Alterations in ERBB2 and BRCA and microsatellite instability as new personalized treatment options in small bowel carcinoma

Kelch-like proteins in the gastrointestinal tumors

Gastrointestinal tumors have become a worldwide health problem with high morbidity and poor clinical outcomes. Chemotherapy and surgery, the main treatment methods, are still far from meeting the treatment needs of patients, and targeted therapy is in urgent need of development. Recently, emerging evidence suggests that kelch-like (KLHL) proteins play essential roles in maintaining proteostasis and are involved in the progression of various cancers, functioning as adaptors in the E3 ligase complex and promoting the specific degradation of substrates. Therefore, KLHL proteins should be taken into consideration for targeted therapy strategy discovery. This review summarizes the current knowledge of KLHL proteins in gastrointestinal tumors and discusses the potential of KLHL proteins as potential drug targets and prognostic biomarkers.

Clinical practice guidelines for duodenal cancer 2021

Duodenal cancer is considered to be a small intestinal carcinoma in terms of clinicopathology. In Japan, there are no established treatment guidelines based on sufficient scientific evidence; therefore, in daily clinical practice, treatment is based on the experience of individual physicians. However, with advances in diagnostic modalities, it is anticipated that opportunities for its detection will increase in future. We developed guidelines for duodenal cancer because this disease is considered to have a high medical need from both healthcare providers and patients for appropriate management. These guidelines were developed for use in actual clinical practice for patients suspected of having non-ampullary duodenal epithelial malignancy and for patients diagnosed with non-ampullary duodenal epithelial malignancy. In this study, a practice algorithm was developed in accordance with the Minds Practice Guideline Development Manual 2017, and Clinical Questions were set for each area of epidemiology and diagnosis, endoscopic treatment, surgical treatment, and chemotherapy. A draft recommendation was developed through a literature search and systematic review, followed by a vote on the recommendations. We made decisions based on actual clinical practice such that the level of evidence would not be the sole determinant of the recommendation. This guideline is the most standard guideline as of the time of preparation. It is important to decide how to handle each case in consultation with patients and their family, the treating physician, and other medical personnel, considering the actual situation at the facility (and the characteristics of the patient).

Case Report: Molecular Features and Treatment Options for Small Bowel Adenocarcinoma

Small bowel adenocarcinoma (SBA) is a rare malignancy characterized by poor prognosis. Recent efforts have sought to elucidate the genetic landscape and the molecular drivers behind this disease. Herein, we report the main molecular alterations in two metastatic (stage IV) SBA patients. Interestingly, one of them had gene alterations that affected signaling pathways previously described for SBA. However, a second patient displayed previously unreported alterations in this particular tumor type. Based on these findings we discuss potential treatment options for patients affected by this rare, aggressive disease.

BRCA in Gastrointestinal Cancers: Current Treatments and Future Perspectives

A strong association between pancreatic cancer and BRCA1 and BRCA2 mutations is documented. Based on promising results of breast and ovarian cancers, several clinical trials with poly (ADP-ribose) polymerase inhibitors (PARPi) are ongoing for gastrointestinal (GI) malignancies, especially for pancreatic cancer. Indeed, the POLO trial results provide promising and awaited changes for the pancreatic cancer therapeutic landscape. Contrariwise, for other gastrointestinal tumors, the rationale is currently only alleged. The role of BRCA mutation in gastrointestinal cancers is the subject of this review. In particular, we aim to provide the latest updates about novel therapeutic strategies that, exploiting DNA repair defects, promise to shape the future therapeutic scenario of GI cancers.

BRCA1 and BRCA2 Gene Mutations and Lung Cancer Sisk: A Meta-Analysis

Background and objective: BRCA1 and BRCA2 are associated with many cancer types in addition to hereditary breast and ovarian cancers. However, their relation to lung cancer remains to be explored. Materials and Methods: Observation studies were systematically reviewed to explore the association of BRCA1 or BRCA2 with lung cancer. PubMed, MEDLINE [EBSCOhost], and relevant articles published up to 7 January 2020 were searched. Odd ratio (OR), standardized morbidity rate (SMR), and cancer-specific standardized incidence ratios (SIRs) were pooled together as relative risk (RR) estimates (95% confidence interval [CI], 0.66-1.40). Results: Thirteen studies were included for analysis. Results showed that the RR of BRCA2 is 0.76 (95% CI, 0.48-1.19), the overall RR is 0.96 (95% CI, 0.66-1.40), and that of BRCA1 is 0.66 (95% CI, 0.41-1.05), indicating that it was not associated with lung cancer. Conclusion: With the limitation of the retrospective study design and severe heterogeneity, these results inform clinicians and relevant families that BRCA1 and BRCA2 mutation carriers have no increased risk of lung cancer.

Prognostic relevance of programmed death-ligand 1 expression and microsatellite status in small bowel adenocarcinoma

Background: Small bowel adenocarcinoma (SBA) is a dreadful disease. Patient prognosis is limited due to late presentation and ineffective chemotherapy. PD-1/PD-L1 checkpoint immunotherapy is regarded as a promising approach in several cancer entities. The association of PD-1/PD-L1 expression and its impact on patient prognosis with SBA is unclear. Material and methods: Seventy-five consecutive patients who underwent surgery for SBA were retrospectively analyzed and stained for PD-L1 expression in the tumour or the stroma. Analysis of mismatch repair genes was performed to determine microsatellite status. Kaplan-Meier estimate was used to analyze patient survival. Univariate and multivariable Cox regression-analyses were used to assess the impact of PD-L1 expression and microsatellite status on patient survival.Results: PD-L1 was weakly upregulated within the tumour or the stroma and associated with prolonged survival (p = .0071 and p = .0472, respectively). Fifty-one tumours (68%) revealed microsatellite stability (MSS) and 24 tumours (32%) were microsatellite instable (MSI) without correlating with patient survival (p = .611). Neither PD-L1 expression in the tumour nor in the stroma was identified as an independent risk factor influencing survival (p = .572 and p = .3055).Conclusion: Although PD-L1 expression is associated with prolonged survival, it was not identified as an independent prognostic marker. Microsatellite status did not influence long-term survival.