Fragmentation of Care in Patients with Peritoneal Metastases Undergoing Cytoreductive Surgery

BACKGROUND

The delivery of multimodal treatment at a high-volume center is known to optimize the outcomes of gastrointestinal malignancies. However, patients undergoing cytoreductive surgery (CRS) for peritoneal metastases often must 'fragment' their surgical and systemic therapeutic care between different institutions. We hypothesized that this adversely affects outcomes.

PATIENTS AND METHODS

Adults undergoing CRS for colorectal or appendiceal adenocarcinoma at our institution between 2016 and 2022 were identified retrospectively and grouped by care network: 'coordinated care' patients received exclusively in-network systemic therapy, while 'fragmented care' patients received some systemic therapy from outside-network providers. Factors associated with fragmented care were also ascertained. Overall survival (OS) from CRS and systemic therapy-related serious adverse events (SAEs) were compared across the groups.

RESULTS

Among 85 (80%) patients, 47 (55%) had colorectal primaries and 51 (60%) received fragmented care. Greater travel distance [OR 1.01 (CI 1.00-1.02), p = 0.02] and educational status [OR 1.04 (CI 1.01-1.07), p = 0.01] were associated with receiving fragmented care. OS was comparable between patients who received fragmented and coordinated care in the colorectal [32.5 months versus 40.8 months, HR 0.95 (CI 0.43-2.10), p = 0.89] and appendiceal [31.0 months versus 27.4 months, HR 1.17 (CI 0.37-3.74), p = 0.55] subgroups. The frequency of SAEs (7.8% versus 17.6%, p = 0.19) was also similar.

CONCLUSIONS

There were no significant differences in survival or SAEs based on the networks of systemic therapy delivery. This suggests that patients undergoing CRS at a high-volume center may safely receive systemic therapy at outside-network facilities with comparable outcomes.

Western Diet-induced Transcriptional Changes in Anastomotic Tissue Is Associated With Early Local Recurrence in a Mouse Model of Colorectal Surgery

OBJECTIVE

To determine the timeframe and associated changes in the microenvironment that promote the development of a diet-induced local-regional recurrence in a mouse model of colorectal surgery.

BACKGROUND

Postoperative recurrence and metastasis occur in up to 30% of patients undergoing attempted resection for colorectal cancer (CRC). The underlying mechanisms that drive the development of postoperative recurrences are poorly understood. Preclinical studies have demonstrated a diet and microbial-driven pathogenesis of local-regional recurrence, yet the precise mechanisms remain undefined.

METHODS

BALB/C mice were fed a western diet (WD) or standard diet (SD), underwent a colon resection and anastomosis, given an Enterococcus faecalis enema on postoperative day (POD) 1, and subjected to a CT26 cancer cell enema (mimicking shed cancer cells) on POD2. Mice were sacrificed between POD3 and POD7 and cancer cell migration was tracked. Dynamic changes in gene expression of anastomotic tissue that were associated with cancer cell migration was assessed.

RESULTS

Tumor cells were identified in mice fed either a SD or WD in both anastomotic and lymphatic tissue as early as on POD3. Histology demonstrated that these tumor cells were viable and replicating. In WD-fed mice, the number of tumor cells increased over the early perioperative period and was significantly higher than in mice fed a SD. Microarray analysis of anastomotic tissue found that WD-fed mice had 11 dysregulated genes associated with tumorigenesis.

CONCLUSIONS

A WD promotes cancer cells to permeate a healing anastomosis and migrate into anastomotic and lymphatic tissue forming viable tumor nodules. These data offer a novel recurrence pathogenesis by which the intestinal microenvironment promotes a CRC local-regional recurrence.

Design and Implementation of a Learner-Centered Self-Paced Peritoneal Oncology Education Program

BACKGROUND

Current educational programs for peritoneal surface malignancies (PSM) are unstructured and often target advanced learners. The authors describe the design and implementation of a structured, self-paced course at a high-volume PSM center.

