Preoperative CA 19-9 Predicts Disease Progression in Colorectal Peritoneal Metastases Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: An Analysis from the US HIPEC Collaborative

INTRODUCTION

Patients with colorectal peritoneal metastases (CRPM) are increasingly treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Unfortunately, data identifying preoperative risk factors for poor oncologic outcomes after this procedure are limited. We aimed to determine the prognostic value of preoperative CEA, CA 125, and CA 19-9 on disease progression after CRS/HIPEC.

METHODS

Patients with CRPM treated with curative intent CRS/HIPEC from 12 participating sites in the United States from 2000 to 2017 were identified. Progression-free survival (PFS), defined as disease progression or recurrence, was the primary outcome.

RESULTS

In 279 patients who met inclusion criteria, the rate of disease progression was 63.8%, with a median PFS of 11 months (interquartile range [IQR] 5-20). Elevated CA 19-9 was associated with dismal PFS at 2 years (8.9% elevated vs. 30% not elevated, p < 0.01). In 113 patients who underwent upfront CRS/HIPEC, CA 19-9 emerged as the sole tumor marker independently predictive of worse PFS (hazard ratio [HR] 2.88, p = 0.048). In the subgroup of patients who had received neoadjuvant therapy (NAT), no variable was independently predictive of PFS. CA 19-9 levels over 37 U/ml were highly specific for accelerated disease progression after CRS/HIPEC. Lastly, there was no association between PFS and elevated CEA or CA 125.

CONCLUSIONS

Elevated CA 19-9 is associated with decreased PFS in patients with CRPM. While traditionally CEA is the main tumor marker assessed in colon cancer, we found that CA 19-9 may better inform preoperative risk stratification for poor oncologic outcomes in patients with CRPM. However, prospective studies are required to confirm this association.

Initial Experience Using Laparoscopic HIPEC for Gastric Cancer with Peritoneal Metastasis: Safety and Outcomes

BACKGROUND

Peritoneal metastases (PM) develop in approximately 20% of patients with gastric cancer (GC). For selected patients, treatment of PM with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has shown promising results. This report aims to describe the safety and perioperative outcomes of laparoscopic HIPEC for GC/PM.

METHODS

This retrospective cohort study evaluated patients who had GC and PM treated with laparoscopic HIPEC (2018-2022). The HIPEC involved cisplatin and mitomycin C (MMC) or MMC alone. The primary end point was perioperative safety.

RESULTS

The 22 patients in this study underwent 27 procedures. The mean age was 58 ± 13 years. All the patients were Eastern Cooperative Oncology Group (ECOG) 0 or 1 (55 and 45%, respectively). Five patients underwent a second laparoscopic HIPEC, with a median of 126 days (interquartile range [IQR], 117-166 days) between procedures. The median peritoneal carcinomatosis index (PCI) was 4 (IQR, 2-9), and the median hospital stay was 2 days (IQR, 1-3 days). No 30-day readmissions or complications occurred. Eight patients (36%) underwent gastrectomy (CRS ± HIPEC). After an average follow-up period of 11 months, 7 (32%) of the 22 patients were alive. The median overall survival was 11 months (IQR, 195-739 days) from the initial procedure and 19.3 months (IQR, 431-1204 days) from the diagnosis.

CONCLUSIONS

Laparoscopic HIPEC appears to be safe with minimal perioperative complications. Approximately one third of the patients undergoing initial laparoscopic HIPEC ultimately proceeded to cytoreduction and gastrectomy. Preliminary survival data from this highly selected cohort suggest that the addition of laparoscopic HIPEC to systemic chemotherapy does not compromise other treatment options. These initial results suggest that laparoscopic HIPEC may offer benefit to patients with GC and PM and aid in the selection of patients who may benefit from curative-intent resection.

Perceptions of Readiness for Practice After Complex General Surgical Oncology Fellowship: A Survey Study

BACKGROUND

Surgical subspecialty training aims to meet the needs of practicing surgeons and their communities. This study investigates career preparedness of Complex General Surgical Oncology (CGSO) fellowship graduates, identifies factors associated with practice readiness, and explores potential opportunities to improve the current training model.

METHODS

The Society of Surgical Oncology partnered with the National Cancer Institute to conduct a 36-question survey of CGSO fellowship graduates from 2012 to 2022.

RESULTS

The overall survey response rate was 38% (221/582) with a slight male predominance (63%). Forty-six percent of respondents completed their fellowship after 2019. Factors influencing fellowship program selection include breadth of cancer case exposure (82%), mentor influence (66%), and research opportunities (38%). Overall, graduates reported preparedness for practice; however, some reported unpreparedness in research (18%) and in specific clinical areas: thoracic (43%), hyperthermic intraperitoneal chemotherapy (HIPEC) (15%), and hepato-pancreato-biliary (15%) surgery. Regarding technical preparedness, 70% reported being "very prepared". Respondents indicated lack of preparedness in robotic (63%) and laparoscopic (33%) surgery approaches. Suggestions for training improvement included increased autonomy and case volumes, program development, and research infrastructure. Current practice patterns by graduates demonstrated discrepancies between ideal contracts and actual practice breakdowns, particularly related to the practice of general surgery.

CONCLUSIONS

This study of CGSO fellowship graduates demonstrates potential gaps between trainee expectations and the realities of surgical oncology practice. Although CGSO fellowship appears to prepare surgeons for careers in surgical oncology, there may be opportunities to refine the training model to better align with the needs of practicing surgical oncologists.

Neighborhood-Level Socioeconomic Disadvantage Predicts Outcomes in Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Malignancy

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) improves survival in select patients with peritoneal metastases (PM), but the impact of social determinants of health on CRS/HIPEC outcomes remains unclear.

PATIENTS AND METHODS

A retrospective review was conducted of a multi-institutional database of patients with PM who underwent CRS/HIPEC in the USA between 2000 and 2017. The area deprivation index (ADI) was linked to the patient's residential address. Patients were categorized as living in low (1-49) or high (50-100) ADI residences, with increasing scores indicating higher socioeconomic disadvantage. The primary outcome was overall survival (OS). Secondary outcomes included perioperative complications, hospital/intensive care unit (ICU) length of stay (LOS), and disease-free survival (DFS).

RESULTS

Among 1675 patients 1061 (63.3%) resided in low ADI areas and 614 (36.7%) high ADI areas. Appendiceal tumors (n = 1102, 65.8%) and colon cancer (n = 322, 19.2%) were the most common histologies. On multivariate analysis, high ADI was not associated with increased perioperative complications, hospital/ICU LOS, or DFS. High ADI was associated with worse OS (median not reached versus 49 months; 5 year OS 61.0% versus 28.2%, P < 0.0001). On multivariate Cox-regression analysis, high ADI (HR, 2.26; 95% CI 1.13-4.50; P < 0.001), cancer recurrence (HR, 2.26; 95% CI 1.61-3.20; P < 0.0001), increases in peritoneal carcinomatosis index (HR, 1.03; 95% CI 1.01-1.05; P < 0.001), and incomplete cytoreduction (HR, 4.48; 95% CI 3.01-6.53; P < 0.0001) were associated with worse OS.

CONCLUSIONS

Even after controlling for cancer-specific variables, adverse outcomes persisted in association with neighborhood-level socioeconomic disadvantage. The individual and structural-level factors leading to these cancer disparities warrant further investigation to improve outcomes for all patients with peritoneal malignancies.

A call for standardized reporting of early-onset colorectal peritoneal metastases

BACKGROUND

The incidence of colorectal cancer (CRC) in patients under 50 years of age, i.e., early-onset CRC, has increased in the past two decades. Colorectal peritoneal metastases (CPM) will develop in 10-30% of CRC patients. CPM traditionally had a dismal prognosis, but surgery and novel systemic treatments appear to increase survival. Determining potential age-associated risk and prognostic factors is optimized when analyses use standardized age groupings.

METHODS

We performed a review of early-onset CPM studies and compared variables used, e.g., age stratification and definitions of synchronous and metachronous CPM. We included studies published in PubMed up to November 2022 if results were stratified by age.

