Little is known about the features and outcomes of Brazilian patients with pancreatic cancer. We sought to describe the socio-economic characteristics, patterns of health care access, and survival of patients diagnosed with malignant pancreatic tumors from 2000 to 2014 in São Paulo, Brazil. We included patients with malignant exocrine and non-classified pancreatic tumors according to the International Classifications of Disease (ICD)-O-2 and -O-3, diagnosed from 2000 to 2014, who were registered in the FOSP database. Prognostic factors for overall survival (OS) in the subgroup of patients with ductal or non-specified (adeno)carcinoma were evaluated using Cox proportional hazard model. The study population consists of 6855 patients. Median time from the first visit to diagnosis and treatment were 13 (Interquartile range [IQR] 4–30) and 24 (IQR 8–55) days, respectively. Both intervals were longer for patients treated in the public setting. Median OS was 4.9 months (95% confidence interval [95% CI] 4.7–5.2). Increasing age, male gender, lower educational level, treatment in the public setting, absence of treatment, advanced stage, and treatment from 2000 to 2004 were associated with inferior OS. From 2000–2004 to 2010–2014, no improvement in OS was seen for patients treated in the public setting. Survival of patients with malignant pancreatic tumors remains dismal. Socioeconomical variables, especially health care funding, are major determinants of survival. Further work is necessary to decrease inequalities in access to medical care for patients with pancreatic cancer in Brazil.

ObjectiveTo better understand the immune microenvironment of pancreatic ductal adenocarcinomas (PDACs), here we explored the relevance of T and B cell compartmentalisation into tertiary lymphoid structures (TLSs) for the generation of local antitumour immunity.DesignWe characterised the functional states and spatial organisation of PDAC-infiltrating T and B cells using single-cell RNA sequencing (scRNA-seq), flow cytometry, multicolour immunofluorescence, gene expression profiling of microdissected TLSs, as well as in vitro assays. In addition, we performed a pan-cancer analysis of tumour-infiltrating T cells using scRNA-seq and sc T cell receptor sequencing datasets from eight cancer types. To evaluate the clinical relevance of our findings, we used PDAC bulk RNA-seq data from The Cancer Genome Atlas and the PRINCE chemoimmunotherapy trial.ResultsWe found that a subset of PDACs harbours fully developed TLSs where B cells proliferate and differentiate into plasma cells. These mature TLSs also support T cell activity and are enriched with tumour-reactive T cells. Importantly, we showed that chronically activated, tumour-reactive T cells exposed to fibroblast-derived TGF-β may act as TLS organisers by producing the B cell chemoattractant CXCL13. Identification of highly similar subsets of clonally expandedCXCL13+tumour-infiltrating T cells across multiple cancer types further indicated a conserved link between tumour-antigen recognition and the allocation of B cells within sheltered hubs in the tumour microenvironment. Finally, we showed that the expression of a gene signature reflecting mature TLSs was enriched in pretreatment biopsies from PDAC patients with longer survival after receiving different chemoimmunotherapy regimens.ConclusionWe provided a framework for understanding the biological role of PDAC-associated TLSs and revealed their potential to guide the selection of patients for future immunotherapy trials.

Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixture found in Brazil, stimulated the implementation of the GE4GAC project. GE4GAC aims to embrace epidemiological, clinical, molecular and microbiological data from Brazilian controls and patients with malignant and pre-malignant gastric disease. In this letter, we summarize the main goals of the project, including subject and sample accrual and current findings.

