Corrigendum: Eastern Canadian Gastrointestinal Cancer Consensus Conference 2014.

[This corrects the article DOI: 10.3747/co.22.2603.].

Eastern Canadian Gastrointestinal Cancer Consensus Conference 2016.

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2016 was held in Montreal, Quebec, 5-7 February. Experts in radiation oncology, medical oncology, surgical oncology, and infectious diseases involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics: ■ Follow-up and survivorship of patients with resected colorectal cancer■ Indications for liver metastasectomy■ Treatment of oligometastases by stereotactic body radiation therapy■ Treatment of borderline resectable and unresectable pancreatic cancer■ Transarterial chemoembolization in hepatocellular carcinoma■ Infectious complications of antineoplastic agents.

Eastern Canadian Gastrointestinal Cancer Consensus Conference 2014.

The annual Eastern Canadian Colorectal Cancer Consensus Conference was held in Montreal, Quebec, 23-25 October 2014. Expert radiation, medical, and surgical oncologists and pathologists involved in the management of patients with gastrointestinal malignancies participated in presentations and discussions resulting in consensus statements on such hot topics as management of neuroendocrine tumours, advanced and metastatic pancreatic cancer, and metastatic colorectal cancer.

Bcl-2 is a useful prognostic marker in Dukes' B colon cancer.

BACKGROUND: Currently, the use of adjuvant therapy specifically in Dukes' B colon cancers is controversial, emphasizing the importance of identifying prognostic markers to select patients for such therapy. Bcl-2 plays an important role in apoptosis regulation of solid tumors, such as colon and breast cancer, and is normally expressed in the base of the colonic crypts. The purpose of this study is to determine whether or not bcl-2 expression can be used to predict survival in Dukes' B colon cancer patients. METHODS: Charts of 76 patients operated on at the Royal Victoria Hospital from 1986 to 1992 were reviewed. Bcl-2 staining was done with the avidin-biotin-peroxidase complex method using commercially available monoclonal bcl-2 antibodies. Two pathologists graded the intensity of bcl-2 staining on a scale of 0-3 and estimated the percentage of tumor cells staining positively (T-percent). Univariate and multiple regression of factors on overall survival (OS) and disease-free survival (DFS) was done with a Cox proportional hazards model and Kaplan-Meier survival curves. RESULTS: The mean age was 71.2 years, with 41 female and 35 male patients. Mean tumor size was 5.4 cm with tumor grades of 19 well, 52 moderate, and 5 poorly differentiated. Tumors expressing bcl-2 had a similar DFS (P = .14) but a significantly improved OS (P = .04) compared with the bcl-2 negative tumors. The risk ratio for DFS was 0.49 (95% CI, 0.19-1.26) and for OS was 0.35 (95% CI, 0.13-0.94). CONCLUSIONS: These data indicate that enhanced bcl-2 expression, specifically in Dukes' B colon carcinomas, is associated with improved survival. Thus, patients whose tumors do not express bcl-2 should be considered for adjuvant therapy.

Prognostic markers in resectable non-small cell lung cancer: a multivariate analysis.