RESULTS

Of 114 screened publications in English, only 10 retrospective studies met inclusion criteria. Incidence of CPM was higher in younger CRC patients (e.g. 23% vs. 2% for <25 vs. ≥25 years, P < 0.0001; and 57% vs. 39% vs. 4% for <20 vs. 20-25 vs. >25 years, P < 0.001); two studies reported higher proportion of younger African American CPM patients (e.g. 16% vs. 6% for <50 vs. ≥50 years). Studies used seven different age-stratification methods, presenting comparison challenges.

CONCLUSION

Studies showed a higher proportion of CPM in younger patients, but directly comparing results was not possible due to inconsistent reporting. To better address this issue, CRC and CPM studies stratified by standard age groups (e.g. <50 vs. ≥50) are needed.

Validation of the AJCC 8th Edition Staging System for Disseminated Appendiceal Cancer Patients Treated with Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy: A Multi-institutional Analysis

BACKGROUND

The AJCC 8th edition stratifies stage IV disseminated appendiceal cancer (dAC) patients based on grade and pathology. This study was designed to externally validate the staging system and to identify predictors of long-term survival.

METHODS

A 12-institution cohort of dAC patients treated with CRS ± HIPEC was retrospectively analyzed. Overall survival (OS) and recurrence-free survival (RFS) were analyzed by using Kaplan-Meier and log-rank tests. Univariate and multivariate cox-regression was performed to assess factors associated with OS and RFS.

RESULTS

Among 1009 patients, 708 had stage IVA and 301 had stage IVB disease. Median OS (120.4 mo vs. 47.2 mo) and RFS (79.3 mo vs. 19.8 mo) was significantly higher in stage IVA compared with IVB patients (p < 0.0001). RFS was greater among IVA-M1a (acellular mucin only) than IV M1b/G1 (well-differentiated cellular dissemination) patients (NR vs. 64 mo, p = 0.0004). Survival significantly differed between mucinous and nonmucinous tumors (OS 106.1 mo vs. 41.0 mo; RFS 46.7 mo vs. 21.2 mo, p < 0.05), and OS differed between well, moderate, and poorly differentiated (120.4 mo vs. 56.3 mo vs. 32.9 mo, p < 0.05). Both stage and grade were independent predictors of OS and RFS on multivariate analysis. Acellular mucin and mucinous histology were associated with better OS and RFS on univariate analysis only.

CONCLUSIONS

AJCC 8th edition performed well in predicting outcomes in this large cohort of dAC patients treated with CRS ± HIPEC. Separation of stage IVA patients based on the presence of acellular mucin improved prognostication, which may inform treatment and long-term, follow-up strategies.

Tumor Regression Grade and Overall Survival following Gastrectomy with Preoperative Therapy for Gastric Cancer

BACKGROUND

Pre-/perioperative chemotherapy is well-established for management of locoregional gastric cancer (LRGC). The American Joint Committee on Cancer advocates histopathologic assessment of tumor regression grade (TRG) but does not endorse a specific schema. We sought to examine the prognostic value of the recently revised National Comprehensive Cancer Network (NCCN) definition of TRG specifying TRG0 as no disease in primary tumor or lymph nodes.

PATIENTS AND METHODS

Patients with clinical-stage T2+/N+/M0 LRGC receiving preoperative chemotherapy and curative-intent gastrectomy were identified (2000-2020). TRG using the current NCCN definition was retrospectively assigned. Factors associated with TRG were examined using ordinal logistic regression and overall survival (OS) was assessed using the Kaplan-Meier method and Cox regression.

RESULTS

Among 117 patients, the most common chemotherapy regimen was epirubicin, cisplatin, plus fluorouracil or capecitabine (ECF/ECX) (n = 48, 41%), followed by folinic acid, fluorouracil, and oxaliplatin (FOLFOX) (n = 30, 26%), and fluorouracil, leucovorin, oxaliplatin, plus docetaxel (FLOT) (n = 13, 11%). TRG3 was the most common histopathologic response (n = 68, 58%), followed by TRG2 (n = 25, 21%), TRG1 (n = 18, 15%), and, lastly, TRG0 (n = 6, 5.1%). The only preoperative factor independently associated with lower TRG was gastroesophageal junction tumor location (OR 0.24, p = 0.012). Higher TRG was independently associated with worse OS in a stepwise fashion (HR 1.49, p = 0.026). Posttreatment pathologic lymph node status was the strongest prognostic factor (HR 1.93, p = 0.026). Independent prognostic value of TRG and ypT stage could not be shown due to substantial overlap.

CONCLUSIONS

TRG using the contemporary NCCN definition is associated with OS in LRGC. TRG0 is uncommon but with excellent prognosis. ypN status is the strongest prognostic factor and the revised NCCN definition acknowledging this is appropriate.

Safe performance of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in patients with HIV infection

Background

Patients with HIV (PHIV) are living longer with the adoption of anti‐retroviral therapy. As such, more patients are presenting with advanced cancer diagnoses, including peritoneal surface malignancies. The objective of this study was to assess the safety of CRS/HIPEC in this cohort of patients.

Case

Five PHIV were identified, four of whom underwent CRS/HIPEC. Primary sites of disease were low‐grade appendiceal mucinous tumors in three patients and peritoneal mesothelioma in the other. Operative time ranged from 7 to 14 h. One patient developed a Clavien grade II complication postoperatively. There was no instance of neutropenia identified. One patient died of disease 19 months after surgery; the remaining three patients are alive 11, 21, and 33 months postoperatively.

Conclusion

This study demonstrates that CRS/HIPEC can be performed in PHIV without prohibitive complications and operative recovery approximates that of non‐HIV patients. Though more study is needed, HIV should not preclude a patient from being offered CRS/HIPEC.

Management of Malignant Small Bowel Obstruction: Is Intestinal Bypass Effective Palliation?

BACKGROUND/PURPOSE

Malignant small bowel obstruction (mSBO) is a common consequence of advanced malignancies. Surgical consultation is common, however data on the outcomes following an operation are lacking. We investigated a specific operative approach-intestinal bypass-to determine the outcomes associated with this intervention.

METHODS

Patients with a preoperative diagnosis of mSBO who underwent intestinal bypass between 2015 and 2021 were included. Isolated colonic obstruction was excluded as was gastric outlet obstruction. Perioperative and postoperative outcomes were measured, including complications, overall survival, return to oral intake, and return to intended oncologic therapy. Patients were additionally grouped as to whether the operation was performed as elective or as inpatient.

RESULTS

Overall, 55 patients were identified, with a mean age of 61.2 ± 14 years. The most common primary malignancy was colorectal cancer (65.5%) and 80% of patients had a preoperative diagnosis of metastatic disease. Small bowel to colon was the most common bypass procedure (51%). Severe complications occurred in 25.5% of patients with three in-hospital mortalities (5.5%). Survival rates at 30, 90, and 180 days were 91%, 80%, and 62%, respectively. The majority of patients were discharged to home (85.5%) and were tolerating an oral diet (74.6%). Twenty-seven patients (49.1%) returned to some form of oncologic treatment.

CONCLUSIONS

Patients with mSBO face a potentially terminal condition. In this study, approximately 75% of patients who underwent intestinal bypass were able to regain the ability to eat, and 49% returned to oncologic therapy. Although retrospective, these data suggest the approach is efficacious for palliation of this difficult sequela of advanced cancer.

Development and Validation of an Explainable Machine Learning Model for Major Complications After Cytoreductive Surgery

Importance

Cytoreductive surgery (CRS) is one of the most complex operations in surgical oncology with significant morbidity, and improved risk prediction tools are critically needed. Machine learning models can potentially overcome the limitations of traditional multiple logistic regression (MLR) models and provide accurate risk estimates.

Objective

To develop and validate an explainable machine learning model for predicting major postoperative complications in patients undergoing CRS.

Design, Setting, and Participants

This prognostic study used patient data from tertiary care hospitals with expertise in CRS included in the US Hyperthermic Intraperitoneal Chemotherapy Collaborative Database between 1998 and 2018. Information from 147 variables was extracted to predict the risk of a major complication. An ensemble-based machine learning (gradient-boosting) model was optimized on 80% of the sample with subsequent validation on a 20% holdout data set. The machine learning model was compared with traditional MLR models. The artificial intelligence SHAP (Shapley additive explanations) method was used for interpretation of patient- and cohort-level risk estimates and interactions to define novel surgical risk phenotypes. Data were analyzed between November 2019 and August 2021.