The heterogeneity of response to neoadjuvant chemoradiotherapy (NCRT) is still a challenge in locally advanced rectal cancer (LARC). The evaluation of thymidylate synthase (TYMS) and RAD23 homolog B (RAD23B) expression in circulating tumor cells (CTCs) provides complementary clinical information. CTCs were prospectively evaluated in 166 blood samples (63 patients) with LARC undergoing NCRT. The primary objective was to verify if the absence of RAD23B/TYMS in CTCs would correlate with pathological complete response (pCR). Secondary objectives were to correlate CTC kinetics before (C1)/after NCRT (C2), in addition to the expression of transforming growth factor-β receptor I (TGF-βRI) with survival rates. CTCs were isolated by ISET and evaluated by immunocytochemistry (protein expression). At C1, RAD23B was detected in 54.1% of patients with no pCR and its absence in 91.7% of patients with pCR (p = 0.014); TYMS− was observed in 90% of patients with pCR and TYMS+ in 51.7% without pCR (p = 0.057). Patients with CTC2 > CTC1 had worse disease-free survival (DFS) (p = 0.00025) and overall survival (OS) (p = 0.0036) compared with those with CTC2 ≤ CTC1. TGF-βRI expression in any time correlated with worse DFS (p = 0.059). To conclude, RAD23B/TYMS and CTC kinetics may facilitate the personalized treatment of LARC.

OBJECTIVES:The number of pancreatic transplants has decreased in recent years. Pancreatic grafts have been underutilized compared to other solid grafts. One cause of discard is the macroscopic appearance of the pancreas, especially the presence of fatty infiltration. The current research is aimed at understanding any graft-related association between fatty tissue infiltration of the pancreas and liver steatosis.METHODS:From August 2013 to August 2014, a prospective cross-sectional clinical study using data from 54 multiple deceased donor organs was performed.RESULTS:Micro- and macroscopic liver steatosis were significantly correlated with the donor body mass index ([BMI]; p=0.029 and p=0.006, respectively). Positive gamma associations between pancreatic and liver macroscopic and microscopic findings (0.98; confidence interval [CI]: 0.95–1 and 0.52; CI 0.04–1, respectively) were observed. Furthermore, comparisons of liver microscopy findings showed significant differences between severe versus absent (p<0.001), severe versus mild (p<0.001), and severe versus moderate classifications (p<0.001). The area under the receiver operating curve was 0.94 for the diagnosis of steatosis by BMI evaluation using a cut-off BMI of 27.5 kg/m2, which yielded 100% sensitivity, 87% specificity, and 100% negative predictive value.CONCLUSIONS:We observed a positive association of macroscopic and microscopic histopathological findings in steatotic livers with adipose infiltration of pancreatic grafts.

Background: In 2019, WHO subclassified grade 3 (G3) gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) into neuroendocrine carcinoma (NEC) or tumors (G3 NET). Yet, few data exist on clinical and molecular profiles for G3 NEN. We aimed to compare the clinicopathological and molecular characteristics of G3 GEP NET and GEP NEC.Methods: We retrospectively collected data of all G3 GEP NEN patients (pts) diagnosed and treated at our cancer center from 2000 to 2019. Cases with available tumor tissues were reviewed and reclassified according to the WHO 2019 classification. Formalin-fixed, paraffin-embedded NEN tissues had DNA extracted for genomic profiling through next-generation sequencing (NGS), which evaluated mutations profiles, tumor mutation burden (TMB) and the presence of microsatellite instability. Survival from treatment start was the primary endpoint.Results: Seventy-seven pts were included: median age at the diagnosis was 56 (26-91) years and 62% (48/77) were males. The most common primary sites were gastric (27%, 21/77), pancreas (23%, 18/77) and unknown primary NEN (23%, 18/77). Metastatic disease was present in 69% at diagnosis and 91% developed metastasis.Out of 77, 43 (56%) had pathology revision: 29 cases were NEC (67%) and 14 were reclassified as G3 NET (33%), with a change in diagnosis of 23%. In a median follow-up of 44 months, median OS in non-pancreatic digestive G3 NET, pancreatic G3 NET, and GEP NEC were 23.7, 55.6 and 10.8 months, respectively (non-pancreatic G3 NET vs NEC, p¼0.01). Median OS in G3 NET with ki67 > 55%, NEC 55% was 19, 25 and 8 months, respectively. In Cox regression multivariate analysis, only cell differentiation sustained as a risk of death (HR 3.14 NEC vs G3 NET; P ¼ 0.025). NGS was performed in 42% (32/77) cases: 21 NEC and 11 G3 NET. Median tumour mutational burden was 5.67 (0 e 66.82) mutations per megabase among NEC and 4.52 (0 e 8.83) among G3 NET. Tumors were microsatellite unstable in 3 (14.3%) NEC cases but zero among G3 NET pts. The most commonly mutated genes in G3 NET were TP53 (N¼3; 27.3%), CDKN2A (N¼3; 27.3%) and KRAS (2/11, 18.2%) and TP53 (N¼15; 71.4%), Rb1 (N¼7; 33.3%), PTEN (N¼6; 28.6%) and APC (N¼4; 19%) among NEC. Conclusion:Non-pancreatic digestive G3 NET is associated with increased survival compared to NEC. Pathology revision is essential to estimate prognosis and consequently therapeutic plan, as some of G3 NET can be treated as G2 NET. While G3 GEP NEN generally harbours low TMB and fewer actionable mutations, 14% of NEC cases were microsatellite unstable and could benefit from immune checkpoint inhibitors.Legal entity responsible for the study: The authors.