OBJECTIVE: To identify the prognostic significance of certain clinical, cellular and immunologic markers in resectable non-small cell lung cancer (NSCLC). DESIGN: A cohort of patients with resectable NSCLC was prospectively followed up for 8 years (100% follow-up). SETTING: A university hospital in a large Canadian city. PATIENTS: One hundred and thirteen consecutive patients who underwent surgical resection of primary NSCLC. MAIN OUTCOME MEASURES: Presence of peritumoral B lymphocytes (identified with antibody to CD20) and T lymphocytes (antibody to CD43), along with tumour markers (carcinoembryonic antigen [CEA], keratin, cytokeratin, S-100 protein, vimentin, chromogranin) and other factors such as age, sex, cell type, American Joint Committee on Cancer (AJCC) stage, histologic grade, DNA ploidy and S-phase fraction were correlated with survival. RESULTS: The mean age of patients in the study was 66.0 years; 60% were male. Histologic types of the tumours were: adenocarcinoma 57 (50.4%), squamous cell 47 (41.6%), adenosquamous 6 (5.3%) and large cell 3 (2.6%). AJCC stages were: I 66 (58.4%), II 20 (17.7%) and III 27 (23.9%). Histologic grades were: I (well differentiated) 31 (27.4%), II 50 (44.2%), III 29 (25.7%) and IV 3 (2.6%). Survival was 85% at 1 year (95% confidence interval [CI] 76%-90%), 44% at 5 years (95% CI 34%-53%) and 34% at 10 years (95% CI 22%-46%). Multivariate analyses using the Cox proportional hazards model for survival confirmed AJCC stage (p < 0.001) in all histologic subtypes to be the strongest factor of independent prognostic significance. It also revealed the presence of CD20-stained B lymphocytes (p = 0.04) in the peritumoral region of all tumours to be a positive prognostic factor. This relation was especially strong for nonsquamous cell carcinomas (p < 0.001). For squamous cell carcinomas, the immunohistochemical presence of CEA was of marginally negative prognostic value (p = 0.04). DNA ploidy and a high S-phase fraction showed no evidence of prognostic value for stage I tumours, but for stages II and III tumours there was strong evidence of prognostic value (p < 0.001 jointly). The evidence for DNA ploidy was especially strong in stages II and III squamous cell tumours (p = 0.008), and for a high S-phase fraction was strongest in stages II and III nonsquamous cell tumours (p = 0.002). CONCLUSIONS: AJCC stage remains the most important prognostic indicator from a variety of clinical variables and tumour markers in postoperative patients with resectable NSCLC. For nonsquamous cell lung carcinomas, the presence of peritumoral B lymphocytes was strongly associated with improved survival, suggesting an important role for humoral mediated immunity.

Caspase-8-mediated intracellular acidification precedes mitochondrial dysfunction in somatostatin-induced apoptosis.

Activation of initiator and effector caspases, mitochondrial changes involving a reduction in its membrane potential and release of cytochrome c (cyt c) into the cytosol, are characteristic features of apoptosis. These changes are associated with cell acidification in some models of apoptosis. The hierarchical relationship between these events has, however, not been deciphered. We have shown that somatostatin (SST), acting via the Src homology 2 bearing tyrosine phosphatase SHP-1, exerts cytotoxic action in MCF-7 cells, and triggers cell acidification and apoptosis. We investigated the temporal sequence of apoptotic events linking caspase activation, acidification, and mitochondrial dysfunction in this system and report here that (i) SHP-1-mediated caspase-8 activation is required for SST-induced decrease in pH(i). (ii) Effector caspases are induced only when there is concomitant acidification. (iii) Decrease in pH(i) is necessary to induce reduction in mitochondrial membrane potential, cyt c release and caspase-9 activation and (iv) depletion of ATP ablates SST-induced cyt c release and caspase-9 activation, but not its ability to induce effector caspases and apoptosis. These data reveal that SHP-1-/caspase-8-mediated acidification occurs at a site other than the mitochondrion and that SST-induced apoptosis is not dependent on disruption of mitochondrial function and caspase-9 activation.

Value of DNA ploidy and S-phase fraction as prognostic factors in stage III cutaneous melanoma.

OBJECTIVE: To determine the prognostic value of flow cytometric analysis (S-phase fraction and DNA index) performed on lymph-node metastases of patients with stage III melanoma. DESIGN: A retrospective chart review with flow cytometric analysis of paraffin-embedded tissues. SETTING: A university teaching hospital. PATIENTS: Among 332 patients with cutaneous melanoma, 33 with stage III were identified. Distant metastases developed in 16 patients; 17 had no further recurrence. Charts were reviewed to obtain clinicopathologic parameters such as sex, age, location of the primary tumour, histologic features, presence or absence of ulceration, and Clark's and Breslow's levels. INTERVENTION: DNA ploidy and S-phase fraction were determined on the paraffin-embedded nodes. MAIN OUTCOME MEASURES: The groups with or without recurrence were compared in terms of disease-free survival (DFS) and overall survival (OS). These survival parameters were correlated with DNA ploidy and S-phase fraction. RESULTS: By univariate analysis, clinicopathologic factors did not predict OS. A higher Clark's level of invasion and more than 3 positive lymph nodes were associated with shorter DFS (p < 0.05). Tumour thickness and S-phase fraction did not correlate with either DFS or OS. Patients with diploid lymph-node metastases had an 87% 12-month survival compared with 41% for those with aneuploid tumours. CONCLUSIONS: DNA ploidy may be used as a prognostic index in patients with lymph-node metastases. This could be particularly useful in the context of sentinel lymph-node mapping by which more patients are being identified with single microscopic lymph-node involvement.

