Perceptions of Readiness for Practice After Complex General Surgical Oncology Fellowship: A Survey Study

BACKGROUND

Surgical subspecialty training aims to meet the needs of practicing surgeons and their communities. This study investigates career preparedness of Complex General Surgical Oncology (CGSO) fellowship graduates, identifies factors associated with practice readiness, and explores potential opportunities to improve the current training model.

METHODS

The Society of Surgical Oncology partnered with the National Cancer Institute to conduct a 36-question survey of CGSO fellowship graduates from 2012 to 2022.

RESULTS

The overall survey response rate was 38% (221/582) with a slight male predominance (63%). Forty-six percent of respondents completed their fellowship after 2019. Factors influencing fellowship program selection include breadth of cancer case exposure (82%), mentor influence (66%), and research opportunities (38%). Overall, graduates reported preparedness for practice; however, some reported unpreparedness in research (18%) and in specific clinical areas: thoracic (43%), hyperthermic intraperitoneal chemotherapy (HIPEC) (15%), and hepato-pancreato-biliary (15%) surgery. Regarding technical preparedness, 70% reported being "very prepared". Respondents indicated lack of preparedness in robotic (63%) and laparoscopic (33%) surgery approaches. Suggestions for training improvement included increased autonomy and case volumes, program development, and research infrastructure. Current practice patterns by graduates demonstrated discrepancies between ideal contracts and actual practice breakdowns, particularly related to the practice of general surgery.

CONCLUSIONS

This study of CGSO fellowship graduates demonstrates potential gaps between trainee expectations and the realities of surgical oncology practice. Although CGSO fellowship appears to prepare surgeons for careers in surgical oncology, there may be opportunities to refine the training model to better align with the needs of practicing surgical oncologists.

Progression of Site-Specific Recurrence of Pancreatic Cancer and Implications for Treatment

OBJECTIVE

This study aimed to analyze post-recurrence progression in context of recurrence sites and assess implications for post-recurrence treatment.

BACKGROUND

Most patients with resected pancreatic ductal adenocarcinoma (PDAC) recur within two years. Different survival outcomes for location-specific patterns of recurrence are reported, highlighting their prognostic value. However, a lack of understanding of post-recurrence progression and survival remains.

METHODS

This retrospective analysis included surgically treated PDAC patients at the NYU-Langone Health (2010-2021). Sites of recurrence were identified at time of diagnosis and further follow-up. Kaplan-Meier curves, log-rank test, and Cox-regression analyses were applied to assess survival outcomes.

RESULTS

Recurrence occurred in 57.3% (196/342) patients with a median time to recurrence of 11.3 months (95%CI:12.6 to 16.5). First site of recurrence was local in 43.9% patients, liver in 23.5%, peritoneal in 8.7%, lung in 3.6%, while 20.4% had multiple sites of recurrence. Progression to secondary sites was observed in 11.7%. Only lung involvement was associated with significantly longer survival after recurrence compared to other sites (16.9 months vs. 8.49 months, P=0.003). In local recurrence, 21 (33.3%) patients were alive after one year without progression to secondary sites. This was associated with a CA19-9 of <100U/ml at time of primary diagnosis (P=0.039), nodal negative disease (P=0.023), and well-moderate differentiation (P=0.042) compared to patients with progression.

CONCLUSION

Except for lung recurrence, post-recurrence survival after PDAC resection is associated with poor survival. A subset of patients with local-only recurrence do not quickly succumb to systemic spread. This is associated with markers for favorable tumor biology, making them candidates for potential curative re-resections when feasible.

Natural History of Stage IV Pancreatic Cancer. Identifying Survival Benchmarks for Curative-intent Resection in Patients With Synchronous Liver-only Metastases

OBJECTIVE

To evaluate long-term oncologic outcomes of patients with stage IV pancreatic ductal adenocarcinoma and to identify survival benchmarks for comparison when considering resection in these patients.

BACKGROUND

Highly selected cohorts of patients with liver-oligometastatic pancreas cancer have reported prolonged survival after resection. The long-term impact of surgery in this setting remains undefined because of a lack of appropriate control groups.

METHODS

We identified patients with clinical stage IV pancreatic ductal adenocarcinoma with synchronous liver metastases within our cancer registry. We estimated overall survival (OS) among various patient subgroups using the Kaplan-Meier method. To mitigate immortal time bias, we analyzed long-term outcomes of patients who survived beyond 12 months (landmark time) from diagnosis.

RESULTS

We identified 241 patients. Median OS was 7 months (95% CI, 5-9), both overall and for patients with liver-only metastasis (n=144). Ninety patients (38% of liver only; 40% of whole cohort) survived at least 12 months; those who received chemotherapy in this subgroup had a median OS of 26 months (95% CI, 17-39). Of these patients, those with resectable or borderline resectable primary tumors and resectable liver-only metastasis (n=9, 4%) had a median OS of 39 months (95% CI, 13-NR).

CONCLUSIONS

The 4% of our cohort that were potentially eligible for surgery experienced a prolonged survival compared with all-comers with stage IV disease. Oncologic outcomes of patients undergoing resection of metastatic pancreas cancer should be assessed in the context of the expected survival of patients potentially eligible for surgery and not relative to all patients with stage IV disease.

A Call to Action to Train Underrepresented Minorities in Surgical Subspecialties and Fellowships

BACKGROUND

With each succession along the surgical career pathway, from medical school to faculty, the percentage of those who identify as underrepresented in medicine (URiM) decreases. We sought to evaluate the demographic trend of surgical fellowship applicants, matriculants, and graduates over time.

STUDY DESIGN

The Electronic Residency Application Service and the Graduate Medical Education Survey for general surgery fellowships in colorectal surgery, surgical oncology, pediatric surgery, thoracic surgery, and vascular surgery were retrospectively analyzed (2005 to 2020). The data were stratified by race and gender, descriptive statistics were performed, and time series were evaluated. Race/ethnicity groups included White, Asian, other, and URiM, which is defined as Black/African American, Hispanic/Latino(a), Alaskan or Hawaiian Native, and Native American.

RESULTS

From 2005 to 2020, there were 5,357 Electronic Residency Application Service applicants, 4,559 matriculants, and 4,178 graduates to surgery fellowships. Whites, followed by Asians, represented the highest percentage of applicants (62.7% and 22.3%, respectively), matriculants (65.4% and 23.8% respectively), and graduates (65.4% and 24.0%, respectively). For URiMs, the applicants (13.4%), matriculants (9.1%), and graduates (9.1%) remained significantly low (p < 0.001). When stratified by both race and gender, only 4.6% of the applicants, 2.7% of matriculants, and 2.4% of graduates identified as both URiM and female compared to White female applicants (20.0%), matriculants (17.9%), and graduates (16.5%, p < 0.001).