Extra-pulmonary neuroendocrine carcinomas (EP-NECs) are lethal cancers with limited treatment options. Identification of contributing factors to the observed heterogeneity of clinical outcomes within the EP-NEC family is warranted, to enable identification of effective treatments. A multicentre retrospective study investigated potential differences in “real-world” treatment/survival outcomes between small-cell (SC) versus (vs.) non-SC EP-NECs. One-hundred and seventy patients were included: 77 (45.3%) had SC EP-NECs and 93 (54.7%) had non-SC EP-NECs. Compared to the SC subgroup, the non-SC subgroup had the following features: (1) a lower mean Ki-67 index (69.3% vs. 78.7%; p = 0.002); (2) a lower proportion of cases with a Ki-67 index of ≥55% (73.9% vs. 88.7%; p = 0.025); (3) reduced sensitivity to first-line platinum/etoposide (objective response rate: 31.6% vs. 55.1%, p = 0.015; and disease control rate; 59.7% vs. 79.6%, p = 0.027); (4) worse progression-free survival (PFS) (adjusted-HR = 1.615, p = 0.016) and overall survival (OS) (adjusted-HR = 1.640, p = 0.015) in the advanced setting. Within the advanced EP-NEC cohort, subgroups according to morphological subtype and Ki-67 index (<55% vs. ≥55%) had significantly different PFS (adjusted-p = 0.021) and OS (adjusted-p = 0.051), with the non-SC subgroup with a Ki-67 index of <55% and non-SC subgroup with a Ki-67 index of ≥55% showing the best and worst outcomes, respectively. To conclude, the morphological subtype of EP-NEC provides complementary information to the Ki-67 index and may aid identification of patients who could benefit from alternative first-line treatment strategies to platinum/etoposide.

Whereas targeted and shotgun sequencing approaches are both powerful in allowing the study of tissue-associated microbiota, the human: microorganism abundance ratios in tissues of interest will ultimately determine the most suitable sequencing approach. In addition, it is possible that the knowledge of the relative abundance of bacteria and fungi during a treatment course or in pathological conditions can be relevant in many medical conditions. Here, we present a qPCR-targeted approach to determine the absolute and relative amounts of bacteria and fungi and demonstrate their relative DNA abundance in nine different human tissue types for a total of 87 samples. In these tissues, fungi genomes are more abundant in stool and skin samples but have much lower levels in other tissues. Bacteria genomes prevail in stool, skin, oral swabs, saliva, and gastric fluids. These findings were confirmed by shotgun sequencing for stool and gastric fluids. This approach may contribute to a more comprehensive view of the human microbiota in targeted studies for assessing the abundance levels of microorganisms during disease treatment/progression and to indicate the most informative methods for studying microbial composition (shotgun versus targeted sequencing) for various samples types.