Multi-Institutional Study Evaluating the Role of Circulating Tumor DNA in the Management of Appendiceal Cancers.

PURPOSE: Conventional surveillance methods are poorly sensitive for monitoring appendiceal cancers (AC). This study investigated the utility of circulating tumor DNA (ctDNA) in evaluating systemic therapy response and recurrence after surgery for AC. METHODS: Patients from two specialized centers who underwent tumor-informed ctDNA testing (Signatera) were evaluated to determine the association between systemic therapy and ctDNA detection. In addition, the accuracy of ctDNA detection during surveillance for the diagnosis of recurrence after complete cytoreductive surgery (CRS) for grade 2-3 ACs with peritoneal metastases (PM) was investigated. RESULTS: In this cohort of 94 patients with AC, most had grade 2-3 tumors (84.0%) and PM (84.0%). Fifty patients completed the assay in the presence of identifiable disease, among which ctDNA was detected in 4 of 7 (57.1%), 10 of 16 (62.5%), and 19 of 27 (70.4%) patients with grade 1, 2, and 3 diseases, respectively. Patients who had recently received systemic chemotherapy had ctDNA detected less frequently (7 of 16 [43.8%] v 26 of 34 [76.5%]; odds ratio, 0.22 [95% CI, 0.06 to 0.82]; P = .02). Among 36 patients with complete CRS for grade 2-3 AC-PM, 16 (44.4%) developed recurrence (median follow-up, 19.6 months). ctDNA detection was associated with shorter recurrence-free survival (median 11.3 months v not reached; hazard ratio, 14.1 [95% CI, 1.7 to 113.8]; P = .01) and showed high accuracy for the detection of recurrence (sensitivity 93.8%, specificity 85.0%). ctDNA was more sensitive than carcinoembryonic antigen (62.5%), CA19-9 (25.0%), and CA125 (18.8%) and was the only elevated biomarker in four (25%) patients with recurrence. CONCLUSION: This study revealed a reduced ctDNA detection frequency after systemic therapy and accurate recurrence assessment after CRS. These findings underscore the role of ctDNA as a predictive and prognostic biomarker for grade 2-3 AC-PM management.

Outcomes of parenteral nutrition in patients with advanced cancer and malignant bowel obstruction.

BACKGROUND: Malignant bowel obstruction (MBO) affects 3% to 15% of all cancer patients. In patients with advanced cancer and inoperable MBO, the average survival varies between four to nine weeks. Parenteral nutrition (PN) may improve survival in specific patient populations with malignant bowel obstruction. AIMS: This retrospective, single-center cohort study aimed to review individual patient outcomes on PN in the setting of advanced cancer with a diagnosis of MBO and identify clinical and laboratory markers predictive of short- and long-term survival to further highlight patients that would benefit from PN in the setting of an inoperable MBO. RESULTS: In a retrospective analysis of 68 patients receiving PN for inoperable MBO, the median survival was 142 (IQR: 63.3-239.5) days. Patients experienced a median number of two hospital readmissions (range: 0-10) and spent a median of 29 days (range: 0-105) in the hospital after starting PN. Eighteen (26.5%) patients developed a catheter-related bloodstream infection (CRBSI). A diagnosis of appendiceal cancer was identified as a predictive marker of improved survival (HR: 0.53, 95% CI: 0.29-0.92, p = 0.023). CONCLUSIONS: The use of PN in the context of end-of-life cancer care is a practice that necessitates improvement. Recognizing the outcomes and patient experiences of PN utilization is essential to physicians and patients.

Implementation of a high-resolution, high-contrast magnetic resonance imaging protocol with extended delayed phases for peritoneal mesothelioma.

