General Surgery Resident Participation in a Mandatory Wellness Program: Six Years Later.

INTRODUCTION: Following the approval of a resident-created physician wellness program in 2016, an initial survey demonstrated majority support for the implementation of a mandatory curriculum. The purpose of this study is to survey surgical residents about the wellness curriculum six years after implementation and re-evaluate preference for mandatory participation. METHODS: In 2016, the CORE7 Wellness Program didactic sessions were integrated into the general surgery resident education curriculum. A comparison between 2016 and 2022 resident survey results was done to examine overall approval and resident experience. RESULTS: A total of 25 general surgery residents responded to the 2022 survey which equaled to a response rate of 67.5% compared to a response rate of 87.1% in 2016. Similar to the results in 2016, there was unanimous support (100%, n = 25) in favor of the ongoing development of a general surgery wellness program. The majority of residents (88% versus 85.2% in 2016) preferred quarterly "wellness half-days" remain a mandatory component of the program. In 2016, most of the residents (50%) stated that the reason for mandatory preference for wellness half-days was ease of explanation to faculty. In 2022, the reason changed to a combination of reasons with most residents (59%) selecting ease of explanation to attendings, feeling too guilty otherwise to leave the shift, and forcing the resident to think about self-care. Complaints about taking a wellness half-day from other team members increased from 29% in 2016 to 48% in 2022. CONCLUSIONS: Six years after implementation, there is unanimous support for the mandatory components of a general surgery residency wellness curriculum. Increased perceived complaints from faculty and staff about resident wellness present an opportunity for improvement.

Factors Associated With Upstaging of Melanoma Thickness on Final Excision.

INTRODUCTION: The incidence and risk factors associated with upstaging from initial biopsy to definitive excision in cutaneous melanoma have not been established. The aim of this study was to determine the incidence of tumor stage upstaging and associated risk factors using the National Cancer Database. METHODS: A retrospective study of the National Cancer Database between 2012 and 2016 was performed. The cohort of patients undergoing excision of melanoma with available data comprised 133,592 patients. Differences in characteristics for upstaging were determined using Wilcox rank-sum, chi-square, or Fisher's exact tests. Multivariable analysis was performed using logistic regression to determine factors associated with upstaging. RESULTS: Incidence of upstaging was 5.2%. Upstaged patients were older, male, of non-White race, and of lower education level (P < 0.001). Lesions of the head/neck and lower extremity had increased incidence of upstaging compared to the trunk (P < 0.001). Nodular and acral lentiginous melanoma was associated with higher incidence of upstaging compared to superficial spreading melanoma (P < 0.001). Patients with lymphovascular invasion had increased risk of upstaging (P < 0.001). CONCLUSIONS: Upstaging of melanoma is infrequent but is significantly more prevalent in non-White patients and those with lower educational status. Provider and patient education should include the higher risk of upstaging in these groups and the possible need for further surgical intervention, such as re-excision of margins and sentinel lymph node biopsy.

Does Neoadjuvant Radiation Therapy Contribute to the Incidence of Pulmonary Complications Following Esophagectomy for Malignant Neoplasm?

BACKGROUND: Post-operative pulmonary complications (POPC) are common in patients undergoing esophagectomy and neoadjuvant radiotherapy may exacerbate POPC. This study assessed whether neoadjuvant radiation increases the incidence of POPC in patients undergoing esophagectomy for malignancy. METHODS: The American College of Surgeons-National Surgical Quality Improvement Program database files from 2016 to 2018 were queried for patients undergoing esophagectomy for malignancy. Inverse probability treatment weighting (IPTW) was used to create balanced cohorts in which the control group received neoadjuvant chemotherapy (nCT) and the treatment cohort received neoadjuvant chemoradiotherapy (nCRT). A subset analysis was performed on patients with pre-existing pulmonary disease (PEPD). Primary outcomes were POPC and 30-day mortality. RESULTS: The all-patient analysis did not demonstrate a consistent association between neoadjuvant radiation and POPC. However, in patients with PEPD, POPC occurred more often in the nCRT cohort. Comparing nCRT to nCT and after IPTW adjustment for confounders, there was higher odds of pneumonia (aOR = 3.0, P = .002), unplanned intubation (aOR = 2.0, P = .03), and extended mechanical ventilation (aOR = 3.6, P = .002). DISCUSSION: In esophageal cancer patients with PEPD that undergo nCRT vs nCT prior to esophagectomy, the greater risk of POPCs must be weighed against the potential for improved oncologic outcomes.

