marked the founding of the University of British Columbia faculty of medicine. Dr H. Rocke Robertson was the first professor of surgery at the University of British Columbia and served as vice president of the PCSA in 1957. Dr Robertson was a distinguished academic surgeon with an impressive war record whose lifelong interest in surgical infection and trauma placed him in the vanguard of modern investigators in these important fields. He was recruited back to McGill University, his alma mater, in 1959 as professor of surgery, and it was in that capacity that I came under his influence as a first-year medical student. He impressed me with his gentlemanly manner, his encyclopedic knowledge of surgery, and his excellent teaching. During my 4 years as a student, he became a mentor to me and a role model whose breadth of interest and concern for patients struck me as unusual in the midst of many more archetypal surgical characters with whom we came in contact during our student days at McGill. His interest in surgical investigation spawned the University Surgical Clinic at the Montreal General Hospital, which became a model for other faculties in Canada and which supported the research that forms the basis of our endeavors to this day. This laboratory was adjacent to the surgical wards and was the site of studies in shock, pancreatitis, surgical infection, plastic and reconstructive surgery, and cardiac surgery. Each surgical resident was expected to spend at least 1 year in the laboratory as part of the residency program, and Dr Robertson, and later Dr Fraser Gurd who followed him as chief, always made a special effort to ask the research residents their opinions in the weighty discussions of surgical conditions at weekly rounds. This special status afforded those working in the laboratory made the prospect of the research year more attractive, and we all looked forward to the time when we would don the long white coats and join the ranks of the researchers for our year. Dr Robertson was so respected as an educator and as a leader that McGill University named him principal in 1963, and he was regrettably taken prematurely from the ranks of the surgical department at what I would judge to have been the height of his career in academic surgery. Because of his activities being moved to the East, he resigned from the PCSA in 1960. After a third career in government, consultation, and archival studies for the Royal College, he died in Ottawa on February 8, 1998. He was a consummate surgical professional. Since Dr Robertson, there have been 2 other Canadian vice presidents of the PCSA, including R. E. McKechnie on 2 occasions in 1962 and 1965 and the late Paul Jackson in 1977. Those of us Canadians who are fortunate enough to be elected to membership in this great association value our participation in its affairs, both at the caucus level with our colleagues in Washington and, of course, in the association as a whole. From the Department of Surgery, University of British Columbia, Vancouver. John K. MacFarlane, MD, FRCSC PRESIDENTIAL ADDRESS

Objective To examine the role of total mesorectal excision in the management of rectal cancer. Design A prospective consecutive case series. Setting A district hospital and referral center in Basingstoke, England. Patients Five hundred nineteen surgical patients with adenocarcinoma of the rectum treated for cure or palliation. Interventions Anterior resections (n=465) with low stapled anastomoses (407 total mesorectal excisions), abdominoperineal resections (n=37), Hartmann resections (n=10), local excisions (n=4), and laparotomy only (n=3). Preoperative radiotherapy was used in 49 patients (7 with abdominoperineal resections, 38 with anterior resections, 3 with Hartmann resections, and 1 with laparotomy). Main Outcome Measures Local recurrence and cancer-specific survival. Results Cancer-specific survival of all surgically treated patients was 68% at 5 years and 66% at 10 years. The local recurrence rate was 6% (95% confidence interval, 2%-10%) at 5 years and 8% (95% confidence interval, 2%-14%) at 10 years. In 405 "curative" resections, the local recurrence rate was 3% (95% confidence interval, 0%-5%) at 5 years and 4% (95% confidence interval, 0%-8%) at 10 years. Disease-free survival in this group was 80% at 5 years and 78% at 10 years. An analysis of histopathological risk factors for recurrence indicates only the Dukes stage, extramural vascular invasion, and tumor differentiation as variables in these results. Conclusions Rectal cancer can be cured by surgical therapy alone in 2 of 3 patients undergoing surgical excision in all stages and in 4 of 5 patients having curative resections. In future clinical trials of adjuvant chemotherapy and radiotherapy, strategies should incorporate total mesorectal excision as the surgical procedure of choice.

The stimulus to develop a wider pelvic dissection in the management of rectal cancer was initiated by the frustration of surgeons working in this area with the poor results of conventional operative approaches. Both local recurrence and death from metastatic disease seemed to be unacceptably high and it was hoped that using wider-field procedures would eliminate the last cancer cell, thus effecting a cure.