CONCLUSIONS

Significant disparities exist for URiMs in general surgery subspecialty fellowships. These results serve as a call to action to re-examine and improve the existing processes to increase the number of URiMs in the surgery subspecialty fellowship training pathway.

International Center-Level Variation in Utilization of Completion Lymph Node Dissection and Adjuvant Systemic Therapy for Sentinel Lymph Node-Positive Melanoma at Major Referral Centers

OBJECTIVE

The aim of this study was to determine overall trends and center-level variation in utilization of completion lymph node dissection (CLND) and adjuvant systemic therapy for sentinel lymph node (SLN)-positive melanoma.

SUMMARY BACKGROUND DATA

Based on recent clinical trials, management options for SLN-positive melanoma now include effective adjuvant systemic therapy and nodal observation instead of CLND. It is unknown how these findings have shaped practice or how these contemporaneous developments have influenced their respective utilization.

METHODS

We performed an international cohort study at 21 melanoma referral centers in Australia, Europe, and the United States that treated adults with SLN-positive melanoma and negative distant staging from July 2017 to June 2019. We used generalized linear and multinomial logistic regression models with random intercepts for each center to assess center-level variation in CLND and adjuvant systemic treatment, adjusting for patient and disease-specific characteristics.

RESULTS

Among 1109 patients, performance of CLND decreased from 28% to 8% and adjuvant systemic therapy use increased from 29 to 60%. For both CLND and adjuvant systemic treatment, the most influential factors were nodal tumor size, stage, and location of treating center. There was notable variation among treating centers in management of stage IIIA patients and use of CLND with adjuvant systemic therapy versus nodal observation alone for similar risk patients.

CONCLUSIONS

There has been an overall decline in CLND and simultaneous adoption of adjuvant systemic therapy for patients with SLN-positive melanoma though wide variation in practice remains. Accounting for differences in patient mix, location of care contributed significantly to the observed variation.

Outcomes after primary tumor resection of metastatic pancreatic neuroendocrine tumors: An analysis of the National Cancer Database

INTRODUCTION

There is no consensus regarding the role of primary tumor resection for patients with metastatic pancreatic neuroendocrine tumors (panNET). We assessed surgical treatment patterns and evaluated the survival impact of primary tumor resection in patients with metastatic panNET.

METHODS

Patients with synchronous metastatic nonfunctional panNET in the National Cancer Database (2004-2016) were categorized based on whether they underwent primary tumor resection. We used logistic regressions to assess associations with primary tumor resection. We performed survival analyses with Kaplan-Meier survival functions, log-rank test, and Cox proportional hazard regression within a propensity score matched cohort.

RESULTS

In the overall cohort of 2613 patients, 68% (n = 839) underwent primary tumor resection. The proportion of patients who underwent primary tumor resection decreased over time from 36% (2004) to 16% (2016, p < 0.001). After propensity score matching on age at diagnosis, median income quartile, tumor grade, size, liver metastasis, and hospital type, primary tumor resection was associated with longer median overall survival (OS) (65 vs. 24 months; p < 0.001) and was associated with lower hazard of mortality (HR: 0.39, p < 0.001).

CONCLUSION

Primary tumor resection was significantly associated with improved OS, suggesting that, if feasible, surgical resection can be considered for well-selected patients with panNET and synchronous metastasis.

Time to Curative-Intent Surgery in Gastric Cancer Shows a Bimodal Relationship with Overall Survival

BACKGROUND

Time to treatment (TTT) varies widely for patients with gastric cancer. We aimed to evaluate relationships between time to treatment, overall survival (OS), and other surgical outcomes in patients with stage I-III gastric cancer.

METHODS

We identified patients with clinical stage I-III gastric cancer who underwent curative-intent gastrectomy within the National Cancer Database (2006-2015) and grouped them by treatment sequence: neoadjuvant chemotherapy or surgery upfront. We defined TTT as weeks from diagnosis to treatment initiation (neoadjuvant chemotherapy or definitive surgical procedure, respectively). Survival differences were assessed by Kaplan-Meier estimate, Cox proportional hazard regression, and log rank test.

RESULTS

Among the 22,846 patients with stage I-III gastric cancer, most (56%) received surgery upfront. Median TTT was 5 weeks (IQR 4-7) and 6 weeks (IQR 3-9) for patients in the neoadjuvant and surgery upfront groups, respectively. In the neoadjuvant group, increasing TTT was significantly associated with increasing median OS up to TTT of 5 weeks, with no change in median OS when TTT was > 5 weeks. In the surgery group, increasing TTT was significantly associated with increasing median OS up to 6 weeks; however, increasing TTT between 14 and 21 weeks was associated with decreasing median OS.

CONCLUSIONS

The relationship between time to treatment and survival outcomes is non-linear. Among patients who underwent surgery upfront, the relationship between time to treatment and OS was bimodal, suggesting that deferring definitive surgery, up to 14 weeks, is not associated with worse OS or oncologic outcomes. The relationship between time to treatment and overall survival among patients was bimodal, suggesting that deferring definitive surgery up to 14 weeks is not associated with worse OS.

Regional Patterns of Hospital-Level Guideline Adherence in Gastric Cancer: An Analysis of the National Cancer Database

BACKGROUND

Adherence to evidence-based guidelines for gastric cancer is low, particularly at the hospital level, despite a strong association with improved overall survival (OS). We aimed to evaluate patterns of hospital and regional adherence to National Comprehensive Cancer Network guidelines for gastric cancer.

METHODS

Using the National Cancer Database (2004-2015), we identified patients with stage I-III gastric cancer. Hospital-level guideline adherence was calculated by dividing the patients who received guideline adherent care by the total patients treated at that hospital. OS was estimated for each hospital. Associations between adherence, region, and survival were compared using mixed-effects, hierarchical regression.

RESULTS

Among 576 hospitals, the median hospital guideline adherence rate was 25% (range 0-76%) and varied significantly by region (p = 0.001). Adherence was highest in the Middle Atlantic (29%) and lowest in the East South Central region (19%); hospitals in the New England, Middle Atlantic, and East North Central regions were more likely to be guideline adherent than those in the East South Central region (all p < 0.05), after adjusting for patient and hospital mix. Most (35%) of the adherence variation was attributable to the hospital. Median 2-year OS varied significantly by region. After adjusting for hospital and patient mix, hazard of mortality was 17% lower in the Middle Atlantic (hazard ratio 0.82, 95% confidence interval 0.74-0.90) relative to the East South Central region, with most of the variation (54%) attributable to patient-level factors.

CONCLUSIONS

Hospital-level guideline adherence for gastric cancer demonstrated significant regional variation and was associated with longer OS, suggesting that efforts to improve guideline adherence should be directed toward lower-performing hospitals.