Exposures

Cytoreductive surgery.

Main Outcomes and Measures

Area under the receiver operating characteristics (AUROC); area under the precision recall curve (AUPRC).

Results

Data from a total 2372 patients were included in model development (mean age, 55 years [range, 11-95 years]; 1366 [57.6%] women). The optimized machine learning model achieved high discrimination (AUROC: mean cross-validation, 0.75 [range, 0.73-0.81]; test, 0.74) and precision (AUPRC: mean cross-validation, 0.50 [range, 0.46-0.58]; test, 0.42). Compared with the optimized machine learning model, the published MLR model performed worse (test AUROC and AUPRC: 0.54 and 0.18, respectively). Higher volume of estimated blood loss, having pelvic peritonectomy, and longer operative time were the top 3 contributors to the high likelihood of major complications. SHAP dependence plots demonstrated insightful nonlinear interactive associations between predictors and major complications. For instance, high estimated blood loss (ie, above 500 mL) was only detrimental when operative time exceeded 9 hours. Unsupervised clustering of patients based on similarity of sources of risk allowed identification of 6 distinct surgical risk phenotypes.

Conclusions and Relevance

In this prognostic study using data from patients undergoing CRS, an optimized machine learning model demonstrated a superior ability to predict individual- and cohort-level risk of major complications vs traditional methods. Using the SHAP method, 6 distinct surgical phenotypes were identified based on sources of risk of major complications.

Evaluation of Tumor DNA Sequencing Results in Patients with Gastric and Gastroesophageal Junction Adenocarcinoma Stratified by TP53 Mutation Status

Background

Gastric cancer (GC) and gastroesophageal junction adenocarcinomas (GEJ) are molecularly diverse. TP53 is the most frequently altered gene with approximately 50% of patients harboring mutations. This qualitative study describes the distinct genomic alterations in GCs and GEJs stratified by TP53 mutation status.

Patients and Methods

Tumor DNA sequencing results of 324 genes from 3741 patients with GC and GEJ were obtained from Foundation Medicine. Association between gene mutation frequency and TP53 mutation status was examined using Fisher’s exact test. Functional gene groupings representing molecular pathways suggested to be differentially mutated in TP53 wild-type (TP53WT) and TP53 mutant (TP53MUT) tumors were identified. The association of the frequency of tumors containing a gene mutation in the molecular pathways of interest and TP53 mutation status was assessed using Fisher’s exact test with a P-value of &lt;.01 deemed statistically significant for all analyses.

Results

TP53 mutations were noted in 61.6% of 2946 GCs and 81.4% of 795 GEJs (P &lt; .001). Forty-nine genes had statistically different mutation frequencies in TP53WT vs. TP53MUT patients. TP53WT tumors more likely had mutations related to DNA mismatch repair, homologous recombination repair, DNA and histone methylation, Wnt/B-catenin, PI3K/Akt/mTOR, and chromatin remodeling complexes. TP53MUT tumors more likely had mutations related to fibroblast growth factor, epidermal growth factor receptor, other receptor tyrosine kinases, and cyclin and cyclin-dependent kinases.

Conclusion

The mutational profiles of GCs and GEJs varied according to TP53 mutation status. These mutational differences can be used when designing future studies assessing the predictive ability of TP53 mutation status when targeting differentially affected molecular pathways.

Tumor regression grade and overall survival following gastrectomy with neoadjuvant therapy for gastric cancer

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Background: Perioperative chemotherapy is the standard of care for locoregional gastric cancers in western populations. However, the impact of response to therapy as a biomarker of cancer survival has not been fully defined. This study focuses on the pathological response to neoadjuvant chemotherapy, as measured by tumor regression grade (TRG), for gastric cancer and its impact on patient outcomes, primarily overall survival. Methods: Patients undergoing gastrectomy for nonmetastatic invasive gastric adenocarcinoma following perioperative chemotherapy (clinical T2+/N+cM0) were identified from an institutional database (2000-2021). Demographics, clinical staging including histologic grade, surgical factors and survival outcomes were included. The association between TRG and overall survival from time of surgery was assessed. OS was estimated using the Kaplan Meier method with adjustment for covariates using Cox regression. Results: One hundred seventeen patients were identified. Median age was 65 years (IQR 57–73). The majority of the patients were male (n = 64, 55%). Seventy-six patients underwent total gastrectomy, 22 subtotal gastrectomy, and 19 distal gastrectomy. Six patients (5.1%) had a TRG of 0, 18 patients (15.4%) had a TRG of 1, 25 patients (21.4%) had a TRG of 2, and 68 patients (58.1%) had a TRG of 3. Median survival overall was 40.9 months (95% CI 28.7–66.4). TRG status was not significantly different between chemotherapy regimens (doublet vs triplet, p = 0.96). Median survival was longest in the TRG 0 group (86.9 months), followed sequentially by TRG 1 (74.5 months), TRG 2 (51.5 months), and lastly, TRG 3 group with 27.0 months. Increased tumor regression (lower TRG) was significantly associated with prolonged survival (p < 0.01 by log-rank for trend). After adjustment for clinical patient factors and tumor factors, TRG remained significantly associated with overall survival (Table; TRG hazard ratio 1.62, p = 0.007). In addition to TRG status, clinical T4 tumors and diffuse histology were associated with poor survival (cT4 hazard ratio 2.09, p = 0.039, diffuse histology hazard ratio 1.82 (p = 0.071). Conclusions: In patients receiving perioperative chemotherapy for treatment of gastric cancer, response to therapy as defined by TRG is independently prognostic of survival.[Table: see text]

Chemotherapy Versus Chemotherapy Plus Chemoradiation as Neoadjuvant Therapy for Resectable Gastric Adenocarcinoma: A Multi-institutional Analysis

OBJECTIVE

We compare neoadjuvant chemotherapy (CT) to neoadjuvant chemotherapy plus chemoradiation (CRT) for patients with gastric adenocarcinoma (GA).

SUMMARY OF BACKGROUND DATA

The optimal neoadjuvant therapy regimen for resectable GA is not defined.

METHODS

Utilizing data from 2 high-volume cancer centers, we analyzed patients who underwent surgery for localized GA from 1/1/2000-12/31/2017. Standard CT regimens were used according to treatment period. We compared propensity matched cohorts based on age, sex, race, histology, and clinical stage.

RESULTS

Four-hundred five patients (age 62 ± 12 year, 58% male, 56% White) were analyzed. 231 (57%) received CRT and 174 (43%) received CT. Groups differed based on histopathologic characteristics including preoperative stage (p = 0.013). To control for these differences, propensity matched cohorts of 113 CT and 113 CRT patients were compared. CRT had similar frequencies of microscopically negative resections to CT (93% vs 91%, p = 0.81), but higher rates of complete pathologic response (15% vs 4%, p = 0.003) and lower pathologic stage (p = 0.002). Completion of intended perioperative therapy occurred in 63% of CT and 91% of CRT patients (p < 0.001). Median DFS was 45mo (95%CI: 20-70) in the CT group and 113mo (95%CI: 75-151) in the CRT group (p = 0.018). Median OS was 53mo (95%CI: 30-77) versus 120mo (95%CI: 101-138); p = 0.015.

CONCLUSIONS

In this multi-institutional comparison of neoadjuvant CT and CRT for resectable GA, CRT is associated with higher rates of completed perioperative therapy, higher rates of complete pathologic response, lower pathologic stage, and improved survival.Level of Evidence: Level III.

The impact of socioeconomic status on survival in stage III colon cancer patients: A retrospective cohort study using the SEER census-tract dataset

Background

The impact of socioeconomic status (SES) has been described for screening and accessing treatment for colon cancer. However, little is known about the “downstream” effect in patients who receive guideline‐concordant treatment. This study assessed the impact of SES on cancer‐specific survival (CSS) and overall survival (OS) for stage III colon cancer patients.

