Extent of Resection and Long-Term Outcomes for Appendiceal Adenocarcinoma: a SEER Database Analysis of Mucinous and non-Mucinous Histologies.

BACKGROUND: Mucinous appendiceal adenocarcinomas (MAA) and non-mucinous appendiceal adenocarcinomas (NMAA) demonstrate differences in rates and patterns of recurrence, which may inform the appropriate extent of surgical resection (i.e., appendectomy versus colectomy). The impact of extent of resection on disease-specific survival (DSS) for each histologic subtype was assessed. PATIENTS AND METHODS: Patients with resected, non-metastatic MAA and NMAA were identified in the Surveillance, Epidemiology, and End Results database (2000-2020). Multivariable models were created to examine predictors of colectomy for each histologic subtype. DSS was calculated using Kaplan-Meier estimates and examined using Cox proportional hazards modeling. RESULTS: Among 4674 patients (MAA: n = 1990, 42.6%; NMAA: n = 2684, 57.4%), the majority (67.8%) underwent colectomy. Among colectomy patients, the rate of nodal positivity increased with higher T-stage (MAA: T1: 4.6%, T2: 4.0%, T3: 17.1%, T4: 21.6%, p < 0.001; NMAA: T1: 6.8%, T2: 11.4%, T3: 25.6%, T4: 43.8%, p < 0.001) and higher tumor grade (MAA: well differentiated: 7.7%, moderately differentiated: 19.2%, and poorly differentiated: 31.3%; NMAA: well differentiated: 9.0%, moderately differentiated: 20.5%, and 44.4%; p < 0.001). Nodal positivity was more frequently observed in NMAA (27.6% versus 16.4%, p < 0.001). Utilization of colectomy was associated with improved DSS for NMAA patients with T2 (log rank p = 0.095) and T3 (log rank p = 0.018) tumors as well as moderately differentiated histology (log rank p = 0.006). Utilization of colectomy was not associated with improved DSS for MAA patients, which was confirmed in a multivariable model for T-stage, grade, and use of adjuvant chemotherapy [hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.81-1.22]. CONCLUSIONS: Colectomy was associated with improved DSS for patients with NMAA but not MAA. Colectomy for MAA may not be required.

Pancreatectomy for intraductal papillary mucinous neoplasm: has anything changed in North America?

BACKGROUND: Multiple guidelines on the management of intraductal papillary mucinous neoplasm (IPMN) have been published over the past decade. However, practice data are lacking. This study aims to determine whether pancreatectomy procedures, IPMN pathology, or outcomes have changed. METHODS: ACS-NSQIP Procedure Targeted Pancreatectomy database was queried for patients with IPMN from 2014 to 2019. Cases were stratified by pathology, tumor stage/cyst size and procedure. Pancreatectomies for IPMN by year, 30-day morbidity, and clinically relevant postoperative pancreatic fistula (CR-POPF) were quantified. Mann-Kendall trend tests were performed to assess surgical trends and associated outcomes over time. RESULTS: 3912 patients underwent pancreatectomy for IPMN. 21% demonstrated malignancy and 79% were benign. Morbidity and mortality occurred in 29.7% and 1.5% of cases, respectively. Over time, no change was observed in use of pancreatectomy for IPMN (10%) or in benign/malignant pathology, or cyst size. Robotic approach increased from 9.1% to 16.5% with decreases in laparoscopic (19.5%-15.0%) and open interventions (71.5%-68.1%, p = 0.016). No change was observed over time in morbidity or mortality; however, rates of CR-POPF decreased (18.8%-13.8%, p < 0.001). CONCLUSIONS: Practice patterns in treatment of IPMN have not changed significantly in North America. More patients are undergoing robotic pancreatectomy, and postoperative pancreatic fistula rates are improving.

Robotic pancreatoduodenectomy: trends in technique and training challenges.