Associations between TERT Promoter Mutations and Survival in Superficial Spreading and Nodular Melanomas in a Large Prospective Patient Cohort

Survival outcomes in melanoma and their association with mutations in the telomerase reverse transcriptase gene TERT promoter remain uncertain. In addition, few studies have examined whether these associations are affected by a nearby common germline polymorphism or vary on the basis of melanoma histopathological subtype. We analyzed 408 primary tumors from a prospective melanoma cohort for somatic TERT-124[C>T] and TERT-146[C>T] mutations, the germline polymorphism rs2853669, and BRAFV600 and NRASQ61 mutations. We tested the associations between these variants and clinicopathologic factors and survival outcomes. TERT-124[C>T] was associated with thicker tumors, ulceration, mitoses (>0/mm2), nodular histotype, and CNS involvement. In a multivariable model controlling for the American Joint Committee on Cancer stage, TERT-124[C>T] was an independent predictor of shorter recurrence-free survival (hazard ratio = 2.58, P = 0.001) and overall survival (hazard ratio = 2.47, P = 0.029). Patients with the germline variant and TERT-124[C>T]-mutant melanomas had significantly shorter recurrence-free survival than those lacking either or both sequence variants (P < 0.04). The impact of the germline variant appeared to be more pronounced in superficial spreading than in nodular melanoma. No associations were found between survival and TERT-146[C>T], BRAF, or NRAS mutations. These findings strongly suggest that TERT-124[C>T] mutation is a biomarker of aggressive primary melanomas, an effect that may be modulated by rs2853669.

Diagnostic laparoscopy is underutilized in the staging of gastric adenocarcinoma regardless of hospital type: An US safety net collaborative analysis

BACKGROUND

Diagnostic laparoscopy (DL) is a key component of staging for locally advanced gastric adenocarcinoma (GA). We hypothesized that utilization of DL varied between safety net (SNH) and affiliated tertiary referral centers (TRCs).

METHODS

Patients diagnosed with primary GA eligible for DL were identified from the US Safety Net Collaborative database (2012-2014). Clinicopathologic factors were analyzed for association with use of DL and findings on DL. Overall survival (OS) was analyzed by Kaplan-Meier method.

RESULTS

Among 233 eligible patients, 69 (30%) received DL, of which 24 (35%) were positive for metastatic disease. Forty percent of eligible SNH patients underwent DL compared to 21.5% at TRCs. Lack of insurance was significantly associated with decreased use of DL (OR 0.48, p < 0.01), while African American (OR 6.87, p = 0.02) and Asian race (OR 3.12, p ≤ 0.01), signet ring cells on biopsy (OR 3.14, p < 0.01), and distal tumors (OR 1.62, p < 0.01) were associated with increased use. Median OS of patients with a negative DL was better than those without DL or a positive DL (not reached vs. 32 vs. 12 months, p < 0.005, Figure 1).

CONCLUSIONS

Results from DL are a strong predictor of OS in GA; however, the procedure is underutilized. Patients from racial minority groups were more likely to undergo DL, which likely accounts for higher DL rates among SNH patients.

Adherence to guidelines at the patient- and hospital-levels is associated with improved overall survival in patients with gastric cancer

BACKGROUND AND OBJECTIVES

Adherence to evidence-based guidelines in gastric cancer is low. We aimed to evaluate adherence to National Comprehensive Cancer Network (NCCN) Guidelines for gastric cancer at both patient- and hospital-levels and examine associations between guideline adherence and treatment outcomes, including overall survival (OS).

METHODS

We applied stage-specific, annual NCCN Guidelines (2004-2015) to patients with gastric cancer treated with curative-intent within the National Cancer Database and compared characteristics of patients who did and did not receive guideline-adherent care. Hospitals were evaluated by guideline adherence rate. We identified associations with OS through multivariable Cox regression.

RESULTS

Of 37 659 patients included, 32% received NCCN Guideline-adherent treatment. OS was significantly associated with both guideline adherence (51 months for patients receiving guideline-adherent treatment vs. 22 for patients receiving nonadherent treatment, p < 0.001). Treatment at a hospital with higher adherence was associated with longer OS (21 months for patients treated at lowest adherence quartile hospitals vs. 37 months at highest adherence quartile hospitals, p < 0.001), regardless of type of treatment received.

CONCLUSIONS

Guideline-adherent treatment was strongly associated with longer median OS. Guideline adherence should be used as a benchmark for focused quality improvement for physicians taking care of patients with gastric cancer and institutions at large.

Outcomes with adjuvant anti-PD-1 therapy in patients with sentinel lymph node-positive melanoma without completion lymph node dissection

Until recently, most patients with sentinel lymph node-positive (SLN+) melanoma underwent a completion lymph node dissection (CLND), as mandated in published trials of adjuvant systemic therapies. Following multicenter selective lymphadenectomy trial-II, most patients with SLN+ melanoma no longer undergo a CLND prior to adjuvant systemic therapy. A retrospective analysis of clinical outcomes in SLN+ melanoma patients treated with adjuvant systemic therapy after July 2017 was performed in 21 international cancer centers. Of 462 patients who received systemic adjuvant therapy, 326 patients received adjuvant anti-PD-1 without prior immediate (IM) CLND, while 60 underwent IM CLND. With median follow-up of 21 months, 24-month relapse-free survival (RFS) was 67% (95% CI 62% to 73%) in the 326 patients. When the patient subgroups who would have been eligible for the two adjuvant anti-PD-1 clinical trials mandating IM CLND were analyzed separately, 24-month RFS rates were 64%, very similar to the RFS rates from those studies. Of these no-CLND patients, those with SLN tumor deposit >1 mm, stage IIIC/D and ulcerated primary had worse RFS. Of the patients who relapsed on adjuvant anti-PD-1, those without IM CLND had a higher rate of relapse in the regional nodal basin than those with IM CLND (46% vs 11%). Therefore, 55% of patients who relapsed without prior CLND underwent surgery including therapeutic lymph node dissection (TLND), with 30% relapsing a second time; there was no difference in subsequent relapse between patients who received observation vs secondary adjuvant therapy. Despite the increased frequency of nodal relapses, adjuvant anti-PD-1 therapy may be as effective in SLN+ pts who forego IM CLND and salvage surgery with TLND at relapse may be a viable option for these patients.

Outcomes After Surgical Palliation of Patients With Gastric Cancer

INTRODUCTION

Surgery is an option for symptom palliation in patients with metastatic gastric cancer. Operative outcomes after palliative interventions are largely unknown. Herein, we assess the trends of surgical palliation use for patients with gastric cancer and describe outcomes of patients undergoing surgical palliation compared to nonsurgical palliation.

METHODS

Patients with clinical Stage IV gastric cancer in the National Cancer Database (2004-2015) who received surgical or nonsurgical palliation were selected. We identified factors associated with palliative surgery. Survival differences were assessed by Kaplan-Meier estimate, Cox proportional hazard regression, and log rank test.

