Utility of Circulating Tumor DNA Assessment in Characterizing Recurrence Sites after Optimal Resection for Metastatic Colorectal Cancer.

INTRODUCTION: Plasma ctDNA is a promising biomarker for metastatic colorectal cancer (mCRC); however, its role in characterizing recurrence sites after mCRC resection remains poorly understood. This single-institution study investigated the timing of ctDNA detection and its levels in the context of recurrence at different sites following mCRC resection. METHODS: Patients who underwent optimal resection of CRC metastases involving the peritoneum, distant lymph nodes, or liver, with serial postoperative tumor-informed ctDNA assessments (Signatera) were included. Recurrence sites, as defined by surveillance imaging or laparoscopy, were categorized as peritoneal-only and other distant sites (liver, lung, lymph nodes, or body wall). RESULTS: Among the 31 included patients, ctDNA was detected in all 26 (83.4%) patients with postoperative recurrence and was persistently undetectable in five patients who did not experience recurrence. At three months post-surgery, ctDNA was detected in 2/8 (25.0%) patients with peritoneal-only recurrence and 17/18 (94.4%) patients with distant recurrence (p < 0.001). Beyond three months, ctDNA was detected in the remaining six patients with peritoneal-only disease and one patient with distant disease. ctDNA detection preceded the clinical diagnosis of recurrence by a median of nine weeks in both groups. At recurrence, peritoneal-only recurrent cases exhibited lower ctDNA levels (median 0.4 MTM/ml, IQR 0.1-0.8) compared to distant recurrence (median 5.5 MTM/ml, IQR 0.8-33.3, p = 0.004). CONCLUSION: Peritoneal-only recurrence was associated with delayed ctDNA detection and low levels of ctDNA after optimal resection for mCRC. ctDNA testing may effectively characterize recurrence sites and may help guide subsequent treatments specific to the disease sites involved.

A Novel Assessment of Metabolic Pathways in Peritoneal Metastases from Low-Grade Appendiceal Mucinous Neoplasms.

BACKGROUND: There is a paucity of targeted therapies for patients with pseudomyxoma peritonei (PMP) secondary to low-grade appendiceal mucinous neoplasms (LAMNs). Dysregulated metabolism has emerged as a hallmark of cancer, and the relationship of metabolomics and cancer is an area of active scientific exploration. We sought to characterize phenotypic differences found in peritoneal metastases (PM) derived from LAMN versus adenocarcinoma. METHODS: Tumors were washed with phosphate-buffered saline (PBS), microdissected, then dissociated in ice-cold methanol dried and reconstituted in pyridine. Samples were derivatized in tert-butyldimethylsilyl (TBDMS) and subjected to gas chromatography-coupled mass spectrometry. Metabolites were assessed based on a standard library. RNA sequencing was performed, with pathway and network analyses on differentially expressed genes. RESULTS: Eight peritoneal tumor samples were obtained and analyzed: LAMNs (4), and moderate to poorly differentiated adenocarcinoma (colon [1], appendix [3]). Decreases in pyroglutamate, fumarate, and cysteine in PM from LAMNs were found compared with adenocarcinoma. Analyses showed the differential gene expression was dominated by the prevalence of metabolic pathways, particularly lipid metabolism. The gene retinol saturase (RETSAT), downregulated by LAMN, was involved in the multiple metabolic pathways that involve lipids. Using network mapping, we found IL1B signaling to be a potential top-level modulation candidate. CONCLUSIONS: Distinct metabolic signatures may exist for PM from LAMN versus adenocarcinoma. A multitude of genes are differentially regulated, many of which are involved in metabolic pathways. Additional research is needed to identify the significance and applicability of targeting metabolic pathways in the potential development of novel therapeutics for these challenging tumors.

Management of colorectal cancer during the COVID-19 pandemic: Recommendations from a statewide multidisciplinary cancer collaborative.

COVID-19 has resulted in significant disruptions in cancer care. The Illinois Cancer Collaborative (ILCC), a statewide multidisciplinary cancer collaborative, has developed expert recommendations for triage and management of colorectal cancer when disruptions occur in usual care. Such recommendations would be applicable to future outbreaks of COVID-19 or other large-scale disruptions in cancer care.

