Histopathological analysis of the progression pattern of subungual melanoma: late tendency of dermal invasion in the nail matrix area

Nail apparatus melanoma: A comparative, clinicoprognostic study of the initial clinical and morphological characteristics of 49 patients

“…According to a recent pathologic analysis, dermal invasion into the nail apparatus by melanoma in the nail matrix tends to occur later than other areas of the nail unit. 27 A nail apparatus melanoma that began in the hyponychium and subsequently developed into a longitudinal melanonychia has been reported previously. 28 Nail apparatus melanoma that began as nonmelanonychia lesions could originate from the nail bed or periungual component, presenting nail bed mass or periungual pigmentation.…”

In situ nail unit melanoma: epidemiological and clinic‐pathologic features with conservative treatment and long‐term follow‐up

“…The skin of the proximal and lateral nail folds is more distant, following the non-visible parts of the folds. In addition, Shin et al 23 suggest that dermal invasion in the nail matrix occurs during the late stages of subungual melanoma progression, suggesting that conservative surgical treatment for in situ NUM is safe. We do not have enough information to advise spontaneous healing instead of graft.…”

Acral Lentiginous Melanoma, Indolent Subtype Diagnosed by En Bloc Excision: A Case Report

“…In this regard, Izumi et al11 proposed a pathological characteristic that the tumor cells are more noticeable in the hyponychium than in the nail bed or matrix. In addition, Shin et al1213 revealed that the nail matrix is more resistant to invasion, due to the presence of the onychodermis and the upward growth of the nail matrix. Based on these investigations, a longitudinal incisional biopsy that is inclusive all parts of the nail unit should be preferred over punch matrix biopsy, in order to avoid underdiagnosis1113.…”

“…In addition, Shin et al1213 revealed that the nail matrix is more resistant to invasion, due to the presence of the onychodermis and the upward growth of the nail matrix. Based on these investigations, a longitudinal incisional biopsy that is inclusive all parts of the nail unit should be preferred over punch matrix biopsy, in order to avoid underdiagnosis1113. In this case, the incisional biopsy specimen does not appear to include the most severe area, which might have resulted in the lack of evidence of malignancy on histopathological examination.…”