RESULTS

Six thousand eight hundred twenty nine patients received palliative care for gastric cancer. Most patients (87%, n = 5944) received nonsurgical palliation: 29% radiation therapy, 57% systemic treatment, and 14% pain management. The number of patients receiving palliative care increased between 2004 and 2015; however, use of surgical palliation declined significantly (22% in 2004, 8% in 2015; P < 0.001). Median overall survival (OS) for the cohort was 5.65 mo (95% confidence interval 5.45-5.85); 1-year and 2-year OS were 24% and 9%, respectively. Older age at diagnosis and diagnosis between 2004 and 2006 were significantly associated with undergoing surgical palliation. Patients who underwent surgical palliation had significantly shorter median OS and a 20% higher hazard of mortality than those who received nonsurgical palliation.

CONCLUSIONS

Patients with metastatic gastric cancer experience very short survival. While palliative surgery is used infrequently, the observed association with shorter median OS underscores the importance of careful patient selection. Palliative surgery should be offered judiciously and expectations about outcomes clearly established.

The efficacy of immune checkpoint blockade for melanoma in-transit with or without nodal metastases - A multicenter cohort study

PURPOSE

Guidelines addressing melanoma in-transit metastasis (ITM) recommend immune checkpoint inhibitors (ICI) as a first-line treatment option, despite the fact that there are no efficacy data available from prospective trials for exclusively ITM disease. The study aims to analyze the outcome of patients with ITM treated with ICI based on data from a large cohort of patients treated at international referral clinics.

METHODS

A multicenter retrospective cohort study of patients treated between January 2015 and December 2020 from Australia, Europe, and the USA, evaluating treatment with ICI for ITM with or without nodal involvement (AJCC8 N1c, N2c, and N3c) and without distant disease (M0). Treatment was with PD-1 inhibitor (nivolumab or pembrolizumab) and/or CTLA-4 inhibitor (ipilimumab). The response was evaluated according to the RECIST criteria modified for cutaneous lesions.

RESULTS

A total of 287 patients from 21 institutions in eight countries were included. Immunotherapy was first-line treatment in 64 (22%) patients. PD-1 or CTLA-4 inhibitor monotherapy was given in 233 (81%) and 23 (8%) patients, respectively, while 31 (11%) received both in combination. The overall response rate was 56%, complete response (CR) rate was 36%, and progressive disease (PD) rate was 32%. Median PFS was ten months (95% CI 7.4-12.6 months) with a one-, two-, and five-year PFS rate of 48%, 33%, and 18%, respectively. Median MSS was not reached, and the one-, two-, and five-year MSS rates were 95%, 83%, and 71%, respectively.

CONCLUSION

Systemic immunotherapy is an effective treatment for melanoma ITM. Future studies should evaluate the role of systemic immunotherapy in the context of multimodality therapy, including locoregional treatments such as surgery, intralesional therapy, and regional therapies.

Surgical Treatment of Patients with Poorly Differentiated Pancreatic Neuroendocrine Carcinoma: An NCDB Analysis

BACKGROUND

Consensus guidelines discourage resection of poorly differentiated pancreatic neuroendocrine carcinoma (panNEC) given its association with poor long-term survival. This study assessed treatment patterns and outcomes for this rare malignancy using the National Cancer Database (NCDB).

METHODS

Patients with non-functional pancreatic neuroendocrine tumors in the NCDB (2004-2016) were categorized based on pathologic differentiation. Logistic and Cox proportional hazard regressions identified associations with resection and overall survival (OS). Survival was compared using Kaplan-Meier and log-rank tests.

RESULTS

Most patients (83%) in the cohort of 8560 patients had well-differentiated tumors (panNET). The median OS was 47 months (panNET, 63 months vs panNEC, 17 months; p < 0.001). Surgery was less likely for older patients (odds ratio [OR], 0.97), patients with panNEC (OR, 0.27), and patients with metastasis at diagnosis (OR, 0.08) (all p < 0.001). After propensity score-matching of these factors, surgical resection was associated with longer OS (82 vs 29 months; p < 0.001) and a decreased hazard of mortality (hazard ratio [HR], 0.37; p < 0.001). Surgery remained associated with longer OS when stratified by differentiation (98 vs 41 months for patients with panNET and 36 vs 8 months for patients with panNEC). Overall survival did not differ between patients with panNEC who underwent surgery and patients with panNET who did not (both 39 months; p = 0.294).

CONCLUSIONS

Poorly differentiated panNEC exhibits poorer survival than well-differentiated panNET. In the current cohort, surgical resection was strongly and independently associated with improved OS, suggesting that patients with panNEC who are suitable operative candidates should be considered for multimodality therapy, including surgery.

Acral Lentiginous Melanoma: A United States Multi-Center Substage Survival Analysis

Background

Acral lentiginous melanoma is associated with worse survival than other subtypes of melanoma. Understanding prognostic factors for survival and recurrence can help better inform follow-up care.

Objectives

To analyze the clinicopathologic features, melanoma-specific survival, and recurrence-free survival by substage in a large, multi-institutional cohort of primary acral lentiginous melanoma patients.

Methods

Retrospective review of the United States Melanoma Consortium database, a multi-center prospectively collected database of acral lentiginous melanoma patients treated between January 2000 and December 2017.

Results

Of the 433 primary acral lentiginous melanoma patients identified (median [range] age: 66 [8–97] years; 53% female, 83% white), 66% presented with stage 0–2 disease and the median time of follow-up for the 392 patients included in the survival analysis was 32.5 months (range: 0–259). The 5-year melanoma-specific survivals by stage were 0 = 100%, I = 93.8%, II = 76.2%, III = 63.4%, IIIA = 80.8%, and IV = 0%. Thicker Breslow depth ((HR) = 1.13; 95% CI = 1.05–1.21; P < .001)) and positive nodal status ((HR) = 1.79; 95% CI = 1.00–3.22; P = .050)) were independent prognostic factors for melanoma-specific survival. Breslow depth ((HR = 1.13; 95% CI = 1.07–1.20; P < .001), and positive nodal status (HR = 2.12; 95% CI = 1.38–3.80; P = .001) were also prognostic factors for recurrence-free survival.

Conclusion

In this cohort of patients, acral lentiginous melanoma was associated with poor outcomes even in early stage disease, consistent with prior reports. Stage IIB and IIC disease were associated with particularly low melanoma-specific and recurrence-free survival. This suggests that studies investigating adjuvant therapies in stage II patients may be especially valuable in acral lentiginous melanoma patients.

Management of Noncutaneous Melanomas

Noncutaneous melanomas are rare subtypes of melanoma with high rates of metastatic disease and poor overall survival. One-third to one-half of cases are amelanotic, which may contribute to a delay in diagnosis. Immunohistochemistry staining with typical melanoma markers helps confirm the diagnosis. There is no standard staging system across mucosal melanomas. Elective nodal dissection is not recommended and there is a paucity of data to support use of sentinel lymph node biopsy. Mutational analysis should be routinely performed. Systemic therapy options include targeted inhibitors, immunotherapy, and cytotoxic chemotherapy, although further studies are needed to confirm their efficacy.

