Tan, Po Hong

ABSTRACT Background and Objectives NCCN guidelines recommend right hemicolectomy (RHC) for appendiceal neuroendocrine tumors (aNETs) > 2 cm and observation for < 1 cm. However, optimal surgical management of 1–2 cm tumors remains controversial. This study compared long‐term survival and recurrence between patients undergoing RHC versus appendectomy (APY) for 1–2 cm aNETs. Methods Patients with pathologically confirmed 1–2 cm aNETs treated at three Mayo Clinic sites (1972–2024) were included. Primary outcomes were recurrence and all‐cause mortality after resection. Associations with lymph node (LN) metastasis were assessed in patients with lymphadenectomy. Results Sixty‐five patients were identified: 29 (45%) underwent APY, 35 (54%) RHC, and one ileocecectomy. Median age at diagnosis was 39 years; 71% were female and 94% white. LN positivity was 15.2% for tumors with nodes examined. Tumor size > 1.5 cm, stage T3/T4, and lymphovascular invasion were not associated with nodal metastasis. No survival differences were observed between APY and RHC. LN positivity did not impact survival. No recurrences occurred during a median follow‐up of 6.25 years (IQR 2.44–12.63). Conclusions Among patients with 1–2 cm aNETs, RHC conferred no survival benefit over APY. Absence of recurrence and the limited prognostic value of nodal disease suggest APY alone may suffice for this population.

BACKGROUND: Subtotal cholecystectomy is increasingly recommended as a bailout strategy for the difficult gallbladder, yet its long-term durability and the risk profile of subsequent completion cholecystectomy remain incompletely defined. STUDY DESIGN: We performed a population-based retrospective cohort study of adults undergoing laparoscopic or open subtotal cholecystectomy for acute cholecystitis from 2012 to 2021 using Healthcare Cost and Utilization Project state databases from New York and Florida. The primary endpoint was remnant cholecystitis, defined as a postoperative emergency, inpatient, or outpatient diagnosis of cholecystitis or need for subsequent cholecystectomy. Kaplan–Meier analysis estimated cumulative incidence. Secondary outcomes included completion cholecystectomy and bile duct injury requiring surgical repair. RESULTS: Among 2,682 patients (98.7% laparoscopic), the cumulative incidence of remnant cholecystitis was 13.3% during a median follow-up of 2 years (interquartile range [IQR] 0.7 to 4.1). The median time to developing remnant cholecystitis was 28 days (IQR 13 to 91), with 79.7% occurring within 6 months. Only 70 patients (2.6%) underwent completion cholecystectomy at a median of 103 days (IQR 43 to 202). Completion cholecystectomy was performed via open surgery in 47.1% of patients and was associated with a 7.1% bile duct injury rate and median length of stay of 3 days (IQR 1 to 7), compared with a 0.9% bile duct injury rate for subtotal cholecystectomy overall. CONCLUSIONS: Although remnant cholecystitis occurred in 13.3% of patients after subtotal cholecystectomy, few required completion cholecystectomy. When necessary, completion cholecystectomy was frequently open and associated with a substantially higher bile duct injury rate, supporting referral to experienced hepatobiliary centers for reoperation.

Abstract Background Robotic left pancreatectomy (RLP) is increasingly adopted worldwide. Current guidelines suggest a learning curve of 21 cases, yet its impact on major morbidity and oncological quality remains uncertain. Methods A retrospective multicentre international study was undertaken across 10 centres in the UK, Spain, Germany, the USA, and Australia (2014–2025). Consecutive patients undergoing RLP were categorised into competency (first 21 cases per centre) or proficiency phase (&gt;21). The primary outcome was major morbidity (Clavien–Dindo grade ≥ IIIa), and secondary outcome was the R1-margin rate. Mixed-effects logistic regression and risk-adjusted cumulative sum (RA-CUSUM) analyses were performed. Results 521 patients underwent RLP, including 200 (38.4%) in the competency phase and 321 (61.6%) in the proficiency phase. Median age was 63 years (IQR 54–73), and 56.4% were female. Rates of major morbidity were similar between phases (14.5% versus 14.0%, P = 0.981), as were R1 margin rates (21.6% versus 19.7%, P = 0.092). Independent predictors of major morbidity included male sex (OR 1.76, P = 0.037), preoperative pancreatitis (OR 2.23, P = 0.031), and multivisceral resection (OR 2.29, P = 0.034). Among patients with adenocarcinoma (n = 110), prolonged operative time (OR 1.39 per hour, P = 0.004) and nodal positivity (OR 2.62, P = 0.047) predicted R1 resection, while learning phase was not associated with margin status. RA-CUSUM demonstrated no excess morbidity over time in any centre. Conclusions In this first multicentre international analysis, the learning phase of RLP did not increase the risk of major morbidity or compromise oncological quality. These findings support the safe global adoption of RLP with appropriate training and case selection.