Purpose To determine the effect of extent of peritoneal contamination in enteric abscesses on final outcome and duration of percutaneous drainage. Patients and Methods Results were retrospectively reviewed for 11 patients with varying degrees of peritoneal contamination secondary to subacute bowel perforation who were primarily treated with percutaneous drainage. Stepwise linear regression analysis of duration of drainage was performed with use of patient age and immune status, the site of bowel perforation, and the number of peritoneal compartments involved in the resultant contamination as independent variables. Results In 10 of 11 patients (91%) treatment of the resultant intraperitoneal collections with percutaneous drainage was successful irrespective of the extent of peritoneal contamination. There was no correlation between duration of drainage and extext of peritoneal contamination but good correlation with patient age and site of bowel perforation ( r =0.82, P =.02). Conclusion In patients with enteric abscesses due to subacute bowel perforation, the duration of drainage and final outcome after percutaneous drainage are independent of the extent of peritoneal contamination.

Purpose The authors analyzed the safety and efficacy of trans-peritoneal percutaneous cholecystostomy (PC) in patients with acute cholecystitis. Patients and Methods Thirty-four consecutive patients underwent transperitoneal PC for treatment of acute cholecystitis. A trocar technique was used for placement of the drainage catheter. Results PC was technically successful in all patients. In 27 (79%) of 34 patients, symptoms of acute cholecystitis resolved within 7 days. Minor complications occurred in two patients (5%). Both patients developed a hematoma adjacent to the gallbladder; these resolved without treatment. No cases of bile leak or bile peritonitis occurred. Conclusion The transperitoneal route is safe and effective for PC.

Patients who have had ileogastrostomy for the treatment of morbid obesity require close, long-term follow-up. One concern in patients undergoing any form of intestinal bypass surgery is that of possible liver damage. To assess for possible liver damage in morbidly obese patients undergoing ileogastrostomy, we undertook a prospective study of liver biopsies in 12 consecutive patients. Preoperative and 2-year postoperative biopsies of the liver were planned. There were six liver biopsies available for comparison both pre- and post-operatively. The biopsies showed changes of fatty infiltration both pre- and post-operatively. There were no differences in the degree of fatty infiltration, or of other histological parameters which we measured. There were no cases of cirrhosis of the liver recorded.

Twelve patients (weight 107-178 kg and age range 19-43 years) were investigated following ileo-gastrostomy for morbid obesity. A number of variables were studied prospectively, pre- and postoperatively, to determine the cause of weight loss--previously attributed to malabsorption or decreased caloric intake. Weight loss of 10.9-36.5 kg, mean 22.9 kg, occurred. Three-day calorie counts demonstrated a postoperative decrease in daily caloric consumption of 320-3870, mean 1975 cal. Analysis of body compartment composition after derivation of lean body mass (from calculation of total body water with tritiated water) showed a mean decrease in adipose tissue of 17.7 kg. Postoperative weight loss, mainly fat, could not all be accounted for by decreased caloric consumption or steatorrhoea (72-h stool fat increased by a mean of 30 g). Pulmonary studies showed no significant change in respiratory quotient, but a large decrease in both postoperative utilization of oxygen and the production of carbon dioxide. This may indicate an alternate, anaerobic, energy cycle utilization. Other statistically significant variables included a large fall in cholesterol, LDH cholesterol and triglycerides, and smaller decrease in HDL cholesterol. Changes in gastro-intestinal (GI) hormones and cell counts in stomach and small intestine were also measured and will be reported later.

One hundred eighty-two fine needle aspirations (FNAs) of head and neck masses performed between the years 1981 and 1987 were studied retrospectively. Seventeen FNAs were unsatisfactory. Of the remaining 165, 148 (90%) were followed up with either surgery or clinical follow-up of at least 12 months' duration. Seventy-one of these aspirates were malignant. Fifty-six cases of metastatic carcinoma and 13 cases of lymphoma were diagnosed. The positive predictive value for metastatic carcinoma and lymphoma was 100%, and the sensitivities were 92% and 100%, respectively. For benign salivary gland lesions, the positive predictive value was 94%, whereas for malignant lesions it was 100%. One case of carcinoma ex-pleomorphic adenoma was missed by FNA. No complications were associated with FNA. We conclude that FNA is a safe and accurate technique, well suited to the in-office evaluation of neck masses of differing causes.

The bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) by the filter-feeding soft-shell clam Mya arenaria was evaluated at three sites near Boston (MA, USA) by assessing the chemical activities of those hydrophobic organic compounds (HOCs) in the sediment bed, water column, and organisms. Polyethylene samplers were deployed to measure the activities of HOCs in the water column. Sediment activities were assessed by normalizing concentrations with sediment-water sorption coefficient values, including adsorption to black carbon in addition to absorption by organic carbon. Likewise, both lipids and proteins were considered in biota-water partition coefficients used to estimate chemical activities in the animals. Chemical activities of PAHs in M. arenaria were substantially less than those of the corresponding bed sediments in which they lived. In contrast, chemical activities of PCBs in M. arenaria often were greater than or equal to activities in the corresponding bed sediments. Activities of PAHs, such those of pyrene, in the water column were undersaturated relative to the sediment. However, some PCBs, such as congener 52, had higher activities in the water column than in the sediment. Tissue activities of pyrene generally were in between the sediment and water column activities, whereas activity of PCB congener 52 was nearest to water column activities. These results suggest that attempts to estimate bioaccumulation by benthic organisms should include interactions with both the bed sediment and the water column.

Estradiol receptors were studied both qualitatively and quantitatively in 650 cases of breast cancer to obtain information on molecular forms and relationship with response to endocrine therapy. Cytosol estradiol receptor (ERC) was assayed by a charcoal method following incubations with 3H-estradiol and also by chromatography on Sephacryl columns. Results were classified as positive (10 fmoles/mg P and up), borderline (3-10 fmoles) and negative (0-3 fmoles). It was found that 44.6% of tumors were positive, 14.15% were borderline, and 41.2% were negative. Qualitatively, two major molecular forms of ERC were identified with molecular weights 31,000 and approximately 250,000. ERC level and response to endocrine therapy were correlated in a group of 52 patients. Response rate to hormonal therapy only was 59% in the ERC-positive, 28% in the borderline, and 9% in the ERC-negative group. Combination therapy, including endocrine manipulation, chemotherapy, and/or radiation improved response rates to 66% in the ERC-positive, 40% in the borderline, and 33% in the ERC-negative group. Defects in the translocation of the cytosol estradiol receptor (ERC)-estradiol complex to the nucleus could partly explain the failure of endocrine therapy in 40% of patients with significant ERC. To examine this possibility, 98 cases of breast cancer were examined for both ERC and nuclear translocation of estradiol (ERN). Nuclei were isolated from the low speed sediment and incubated with the ERC-3H-estradiol complex in the presence and absence of an estrogen competitor. After incubation, ERN was extracted from the nuclei and expressed as specifically bound estradiol, fmoles/mg DNA. Of 44 cases with significant ERC, nine had no ERN (20%). In the borderline group of 23 cases, eight had no ERN (34%), and of the 31 cases with zero or negligible ERC 27 had no ERN (87%). Results indicate that ERC-negative cases should be excluded from hormonal therapy and appear to benefit most from chemo- and/or radiation therapy. The absence of ERN in a significant proportion of ERC-positive cases probably contributes to the failure of hormonal manipulation in such patients. The results indicate that the determination of both ERC and ERN could improve the selection of patients for endocrine therapy.

The adherence to glass of human peripheral blood leukocytes (PBL) incubated with tumor antigen in vitro, is specifically inhibited if the PBL are sensitized to the antigen. The presence of leukocyte adherence inhibition (LAI) to tumor extracts indicates the presence of systemic antitumor immunity. By the tube leukocyte adherence inhibition assay (tube LAI), it was shown that 85% (191 of 223) Stage I and II, 45% (15 of 34) Stage III and 29% (30 of 103) Stage IV breast cancer patients had LAI reactivity. LAI responsiveness diminished with an increased tumor burden and most patients with advanced cancer exhibited no LAI reactivity. When LAI reactivity was monitored for 1 to 6 months after surgery, 13 of 25 Stage I and II breast cancer patients were negative on the first repeat assay. In general, 7 months after mastectomy most patients clinically free of cancer showed no LAI reactivity. Of thirty-five patients tested between 7 and 18 months after mastectomy, 6 were positive and 4 of the positives had local recurrence. The phenomenon of tube LAI appears to be mediated by monocytes armed with cytophilic antitumor antibody. The serum of patients whose leukocytes responded in the tube LAI assay had free cytophilic antitumor antibody that "armed" or sensitized normal leukocytes to respond in the LAI assay. Serum arming paralleled leukocyte reactivity before and after surgery. Patients with advanced cancer whose leukocytes failed to react in the LAI assay had serum blocking factors (excess tumor antigen) that abrogated the LAI reactivity of leukocytes from reactive patients.