Active surveillance of patients who have sentinel node positive melanoma: An international, multi-institution evaluation of adoption and early outcomes after the Multicenter Selective Lymphadenectomy Trial II (MSLT-2)

BACKGROUND

For patients with sentinel lymph node (SLN)-positive cutaneous melanoma, the Second Multicenter Selective Lymphadenectomy trial demonstrated equivalent disease-specific survival (DSS) with active surveillance using nodal ultrasound versus completion lymph node dissection (CLND). Adoption and outcomes of active surveillance in clinical practice and in adjuvant therapy recipients are unknown.

METHODS

In a retrospective cohort of SLN-positive adults treated at 21 institutions in Australia, Europe, and the United States from June 2017 to November 2019, the authors evaluated the impact of active surveillance and adjuvant therapy on all-site recurrence-free survival (RFS), isolated nodal RFS, distant metastasis-free survival (DMFS), and DSS using Kaplan-Meier curves and Cox proportional hazard models.

RESULTS

Among 6347 SLN biopsies, 1154 (18%) were positive and had initial negative distant staging. In total, 965 patients (84%) received active surveillance, 189 (16%) underwent CLND. Four hundred thirty-nine patients received adjuvant therapy (surveillance, 38%; CLND, 39%), with the majority (83%) receiving anti-PD-1 immunotherapy. After a median follow-up of 11 months, 220 patients developed recurrent disease (surveillance, 19%; CLND, 22%), and 24 died of melanoma (surveillance, 2%; CLND, 4%). Sixty-eight patients had an isolated nodal recurrence (surveillance, 6%; CLND, 4%). In patients who received adjuvant treatment without undergoing prior CLND, all isolated nodal recurrences were resectable. On risk-adjusted multivariable analyses, CLND was associated with improved isolated nodal RFS (hazard ratio [HR], 0.36; 95% CI, 0.15-0.88), but not all-site RFS (HR, 0.68; 95% CI, 0.45-1.02). Adjuvant therapy improved all-site RFS (HR, 0.52; 95% CI, 0.47-0.57). DSS and DMFS did not differ by nodal management or adjuvant treatment.

CONCLUSIONS

Active surveillance has been adopted for most SLN-positive patients. At initial assessment, real-world outcomes align with randomized trial findings, including in adjuvant therapy recipients.

LAY SUMMARY

For patients with melanoma of the skin and microscopic spread to lymph nodes, monitoring with ultrasound is an alternative to surgically removing the remaining lymph nodes. The authors studied adoption and real-world outcomes of ultrasound monitoring in over 1000 patients treated at 21 centers worldwide, finding that most patients now have ultrasounds instead of surgery. Although slightly more patients have cancer return in the lymph nodes with this strategy, typically, it can be removed with delayed surgery. Compared with up-front surgery, ultrasound monitoring results in the same overall risk of melanoma coming back at any location or of dying from melanoma.

Surveillance of Sentinel Node-Positive Melanoma Patients with Reasons for Exclusion from MSLT-II: Multi-Institutional Propensity Score Matched Analysis

BACKGROUND

In sentinel lymph node (SLN)-positive melanoma, two randomized trials demonstrated equivalent melanoma-specific survival with nodal surveillance vs completion lymph node dissection (CLND). Patients with microsatellites, extranodal extension (ENE) in the SLN, or >3 positive SLNs constitute a high-risk group largely excluded from the randomized trials, for whom appropriate management remains unknown.

STUDY DESIGN

SLN-positive patients with any of the three high-risk features were identified from an international cohort. CLND patients were matched 1:1 with surveillance patients using propensity scores. Risk of any-site recurrence, SLN-basin-only recurrence, and melanoma-specific mortality were compared.

RESULTS

Among 1,154 SLN-positive patients, 166 had ENE, microsatellites, and/or >3 positive SLN. At 18.5 months median follow-up, 49% had recurrence (vs 26% in patients without high-risk features, p < 0.01). Among high-risk patients, 52 (31%) underwent CLND and 114 (69%) received surveillance. Fifty-one CLND patients were matched to 51 surveillance patients. The matched cohort was balanced on tumor, nodal, and adjuvant treatment factors. There were no significant differences in any-site recurrence (CLND 49%, surveillance 45%, p = 0.99), SLN-basin-only recurrence (CLND 6%, surveillance 14%, p = 0.20), or melanoma-specific mortality (CLND 14%, surveillance 12%, p = 0.86).

CONCLUSIONS

SLN-positive patients with microsatellites, ENE, or >3 positive SLN constitute a high-risk group with a 2-fold greater recurrence risk. For those managed with nodal surveillance, SLN-basin recurrences were more frequent, but all-site recurrence and melanoma-specific mortality were comparable to patients treated with CLND. Most recurrences were outside the SLN-basin, supporting use of nodal surveillance for SLN-positive patients with microsatellites, ENE, and/or >3 positive SLN.

Optimization of an automated tumor-infiltrating lymphocyte algorithm for improved prognostication in primary melanoma

Tumor-infiltrating lymphocytes (TIL) have potential prognostic value in melanoma and have been considered for inclusion in the American Joint Committee on Cancer (AJCC) staging criteria. However, interobserver discordance continues to prevent the adoption of TIL into clinical practice. Computational image analysis offers a solution to this obstacle, representing a methodological approach for reproducibly counting TIL. We sought to evaluate the ability of a TIL-quantifying machine learning algorithm to predict survival in primary melanoma. Digitized hematoxylin and eosin (H&E) slides from prospectively enrolled patients in the NYU melanoma database were scored for % TIL using machine learning and manually graded by pathologists using Clark's model. We evaluated the association of % TIL with recurrence-free survival (RFS) and overall survival (OS) using Cox proportional hazards modeling and concordance indices. Discordance between algorithmic and manual TIL quantification was assessed with McNemar's test and visually by an attending dermatopathologist. In total, 453 primary melanoma patients were scored using machine learning. Automated % TIL scoring significantly differentiated survival using an estimated cutoff of 16.6% TIL (log-rank P < 0.001 for RFS; P = 0.002 for OS). % TIL was associated with significantly longer RFS (adjusted HR = 0.92 [0.84-1.00] per 10% increase in % TIL) and OS (adjusted HR = 0.90 [0.83-0.99] per 10% increase in % TIL). In comparison, a subset of the cohort (n = 240) was graded for TIL by melanoma pathologists. However, TIL did not associate with RFS between groups (P > 0.05) when categorized as brisk, nonbrisk, or absent. A standardized and automated % TIL scoring algorithm can improve the prognostic impact of TIL. Incorporation of quantitative TIL scoring into the AJCC staging criteria should be considered.