Background: ASCO recommends extended venous thromboembolism (VTE) prophylaxis with low-molecular-weight heparin (LMWH) or direct oral anticoagulants (DOACs) following cancer surgery. However, these recommendations were based on trials using routine venography, which detects asymptomatic VTEs, and real-life efficacy is not well studied. We aimed to assess the association of extended VTE prophylaxis with the incidence of clinically significant VTE after elective cancer surgery. Patients and Methods: In this retrospective, population-based cohort study, we identified patients who underwent surgical resection for lung, breast, esophageal, gastric, pancreas, and colon cancer from 2010 to 2017 using the SEER–Medicare linked dataset. Patients were divided into 1 of 2 main groups for comparative analyses: those who received extended VTE prophylaxis after cancer surgery and those who did not. Patients who received extended VTE prophylaxis after cancer surgery were identified as those prescribed prophylactic doses of LMWH or a DOAC within 7 days of discharge, as captured in Medicare Part D files. Results: A total of 113,739 Medicare beneficiaries were identified, of whom 1,570 (1.4%) received extended VTE prophylaxis. There was a year-over-year increase in the use of extended VTE prophylaxis during the study period, rising from 0.6% in 2010 to 3.3% in 2017. The overall incidence of VTE was 1.6% at 1 month, 4.3% at 6 months, 5.7% at 12 months, with significant differences observed across cancer types ( P <.001). However, patients who received extended VTE prophylaxis had a higher 1-year cumulative incidence of postoperative VTE compared with those who did not (11.4% vs 5.3%; P <.001), an association that was consistent across cancer sites. In adjusted analyses, extended VTE prophylaxis was independently associated with an increased risk of VTE (hazard ratio, 1.6; 95% CI, 1.3–2.0; P <.001). Extended prophylaxis was also associated with a higher 1-year incidence of bleeding events compared with patients who did not receive prophylaxis (12.0% vs 8.5%; P <.001). Conclusions: The utilization of extended VTE prophylaxis after cancer surgery remains low, although it has increased every year. Paradoxically, patients who received extended VTE prophylaxis had higher incidences of clinically significant VTE and bleeding compared with those who did not, likely reflecting patient selection and surveillance bias after surgery. In light of these findings, national guidelines recommending postoperative extended VTE prophylaxis, and its use as a surrogate for quality of care, should continue to be re-examined.

Background: Upfront resectable pancreatic ductal adenocarcinoma (PDAC) is defined by the NCCN as disease with ≤180° portomesenteric vein (PMV) abutment. However, the clinical significance of PMV abutment in this cohort remains unexplored, and we sought to investigate its impact. Methods: This multi-institutional study included patients who underwent pancreatoduodenectomy (PD) for upfront resectable PDAC from 2002 to 2023. Patients with PDAC with ≤180° PMV abutment were compared with those without. Overall survival (OS) was compared and stratified based on whether patients underwent upfront surgery or neoadjuvant therapy (NAT). Results: Among 1,446 patients included, 521 (36.0%) had PMV abutment. Median OS for patients with PMV abutment was 28.8 months compared with 31.2 months for those without ( P =.17). In a stratified analysis of patients who underwent upfront surgery, patients with PMV abutment had worse OS (19.2 vs 27.6 months; P <.05) and lower R0 resection rates (63.1% vs 87.2%; P <.05) compared with those without. However, in patients who underwent NAT, this difference in R0 resection rate was not observed (91.4% vs 94.0%, respectively; P =.27). Furthermore, there was no significant difference in median OS with NAT (42.5 vs 51.6 months, respectively; P =.48). Conclusions: In this largest cohort to date of patients with upfront resectable PDAC, PMV abutment was associated with worse OS compared with no PMV abutment when an upfront resection strategy was used. The use of NAT in patients with PMV abutment mitigated this survival difference with increased R0 resection rates. These findings suggest that patients with upfront resectable PDAC with PMV abutment benefit from a NAT approach for optimal survival outcomes, and that the current criteria guidelines need to be redefined.