Robotic pancreatoduodenectomy: trends in technique and training challenges.

BACKGROUND: More complex cases are being performed robotically. This study aims to characterize trends in robotic pancreatoduodenectomy (RPD) over time and assess opportunities for advanced trainees. METHODS: Using the ACS-NSQIP database from 2014 to 2019, PD cases were characterized by operative approach (open-OPN, laparoscopic-LAP, robotic-ROB). Proficiency and postoperative outcomes were described by approach over time. RESULTS: 24,268 PDs were identified, with the ROB approach increasing from 2.8% to 7.5%. Unplanned conversion increased over time for LAP (27.7-39.0%, p = 0.003) but was unchanged for ROB cases (14.8-14.7%, p = 0.257). Morbidity increased for OPN PD (35.5-36.8%, p = 0.041) and decreased for ROB PD (38.7-30.3%, p = 0.010). Mean LOS was lower in ROB than LAP/OPN (9.5 vs. 10.9 vs. 10.9 days, p < 0.00001). Approximately, 100 AHPBA, SSO, and ASTS fellows are being trained each year in North America; however, only about 5 RPDs are available per trainee per year which is far below that recommended to achieve proficiency. CONCLUSION: Over a 6-year period, a significant increase was observed in the use of RPD without a concomitant increase in conversion rates. RPD was associated with decreased morbidity and length of stay. Despite this shift, the number of cases being performed is not adequate for all fellows to achieve proficiency before graduation.

Pancreatoduodenectomy: the Metabolic Syndrome is Associated with Preventable Morbidity and Mortality.

BACKGROUND: Patients with metabolic syndrome (MS) may have increased perioperative morbidity and mortality. The aim of this analysis was to investigate the association of MS with mortality, serious morbidity, and pancreatectomy-specific outcomes in patients undergoing pancreatoduodenectomy (PD). METHODS: Patients with MS who underwent PD were selected from the 2014-2018 ACS-NSQIP pancreatectomy-specific database. MS was defined as obesity (BMI ≥ 30 kg/m2), diabetes, and hypertension. Demographics and outcomes were compared by χ2 and Mann-Whitney tests, and adjusted odds ratios from multivariable logistic regression assessed the association between MS and primary outcomes. RESULTS: Of 19,054 patients who underwent PD, 7.3% (n = 1388) had MS. On univariable analysis, patients with MS had significantly worse outcomes (p < 0.05): 30-day mortality (3% vs 1.8%), serious morbidity (26% vs 23%), re-intubation (4.9% vs 3.5%), pulmonary embolism (2.0% vs 1.1%), acute renal failure (1.5% vs 0.9%), cardiac arrest (1.9% vs 1.0%), and delayed gastric emptying (18% vs 16.5%). On multivariable analysis, 30-day mortality was significantly increased in patients with MS (aOR: 1.53, p < 0.01). CONCLUSION: Metabolic syndrome is associated with increased morbidity and mortality in patients undergoing pancreatoduodenectomy. The association with mortality is a novel observation. Perioperative strategies aimed at reduction and/or mitigation of cardiac, pulmonary, thrombotic, and renal complications should be employed in this population given their increased risk.

Expression of PD-L1 in Patients With Malignant Peritoneal Mesothelioma: A Pilot Study.