Surgical resection of early stage hepatocellular carcinoma improves patient survival at safety net hospitals

BACKGROUND AND OBJECTIVES

Surgical resection is indicated for hepatocellular carcinoma (HCC) patients with Child A cirrhosis. We hypothesize that surgical intervention and survival are limited by advanced HCC presentation at safety net hospitals (SNHs) versus academic medical centers (AMCs).

METHODS

Patients with HCC and Child A cirrhosis in the US Safety Net Collaborative (2012-2014) were evaluated. Demographics, clinicopathologic features, operative characteristics, and outcomes were compared between SNHs and AMCs. Liver transplantation was excluded. Kaplan-Meier and Cox proportional-hazards models were used to identify the effect of surgery on overall (OS).

RESULTS

A total of 689 Child A patients with HCC were identified. SNH patients frequently presented with T3/T4 stage (35% vs. 24%) and metastases (17% vs. 8%; p < .05). SNH patients were as likely to undergo surgery as AMC patients (17% vs. 18%); however, SNH patients were younger (56 vs. 64 years), underwent minor hepatectomy (65% vs. 38%), and frequently harbored well-differentiated tumors (23% vs. 2%; p < .05). On multivariate analysis, surgical resection and stage, but not hospital type, were associated with improved OS.

CONCLUSIONS

Although SNH patients present with advanced HCC, survival outcomes for early stage HCC are similar at SNHs and AMCs. Identifying barriers to early diagnosis at SNH may increase surgical candidacy and improve outcomes.

The Devil's in the Details: Discrepancy Between Biopsy Thickness and Final Pathology in Acral Melanoma

PURPOSE

We hypothesized that initial biopsy may understage acral lentiginous melanoma (ALM) and lead to undertreatment or incomplete staging. Understanding this possibility can potentially aid surgical planning and improve primary tumor staging.

METHODS

A retrospective review of primary ALMs treated from 2000 to 2017 in the US Melanoma Consortium database was performed. We reviewed pathology characteristics of initial biopsy, final excision specimens, surgical margins, and sentinel lymph node biopsy (SLNB).

RESULTS

We identified 418 primary ALMs (321 plantar, 34 palmar, 63 subungual) with initial biopsy and final pathology results. Median final thickness was 1.8 mm (range 0.0-19.0). There was a discrepancy between initial biopsy and final pathology thickness in 180 (43%) patients with a median difference of 1.6 mm (range 0.1-16.4). Final T category was increased in 132 patients (32%), including 47% of initially in situ, 32% of T1, 39% of T2, and 28% of T3 lesions. T category was more likely to be increased in subungual (46%) and palmar (38%) melanomas than plantar (28%, p = 0.01). Among patients upstaged to T2 or higher, 71% had ≤ 1-cm margins taken. Among the 27 patients upstaged to T1b or higher, 8 (30%) did not have a SLNB performed, resulting in incomplete initial staging.

CONCLUSIONS

In this large series of ALMs, final T category was frequently increased on final pathology. A high index of suspicion is necessary for lesions initially in situ or T1 and consideration should be given to performing additional punch biopsies, wider margin excisions, and/or SLNB.

Using digital-image analysis of tumor-infiltrating lymphocytes to predict survival outcomes in primary melanoma

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Background: Inclusion of tumor-infiltrating lymphocytes (TIL) into AJCC staging criteria has been proposed due to evidence suggesting its prognostic significance. However, subjective inter-observer discordance prevents adoption of semi-quantitative TIL grading (e.g. absent, non-brisk, brisk) into clinical practice. We hypothesize that digital-image analysis (DIA) of TIL can provide a standardized, quantitative scoring system that more accurately predicts survival compared to currently used semi-quantitative grading methods. Methods: Clinical data and tumor specimens were analyzed from prospectively enrolled primary melanoma patients in the New York University Interdisciplinary Melanoma Cooperative Group with median follow-up of 5 years. H&E-stained slides were digitized using an Aperio ScanScope at 20X magnification. QuPath software was used for automated TIL quantification. Cox regression analysis was used to assess the improved prognostic value of TIL on recurrence-free (RFS) and overall survival (OS). Patients were separated into high- and low-TIL groups using a score threshold determined by the Youden Index. Results: 453 patients (18% stage I, 42% stage II, 40% stage III) were scored using automated TIL assessment and scores were significantly correlated with better RFS and OS per 10% increase in TIL (stage adjusted hazard ratio [aHR] = 0.92 [0.84-1.00] for RFS and aHR = 0.90 [0.83-0.99] for OS). A model combining TIL score with stage increased prognostic ability for both RFS (0.68 to 0.70, P = 0.02) and OS (0.62 to 0.64, P = 0.01), as assessed by concordance indices (C-index). Kaplan-Meier curves of high- ( > 16.6%) versus low-TIL (≤16.6%) patients showed clear separation in RFS and OS (median RFS = 155 vs 48 months, P < 0.001; median OS = 155 vs 89 months, P = 0.002). For comparison, a subset of the cohort (n = 250) was semi-quantitatively graded (absent, non-brisk, brisk) by an attending melanoma pathologist; however, this did not significantly differentiate RFS between groups (P > 0.05). Conclusions: A standardized, quantitative TIL scoring system significantly improved prediction of RFS and OS in primary melanoma patients compared with semi-quantitative TIL grading. Incorporation of quantitative TIL scoring into prognostic algorithms, such as AJCC criteria, should be considered.

Development of a surgical oncology training curriculum for accreditation

In 2011, the American Board of Surgery announced a new specialty board certification for Complex General Surgical Oncology. The development of a 2-year fellowship training curriculum was based on the core values of multidisciplinary care, surgical management of oncologic disease, education in basic research and clinical trial design, community outreach, patient counseling, and leadership in oncology. This article highlights the elements necessary for developing a fellowship training program in the context of these core values.

The Landmark Series: Non-melanoma Skin Cancers

Surgery with or without radiation has always been the mainstay of treatment for patients with non-melanoma skin cancers, including basal cell carcinoma, squamous cell carcinoma, and Merkel cell carcinoma. Until recently, there were no effective systemic therapies for patients with advanced disease. This review will focus on the landmark clinical trials that led to Food and Drug Administration (FDA) approval of Vismodegib for advanced basal cell carcinoma (ERIVANCE BCC) and pembrolizumab for advanced Merkel cell carcinoma (KEYNOTE-017). These trials have not only changed the landscape for patients with metastatic disease but also notably for patients with locally advanced disease that is either unresectable or resectable with high morbidity. Additional mention is made for the clinical trial that led to FDA approval of cemiplimab for advanced cutaneous squamous cell carcinoma (EMPOWER-CSCC-1), which is already changing practice patterns, but for which longer-term data are still needed.

