Background: Neoadjuvant chemoradiotherapy (nCRT) is the standard treatment for locally advanced rectal cancer, but only 15–30% of patients achieve a pathological complete response. Single nucleotide polymorphisms represent stable genetic markers with potential predictive value for treatment response. This systematic review synthesizes current evidence on the association between SNPs and the response to nCRT in rectal cancer. Methods: PubMed and Web of Science databases were searched for relevant English studies. Two reviewers independently screened the titles and abstracts using the DistillerSR tool. Full-text articles were assessed for their eligibility. Data extraction followed the PRISMA guidelines, and the risk of bias was assessed. Results: Thirty-two studies (4116 patients) assessed 304 SNPs across 126 genes in 407 analyses. DNA repair genes (XRCC1, XRCC3, ERCC1, ERCC2) and folate metabolism genes (MTHFR, TYMS) were most frequently investigated. Only two SNPs demonstrated predictive value in multiple studies: rs25487 (XRCC1) and rs1801133 (MTHFR); however, the associations were inconsistent. The remaining SNPs showed isolated associations in single studies. No SNP demonstrated predictive value across independent cohorts. Conclusions: Current evidence does not support the clinical use of individual SNPs to predict nCRT response in rectal cancer patients. Although XRCC1 and MTHFR polymorphisms have been extensively studied, their predictive utility remains inconclusive. Future research should prioritize large, multicenter prospective studies with standardized treatment and outcome definitions, and consider polygenic risk models or integrated multi-omic approaches.

The standard of care for resectable oesophageal cancer includes neoadjuvant chemotherapy followed by oesophagectomy.1–3 Advances in systemic therapy have resulted in histopathologic tumour regression to ≤ypT1 N0 in up to 45% of patients.4–6 However, endoscopic assessment with biopsy is unreliable, missing residual tumour in up to 60–70% of cases.7 8 In such situations, the need for radical surgery solely to confirm complete disease eradication remains uncertain. Recent advances in endoscopic techniques allow local excision and accurate histological assessment of treatment response via natural orifice approaches. We present a patient with locally advanced gastro-oesophageal junction adenocarcinoma who declined surgery after neoadjuvant therapy and instead underwent ESD to evaluate response and guide further management.

Although endoscopic papillectomy is an established minimally invasive alternative to surgical resection for ampullary tumors, its technical aspects remain poorly defined. This study aimed to identify factors associated with piecemeal resection and recurrence-free survival after endoscopic papillectomy. A multicenter, retrospective analysis of consecutive patients who underwent endoscopic papillectomy in six tertiary Polish centers between 2011 and 2023 was performed. Multivariable logistic and Cox regression models were applied. A total of 192 patients were included. Adverse events occurred in 26.6% of patients. The most frequent were bleeding (17.3%) and acute pancreatitis (15.6%). En bloc resection was achieved in 66.1% of tumors. Larger tumor size (odds ratio [OR] 1.07 per mm increase; 95% confidence interval [CI] 1.02–1.12]; P = 0.004) and submucosal injection (OR 5.50; 95% CI 1.82–16.68; P = 0.003) were associated with piecemeal resection. Among 142 patients with a median follow-up of 12 months, recurrence occurred in 40.8%. Tumor size (hazard ratio [HR] 1.04 per mm increase; 95% CI 1.03–1.06; P < 0.001) and piecemeal resection (HR 2.37; 95% CI 1.23–4.57; P = 0.010) were independently associated with shorter recurrence-free survival. Larger tumors and piecemeal resection were independently associated with shorter recurrence-free survival. Optimization of technical aspects to achieve higher en bloc resection rates may be critical to reduce recurrence.