INTRODUCTION: Frequency of PD-L1 expression and the role of immunotherapy in malignant peritoneal mesothelioma (MPM) have not been well characterized. The purpose of this study was to determine PD-L1 expression in patients with MPM and perform an exploratory analysis for associations between PD-L1 and its biological behavior in MPM. METHODS: Tumor samples were collected from patients undergoing surgical interventions between January 2018 and June 2020. Specimens were stained with anti-PD-L1 antibodies (Dako 22c3) and positivity was determined by tumor proportion score (TPS) or combined positive score (CPS) being ≥1%. RESULTS: Twenty one samples were obtained from 21 patients. Sixteen of 21 (76%) samples were CPS positive and 9 of 21 (43%) were TPS positive. Three samples had more aggressive biphasic/sarcomatoid histology and a high CPS and TPS (CPS: 3, 75, 95%; TPS: 2, 60, 90%). On an exploratory analysis, as the CPS or TPS threshold increased, there was a trend towards worse survival. CONCLUSIONS: MPM has a high frequency of PD-L1 expression, which may be associated with more aggressive tumor biology. These data provide the foundation for continued evaluation of checkpoint inhibition in patients with MPM.

Effect of the COVID-19 pandemic on surgical oncology practice-Results of an SSO survey.

BACKGROUND AND OBJECTIVES: The COVID-19 pandemic significantly affected healthcare delivery, shifting focus away from nonurgent care. The aim of this study was to examine the impact of the pandemic on the practice of surgical oncology. METHODS: A web-based survey of questions about changes in practice during the COVID-19 pandemic was approved by the Society of Surgical Oncology (SSO) Research and Executive Committees and sent by SSO to its members. RESULTS: A total of 121 SSO members completed the survey, 77.7% (94/121) of whom were based in the United States. Breast surgeons were more likely than their peers to refer patients to neoadjuvant therapy (p = 0.000171). Head and neck surgeons were more likely to refer patients to definitive nonoperative treatment (p = 0.044), while melanoma surgeons were less likely to do so (p = 0.029). In all, 79.2% (95/120) of respondents are currently using telemedicine. US surgeons were more likely to use telemedicine (p = 0.004). Surgeons believed telemedicine is useful for long-term/surveillance visits (70.2%, 80/114) but inappropriate (50.4%, 57/113) for new patient visits. CONCLUSION: COVID-19 pandemic resulted in increased use of neoadjuvant therapy, delays in operative procedures, and increased use of telemedicine. Telemedicine is perceived to be most efficacious for long-term/surveillance visits or postoperative visits.

Neoadjuvant Therapy for Pancreatic Cancer: Increased Use and Improved Optimal Outcomes.

BACKGROUND: The introduction of more effective chemotherapy a decade ago has led to increased use of neoadjuvant therapy (NAT) in patients with pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to assess the evolving use of NAT in individuals with PDAC undergoing pancreatoduodenectomy (PD) and to compare their outcomes with patients undergoing upfront operation. STUDY DESIGN: The American College of Surgeons NSQIP Procedure Targeted Pancreatectomy database was queried from 2014 to 2019. Patients undergoing pancreatoduodenectomy were evaluated based on the use of NAT versus upfront operation. Multivariable analysis was performed to determine the effect of NAT on postoperative outcomes, including the composite measure optimal pancreatic surgery (OPS). Mann-Kendall trend tests were performed to assess the use of NAT and associated outcomes over time. RESULTS: A total of 13,257 patients were identified who underwent PD for PDAC between 2014 and 2019. Overall, 33.6% of patients received NAT. The use of NAT increased steadily from 24.2% in 2014 to 42.7% in 2019 (p < 0.0001). On multivariable analysis, NAT was associated with reduced serious morbidity (odds ratio [OR] 0.83, p < 0.001), clinically relevant pancreatic fistulas (OR 0.52, p < 0.001), organ space infections (OR 0.74, p < 0.001), percutaneous drainage (OR 0.73, p < 0.001), reoperation (OR 0.76, p = 0.005), and prolonged length of stay (OR 0.63, p < 0.001). OPS was achieved more frequently in patients undergoing NAT (OR 1.433, p < 0.001) and improved over time in patients receiving NAT (50.7% to 56.6%, p < 0.001). CONCLUSION: NAT before pancreatoduodenectomy increased more than 3-fold over the past decade and was associated with improved optimal operative outcomes.

Colorectal Cancer Survivors' Receptivity toward Genomic Testing and Targeted Use of Non-Steroidal Anti-Inflammatory Drugs to Prevent Cancer Recurrence.

