Objective: The study aimed to describe and compare minimally invasive surgery (MIS) and open surgery for rectal cancer in Peru. Material and methods: A retrospective single-center analysis was performed for all patients who underwent sphincter- sparing surgery for non-metastatic rectal cancer at Instituto Nacional de Enfermedades Neoplásicas in Peru between January 2016 and December 2020. Clinical, perioperative, pathological, and survival outcomes were compared between both groups. A propensity score matching method was used to minimize bias. Results: 162 patients were included in the final analysis. 124 had open surgery and 38 had MIS. Patients, clinical tumour, pathological characteristics, and perioperative were similar between groups after matching. Similar circumferential resection margin (CRM) with optimal quality of the mesorectum (p=1.000) but higher number of lymph nodes resected in open surgery group (p=0.741) was described. The leakage rate was slightly higher in the MIS group (p=0.358) with 10.5%, while the postoperative hospital stay was longer in the open surgery group after matching (p=0.001; OR 95% 5.2 CI: 1.8-15.6). The estimated recurrence-free survival (RFS) and overall survival (OS) at 3 years in open surgery and MIS was 71.8% (95% CI; 0.58-0.89) and 70% (95% CI; 0.56-0.88) (p=0.431) and 77.7% (95% CI; 0.64-0.94) and 88.9% (95% CI; 0.79-0.99) (p=0.5), respectively. Conclusions: Shorter postoperative hospital stay in the minimally invasive surgery group was reported. RFS, OS, and re lar between both groups. This approach is for non-metastatic rectal cancer in referral centers in Peru.

Purpose The role of tumor deposits (TDs) in the staging of gastric cancer is currently debatable. TDs are defined as tumoral nodules in perigastric adipose tissue with no evidence of lymphatic, vascular, or neural structures. Clinicopathological factors related to the presence of TDs are not well defined. This study aimed to identify the clinicopathological factors associated with the presence of TDs in resected gastric cancer patients. Materials and methods This prospective study included patients diagnosed with gastric cancer and treated with D2 radical gastrectomy from January 2019 to January 2020. Univariate and multivariate analyses were performed to determine the factors related to the presence of TDs. Results A total of 111 patients were eligible and TDs were present in 31 of them (28%). In the univariate analysis, male gender (p = 0.027), tumor size ≥ 5cm (p = ≤0.001), serosa and adjacent organs invasion (pT4a and pT4b) (p = ≤0.001), ≥16 metastatic lymph nodes (pN3b) (p = ≤0.001), and TNM stage III tumors (p = ≤0.001) were significantly associated with the presence of TDs. The multivariate analysis showed that a tumors size ≥5 cm (OR = 3.69, 95% CI: 1.17–11.6), serosa and adjacent organs invasion (pT4a and pT4b) (OR = 3.78, 95% CI: 1.31–10.86) and ≥16 metastatic lymph nodes (pN3b) (OR = 3.21, 95%CI:1.06–9.7) were independent risk factors for the presence of TDs. Conclusions Larger tumors (tumor size ≥ 5cm), serosa and adjacent organs invasion (pT4 and pT4b), and ≥16 metastatic lymph nodes (pN3b) were independent risk factors for the presence of TDs.

Highlights Transanal total mesorectum excision is feasible for mid and low rectal cancer. Good quality of the mesorectum specimen is obtain after TaTME surgery. TaTME with intersphincteric resection is a feasible option for selected cases of very low rectal cancer. Surgical complication rates after intersphincteric TaTME with hand-sewn coloanal anastomosis could be higher.

Introduction: Neoadjuvant chemotherapy for pancreatic cancer is increasingly utilized. However, no guidelines exist for optimal adjuvant therapy after pancreatectomy with a partial or poor response to neoadjuvant therapy. This qualitative study seeks to describe our institution's patterns of adjuvant chemotherapy regimen selection after neoadjuvant therapy. Methods: All patients at a single institution from January 2013 through June 2019 receiving neoadjuvant chemotherapy followed by pancreatectomy for pancreatic cancer were reviewed. Patients enrolled in trials limiting chemotherapy or with missing medical oncology notes were excluded. Chemotherapy regimen, the College of American Pathologists pathologic tumor response, and medical oncology plans were recorded. Results: Fifty-three patients were reviewed and 41 patients met inclusion criteria. Neoadjuvant chemotherapy regimen are shown. Twenty-nine (70.7%) underwent pancreatoduodenectomy, 10 (24.3%) distal pancreatectomy, and 2 (4.8%) total pancreatectomy. Pathologic review of treatment effect demonstrated that 3 (7.3%) patients had complete pathologic response (cPR), 3 (7.3%) had near cPR, 16 (39%) had partial response, and 14 (34.1%) had poor/no response to neoadjuvant chemotherapy. Treatment effect was missing in 5 (12.2%) patients. Thirty-three (80.5%) patients received adjuvant chemotherapy, with 15 (45.5%) switching regimen adjuvantly. Pathology results guided therapy in 53.6% of patients and tumor response specifically guided therapy in 11 (30.5%) patients.Conclusions: Despite 73.1% of patients having partial or poor response to neoadjuvant chemotherapy, only 45.5% switched chemotherapy adjuvantly. Medical oncologists rarely considered treatment effect when choosing adjuvant therapy. Future trials should be designed to determine the optimal adjuvant regimen guided by pathologic treatment effect of neoadjuvant therapy.