The present study was undertaken to evaluate the specificity of antitumor immunity to human lung cancer, measured by an in vitro assay–tube leukocyte adherence inhibition (LAI). We standardized and monitored the putative tumor antigen activity of the extracts by testing leukocytes from controls and patients with lung cancer in the Montreal General Hospital. A specific antitumor response to a lung cancer antigen was detected with coded leukocytes from 56% (20 out of 36) of patients with epidermoid lung cancer. By contrast, 4% (2 out of 53) of patients with inflammatory lung disease and none of 46 other patients with cancer metastatic to the lung or with other diagnoses had an LAI-positive result. The LAI response was inversely related to the extent of cancer: 80% (8 of 10) with Stage I, 66% (2 of 3) with Stage II, 54% (6 of 11) with localized Stage III, and 33% (4 of 12) with widespread Stage III were LAI positive. Leukocytes from patients with epidermoid, adenocarcinoma, or small cell lung cancer reacted to a common tumor antigen shared by extracts of epidermoid and small cell lung cancer. This study with coded samples from a remote hospital confirms the results of other investigators that the LAI measures an antitumor immune response to human organ-specific neoantigens.

The tube LAI assay measures accurately antitumor immunity in patients with early cancer but fails to detect up to 75% of patients with advanced cancer due to excess circulating organ-specific neoantigen (OSN). Substances such as prostaglandin E2 (PGE2) or aminophylline, which increase intracellular nucleotides in leukocytes of patients with advanced cancer reversed this nonreactivity and greatly increased the sensitivity of the assay without any loss of specificity. Antitumor immunity can now be detected in advanced cancer, and a combination of the two assays gives prognostic potential to the assay: a positive test with PGE2 and negative test without indicates the patient has a large tumor burden. The specificity of the assay for each cancer was high and in most instances was greater than or equal to 95%. The PGE2 stimulated assay retained the high specificity. The sensitivity of the regular tube assay was often low, 33-56% because of the many advanced cancer patients tested, whereas the PGE2 stimulated assay showed almost a two-fold increase in sensitivity, 67-93%. The diagnostic value of the assay was estimated by calculating the predictive value for different prevalences of cancer. It was found that at low prevalences of cancer as found in the general population, the assay had a low diagnostic value since few patients with a positive test would have the cancer tested for. With prevalences of cancer of 5% or greater as might be found in a tertiary care clinical setting, the assay would seem to have diagnostic value since one half or more patients with a positive test would have the cancer tested for. Most false positives, but not all, are found in patients who have lesions that are often considered to increase their risk for cancer: severe dysplasia of the breast, colon adenomas, chronic atrophic gastritis and chronic pancreatitis, suggesting that the assay predicts oncogenesis.

Tumor-specific immunity to carcinoma of the colon, pancreas and stomach was assayed by tube LAI. Cancers of the colon, pancreas and stomach, were shown to possess organ-type specific neoantigens. In 115 patients with colon cancer, 100%, 75%, 61% with Dukes' A, B and C cancer were LAI positive, respectively. Even a microfocus of in situ cancer in a colon adenoma was sufficient to stimulate measurable tumor-specific immunity in the host. In Dukes' D cancer, 25% of patients with widespread metastasis were positive, whereas 100% with solitary lesions were positive. Reactive leukocytes from patients with colon cancer did not react to extracts of normal bowel mucosa or villous adenoma from LAI-negative patients. Leukocytes from 19% (3 of 16) of patients with colon adenomas reacted to the extract of colon cancer but not normal colon mucosa. Moreover, the LAI-positive response of the patients with colon adenomas or colon cancer is directed to a colon cancer TSA which is linked to beta2-microglobulin. These studies suggest that some colon adenomas express TSA before morphological evidence of cancer. It is not known if the acquisition of a cell surface TSA is an irreversible step toward unrestrained growth and metastasis. In pancreatic cancer, 100% of patients with cancers less than 5 cm and without metastasis were LAI positive, whereas 29% were positive when the cancer was greater than 5 cm or had metastasized. In Patients with stomach cancer, 100% with Stage II and 46% with Stage III and IV cancer were LAI-positive. Leukocytes from patients with other GIT cancers and from patients with inflammatory bowel disease or pancreatitis did not react with extracts of colon, stomach or pancreatic cancer. Leukocytes from patients with metastatic cancer, usually did not react in the tube LAI assay because their surfaces were coated in vivo with TSA. LAI reactivity was present when CEA was not detectable and when CEA levels were elevated LAI activity was often absent. The present study suggests that the automated tube LAI shows sufficient promise to warrant studies to determine its efficacy for the diagnosis of GIT cancers.

