Expression of PD-L1 in Patients With Malignant Peritoneal Mesothelioma: A Pilot Study.

INTRODUCTION: Frequency of PD-L1 expression and the role of immunotherapy in malignant peritoneal mesothelioma (MPM) have not been well characterized. The purpose of this study was to determine PD-L1 expression in patients with MPM and perform an exploratory analysis for associations between PD-L1 and its biological behavior in MPM. METHODS: Tumor samples were collected from patients undergoing surgical interventions between January 2018 and June 2020. Specimens were stained with anti-PD-L1 antibodies (Dako 22c3) and positivity was determined by tumor proportion score (TPS) or combined positive score (CPS) being ≥1%. RESULTS: Twenty one samples were obtained from 21 patients. Sixteen of 21 (76%) samples were CPS positive and 9 of 21 (43%) were TPS positive. Three samples had more aggressive biphasic/sarcomatoid histology and a high CPS and TPS (CPS: 3, 75, 95%; TPS: 2, 60, 90%). On an exploratory analysis, as the CPS or TPS threshold increased, there was a trend towards worse survival. CONCLUSIONS: MPM has a high frequency of PD-L1 expression, which may be associated with more aggressive tumor biology. These data provide the foundation for continued evaluation of checkpoint inhibition in patients with MPM.

Effect of the COVID-19 pandemic on surgical oncology practice-Results of an SSO survey.

BACKGROUND AND OBJECTIVES: The COVID-19 pandemic significantly affected healthcare delivery, shifting focus away from nonurgent care. The aim of this study was to examine the impact of the pandemic on the practice of surgical oncology. METHODS: A web-based survey of questions about changes in practice during the COVID-19 pandemic was approved by the Society of Surgical Oncology (SSO) Research and Executive Committees and sent by SSO to its members. RESULTS: A total of 121 SSO members completed the survey, 77.7% (94/121) of whom were based in the United States. Breast surgeons were more likely than their peers to refer patients to neoadjuvant therapy (p = 0.000171). Head and neck surgeons were more likely to refer patients to definitive nonoperative treatment (p = 0.044), while melanoma surgeons were less likely to do so (p = 0.029). In all, 79.2% (95/120) of respondents are currently using telemedicine. US surgeons were more likely to use telemedicine (p = 0.004). Surgeons believed telemedicine is useful for long-term/surveillance visits (70.2%, 80/114) but inappropriate (50.4%, 57/113) for new patient visits. CONCLUSION: COVID-19 pandemic resulted in increased use of neoadjuvant therapy, delays in operative procedures, and increased use of telemedicine. Telemedicine is perceived to be most efficacious for long-term/surveillance visits or postoperative visits.

KRAS Testing, Tumor Location, and Survival in Patients With Stage IV Colorectal Cancer: SEER 2010-2013.

Purpose:KRAS mutations and tumor location have been associated with response to targeted therapy among patients with stage IV colorectal cancer (CRC) in various trials. This study performed the first population-based examination of associations between KRAS mutations, tumor location, and survival, and assessed factors associated with documented KRAS testing. Methods: Patients with stage IV adenocarcinoma of the colon/rectum diagnosed from 2010 to 2013 were extracted from SEER data. Analyses of patient characteristics, KRAS testing, and tumor location were conducted using logistic regression. Cox proportional hazards models assessed relationships between KRAS mutations, tumor location, and risk of all-cause death. Results: Of 22,542 patients, 30% received KRAS testing, and 44% of these had mutations. Those tested tended to be younger, married, and metropolitan area residents, and have private insurance or Medicare. Rates of KRAS testing also varied by registry (range, 20%-46%). Patients with right-sided colon cancer (vs left-sided) tended to be older, female, and black; have mucinous, KRAS-mutant tumors; and have a greater risk of death (hazard ratio [HR], 1.27; 95% CI, 1.22-1.32). KRAS mutations were not associated with greater risk of death in the overall population; however, they were associated with greater risk of death among patients with left-sided colon cancer (HR, 1.19; 95% CI, 1.05-1.33). Conclusions: This large population-based study showed that among patients initially diagnosed with stage IV CRC, right-sided colon cancer was associated with greater risk of death compared with left-sided cancer, and KRAS mutations were only associated with risk of death in left-sided colon cancer. An unexpected finding was that among patients with stage IV disease, right-sided cancer was more commonly seen in black patients versus whites. Future studies should further explore these associations and determine the role of biology versus treatment differences. In addition, use of KRAS testing is increasing, but there is wide geographic variation wherein disparities related to insurance coverage and rurality may warrant further study.