BACKGROUND: More complex cases are being performed robotically. This study aims to characterize trends in robotic pancreatoduodenectomy (RPD) over time and assess opportunities for advanced trainees. METHODS: Using the ACS-NSQIP database from 2014 to 2019, PD cases were characterized by operative approach (open-OPN, laparoscopic-LAP, robotic-ROB). Proficiency and postoperative outcomes were described by approach over time. RESULTS: 24,268 PDs were identified, with the ROB approach increasing from 2.8% to 7.5%. Unplanned conversion increased over time for LAP (27.7-39.0%, p = 0.003) but was unchanged for ROB cases (14.8-14.7%, p = 0.257). Morbidity increased for OPN PD (35.5-36.8%, p = 0.041) and decreased for ROB PD (38.7-30.3%, p = 0.010). Mean LOS was lower in ROB than LAP/OPN (9.5 vs. 10.9 vs. 10.9 days, p < 0.00001). Approximately, 100 AHPBA, SSO, and ASTS fellows are being trained each year in North America; however, only about 5 RPDs are available per trainee per year which is far below that recommended to achieve proficiency. CONCLUSION: Over a 6-year period, a significant increase was observed in the use of RPD without a concomitant increase in conversion rates. RPD was associated with decreased morbidity and length of stay. Despite this shift, the number of cases being performed is not adequate for all fellows to achieve proficiency before graduation.

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.

Locoregional Liver-Directed Therapies to Treat Unresectable Colorectal Liver Metastases: A Review

An estimated 70% of patients with colorectal cancer will develop liver metastases during the course of their disease. While the first-line treatment for hepatic metastases is resection, most patients with colorectal liver-only or liver-dominant metastases (CRLM) present with unresectable disease and are not surgical candidates. In the past decade, locoregional liver-directed therapies have demonstrated safety and efficacy in the treatment of patients with unresectable CRLM and chemotherapy-refractory disease. These treatments can be used to attempt conversion to surgical resectability, can control local disease progression, and have the potential to prolong survival. However, they have not yet become the standard of care in many practices. Each treatment has unique risks, and the clinical data are heterogeneous and thus difficult to interpret. In this article, we will review the most recent, high-impact literature on 3 common locoregional therapies used in the treatment of patients with unresectable CRLM: hepatic artery infusion pump chemotherapy, stereotactic body radiation therapy, and selective internal radiation therapy with yttrium-90 embolization. Ultimately, for this patient population, clinical decision-making requires a multidisciplinary discussion which should take into account individual patient characteristics and clinical expertise available at the treatment facility.

Impact of postoperative complications on long-term survival after esophagectomy in older adults: A SEER-Medicare analysis.

BACKGROUND: Esophagectomy is a complex procedure associated with a high rate of postoperative complications. It is not clear whether postoperative complications effect long-term survival. Most studies report the results from single institutions. METHODS: We examined the Surveillance, Epidemiology and End Results (SEER)-Medicare database to assess whether long-term overall and cancer-specific mortality of patients undergoing esophagectomy for cancer is impacted by postoperative complications. RESULTS: Nine hundred and forty patients underwent esophagectomy from 2007 to 2014, of which 50 died, resulting in a cohort of 890 patients. Majority were males (n = 764, 85.8%) with adenocarcinoma of the lower esophagus. Almost 60% of the group had no neoadjuvant therapy. Four hundred and fifty-five patients had no major complications (51.1%), while 285 (32.0%) and 150 (16.9%) patients had one, two, or more major complications, respectively. Overall survival at 90 days was 93.1%. Multivariate analysis of patients followed up for a minimum of 90 days demonstrated that the number of complications was significantly associated with decreased overall survival but no impact on cancer-specific survival. CONCLUSIONS: Our population-based analysis with its inherent limitations suggests that patients undergoing esophagectomy who experience complications have worse overall survival but not cancer-specific survival if they survive at least 90 days from the date of surgery.

Outcomes Following Major Oncologic Operations for Non-AIDS-Defining Cancers in the HIV Population: A Matched Comparison to the General Population.