Leukocytes from control subjects show some non-adherence to glass when incubated with extracts of cancer, however, when the cancer extracts are of similar protein concentrations, the leukocyte non-adherence is also similar. Likewise, leukocytes from patients with limited cancer when incubated with extracts of unrelated cancer show non-adherence that is equal to control subjects. When the leukocytes from patients with limited cancer are incubated with extracts of the sensitizing cancer, then the mean leukocyte non-adherence is significantly higher than control subjects. By contrast, the leukocytes from patients with metastatic cancer exhibit a mean leukocyte non-adherence similar to leukocytes from patients with limited cancer when incubated with the sensitizing or unrelated cancer extract. Hence, LAI-negative patients with metastatic cancer have no residual population of LAI-reactive cells. The LAI-reactivity of leukocytes was abrogated by preincubation with the sensitizing TSA either from solid tumour or isolated from serum. Moreover, the tumour antigen coat on the leukocytes from patients with metastatic cancer was removed by gentle trypsinization of the leukocytes surface which restored the monocyte's capacity to react with the sensitizing tumour antigen. Hence, the increased non-adherence to glass of leukocytes from patients with metastatic cancer results from the LAI reactive cells (monocytes) being coated in vivo with TSA. The non-adherence of leukocytes from patients with limited and metastatic cancer is induced by the binding of TSA to the monocyte's cell surface; in the former instance binding occurs in vitro and in the latter in vivo. The results indicate that in advanced cancer there is no decrease in the number of host cells responding to the cancer antigens; however, the TSA shed from the tumour and present in excess in the circulation abrogates the tumour-specific responses in vitro and perhaps in vivo.

In vitro antitumor immunity, measured by means of a tube leukocyte adherence inhibition (LAI) assay, was able to demonstrate early colorectal cancer in cases yet undiagnosed. Testing 106 patients attending a colonoscopy clinic, we found that nine of 15 (60%) patients with colorectal cancer were LAI-positive. The nine included: five of six with Dukes' A and B; one of two with Dukes' C; and three of seven with Dukes' D lesions. Of 58 patients without colon neoplasia, one had a positive test. By contrast, barium enema results were diagnostic for 13 of 15 (87%) cases and colonoscopy for 11 of 15 (73%). There were 32 colon polyps discovered by means of barium enema and colonoscopy. Of 13 adenomas removed, four had stimulated positive LAI responses. Of another 19 polyps not removed two incited positive LAI responses. Two patients with histories of recurrent adenomas were LAI-positive, though only one had a new polyp that could be detected by means of barium enema. For a procedure to be of diagnostic value for a given disease, sensitivity and specificity must be at least 1.0. If this sum is 2.0, the test is ideal. The sum of sensitivity and specificity for the tube LAI assay, barium enema, and colonoscopy were 1.58, 1.87, and 1.73, respectively, for colorectal cancer; 1.81, 2.0, and 2.0, respectively, for early colorectal cancer; and 1.42, 1.77, and 1.55 respectively, for advanced colorectal cancer. In this limited series of patients, the barium enema seems to be superior to the tube LAI assay for diagnosing colorectal cancer, but the difference in sensitivity and specificity is not statistically valid by the paired chi square test. The results of this study shows conclusively, that the tube LAI is of diagnostic value and suggest its use for evaluating suspected cases, especially early ones, of colorectal cancer.

A safe and convenient method of anaesthesia, utilizing standard laboratory apparatus, has been described for use in cardiopulmonary bypass procedures in calves. The technique evolved during early work on aortic valve xenograft replacements. The long-term results of the series will be reported in a subsequent publication.

