Survival Benefit of Guideline-Concordant Postoperative Radiation for Local Merkel Cell Carcinoma.

BACKGROUND: Postoperative radiation therapy (RT) for early-stage Merkel Cell Carcinoma (MCC) decreases the risk of locoregional recurrence and improve overall survival. However, concordance with RT guidelines is unknown. MATERIALS AND METHODS: The National Cancer Database was queried for stage I/II MCC patients receiving surgical intervention from 2006-2017. The cohort was stratified by patients who had and did not have indication(s) for adjuvant RT of the primary tumor site based on National Comprehensive Cancer Network guidelines. We captured the use of RT, patient demographics, socioeconomic characteristics, and clinical characteristics. Logistic regression, Kaplan-Meier method, and propensity score weighted Cox proportional hazards model examined associations and survival benefits of RT. RESULTS: 2,330 stage I/II MCC patients underwent surgical intervention. 1,858 (79.7%) met National Comprehensive Cancer Network criteria for RT of the primary tumor site, of which 1,062 (57.2%) received RT. 472 (20.3%) did not meet criteria for RT, of which 203 (43.0%) received RT. Five-year overall survival advantage was identified for patients who received RT when it was indicated (P < 0.003). There was no evidence of overall survival advantage when patients received guideline-discordant RT (P = 0.478). CONCLUSIONS: Surgical resection with adjuvant RT of the primary tumor site has an overall survival benefit for local MCC when patients meet criteria for RT. This study found a group who received guideline-discordant RT with no survival advantage. Further investigation is warranted to identify the socio-demographic and oncologic reasons for guideline discordance in the treatment of MCC for both under- and over-treatment.

Resection Margins in Merkel Cell Carcinoma: Is a 1-cm Margin Wide Enough?

BACKGROUND: Guidelines regarding specific resection margins for primary Merkel cell carcinoma (MCC) are not well established. The current National Comprehensive Cancer Network (NCCN) guidelines recommend 1- to 2-cm resection margins. This study aimed to determine the impact of margin width on local recurrence (LR), disease-specific survival (DSS), overall survival (OS), and type of wound closure. METHODS: All patients who underwent resection of primary MCC at a single institution from 2000 to 2015 were reviewed. Patient demographics, clinicopathologic characteristics, treatments, and outcomes were reviewed. RESULTS: A total of 240 patients underwent resection of primary MCC with resection margin width identified in the operative report. The median age was 76 years, and 65.8% of the patients were men. Of the 240 patients, 85 (35.4%) had head and neck primaries, 140 (58.3%) had extremity primaries, and 15 (6.3%) had trunk primaries. In terms of margins, 69 patients (28.8%) had a margin of 1 cm, 36 patients (15%) had a margin of 1.1-1.9 cm, and 135 patients (56.2%) had a margin of 2 cm or more. The median follow-up period was 21 months. The LR rate was 2.9% for a margin of 1 cm, 2.8% for a margin of 1.1-1.9 cm, and 5.2% for a margin of 2 cm or more (p = 0.80). The 5-year OS was 63.6% for a margin of 1 cm, 59.7% for a margin of 1.1-1.9, and 70.7% for a margin of 2 cm or more (p = 0.66). The 5-year DSS was 80.3% for a margin of 1 cm, 66.2% for a margin of 1.1-1.9 cm, and 91.8% for a margin of 2 cm or more (p = 0.28). For wound closure, 43.5, 50, and 65.9% of the patients respectively required a flap or graft with a margin of 1, 1.1-1.9, and 2 cm or more (p = 0.006). CONCLUSIONS: A 1-cm resection margins did not increase the risk of LR. Margin width did not make a significant difference in DSS or OS. Larger resection margins increase the need for a graft or flap closure.

Factors associated with advanced-stage Merkel cell carcinoma at initial diagnosis and the use of radiation therapy: Results from the National Cancer Database.

BACKGROUND: The stage of disease at initial diagnosis and the use of radiation therapy (RT) are important determinants of survival in patients with Merkel cell carcinoma (MCC). OBJECTIVE: To define factors that are associated with advanced-stage MCC at the time of initial diagnosis and the use of RT. METHODS: Cross-sectional, retrospective analysis of patients with MCC registered in the National Cancer Database during the period from 2004 to 2013. RESULTS: A total of 11,917 patients were identified; 3152 and 4586 patients were excluded from the staging and RT analyses, respectively, because of lack of available data. African American ethnicity (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.06-2.10; P = .023), lack of medical insurance (OR, 2.15; 95% CI, 1.40-3.30; P < .001), Charlson-Deyo comorbidity score of at least 1 (OR, 1.21; 95% CI, 1.09-1.34; P < .001), residence more than 26 miles from a treatment facility (OR, 1.18; 95% CI, 1.03-1.35; P = .015), tumor located on the lower limb/hip (OR, 1.59; 95% CI, 1.42-1.78; P < .001) or trunk (OR, 2.05; 95% CI, 1.81-2.33; P < .001), and poorly (OR, 2.57; 95% CI, 1.13-5.82; P = .024) or undifferentiated (OR, 3.11; 95% CI, 1.36-7.15; P = .007) tumor histology predicted advanced-stage MCC at the time of initial diagnosis. The use of RT was associated with Native American ethnicity (OR, 5.04; 95% CI, 1.10-22.99; P = .037), tumor size between 1.5 and 2.7 cm (OR, 1.27; 95% CI, 1.10-1.47; P = .001), electing not to have surgery (OR, 2.77; 95% CI, 1.90-4.03; P < .001), positive postsurgical margins (OR, 1.39; 95% CI, 1.18-1.63; P < .001), and receiving treatment at a comprehensive cancer program (OR, 1.25; 95% CI, 1.03-1.50; P = .020). LIMITATIONS: Retrospective design limits generalizability of the results, and precise details of RT regimens utilized were not available. CONCLUSIONS: A number of factors are associated with advanced-stage MCC at initial diagnosis and the use of RT. Health care models should account for these factors, and efforts should be directed toward improving those that are modifiable.

Nonmelanoma skin cancer.

This article provides readers with a comprehensive review of the evaluation and management of nonmelanoma skin cancers. Treatment recommendations are heavily based on the most recent guidelines from the National Comprehensive Cancer Network. Merkel cell carcinoma and dermatofibrosarcoma protuberans are also discussed. After reviewing this article, readers should be equipped with a better understanding of these entities and the current recommendations for their management.