Search

Background: Surgery represents the only curative treatment for stage I-III midgut neuroendocrine tumors (NETs). At present, there are very limited data on the risk of postoperative recurrence. The optimal modality, duration and frequency of surveillance have not been well established. In this work, we investigated the long-term risk of recurrence, peak timing of recurrence, and potential predictors of relapse in patients with stage I-III midgut NETs., Methods: We retrospectively evaluated 129 patients with stage I-III midgut NETs who were seen at the Moffitt Cancer Center between 2000 and 2010 following an R0/R1 resection. Disease-free survival (DFS) was estimated using the Kaplan-Meier method. Demographic, clinical, and pathological features were assessed as potential predictors of recurrence. All statistical tests were two-sided., Results: After a median postoperative follow-up of 81 months (range = 1-295 months), recurrence was diagnosed in 40 out of 129 patients (31.0%, 95% confidence interval [CI] = 23.0% to 39.0%). Liver, mesentery, and pelvic lymph nodes were the main sites of relapse. The median DFS was 138 months (95% CI = 117 to 223 months). Resection of 17 or fewer lymph nodes predicted relapse (P = .01) and shorter DFS (P = .04). Among patients who relapsed, the cumulative risks of recurrence at one, five, and 10 years were 15.0% (95% CI = 3.9% to 26.1%), 50.0% (95% CI = 34.5% to 65.5%), and 85.0% (95% CI = 73.9% to 96.0%). No recurrence was observed among patients (n = 6) with stage I tumors, whereas similar rates of relapse were noted in patients with stage II or III NETs (n = 118)., Conclusions: An annual surveillance interval may allow early detection of recurrence. Given the apparent decline in recurrence after eight years from surgery, a decade-long duration of active surveillance may be proposed.

Introduction: Tissue microarrays (TMA) enable rapid analysis of biomarkers in large-scale studies involving archival tumor specimens, however, their utility in heterogeneous tumors such as ovarian cancer is limited., Methods: In this study, immunohistochemical analysis was done on TMAs comprised of epithelial ovarian cancer (EOC) to estimate the prevalence of loss of expression of three mismatch repair proteins. TMAs were initially created using cores sampled from the center of donor tissue blocks from 59 EOC cases. Full sections were subsequently created and levels of expression were compared between tissues sampled from the central portion versus the periphery. Follow-up analyses were done by obtaining cores from the periphery of up to five additional donor blocks per case. A linear mixed model for each protein was used to investigate differences between results from the initial and follow-up blocks., Results: In the original TMAs created using centrally sampled cores, loss of mismatch repair expression was noted in 17 (29%) of the 59 cases. By comparison, analyses from peripherally sampled cores revealed loss of expression in only 6 of these 17 cases. For each protein, significant differences (P < 0.05) were detected between results from the initial donor block and the majority of the follow-up blocks., Conclusions: Our investigations, based on EOC, suggest that sampling variability in protein expression may result when TMAs are used. Thus, at least for EOC, it is important to preferentially sample from the periphery of tumor blocks where exposure to tissue fixatives is optimal.