Objective: We comparatively analyzed the longitudinal outcomes of conversion to open procedure, laparoscopic subtotal cholecystectomy (CCY), and laparoscopic cholecystostomy tube placement. Background: Severe cholecystitis often causes dense inflammation that distorts the hepatocystic anatomy and can make safe dissection during CCY challenging. However, controversy exists regarding the optimal bailout procedure in such situations. Methods: The New York and Florida State all-claims databases were queried for patients who underwent laparoscopic CCY for acute cholecystitis from 2012 to 2021. Hierarchical logistic regression models were used to obtain adjusted estimates, with fixed effects assigned to patient-level variables and random effects assigned to hospital identifiers to adjust for intraclass correlation. Results: Of 384,948 laparoscopic CCYs performed, 5448 (1.4%) were not completed laparoscopically; 1370 underwent conversion to open procedure, 2646 underwent laparoscopic subtotal CCY, and 1432 underwent laparoscopic cholecystostomy tube placement. The conversion to open rate decreased from 0.6% in 2012 to 0.3% in 2021, while the laparoscopic subtotal CCY rate increased from 0.2% in 2012 to 1.4% in 2021. The 1-year bile duct injury (BDI) rate was highest for the conversion to open group (4.4%), followed by the laparoscopic subtotal CCY (0.8%) and laparoscopic cholecystostomy tube groups (0.3%, P<0.001). On adjusted analyses with the conversion to open group as the control, laparoscopic subtotal CCY (OR: 0.17, P<0.001) and laparoscopic cholecystostomy tube were associated with lower BDI rates (OR: 0.08, P<0.001, Figure). The 1-year postoperative endoscopic biliary intervention rate was lowest for the conversion to open group (4.2%), followed by the laparoscopic subtotal CCY (8.4%) and the laparoscopic cholecystostomy tube groups (8.8%, P<0.001). The completion CCY rates for the laparoscopic subtotal CCY and laparoscopic cholecystostomy tube groups were 2.1% and 23.4%, respectively. Among completion CCYs, the open rates were 56.4% in the laparoscopic subtotal CCY group versus 24.5% in the laparoscopic cholecystostomy tube group (P<0.001). Conclusions: In patients with severe cholecystitis requiring a bailout procedure, the BDI rate was highest after conversion to open procedure. Laparoscopic subtotal CCY and laparoscopic cholecystostomy tube were associated with lower BDI rates at the cost of higher postoperative endoscopic biliary intervention rates. Completion CCYs were required in 2.1% and 23.4% of patients who underwent laparoscopic subtotal CCY and laparoscopic cholecystostomy tube placement, respectively, of which the former group’s CCY was more likely to require an open operation.

Summary of Background Data: Intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic cancer is typically managed like pancreatic intraepithelial neoplasia (PanIN)-derived pancreatic cancer. However, in IPMN-derived pancreatic cancer, the role of chemotherapy remains controversial, particularly in the neoadjuvant setting (NAT). Objective: To evaluate the role of neoadjuvant chemotherapy in IPMN-derived pancreatic cancer. Methods: Patients with IPMN-derived pancreatic cancer treated with either upfront surgery (US) or NAT were identified from eight international centers (2000-2023). Clinicopathologic data were compared. Date of first treatment was used for Kaplan-Meier and log-rank tests to compare overall (OS) and recurrence free survival (RFS). Multivariable Cox-regression was performed in patients that underwent NAT. Results: In 1,019 patients, 76 (7%) underwent NAT. Patients who received NAT had higher baseline CA19-9 levels (P<0.001). Of these 76 patients, 27 (36%), 20 (26%), and 29 (38%) had resectable, borderline resectable, or locally advanced pancreatic cancer at diagnosis, respectively. Advanced resectability stage was significantly more common in the NAT patients as compared to those who underwent US (P<0.001). OS for US patients was 38.0 months (95%CI: 33.7.1-44.3), which was not statistically different than those that received NAT [27.5 mo (95%CI: 23.1-46.7), P=0.121]. This was also valid for patients with resectable disease [US: 38.1 mo vs. NAT: 35.6 mo, P=0.920)]. Complete or marked pathological treatment response (P=0.046) and serological CA19-9 normalization after NAT (P=0.017) were associated with improved survival. On Cox-regression for OS, N2 disease [HR: 4.15 (95%CI: 1.71-10.10)], elevated CA19-9 [HR: 2.02 (95%CI:1.06-3.85)] and R1 margin [HR: 2.36 (95%CI:1.20-4.61)] was independently associated with OS after NAT, while resectability status was not. Conclusion: After NAT and resection, advanced resectability stage was not associated with worse OS indicating the value of this approach for borderline resectable and locally advanced IPMN-derived pancreatic cancer. The benefit of NAT in resectable disease is unclear and may require an individualized approach. Biological treatment effect can be assessed with CA19-9 and confirmed by pathologic response.