5-oxo-6,8,11,14-eicosatetraenoic acid is a potent stimulator of L-selectin shedding, surface expression of CD11b, actin polymerization, and calcium mobilization in human eosinophils.

5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is a metabolite of arachidonic acid formed by the oxidation of 5-hydroxy-6,8,11, 14-eicosatetraenoic acid by a highly specific dehydrogenase. 5-oxo-ETE is a chemoattractant for both neutrophils and eosinophils. Although it is not as effective as leukotriene B4 (LTB4) and platelet-activating factor (PAF) in stimulating neutrophil migration, we found that it is considerably more active than these and a variety of other lipid mediators as an eosinophil chemoattractant. Moreover, low concentrations of 5-oxo-ETE appear to enhance the responsiveness of these cells to PAF. The objectives of the current investigation were to identify rapid responses induced in eosinophils by 5-oxo-ETE that might be related to the infiltration of these cells into tissues. We found that 5-oxo-ETE is more effective than PAF and LTB4 in inducing both L-selectin shedding and actin polymerization in human eosinophils, whereas PAF is the most active of these mediators in stimulating calcium mobilization. The complementary effects of 5-oxo-ETE and PAF on actin polymerization and calcium mobilization may explain their synergistic effect on eosinophil migration. 5-oxo-ETE and PAF were equipotent in stimulating the surface expression of the beta2-integrin CD11b, but were slightly less potent than LTB4. 5-oxo-ETE- induced actin polymerization was subject to homologous but not heterologous desensitization. It was not prevented by incubation of eosinophils with inhibitors of protein kinase C (staurosporine), mitogen-activated protein kinase kinase (PD98059), or phosphatidylinositol-3-kinase (wortmannin). In conclusion, 5-oxo-ETE is a potent activator of human eosinophils and may be an important regulator of tissue infiltration of these cells.

Effects of 5-oxo-6,8,11,14-eicosatetraenoic acid on expression of CD11b, actin polymerization, and adherence in human neutrophils.

Human neutrophils contain a highly specific dehydrogenase that converts 5-hydroxy-6,8,11,14-eicosatetraenoic acid to 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE). 5-Oxo-ETE is a potent stimulator of calcium mobilization, chemotaxis, and aggregation in these cells and has similar effects on eosinophils. The primary objectives of the current study were to determine whether this compound could increase the surface expression of integrins and stimulate actin polymerization in neutrophils. 5-Oxo-ETE stimulated the expression of CD11b and, to a lesser extent, CD11c, on neutrophils, but had no significant effects on the expression of CD11a, CD16 (Fc gammaRIII), or CD32 (Fc gammaRII). Surface expression of CD11b in response to 5-oxo-ETE was maximal after 12 min and remained constant thereafter. The EC50 for this response (50 nM) was lowered to 20 nM by preincubation of neutrophils with PMA. 5-Oxo-ETE (EC50, 10 nM) also rapidly stimulated actin polymerization in neutrophils, with a maximal response at 20 s. This response was blocked by pretreatment of neutrophils with the Gi protein inhibitor, pertussis toxin, and by homologous desensitization due to preincubation with 5-oxo-ETE. However, preincubation with leukotriene B4 or platelet-activating factor had no effect on the response of neutrophils to subsequent addition of 5-oxo-ETE. The adherence of neutrophils to plasma-coated plastic was also stimulated by 5-oxo-ETE with a time course similar to that for the surface expression of CD11b. Low concentrations of PMA (0.3 nM) enhanced this response. These results raise the possibility that 5-oxo-ETE could contribute to the infiltration of neutrophils into inflammatory sites.

Human breast cancer: genetic alterations in the MET gene region.

OBJECTIVE: to test whether the MET gene at chromosome 7q31, which encodes a receptor protein (tyrosine kinase) related to normal histological differentiation, undergoes structural changes in breast cancer. A previous study reported somatic alterations detected as loss of heterozygosity (LOH) at this locus in breast cancer. DESIGN: Analysis of DNA from tumours and matched normal tissue by Southern blot hybridization with the metH probe; the tumours were also analysed for estrogen and progesterone receptors, ploidy and S phase, and protein expression of the MET and c-erbB-2 protooncogenes. PARTICIPANTS: Eighty-two patients with breast cancer. RESULTS: Fifty-three percent of the patients were informative for polymorphism with the metH marker. Somatic alterations of MET, consisting of LOH, were demonstrated in 22% of women who were informative and had breast cancer. No correlation was found between LOH of MET and conventional prognostic factors, or status for c-erbB-2 proto-oncogene expression. Estrogen-receptor status correlated with progesterone-receptor status, and S phase correlated with ploidy and size of the tumour. CONCLUSIONS: Somatic alterations of MET, detected as LOH with the metH probe, occur in 22% of informative patients. These alterations do not correlate with the prognostic factors established when the mastectomy is performed. It remains to be determined whether the patients' overall survival and disease-free survival rates are correlated with genetic alteration of MET.