Genomic testing and targeted use of non-steroidal anti-inflammatory drugs (NSAIDs) may mitigate cancer recurrence risks. This study examines colorectal cancer (CRC) survivors' interest and receptivity to these strategies. Patients diagnosed with stage I-III CRC in 2004-2012 were recruited through the New Mexico Cancer Registry to complete a cancer survivorship experiences survey. We assessed interest in genomic testing, daily aspirin (ASA) and NSAID use, and receptivity to future daily ASA/NSAIDs. Descriptive statistics and multivariable logistic regression models estimated factors associated with genomic testing interest. Receptivity to future ASA/NSAIDs use was estimated for non-users of ASA/NSAIDs. Among CRC survivors (n = 273), 83% endorsed interest in genomic testing, 25% were ASA users and 47% ASA/NSAIDs users. In our final model, genomic testing interest was associated with being uncoupled [OR = 4.11; 95% CI = 1.49-11.35], low income [OR = 0.35, 95% CI: 0.14-0.88], smoking history [OR = 0.35, 95% CI: 0.14-0.90], low [OR: 0.33, 95% CI: 0.07-1.43] and moderate [OR: 0.26, 95% CI: 0.11-0.61] health literacy, and personal CRC risk worry [OR: 2.86, 95% CI: 1.63-5.02, p = 0.0002]. In our final model, ASA use was associated with age [OR: 1.05, 95% CI: 1.01-1.10] and cardiovascular disease history [OR: 2.42, 95% CI: 1.23-4.73, p = 0.010]. Among non-users ASA/NSAIDs, 83% reported receptivity to ASA/NSAIDs to reduce cancer risks, and no significant correlates were identified. The majority of survivors' expressed genomic testing interest and endorsed receptivity toward ASA/NSAIDs use for cancer risk management. Further research to optimize ASA/NSAIDs use guided by genomic testing is warranted.

Use of Erector Spinae Fascial Plane Blocks in Enhanced Recovery for Open Abdominal Surgery.

BACKGROUND: Bilateral erector spinae fascial plane blocks (ESPB) offers a novel, alternative method of regional post-operative pain control to thoracic epidural analgesia (TEA). The aim of this study was to compare rates of postoperative hypotension, and other standard enhanced recovery after surgery (ERAS) endpoints, in patients receiving ESPB versus TEA for open hepatopancreaticobiliary (HPB) surgery. MATERIALS AND METHODS: This retrospective analysis compared historical controls of ERAS patients undergoing open HPB surgery with TEA versus ESPB. The incidence of postoperative hypotension and clinical outcomes, including opioid requirements, were compared. RESULTS: Forty patients receiving TEA were compared to 27 ESPB patients. Return of bowel function and length of stay (mean 7.2 versus7.4 days; P = 0.83) were similar. ESPB patients received less intraoperative colloid (142cc versus 340cc; P = 0.01) and had less postoperative hypotension versus TEA (22% versus 55%; P = 0.03). No ESPB patient required patient-controlled analgesia (versus 32.5% TEA; P< 0.001). ESPB MME requirements decreased over time, while TEA MME requirements increased over 72 hours (P = 0.019). CONCLUSIONS: ESPB is a novel method that shows promising outcomes in improving enhanced recovery parameters and minimizing opioid administration in open HPB surgery.

Assessing the immediate impact of COVID-19 on surgical oncology practice: Experience from an NCI-designated Comprehensive Cancer Center in the Northeastern United States.