Methods

The SEER Census Tract‐Level SES Dataset from 2004 to 2015 was used to identify stage III colon adenocarcinoma patients who received curative‐intent surgery and adjuvant chemotherapy. The predictor variable was census tract SES. SES was analyzed as quintiles. The outcome variables were OR and CSS. Statistical analysis included chi square tests for association, Kaplan–Meier, Cox, Fine and Gray regression for survival analysis.

Results

In total, 27,222 patients met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid/uninsured, higher T stage, and lower grade tumors. CSS at the 25th percentile was 54 months for the lowest SES quintile and 80 for the highest. Median OS was 113 months for the lowest SES quintile and not reached for highest. The 5‐year CSS rate was 72.4% for the lowest SES quintile compared to 78.9% in the highest (p < 0.001). The 5‐year OS rate was 66.5% for the lowest SES quintile and 74.6% in the highest (p < 0.001).

Conclusion

This is the first study to evaluate CSS and OS in an incidence‐based cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline‐based treatment, SES was associated with disparities in CSS and OS.

The Landmark Series: Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC) for Treatment of Gastric Cancer Metastatic to Peritoneum

Gastric cancer (GC) is a common cancer worldwide, with patients developing isolated peritoneal metastases (PM) in approximately 30% of cases. In patients with PM, prognosis is quite poor, and long-term survival is almost zero. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been demonstrated to be an effective treatment in many peritoneal malignancies, including appendiceal and ovarian cancers and in peritoneal mesothelioma. In this educational review, we summarize many of the seminal studies addressing the potential benefit of CRS/HIPEC for patients with gastric cancer and peritoneal metastases (GC/PM).

Impact of Perioperative Blood Transfusions on Outcomes After Hyperthermic Intraperitoneal Chemotherapy: A Propensity-Matched Analysis

BACKGROUND

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a major operation frequently necessitating red blood cell transfusion. Using multi-institutional data from the U.S. HIPEC Collaborative, this study sought to determine the association of perioperative allogenic blood transfusion (PABT) with perioperative outcomes after CRS/HIPEC.

METHODS

This retrospective cohort study analyzed patients who underwent CRS/HIPEC for peritoneal surface malignancy between 2000 and 2017. Propensity score-matching was performed to mitigate bias. Univariate analysis was used to compare demographic, preoperative, intraoperative, and postoperative variables. Factors independently associated with PABT were identified using multivariate analysis.

RESULTS

The inclusion criteria were met by 1717 patients, 510 (29.7%) of whom required PABT. The mean Peritoneal Cancer Index (PCI) of our cohort was 14.8 ± 9.3. Propensity score-matching showed an independent association between PABT and postoperative risk of pleural effusion, hemorrhage, pulmonary embolism, enteric fistula formation, Clavien-Dindo grades 3 and 4 morbidity, longer hospital stay, and reoperation (all P < 0.05 in the multivariate analysis). Compared with the patients who received 1 to 5 red blood cell (RBC) units, the patients who received more than 5 units had a greater risk of renal impairment, a longer intensive care unit (ICU) stay, and more postoperative infections. Finally, PABT was an independent predictor of worse survival for patients with appendiceal and colorectal primaries.

CONCLUSION

Even low levels of PABT for patients undergoing CRS/HIPEC are independently associated with a greater risk of infectious and non-infectious postoperative complications, and this risk is increased for patients receiving more than 5 RBC units. Worse survival was independently predicted by PABT for patients with peritoneal carcinomatosis of an appendiceal or colorectal origin.

The effect of gender on outcomes in esophageal cancer

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Background: Few epidemiological studies address differences in outcomes by gender in locoregional esophageal cancer (LEC) for which the current standard of care is chemoradiation followed by surgical resection. Although male gender is associated with the majority of LEC cases, we sought to determine if gender could impact clinical presentation as well as surgical and oncologic outcomes in our single institution 20 year experience. Methods: A retrospective query of our institution’s IRB-approved database of patients that had surgical therapy between 2008 and 2019 for esophageal cancer (EC) was performed. Patients were stratified by gender and analyzed based on characteristics such as tumor histology, tumor location, clinical stage at presentation, age at diagnosis, receipt of neoadjuvant therapy, surgical intent, surgical complications, length of post-operative hospital stay, response to neoadjuvant therapy, final pathology, and recurrence. Chi-square, ANOVA and Kaplan Meier survival analysis were performed on the previously defined groups. Results: The cohort studied included 1180 patients with resection for EC. Of those, 1005 (85.2%) had adenocarcinoma, 145 (12.3%) had squamous cell cancer (SCC), 10 (0.8%) had adenosquamous carcinoma, and 20 (1.7%) had other histological variants. There were 985 (83.5%) male patients and 195 (16.5%) female patients. SCC was more common in females (29.2% in females vs. 8.9% in males, p = 0.000) and females tended to have tumor location in the upper thoracic esophagus more often (4.7% in females vs. 0.9% of males, p = 0.000). Additionally, females developed surgical complications more often than males (72.2% vs. 64.7%, p = 0.045). Staging at diagnosis (p = 0.508), receipt of neoadjuvant treatment (p = 0.676), and age at diagnosis (65.3 years in males vs. 66.3 years in females, p = 0.934) had no association with gender. Response to neoadjuvant therapy (p = 0.157) and cancer recurrence (p = 0.434) did not have significant associations with gender. The median overall survival was not statistically significantly different but trended to be longer for females (73.4 months in females [95% CI: 51.5-95.4] vs. 47.0 months in males [95% CI: 39.6-54.5], p = 0.160). Conclusions: Based on our high-volume cancer center study, female patients were more likely to have SCC, upper thoracic esophageal lesions, and surgical complications following resection. While univariate analysis did not demonstrate significant differences in overall survival between genders, there are plans to report additional data after controlling for other variables. Further studies are warranted to validate these findings, given the potential for higher prioritization of an organ preservation approach for this patient population.

Comprehensive evaluation of genomic alterations in patients with gastric and gastroesophageal adenocarcinoma stratified according to TP53 mutation status

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Background: Gastric (GC) and gastroesophageal adenocarcinomas (GEA) are molecularly diverse. Molecular biomarkers of clinical significance have been identified that impact treatment decision making. TP53 is the most frequently altered gene with approximately 50% of patients harboring mutations. However, TP53 mutations have not yet been confirmed as a target of therapeutic benefit. This study aimed to identify distinct genomic alterations that are dominant in TP53 mutated (MUT) versus wild-type (WT) GC and GEA in order to elucidate alternative therapeutic targets within these subsets. Methods: De-identified data for 3741 patients with GC and GEA was obtained from Foundation Medicine. The data obtained were age, gender, tumor mutational burden (TMB), and the distinct genomic alterations noted on DNA sequencing. The dataset was sorted by TP53 mutation status. Differences in mutation frequency were detected using the Fisher’s exact test of independence with a p-value of < 0.01 designated as the cutoff value for statistical significance. Results: The dataset consisted of 2946 GCs and 795 GEAs. TP53 mutations were present in 65.8% of specimens. 61.6% of GCs and 81.4% of GEAs were TP53 MUT positive (p = < .001). Median TMB score and the frequency of tumors with a TMB score > 10 was similar in both TP53 MUT and WT groups. 49 genes had statistically different mutation frequencies in TP53 MUT vs. WT patients. Top co-occurring genetic alterations in TP53 MUT patients included amplification and point mutations in MYC, CCNE1, MET, ERBB2, and EGFR. Amplification and point mutations in MDM2, CDK4, ARID1A, PIK3CA, and ERBB3 were the top co-occurring genetic alterations in TP53 WT patients. Conclusions: There was a high frequency of TP53 mutations in this group of GC and GEA patients, with a higher incidence of TP53 mutations identified in GEA samples. The mutational profiles of these tumors differed according to TP53 mutation status. These differences may be able to serve as the foundation for future clinical investigations.

CRS/HIPEC with Major Organ Resection in Peritoneal Mesothelioma Does not Impact Major Complications or Overall Survival: A Retrospective Cohort Study of the US HIPEC Collaborative

INTRODUCTION

CRS/HIPEC is thought to confer a survival advantage for patients with malignant peritoneal mesothelioma (MPM). However, the impact of nonperitoneal organ resection is not clearly defined. We evaluated the impact of major organ resection (MOR) on postoperative outcomes and overall survival (OS).