INTRODUCTION: Human immunodeficiency virus (HIV) patients are living longer due to the availability of antiretroviral therapies, and non-AIDS-defining cancers are becoming more prevalent in this patient population. A paucity of data remains on post-operative outcomes following resection of non-AIDS-defining cancers in the HIV population. METHODS: The National Inpatient Sample was utilized to identify patients who underwent surgical resection for malignancy from 2005 to 2015 (HIV, N = 52,742; non-HIV, N = 11,885,184). Complications were categorized by international classification of disease (ICD)-9 diagnosis codes. Cohorts were matched on insurance, household income, zip code and urban/rural setting. Logistic regression assessed whether HIV was an independent predictor of post-operative complications. RESULTS: Descriptive statistics found HIV patients to have an increased rate of complications following select oncologic surgical resections. Univariate and multivariate logistic regression found HIV to only be an independent predictor of complications following pulmonary lobectomy (p = 0.011; OR 2.93, 95% CI 1.29-6.73). Length of stay was statistically longer following colectomy (2.61 days, 95% CI 1.98-3.44) in those with HIV. CONCLUSIONS: Our findings are hypothesis generating and highlight the potential safety of major cancer surgery in the HIV population. However, care providers need be cognizant of the potential increased risk of post-operative complications following pulmonary lobectomy and the potential for increased length of stay. These findings are an initial insight into quality of care and outcomes metrics on HIV patients undergoing major cancer operations.

Elevated Blood Neutrophil-to-Lymphocyte Ratio: A Readily Available Biomarker Associated with Death due to Disease in High Risk Nonmetastatic Melanoma.

BACKGROUND: Elevated peripheral blood neutrophil-to-lymphocyte ratio (NLR) is associated with poor oncologic outcomes in patients with stage IV melanoma and other solid tumors, but its impact has not been characterized for patients with high-risk, nonmetastatic melanoma. METHODS: Retrospective review of a melanoma database identified patients with high-risk melanoma who underwent operation with curative intent at a single institution. NLR was calculated from blood samples obtained within 2 weeks before operation. Multiple primary melanomas and concurrent hematologic or other metastatic malignancies were excluded. Cumulative incidence of death due to disease was estimated, and Gray's test was used to examine the effect of NLR on melanoma disease-specific death (DOD). Multivariable competing risks regression models assessed associated factors. RESULTS: Data on 1431 patients with high-risk, nonmetastatic melanoma were analyzed. Median follow-up for survivors was 4 years. High NLR (≥3 or as continuous variable) was associated with older age, male sex, thicker primaries, higher mitotic index, and more advanced nodal status. On multivariate analysis, high NLR (≥3 or as a continuous variable), older age, male sex, ulcerated primary, lymphovascular invasion, and positive nodal status were all independently associated with worse DOD. CONCLUSIONS: NLR is a readily available blood test that was independently associated with DOD in patients with high-risk, nonmetastatic melanoma. It is unclear whether high NLR is a passive indicator of poor prognosis or a potential therapeutic target. Further studies to evaluate the prognostic role of NLR to potentially identify those more likely to benefit from adjuvant immunotherapy may prove informative.

Recurrence patterns following irreversible electroporation for hepatic malignancies.

BACKGROUND: Irreversible electroporation (IRE) has emerged as a novel, safe ablative therapy for peri-vascular lesions. However, there remains a paucity of data on long-term outcomes. METHODS: We identified patients who underwent open IRE (1/2011-6/2015) for primary and secondary hepatic malignancies. Local ablation-zone recurrence (LR) was determined by cross-sectional imaging. Cumulative incidence (CumI) of LR was calculated and a competing risks regression assessed factors associated with LR. RESULTS: Forty patients had 77 lesions treated. The majority of lesions were of colorectal origin (74%). Median tumor size was 1.3 cm (range 0.5-6). Most patients (86%) had prior systemic therapy and 29% received systemic therapy following IRE. With a median follow-up of 25.7 months (range 4.5-58.8 months), 10 lesions in 9 patients recurred locally (CumI: 13.4%, 95%CI: 7.8-22.2%). Median estimated time to LR was not reached and no LR occurred after 19 months. Factors significantly associated with LR included ablation zone size (HR 1.58; 95%CI 1.12-2.23; P = 0.0093) and body mass index (HR 1.21 95%CI 1.10-1.34; P = 0.0001). CONCLUSION: IRE LR rates were low after the treatment of well selected, small tumors. This technique is useful for lesions in anatomic locations precluding resection or thermal ablation.