BACKGROUND: The effects of the coronavirus disease 2019 (COVID-19) pandemic on surgical oncology practice are not yet quantified. The aim of this study was to measure the immediate impact of COVID-19 on surgical oncology practice volume. METHODS: A retrospective study of patients treated at an NCI-Comprehensive Cancer Center was performed. "Pre-COVID" era was defined as January-February 2020 and "COVID" as March-April 2020. Primary outcomes were clinic visits and operative volume by surgical oncology subspecialty. RESULTS: Abouyt 907 new patient visits, 3897 follow-up visits, and 644 operations occurred during the study period. All subspecialties experienced significant decreases in new patient visits during COVID, though soft tissue oncology (Mel/Sarc), gynecologic oncology (Gyn/Onc), and endocrine were disproportionately affected. Telehealth visits increased to 11.4% of all visits by April. Mel/Sarc, Gyn/Onc, and Breast experienced significant operative volume decreases during COVID (25.8%, p = 0.012, 43.6% p < 0.001, and 41.9%, p < 0.001, respectively), while endocrine had no change and gastrointestinal oncology had a slight increase (p = 0.823) in the number of cases performed. CONCLUSIONS: The effects of the COVID-19 pandemic are wide-ranging within surgical oncology subspecialties. The addition of telehealth is a viable avenue for cancer patient care and should be considered in surgical oncology practice.

Evaluation of a Gene Expression Profiling Assay in Primary Cutaneous Melanoma.

BACKGROUND: A significant proportion of deaths from cutaneous melanoma occur among patients with an initial diagnosis of stage 1 or 2 disease. The Decision-Dx Melanoma (DDM) 31-gene assay attempts to stratify these patients by risk of recurrence. This study aimed to evaluate this assay in a large single-institution series. METHODS: A retrospective chart review of all patients who underwent surgery for melanoma at a large academic cancer center with DDM results was performed. Patient demographics, tumor pathologic characteristics, sentinel node status, gene expression profile (GEP) class, and recurrence-free survival (RFS) were reviewed. The primary outcomes were recurrence of melanoma and distant metastatic recurrence. RESULTS: Data from 361 patients were analyzed. The median follow-up period was 15 months. Sentinel node biopsy was performed for 75.9% (n = 274) of the patients, 53 (19.4%) of whom tested positive. Overall, 13.6% (n = 49) of the patients had recurrence, and 8% (n = 29) had distant metastatic recurrence. The 3- and 5-year RFS rates were respectively 85% and 75% for the class 1A group, 74% and 47% for the class 1B/class 2A group, and 54% and 45% for the class 2B group. Increased Breslow thickness, ulceration, mitoses, sentinel node biopsy positivity, and GEP class 2B status were significantly associated with RFS and distant metastasis-free survival (DMFS) in the univariate analysis (all p < 0.05). In the multivariate analysis, only Breslow thickness and ulceration were associated with RFS (p < 0.003), and only Breslow thickness was associated with DMFS (p < 0.001). CONCLUSION: Genetic profiling of cutaneous melanoma can assist in predicting recurrence and help determine the need for close surveillance. However, traditional pathologic factors remain the strongest independent predictors of recurrence risk.

Disparities in utilization of services for racial and ethnic minorities with hepatocellular carcinoma associated with hepatitis C.

BACKGROUND: Hepatitis C affects racial minorities disproportionately and is greatest among the black population. The incidence of hepatocellular carcinoma has increased with the largest increase observed in black and Hispanic populations, but limited data remain on whether hepatitis C hepatocellular carcinoma in racial-ethnic minorities have the same utilization of services compared with the white population. METHODS: We used the database of the National Inpatient Sample to identify hepatitis C-hepatocellular carcinoma patients (N = 200,163) who underwent liver transplantation (n = 11,491), liver resection (n = 4,896), or ablation of liver lesions (n = 6,933) from 2005 to 2015. We estimated utilization over time and assessed differences in utilization and inpatient mortality across patient characteristics. RESULTS: In multivariate analysis, factors associated with utilization of services included treatment year, sex, race, insurance status, hospital type, and comorbidity burden, with black and Hispanic patients having statistically significantly decreased utilization. Factors associated with inpatient mortality included treatment year, sex, race, insurance status, hospital type, hospital region, and comorbidity burden, with black patients having a statistically significantly greater risk of inpatient mortality. CONCLUSION: We identified racial and socioeconomic factors which were associated with utilization of services and inpatient mortality for patients with hepatitis C hepatocellular carcinoma. Blacks were especially disadvantaged in the receipt of care. Further work to abrogate these findings is imperative to ensure equitable provision of surgical therapies.