The solved and unresolved issues of melanoma staging: A comparison of American Joint Committee on Cancer (AJCC) 7th versus 8th edition

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Background: The recently revised (AJCC) Staging Manual, 8th edition, introduced changes including removal of mitotic index and addition of the IIID substage. There is active debate on the utility of this revision, especially, without the inclusion of a novel prognostic biomarker, during an era of major therapeutic shifts and amidst accrual of adjuvant clinical trials for high-risk resected primary melanoma. We examined whether re-staging primary melanoma patients using the new AJCC 8 system yielded improved prognostication as compared to AJCC 7. Methods: We compared the impact of changes in staging criteria in stage I-III melanoma patients who were prospectively enrolled in a NYU clinicopathological database between January 2010 and December 2016 with active protocol-driven follow up (FU). We assessed primary tumor category (T) and nodal status (N) according to both AJCC 7 and 8. Progression free survival (PFS) and overall survival (OS) curves were generated for both editions and then stratified by substage. We analyzed discordance using Cox Regression Models. Results: 1,379 patients (56% male, mean thickness 1.6, median FU 34.8 months) were included in the analyses. All but one patient remained in the same ‘major’ stage using AJCC 7 and 8 (stage I- 998; II- 224, 225; III- 157, 156) whereas 44% of stage III substage classifications were discordant comparing AJCC 7 to 8. Despite removing mitoses as a criterion for Stage I, there was no significant change between editions in PFS/OS when evaluating major and substages of stage I. Stage IIC patients had worse PFS/OS than stage IIIA patients in AJCC 8 (PFS p = 0.04, OS p = 0.02). AJCC 8, which implemented four rather than three substages, had improved PFS prognostication (c-index = 0.59 vs 0.66, p = 0.05 for AJCC 7 vs 8). Conclusions: Our results reinforce the added value of AJCC 8 compared to 7, as removing an operator dependent variable is more practical for stage I, and increased influence of thickness/ulceration and the addition of a new substage is more prognostically informative for stage III. Nevertheless, the poor prognosis of stage IIC patients, despite nodal negative disease, continues to be an unaddressed gap within our current staging framework.

Association between Ki-67 expression and clinical outcomes among patients with clinically node-negative, thick primary melanoma who underwent nodal staging

BACKGROUND

Patients with thick primary melanomas (≥4 mm) have highly variable survival outcomes. Cell proliferation marker Ki-67 has been identified as promising biomarker in thick melanoma but has not been evaluated since the wide spread adoption of sentinel lymph node biopsy. We revisit its prognostic relevance in the sentinel node era.

METHODS

We studied patients with thick (≥4 mm) primary melanoma prospectively enrolled in a clinicopathological biospecimen database from 2002 to 2015, and evaluated the prognostic value of Ki-67 expression while controlling for features included in the existing staging criteria.

RESULTS

We analyzed 68 patients who underwent lymph node sampling and who had an available tumor for Ki-67 immunohistochemical (IHC) staining. The median tumor thickness was 6.0 mm; the median follow-up was 2.6 years. In multivariable analysis including nodal status and primary tumor ulceration, Ki-67 expression was an independent predictor of worse recurrence-free survival (HR 2.19, P = 0.024) and overall survival (HR 2.49, P = 0.028). Natural log-transformed tumor thickness (ln [thickness]) was also significantly associated with worse OS (HR 2.39, P = 0.010).

CONCLUSION

We identify Ki-67 and ln (thickness) as potential biomarkers for patients with thick melanoma who have undergone nodal staging. If validated in additional studies, these biomarkers could be integrated into the staging criteria to improve risk-stratification.

Surgical clerkship or medical clerkship first: Does it make a difference?

INTRODUCTION

This study compares NBME surgical clerkship scores of students who completed their medicine clerkship before their surgical clerkship with the performance of those who had not previously completed their medical clerkship.

METHODS

The study included 815 New York University School of Medicine students from the years 2014-2018 (571 students took medicine first, while 244 took surgery first). Performance on the surgical clerkship was assessed using the NBME SHELF examination. Statistical comparisons were performed via 2-tailed, independent-samples, unequal-variance t-tests.

RESULTS

Mean NBME surgical SHELF scores of the students who had previously taken medicine were significantly higher than students who had not (mean 78.6 vs. 73.5, p < 0.001). Students who had solely medicine (as their first clerkship) before surgery also performed significantly better (mean 78.8 vs. 73.5, p < 0.001). Students who completed surgery later in the year did not perform better on the surgical SHELF, so long as both surgical clerkship cohorts had completed medicine.

CONCLUSION

Students who completed their core medical clerkship prior to their surgical clerkship scored significantly better on the NBME surgical SHELF examination.

Treatment Outcomes for Metastatic Melanoma of Unknown Primary in the New Era: A Single-Institution Study and Review of the Literature

BACKGROUND

Metastatic melanoma of unknown primary (MUP) is uncommon, biologically ill defined, and clinically understudied. MUP outcomes are seldom reported in clinical trials. In this study, we analyze responses of MUP patients treated with systemic therapy in an attempt to inform treatment guidelines for this unique population.

METHODS

New York University (NYU)'s prospective melanoma database was searched for MUP patients treated with systemic therapy. PubMed and Google Scholar were searched for MUP patients treated with immunotherapy or targeted therapy reported in the literature, and their response and survival data were compared to the MUP patient data from NYU. Both groups' response data were compared to those reported for melanoma of known primary (MKP).

RESULTS

The MUP patients treated at NYU had better outcomes on immunotherapy but worse on targeted therapy than the MUP patients in the literature. The NYU MUP patients and those in the literature had worse outcomes than the majority-MKP populations in 10 clinical trial reports.

CONCLUSIONS

Our study suggests that MUP patients might have poorer outcomes on systemic therapy as compared to MKP patients. Our cohort was small and limited data were available, highlighting the need for increased reporting of MUP outcomes and multi-institutional efforts to understand the mechanism behind the observed differences.

Outcomes in Melanoma Patients Treated with BRAF/MEK-Directed Therapy or Immune Checkpoint Inhibition Stratified by Clinical Trial versus Standard of Care

OBJECTIVES

Since 2011, metastatic melanoma treatment has evolved with commercial approval of BRAF- and MEK-targeted therapy and CTLA-4- and PD-1-blocking antibodies (immune checkpoint inhibitors, ICI). While novel therapies have demonstrated improved prognosis in clinical trials, few studies have examined the evolution of prognosis and toxicity of these drugs among an unselected population. We assess whether survival and toxicity reported in trials, which typically exclude most patients with brain metastases and poor performance status, are recapitulated within a commercial access population.

METHODS

182 patients diagnosed with stage IV melanoma from July 2006 to December 2013 and treated with BRAF- and/or MEK-targeted therapy or ICI were prospectively studied. Outcomes and clinicopathologic differences between trial and commercial cohorts were assessed.

