Chemotherapy-free treatment targeting fusions and driver mutations in KRAS wild-type pancreatic ductal adenocarcinoma, a case series

Background

KRAS wild-type (WT) pancreatic ductal adenocarcinoma (PDAC) represents a distinct entity with unique biology. The therapeutic impact of matched targeted therapy in these patients in a real-world setting, to date, is less established.

Objectives

The aim of our study was to review our institutional database to identify the prevalence of actionable genomic alterations in patients with KRAS-WT tumors and to evaluate the therapeutic impact of matched targeted therapy in these patients.

Design

We reviewed electronic medical records of patients with KRAS-WT PDAC and advanced disease (n = 14) who underwent clinical-grade tissue ± liquid next-generation sequencing (315-648 genes for tissue) between years 2015 and 2021.

Methods

Demographic and disease characteristics were summarized using descriptive parameters. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

Results

Of 236 PDAC patients, 14 had advanced/metastatic disease with KRAS-WT tumors. Median age at diagnosis was 66 years. There was a high frequency of potentially actionable genomic alterations, including three (21%) with BRAF alterations, two (14%) with fusions [RET-PCM1 and FGFR2-POC1B (N = 1 each)]; and one with a druggable EGFR (EGFR E746_A755delISERD) variant; two other patients had an STK11 and a MUTYH alteration. Five patients were treated with matched targeted therapy, with three having durable benefit: (i) erlotinib for EGFR-altered tumor, followed by osimertinib/capmatinib when MET amplification emerged (first-line therapy); (ii) pralsetinib for RET fusion (fifth line); and (iii) dabrafenib/trametinib for BRAF N486_P490del (third line). Duration of time on chemotherapy-free matched targeted therapy for these patients was 17+, 11, and 18+ months, respectively.

Conclusion

Sustained therapeutic benefit can be achieved in a real-world setting in a subset of patients with advanced/metastatic KRAS-WT PDAC treated with chemotherapy-free matched targeted agents. Prospective studies are warranted.

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.

Median arcuate ligament release at the time of pancreaticoduodenectomy or total pancreatectomy

BACKGROUND

Celiac artery compression can complicate the performance of pancreaticoduodenectomy or total pancreatectomy due to the need for ligation of the gastroduodenal artery. Median arcuate ligament release restores normal arterial flow to the liver, spleen, and stomach and may avoid complications related to poor perfusion of the foregut.

METHODS

All patients who underwent median arcuate ligament release for celiac artery compression at the time of pancreatectomy between 2009 and 2023 were reviewed. Pre- and postoperative computed tomography was used to categorize celiac artery compression by the extent of compression (types A [<50%], B [50%-80%], and C [>80%]).

RESULTS

Of 695 patients who underwent pancreatectomy, 22 (3%) had celiac artery compression, and a majority (17) were identified on preoperative imaging. Median celiac artery compression was 52% (interquartile range = 18); 8 (36%) patients had type A and 14 (64%) had type B compression with a median celiac artery compression of 39% (interquartile range = 18) and 59% (interquartile range = 14), respectively (P < .001). Postoperative imaging was available for 20 (90%) patients, and a reduction in the median celiac artery compression occurred in all patients: type A, 14%, and type B, 31%. Complications included 1 (5%) death after hospital discharge, 1 (5%) pancreatic fistula, 1 (5%) delayed gastric emptying, and 4 (18%) readmissions. No patient had evidence of a biliary leak or liver dysfunction.

CONCLUSION

Preoperative computed tomography allows accurate identification of celiac artery compression. Ligation of the gastroduodenal artery during pancreaticoduodenectomy or total pancreatectomy in the setting of celiac artery compression requires median arcuate ligament release to restore normal arterial flow to the foregut and avoid preventable complications.

Impact of Regional Metastasis on Survival for Patients with Nonfunctional Pancreatic Neuroendocrine Tumors: A Systematic Review

BACKGROUND

Controversy exists regarding the benefit of lymphadenectomy for nonfunctional pancreatic neuroendocrine tumors (NF-PNET).

PATIENTS AND METHODS

MEDLINE/PubMed, EMBASE, and the Cochrane Library were searched for studies of pancreatic neuroendocrine tumors (PNET) published between 1990 and 2021. Studies of functional PNET were excluded. Reported incidence of lymph node metastasis (LNM) and survival analysis of either disease-free survival (DFS) or overall survival (OS) were required for inclusion.

RESULTS

Overall, 52 studies analyzing 24,608 PNET met the inclusion criteria. The reported LNM rate for NF-PNET ranged from 7 to 64 % (median 24.5%). Reported LNM rates ranged from 7 to 51% (median 11%) for NF-PNET< 2 cm in 14 studies and 29-47% (median 38%) in NF-PNET > 2 cm. In total, 19 studies (66%) reported LNM to have a negative impact on DFS. Additionally, 21 studies (60%) reported LNM to have a negative impact on OS. Two studies investigating the impact of lymphadenectomy (LND) found LND had the greatest impact for large, high-grade tumors. The overall quality of available evidence was low as assessed by the Grading of Recommendations, Assessment, Development, and Evaluation System.

CONCLUSIONS

Published literature evaluating the impact of regional LNM and LND in PNET is confounded by heterogeneity in practice patterns and the retrospective nature of these cohort studies. Most studies suggest high rates of LNM in NF-PNET that negatively impact DFS and OS. Given the high rate of LNM in NF-PNET and its potential detrimental effect on DFS and OS, we recommend lymphadenectomy be completed for NF-PNET > 2 cm and strongly considered for NF-PNET < 2 cm.

Disparities in Mentorship and Implications for US Surgical Resident Education and Wellness

Importance

Many surgeons cite mentorship as a critical component of training. However, little evidence exists regarding factors associated with mentorship and the influence of mentorship on trainee education or wellness.

Objectives

To evaluate factors associated with surgical trainees' perceptions of meaningful mentorship, assess associations of mentorship with resident education and wellness, and evaluate programmatic variation in mentorship.

Design, Setting, and Participants

A voluntary, anonymous survey was administered to clinically active residents in all accredited US general surgery residency programs following the 2019 American Board of Surgery In-Service Training Examination. Data were analyzed from July 2019 to July 2022.

Exposure

Residents were asked, "Do you have a mentor who genuinely cares about you and your career?"