Impact of maximal cytoreductive surgery plus regional heated intraperitoneal chemotherapy (HIPEC) on outcome of patients with peritoneal carcinomatosis of gastric origin: results of the GYMSSA trial.

BACKGROUND: A prospective randomized trial was conducted to compare the impact of systemic chemotherapy versus multi-modality therapy (complete cytoreductive surgery (CRS), hyperthermic intraperitoneal chemotherapy (HIPEC), and systemic chemotherapy) on overall survival (OS) in patients with gastric carcinomatosis. METHODS: Patients with measurable metastatic gastric adenocarcinoma involving the peritoneum, and resectable to "no evidence of disease" were randomized to gastrectomy, metastasectomy, HIPEC, and systemic FOLFOXIRI (GYMS arm) or FOLFOXIRI alone (SA arm). RESULTS: Seventeen patients were enrolled (16 evaluable); 7 of 9 patients in the multi-modality GYMS arm achieved complete cytoreduction (CCR0). Median OS was 11.3 months in the GYMS arm and 4.3 months in the SA arm. Four patients in the GYMS arm survived >12 months, 2 patients close to 2 years at last follow-up, and 1 patient more than 4 years, with 2 of these patients still alive. No patient in the SA arm lived beyond 11 months. All patients surviving beyond 12 months in the surgery arm achieved complete cytoreduction and had an initial Peritoneal Cancer Index (PCI) of ≤ 15. CONCLUSION: Maximal cytoreductive surgery combined with regional (HIPEC) and systemic chemotherapy in selected patients with gastric carcinomatosis and limited disease burden can achieve prolonged survival.

Label-retaining liver cancer cells are relatively resistant to sorafenib.

OBJECTIVE: The standard therapy for advanced hepatocellular carcinoma (HCC) is sorafenib, with most patients experiencing disease progression within 6 months. Label-retaining cancer cells (LRCC) represent a novel subpopulation of cancer stem cells (CSC). The objective was to test whether LRCC are resistant to sorafenib. METHODS: We tested human HCC derived LRCC and non-LRCC before and after treatment with sorafenib. RESULTS: LRCC derived from human HCC are relatively resistant to sorafenib. The proportion of LRCC in HCC cell lines is increased after sorafenib while the general population of cancer cells undergoes growth suppression. We show that LRCC demonstrate improved viability and toxicity profiles, and reduced apoptosis, over non-LRCC. We show that after treatment with sorafenib, LRCC upregulate the CSC marker aldehyde dehydrogenase 1 family, wingless-type MMTV-integration-site family, cell survival and proliferation genes, and downregulate apoptosis, cell cycle arrest, cell adhesion and stem cells differentiation genes. This phenomenon was accompanied by non-uniform activation of specific isoforms of the sorafenib target proteins extracellular-signal-regulated kinases and v-akt-murine-thymoma-viral-oncogene homologue (AKT) in LRCC but not in non-LRCC. A molecular pathway map for sorafenib treated LRCC is proposed. CONCLUSIONS: Our results suggest that HCC derived LRCC are relatively resistant to sorafenib. Since LRCC can generate tumours with as few as 10 cells, our data suggest a potential role for these cells in disease recurrence. Further investigation of this phenomenon might provide novel insights into cancer biology, cancer recurrence and drug resistance with important implications for the development of novel cancer therapies based on targeting LRCC.

