mart-1-antigen and Precancerous-Conditions

The efficacy of Mohs micrographic surgery (MMS) for atypical intraepidermal melanocytic proliferation (AIMP) is unknown.. To ascertain the frequency of diagnostic change to melanoma (upstaging) and the frequency of local recurrence after MMS for AIMP. A secondary outcome was the frequency of subclinical spread (defined as the requirement for >1 stage of MMS to achieve tumor-free margins).. Retrospective, cross-sectional study of 223 AIMP (with 92.4% located on the head, neck, hand, foot, or pretibial leg) patients treated with MMS with melanoma antigen recognized by T cells 1 (MART-1) immunostaining.. Upstaging to unequivocal melanoma in situ or invasive melanoma was identified in 18.8% (42/223) of all AIMP patients. The local recurrence rate was 0% (0/223) with a mean follow-up time of 2.7 years (998 days). Subclinical spread was present in 23.8% (53/223) of AIMP patients.. Single site, retrospective design, observational study, lack of objective criteria to diagnose AIMP.. MMS with MART-1 immunostaining achieves excellent local control of specialty site AIMP and permits definitive removal of subclinical spread before reconstruction. The central debulking excision should be evaluated with formalin-fixed paraffin-embedded section staining, since a significant percentage of AIMP are reclassified as melanoma in situ or invasive melanoma.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antigens, Neoplasm; Biopsy; Cross-Sectional Studies; Diagnostic Errors; Epidermis; Female; Follow-Up Studies; Humans; Hutchinson's Melanotic Freckle; Male; MART-1 Antigen; Melanocytes; Melanoma; Middle Aged; Mohs Surgery; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Neoplasm Staging; Precancerous Conditions; Retrospective Studies; Skin Neoplasms; T-Lymphocytes; Young Adult

Topics: Antigens, Neoplasm; Biomarkers, Tumor; Fluorescent Antibody Technique, Indirect; Humans; Immunoenzyme Techniques; Lymphocytes, Tumor-Infiltrating; MART-1 Antigen; Melanocytes; Melanoma; Neoplasm Proteins; Precancerous Conditions; Skin; Skin Neoplasms

Melanocytic lesions with lichenoid regression may mimic a benign lichenoid keratosis (BLK) histologically. A total of 336 BLKs were reviewed and deeper sections obtained to determine the frequency of this phenomenon. Two cases (0.6%) showed at least 1 melanocytic nest or junctional multinucleated melanocyte (starburst melanocyte) on deeper sections confirmed by MART-1 immunostaining. Both of these cases demonstrated solar elastosis, and 1 case had an effaced rete ridge pattern. Not included in the histological study are 5 additional cases in which the initial slide showed only lichenoid dermatitis, but deeper sections obtained before to the initial sign-out revealed a melanocytic proliferation. These 5 cases would have been signed out as "consistent with BLK" if deeper sections had not been obtained. Fluorescent in situ hybridization (FISH) was performed on 3 cases; in each case, the melanocytes demonstrated a loss of chromosome 9p21 DNA copy number. The finding of nests of genetically altered melanocytes on severely sun-damaged skin strongly suggests that these cases represent lichenoid regression of melanoma in situ. Pathologists should approach a diagnosis of BLK cautiously in the setting of severely sun-damaged skin.

Topics: Aged; Antigens, Neoplasm; Carcinoma in Situ; Chromosomes, Human, Pair 9; Diagnosis, Differential; DNA; Gene Dosage; Giant Cells; Humans; Hyperplasia; In Situ Hybridization, Fluorescence; Lichen Planus; MART-1 Antigen; Melanocytes; Melanosis; Middle Aged; Neoplasm Proteins; Precancerous Conditions; Skin Neoplasms; Sunlight