Main Outcomes and Measures

Resident characteristics associated with report of meaningful mentorship were evaluated with multivariable logistic regression. Associations of mentorship with education (clinical and operative autonomy) and wellness (career satisfaction, burnout, thoughts of attrition, suicidality) were examined using cluster-adjusted multivariable logistic regression controlling for resident and program factors. Residents' race and ethnicity were self-identified using US census categories (American Indian or Alaska Native, Asian, Black or African American, Native Hawaiian or Other Pacific Islander, and White), which were combined and dichotomized as non-Hispanic White vs non-White or Hispanic.

Results

A total of 6956 residents from 301 programs completed the survey (85.6% response rate); 6373 responded to all relevant questions (2572 [40.3%] female; 2539 [39.8%] non-White or Hispanic). Of these, 4256 (66.8%) reported meaningful mentorship. Non-White or Hispanic residents were less likely than non-Hispanic White residents to report meaningful mentorship (odds ratio [OR], 0.81, 95% CI, 0.71-0.91). Senior residents (postgraduate year 4/5) were more likely to report meaningful mentorship than interns (OR, 3.06; 95% CI, 2.59-3.62). Residents with meaningful mentorship were more likely to endorse operative autonomy (OR, 3.87; 95% CI, 3.35-4.46) and less likely to report burnout (OR, 0.52; 95% CI, 0.46-0.58), thoughts of attrition (OR, 0.42; 95% CI, 0.36-0.50), and suicidality (OR, 0.47; 95% CI, 0.37-0.60) compared with residents without meaningful mentorship.

Conclusions and Relevance

One-third of trainees reported lack of meaningful mentorship, particularly non-White or Hispanic trainees. Although education and wellness are multifactorial issues, mentorship was associated with improvement; thus, efforts to facilitate mentorship are needed, especially for minoritized residents.

ASO Practice Guidelines Series: Surgical Management of Gastrointestinal (Midgut) Neuroendocrine Neoplasms

Gastrointestinal midgut neuroendocrine neoplasms (NENs) are a heterogeneous group of uncommon malignancies. For well-differentiated NENs, known as neuroendocrine tumors (NETs), surgery is a cornerstone of management in localized and metastatic disease. Because of heterogeneous tumor behaviour, association with endocrine syndrome, and prognosis, the management of NETs must be individualized to all these factors in addition to the primary site. With the fast pace of advancement in the field, both for therapies and understanding of tumoral etiology and behaviour, it is important for surgical oncologists to remain updated on guidelines recommendations and suggested treatment pathways. Those guidelines provide important guidance for management of NETs but are largely based on expert opinions and interpretation of retrospective evidence. This article reviews highlights of most recent practice guidelines for midgut (gastric, duodenal, small intestinal, and appendiceal) NETs.

Can I Leave? Perspectives on Parental Leave and Parenthood in Medical Training Among Program Directors and Trainees in Oncologic Specialties

Purpose: Peak fertility commonly occurs during medical training, and delaying parenthood can complicate pregnancies. Trainee parental leave policies are varied and lack transparency. Research on the impacts of parenthood on trainee education is limited. Methods: A Qualtrics-based survey was distributed via e-mail/social media to program directors (PDs) within oncologic specialties with a request to forward a parallel survey to trainees. Questions assessed awareness of parental leave policies, supportiveness of parenthood, and impacts on trainee education. Statistical analyses included descriptive frequencies and bivariable comparisons by key groups. Results: A total of 195 PDs and 286 trainees responded. Twelve percent and 29% of PDs were unsure of maternity/paternity leave options, respectively. PDs felt they were more supportive of trainee parenthood than trainees perceived they were. Thirty-nine percent of nonparent trainees (NPTs) would have children already if not in medicine, and >80% of women trainees were concerned about declining fertility. Perceived impacts of parenthood on trainee overall education and academic productivity were more negative for women trainees when rated by PDs and NPTs; however, men/women parents self-reported equal impacts. Leave burden was perceived as higher for women trainees. Conclusions: A significant portion of PDs lack awareness of parental leave policies, highlighting needs for increased transparency. Trainees' perception of PD support for parenthood is less than PD self-reported support. Alongside significant rates of delayed parenthood and fertility concerns, this poses a problem for trainees seeking to start a family, particularly women who are perceived more negatively. Further work is needed to create a supportive culture for trainee parenthood.

Characterization of an oligometastatic state in patients with metastatic pancreatic adenocarcinoma undergoing systemic chemotherapy

PURPOSE/OBJECTIVES

Most patients with pancreatic adenocarcinoma (PDAC) will present with distant metastatic disease at diagnosis. We sought to identify clinical characteristics associated with prolonged overall survival (OS) in patients presenting with metastatic PDAC.

MATERIALS/METHODS

Patients presenting with metastatic PDAC that received treatment at our institution with FOLFIRINOX or gemcitabine-based chemotherapies between August 1, 2011 and September 1, 2017 were included in the study. Metastatic disease burden was comprehensively characterized radiologically via individual diagnostic imaging segmentation. Landmark analysis was performed at 18 months, and survival curves were estimated using the Kaplan-Meier method and compared between groups via the log-rank test. ECOG and Charlson Comorbidity Index (CCI) were calculated for all patients.

RESULTS

121 patients were included with a median age of 62 years (37-86), 40% were female, 25% had ECOG 0 at presentation. Of the 121 patients included, 33% (n = 41) were alive at 12 months and 25% (n = 31) were alive at 18 months. Landmark analysis demonstrated a significant difference between patients surviving <18 months and ≥18 months regarding the presence of lung only metastases (36% vs. 16%, p = 0.04), number of organs with metastases (≥2 vs. 1, p = 0.04), and disease volume (mean of 19.1 cc vs. 1.4 cc, p = 0.04). At Year 1, predictors for improved OS included ECOG status at diagnosis (ECOG 0 vs. ECOG 1, p = 0.04), metastatic disease volume at diagnosis (≤0.1 cc vs. >60 cc, p = 0.004), metastasis only in the liver (p = 0.04), and normalization of CA 19-9 (p < 0.001). At Year 2, the only predictor of improved OS was normalization of the CA 19-9 (p = 0.03). In those patients that normalized their CA 19-9, median overall survival was 16 months.

CONCLUSIONS

In this exploratory analysis normalization of CA-19-9 or volumetric metastatic disease burden less than 0.2 cc demonstrated a remarkable OS, similar to that of patients with non-metastatic disease. These metrics are useful for counseling patients and identifying cohorts that may be optimal for trials exploring metastatic and/or local tumor-directed interventions.

Biliary Adverse Events During Neoadjuvant Therapy for Pancreatic Cancer

OBJECTIVE

To describe a high-volume experience with biliary drainage before neoadjuvant therapy (NAT) for patients with operable pancreatic cancer (PC) and characterize the association between biliary adverse events (BAEs) and patient outcome.