METHODS

In 2020, a learner-centered course was designed using the Canvas educational platform in consultation with the Center for Teaching at the University of Chicago. The course consisted of disease-site-specific modules, perioperative care pathways, in-built voluntary quizzes, and multimedia supplements for advanced learners. Trainees were provided access during the PSM service rotation, and engagement was compared across training levels by measuring the time spent online.

RESULTS

Course design and management required 71 h between 2020 and 2022, with the majority of time spent in the design phase. During 3 years, 62 personnel (21 [34%] medical students, 28 [45%] residents, 8 [13%] staff, and 5 [8%] fellows) were assigned the course. The overall engagement rate was 83.9% (86% of medical students, 75% of residents, 100% of staff and fellows), and the median time spent online was 12.4 min/week (interquartile range [IQR], 2.1-53.0 min/week). Fourth-year medical students and clinical fellows spent more time online than other learners (73 min/week [IQR, 24.5-100 min/week] vs 13.3 min/week [IQR, 7.3-26.5 min/week]) (p = 0.001).

CONCLUSIONS

The design and implementation of a PSM-specific course was feasible and sustainable using an online learning platform. Higher engagement was noted among invested learners. Non-technical factors for reduced engagement need to be ascertained further to improve the next iteration of this course.

Mutational profiles and prognostic impact in colorectal and high-grade appendiceal adenocarcinoma with peritoneal metastases

BACKGROUND

Next-generation sequencing (NGS) personalizes cancer treatments. In this study, we analyze outcomes based on NGS testing for colorectal cancer (CRC) and high-grade appendiceal adenocarcinoma (HGA) with peritoneal metastases.

METHODS

Retrospective review of genomic analyses and outcomes in patients with CRC or HGA with peritoneal metastases at a high-volume center from 2012 to 2019.

RESULTS

Ninety-two patients (57 CRC, 35 HGA) were identified. Overall survival was longer for CRC (52.8 vs. 30.5 months, p = 0.03), though rates of cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) were similar. Multiple genes were more frequently mutated in CRC, including KRAS (51% vs. 29%, p = 0.04), TP53 (47% vs. 20%, p < 0.01), and APC (46% vs. 6%, p < 0.01). For CRC, multivariate regression showed an increased hazard ratio (HR) with increasing peritoneal cancer index (1.06 [1.01-1.11], p = 0.02) and a decreased HR following CRS/HIPEC (0.30 [0.11-0.80], p = 0.02). PIK3CA mutation associated with significantly increased HR (3.62 [1.06-12.41], p = 0.04), though only in non-CRS/HIPEC patients. Multivariate analysis in the HGA group showed a benefit following CRS/HIPEC (0.18 [0.06-0.61], p = 0.01) and for mucinous disease (0.38 [0.15-0.96], p = 0.04), while there was an increased HR with TP53 mutation (6.89 [2.12-22.44], p < 0.01).

CONCLUSION

CRC and HGA with peritoneal spread have distinct mutational profiles. PIK3CA and TP53 mutations are associated with survival for CRC or HGA with peritoneal metastases, respectively.

Insurance Authorization Barriers in Patients Undergoing Cytoreductive Surgery and HIPEC

BACKGROUND

Indications for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) exist across multiple histologies, but little data exist on the impact of insurance authorization on access to these therapies. Given the evolving role of CRS/HIPEC, we sought to characterize insurance approval and delays in patients undergoing these therapies.

PATIENTS AND METHODS

A retrospective review was performed at a high-volume tertiary center of patients who received CRS/HIPEC from 2017 to 2021. Collected data included patient demographics, tumor histologic characteristics, insurance type, approval/denial history, and time to prior authorization approval. Descriptive statistics were performed.

RESULTS

In total, 367 patients received CRS/HIPEC during the study period. They had a median age of 59 (IQR 49-67) years, 35% were male, and 76% were white. Of the patients requiring prior authorization, 14 of 104 (13%) patients were denied prior authorization and required appeal. Median time between authorization request and approval was 33 (IQR 28-36) days. These cases generated 410 insurance authorization requests, 94 (23%) of which were not initially approved and required appeal. The rate of upfront denial was 21.1% in patients with public insurance compared with 23.4% in patients with private insurance. Gastric cancer was the most common histology among denied cases (55%), followed by colorectal, appendiceal, and gynecologic malignancies.

