Primary cutaneous malignant melanoma and its precursor lesions: diagnostic and therapeutic overview.

During the past few decades, scientific data relating to melanoma have flourished. New information regarding acquired nevi, dysplastic nevi (atypical nevi), and congenital nevi has given us a better understanding of these precursor lesions and their relationships to malignant melanoma. The roles of laboratory testing, photography, and newer diagnostic tools (eg, epiluminescence) to evaluate patients for melanoma or precursor lesions have fallen under close scrutiny. Traditional surgical therapeutic interventions continue to be replaced by less aggressive protocols based on prospective randomized studies. Many new interventions such as sentinel lymph node procedures are currently being evaluated at research/referral centers around the world. We present clinicians with an evidence-based summary of the current literature with regard to primary cutaneous melanoma, its diagnosis, precursor lesions, and therapy.

Natural killer/natural killer-like T-cell lymphoma, CD56+, presenting in the skin: an increasingly recognized entity with an aggressive course.

PURPOSE: To describe and identify the clinical and pathologic features of prognostic significance for natural killer (NK) and NK-like T-cell (NK/T-cell) lymphoma presenting in the skin. PATIENTS AND METHODS: This study was a retrospective review of 30 patients with CD56+ lymphomas initially presenting with cutaneous lesions, with analysis of clinical and histopathologic parameters. RESULTS: The median survival for all patients was 15 months. Those with extracutaneous manifestations at presentation (11 patients) had a shorter median survival of 7.6 months as compared with those without extracutaneous involvement (17 patients), who had a more favorable median survival of 44.9 months (P =.0001). Age, gender, extent of cutaneous involvement, and initial response to therapy had no statistically significant effect on survival. Seven patients (24%) had detectable Epstein-Barr virus (EBV) within neoplastic cells. The patients with tumor cells that coexpress CD30 (seven patients) have not yet reached a median survival after 35 months of follow-up as compared with those with CD30- tumor cells (20 patients), who had a median survival of 9.6 months (P <.02). Routine histopathologic characteristics had no prognostic significance nor did the presence of CD3epsilon, EBV, or multidrug resistance. CONCLUSION: NK/T-cell lymphoma is an aggressive neoplasm; however, a subset with a more favorable outcome is identified in this study. The presence of extracutaneous disease at presentation is the most important clinical variable and portends a poor prognosis. The extent of initial skin involvement does not reliably predict outcome. Patients from the United States with NK/T-cell lymphoma presenting in the skin have a low incidence of demonstrable EBV in their tumor cells. Patients with coexpression of CD30 in CD56 lymphomas tend to have a more favorable outcome.

Prediction of sentinel lymph node micrometastasis by histological features in primary cutaneous malignant melanoma.

OBJECTIVE: To develop a prognostic model, based on clinical and pathological data, to estimate the probability of micrometastasis in the sentinel lymph node in patients with malignant melanoma. DESIGN: Retrospective analytical study. SETTING: University medical center. PATIENTS: Two hundred fifteen patients with American Joint Committee on Cancer stages I and II cutaneous malignant melanoma underwent sentinel lymph node biopsy. MEASUREMENTS: Presence of microscopic melanoma in the sentinel lymph node(s). Clinical attributes recorded included age, sex, and location of the primary melanoma. Pathological attributes recorded before lymph node evaluation included ulceration, microsatellites, angiolymphatic invasion, mitotic rate, tumor infiltrating lymphocytes, and regression. RESULTS: Forty-six patients (21.4%) overall had a positive sentinel lymph node. Patients with tumor thickness ranging from 3.0 to 3.9 mm had the highest incidence (50%) of nodal involvement, followed by those with tumors 4.0 to 4.9 mm thick (41%). Patients with melanomas measuring greater than 4.9 mm thick and those between 1.0 and 2.9 mm had a similar rate of nodal involvement (16%-17%). Clinical characteristics had minimal correlation with nodal status in multivariate analysis. The total number of histological high-risk features was significantly correlated with sentinel lymph node involvement. Important pathological risk factors included ulceration, high mitotic rate, angiolymphatic invasion, and microsatellites. Patients with tumor thickness greater than 1.0 mm but lacking these features had a 14% risk of occult metastases. CONCLUSION: Among patients with clinically node-negative primary melanoma, the presence of 1 or more high-risk histological features significantly increases the incidence of microscopic nodal involvement and can be used to predict the likelihood of a positive sentinel lymph node biopsy.