BACKGROUND

Patients with PC presenting with biliary obstruction require durable decompression before NAT.

METHODS

Patients with operable PC and tumor-associated biliary obstruction were examined and grouped by the presence or absence of a BAE during NAT. The incidence, timing, and management of BAEs are described, and outcomes, including the completion of all treatment and overall survival (OS), were compared.

RESULTS

Of 426 patients who received pretreatment biliary decompression, 92 (22%) experienced at least 1 BAE during NAT, and 56 (13%) required repeat intervention on their biliary stent. The median duration of NAT was 161 days for all patients and was not different in the group that experienced BAEs. The median time from initial stent placement to BAE was 64 days. An interruption in the delivery of NAT (median 7 days) occurred in 25 (6%) of 426 patients. Among 426 patients, 290 (68%) completed all NAT, including surgery: 60 (65%) of 92 patients with BAE and 230 (69%) of 334 patients without BAE ( P =0.51). Among 290 patients who completed NAT and surgery, the median OS was 39 months, 26 months for the 60 patients with BAE, and 43 months for the 230 patients without BAE ( P =0.02).

CONCLUSIONS

During extended multimodal NAT for PC, 22% of patients experienced a BAE. Although BAEs were not associated with a significant interruption of treatment, patients who experienced a BAE had worse OS.

Severity of Prior Coronavirus Disease 2019 is Associated With Postoperative Outcomes After Major Inpatient Surgery

OBJECTIVE

To determine how the severity of prior history (Hx) of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection influences postoperative outcomes after major elective inpatient surgery.

BACKGROUND

Surgical guidelines instituted early in the coronavirus disease 2019 (COVID-19) pandemic recommended a delay in surgery of up to 8 weeks after an acute SARS-CoV-2 infection. This was based on the observation of elevated surgical risk after recovery from COVID-19 early in the pandemic. As the pandemic shifts to an endemic phase, it is unclear whether this association remains, especially for those recovering from asymptomatic or mildly symptomatic COVID-19.

METHODS

Utilizing the National COVID Cohort Collaborative, we assessed postoperative outcomes for adults with and without a Hx of COVID-19 who underwent major elective inpatient surgery between January 2020 and February 2023. COVID-19 severity and time from infection to surgery were each used as independent variables in multivariable logistic regression models.

RESULTS

This study included 387,030 patients, of whom 37,354 (9.7%) were diagnosed with preoperative COVID-19. Hx of COVID-19 was found to be an independent risk factor for adverse postoperative outcomes even after a 12-week delay for patients with moderate and severe SARS-CoV-2 infection. Patients with mild COVID-19 did not have an increased risk of adverse postoperative outcomes at any time point. Vaccination decreased the odds of respiratory failure.

CONCLUSIONS

Impact of COVID-19 on postoperative outcomes is dependent on the severity of illness, with only moderate and severe disease leading to a higher risk of adverse outcomes. Existing perioperative policies should be updated to include consideration of COVID-19 disease severity and vaccination status.

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.

Assessing the Complex General Surgical Oncology Pipeline: Trends in Race and Ethnicity Among US Medical Students, General Surgery Residents, and Complex General Surgical Oncology Trainees

BACKGROUND

Cancer incidence is expected to increase in coming decades, disproportionately so among minoritized communities. Racially and ethnically concordant care is essential to addressing disparities in cancer outcomes within at-risk groups. Here, we assess trends in racial and ethnic representation of medical students (MS), general surgery (GS) residents, and complex general surgical oncology (CGSO) fellows.

METHODS

This is a retrospective review of data from the American Association of Medical Colleges and the Accreditation Council of Medical Education (ACGME) from 2015 to 2020. Self-reported race and ethnicity was obtained for MS, GS, and CGSO trainees. Race and ethnicity proportions were compared with respective representation in the 2020 US Census. Mann-Kendall, Wilcoxon rank sum, and linear regression were used to assess trends, as appropriate.

RESULTS

A total of 316,448 MS applicants, 128,729 MS matriculants, 27,574 GS applicants, 46,927 active GS residents, 710 CGSO applicants, and 659 active CGSO fellows were included. With every progressive stage in training, there was a smaller proportion of URM active trainees than applicants. Further, URM, Hispanic/Latino, and Black/African American trainees were significantly underrepresented compared with 2020 Census data. While the proportion of White CGSO fellows increased over time (54.5-69.2%, p = 0.009), the proportion of Black/African American and Hispanic/Latino (URM) CGSO fellows did not significantly change over the study period, though URM representation was lower in 2020 as compared with 2015.

DISCUSSION

From 2015 to 2020, minority representation decreased at every advancing stage in surgical oncology training. Efforts to address barriers for URM applicants to CGSO fellowships are needed.

Automated machine learning (AutoML) can predict 90-day mortality after gastrectomy for cancer

Early postoperative mortality risk prediction is crucial for clinical management of gastric cancer. This study aims to predict 90-day mortality in gastric cancer patients undergoing gastrectomy using automated machine learning (AutoML), optimize models for preoperative prediction, and identify factors influential in prediction. National Cancer Database was used to identify stage I-III gastric cancer patients undergoing gastrectomy between 2004 and 2016. 26 features were used to train predictive models using H2O.ai AutoML. Performance on validation cohort was measured. In 39,108 patients, 90-day mortality rate was 8.8%. The highest performing model was an ensemble (AUC = 0.77); older age, nodal ratio, and length of inpatient stay (LOS) following surgery were most influential for prediction. Removing the latter two parameters decreased model performance (AUC 0.71). For optimizing models for preoperative use, models were developed to first predict node ratio or LOS, and these predicted values were inputted for 90-day mortality prediction (AUC of 0.73-0.74). AutoML performed well in predicting 90-day mortality in a larger cohort of gastric cancer patients that underwent gastrectomy. These models can be implemented preoperatively to inform prognostication and patient selection for surgery. Our study supports broader evaluation and application of AutoML to guide surgical oncologic care.

Clinical Impact and Accuracy of Shave Biopsy for Initial Diagnosis of Cutaneous Melanoma

INTRODUCTION

Effective treatment of malignant melanomas is dependent upon accurate histopathological staging of preoperative biopsy specimens. While narrow excision is the gold standard for melanoma diagnosis, superficial shave biopsies have become the preferred method by dermatologists but may transect the lesion and result in inaccurate Breslow thickness assessment. This is a retrospective cohort study evaluating an initial method of biopsy for diagnosis of cutaneous melanoma and indication for reoperation based on inaccurate initial T-staging.