Identification of natural suppressor cells in long-term renal allograft recipients.

We have previously reported an abnormal expansion of CD3+Leu7+ (CD57+) large granular lymphocytes in long-term renal allograft recipients. These cells lacked NK activity, T-helper activity and did not respond to T cell mitogens. The following studies were done in order to further define the functional characteristics of these cells. We sorted CD3+Leu7+ T cells from the peripheral blood of 45 recipients (all with good renal allograft function), and found that these cells suppress mixed lymphocyte culture responses and pokeweed mitogen-induced IgG secretion in a non-genetically restricted manner. PWM-induced IgG secretion assays are suppressed by 60-100%, and MLC responses are suppressed by 20-85% at a ratio of 1:10 CD3+Leu7+ cells to responder/effector cells. Supernatants from CD3+Leu7+ cell cultures are also suppressive. On the other hand, unsorted cells and non-CD3+Leu7+ sorted cells either enhance responses or produce less than 10% suppression under the same conditions. Patients who were tested more than once showed a relatively stable percentage and suppressive effect of their CD3+Leu7+ cells over an interval of 6-12 months. These nonspecifically suppressive CD3+Leu7+ large granular lymphocytes are similar in many ways to the natural suppressor cells that have been identified in hematopoietic tissues, in graft-vs.-host disease, and in the lymphoid organs of neonates.

Biochemical characterization and serological immunoassay of a pancreatic carcinoma-associated antigen defined by monoclonal antibody LD-B1.

Several glycosylated macromolecules associated with normal and malignant pancreatic ductal cells have been described. We have generated a monoclonal antibody, LD-B1, by immunizing Balb/c mice with the postmicrosomal extract of fresh human pancreatic ductal carcinoma tissue and used it in this study to characterize the nature of the target antigen. The antigen detected by LD-B1 antibody was purified to homogeneity by affinity chromatography. Enzymatic and biochemical analysis showed it to be a nonsialylated glycoprotein that on Western blotting and immunoprecipitation analyses had an apparent molecular weight of 300-400 kDa. The mobility on gels was not affected by reducing or denaturing conditions. Competitive inhibition assays with various MoAbs and lectins indicated that the epitope recognized by LD-B1 antibody involves the carbohydrate sequence Gal beta 1----3Gal beta 1----3(or 4)GlcNAc beta 1----3Gal. Using a double determinant sandwich ELISA, elevated antigen levels were detected in the sera of 5 of 6 patients with pancreatic carcinoma, 0 of 3 patients with chronic pancreatitis, and 12 of 137 normal controls. These results suggest that patients with pancreatic carcinoma exhibit altered expression of a heavily glycosylated molecule related to a blood group precursor immunodeterminant.

Isolation and immunohistochemical characterization of a pancreatic carcinoma-associated monoclonal antibody.

The aim of this study was to define a cellular antigen associated with human pancreatic ductal carcinoma, and to study its distribution in a large panel of malignant, benign, and normal tissues. For this purpose, monoclonal antibodies were generated against a postmicrosomal fraction of fresh human pancreatic cancer. One such antibody, LD-B1, reacted strongly with 95% of cases of primary and metastatic pancreatic ductal carcinomas. It also immunostained gallbladder carcinomas and cholangiocarcinomas. By contrast, it exhibited focal or weak reactivity to 10% of other types of common malignant tumors. On normal pancreas, staining was observed in ductal and centriacinar cells, but not in acinar or endocrine cells. In chronic pancreatitis, ductal staining intensity increased proportionally with the degree of cellular atypia. The antigen was also detected in gallbladder epithelium, bile ducts, ductal epithelium of sweat glands and salivary glands, and focally in a few other normal nonpancreatic tissues. These results suggest that LD-B1 MoAb can be used in immunohistochemical studies as a marker of pancreatic adenocarcinoma.