CONCLUSIONS

Despite the broadening indications for and data supporting CRS/HIPEC, a significant proportion of patients still face hurdles in attaining insurance approval and coverage for these therapies. Addressing barriers to insurance approval is imperative to decrease therapeutic delay and improve access to data-driven care.

Defeating Cancel Culture in Surgical Site Infection Research: A Plea to Include Microbial Cultures and Antibiotic Sensitivity Data

Background: Despite advances in infection control measures, surgical site infections (SSIs) remain a real and present danger to patients. In most studies addressing SSI prevention measures, recommendations are often made in the absence of information such as culture results, the antibiotic agents used for prophylaxis, and antibiotic sensitivity data. The aim of this study is to document this latter claim by reviewing studies published in the last five years in highly read and cited surgical journals. Methods: A systematic review evaluating SSIs from four highly cited surgical journals, Annals of Surgery, the British Journal of Surgery, JAMA Surgery, and the Journal of the American College of Surgeons was conducted for articles published between 2016 and 2021. We focused our analysis on the following key features: how SSI is defined; bacterial culture information; antibiotic sensitivity data; and identification of the antibiotic chosen for prophylaxis. We hypothesized that, in most cases among the journals queried, this information would be unavailable. Results: Of the 71 studies included, 32 diagnosed SSIs based on criteria developed by the U.S. Centers for Disease Control and Prevention while five provided no definition of SSI. Of the 27 articles recommending increasing antibiotic usage, only one study performed antibiotic sensitivity testing to guide the antibiotic choice. Of 71 studies reviewed, only one reported all key features we considered to be important for SSI antibiotic decision-making; 46 reported none of the key features. Conclusions: Among publications addressing SSIs in four highly cited surgical journals, key information regarding diagnosis and with which to base antibiotic recommendations, is routinely unavailable.

Impact of hyperthermic intraperitoneal chemotherapy on genomic heterogeneity of peritoneal metastases in stage IV gastroesophageal adenocarcinoma

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Background: Programmed death ligand 1 (PD-L1) expression and tumor mutational burden (TMB) are potential biomarkers for response to therapy. Heterogeneity of PD-L1 and TMB has been demonstrated in gastroesophageal adenocarcinoma (GEA) in response to systemic chemotherapy. With the increased use of hyperthermic intraperitoneal chemotherapy (HIPEC) for GEA peritoneal metastases (PM), we aimed to determine the effects of HIPEC on genomic heterogeneity of PM. Methods: This is a retrospective review of a prospectively maintained database of patients with stage IV GEA who underwent iterative laparoscopic HIPEC (mitomycin C 30 mg + cisplatin 200 mg, 60 minutes) between 2017 and 2021. PD-L1 status and TMB levels were reviewed from peritoneal tumor specimens collected prior to each HIPEC. PD-L1 status was defined as positive if combined positive score (CPS) was 1 or greater using the 22C3 pharmDx assay. TMB levels were defined as low, intermediate, or high for up to 5, 5 to 15, or over 15 mutations per megabase (m/MB), respectively. Potentially actionable and biologically relevant variants were reviewed, as well as overall survival, defined as time from diagnosis with stage IV disease to death from any cause. Results: 16 patients completed at least one HIPEC during the study period. Median age was 55.5 years (range 43-79), 50% were female, and 62.5% were Caucasian. All patients received at least one line of systemic chemotherapy after stage IV diagnosis and prior to first HIPEC. Median peritoneal cancer index at first HIPEC was 15 (range 3-39). Three patients completed only one HIPEC. Of the 13 who completed at least two HIPECs, 5 had sufficient tumor tissue for genomic analysis at two timepoints. Of those 5 patients, one exhibited a change in PD-L1 expression from positive to negative after HIPEC, and one exhibited an increase in TMB from low to intermediate. All 5 patients exhibited a change in the profile of potentially actionable or biologically relevant genetic variants, including gain or loss of mutations in DNA repair genes (RAD51), proto-oncogenes (MET), and tumor suppressor genes (ERBB3, IRS2). Median overall survival amongst the full cohort was 27.4 months, with median follow-up of 26.1 months. Overall survival was higher amongst those who underwent at least 2 HIPECs compared to only one, but this was not statistically significant. Conclusions: Amongst our cohort, only one patient exhibited a change in PD-L1 expression and one in TMB after HIPEC. However, HIPEC was associated with a change in genetic variant profiles in all evaluable patients. If confirmed in larger studies, this temporal genomic heterogeneity could inform the role of PD-L1, TMB, and other genetic variants as predictive biomarkers for therapy after HIPEC. Iterative laparoscopic HIPEC warrants further investigation as a treatment option after systemic therapy for GEA with peritoneal metastases.