METHODS

We retrospectively analyzed consecutive patients referred to the Medical College of Wisconsin, a tertiary cancer center, with a diagnosis of primary cutaneous melanoma. Adult patients seen between 2015 and 2018 were included. Fisher's exact test was used to assess the association between method of initial biopsy and need for unplanned reoperation.

RESULTS

Three hundred twenty three patients with cutaneous melanoma from the head and neck (H&N, n = 101, 31%), trunk (n = 90, 15%), upper extremity (n = 84, 26%), and lower extremity (n = 48, 28%) were analyzed. Median Breslow thickness was 0.54 mm (interquartile range = 0.65). Shave biopsy was the method of initial biopsy in 244 (76%), excision in 23 (7%), and punch biopsy in 56 (17%). Thirty nine (33%) shave biopsies had a positive deep margin, as did seven (23%) punch biopsies and 0 excisional biopsies. Residual melanoma at definitive excision was found in 131 (42.5%) of all surgical specimens: 95 (40.6%) shave biopsy patients, 32 (60.4%) punch biopsy patients, and four (19.0%) excision biopsy patients. Recommendations for excision margin or sentinel lymph node biopsy changed in 15 (6%) shave biopsy patients and five (9%) punch biopsy patients.

CONCLUSIONS

Shave biopsy is the most frequent method of diagnosis of cutaneous melanoma in the modern era. While shave and punch biopsies may underestimate true T-stage, there was no difference in need for reoperation due to T-upstaging based on initial biopsy type, supporting current diagnostic practices. Partial biopsies can thus be used to guide appropriate treatment and definitive wide local excision when adjusting for understaging.

Severity of Prior COVID-19 Infection is Associated with Postoperative Outcomes Following Major Inpatient Surgery

Objective

To determine the association between severity of prior history of SARS-CoV-2 infection and postoperative outcomes following major elective inpatient surgery.

Summary Background Data

Surgical guidelines instituted early in the COVID-19 pandemic recommended delay in surgery up to 8 weeks following an acute SARS-CoV-2 infection. Given that surgical delay can lead to worse medical outcomes, it is unclear if continuation of such stringent policies is necessary and beneficial for all patients, especially those recovering from asymptomatic or mildly symptomatic COVID-19.

Methods

Utilizing the National Covid Cohort Collaborative (N3C), we assessed postoperative outcomes for adults with and without a history of COVID-19 who underwent major elective inpatient surgery between January 2020 and February 2023. COVID-19 severity and time from SARS-CoV-2 infection to surgery were each used as independent variables in multivariable logistic regression models.

Results

This study included 387,030 patients, of which 37,354 (9.7%) had a diagnosis of preoperative COVID-19. History of COVID-19 was found to be an independent risk factor for adverse postoperative outcomes even after a 12-week delay for patients with moderate and severe SARS-CoV-2 infection. Patients with mild COVID-19 did not have an increased risk of adverse postoperative outcomes at any time point. Vaccination decreased the odds of mortality and other complications.

Conclusions

Impact of COVID-19 on postoperative outcomes is dependent on severity of illness, with only moderate and severe disease leading to higher risk of adverse outcomes. Existing wait time policies should be updated to include consideration of COVID-19 disease severity and vaccination status.

Patterns of Unnecessary Insurer Prior Authorization Denials in a Complex Surgical Oncology Practice

INTRODUCTION

Insurance prior authorization (PA) is a determination of need, required by a health insurer for an ordered test/procedure. If the test/procedure is denied, a peer-to-peer (P2P) discussion between ordering provider and payer is used to appeal the decision. The objective of this study was to measure the number and patterns of unnecessary PA denials.

METHODS

This was a retrospective review at a quaternary cancer center from October 2021 to March 2022. Included were all patients with outpatient imaging orders for surgical planning or surveillance of gastrointestinal, endocrine, or skin cancer. Primary outcome was unnecessary initial denial (UID) defined as an order that required preauthorization, was initially denied by the insurer, and subsequently overturned by P2P.

RESULTS

Nine hundred fifty seven orders were placed and 419 required PA (44%). Of tests requiring authorization, 55/419 (13.1%) were denied. Variability in the likelihood of initial denial was seen across insurers, ranging from 0% to 57%. Following P2P, 32/55 were overturned (58.2% UID). The insurers most likely to have a UID were Aetna (100%), Anthem (77.8%), and Cigna (50.0%). UID was most common for gastrointestinal (58.9%) and endocrine (58.3%) cancers. Average P2P was 33.5 min (interquartile range 28-40).

CONCLUSIONS

The majority of imaging studies initially denied were overturned after P2P. If all UIDs were eliminated, this would represent 108 less P2P discussions with an estimated time-savings of 60.3 h annually within a high-volume surgical oncology practice. Combined personnel costs to the health systems and stress on patients with cancer due to image-associated PAs and P2P appear hard to justify.

Outcomes of plastic surgical reconstruction in extremity and truncal soft tissue sarcoma: Results from the US Sarcoma Collaborative

BACKGROUND

This study aimed to define how utilization of plastic surgical reconstruction (PSR) affects perioperative outcomes, locoregional recurrence-free survival (LRRFS), and overall survival (OS) after radical resection of extremity and truncal soft tissue sarcoma (ETSTS). The secondary aim was to determine factors associated with PSR.

METHODS

Patients who underwent resection of ETSTS between 2000 and 2016 were identified from a multi-institutional database. PSR was defined as complex primary closure requiring a plastic surgeon, skin graft, or tissue-flap reconstruction. Outcomes included PSR utilization, postoperative complications, LRRFS, and OS.

RESULTS

Of 2750 distinct operations, 1060 (38.55%) involved PSR. Tissue-flaps (854, 80.57%) were most commonly utilized. PSR was associated with a higher proportion of R0 resections (83.38% vs. 74.42%, p < 0.001). Tissue-flap PSR was associated with local wound complications (odds ratio: 1.81, confidence interval: 1.21-2.72, p = 0.004). Neither PSR nor postoperative complications were independently associated with LRRFS or OS. High-grade tumors (1.60, 1.13-2.26, p = 0.008) and neoadjuvant radiation (1.66, 1.20-2.30, p = 0.002) were associated with the need for PSR.

CONCLUSION

Patients with ETSTS undergoing resection with PSR experienced acceptable rates of complications and a higher rate of negative margins, which were associated with improved LRRFS and OS. High tumor grade and neoadjuvant radiation were associated with requirement of PSR.