RESULTS

Patients receiving commercial therapy (vs. on trial) had poorer prognostic features (i.e., brain metastases) and lower median overall survival (mOS) when assessed across all treatments (9.2 vs. 17.5 months, p = 0.0027). While toxicity within trial and commercial cohorts did not differ, patients who experienced toxicity had increased mOS (p < 0.001), irrespective of stratification by trial status or therapy.

CONCLUSION

Metastatic melanoma patients receiving commercial treatment may represent a different clinical population with poor prognostic features compared to trial patients. Toxicity may prognosticate treatment benefit.

Primary melanoma histologic subtype (HS) impacts melanoma specific survival (MSS) and response to systemic therapy

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Background: Unlike other solid tumors, the impact of primary HS on melanoma survival and response to systemic therapy is not well studied. Nodular melanoma (NM) has a worse prognosis than superficial spreading melanoma (SSM), which is usually attributed to thicker primary tumors. Herein, we examine the hypothesis that HS might have an impact on MSS independent of thickness and that NM and SSM exhibit different mutational landscapes that associate with response to checkpoint inhibitor immunotherapy (IT) and BRAF targeted therapy (TT) in the metastatic setting. Methods: Primary NM and SSM patients prospectively enrolled at NYU (2002 - 2016) were compared to the most recent SEER cohort (1973 - 2012) and analyzed with respect to MSS. Next-Generation Sequencing (NGS) was performed on a subset of matched tumor-germline pairs, allowing a comparison of the mutational landscape between NM and SSM. In the metastatic setting, survival analyses were used to compare outcomes and responses to treatment across HS. Results: The NYU cohort of 1,621 patients with either NM (n = 510) or SSM (n = 1,111) was representative of the analogous SEER cohort (21,339 NM, 97,169 SSM), with NM presenting as thicker, more ulcerated, and later stage (all p < 0.001). Among the NYU cohort, NM was found to have lower rates of TIL (p = 0.047), higher mitotic index (p < 0.001), and higher rates of NRAS mutation (p < 0.001). In multivariate Cox models, NM was a significant predictor of worse MSS, independent of thickness and stage (p = 0.01). NM had a significantly lower mutational burden across the exome (p < 0.001). Some of the most under-mutated genes noted in NM were NOTCH4, BCL2L12 and RPS6KA6 (all p < 0.01). Among patients treated with TT (n = 56), NM remained a significant predictor of worse MSS (p = 0.004). However, there was no difference in response to IT. Conclusions: NM and SSM show divergent mutational patterns which may contribute to their different clinical behaviors and responses to BRAF targeted therapy. More studies are needed to better understand the key molecular and cellular processes driving such differences. Integration of HS data into prospective clinical trial reporting is needed to better assess its impact on response to treatment.

Targeting EZH2 in acral lentiginous melanoma (ALM)

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Background: Efforts to identify targeted therapies that can improve treatment outcome in metastatic ALM have been unsuccessful. In a previous genomic screening, we identified copy number amplification of the histone methyltransferase EZH2 in 47% of ALM cases, a higher frequency than previously reported in cutaneous melanomas (CM) (5%). Here, we tested the hypothesis that increased EZH2 expression contributes to ALM progression and may confer selective sensitivity to EZH2 inhibition. Methods: EZH2 expression was examined by immunohistochemistry (IHC) in 51 primary (21 stage I, 13 Stage II and 17 Stage III) and 23 metastatic (11 in transit, 8 nodal and 4 visceral) ALM cases with extensive clinicopathological data and protocol-driven follow up. Colony formation and cell proliferation was assessed following treatment of ALM and CM cell lines with three EZH2 inhibitors, including GSK126, currently in clinical trials. The effect of GSK126 on H3K27me3 and downstream EZH2 targets was analyzed by western blotting. Results: EZH2 is commonly overexpressed in both primary (30/51; 65%) and metastatic (20/23; 87%) ALM cases, with a significant increase in mean IHC score between primary and metastatic tumors (1.9 vs. 2.7, respectively, p = 0.047). EZH2 expression increased in 6/10 metastatic ALM tumors compared to their matched primary tumors. ALM tumors with EZH2 gene amplification showed increased EZH2 protein expression; however more cases showed overexpression with no amplification suggesting a potential epigenetic component of EZH2 regulation. GSK126 significantly suppressed ALM colony formation at lower doses compared to CM (1 µM vs. 5 µM, respectively). EZH2 inhibition also increased expression of the downstream tumor suppressor E-cadherin in ALM but not in CM cell lines. Finally, ALM cell lines had significantly lower basal H3K27me3 levels than CM cell lines, suggesting an additional, histone methyltransferase-independent function of EZH2 in ALM. Conclusions: Our data demonstrate thatEZH2 upregulation is common in ALM, and suggest that it may play a role in ALM’s metastatic progression that requires further investigation. Selective sensitivity of ALM cell lines to EZH2 inhibitors supports the therapeutic potential of EZH2-targeted therapy in ALM.

The Expression Quantitative Trait Loci in Immune Pathways and their Effect on Cutaneous Melanoma Prognosis

PURPOSE

The identification of personalized germline markers with biologic relevance for the prediction of cutaneous melanoma prognosis is highly demanded but to date, it has been largely unsuccessful. As melanoma progression is controlled by host immunity, here we present a novel approach interrogating immunoregulatory pathways using the genome-wide maps of expression quantitative trait loci (eQTL) to reveal biologically relevant germline variants modulating cutaneous melanoma outcomes.

EXPERIMENTAL DESIGN

Using whole genome eQTL data from a healthy population, we identified 385 variants significantly impacting the expression of 268 immune-relevant genes. The 40 most significant eQTLs were tested in a prospective cohort of 1,221 patients with cutaneous melanoma for their association with overall (OS) and recurrence-free survival using Cox regression models.

RESULTS

We identified highly significant associations with better melanoma OS for rs6673928, impacting IL19 expression (HR, 0.56; 95% CI, 0.41-0.77; P = 0.0002) and rs6695772, controlling the expression of BATF3 (HR, 1.64; 95% CI, 1.19-2.24; P = 0.0019). Both associations map in the previously suspected melanoma prognostic locus at 1q32. Furthermore, we show that their combined effect on melanoma OS is substantially enhanced reaching the level of clinical applicability (HR, 1.92; 95% CI, 1.43-2.60; P = 2.38e-5).

CONCLUSIONS

Our unique approach of interrogating lymphocyte-specific eQTLs reveals novel and biologically relevant immunomodulatory eQTL predictors of cutaneous melanoma prognosis that are independent of current histopathologic markers. The significantly enhanced combined effect of identified eQTLs suggests the personalized utilization of both SNPs in a clinical setting, strongly indicating the promise of the proposed design for the discovery of prognostic or risk germline markers in other cancers. Clin Cancer Res; 22(13); 3268-80. ©2016 AACR.