Operative trends for pancreatic and hepatic malignancies during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic disrupted routine health care, including many elective and non-cancer operations in the United States. Most hepato-pancreato-biliary malignancy patients require outpatient imaging, tissue sampling, and staging, and many undergo neoadjuvant therapy before operative intervention. The aims of this study were to evaluate the effect of the COVID-19 pandemic on hepato-pancreato-biliary oncologic operations and to determine whether trends in neoadjuvant therapy were altered by the pandemic. METHODS: Adult patients in the United States undergoing oncologic operations for pancreatic, primary and secondary hepatic malignancies, with or without neoadjuvant therapy, were extracted from the Vizient Clinical Data Base. Control chart analysis was used to plot trends over time and to determine whether changes were statistically significant. Wilcoxon rank-sum tests also compared monthly operative volume from pre-pandemic (12 month) and pandemic (28 months) periods. RESULTS: A total of 36,553 patients were identified over 40 months. Mean monthly pancreatic oncologic operations were unaffected by the pandemic (P = .257). Operations for pancreatic oncologic operations with prior neoadjuvant therapy increased throughout the pandemic (P = .002). Oncologic operations for primary and secondary hepatic malignancies were significantly reduced for 4 and 2 months, respectively, at the beginning of the pandemic but returned to their pre-pandemic baseline within 4 months (P = .169 and P = .598). CONCLUSION: Pancreatic operation volumes for cancer did not change, but pancreatic operations after neoadjuvant therapy continued to increase during the pandemic. Operations for hepatic malignancy were transiently disrupted but quickly normalized. These observations suggest that surgery for hepato-pancreato-biliary malignancies was prioritized during the pandemic.

Recurrence-free survival dynamics following adjuvant chemotherapy for resected colorectal cancer: A systematic review of randomized controlled trials.

BACKGROUND: Several cytotoxic chemotherapies have demonstrated efficacy in improving recurrence-free survival (RFS) following resection of Stage II-IV colorectal cancer (CRC). However, the temporal dynamics of response to such adjuvant therapy have not been systematically quantified. METHODS: The Cochrane Central Register of Trials, Medline (PubMed) and Web of Science were queried from database inception to February 23, 2023 for Phase III randomized controlled trials (RCTs) where there was a significant difference in RFS between adjuvant chemotherapy and surgery only arms. Summary data were extracted from published Kaplan-Meier curves using DigitizeIT. Absolute differences in RFS event rates were compared at matched intervals using multiple paired t-tests. RESULTS: The initial search yielded 1469 manuscripts. After screening, 18 RCTs were eligible (14 Stage II/III; 4 Stage IV), inclusive of 16,682 patients. In the absence of adjuvant chemotherapy, the greatest rate of recurrence was observed in the first year (mean RFS event rate; 0-0.5 years: 0.22 ± 0.21; 0.5-1 years: 0.20 ± 0.09). Adjuvant chemotherapy was associated with significant decreases in the RFS event rates for the intervals 0-0.5 years (0.09 ± 0.09 vs. 0.22 ± 0.21, p < 0.001) and 0.5-1 years (0.14 ± 0.11 vs. 0.20 ± 0.09, p = 0.001) after randomization, but not at later intervals (1-5 years). In Stage IV trials, RFS event rates significantly differed for the interval 0-0.5 years (p = 0.012), corresponding with adjuvant treatment durations of 6 months. In Stage II/III trials, which included therapies of 6-24 months duration, there were marked differences in the RFS event rates between surgery and chemotherapy arms for the intervals 0-0.5 years (p < 0.001) and 0.5-1 years (p < 0.001) with smaller differences in the RFS event rates for the intervals 1-2 years (p = 0.012) and 2-3 years (p = 0.010). CONCLUSIONS: In a systematic review of positive RCTs comparing adjuvant chemotherapy to surgery alone for Stage II-IV CRC, observed RFS improvements were driven by early divergences that occurred primarily during active cytotoxic chemotherapy. Late recurrence dynamics were not influenced by adjuvant therapy use. Such observations may have implications for the use of chemotherapy for micrometastatic clones detectable by cell-free DNA-based methodologies.

Racial disparities in rates of invasiveness of resected intraductal papillary mucinous neoplasms in the United States.