CA19-9 Response to First-Line Neoadjuvant FOLFIRINOX and Second-Line Gemcitabine/Nab-Paclitaxel for Patients with Operable Pancreatic Cancer

BACKGROUND

Response to second-line (2L) neoadjuvant therapy for operable pancreatic cancer (PC) is understudied. This study examined carbohydrate antigen 19-9 (CA19-9) response to first-line (1L) and 2L chemotherapy.

METHODS

The study identified patients with operable PC and elevated CA19-9 (≥ 35 U/mL with total bilirubin < 2 mg/dL) who received 1L FOLFIRINOX (FFX). The patients were restaged after 2 months and based on response, received additional FFX or gemcitabine/nab-paclitaxel (GnP) as part of total neoadjuvant therapy. Response was defined as a decrease in tumor size on computed tomography (CT) imaging or a decline in CA19-9 of 50% or more and preserved performance status.

RESULTS

For operable PC with an elevated CA19-9, 108 patients received 1L FFX. After 2 months of chemotherapy, the decision was made to continue FFX (FFX ≥ FFX) for 76 (70%) of the 108 patients and switch to GnP (FFX ≥ GnP)) for 32 (30%) of the patients. Of the 32 FFX ≥ GnP patients, 27 had no evidence of radiographic or biochemical (CA19-9) response to 1L FFX. Of these 27 patients, 26 (96%) demonstrated a response to 2L GnP. After 4 months of chemotherapy, 62 (82%) of the 76 FFX ≥ FFX patients had a CA19-9 response compared with 31 (97%) of the 32 FFX ≥ GnP patients (p = 0.04).

CONCLUSIONS

Lack of biochemical response to 2 months of 1L FFX may identify a subgroup of patients with a very high rate of response to 2L GnP, emphasizing the importance of assessing treatment response at 2-month intervals.

Palliative Cytoreductive Surgery With or Without Hyperthermic Intraperitoneal Chemotherapy for Peritoneal Carcinomatosis: Is It Safe and Effective?

INTRODUCTION

Palliation is a controversial indication for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Patients with peritoneal carcinomatosis (PC) are living longer, and the roles of palliative CRS and HIPEC are increasingly challenged. The purpose of this study is to evaluate indications, morbidity, and symptom improvement from CRS/HIPEC in advanced PC.

METHODS

A retrospective review of patients undergoing CRS and/or HIPEC with a palliative intent at a single institution from February 2008 to February 2018 was performed. Main end points included symptom improvement, symptom-free interval, and overall survival.

RESULTS

Two hundred and seventy seven patients were referred for CRS/HIPEC during the study period and 17 underwent 20 palliative procedures. Appendiceal (n = 6) and colorectal cancers (n = 6) were the most common malignancies. Ascites (n = 8) and bowel obstruction (n = 8) were the most common indications for intervention. The postoperative complication rate was 50% and major complication rate was 20%. Partial symptom improvement or resolution of symptoms was achieved in 18 (90%) cases. A durable symptom control at 90 d was achieved in 13 (65%) cases. The median time to symptom recurrence was 5.1 mo (interquartile range: 2-11.4), and the median overall survival was 11.6 mo (interquartile range: 3.8-28.5).

CONCLUSIONS

Palliative CRS and/or HIPEC achieve symptom improvement in patients with advanced PC. Risk assessment and expected time to recovery from surgery remain paramount for patient selection.

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.

Disparities in Creating a Diverse Surgical Oncology Physician Workforce: Just a Leaky Pipeline?

Demographic shifts in the Unites States population highlight the growing need for a diverse physician workforce to care for communities of color and to eliminate existing disparities in cancer care and outcomes for these potentially vulnerable patients. The current surgical oncology workforce lacks adequate racial and ethnic representation, and the pool of medical students and surgical trainees who are underrepresented in medicine (URM) is scant. This review critically evaluates data, summarizes challenges in the recruitment and retention of URM surgeons to surgical oncology, and provides strategies to address these workforce deficits.

A novel preoperative risk score to guide patient selection for resection of soft tissue sarcoma lung metastases: An analysis from the United States Sarcoma Collaborative

BACKGROUND

Surgical resection for sarcoma lung metastases has been associated with improved overall survival (OS).

METHODS

Patients who underwent curative-intent resection of sarcoma lung metastases (2000-2016) were identified from the US Sarcoma Collaborative. Patients with extrapulmonary metastatic disease or R2 resections of primary tumor or metastases were excluded. Primary endpoint was OS.

RESULTS

Three hundred and fifty-two patients met inclusion criteria. Location of primary tumor was truncal/extremity in 85% (n = 270) and retroperitoneal in 15% (n = 49). Forty-nine percent (n = 171) of patients had solitary and 51% (n = 180) had multiple lung metastasis. Median OS was 49 months; 5-year OS 42%. Age ≥55 (HR 1.77), retroperitoneal primary (HR 1.67), R1 resection of primary (HR 1.72), and multiple (≥2) lung metastases (HR 1.77) were associated with decreased OS(all p < 0.05). Assigning one point for each factor, we developed a risk score from 0 to 4. Patients were then divided into two risk groups: low (0-1 factor) and high (2-4 factors). The low-risk group (n = 159) had significantly better 5-year OS compared to the high-risk group (n = 108) (51% vs. 16%, p < 0.001).

CONCLUSION

We identified four characteristics that in aggregate portend a worse OS and created a novel prognostic risk score for patients with sarcoma lung metastases. Given that patients in the high-risk group have a projected OS of <20% at 5 years, this risk score, after external validation, will be an important tool to aid in preoperative counseling and consideration for multimodal therapy.

Breast Cancer Risk and Screening in Transgender Persons: A Call for Inclusive Care

The Society of Surgical Oncology is committed to reducing health disparities adversely affecting sexual and gender minorities. Transgender persons represent a socially disadvantaged group who frequently experience discrimination and receive disparate care, resulting in suboptimal cancer outcomes. The rate of breast cancer development in transgender individuals differs from rates observed in their cisgender counterparts, however there is little evidence to quantify these differences and guide evidence-based screening and prevention. There is no consensus for breast cancer screening guidelines in transgender patients. In this review, we discuss barriers to equitable breast cancer care, risk factors for breast cancer development, and existing data to support breast cancer screening in transgender men and women.

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.

Detection of germline variants using expanded multigene panels in patients with localized pancreatic cancer

BACKGROUND

Current guidelines recommend genetic testing for all patients with pancreatic cancer (PC).