Background: Imaging of peritoneal malignancies using conventional cross-sectional imaging is challenging, but accurate assessment of peritoneal disease burden could guide better selection for definitive surgery. Here we demonstrate feasibility of high-resolution, high-contrast magnetic resonance imaging (MRI) of peritoneal mesothelioma and explore optimal timing for delayed post-contrast imaging. Methods: Prospective data from inpatients with malignant peritoneal mesothelioma (MPM), imaged with a novel MRI protocol, were analyzed. The new sequences augmenting the clinical protocol were (I) pre-contrast coronal high-resolution T2-weighted single-shot fast spin echo (COR hr T2w SSH FSE) of abdomen and pelvis; and (II) post-contrast coronal high-resolution three-dimensional (3D) T1-weighted modified Dixon (COR hr T1w mDIXON) of abdomen, acquired at five delay times, up to 20 min after administration of a double dose of contrast agent. Quantitative analysis of contrast enhancement was performed using linear regression applied to normalized signal in lesion regions of interest (ROIs). Qualitative analysis was performed by three blinded radiologists. Results: MRI exams from 14 participants (age: mean ± standard deviation, 60±12 years; 71% male) were analyzed. The rate of lesion contrast enhancement was strongly correlated with tumor grade (cumulative nuclear score) (r=-0.65, P<0.02), with 'early' delayed phase (12 min post-contrast) and 'late' delayed phase (19 min post-contrast) performing better for higher grade and lower grade tumors, respectively, in agreement with qualitative scoring of image contrast. Conclusions: High-resolution, high-contrast MRI with extended post-contrast imaging is a viable modality for imaging peritoneal mesothelioma. Multiple, extended (up to 20 min post-contrast) delayed phases are necessary for optimal imaging of peritoneal mesothelioma, depending on the grade of disease.

Venous Thromboembolism in Peritoneal Mesothelioma: Uncovering the Hidden Risk.

INTRODUCTION: Venous thromboembolism (VTE) is a common complication in patients with abdominal malignancies. Despite known associations between pleural mesothelioma and increased VTE risk, the characteristics of VTE in patients with peritoneal mesothelioma (PeM) remain undescribed. METHODS: Patients treated for PeM were retrospectively identified from our institutional database. The frequency of VTE was assessed and logistic regression modeling was employed to assess VTE risk factors. The association between VTE and overall survival was also ascertained. Recommended thromboprophylaxis for patients who underwent surgery at our institution comprised a single preoperative dose of prophylactic anticoagulation, followed by daily dosing for four weeks postoperatively. RESULTS: Among 120 PeM patients, 26 (21.7%) experienced VTE, including 19/91 (20.9%) surgical patients, 4/23 (17.4%) patients who received systemic therapy, and 3/6 (50%) patients who underwent observation (p = 0.21). Most events were symptomatic (n = 16, 62%) and were attributable to pulmonary emboli (n = 16, 62%). The 90-day postoperative VTE rate was 4.4% (4/91), including 1 of 60 patients who underwent index surgical intervention at our institution and 3 patients with surgery elsewhere. A low serum albumin concentration was associated with VTE in non-surgical patients (odds ratio 0.12, confidence interval [CI] 0.02-0.72; p = 0.03). No significant difference in overall survival was observed between patients with and without VTE (median 46.0 months [CI 24.9-67.0] vs. 55.0 months [CI 27.5-82.5]; hazard ratio 0.98 [CI 0.54-1.81], p = 0.98). CONCLUSIONS: A high risk of VTE was observed in PeM patients, warranting suspicion throughout the disease trajectory. Postoperative VTE rates were within acceptable limits with 4-week thromboprophylaxis.