PATIENTS AND METHODS

The US HIPEC collaborative database (2000-2017) was reviewed for MPM patients who underwent CRS/HIPEC. MOR was defined as total or partial resection of diaphragm, stomach, spleen, pancreas, small bowel, colon, rectum, kidney, ureter, bladder, and/or uterus. MOR was categorized as 0, 1, or 2+ organs.

RESULTS

A total of 174 patients were identified. Median PCI was 16 (3-39). The distribution of patients with MOR-0, MOR-1, and MOR-2+ was 94, 45, and 35 patients, respectively. MOR-1 and MOR-2+ groups had a higher frequency of any complication compared with MOR-0 (57.8%, 74.3%, and 48.9%, respectively, p = 0.035), but Clavien 3/4 complications were similar. Median length of stay was slightly higher in the MOR-1 and MOR-2+ groups (10 and 11 days) compared with the MOR-0 cohort (9 days, p = 0.005). Incomplete cytoreduction, ASA class 4, and male gender were associated with increased mortality on unadjusted analysis; however, their impact on OS was attenuated on multivariable analysis. MOR was not associated with OS based on these data (MOR-1: HR 1.67, 95% CI 0.59-4.74; MOR-2+ : HR 0.77, 95% CI 0.22-2.69).

CONCLUSIONS

MOR was not associated with an increase in major complications or worse OS in patients undergoing CRS/HIPEC for MPM and should be considered, if necessary, to achieve complete cytoreduction for MPM patients.

The Impact of Histologic Subtype on Receipt of Adjuvant Chemotherapy and Overall Survival in Stage III Colon Cancer: a Retrospective Cohort Analysis

BACKGROUND

The impact of adjuvant chemotherapy (AT) on resected colon adenocarcinoma based on histologic subtype is poorly defined and extrapolated from patients with advanced disease. We evaluated the receipt and effect of AT on overall survival stratified by histologic subtype-mucinous, non-mucinous, and signet ring adenocarcinomas.

METHODS

A retrospective cohort study from 2004 to 2015 was conducted using the National Cancer Database. Patients with colon adenocarcinoma who underwent curative resection with pathologic stage III were included. Appendiceal and rectal tumors were excluded. The predictor variable was histologic subtype, and outcome variables were overall survival and receipt of AT.

RESULTS

Absolute survival was increased for mucinous, non-mucinous, and signet ring tumors with receipt of AT (88.1, 108.9, and 38.1 months, respectively). In multivariable analysis, there was no difference in overall survival for mucinous patients relative to non-mucinous patients. In subgroup analysis, a modest survival advantage for non-mucinous patients relative to the mucinous patients was observed (HR, 0.92; 95% CI, 0.89-0.95). In multivariable modeling, non-mucinous and signet ring adenocarcinoma had decreased odds of receipt of AT relative to mucinous adenocarcinoma patients.

CONCLUSIONS

Histologic subtype is an important prognostic factor for overall survival for stage III colon adenocarcinoma. Although the magnitude of the benefit of AT may vary in stage III curatively resected patients, it has a substantial survival benefit across all histologic subtypes. Based on these observations, there is no indication that patients with stage III mucinous adenocarcinoma of the colon should not receive AT. All patients with resected stage III colon cancer should be referred for AT regardless of histologic subtype.

Implications of Postoperative Complications for Survival After Cytoreductive Surgery and HIPEC: A Multi-Institutional Analysis of the US HIPEC Collaborative

BACKGROUND

Postoperative complications (POCs) are associated with worse oncologic outcomes in various cancer histologies. The impact of POCs on the survival of patients with appendiceal or colorectal cancer after cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is unknown.

METHODS

The US HIPEC Collaborative (2000-2017) was reviewed for patients who underwent CCR0/1 CRS/HIPEC for appendiceal/colorectal cancer. The analysis was stratified by noninvasive appendiceal neoplasm versus invasive appendiceal/colorectal adenocarcinoma. The POCs were grouped into infectious, cardiopulmonary, thromboembolic, and intestinal dysmotility. The primary outcomes were overall survival (OS) and recurrence-free survival (RFS).

RESULTS

Of the 1304 patients, 33% had noninvasive appendiceal neoplasm (n = 426), and 67% had invasive appendiceal/colorectal adenocarcinoma (n = 878). In the noninvasive appendiceal cohort, POCs were identified in 55% of the patients (n = 233). The 3-year OS and RFS did not differ between the patients who experienced a complication and those who did not (OS, 94% vs 94%, p = 0.26; RFS, 68% vs 60%, p = 0.15). In the invasive appendiceal/colorectal adenocarcinoma cohort, however, POCs (63%; n = 555) were associated with decreased 3-year OS (59% vs 74%; p < 0.001) and RFS (32% vs 42%; p < 0.001). Infectious POCs were the most common (35%; n = 196). In Multivariable analysis accounting for gender, peritoneal cancer index (PCI), and incomplete resection (CCR1), infectious POCs in particular were associated with decreased OS compared with no complication (hazard ratio [HR] 2.08; p < 0.01) or other types of complications (HR, 1.6; p < 0.01). Similarly, infectious POCs were independently associated with worse RFS (HR 1.61; p < 0.01).

CONCLUSION

Postoperative complications are associated with decreased OS and RFS after CRS/HIPEC for invasive histology, but not for an indolent disease such as noninvasive appendiceal neoplasm, and this association is largely driven by infectious complications. The exact mechanism is unknown, but may be immunologic. Efforts must target best practices and standardized prevention strategies to minimize infectious postoperative complications.

Repeat Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Is Not Associated with Prohibitive Complications: Results of a Multiinstitutional Retrospective Study

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) is offered to select patients with peritoneal metastases. In instances of recurrence/progression, a repeat CRS/HIPEC may be considered. The perioperative morbidity and the potential oncologic benefits are not well described.

PATIENTS AND METHODS

We performed a retrospective analysis of a multiinstitutional database to assess the perioperative outcomes following repeat CRS/HIPEC (repeat). Kaplan-Meier and Cox estimates were used to assess survival.

RESULTS

In the entire cohort, 2157 patients were analyzed, with 158 (7.3%) in the repeat cohort. The rate of complete cytoreduction was 89.8% versus 83.0% in initial versus repeat groups. The overall incidence of major complications was similar (26.3% vs. 30.7%); however, reoperation was more common in the repeat group. Perioperative outcomes such as length of stay and nonhome discharge were not significantly different. For the entire cohort, 5-year overall survival (OS) was 56.0% in the initial group and 59.5% in the repeat group. In patients with only appendiceal cancer, we observed a 5-year OS of 64.0% in the initial group compared with 67.3% in the repeat cohort. For patients with appendiceal cancer who developed a recurrence/progression, median OS was 36 months in the no repeat operation group compared with 73 months for those that did. Multivariable regression demonstrated that completeness of cytoreduction and tumor grade were associated with OS, but repeat operation was not.

CONCLUSIONS

Repeat CRS/HIPEC is not associated with prohibitive risk. Survival is possibly improved, and therefore, repeat operation should be considered in selected patients with recurrent or progressive disease.

Outcomes of Gastric Resection in the Establishment of a Comprehensive Oncologic Robotic Program

BACKGROUND

Robotic-assisted gastrectomy is increasingly utilized for the treatment of gastric malignancies. However, the benefits of robotic surgery have been questioned. This study describes short-term outcomes in the establishment of a comprehensive robotic program for gastric malignancies.

MATERIALS AND METHODS

Patients who underwent robotic-assisted gastric resections between 2013 and 2018 were studied. Preoperative measures and surgical outcomes were analyzed. Finally we studied and analyzed robotic and open gastrectomy for the management of gastric adenocarcinoma (GC) at the same institution between 2000 and 2018 for quality benchmarking.