METHODS

Patients with localized PC who received neoadjuvant therapy between 2009 and 2018 were identified. Genetic consultation (including personal and family history of cancer), genetic testing, and variant data were abstracted.

RESULTS

Of 510 patients identified, 163 (32%) underwent genetic counseling and genetic testing was performed in 127 (25%). Patients who underwent genetic testing were younger (median age: 63 vs. 67, p = 0.01). Multi-gene testing was performed in 114 (90%) of 127 patients, targeted gene testing was performed in 8 (6%), and not specified in 5 (4%). Of 127 patients who underwent genetic testing, 20 (16%) had pathogenic (P)/likely pathogenic (LP) variants, observed in ATM (n = 7/105,7%), CHEK2 (n = 3/98, 3%), BRCA1 (n = 2/117, 2%), BRCA2 (n = 2/122, 2%), PALB2 (n = 1/115, 1%), MUTYH (n = 1/98, 1%), CDKN2A (n = 1/94, 1%), STK11 (n = 1/97, 1%), NBN (n = 1/98, 1%), and MSH6 (n = 1/97, 1%). Of 20 patients with either a P/LP variant, nine (45%) had a prior cancer, three (15%) had a first-degree relative with PC, and six (30%) had an any-degree relative with PC.

CONCLUSION

Pathogenic/likely pathogenic variants were identified in 16% of patients who underwent genetic testing, 60% of which occurred in the homologous recombination pathway.

Renal Function After Retroperitoneal Sarcoma Resection with Nephrectomy: A Matched Analysis of the United States Sarcoma Collaborative Database

BACKGROUND

Nephrectomy often is required during en bloc resection of a retroperitoneal sarcoma (RPS) to achieve an R0 or R1 resection. The impact of nephrectomy on postoperative renal function in this patient population, who also may benefit from subsequent nephrotoxic systemic therapy, is not well described.

METHODS

The United States Sarcoma Collaborative (USSC) database was queried for patients undergoing RPS resection between 2000 and 2016. Patients with missing pre- or postoperative measures of renal function were excluded. A matched cohort was created using coarsened exact matching. Weighted logistic regression was used to control further for differences between the nephrectomy and non-nephrectomy cohorts. The primary outcomes were postoperative acute kidney injury (AKI), acute renal failure (ARF), and dialysis.

RESULTS

The initial cohort consisted of 858 patients, 3 (0.3%) of whom required postoperative dialysis. The matched cohort consisted of 411 patients, 108 (26%) of whom underwent nephrectomy. The patients who underwent nephrectomy had higher rates of postoperative AKI (14.8% vs 4.3%; p < 0.01) and ARF (4.6% vs 1.3%; p = 0.04), but no patients required dialysis postoperatively. Logistic regression modeling showed that the risk of AKI (odds ratio [OR], 5.16; p < 0.01) and ARF (OR 5.04; p < 0.01) after nephrectomy persisted despite controlling for age and preoperative renal function.

CONCLUSIONS

Nephrectomy is associated with an increased risk of postoperative AKI and ARF after RPS resection. This study was unable to statistically assess the impact of nephrectomy on postoperative dialysis, but the risk of postoperative dialysis is 0.5% or less regardless of nephrectomy status.

Total Neoadjuvant Therapy for Operable Pancreatic Cancer

BACKGROUND

Overall survival (OS) for operable pancreatic cancer (PC) is optimized when 4-6 months of nonsurgical therapy is combined with pancreatectomy. Because surgery renders the delivery of postoperative therapy uncertain, total neoadjuvant therapy (TNT) is gaining popularity.

METHODS

We performed a retrospective cohort study of patients with operable PC and compared TNT with shorter course neoadjuvant therapy (SNT). Primary outcomes of interest included completion of neoadjuvant therapy (NT) and resection of the primary tumor, receipt of 5 months of nonsurgical therapy, and median OS.

RESULTS

We reviewed 541 consecutive patients from 2009 to 2019 including 226 (42%) with resectable PC and 315 (58%) with borderline resectable (BLR) PC. The median age was 66 years (IQR [59, 72]), and 260 (48%) patients were female. TNT was administered to 89 (16%) patients and SNT was administered to 452 (84%). Both groups were equally likely to complete intended NT and surgery (p = 0.90). Patients who received TNT and surgical resection were more likely to have a complete pathologic response (8% vs 4%, p < 0.01) and were more likely to receive at least 5 months of nonsurgical therapy (67% vs 45%, p < 0.01). The median OS was 26 months [IQR (15, 57)]; not reached among patients treated with TNT, and 25 months [IQR (15, 56)] among patients treated with SNT (p = 0.19).

CONCLUSIONS

TNT ensures the delivery of intended systemic therapy prior to a complicated operation without decreasing the chance of successful surgery; a window of operability was not lost. Patients who can tolerate SNT will likely benefit from TNT.

Retroperitoneal sarcoma perioperative risk stratification: A United States Sarcoma Collaborative evaluation of the ACS-NSQIP risk calculator

BACKGROUND

The ACS-NSQIP risk calculator predicts perioperative risk. This study tested the calculator's ability to predict risk for outcomes following retroperitoneal sarcoma (RPS) resection.

METHODS

The United States Sarcoma Collaborative database was queried for adults who underwent RPS resection. Estimated risk for outcomes was calculated twice in the risk calculator, once using sarcoma-specific CPT codes and once using codes indicative of most comorbid organ resection (eg nephrectomy). ROC curves were generated, with area under the curve (AUC) and Brier scores reported to assess discrimination and calibration. An AUC < 0.6 was considered ineffective discrimination. A negative ▲ Brier indicated improved performance relative to baseline outcome rates.

RESULTS

In total, 482 patients were identified with a 42.3% 90-day complication rate. Discrimination was poor for all outcomes except "all complications" and "renal failure." Baseline outcome rates were better predictors than calculator estimates except for "discharge to nursing or rehab facility" and "renal failure." Replacing sarcoma-specific CPT codes with resection-specific codes did not improve performance.

CONCLUSION

The ACS-NSQIP risk calculator poorly predicted outcomes following RPS resection. Changing sarcoma-specific CPT to resection-specific codes did not improve performance. Comorbidities in the calculator may not effectively capture perioperative risk. Future work should evaluate a sarcoma-specific calculator.