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

BACKGROUND: Plasma circulating tumor DNA (ctDNA) is a promising biomarker for metastatic colorectal cancer (mCRC); however, its role in characterizing recurrence sites after mCRC resection remains poorly understood. This single-institution study investigated the timing of ctDNA detection and its levels in the context of recurrence at different sites after mCRC resection. STUDY DESIGN: Patients who underwent optimal resection of CRC metastases involving the peritoneum, distant lymph nodes, or liver, with serial postoperative tumor-informed ctDNA assessments (Signatera) were included. Recurrence sites, as defined by surveillance imaging or laparoscopy, were categorized as peritoneal-only and other distant sites (liver, lung, lymph nodes, or body wall). RESULTS: Among the 31 included patients, ctDNA was detected in all 26 (83.4%) patients with postoperative recurrence and was persistently undetectable in 5 patients who did not experience recurrence. At 3 months postsurgery, ctDNA was detected in 2 (25%) of 8 patients with peritoneal-only recurrence and 17 (94.4%) of 18 patients with distant recurrence (p < 0.001). Beyond 3 months, ctDNA was detected in the remaining 6 patients with peritoneal-only disease and 1 patient with distant disease. ctDNA detection preceded the clinical diagnosis of recurrence by a median of 9 weeks in both groups. At recurrence, peritoneal-only recurrent cases exhibited lower ctDNA levels (median 0.4 mean tumor molecules/mL, interquartile range 0.1 to 0.8) compared with distant recurrence (median 5.5 mean tumor molecules/mL, interquartile range 0.8 to 33.3, p = 0.004). CONCLUSIONS: Peritoneal-only recurrence was associated with delayed ctDNA detection and low levels of ctDNA after optimal resection for mCRC. ctDNA testing may effectively characterize recurrence sites and may help guide subsequent treatments specific to the disease sites involved.

Novel Application of a Dynamic, In-room Survey Platform to Measure Surgical Team Satisfaction.

OBJECTIVE: To elucidate the potential usage of continuous feedback regarding team satisfaction and correlations with operative performance and patient outcomes. BACKGROUND: Continuous, actionable assessment of teamwork quality in the operating room (OR) is challenging. This work introduces a novel, data-driven approach to prospectively and dynamically assess health care provider satisfaction with teamwork in the OR. METHODS: Satisfaction with teamwork quality for each case was assessed utilizing a validated prompt displayed on HappyOrNot Terminals placed in all ORs, with separate panels for circulators, scrub nurses, surgeons, and anesthesia providers. Responses were cross-referenced with OR log data, team familiarity indicators, efficiency parameters, and patient safety indicator events through continuous, semiautomated data marts. Deidentified responses were analyzed through logistic regression modeling. RESULTS: Over a 24-week period, 4123 responses from 2107 cases were recorded. The overall response rate per case was 32.5%. Greater scrub nurse specialty experience was strongly associated with satisfaction (odds ratio: 2.15, 95% CI: 1.53-3.03, P < 0.001). Worse satisfaction was associated with longer than expected procedure time (odds ratio: 0.91, 95% CI: 0.82-1.00, P = 0.047), nighttime (0.67, 95% CI: 0.55-0.82, P < 0.001), and add-on cases (0.72, 95% CI: 0.60-0.86, P < 0.001). Higher material costs (22%, 95% CI: 6-37, P = 0.006) were associated with greater team satisfaction. Cases with superior teamwork ratings were associated with a 15% shorter length of hospital stay (95% CI: 4-25, P = 0.006). CONCLUSIONS: This study demonstrates the feasibility of a dynamic survey platform to report actionable health care provider satisfaction metrics in real-time. Team satisfaction is associated with modifiable team variables and some key operational outcomes. Leveraging qualitative measurements of teamwork as operational indicators may augment staff engagement and measures of performance.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy postoperative symptomatology: palliative care impact.

OBJECTIVES: Palliative care (PC) for patients with advanced cancer has been associated with improved symptom burden and quality of life (QoL). This study aimed to characterise postoperative symptoms of cytoreductive surgery (CRS)/hyperthermic intraperitoneal chemotherapy (HIPEC) patients and to assess PC impact by analysing symptom burden before and after PC interventions. METHODS: CRS/HIPEC patients with two PC visits within 5 months postoperatively (2016-2021) at a tertiary care centre were identified from a retrospective database. For each patient, documentation of QoL-associated symptoms at the initial PC visit and changes in symptomatology at the second PC visit were recorded. Descriptive statistics were performed. RESULTS: 46 patients were included in this study. Median age was 62.2 (range 31.9-84.6) years. Median peritoneal cancer index was 23.5 (range 0-39). The most common histologies were colorectal (32.6%) and appendiceal (30.4%). Symptoms most frequently reported were pain (84.8%), fatigue (54.3%) and appetite loss/change (52.2%). Following PC interventions, most symptoms were stable or improved. The mean number of symptoms per patient was 3.7, with an average of 3.5 improved/stable and 0.5 worse/new onset at follow-up (p<0.001). CONCLUSION: CRS/HIPEC patients experienced a high QoL-associated symptom burden. Following postoperative PC interventions, significantly more symptoms were reported as improved/stable, compared with worse/new onset.