RESULTS

Forty six patients (pts.) underwent robotic-assisted gastric resections. 26 (56.5%) were male, with a median age of 62 y (range: 29-87). Pathology included GC, gastrointestinal stromal tumors, neuroendocrine tumors, metastatic lesions, and benign processes. 19 pts. underwent total gastrectomy, 16 distal gastrectomy, four subtotal gastrectomy, and seven wedge resection. Pts. undergoing distal gastrectomy and wedge resection experienced shorter operative times and length of stay than total gastrectomy (P < 0.01; P < 0.01). Four operations (8.8%) were converted to open and 13 pts (28.3%) had postoperative complications, including an 8.7% readmission rate. Median lymph nodes retrieved during total, subtotal, and distal gastrectomy were 20 (13-46), 12.5 (0-26), and 16.5 (0-34), respectively. All pts. underwent margin negative resection. Median follow-up for GC was 21 mo, and 60% of pts. received adjuvant therapy at a median of 59d (range: 23-106).

CONCLUSIONS

Robotic gastrectomy is a feasible alternative to open gastrectomy. Our results will help establish benchmarks to improve perioperative outcomes, especially length of stay and time to initiation of therapy.

What is the Optimal Preoperative Imaging Modality for Assessing Peritoneal Cancer Index? An Analysis From the United States HIPEC Collaborative

BACKGROUND

Radiographic prediction of peritoneal carcinomatosis index (PCI) can improve patient selection for cytoreductive surgery. We aimed to determine the correlation of computed tomography (CT)-predicted PCI (CT-PCI) and magnetic resonance imaging (MRI)-predicted PCI (MRI-PCI) with intraoperative-PCI, and if a preoperative-PCI cutoff is associated with incomplete cytoreduction.

PATIENTS AND METHODS

Patients from the US HIPEC Collaborative (2000-2017) with appendiceal, colorectal, or peritoneal mesothelioma (PM) histology who underwent cytoreductive surgery were included. Pearson correlation coefficients were used to determine correlation between preoperative and intraoperative-PCI values. Fisher r-to-z transformation was used to compare correlations.

RESULTS

A total of 488 patients were included. Of these, 34% had noninvasive appendiceal, 30% invasive appendiceal, 28% colorectal, and 8% PM histology. CT-PCI was correlated with intraoperative-PCI for patients with noninvasive and invasive appendiceal and colorectal histologies (r = 0.689, 0.554, and 0.571; all P < .001), but not PM (r = 0.188; P = .295). MRI-PCI was correlated with intraoperative-PCI for all histologies (non-invasive appendiceal: r = 0.591; P = .002; invasive appendiceal: r = 0.848; P < .001; colorectal: r = 0.729; P < .001; PM: r = 0.890; P = .007). Comparing CT and MRI, correlations were similar in noninvasive appendiceal and colorectal histologies; MRI was better for invasive appendiceal and PM (P = .005 and P = .021, respectively). Twenty-eight (6%) patients underwent an incomplete cytoreduction (cytoreduction score, 2-3). PCI greater than 15 was associated with cytoreduction score of 2 to 3 for both CT and MRI (CT-PCI: odds ratio, 3.0; P = .033; MRI-PCI: odds ratio, 7.6; P = .071).

CONCLUSIONS

In this multi-institutional cohort, CT and MRI-PCI correlate well with intraoperative-PCI. MRI appears to be superior for invasive appendiceal and peritoneal mesothelioma. External validation in a larger population is needed.

Primary Tumor Sidedness is Predictive of Survival in Colon Cancer Patients Treated with Cytoreductive Surgery With or Without Hyperthermic Intraperitoneal Chemotherapy: A US HIPEC Collaborative Study

INTRODUCTION

The clinical relevance of primary tumor sidedness is not fully understood in colon cancer patients with peritoneal metastasis treated with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC).

METHODS

This was a retrospective cohort study of a multi-institutional database of patients with peritoneal surface malignancy at 12 participating high-volume academic centers from the US HIPEC Collaborative.

RESULTS

Overall, 336 patients with colon primary tumors who underwent curative-intent CRS with or without HIPEC were identified; 179 (53.3%) patients had right-sided primary tumors and 157 (46.7%) had left-sided primary tumors. Patients with right-sided tumors were more likely to be older, male, have higher Peritoneal Cancer Index (PCI), and have a perforated primary tumor, but were less likely to have extraperitoneal disease. Patients with complete cytoreduction (CC-0/1) had a median disease-free survival (DFS) of 11.5 months (95% confidence interval [CI] 7.6-15.3) versus 13.1 months (95% CI 9.5-16.8) [p = 0.158] and median overall survival (OS) of 30 months (95% CI 23.5-36.6) versus 45.4 months (95% CI 35.9-54.8) [p = 0.028] for right- and left-sided tumors; respectively. Multivariate analysis revealed that right-sided primary tumor was an independent predictor of worse DFS (hazard ratio [HR] 1.75, 95% CI 1.19-2.56; p =0.004) and OS (HR 1.72, 95% CI 1.09-2.73; p = 0.020).

CONCLUSION

Right-sided primary tumor was an independent predictor of worse DFS and OS. Relevant clinicopathologic criteria, such as tumor sidedness and PCI, should be considered in patient selection for CRS with or without HIPEC, and guide stratification for clinical trials.

A Survey of the Complex General Surgical Oncology Fellowship Programs Regarding Applicant Selection and Rank

BACKGROUND

There is significant demand for training in Complex General Surgical Oncology (CGSO) fellowships. Previous work has explored objective quantitative metrics of applicants that matriculated to CGSO fellowships; however, ambiguity remains concerning academic benchmarks and qualitative factors that impact matriculation.

STUDY DESIGN

A web-based survey was sent to each ACGME/SSO-approved CGSO fellowship training program. The survey was comprised of 24 questions in various forms, including dichotomous, ranked, and five-point Likert scale questions.

RESULTS

Twenty-nine of 30 program directors (97%) submitted complete survey responses, representing 64 of the 65 CGSO fellowship positions (99%) currently offered. Programs received a mean of 73 applications per cycle (range 50-125) and granted a mean of 26 interviews (range 2-45). Seventy-two percent of programs had an established benchmark for ABSITE score percentile before offering a candidate an interview, with 62% of those programs setting that benchmark above the 50^th percentile. The majority of programs also had established benchmarks for quantity of first author publications (mean: 2.3) and all publications of any authorship (mean: 4.4). An applicant's interview was ranked as the most important factor in determining inclusion on the program's rank list. The ability to work as part of a team, interpersonal interaction/communication abilities, and operative skills were rated as most important applicant characteristics, whereas an applicant's personal statement was ranked as least important.

CONCLUSIONS

After established academic benchmarks have been met, a multitude of factors influences ranking of applicants to the CGSO fellowship, most of which are assessed at the interview.

Thromboelastography demonstrates perioperative hypercoagulability in hepato-pancreato-biliary patients and supports routine administration of preoperative and early postoperative venous thromboembolism chemoprophylaxis

BACKGROUND

We hypothesized hepato-pancreato-biliary (HPB) surgery patients are more likely to be hypercoagulable than hypocoagulable, and that bleeding risks from VTE chemoprophylaxis are low. This study sought to use thromboelastography (TEG) to compare coagulation profiles with bleeding/thrombotic events in HPB patients receiving standardized perioperative chemoprophylaxis.

METHODS

Consecutive patients undergoing HPB resections by three surgeons at one institution (January 2014-December 2015) received preoperative and early postoperative VTE chemoprophylaxis and were evaluated with TEGs. Coagulation profiles were compared to bleeding/thrombotic events.

RESULTS

Of 87 total patients, 83 (95.4%) received preoperative chemoprophylaxis and 100% received it postoperatively. Median estimated blood loss was 190 ml. Only 2 (2.3%) patients received intraoperative transfusions. None required transfusions at 72-hours. Only 2 were transfused within 30 days. There was 1 (1.1%) 30-day VTE event. Of 83 preoperative TEGs, 29 (34.9%) were hypercoagulable and only 8 (9.6%) were hypocoagulable/fibrinolytic. Of 73 postoperative TEGs, 34 (46.6%) were hypercoagulable and just 8 (11.0%) were hypocoagulable/fibrinolytic. .

CONCLUSION

With routine perioperative chemoprophylaxis, both VTE and bleeding events were negligible. Perioperative TEG revealed a considerable proportion (46.6%) of HPB patients were hypercoagulable. HPB patients can receive standardized preoperative/early postoperative VTE chemoprophylaxis with effective results and minimal concern for perioperative hemorrhage.