BACKGROUND: Racial and ethnic disparities have been observed in the multidisciplinary management of pancreatic ductal adenocarcinoma. Intraductal papillary mucinous neoplasm is the most common identifiable precursor to pancreatic ductal adenocarcinoma, where early surgical intervention before the development of an invasive intraductal papillary mucinous neoplasm improves survival. The association of race/ethnicity with the risk of identifying invasive intraductal papillary mucinous neoplasms during resection has not been previously defined. METHODS: The American College of Surgeons National Quality Improvement Program targeted pancreatectomy database (2014-2021) was queried for patients with race/ethnicity data who underwent resection of an intraductal papillary mucinous neoplasm. Backward Wald logistic regression modeling (P ≤ 0.05 for entry; P > .10 for removal) was used to identify independent predictors of invasion. RESULTS: A total of 4,505 cases of resected intraductal papillary mucinous neoplasms were identified, with 923 (20.5%) demonstrating invasive intraductal papillary mucinous neoplasms. The cohort of individuals other than non-Hispanic Whites were significantly more likely to have invasive intraductal papillary mucinous neoplasms (White, 19.9%; Black, 24.2%; Asian, 23.7%; Hispanic, 22.6%; P = .026). Such disparity could not be explained by greater comorbidity, as non-White patients were significantly younger (age <65 years: 41.7% vs 33.2%, P < .001) and had better physical status (American Society of Anesthesiologists score ≤2: 28.8% vs 25.2%, P = .053). After controlling for clinicodemographic variables, being an individual of race/ethnicity other than White was independently associated with higher odds of invasive intraductal papillary mucinous neoplasms (odds ratio, 1.280; 95% confidence interval, 1.046-1.566; P = .017). No differences in postoperative morbidity were observed. CONCLUSION: In a national cohort of patients with resected intraductal papillary mucinous neoplasms, individuals who identified as being of race/ethnicity other than White were significantly more likely to have invasive intraductal papillary mucinous neoplasms during surgical resection.

Ampullary Adenocarcinoma: A Review of the Mutational Landscape and Implications for Treatment.

Ampullary carcinomas represent less than 1% of all gastrointestinal malignancies with an incidence of approximately 6 cases per 1 million. Histologic examination and immunohistochemistry have been traditionally used to categorize ampullary tumors into intestinal, pancreatobiliary or mixed subtypes. Intestinal-subtype tumors may exhibit improved survival versus the pancreatobiliary subtype, although studies on the prognostic value of immunomorphologic classification have been inconsistent. Genomic classifiers hold the promise of greater reliability, while providing potential targets for precision oncology. Multi-institutional collaboration will be necessary to better understand how molecular classification can guide type and sequencing of multimodality therapy.

Hepatic pseudotumor associated with Strongyloides infection: A case report.

BACKGROUND: Strongyloides sterocoralis is a parasitic infection caused by a roundworm that is transmitted through soil contaminated with larvae. It can infrequently cause hepatic abscesses in immunocompromised patients and is rarely reported to form hepatic lesions in immunocompetent hosts. CASE SUMMARY: We present a case study of a 45-year-old female who presented with right upper quadrant abdominal pain and constitutional symptoms for several weeks. Cross-sectional imaging identified several malignant-appearing liver masses. Further investigation, including serological testing and histopathologic examination, revealed the presence of serum Strongyloides antibodies and hepatic granulomas with extensive necrosis. Following treatment with ivermectin for 2 wk, there was complete resolution of the liver lesions and associated symptoms. CONCLUSION: This case highlights the importance of considering parasitic infections, such as Strongyloides, in the differential diagnosis of hepatic masses. Early recognition and appropriate treatment can lead to a favorable outcome and prevent unnecessary invasive procedures. Increased awareness among clinicians is crucial to ensure the timely diagnosis and management of such cases.

Association between SMAD4 Mutations and GATA6 Expression in Paired Pancreatic Ductal Adenocarcinoma Tumor Specimens: Data from Two Independent Molecularly-Characterized Cohorts.

