MALIGNANT MELANOMAS WITH HISTOLOGIC DIAMETERS LESS THAN 6-MM

Background: Malignant melanomas (MMs) with a small diameter (< 6 mm) are rarely removed surgically; therefore there is a need for more data to characterize them. Objective: The purpose of this study was to further elucidate the clinical and histopathologic features of small melanomas. Methods: The greatest diameters of 112 consecutively submitted MMs were measured histologically. Those lesions with diameters of less than 6 mm were further studied clinically and histopathologically. Results: Four MMs (3.5%) were found to have small histologic diameters. Their clinical features differed from the classic clinical ABCD's, although their histopathologic features resembled those of large MMs. Their depth of dermal invasion was relatively superficial, and their clinical outcome was favorable. Conclusion: Histopathologically, small MMs tend to resemble large MMs, but clinically they may require other diagnostic criteria. Because they tend to show a relatively superficial depth of invasion, their increased recognition and removal may have an impact on overall mortality from MM.