Mesothelioma in situ of the peritoneum: report of three cases and review of the literature.

AIM: Diagnosis of mesothelioma in situ (MIS) is historically controversial and, until recently, specific features defining the entity have not been well characterized. Most reported cases of MIS occurred in the pleura; peritoneal MIS is very rare. This study investigates the morphologic features and results of ancillary testing in peritoneal MIS. METHODS: We present three patients with peritoneal MIS, as defined by a single layer of mesothelial cells with loss of nuclear BRCA-1-associated protein-1 (BAP1) immunostaining and without evidence of invasive tumour by microscopic evaluation, imaging, or direct examination of the peritoneum. Histology and immunostains were reviewed by three expert thoracic pathologists with multidisciplinary input. Next-generation sequencing (NGS) was performed in all three cases. A literature review was conducted to characterize this rare precursor lesion. RESULTS: BAP1 was lost in all three lesions, while methylthioadenosine phosphorylase (MTAP) was retained in two (not performed in the third). NGS revealed BAP1 pathogenic alterations in all three cases as well as mutations of SMO, ERCC3, TET2, and U2AF1. Progression to invasive mesothelioma occurred in one patient at 13 months postdiagnosis (case 1). One patient was diagnosed at age 24 and was later found to harbour a BAP1 germline mutation (case 3). CONCLUSION: This work describes the histologic features and clinicopathologic characteristics of peritoneal MIS in three cases, highlights BAP1 somatic and germline mutations in peritoneal MIS, and strengthens the importance of ancillary studies (including immunohistochemical and molecular studies) in the diagnosis of MIS.

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.

Early Integrated Palliative Care Within a Surgical Oncology Clinic.

Importance: Advance directive (AD) designation is an important component of advance care planning (ACP) that helps align care with patient goals. However, it is underutilized in high-risk surgical patients with cancer, and multiple barriers contribute to the low AD designation rates in this population. Objective: To assess the association of early palliative care integration with changes in AD designation among patients with cancer who underwent surgery. Design, Setting, and Participants: This cohort study was a retrospective analysis of a prospectively maintained registry of adult patients who underwent elective surgery for advanced abdominal and soft tissue malignant tumors at a surgical oncology clinic in a comprehensive cancer center with expertise in regional therapeutics between June 2016 and May 2022, with a median (IQR) postoperative follow-up duration of 27 (15-43) months. Data analysis was conducted from December 2022 to April 2023. Exposure: Integration of ACP recommendations and early palliative care consultations into the surgical workflow in 2020 using electronic health records (EHR), preoperative checklists, and resident education. Main Outcomes and Measures: The primary outcomes were AD designation and documentation. Multivariable logistic regression was performed to assess factors associated with AD designation and documentation. Results: Among the 326 patients (median [IQR] age 59 [51-67] years; 189 female patients [58.0%]; 243 non-Hispanic White patients [77.9%]) who underwent surgery, 254 patients (77.9%) designated ADs. The designation rate increased from 72.0% (131 of 182 patients) before workflow integration to 85.4% (123 of 144 patients) after workflow integration in 2020 (P = .004). The AD documentation rate did not increase significantly after workflow integration in 2020 (48.9% [89 of 182] ADs documented vs 56.3% [81 of 144] ADs documented; P = .19). AD designation was associated with palliative care consultation (odds ratio [OR], 41.48; 95% CI, 9.59-179.43; P < .001), palliative-intent treatment (OR, 5.12; 95% CI, 1.32-19.89; P = .02), highest age quartile (OR, 3.79; 95% CI, 1.32-10.89; P = .01), and workflow integration (OR, 2.05; 95% CI, 1.01-4.18; P = .048). Patients who self-identified as a race or ethnicity other than non-Hispanic White were less likely to have designated ADs (OR, 0.36; 95% CI, 0.17-0.76; P = .008). AD documentation was associated with palliative care consulation (OR, 4.17; 95% CI, 2.57- 6.77; P < .001) and the highest age quartile (OR, 2.41; 95% CI, 1.21-4.79; P = .01). Conclusions and Relevance: An integrated ACP initiative was associated with increased AD designation rates among patients with advanced cancer who underwent surgery. These findings demonstrate the feasibility and importance of modifying clinical pathways, integrating EHR-based interventions, and cohabiting palliative care physicians in the surgical workflow for patients with advanced care.