Survival in total preoperative verus perioperative chemotherapy for patients with metastatic high-grade appendiceal adenocarcinoma undergoing CRS/HIPEC

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Background: Due to the relative infrequency of high grade appendiceal adenocarcinoma with peritoneal metastases, there is limited data to guide treatment strategies. Current practices for this disease are largely extrapolated from colon cancer patients with peritoneal metastases, who typically undergo six months of systemic chemotherapy in conjunction with cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). The optimal timing of chemotherapy in relation to CRS/HIPEC remains unknown. In this study, we compare the efficacy of peri-operative chemotherapy to pre-operative chemotherapy alone. Methods: This is a retrospective review of patients who underwent CRS/HIPEC for high grade appendiceal cancers from a tertiary referral center from 2014-2020. Outcomes were compared between patients who underwent planned 6 months of chemotherapy followed by CRS/HIPEC (pre-operative group) versus planned 3 months of chemotherapy both pre- and post-operatively (peri-operative group). Results: 85 patients were treated for metastatic high-grade appendiceal cancers during the study period, of whom24 were eligible for inclusion. Of those included, 16 were in the peri-operative group and 8 in the pre-operative group. Most patients were white (75%), non-Hispanic (96%) and female (54%). Patients in the pre-operative group tended to be older (65 vs. 56 years, p = 0.02). For patients with specified histologic grading, poorly differentiated tumors were common (50%). Signet ring cell histology (42%) and mucinous features (67%) were frequent as well. Median overall survival was similar between the pre-operative and peri-operative groups (32.3 vs. 31.6 months, p = 0.97), although patients undergoing peri-operative treatment received fewer total cycles of chemotherapy on average (14.1 vs. 9.5 cycles, p < 0.01). Half of the patients in the peri-operative group (8/16) did not complete their chemotherapy regimen, with 75% discontinuing therapy due to chemotherapy-related toxicities. Within the peri-operative group, a non-significant decrease in median survival was observed for those who did not complete chemotherapy (27.8 vs > 53.6 months, p = 0.22). Conclusions: Peri-operative and total pre-operative chemotherapy strategies are associated with similar survival in patients with high grade appendiceal cancers undergoing CRS/HIPEC. Peri-operative administration may be limited by chemotherapy-related toxicities.

Gastrointestinal Surgical Emergencies in the Neutropenic Immunocompromised Patient

Surgeons encounter neutropenic patients through elective or emergency consultation with increasing regularity. As medical management continues to extend the lives of patients with benign hematologic diseases, hematologic malignancies, solid malignancies, or iatrogenic neutropenia, more patients are presenting with infectious complications caused and/or complicated by their neutropenia. This leaves surgeons in the difficult position of managing medically fragile patients with unusual presentations of common disease processes. These patients often fall outside of classical guidelines and treatment pathways. Many studies addressing these issues are retrospective and non-randomized. Here, we review common emergency gastrointestinal surgery scenarios and their management in the setting of a neutropenic patient. While biliary disease, appendicitis, anorectal disease, and perforations will be covered in detail, an extensive appreciation of a patient's medical or oncologic disease course and appropriate utilization of consultants such as interventional radiology, gastroenterology, and hematology is often necessary.