Peritoneal mesothelioma.

Malignant peritoneal mesothelioma (MPM) is a rare and lethal disease of the peritoneal lining, with high variability in biologic aggressiveness. Morbidity and mortality of the disease are related to progressive locoregional effects within the abdominal cavity, such as distention, pain, early satiety, and decreased oral intake that can ultimately lead to bowel obstruction and cachexia. The standard of care for patients with resectable disease remains cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC), with potential survival outcomes greater than 5 years in appropriately selected patients. Patients with inoperable MPM can be offered systemic treatment, although the disease is usually refractory to standard chemotherapic regimens. Patients with MPM should be treated at high volume centers with strong consideration for inclusion in tumor registries and clinical trials. In 2020, research will continue to explore promising genetic and immunologic targets and focus on refinement of surgical methods to optimize CRS-HIPEC approaches.

Pancreatic Adenocarcinoma in New Mexico Native Americans: Disparities in Treatment and Survival.

In this study, we examined the treatment and outcomes of pancreatic adenocarcinoma in New Mexico Native Americans (NA). METHODS: A retrospective review of patients treated for pancreatic adenocarcinoma at a university cancer center from 2002-2016 comparing demographic characteristics, disease presentation, treatment, and outcomes among three main ethnic groups in New Mexico. RESULTS: We identified 457 patients: 240 (52.5%) non-Hispanic Whites, 186 (40.7%) Hispanics, and 31 (6.8%) NA. Non-Hispanic Whites (OR 2.41; p=.026) and Hispanics (OR 2.37; p=.032) were more likely to receive or be offered chemotherapy than NA. More NA than non-Hispanic Whites died within one month of diagnosis (25.8% and 7.5%, respectively; p=.004). The NAs demonstrated a 26.2% one-year survival (CI 11.7-43.3), compared with 48.3% in non-Hispanic Whites (CI 40.9-55.2; p=.015). CONCLUSION: Significant disparities exist in the treatment and outcomes of pancreatic adenocarcinoma in New Mexico NA populations.

Tumor Heterogeneity as a Predictor of Response to Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer.

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) is the standard of care for locally advanced adenocarcinoma of the rectum, but it is currently unknown which patients have disease that will respond. This study tested the correlation between response to nCRT and intratumoral heterogeneity using next-generation sequencing assays. PATIENTS AND METHODS: DNA was extracted from formalin-fixed, paraffin-embedded biopsy samples from a cohort of patients with locally advanced rectal adenocarcinoma (T3/4 or N1/2 disease) who received nCRT. High read-depth sequencing of > 400 cancer-relevant genes was performed. Tumor mutations and variant allele frequencies were used to calculate mutant-allele tumor heterogeneity (MATH) scores as measures of intratumoral heterogeneity. Response to nCRT was pathologically scored after surgical resection. RESULTS: Biopsy samples from 21 patient tumors were analyzed. Eight patients had disease noted to have complete response, 2 moderate, 4 minimal, and 7 poor. Higher MATH scores correlated with poorer response to treatment, demonstrating significantly increased tumor heterogeneity compared to complete response (P = .039). CONCLUSION: The application of MATH scores as a measure of tumor heterogeneity may provide a useful biomarker for treatment response in locally advanced rectal cancer.

Operating room staff and surgeon documentation curriculum improves wound classification accuracy.

BACKGROUND: Misclassification of wounds in the operating room (OR) can adversely affect surgical site infection (SSI) reporting and reimbursement. This study aimed to measure the effects of a curriculum on documentation of surgical wound classification (SWC) for operating room staff and surgeons. METHODS: Accuracy of SWC was determined by comparing SWC documented by OR staff during the original operation to SWC determined by in-depth chart review. Patients 18 years or older undergoing inpatient surgical procedures were included. Two plan-do-act-study (PDSA) cycles were implemented over the course of 9 months. A total of 747 charts were reviewed. Accuracy of SWC documentation was retrospectively assessed across 248 randomly selected surgeries during a 5-week period prior to interventions and compared to 244 cases and 255 cases of post-intervention data from PDSA1 and PDSA2, respectively. Changes in SWC accuracy were assessed pre- and post-intervention using the kappa coefficient. A p-value for change in agreement was computed by comparing pre- and post-intervention kappa. RESULTS: Inaccurate documentation of surgical wound class decreased significantly following curriculum implementation (kappa improved from 0.553 to 0.739 and 0.757; p = 0.001). Classification accuracy improved across all wound classes; however, class III and IV wounds were more frequently misclassified than class I and II wounds, both before and after the intervention. CONCLUSION: Implementation of a multidisciplinary documentation curriculum resulted in a significant decrease in SWC documentation error. Improved accuracy of SWC reporting may facilitate a better assessment of SSI risk in a complex patient population.