Global Cancer Surgery: pragmatic solutions to improve cancer surgery outcomes worldwide.

The first Lancet Oncology Commission on Global Cancer Surgery was published in 2015 and serves as a landmark paper in the field of cancer surgery. The Commission highlighted the burden of cancer and the importance of cancer surgery, while documenting the many inadequacies in the ability to deliver safe, timely, and affordable cancer surgical care. This Commission builds on the first Commission by focusing on solutions and actions to improve access to cancer surgery globally, developed by drawing upon the expertise from cancer surgery leaders across the world. We present solution frameworks in nine domains that can improve access to cancer surgery. These nine domains were refined to identify solutions specific to the six WHO regions. On the basis of these solutions, we developed eight actions to propel essential improvements in the global capacity for cancer surgery. Our initiatives are broad in scope, pragmatic, affordable, and contextually applicable, and aimed at cancer surgeons as well as leaders, administrators, elected officials, and health policy advocates. We envision that the solutions and actions contained within the Commission will address inequities and promote safe, timely, and affordable cancer surgery for every patient, regardless of their socioeconomic status or geographic location.

Outcomes of parenteral nutrition in patients with advanced cancer and malignant bowel obstruction.

Background: Malignant bowel obstruction (MBO) affects 3-15% of all cancer patients. In patients with advanced cancer and inoperable MBO, the average survival varies between four to nine weeks. Parenteral nutrition (PN) may improve survival in specific patient populations with malignant bowel obstruction. Aims: This retrospective, single-center cohort study aimed to review individual patient outcomes on PN in the setting of advanced cancer with a diagnosis of MBO and identify clinical and laboratory markers predictive of short- and long-term survival to further highlight patients that would benefit from PN in the setting of an inoperable MBO. Results: In a retrospective analysis of 68 patients receiving PN for inoperable MBO, the median survival was 142 (IQR: 63.3-239.5) days. Patients experienced a median number of two hospital readmissions (range: 0-10) and spent a median of 29 days (range: 0-105) in the hospital after starting PN. Eighteen (26.5%) patients developed a catheter-related bloodstream infection (CRBSI). A diagnosis of appendiceal cancer was identified as a predictive marker of improved survival (HR: 0.53, 95% CI: 0.29-0.92, p = 0.023). Conclusions: The use of PN in the context of end-of-life cancer care is a practice that necessitates improvement. Recognizing the outcomes and patient experiences of PN utilization is essential to physicians and patients.

Role of colectomy in the management of appendiceal tumors: a retrospective cohort study.