Defining the optimal timing of adjuvant therapy for resected pancreatic adenocarcinoma: A statewide cancer registry analysis

BACKGROUND

Long-term results of the ESPAC-3 trial suggest that while completing adjuvant therapy (AT) is necessary after resection of pancreatic ductal adenocarcinoma (PDAC), early initiation (within 8 weeks) may not be associated with improved overall survival (OS). The primary aim of this study was to evaluate the OS impact of early versus late AT in a statewide analysis.

METHODS

Patients with stages I-III PDAC in the Kentucky Cancer Registry (KCR) from 2004 to 2013, were evaluated. Those undergoing pancreatectomy were stratified into two groups ("early," <8 weeks, vs. "late," 8-16 weeks).

RESULTS

Of 2,221 diagnosed patients with stages I-III, 831 (37.4%) underwent pancreatectomy upfront. Of these, only 420 (50.5%) received AT. Initiation date of AT was not associated with OS (median OS: early, 20.2 vs. late, 19.0 months, P = 0.97). On multivariate analysis, factors that affected OS included stage (II, HR-1.82, P = 0.017; III, HR-3.77, P < 0.001), node positivity (HR-1.51, P = 0.004), poorly/undifferentiated grade (HR-1.34; P = 0.011), but not AT initiation date.

CONCLUSIONS

In this statewide analysis, there was no difference in OS between early and late AT initiation for resected PDAC. The ideal window for AT initiation remains unknown as tumor biology continues to trump regimens from the past decade. J. Surg. Oncol. 2016;114:451-455. © 2016 Wiley Periodicals, Inc.

Analysis of Clinical and Molecular Factors Impacting Oncologic Outcomes in Undifferentiated Pleomorphic Sarcoma

BACKGROUND

Undifferentiated pleomorphic sarcomas (UPS) present a diagnostic and therapeutic challenge. Identification of prognostic molecular markers is required for the discovery of novel treatment approaches. The purpose of this study was to correlate clinicopathologic variables, expression of tyrosine kinase receptors, and markers of cell cycle progression and survival with oncologic outcomes.

METHODS

A tissue microarray containing 208 primary UPS samples was analyzed by immunohistochemistry for protein markers and in situ hybridization for microRNA. Staining results were correlated with clinicopathologic features and oncologic outcomes. Univariate and multivariate analyses were conducted to assess associations between expression of protein markers, mi-RNA, and outcome.

RESULTS

At a median follow-up of 3.9 years (9 years for survivors), 5-year disease-specific survival (DSS) was 63 %. Clinical variables associated with improved DSS included age <61 years, tumor size <10 cm, margin-negative resection, and sporadic-tumor status. At the protein level, loss of cyclin D1 (p = 0.06), pEGFR (p = 0.023), pIGF-1R (p = 0.022), and PTEN (p < 0.001) and overexpression of AXL (p = 0.015) were associated with reduced DSS on univariate analysis. Ki67, PCNA, and pEGFR were more highly expressed in sporadic UPS than radiation-associated (RA-UPS), whereas RA-UPS samples expressed higher levels of both phosphorylated and total IGF-1R.

DISCUSSION

Loss of cyclin D1, overexpression of AXL, and loss of PTEN are associated with poor cancer-specific outcomes and warrant further investigation in UPS. The differences in protein expression in sporadic versus RA-UPS may indicate that the activated molecular signaling nodes may be different for each specific histology and also could explain the aggressive phenotype seen in RA-UPS compared with the sporadic lesions.

Feeding tube placement during cytoreductive surgery and heated intraperitoneal chemotherapy does not improve postoperative nutrition and is associated with longer length of stay and higher readmission rates

BACKGROUND

Patients with colorectal cancer and peritoneal carcinomatosis (CRC/PC) may benefit from cytoreductive surgery and heated intraperitoneal chemotherapy (CRS/HIPEC). Nutritional support is frequently required for patients after CRS/HIPEC. It remains unclear if placement of feeding access is of benefit in regard to improving postoperative nutrition in this patient population.

MATERIALS AND METHODS

Patients with CRC/PC who underwent complete cytoreduction were evaluated. Preoperative and postoperative nutritional data and discharge outcomes were retrospectively recorded. The presence of a feeding tube and PCI scores were recorded by review of operative notes. Readmission rates were calculated for patients at 30 d and 60 d after discharge from hospital.

RESULTS

Forty-one patients underwent CRS/HIPEC, 25 had feeding tube placement at the time of surgery. Weight loss was common after HIPEC as 38 of 41 patients demonstrated weight loss. The mean weight loss was 7.6%. total parenteral nutrition was required at discharge in four patients (7.9%); three of these patients had feeding access placed. There was no difference in the degree of weight loss between groups (7.1 ± 3.7% no tube versus 7.9 ± 5.8% patients with tube; P = 0.608). The mean decrease in albumin was 12.7% but was not significantly different in patients with feeding access and those without (10.0% versus 14.75%; P = 0.773). Sixty-day readmission rates were higher in patients with feeding tubes (36% compared with 0%, P < 0.01).

CONCLUSIONS

Significant nutritional loss is common after CRS/HIPEC for patients with CRC/PC. Feeding tube placement does not prevent this and appears to be related to higher readmission rates and longer length of stay.

Warfarin Blocks Gas6-Mediated Axl Activation Required for Pancreatic Cancer Epithelial Plasticity and Metastasis

Repurposing "old" drugs can facilitate rapid clinical translation but necessitates novel mechanistic insight. Warfarin, a vitamin K "antagonist" used clinically for the prevention of thrombosis for more than 50 years, has been shown to have anticancer effects. We hypothesized that the molecular mechanism underlying its antitumor activity is unrelated to its effect on coagulation, but is due to inhibition of the Axl receptor tyrosine kinase on tumor cells. Activation of Axl by its ligand Gas6, a vitamin K-dependent protein, is inhibited at doses of warfarin that do not affect coagulation. Here, we show that inhibiting Gas6-dependent Axl activation with low-dose warfarin, or with other tumor-specific Axl-targeting agents, blocks the progression and spread of pancreatic cancer. Warfarin also inhibited Axl-dependent tumor cell migration, invasiveness, and proliferation while increasing apoptosis and sensitivity to chemotherapy. We conclude that Gas6-induced Axl signaling is a critical driver of pancreatic cancer progression and its inhibition with low-dose warfarin or other Axl-targeting agents may improve outcome in patients with Axl-expressing tumors.

Abstract B78: Warfarin blocks Gas6-mediated Axl activation required for pancreatic tumor plasticity and metastasis

Warfarin, a vitamin K antagonist anti-coagulant in clinical use for over 50 years, is reported to exert anti-cancer effects. We hypothesized that the molecular mechanism underlying the observed anti-tumor effects of warfarin is unrelated to generalized anti-coagulation, but rather due to inhibition of the Axl receptor tyrosine kinase. Activation of Axl by its ligand Gas6, a vitamin K-dependent protein, is inhibited at doses of warfarin that do not affect coagulation. Here we document that inhibiting Gas6-mediated Axl activation with low dose warfarin blocks pancreatic cancer progression and spread. Warfarin and other Axl-targeting agents inhibit tumor progression and block spontaneous metastasis in multiple murine models of pancreatic cancer. Warfarin inhibited Axl-dependent tumor cell migration, invasiveness and proliferation while increasing apoptosis and sensitivity to chemotherapy. We demonstrate that Axl signaling is necessary for pancreatic tumor cell epithelial plasticity which is potently reversed by warfarin or selective Axl inhibition in vitro and in vivo. We anticipate Axl is a critical driver of pancreatic cancer progression and its inhibition with low dose warfarin or Axl-selective targeting agents may significantly improve outcome in patients.

Citation Format: Amanda Kirane, Kathleen W. Ludwig, Gry Haaland, Tone Sandal, Renata Ranaweera, Jason E. Toombs, Laura A. Sullivan, Miao Wang, Noah Sorrelle, Sean P. Dineen, Michael T. Dellinger, James B. Lorens, Rolf A. Brekken. Warfarin blocks Gas6-mediated Axl activation required for pancreatic tumor plasticity and metastasis. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2015;75(13 Suppl):Abstract nr B78.