The intensity of cortisol binding was measured in the cytosol fraction of the primary tumor obtained from 50 patients with stage I and II breast cancer. The state of cellular antitumor immunity of the same patients was investigated by the tube leucocyte adherence inhibition (LAI) test, performed with peripheral blood leucocytes 1–2 days preoperatively. It was found that the intensity of tumor cortisol binding correlates negatively with LAI values. Patients with high cortisol binding in their tumors have low LAI values, while low tumor cortisol binding is associated with higher antitumor immunity. The results suggest that high cortisol binding in the tumor might inhibit the tumor recognition process and/or the cellular immune defense mechanism and thus facilitate cancer development.

Sebaceous cell carcinoma of the parotid gland is a rare lesion. A review of the English literature reveals nine previously reported cases. Two cases are presented in which the tumor was originally diagnosed as mucoepidermoid carcinoma. Aggressive treatment of the recurrence, which was subsequently recognized as sebaceous cell carcinoma has resulted in apparent cure. Histologic features and possible histogenesis are discussed.

Volatile halogenated organic compounds synthesized by various industrial processes are troublesome pollutants because they are persistent in terrestrial ecosystems and because they may be present in sufficient quantities to alter the natural atmospheric cycles of the halogens. Certain of these compounds, including polybromomethanes and several previously unobserved alkyl monohalides and dihalides, appear to be natural products of the marine environment. A variety of temperate marine macroalgae (the brown algae Ascophyllum nodosum and Fucus vesiculosis, the green algae Enteromorpha linza and Ulva lacta, and the red alga Gigartina stellata) not only contain volatile halogenated organic compounds but also release them to seawater at rates of nanograms to micrograms of each compound per gram of dry algae per day. The macroalgae may be an important source of bromine-containing material released to the atmosphere.

Antitumor immunity assayed by tube leukocyte adherence inhibition (LAI) is suppressed during and for up to 1–3 weeks after surgery. The results of this study suggest that when cortisol is elevated above physiologic levels by the stress of surgery this has a marked suppressive effect on the LAI-reactive cell. Cortisol added to the in vitro tube LAI assay had a two-phase effect. Cortisol at concentrations about two-fold above physiologic levels inhibited the sensitization of the peripheral blood leukocytes with cytophilic IgG antitumor antibody; however, if the cell was already armed, the cortisol did not negate its LAI reactivity. Higher concentrations of cortisol had a direct inhibitory effect on the LAI-reactive cells' ability to react with tumor antigen whether or not the cells were armed. In addition, the in vivo elevation of cortisol by the administration of cortisone acetate to LAI-positive patients inhibited the LAI reactivity of their leukocytes. Stress-induced elevation of cortisol by surgery may have an adverse effect on resistance to tumor growth, and the extent of the immunodepression may be one of the variables in the difference in survival of patients with cancers with similar degrees of invasion.

Tumour-specific immunity to pancreatic tumour antigens, assayed by an automated tube leucocyte-adherence inhibition assay (L.A.I.), was detected in 3 of 3 patients with localised pancreatic cancer and 3 of 8 patients with more extensive pancreatic cancer. Leucocytes from pancreatic cancer patients with L.A.I. reactivity did not react to antigens of stomach, colon, or lung tumours; leucocytes from patients with stomach, colon, or lung cancer or inflammatory disease of the pancreas and bowel did not show L.A.I. reactivity to pancreatic tumour antigens.

One hundred and three women were examined independently for presymptomatic breast disease by two nurses and two surgeons who recorded physical findings and their recommendations for further clinical workup. Agreement between the observers beyond what would have been expected by chance was assessed by a new extension of the statistic κ which allows multi-level scales of measurement, more than two observers (not necessarily the same for each subject), and comparisons between and within subsets of observers. Agreement between nurses and between the nurse-surgeon pairs was not significantly better than would have been expected by chance. Agreement within surgeon pairs was only slightly better than chance (overall κ for physical findings and recommendations being 0.42 and 0.32 respectively). Agreement between surgeons was generally better for physical findings than for recommendations and was best for the finding of fibrocystic disease. Future studies to compare the performance of nurses or other allied health professionals with surgeons should, therefore, be designed to allow assessement of the reliability of the standard group.