KRAS biomarker testing disparities in colorectal cancer patients in New Mexico.

INTRODUCTION: American Society of Clinical Oncology (ASCO) guidelines recommend that all patients with metastatic colorectal cancer (mCRC) receive KRAS testing to guide anti-EGFR monoclonal antibody treatment. The aim of this study was to assess for disparities in KRAS testing and mutational status. METHODS: The New Mexico Tumor Registry (NMTR), a population-based cancer registry participating in the National Cancer Institute's Surveillance, Epidemiology and End Results program, was queried to identify all incident cases of CRC diagnosed among New Mexico residents from 2010 to 2013. RESULTS: Six hundred thirty-seven patients were diagnosed with mCRC from 2010-2013. As expected, KRAS testing in Stage 4 patients presented the highest frequency (38.4%), though testing in stage 3 (8.5%), stage 2 (3.4%) and stage 1 (1.2%) was also observed. In those with metastatic disease, younger patients (≤ 64 years) were more likely to have had testing than patients 65 years and older (p < 0.0001). Patients residing in urban areas received KRAS testing more often than patients living in rural areas (p = 0.019). No significant racial/ethnic disparities were observed (p = 0.66). No significant differences were seen by year of testing. CONCLUSION: Age and geographic disparities exist in the rates of KRAS testing, while sex, race/ethnicity and the year tested were not significantly associated with testing. Further study is required to assess the reasons for these disparities and continued suboptimal adherence to current ASCO KRAS testing guidelines.

KRAS Testing, Tumor Location, and Survival in Patients With Stage IV Colorectal Cancer: SEER 2010-2013.

Purpose:KRAS mutations and tumor location have been associated with response to targeted therapy among patients with stage IV colorectal cancer (CRC) in various trials. This study performed the first population-based examination of associations between KRAS mutations, tumor location, and survival, and assessed factors associated with documented KRAS testing. Methods: Patients with stage IV adenocarcinoma of the colon/rectum diagnosed from 2010 to 2013 were extracted from SEER data. Analyses of patient characteristics, KRAS testing, and tumor location were conducted using logistic regression. Cox proportional hazards models assessed relationships between KRAS mutations, tumor location, and risk of all-cause death. Results: Of 22,542 patients, 30% received KRAS testing, and 44% of these had mutations. Those tested tended to be younger, married, and metropolitan area residents, and have private insurance or Medicare. Rates of KRAS testing also varied by registry (range, 20%-46%). Patients with right-sided colon cancer (vs left-sided) tended to be older, female, and black; have mucinous, KRAS-mutant tumors; and have a greater risk of death (hazard ratio [HR], 1.27; 95% CI, 1.22-1.32). KRAS mutations were not associated with greater risk of death in the overall population; however, they were associated with greater risk of death among patients with left-sided colon cancer (HR, 1.19; 95% CI, 1.05-1.33). Conclusions: This large population-based study showed that among patients initially diagnosed with stage IV CRC, right-sided colon cancer was associated with greater risk of death compared with left-sided cancer, and KRAS mutations were only associated with risk of death in left-sided colon cancer. An unexpected finding was that among patients with stage IV disease, right-sided cancer was more commonly seen in black patients versus whites. Future studies should further explore these associations and determine the role of biology versus treatment differences. In addition, use of KRAS testing is increasing, but there is wide geographic variation wherein disparities related to insurance coverage and rurality may warrant further study.