Citations

Abstract Incidence rates for endometrial cancer (EC) are rising, particularly in postmenopausal and obese women. Our previous work has showed that the uterine and vaginal microbiome distinguishes patients with EC from those without. We now examine the impact of patient factors (such as menopause status, body mass index, and vaginal pH) in the microbiome in the absence of EC and how these might contribute to the microbiome signature in EC. We find that each factor independently alters the microbiome and identified postmenopausal status as the main driver of a polymicrobial network associated with EC (ECbiome). Of the 17 taxa we found enriched in EC patients, 8 were also enriched by postmenopause. Because postmenopausal status is a main risk factor for endometrial cancer, this system can be thought of as an ecological succession towards a disease state. Organisms within the ECbiome have been previously identified as polymicrobial associations in chronic soft tissue infections, ulcers, morbid obesity, and bacterial vaginosis. This suggests that this microbiome network is likely involved in mechanisms of host disease. Within the ECbiome, Porphyromonas somerae stands out because of its very significant and specific association with EC (p = 5.73E-6; Q = 0.009). We had previously identified this species as significantly associated with EC, and hereby validate that finding. Because the association of P. somerae with EC was robust and specific enough to potentially be considered as a biomarker for the disease (AUC 76.7%, CI: 67.9-85.5%), we developed a P. somerae-specific qPCR assay to detect this species in vaginal swabs. This becomes of particular interest because the lower tract and uterine microbiome are significantly correlated in these patients (p = 0.01), indicating that the vaginal microbiome can be used as a proxy for the uterine environment in EC. In agreement with the 16S rRNA gene sequencing data, P. somerae was detected significantly more frequently in vaginal swabs of patients with EC than those without EC (p = 3.02E-7). Overall, the test achieved a sensitivity of 74% and specificity of 63%, with a positive predictive value of 0.86 for obese and postmenopausal patients. In summary, we identify Porphyromas somerae presence as the most predictive microbial marker of EC, and we confirm this using targeted qPCR, which could be of use in detecting EC in high-risk, asymptomatic women. Given the established pathogenic behavior of P.somerae, we have also explored mechanistic routes through which this microbe and associated consortia may be involved in the mechanisms of disease. Citation Format: Marina Walther-Antonio, Dana Walsh, Alexis Hokenstad, Jun Chen, Jayeun Sung, Gregory Jenkins, Nicholas Chia, Heidi Nelson, Andrea Mariani. Postmenopause as a key factor in the composition of the Endometrial Cancer Microbiome (ECbiome): Putative role of Porphyromonas somerae in the disease [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr PR09.

AbstractBackground and ObjectiveWhether bowel preparation utilization rates or effectiveness varies based on tumor location is unknown.MethodsThe 2012–2016 American College of Surgeons National Surgical Quality Improvement Program Colectomy Targeted participant user file was queried for patients undergoing elective colorectal resection for cancer. Bowel preparation was classified as combined, mechanical bowel preparation alone, oral antibiotic alone, or none. Cochran–Armitage tests were used for trend analysis. Multivariable analyses stratified by tumor location were performed for the outcome of anastomotic leak. An additional multivariable model including all tumor locations assessed for interaction between bowel preparation and tumor location on an anastomotic leak.ResultsA total of 29,739 operations were included and the anastomotic leak rate was 1.9% with combined preparation versus 4.0% without preparation. Combined bowel preparation utilization increased over time as tumor location became more distal (both p < .0001). However, the adjusted effect of combined bowel preparation on anastomotic leak risk reduction did not differ by individual tumor location or across all tumor locations (p = .43 for interaction).ConclusionThough the utilization rate of combined bowel preparation increased as tumor location became more distal, its risk‐reducing effect remained similar. Quality improvement initiatives should focus on increased utilization of combined bowel preparation with an emphasis on tumors in the ascending colon.

From the onset of the COVID-19 global pandemic of 2020, the American College of Surgeons has been a leader in disseminating reliable information on the nature of the crisis and assuring quality of surgical care during the enforced lockdown of inpatient and outpatient care.

e15635 Background: Most squamous cell carcinomas of the anal canal (SCC) respond to chemoradiation, but effective therapy for locally-invasive(T4) or recurrent disease that fails standard chemoradiation and/or salvage abdominoperineal resection (APR) has not been clearly delineated. A multimodality approach including chemoradiation, extended pelvic resection and intraoperative radiation therapy (IORT) was assessed for survival impact and treatment morbidity.morbidities. Methods: A prospective registry including 26 patients with locally-invasive or recurrent disease treated between 1993 and 2007 was reviewed. Primary endpoint was overall survival (OS), obtained from prospectively collected patient questionnaires and medical record review, and analyzed by the Kaplan-Meier method. Short (60-day postoperative) and long-term (median followup: 1.6 years; 5.3 years among survivors) complications were assessed. Results: Patients (median age: 51 years) presented with (1) locally-invasive disease that persisted despite initial standard chemoradiation (n=10, 39%), (2) disease that recurred after initial standard chemoradiation (n=10, 39%; median 1.7 years to recurrence), or (3) re-recurrence after a salvage APR (n=6, 23%; median 1.3 years since APR). All patients received chemotherapy and external beam radiation preoperatively, and 19% received additional postoperative chemoradiation. Gross pelvic disease was completely resected in all (R0 in 73%; R1 in 27%). IORT (750–3250cGy) was delivered at single (92%) or two sites (8%). Median overall survival (OS) was 1.7 years. Five-year OS were: 50%, 10%, and 22% for patients with locally-invasive, recurrent, and re-recurrent disease respectively. Short-term complications predominantly related to the perineal wound. Fifteen patients reported long-term complications (>grade3): bowel obstruction in 8 (1 requiring operation), perineal wound fistula/non-healing in 9, leg paresthesia in 5, hydronephrosis in 3. Conclusions: For select patients with locally-persistent or recurrent SCC who fail standard primary treatment, a multimodality approach involving chemoradiation, extended pelvic resection and IORT offers a chance for improved survival. No significant financial relationships to disclose.