High neutrophil-lymphocyte ratio is not independently associated with worse survival or recurrence in patients with extremity soft tissue sarcoma

BACKGROUND

Soft tissue sarcomas are a heterogenous group of neoplasms without well-validated biomarkers. Cancer-related inflammation is a known driver of tumor growth and progression. Recent studies have implicated a high circulating neutrophil-lymphocyte ratio as a surrogate marker for the inflammatory tumor microenvironment and a poor prognosticator in multiple solid tumors, including colorectal and pancreatic cancers. The impact of circulating neutrophil-lymphocyte ratio in soft tissue sarcomas has yet to be elucidated.

METHODS

We performed a retrospective analysis of patients undergoing curative resection for primary or recurrent extremity soft tissue sarcomas at academic centers within the US Sarcoma Collaborative. Neutrophil-lymphocyte ratio was calculated retrospectively in treatment-naïve patients using blood counts at or near diagnosis.

RESULTS

A high neutrophil-lymphocyte ratio (≥4.5) was associated with worse survival on univariable analysis in patients with extremity soft tissue sarcomas (hazard ratio 2.07; 95% confidence interval, 1.54-2.8; P < .001). On multivariable analysis, increasing age (hazard ratio 1.03; 95% confidence interval, 1.02-1.04; P < .001), American Joint Committee on Cancer T3 (hazard ratio 1.89; 95% confidence interval, 1.16-3.09; P = .011), American Joint Committee on Cancer T4 (hazard ratio 2.36; 95% confidence interval, 1.42-3.92; P = .001), high tumor grade (hazard ratio 4.56; 95% confidence interval, 2.2-9.45; P < .001), and radiotherapy (hazard ratio 0.58; 95% confidence interval, 0.41-0.82; P = .002) were independently predictive of overall survival, but a high neutrophil-lymphocyte ratio was not predictive of survival (hazard ratio 1.26; 95% confidence interval, 0.87-1.82; P = .22).

CONCLUSION

Tumor inflammation as measured by high pretreatment neutrophil-lymphocyte ratio was not independently associated with overall survival in patients undergoing resection for extremity soft tissue sarcomas.

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.

Institutional variation in recovery after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: An opportunity for enhanced recovery pathways

BACKGROUND

Variations in care have been demonstrated both within and among institutions in many clinical settings. By standardizing perioperative practices, Enhanced Recovery After Surgery (ERAS) pathways reduce variation in perioperative care. We sought to characterize the variation in cytoreductive surgery (CRS)/heated intraperitoneal chemotherapy (HIPEC) perioperative practices among experienced US medical centers.

METHODS

Data from the US HIPEC Collaborative represents a retrospective multi-institutional cohort study of CRS and CRS/HIPEC procedures performed from 12 major academic institutions. Patient characteristics and perioperative practices were reported and compared. Institutional variation was analyzed using hierarchical mixed-effects linear (continuous outcomes) or logistic (binary outcomes) regression models.

RESULTS

A total of 2372 operations were included. CRS/HIPEC was performed most commonly for appendiceal histologies (64.2%). The rate of complications (overall 56.3%, range: 31.8-70.9) and readmissions (overall 20.6%, range: 8.9-33.3) varied by institution (P < .001). Institution-level variation in perioperative practice patterns existed among measured ERAS pathway process/outcomes (P < .001). The percentages of variation with each process/outcome measure attributable solely to institutional practices ranged from 0.6% to 66.6%.

CONCLUSIONS

Significant variation exists in the perioperative care of patients undergoing CRS/HIPEC at major US academic institutions. These findings provide a strong rationale for the investigation of best practices in CRS/HIPEC patients.

Pancreatic neuroendocrine neoplasms: current state and ongoing controversies on terminology, classification and prognostication

Significant improvements have taken place in our understanding of classification neuroendocrine neoplasms of the pancreas in the past decade. These are now regarded in three entirely separate categories: (I) neuroendocrine tumors (PanNETs) are by definition well differentiated, the pancreatic counterpart of carcinoids; (II) neuroendocrine carcinomas, which are poorly differentiated (PDNEC), the pancreatic examples of small cell carcinomas or large cell neuroendocrine carcinomas; (III) other neoplasms that have neuroendocrine differentiation or a distinct neuroendocrine component. PanNETs are by far the most common. They are now regarded as malignancies (albeit often curable when low grade and low stage) with the exception of minute incidental proliferations (tumorlets, or dysplastic-like changes) seen in the setting of some syndromes like MEN. PanNETs are staged based on their size, and for small T1 tumors, watchful waiting is now being considered, although these tumors are also known to show about 10% metastatic rate and/or progression, creating concerns about this approach. PanNETs are graded into 3, based on the proliferative activity, mostly based on the Ki-67 index, and also partly mitotic activity, although the latter seldom if ever is the determinant of the final grade. Neuroendocrine neoplasms with well differentiated morphology but Ki-67 >20% are now regarded as PanNET Grade 3 (G3); they have been shown to have a prognosis significantly worse than lesser grade PanNETs but still incomparably better than frank PDNECs, the latter typically has Ki-67 >50% (often much higher) and require platinum-based chemotherapy. There are also cases that are ambiguous between PanNET-G3 and PDNEC, and very rarely transformation of the former to the latter appears to occur. For low grade (G1/G2) PanNETs, more refined criteria to further prognosticate this group are needed. Morphologic variants being recognized may bring new perspectives to this group.

Value of Pretreatment 18F-fluorodeoxyglucose Positron Emission Tomography in Patients With Localized Pancreatic Cancer Treated With Neoadjuvant Therapy

Background:¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) imaging is not routine in patients with localized pancreatic cancer (PC). We evaluated the prognostic value of PET/CT in patients who received neoadjuvant therapy.

Methods: Patients with localized PC underwent pretreatment PET/CT with or without posttreatment (preop) PET/CT. Maximum standardized uptake values (SUV) were classified as high or low based on a cut point of 7.5 at diagnosis (SUV_dx) and 3.5 after neoadjuvant therapy (preoperative; SUV_preop). Preop carbohydrate antigen 19-9 (CA19-9) was classified as normal ( ≤ 35 U/mL) or elevated.

Results: Pretreatment PET/CT imaging was performed on 201 consecutive patients; SUV_dx was high in 98 (49%) and low in 103 (51%). Preop PET/CT was available in 104 (52%) of the 201 patients; SUV_preop was high in 60 (58%) and low in 44 (42%). Following neoadjuvant therapy, preop CA19-9 was normal in 90 (45%) patients and elevated in 111 (55%). Median overall survival (OS) of all patients was 27 months; 33 months for the 103 patients with a low SUV_dx and 22 months for the 98 patients with a high SUV_dx (p = 0.03). Median OS for patients with low SUV_dx/normal preop CA19-9, high SUV_dx/normal preop CA19-9, low SUV_dx/elevated preop CA19-9, and high SUV_dx/elevated preop CA19-9 were 66, 34, 23, and 17 months, respectively (p < 0.0001). OS was 44 months for the 148 (74%) patients who completed all intended neoadjuvant therapy and surgery and 13 months for the 53 (26%) who did not undergo surgery (p < 0.001).

