PURPOSE: No biomarker capable of improving selection and monitoring of patients with rectal cancer managed by watch-and-wait (W&W) strategy is currently available. Prognostic performance of the Immunoscore biopsy (IS_B) was recently suggested in a preliminary study. METHODS: This international validation study included 249 patients with clinical complete response (cCR) managed by W&W strategy. Intratumoral CD3+ and CD8+ T cells were quantified on pretreatment rectal biopsies by digital pathology and converted to IS_B. The primary end point was time to recurrence (TTR; the time from the end of neoadjuvant treatment to the date of local regrowth or distant metastasis). Associations between IS_B and outcomes were analyzed by stratified Cox regression adjusted for confounders. Immune status of tumor-draining lymph nodes (n = 161) of 17 additional patients treated by neoadjuvant chemoradiotherapy and surgery was investigated by 3'RNA-Seq and immunofluorescence. RESULTS: Recurrence-free rates at 5 years were 91.3% (82.4%-100.0%), 62.5% (53.2%-73.3%), and 53.1% (42.4%-66.5%) with IS_B High, IS_B Intermediate, and IS_B Low, respectively (hazard ratio [HR; Low v High], 6.51; 95% CI, 1.99 to 21.28; log-rank P = .0004). IS_B was also significantly associated with disease-free survival (log-rank P = .0002), and predicted both local regrowth and distant metastasis. In multivariate analysis, IS_B was independent of patient age, sex, tumor location, cT stage (T, primary tumor; c, clinical), cN stage (N, regional lymph node; c, clinical), and was the strongest predictor for TTR (HR [IS_B High v Low], 6.93; 95% CI, 2.08 to 23.15; P = .0017). The addition of IS_B to a clinical-based model significantly improved the prediction of recurrence. Finally, B-cell proliferation and memory in draining lymph nodes was evidenced in the draining lymph nodes of patients with cCR. CONCLUSION: The IS_B is validated as a biomarker to predict both local regrowth and distant metastasis, with a gradual scaling of the risk of pejorative outcome.

Neuroendocrine tumors (NET) include a spectrum of malignancies arising from neuroendocrine cells throughout the body. The objective of this clinical investigation of retrospectively and prospectively collected data was to describe the prevalence, demographic data, clinical symptoms and methods of diagnosis of NET and the treatment and long‑term follow‑up of patients with NET. Data were provided by the participating centers and assessed for consistency by internal reviewers. All the cases were centrally evaluated (when necessary) by the pathologists in our group. The tissue samples were reviewed by hematoxylin and eosin and immunohistochemical staining techniques to confirm the diagnosis of NET. In total, 532 cases were documented: 461 gastroenteropancreatic‑NET (GEP‑NET) and 71 bronchial NET (BNET). All the tumors were immunohistochemically defined according to the World Health Organization (WHO) and European Neuroendocrine Tumor Society criteria. The most common initial symptoms in GEP‑NET were abdominal pain, diarrhea, bowel obstruction, flushing, gastrointestinal bleeding and weight loss. The most common tumor types were carcinoid (58.0%), non‑functional pancreatic tumor (23.0%), metastatic NET of unknown primary (16.0%) and functional pancreatic tumor (3.0%). Of the BNET, 89.0% were typical and 11.0% atypical carcinoids. of the patients with GEP‑NET, 59.2% had distant metastasis at diagnosis. The locations of the primary tumors in GEP‑NET were the small bowel (26.9%), pancreas (25.2%), colon‑rectum (12.4%), appendix (7.6%), stomach (6.9%), esophagus (2.8%), duodenum (2.0%) and unknown primary (16.3%). The histological subtypes based on the WHO classification were well‑differentiated NET (20.1%), well‑differentiated neuroendocrine carcinomas (66.5%) and poorly differentiated neuroendocrine carcinomas (10.3%). Overall, 67.3% of the patients underwent surgery, 41.2% with curative intent and 26.1% for palliative purposes. The 5‑year survival rates were 65.1% (95% confidence interval, 58.0‑71.4%) in GEP‑NET and 100.0% in typical carcinoid of the lung. This observational, non‑interventional, longitudinal study aimed to accumulate relevant information regarding the epidemiology, clinical presentation and current practices in the treatment of NET patients in Argentina, providing insight into regional differences and patterns of care in this heterogeneous disease.

The background to this study was that factors associated with carcinoid heart disease (CHD) and its impacts on overall survival (OS) are scantly investigated in patients (pts) with neuroendocrine tumors (NETs). In terms of materials and methods, a retrospective multicenter cohort study was conducted of factors associated with CHD in advanced NET pts with carcinoid syndrome (CS) and/or elevated urinary 5-hidroxyindole acetic acid (u5HIAA). CHD was defined as at least moderate right valve alterations. The results were the following: Among the 139 subjects included, the majority had a midgut NET (54.2%), 81.3% had CS, and 93% received somatostatin analogues. In a median follow-up of 39 months, 48 (34.5%) pts developed CHD, with a higher frequency in pts treated in public (77.2%) versus private settings (22.9%). In a multivariate logistic regression, unknown primary or colorectal NETs (Odds Ratio (OR) 4.35; p = 0.002), at least 50% liver involvement (OR 3.45; p = 0.005), and being treated in public settings (OR 4.76; p = 0.001) were associated with CHD. In a Cox multivariate regression, bone metastases (Hazard Ratio {HR} 2.8; p = 0.031), CHD (HR 2.63; p = 0.038), and a resection of the primary tumor (HR 0.33; p = 0.026) influenced the risk of death. The conclusions were the following: The incidence of CHD was higher in pts with a high hepatic tumor burden and in those treated in a public system. Delayed diagnosis and limited access to effective therapies negatively affected the lives of NET patients.