Influence of race and sociodemographic factors on declining resection for gastric cancer: A national study

BACKGROUND

The purpose of this study was to determine whether racial or other demographic characteristics were associated with declining surgery for early stage gastric cancer.

METHODS

Patients with clinical stage I-II gastric adenocarcinoma were identified from the NCDB. Multivariable logistic models identified predictors for declining resection. Patients were stratified based on propensity scores, which were modeled on the probability of declining. Overall survival was evaluated using the Kaplan-Meier method.

RESULTS

Of 11,326 patients, 3.68% (n = 417) declined resection. Patients were more likely to refuse if they were black (p < 0.001), had Medicaid or no insurance (p < 0.001), had shorter travel distance to the hospital (p < 0.001) or were treated at a non-academic center (p = 0.001). After stratification, patients who declined surgery had worse overall survival (all strata, p < 0.001).

CONCLUSIONS

Racial and sociodemographic disparities exist in the treatment of potentially curable gastric cancer, with patients who decline recommended surgery suffering worse overall survival.

Fluoroquinolone and macrolide resistance in Campylobacter jejuni isolated from broiler slaughterhouses in southern Brazil

Campylobacter jejuni is recognized as a leading cause of acute bacterial gastroenteritis in humans. The over-use of antimicrobials in the human population and in animal husbandry has led to an increase in antimicrobial-resistant infections, particularly with fluoroquinolones and macrolides. The aim of the present study was to provide information of the current status of antimicrobial resistance patterns in Campylobacter jejuni from poultry sources. Fifty strains were recovered from broiler slaughterhouses in Rio Grande do Sul state, Brazil, 2012. The strains were investigated for antimicrobial susceptibility against three agents (ciprofloxacin, nalidixic acid and erythromycin) by minimal inhibitory concentrations. The strains were analysed by polymerase chain reaction-restriction fragment length polymorphism for detection of the Thr-86 mutation that confers resistance to ciprofloxacin. In addition, all the strains were tested for the presence of efflux systems (cmeB gene) conferring antimicrobial resistance. The minimum inhibitory concentrations results showed that 98% of isolates were sensitive to erythromycin and most isolates were resistant to ciprofloxacin (94%) and nalidixic acid (90%). A complete correlation was observed between the minimum inhibitory concentrations and PCR-RFLP assay. Finally, the cmeB gene that is responsible for multidrug resistance was detected in 16 isolates out the 50 strains (32%).

The usefulness of fiberoptic bronchoscopy in evaluating new pulmonary lesions in the compromised host

Thirty-four fiberoptic bronchoscopies employing various bronchoscopic technics were carried out in 33 immune-compromised patients for the evaluation of new pulmonary lesions. Transbronchial biopsy was performed only with fluoroscopic guidance and was omitted in patients with a bleeding tendency. Bronchial brushing and bronchial washing were successfully carried out despite the presence of contraindications to biopsy. Brushing and washing were diagnostically useful in 66 and 74 per cent of the cases, respectively, compared to 71 per cent for forceps biopsy. The combined over-all yield was 88 per cent, with no serious complications encountered. The most common etiology of new infiltrates was opportunistic infection. Among bacterial infections, gram-negative organisms were the most common, and among fungal etiologies, Coccidioides immitis was the predominant pathogen in this series from Tucson, Arizona. Although the roentgenographic pattern was not helpful in predicting the etiology of the new infiltrates, diffuse lesions were more frequently evaluated correctly by fiberoptic bronchoscopy than localized lesions. The low incidence of complications and the high over-all yield indicate that fiberoptic bronchoscopy, employing bronchial brushing and washing as supplements to transbronchial biopsy (and as a replacement to biopsy in patients with a bleeding diathesis), can be very useful in evaluating new pulmonary lesions in the immune-compromised patient. When used together, these technics significantly increase the diagnostic yield and eliminate the risks associated with performing more invasive diagnostic procedures in the compromised host.