Conclusion: Pretreatment PET/CT avidity and preop CA19-9 are clinically significant prognostic markers in patients with PC.

Impact of Neoadjuvant Chemoradiation on Pathologic Response in Patients With Localized Pancreatic Cancer

Introduction/Background: Multimodal neoadjuvant therapy has resulted in increased rates of histologic response in pancreatic tumors and adjacent lymph nodes. The biologic significance of the collective response in the primary tumor and lymph nodes is not understood.

Methods: Patients with localized PC who received neoadjuvant therapy and surgery with histologic assessment of the primary tumor and local-regional lymph nodes were included. Histopathologic response was classified using the modified Ryan score as follows: no viable cancer cells (CR), rare groups of cancer cells (nCR), residual cancer with evident tumor regression (PR), and extensive residual cancer with no evident tumor regression (NR). Nodal status was defined by number of lymph nodes (LN) with tumor metastases: N0 (0 LN), N1 (1–3), N2 (≥4).

Results: Of 341 patients with localized PC who received neoadjuvant therapy and surgery, 107 (31%) received chemoradiation alone, 44 (13%) received chemotherapy alone, and 190 (56%) received chemotherapy and chemoradiation. Histopathologic response consisted of 15 (4%) CRs, 59 (17%) nCRs, 188 (55%) PRs, and 79 (23%) NRs. Patients who received chemotherapy alone had the worst responses (n = 21 for NR, 48%) as compared to patients who received chemoradiation alone (n = 25 for NR, 24%) or patients who received both therapies (n = 33 for NR, 17%) (Table 1; p = 0.001). Median overall survival for all 341 patients was 39 months; OS by histopathologic subtype was not reached (CR), 49 months (nCR), 38 months (PR), and 34 months (NR), respectively (p = 0.004). Of the 341 patients, 208 (61%) had N0 disease, 97 (28%) had N1 disease, and 36 (11%) had N2 disease. In an adjusted hazards model, modified Ryan score of PR or NR (HR: 1.71; 95% CI: 1.15–2.54; p = 0.008) and N1 (HR: 1.42; 95% CI: 1.1.02–2.01; p = 0.04), or N2 disease (HR: 2.54, 95% CI: 1.64–3.93; p < 0.001) were associated with increased risk of death.

Conclusions: Neoadjuvant chemotherapy alone is associated with lower rates of pathologic response. Patients with CR or nCR have a significantly improved OS as compared to patients with PR or NR. Nodal status is the most important pathologic prognostic factor. Neoadjuvant chemoradiation may be an important driver of pathologic response.

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.

Using a Novel Diagnostic Nomogram to Differentiate Malignant from Benign Parathyroid Neoplasms

We sought to develop an immunohistochemical (IHC) tool to support the diagnosis of parathyroid carcinoma (PC) and help differentiate it from atypical parathyroid neoplasms (atypical) and benign adenomas. Distinguishing PC from benign parathyroid neoplasms can be challenging. Many cases of PC are histopathologically borderline for definitive malignancy. Recently, individual IHC biomarkers have been evaluated to aid in discrimination between parathyroid neoplasms. PC, atypical parathyroid neoplasms, and parathyroid adenomas treated at our institution from 1997 to 2014 were studied retrospectively. IHC analysis was performed to evaluate parafibromin, retinoblastoma (RB), protein gene product 9.5 (PGP9.5), Ki67, galectin-3, and E-cadherin expression. Receiver operating characteristic (ROC) analysis and multivariable logistic regression model for combinations of biomarkers were evaluated to classify patients as PC or atypical/adenoma. A diagnostic nomogram using 5 biomarkers was created for PC. Sixty-three patients were evaluated. The percent staining of parafibromin (p < 0.0001), RB (p = 0.04), Ki67 (p = 0.02), PGP9.5 (p = 0.04), and Galectin-3 (p = 0.01) differed significantly in the three diagnostic groups. ROC analysis demonstrated that parafibromin had the best performance in discriminating PC from atypical/adenoma; area under the curve (AUC) was 81% (cutoff, 92.5%; sensitivity rate, 64%; specificity rate, 87%). We created a diagnostic nomogram using a combination of biomarkers; AUC was 84.9% (95% confidence interval, 73.4-96.4%). The optimism-adjusted AUC for this model was 80.5% (mean absolute error, 0.043). A diagnostic nomogram utilizing an immunoexpression, a combination of immunohistochemical biomarkers, can be used to help differentiate PC from other parathyroid neoplasms, thus potentially improving diagnostic classification.

Role of radiation therapy for retroperitoneal sarcomas: An eight-institution study from the US Sarcoma Collaborative

BACKGROUND

The use of radiation therapy in the treatment of retroperitoneal sarcomas has increased in recent years. Its impact on survival and recurrence is unclear.

METHODS

A retrospective propensity score matched (PSM) analysis of patients with primary retroperitoneal soft tissue sarcomas, who underwent resection from 2000 to 2016 at eight institutions of the US Sarcoma Collaborative, was performed. Patients with metastatic disease, desmoid tumors, and palliative resections were excluded.

RESULTS

Total 425 patients were included, 56 in the neoadjuvant radiation group (neo-RT), 75 in the adjuvant radiation group (adj-RT), and 294 in the no radiotherapy group (no-RT). Median age was 59.5 years, 186 (43.8%) were male with a median follow up of 31.4 months. R0 and R1 resection was achieved in 253 (61.1%) and 143 (34.5%), respectively. Overall 1:1 match of 46 adj-RT and 59 neo-RT patients was performed using histology, sex, age, race, functional status, tumor size, grade, resection status, and chemotherapy. Unadjusted recurrence-free survival (RFS) was 35.9 months (no-RT) vs 33.5 months (neo-RT) and 27.2 months (adj-RT), P = .43 and P = .84, respectively. In the PSM, RFS was 17.6 months (no-RT) vs 33.9 months (neo-RT), P = .28 and 19 months (no-RT) vs 27.2 months (adj-RT), P = .1.

CONCLUSIONS

Use of radiotherapy, both in adjuvent or neoadjuvent setting, was not associated with improved survival or reduced recurrence rate.