Virtual Surgical Fellowship Recruitment During COVID-19 and Its Implications for Resident/Fellow Recruitment in the Future.

BACKGROUND: The COVID-19 pandemic has overlapped with the scheduled interview periods of over 20 surgical subspecialty fellowships, including the Complex General Surgical Oncology (CGSO) fellowships in the National Resident Matching Program and the Society of Surgical Oncology's Breast Surgical Oncology fellowships. We outline the successful implementation of and processes behind a virtual interview day for CGSO fellowship recruitment after the start of the pandemic. METHODS: The virtual CGSO fellowship interview process at the University of Chicago Medicine and NorthShore University Health System was outlined and implemented. Separate voluntary, anonymous online secure feedback surveys were email distributed to interview applicants and faculty interviewers after the interview day concluded. RESULTS: Sixteen of 20 interview applicants (80.0%) and 12 of 13 faculty interviewers (92.3%) completed their respective feedback surveys. Seventy-five percent (12/16) of applicants and all faculty respondents (12/12) stated the interview process was 'very seamless' or 'seamless'. Applicants and faculty highlighted decreased cost, time savings, and increased efficiency as some of the benefits to virtual interviewing. CONCLUSIONS: Current circumstances related to the COVID-19 pandemic require fellowship programs to adapt and conduct virtual interviews. Our report describes the successful implementation of a virtual interview process. This report describes the technical steps and pitfalls of organizing such an interview and provides insights into the experience of the interviewer and interviewee.

Academic productivity in surgical oncology: Where is the bar set for those training the next generation?

BACKGROUND AND OBJECTIVES: Promotion and tenure are important milestones for academic surgical oncologists. The aim of this study was to quantify academic metrics associated with rank in surgical oncologists training the next generation. METHODS: Faculty were identified from accredited surgical oncology fellowships in the United States. Scopus was used to obtain the number of publications/citations and h-index values. The National Institutes of Health (NIH) RePORT website was used to identify funding history. RESULTS: Of the 319 surgeons identified, complete rank information was obtained for 308. The majority of faculty were men (70%) and only 11% of full professors were women. The median h-index values were 7, 17, and 39 for assistant, associate, and full professors, respectively. While 50% of full professors had a history of NIH funding, only 26% had RO1s and 20% had current NIH funding. Using multivariate analysis, years in practice, h-index, and a history of NIH funding were associated with academic rank (P < .05). CONCLUSION: Objective benchmarks, such as the median h-index and NIH funding, provide additional insights for both junior faculty and leadership into the productivity needed to attain promotion to the next academic rank for surgical oncologists.

Safety and efficacy of LigaSure usage in pancreaticoduodenectomy.

BACKGROUND: Over recent years, use of the LigaSure™ vessel sealing device has increased in major abdominal surgery to include pancreaticoduodenectomy (PD). LigaSure™ use during PD has expanded to include all steps of the procedure, including the division of the uncinate margin. This introduces the potential for thermal major vascular injury or margin positivity. The aim of the present study was to evaluate the safety and efficacy of LigaSure™ usage in PD in comparison to established dissection techniques. METHODS: One hundred and forty-eight patients who underwent PD from 2007 to 2012 at Robert Wood Johnson University Hospital were identified from a retrospective database. Two groups were recognized: those in which the LigaSure™ device was used (N = 114), and in those it was not (N = 34). Peri-operative outcomes were compared. RESULTS: Vascular intra-operative complications directly caused by thermal injury from LigaSure™ use occurred in 1.8% of patients. Overall vascular intra-operative complications, uncinate margin positivity, blood loss, length of stay, and complication severity were not significantly different between groups. The mean operative time was 77 min less (P < 0.010) in the LigaSure™ group. Savings per case where the LigaSure™ was used amounted to $1776.73. CONCLUSION: LigaSure™ usage during PD is safe and effective. It is associated with decreased operative times, which may decrease operative costs in PD.