2022 Background: Studies have suggested superior outcomes for patients with cancer treated at National Cancer Institute (NCI) and academic hospitals, leading some to advocate for complex cancer care to be delivered at regional referral centers. However, growing demand at such centers may exceed their capacity to provide timely treatment, which could be detrimental to patient outcomes. We evaluated the relationship between hospital type, the average annual growth rate in patient volume (PV), and time to treatment initiation (TTI) trends. Methods: We used the National Cancer Database to identify patients undergoing initial treatment for a new diagnosis of cancer (breast, lung, prostate, colorectal, melanoma, bladder, non-Hodgkin lymphoma, renal, uterine or pancreatic) in 2007-2016. The exposure was hospital type (NCI, academic, community or integrated network). The primary outcome was TTI over time. We estimated both the average annual growth rate for PV and adjusted TTI trends by hospital type using linear mixed effects models, including a hospital type-by-time interaction and, when modeling TTI, a patient volume-by-time interaction. Results: We identified 4,218,577 patients treated at 1351 hospitals (49% at 897 community, 23% at 177 academic, 14% at 50 NCI and 14% at 227 integrated network hospitals). Over the study period, PV grew by 40% at NCI and 25% at academic hospitals, compared to 8% at community hospitals (p-value for trend both < 0.001). Meanwhile, mean TTI increased by 3.2 days at community, remained stable at academic (+0.3 days) and decreased by 4.3 days at NCI hospitals (p-value for trend both < 0.001 vs community). A higher annual PV growth rate was associated with a statistically but not clinically significant TTI increase (0.05 days for each 100 patient/year increase in the growth rate, p = 0.001). Conclusions: Patients with newly diagnosed cancer are increasingly receiving treatment at NCI and academic hospitals. While TTI at NCI and academic hospitals is longer than in the community, PV growth has been possible without delaying cancer treatment. Further study is needed to determine whether continued growth at this rate is sustainable. [Table: see text]

Background The purpose of this study is to describe our experience and outcomes in oncoplastic pelvic reconstruction for patients who underwent either vertical rectus abdominis musculocutaneous (VRAM) or omental flap following abdominoperineal resection (APR) at a single tertiary care institution. Methods All patients who underwent pelvic reconstruction following APR with either VRAM or omental flaps from January 1992 to January 2017 were retrospectively reviewed. Patient demographics and relevant comorbidities including chemotherapy and radiation therapy data were collected and analyzed. In addition, margin status at the time of oncologic resection was analyzed. Flap-specific data were collected for each approach. Oncologic data collected included cancer type, stage at time of APR, and rate of tumor recurrence within the flap. Results A total of 562 patients were identified who underwent pelvic reconstruction with either VRAM or omental pedicle flaps. Of these, 274 (48.8%) underwent VRAM reconstruction and 288 (51.2%) underwent omental flap reconstruction. All margins were negative at time of cancer ablation surgery. Complications data included: seroma (VRAM = 2 [0.36%]; omentum = 32 [5.69%], p < 0.0001), wound dehiscence (VRAM = 31 [5.52%]; omentum = 17 [3.02%], p = 0.022), abscess (VRAM = 4 [0.71%]; omentum = 27 [4.8%], p < 0.0001), cellulitis (VRAM = 2 [0.36%]; omentum = 10 [1.78%], p = 0.025). Statistical comparison of tumor recurrence between these two reconstructive approaches showed a significantly higher recurrence rate in omental flaps compared with VRAM flaps (p = 0.000127). Conclusion The results of this study suggest a significantly higher tumor recurrence rate in omental flap pelvic reconstruction compared with VRAM flaps. This knowledge has the potential to influence surgical planning and flap selection in pelvic reconstruction.

Objective: Surgeon workload, or human “cost” of performing a procedure, is not well understood in light of emerging surgical technologies. This pilot study quantified surgeon workload for colorectal procedures and identified patient, surgeon, and procedural factors impacting workload. Summary Background Data: Innovative technologies and procedures in surgery have generally been promoted for the advancement of patient care. The resulting surgeon workload is poorly studied with little knowledge of the contributing factors impacting workload. Methods: Surgeons completed NASA-Task Load Index (NASA-TLX) questionnaires to self-assess workload following abdominopelvic colon and rectal procedures. Corresponding patient data were retrieved from the medical record. Descriptive statistics, correlations, and ANOVA were performed to compare surgeon and patient factors, procedure type, and surgical approach on workload overall and by subscales. Results: Seven attending surgeons rated 238 surgeries, of which 218 (92%) had corresponding patient data. Surgeon experience and patient demographics had inconsistent effects on workload. A statistically significant 3-way interaction was identified among disease process, procedure type, and surgical approach on workload (F(9, 146) = 2.17, P = 0.027), but was limited to open procedures for neoplasia and inflammatory bowel disease patients. Proctectomy and colectomy procedures compared across open, laparoscopic, and robotic approaches showed significant differences in overall workload and subscales, where the robotic procedures required significantly less mental demand, physical demand, and effort, than open or laparoscopic ( P < 0.05). Conclusions: Patient characteristics, disease process, and surgical experience had inconsistent effects on surgeon workload. Major differences in workload were identified for procedure type and surgical approach, where robotic procedures required less mental demand, physical demand, and effort.