BACKGROUND: Appendiceal tumors represent a range of histologies that vary in behavior. Recommendations for treatment with appendectomy versus right hemicolectomy (RHC) for different tumor types are evolving and sometimes conflicting. This study sought to characterize variation in the United States around surgical treatment of major appendiceal tumor types over time and describe differences in outcomes based on procedure. METHODS: Patients diagnosed with appendiceal goblet cell adenocarcinoma (GCA), mucinous adenocarcinoma, neuroendocrine neoplasm (NEN), or non-mucinous adenocarcinoma from 2004-2017 were identified in the National Cancer Database. Trends in RHC over time and predictors of RHC were identified. Surgical outcomes for each histologic type and stage were compared. RESULTS: Of 18,216 patients, 11% had GCAs, 34% mucinous adenocarcinoma, 31% NENs, and 24% non-mucinous adenocarcinoma. Rate of RHC for NEN decreased from 68% in 2004 to 40% in 2017 (p = 0.008) but remained constant around 60-75% for other tumor types. Higher stage was associated with increased odds of RHC for all tumor types. RHC was associated with higher rate of unplanned readmission (5% vs. 3%, p < 0.001) and longer postoperative hospital stay (median 5 days vs. 3 days, p < 0.001). On risk-adjusted analysis, RHC was significantly associated with increased survival versus appendectomy for stage 2 disease of all tumor types (HRs 0.43 to 0.63) and for stage 1 non-mucinous adenocarcinoma (HR = 0.56). CONCLUSIONS: Most patients with appendiceal tumors undergo RHC, which is associated with increased readmission, longer length of stay, and improved survival for stage 2 disease of all types. RHC should be offered selectively for appendiceal tumors.

Adoption of cytoreductive surgery in the management of peritoneal malignancies-Global trends.

Cytoreductive surgery (CRS) has now been accepted as an integral component in the management of gastrointestinal and gynecological cancers with peritoneal metastases. Since the adoption of CRS is influenced by access to advanced medical facilities, trained multidisciplinary teams, and funding, there is wide variability in incorporation of CRS into routine clinical practice between high- versus low- and middle-income countries. This review highlights the global trends in the adoption of CRS for peritoneal malignancies with a specific focus on the establishment of CRS programs and barriers to incorporate CRS into routine clinical care in low- and middle-income countries.

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.

Alignment of RVU Targets With Operating Room Block Time.

Background: Surgeon productivity is measured in relative value units (RVUs). The feasibility of attaining RVU productivity targets requires surgeons to have enough allocated block time to generate RVUs. However, it is unknown how much block time is required for surgeons to attain specific RVU targets. We aimed to estimate the effect of surgeon and practice environment characteristics (SPECs) on block time needed to attain fixed RVU targets. Methods: We computationally simulated individual surgeons' annual caseloads under a variety of SPECs in the following way. First, empirical case data were sampled from ACS NSQIP in accordance with surgeon specialty, case-mix complexity, and RVU target. Surgeons' operating schedules were then constructed according to the block length, turnover time, and scheduling flexibility of the practice environment. These 6 SPECs were concurrently varied over their ranges for a 6-way sensitivity analysis. Results: Annual operating schedules for 60,000,000 surgeons were simulated. The number of blocks required to attain RVU targets varied significantly with surgeon specialty and increased with increased case-mix complexity, increased turnover time, and decreased scheduling flexibility. Intraspecialty variation in block requirement with variation in environmental characteristics exceeded interspecialty variation with fixed environmental characteristics. Multivariate linear models predicted block utilization across surgical specialties with consideration for the stated factors. An online tool is shared with which to apply these results to one's particular practice. Conclusions: Block time required to attain RVU targets varies widely with SPECs; intraspecialty variation exceeds interspecialty variation. The feasibility of attaining RVU targets requires alignment between targets and allocated operating time with consideration for surgical specialty and other practice conditions.

Surgical management of peritoneal metastasis: Opportunities for pharmaceutical research.