Feasibility of Subcutaneous Gentamicin and Pressurized Irrigation as Adjuvant Strategies to Reduce Surgical Site Infection in Colorectal Surgery: Results of a Pilot Study

Surgical site infections (SSIs) remain a common and costly morbidity after colorectal surgery. This rate remains high even in the setting of strict adherence to Surgical Care Improvement Project Protocols. The aim of our pilot study was to determine the feasibility and safety of subcutaneous gentamicin injection or pressurized irrigation as adjuncts to reduce SSI. A total of 132 patients who underwent colorectal surgery at the VA North Texas Health Care System were prospectively assigned to a pressurized irrigation group (n = 44), a preincision gentamicin injection group (n = 48), or control (n = 40). The primary objective was to assess safety and feasibility of these strategies. Patient demographics were matched among groups. Univariate and multivariate analyses were performed to identify possible predictions of SSI in this cohort. The rate of SSI in the control group was 25 per cent, 13.5 per cent in the pressurized irrigation group, and 12.5 per cent in the gentamicin group ( P = 0.26). Combined, the intervention groups had a 13 per cent SSI versus 25 per cent control ( P = 0.09). Operative time was not increased by the interventions and no intraoperative complications specifically related to the interventions were noted. Postoperative complications were not different between groups. Both albumin and body mass index were associated with SSI. Body mass index was and independent predictor of SSI ( P = 0.006). In conclusion, this pilot study demonstrates the feasibility of the interventions described. There was no detrimental effect of either intervention. There was trend toward a reduction in SSI in the intervention group, which warrants further investigation.

Feasibility of subcutaneous gentamicin and pressurized irrigation as adjuvant strategies to reduce surgical site infection in colorectal surgery: results of a pilot study

Surgical site infections (SSIs) remain a common and costly morbidity after colorectal surgery. This rate remains high even in the setting of strict adherence to Surgical Care Improvement Project Protocols. The aim of our pilot study was to determine the feasibility and safety of subcutaneous gentamicin injection or pressurized irrigation as adjuncts to reduce SSI. A total of 132 patients who underwent colorectal surgery at the VA North Texas Health Care System were prospectively assigned to a pressurized irrigation group (n = 44), a preincision gentamicin injection group (n = 48), or control (n = 40). The primary objective was to assess safety and feasibility of these strategies. Patient demographics were matched among groups. Univariate and multivariate analyses were performed to identify possible predictions of SSI in this cohort. The rate of SSI in the control group was 25 per cent, 13.5 per cent in the pressurized irrigation group, and 12.5 per cent in the gentamicin group (P = 0.26). Combined, the intervention groups had a 13 per cent SSI versus 25 per cent control (P = 0.09). Operative time was not increased by the interventions and no intraoperative complications specifically related to the interventions were noted. Postoperative complications were not different between groups. Both albumin and body mass index were associated with SSI. Body mass index was and independent predictor of SSI (P = 0.006). In conclusion, this pilot study demonstrates the feasibility of the interventions described. There was no detrimental effect of either intervention. There was trend toward a reduction in SSI in the intervention group, which warrants further investigation.

Radiation-Associated Undifferentiated Pleomorphic Sarcoma is Associated with Worse Clinical Outcomes than Sporadic Lesions

BACKGROUND

Radiation therapy is used increasingly as a component of multidisciplinary treatment for many solid tumors. One complication of such treatment is the development of radiation-associated sarcoma (RAS). Undifferentiated pleomorphic sarcoma (UPS), previously termed "malignant fibrous histiocytoma" (MFH) is the most common histologic subtype of RAS. This study investigated the clinical outcomes for patients with radiation-associated UPS (RA-UPS/MFH).

METHODS

The study identified 1068 patients with UPS/MFH treated at the authors' institution. Patient and tumor factors were collected and compared. Regression analysis was performed to identify independent predictors of survival. A matched-cohort survival and recurrence analysis was performed for radiation-associated and sporadic UPS/MFH.

RESULTS

The findings showed that RA-UPS/MFH comprised 5.1 % of the UPS population. The median latency to the development of RA-UPS/MFH was 9.3 years. The 5-year disease-specific survival (DSS) was 52.2 % for patients identified with RA-UPS/MFH (n = 55) compared with 76.4 % for patients with unmatched sporadic UPS/MFH (n = 1,013; p < 0.001). A matched-cohort analysis also demonstrated that the 5-year DSS was significantly worse for RA-UPS/MFH (52.2 vs 73.4 %; p = 0.002). Furthermore, higher local recurrence rates were observed for patients with RA-UPS/MFH than for patients with sporadic lesions (54.5 vs 23.5 %; p < 0.001). Radiation-associated status and incomplete resection were identified as independent predictors of local recurrence.

CONCLUSION

This study demonstrated worse clinical outcomes for patients with RA-UPS/MFH than for patients with sporadic UPS/MFH. Local recurrence was significantly higher for patients with RA-UPS/MFH, suggesting a unique tumor biology for this challenging disease.

A Simplified Preoperative Assessment Predicts Complete Cytoreduction and Outcomes in Patients with Low-Grade Mucinous Adenocarcinoma of the Appendix

BACKGROUND

Complete cytoreduction with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been shown to improve survival in patients with low-grade mucinous adenocarcinoma (LGMA). However, incomplete cytoreduction exposes patients to significant morbidity without a similar survival benefit. Preoperative assessment of the ability to achieve CRS is therefore a critical step in selecting patients for CRS/HIPEC.

OBJECTIVE

The aim of this study was to develop and validate a preoperative scoring system to accurately predict the ability to achieve complete cytoreduction in patients with LGMA of the appendix.

METHODS

A simplified preoperative assessment for appendix tumor (SPAAT) score was developed based on computed tomography scan findings thought to predict incomplete cytoreduction. We applied the SPAAT score to patients with LGMA to determine the ability of the score to predict complete cytoreduction. This scoring system was then applied to a separate cohort of patients from a different institution. Sensitivity and specificity were determined for the SPAAT score. Survival was calculated and correlated with the SPAAT score and the completeness of cytoreduction score.

RESULTS

A SPAAT score of <3 is a significant predictor of complete cytoreduction in the derivation cohort. In the validation cohort, 40 of 42 patients with a SPAAT score <3 achieved a complete cytoreduction, for a positive predictive value of 95.2 % and a negative predictive value of 100 %. Additionally, the SPAAT score was a significant predictor of disease-free survival.

CONCLUSIONS

The SPAAT score is a useful tool in the preoperative assessment of patients with LGMA who are under consideration for cytoreductive surgery. Prospective analysis of this scoring system is warranted to appropriately select patients who will benefit from CRS/HIPEC.

Clostridium difficile enteritis: A report of two cases and systematic literature review

Clostridium difficile (C. difficile) is the most common cause of healthcare associated infectious diarrhea. In the last decade, the incidence of C. difficile infection has increased dramatically. The virulence of C. difficile has also increased recently with toxigenic strains developing. C. difficile is generally a disease of the colon and presents with abdominal pain and diarrhea due to colitis. However, C. difficile enteritis has been reported rarely. The initial reports suggested mortality rates as high as 66%. The incidence of C. difficile enteritis appears to be increasing in parallel to the increase in colonic infections. We present two cases of patients who had otherwise uneventful abdominal surgery but subsequently developed C. difficile enteritis. Our literature review demonstrates 81 prior cases of C. difficile enteritis described in case reports. The mortality of the disease remains high at approximately 25%. Early recognition and intervention may reduce the high mortality associated with this disease process.

Primary pericardial mesothelioma in a 19-year-old presenting as pericarditis

Primary pericardial mesothelioma is a rare clinical entity. The association between asbestos and pericardial mesothelioma has not been well established, partly due to the small number of reported patients. Treatment options are limited for this very aggressive cancer. Surgical resection in the form of pericardiectomy can be curative, but owing to the frequently late presentation, surgical intervention is usually palliative. Chemotherapy and radiotherapy have overall poor results. We present the case of a 19-year-old man who initially had symptoms of pericarditis. He died 1 year after initial presentation.