Ritva Vyas1, Jesse J Keller1, Kord Honda1, Kevin D Cooper1, Meg R Gerstenblith2. 1. Department of Dermatology, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio. 2. Department of Dermatology, University Hospitals Case Medical Center, Case Western Reserve University School of Medicine, Cleveland, Ohio. Electronic address: Meg.Gerstenblith@uhhospitals.org.
Abstract
BACKGROUND: Animal-type melanoma is a rare subtype of melanoma with heavily pigmented dermal epithelioid and spindled melanocytes. Its classification as a subtype of melanoma versus a borderline melanocytic tumor is debated. OBJECTIVES: Our primary objective was to characterize the demographics, clinical presentation, histopathology, management, and outcomes of patients with animal-type melanoma. METHODS: We performed a systematic review and meta-analysis of the English-language literature on animal-type melanoma. RESULTS: We identified 190 cases of animal-type melanoma. They occurred equally in men and women, with Caucasians (53.7%) most commonly affected. The median Breslow depth was 3.8 mm; ulceration was reported present in 15.8%; and dermal mitoses greater than or equal to 1/mm(2) was reported in 27.4%. The most common initial management was wide local excision with sentinel lymph node biopsy (55.7%). In all, 78 patients underwent sentinel lymph node biopsy with 41.0% positivity rate. A total of 32 patients underwent completion lymph node dissection with 34.4% positivity rate. Locoregional recurrence was reported in 15 patients, recurrence with distant metastases in 6 patients, and death in 5 patients. LIMITATIONS: Data were obtained from small studies with limited follow-up. There is no universally accepted definition of animal-type melanoma. CONCLUSION: Prospective studies with complete staging information and molecular profiling may allow further characterization of this tumor.
BACKGROUND: Animal-type melanoma is a rare subtype of melanoma with heavily pigmented dermal epithelioid and spindled melanocytes. Its classification as a subtype of melanoma versus a borderline melanocytic tumor is debated. OBJECTIVES: Our primary objective was to characterize the demographics, clinical presentation, histopathology, management, and outcomes of patients with animal-type melanoma. METHODS: We performed a systematic review and meta-analysis of the English-language literature on animal-type melanoma. RESULTS: We identified 190 cases of animal-type melanoma. They occurred equally in men and women, with Caucasians (53.7%) most commonly affected. The median Breslow depth was 3.8 mm; ulceration was reported present in 15.8%; and dermal mitoses greater than or equal to 1/mm(2) was reported in 27.4%. The most common initial management was wide local excision with sentinel lymph node biopsy (55.7%). In all, 78 patients underwent sentinel lymph node biopsy with 41.0% positivity rate. A total of 32 patients underwent completion lymph node dissection with 34.4% positivity rate. Locoregional recurrence was reported in 15 patients, recurrence with distant metastases in 6 patients, and death in 5 patients. LIMITATIONS: Data were obtained from small studies with limited follow-up. There is no universally accepted definition of animal-type melanoma. CONCLUSION: Prospective studies with complete staging information and molecular profiling may allow further characterization of this tumor.