Cytoreductive surgery (CRS) has emerged as a survival-extending treatment of peritoneal metastasis (PM); recent advances include using intraperitoneal chemotherapy (IPC) at normothermic or hyperthermic temperatures, or under pressure (CRS + IPC). Clinical CRS + IPC research has established its highly variable efficacy and suggested tumor size, tumor locations and presence of ascites as potential determinants. On the other hand, there is limited knowledge on the effects of pharmaceutical properties on treatment outcomes. The present study investigated the inter-subject variability of paclitaxel binding to proteins in patient ascites because some PM patients show accumulation of ascites and because activity and transport of highly protein-bound drugs such as paclitaxel are affected by protein binding. Ascites samples were collected from 26 patients and investigated for their protein contents using LC/MS/MS proteomics analysis and for the concentrations of total proteins and two major paclitaxel-binding proteins (human serum albumin or HSA and α-1-acid glycoprotein or AAG). The association constants of paclitaxel to HSA and AAG and the extent of protein binding of paclitaxel in patient ascites were studied using equilibrium dialysis. Proteomic analysis of four randomly selected samples revealed 288 proteins, >90% of which are also present in human plasma. Between 72% - 94% of paclitaxel was bound to proteins in patient ascites. The concentrations of HSA and AAG in ascites showed substantial inter-subject variations, ranging from 14.7 - 46.3 mg/mL and 0.13-2.56 mg/mL, respectively. The respective paclitaxel association constants to commercially available HSA and AAG were âˆ¼ 3.5 and âˆ¼ 120 mM. Calculation using these constants and the HSA and AAG concentrations in individual patient ascites indicated that these two proteins accounted for >85% of the total protein-binding of paclitaxel in ascites. The extensive drug binding to ascites proteins, by reducing the pharmacologically active free fraction, may lead to the diminished CRS efficacy in PM patients with ascites. Clinical advances in CRS + IPC have outpaced current knowledge of pharmaceutical properties in this setting. IPC, as a locally acting therapy, is subjected to processes different from those governing systemic treatments. This study, to our knowledge, is the first to illustrate the implications of drug properties in the CRS + IPC efficacy against PM. While drugs are now an integral part of PM patient management, there is limited pharmaceutical research in this treatment setting (e.g., effects of hyperthermia or pressure on drug transport or release from delivery systems, pharmacokinetics, pharmacodynamics). Hence, CRS + IPC of PM represents an area where additional pharmaceutical research can assist further development and optimization.

Germline Variants Incidentally Detected via Tumor-Only Genomic Profiling of Patients With Mesothelioma.

Importance: Patients with mesothelioma often have next-generation sequencing (NGS) of their tumor performed; tumor-only NGS may incidentally identify germline pathogenic or likely pathogenic (P/LP) variants despite not being designed for this purpose. It is unknown how frequently patients with mesothelioma have germline P/LP variants incidentally detected via tumor-only NGS. Objective: To determine the prevalence of incidental germline P/LP variants detected via tumor-only NGS of mesothelioma. Design, Setting, and Participants: A series of 161 unrelated patients with mesothelioma from a high-volume mesothelioma program had tumor-only and germline NGS performed during April 2016 to October 2021. Follow-up ranged from 18 months to 7 years. Tumor and germline assays were compared to determine which P/LP variants identified via tumor-only NGS were of germline origin. Data were analyzed from January to March 2023. Main Outcomes and Measures: The proportion of patients with mesothelioma who had P/LP germline variants incidentally detected via tumor-only NGS. Results: Of 161 patients with mesothelioma, 105 were male (65%), the mean (SD) age was 64.7 (11.2) years, and 156 patients (97%) self-identified as non-Hispanic White. Most (126 patients [78%]) had at least 1 potentially incidental P/LP germline variant. The positive predictive value of a potentially incidental germline P/LP variant on tumor-only NGS was 20%. Overall, 26 patients (16%) carried a P/LP germline variant. Germline P/LP variants were identified in ATM, ATR, BAP1, CHEK2, DDX41, FANCM, HAX1, MRE11A, MSH6, MUTYH, NF1, SAMD9L, and TMEM127. Conclusions and Relevance: In this case series of 161 patients with mesothelioma, 16% had confirmed germline P/LP variants. Given the implications of a hereditary cancer syndrome diagnosis for preventive care and familial counseling, clinical approaches for addressing incidental P/LP germline variants in tumor-only NGS are needed. Tumor-only sequencing should not replace dedicated germline testing. Universal germline testing is likely needed for patients with mesothelioma.