Several molecular biomarkers have been identified to guide induction treatment selection for localized pancreatic ductal adenocarcinoma (PDAC). SMAD4 alterations and low GATA6 expression/modified "Moffitt" basal-like phenotype have each been associated with inferior survival uniquely for patients receiving 5-FU-based therapies. SMAD4 may directly regulate the expression of GATA6 in PDAC, pointing to a common predictive biomarker. To evaluate the relationship between SMAD4 mutations and GATA6 expression in human PDAC tumors, patients with paired SMAD4 mutation and GATA6 mRNA expression data in the TCGA and CPTAC were identified. In 321 patients (TCGA: n = 180; CPTAC: n = 141), the rate of SMAD4 alterations was 26.8%. The rate of SMAD4 alteration did not vary per tertile of normalized GATA6 expression (TCGA: p = 0.928; CPTAC: p = 0.828). In the TCGA, SMAD4 alterations and the basal-like phenotype were each associated with worse survival (log rank p = 0.077 and p = 0.080, respectively), but their combined presence did not identify a subset with uniquely inferior survival (p = 0.943). In the CPTAC, the basal-like phenotype was associated with significantly worse survival (p < 0.001), but the prognostic value was not influenced by the combined presence of SMAD4 alterations (p = 0.960). SMAD4 alterations were not associated with poor clinico-pathological features such as poor tumor grade, advanced tumor stage, positive lymphovascular invasion (LVI), or positive perineural invasion (PNI), compared with SMAD4-wildtype. Given that SMAD4 mutations were not associated with GATA6 expression or Moffitt subtype in two independent molecularly characterized PDAC cohorts, distinct biomarker-defined clinical trials are necessary.

COVID-19 Effect on Surgery for Gastrointestinal Malignancies: Have Operative Volumes Recovered?

BACKGROUND: COVID-19 disrupted elective operations, cancer screening, and routine medical care while simultaneously overwhelming hospital staff and supplies. Operations for gastrointestinal (GI) malignancies rely on endoscopic screening, staging, and neoadjuvant therapy (NAT), each of which was disrupted by the pandemic. The aim was to evaluate the effect of the COVID-19 pandemic on the US national rates of gastrointestinal oncologic operations. METHODS: The Vizient Clinical Data Base® was queried for oncologic operations for esophageal, gastric, and colorectal malignancies with and without NAT from March 2019 to March 2022. Control chart analysis examined operative volume over time while Wilcoxon rank sum tests were used to compare mean monthly volume before and during the pandemic. RESULTS: A total of 95,912 patients were identified over 36 months; 5.8% esophageal, 6.3% gastric, 77.5% colonic, and 10.4% rectal operations. Esophageal operative volume decreased for 9 months during the pandemic and was significantly lower during than before the pandemic (p=0.002). Gastric operations decreased for 10 months early in the pandemic, but rebounded so that after 2 years volumes were unchanged (p=0.49). Colonic operations experienced a sharp decrease for 4 months at the beginning of the pandemic, but volumes quickly increased and overall were unchanged (p=0.29). Rectal operations decreased for 13 months and were significantly lower during than before the pandemic (p=0.018). Oncologic operations for patients receiving NAT varied. CONCLUSION: COVID-19 significantly disrupted the volume of gastrointestinal oncologic operations in the USA. Esophageal and rectal oncologic operations experienced prolonged and significant reductions while gastric and colonic oncologic operations transiently decreased but rebounded during the pandemic.

Combination of Immunotherapy and Radiation Therapy in Gastrointestinal Cancers: An Appraisal of the Current Literature and Ongoing Research.

Oncological outcomes are improving in gastrointestinal cancer with advancements in systemic therapies, and there is notable potential in combining immunotherapy and radiation therapy (RT) to allow for further improvements. Various preclinical and early phase II studies have shown promising synergy with immunotherapy and RT in gastrointestinal cancer. A few recent phase III studies have shown improved survival with the addition of immunotherapy to standard treatment for gastrointestinal cancer. The timing, duration, sequencing, and integration with other anti-cancer treatments are still areas of ongoing research. We have reviewed the published and ongoing studies of the combinations of immunotherapy and RT in gastrointestinal cancers.