Does Neoadjuvant Radiation Therapy Contribute to the Incidence of Pulmonary Complications Following Esophagectomy for Malignant Neoplasm?

BACKGROUND: Post-operative pulmonary complications (POPC) are common in patients undergoing esophagectomy and neoadjuvant radiotherapy may exacerbate POPC. This study assessed whether neoadjuvant radiation increases the incidence of POPC in patients undergoing esophagectomy for malignancy. METHODS: The American College of Surgeons-National Surgical Quality Improvement Program database files from 2016 to 2018 were queried for patients undergoing esophagectomy for malignancy. Inverse probability treatment weighting (IPTW) was used to create balanced cohorts in which the control group received neoadjuvant chemotherapy (nCT) and the treatment cohort received neoadjuvant chemoradiotherapy (nCRT). A subset analysis was performed on patients with pre-existing pulmonary disease (PEPD). Primary outcomes were POPC and 30-day mortality. RESULTS: The all-patient analysis did not demonstrate a consistent association between neoadjuvant radiation and POPC. However, in patients with PEPD, POPC occurred more often in the nCRT cohort. Comparing nCRT to nCT and after IPTW adjustment for confounders, there was higher odds of pneumonia (aOR = 3.0, P = .002), unplanned intubation (aOR = 2.0, P = .03), and extended mechanical ventilation (aOR = 3.6, P = .002). DISCUSSION: In esophageal cancer patients with PEPD that undergo nCRT vs nCT prior to esophagectomy, the greater risk of POPCs must be weighed against the potential for improved oncologic outcomes.

Neoadjuvant Therapy for Pancreatic Cancer: Increased Use and Improved Optimal Outcomes.

BACKGROUND: The introduction of more effective chemotherapy a decade ago has led to increased use of neoadjuvant therapy (NAT) in patients with pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to assess the evolving use of NAT in individuals with PDAC undergoing pancreatoduodenectomy (PD) and to compare their outcomes with patients undergoing upfront operation. STUDY DESIGN: The American College of Surgeons NSQIP Procedure Targeted Pancreatectomy database was queried from 2014 to 2019. Patients undergoing pancreatoduodenectomy were evaluated based on the use of NAT versus upfront operation. Multivariable analysis was performed to determine the effect of NAT on postoperative outcomes, including the composite measure optimal pancreatic surgery (OPS). Mann-Kendall trend tests were performed to assess the use of NAT and associated outcomes over time. RESULTS: A total of 13,257 patients were identified who underwent PD for PDAC between 2014 and 2019. Overall, 33.6% of patients received NAT. The use of NAT increased steadily from 24.2% in 2014 to 42.7% in 2019 (p < 0.0001). On multivariable analysis, NAT was associated with reduced serious morbidity (odds ratio [OR] 0.83, p < 0.001), clinically relevant pancreatic fistulas (OR 0.52, p < 0.001), organ space infections (OR 0.74, p < 0.001), percutaneous drainage (OR 0.73, p < 0.001), reoperation (OR 0.76, p = 0.005), and prolonged length of stay (OR 0.63, p < 0.001). OPS was achieved more frequently in patients undergoing NAT (OR 1.433, p < 0.001) and improved over time in patients receiving NAT (50.7% to 56.6%, p < 0.001). CONCLUSION: NAT before pancreatoduodenectomy increased more than 3-fold over the past decade and was associated with improved optimal operative outcomes.