Cynthia M Magro1, Ronnie M Abraham2, Ruifeng Guo3, Shibo Li4, Xuan Wang1, Steven Proper5, A Neil Crowson6, Martin Mihm7. 1. Department of Pathology and Laboratory Medicine, Room F-309, 1300 York Avenue, Weill Medical College of Cornell University, New York, NY, USA. 2. Department of Pathology and Laboratory Medicine, Room F-309, 1300 York Avenue, Weill Medical College of Cornell University, New York, NY, USA, Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, USA. 3. Department of Pathology. 4. Genetics Laboratory, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, USA. 5. Center for Dermatology and Skin Surgery, Tampa, FL, USA. 6. Regional Medical Laboratories, Tulsa, OK, USA. 7. Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Abstract
BACKGROUND: Deep penetrating nevi (DPN) are a relatively uncommon subtype of melanocytic nevi. A small subset of these lesions exhibit atypical features (cytologic and architectural atypia, mitotic activity) seen in melanoma. These lesions we term the deep penetrating nevus-like borderline tumor. Unequivocal melanomas can show overlapping morphologic features of DPN, which have been termed plexiform melanomas. PATIENTS AND METHODS: 40 cases of DPN-like borderline tumor were identified along with 6 cases of plexiform melanoma. Clinical follow up was obtained, along with cytogenetic analysis in the form of fluorescent in situ hybridization (FISH) and/or comparative genomic hybridization (CGH). RESULTS: The DPN-like borderline tumor cases included 24 females and 16 males. Of sentinel lymph node biopsies performed, 1/3 of cases showed lymph node involvement. All patients where an aggressive clinical approach was adopted remain free of disease. All 6 DPN-like borderline tumor cases tested by CGH showed normal cytogenetics, as did 7 of 9 cases tested by FISH. Of the plexiform melanomas, 4/6 patients died of disease. In 3 cases there was morphologic progression from a DPN-like borderline tumor to overt melanoma. In one case of progression, cytogenetics was normal in the DPN-like borderline tumor and then abnormal in the progressed melanoma. CONCLUSION: DPN-like borderline tumors are melanocytic tumors associated with a high incidence of regional lymph node disease and exhibiting the potential for melanoma progression despite a normal cytogenetic profile. Patients with these lesions should be aggressively managed, with at least complete re-excision and consideration of sentinel node biopsy, regardless of cytogenetic data.
BACKGROUND: Deep penetrating nevi (DPN) are a relatively uncommon subtype of melanocytic nevi. A small subset of these lesions exhibit atypical features (cytologic and architectural atypia, mitotic activity) seen in melanoma. These lesions we term the deep penetrating nevus-like borderline tumor. Unequivocal melanomas can show overlapping morphologic features of DPN, which have been termed plexiform melanomas. PATIENTS AND METHODS: 40 cases of DPN-like borderline tumor were identified along with 6 cases of plexiform melanoma. Clinical follow up was obtained, along with cytogenetic analysis in the form of fluorescent in situ hybridization (FISH) and/or comparative genomic hybridization (CGH). RESULTS: The DPN-like borderline tumor cases included 24 females and 16 males. Of sentinel lymph node biopsies performed, 1/3 of cases showed lymph node involvement. All patients where an aggressive clinical approach was adopted remain free of disease. All 6 DPN-like borderline tumor cases tested by CGH showed normal cytogenetics, as did 7 of 9 cases tested by FISH. Of the plexiform melanomas, 4/6 patients died of disease. In 3 cases there was morphologic progression from a DPN-like borderline tumor to overt melanoma. In one case of progression, cytogenetics was normal in the DPN-like borderline tumor and then abnormal in the progressed melanoma. CONCLUSION: DPN-like borderline tumors are melanocytic tumors associated with a high incidence of regional lymph node disease and exhibiting the potential for melanoma progression despite a normal cytogenetic profile. Patients with these lesions should be aggressively managed, with at least complete re-excision and consideration of sentinel node biopsy, regardless of cytogenetic data.
Entities:
Keywords:
ambiguous melanocytic tumor; borderline melanocytic tumor; deep penetrating nevus; deep penetrating nevus-like borderline tumor; melanocytic tumor of uncertain malignant potential