Desmoplastic Melanoma: A Comprehensive Analysis of the NCDB Between the Years 2004-2015
Maria T. Huayllani, MD1, David J. Restrepo, MD1, Daniel Boczar, MD1, Andrea Sisti, MD1, Jeremie D. Oliver, BS, BA2, Sanjay P. Bagaria, MD1, Emmanuel M. Gabriel, MD, PhD1, Brian D. Rinker, MD1, Antonio Jorge Forte, MD, PhD1.
1Mayo Clinic, Jacksonville, FL, USA, 2Mayo Clinic, Rochester, MN, USA.
PURPOSE: Desmoplastic melanoma (DM) is a rare variant of melanoma. The diagnosis and management are challenging as it clinically presents as amelanotic nodules or plaques, or ill-defined scar lesions that are not similar to other common types of melanoma. We present a unique and comprehensive study reporting on demographics and disease characteristics in the US population in order to contribute to the current knowledge and better awareness of this rare disease.
METHODS: We performed a retrospective cohort study to identify demographics of desmoplastic melanoma patients diagnosed from 2004 to 2015 by querying the National Cancer Database (NCDB). Additionally, we compared the disease characteristics of desmoplastic melanoma with the common malignant melanoma, excluding all unknown values. Statistical analysis was performed using univariate and multivariate regression model.
RESULTS: 5895 patients diagnosed withdesmoplastic melanoma and 292 939 patients with common malignant melanoma met inclusion criteria. Mean age at diagnosis for DM was 68.3 years-old. Most of the population was white (97.91%), male (67.53%), and between 61 to 80 years old (50.64%). The most common location wasthe scalp and neck (24.17%). Surgery was indicated in most of the cases (98.35%), without receivingany radiation therapy (84.21%). Distant metastases were uncommon: lungs (n=46; 78%), bones (n=11; 0.19%), liver (10; 0.17%) and brains (n=8; 0.14%). When disease characteristics were compared between desmoplastic melanoma and common malignant melanoma, patients with DM tend to present an older age at diagnosis (15.5% vs8.5%; aOR:3.57; IC: 2.59-4.92), a more advance stage at diagnosis (63.9% vs25%; aOR:13.9; CI: 3.43-57.26), a Breslow depth greater than 4 mm (39.7% vs11.8%; aOR:7.63; CI: 5.95-9.79); as well as radiation therapy was more frequently required (14.2% vs2.1%; aOR:6.08; CI: 4.81-7.67) . On the other hand, desmoplastic melanoma lesions have less probability to present ulceration (15.2% vs 24.6%; aOR:0.28; CI: 0.24-0.33), regression (4.9% vs 11.9%; aOR:0.45; CI: 0.35-0.58), have more than one mitosis per mm2on histology (68.4% vs 76.1%, aOR:0.35; CI: 0.30-0.40), have lymph nodes involvement (6.9 % vs 19.1%; aOR:0.32; CI: 0.21-0.48)) or metastasis to the brain at diagnosis (0.06% vs 0.13% ; aOR: 0.11; CI: 0.01-0.99) when were compared with people with common malignant melanoma (p <0.05).
CONCLUSION: This study underscores important differences between desmoplastic melanoma and the common malignant melanoma. Specific demographic factors and disease characteristics should be taken into consideration for early diagnosis and treatment in order to avoid progression of this benign-looking but deadly disease.
Back to 2019 Posters