[Primary cutaneous anaplastic large cell lymphoma: a clinicopathologic analysis of 8 cases].

Objective: To study the clinicopathologic features, immunophenotype and prognosis of primary cutaneous anaplastic large cell lymphoma (C-ALCL).

Methods: Eight cases of C-ALCL were enrolled into the study. The clinicopathologic features, immunohistochemical findings and results of in-situ hybridization for EBER 1/2 were analyzed.

Results: Three of the 8 patients were males and 5 were females. The median age was 49.5 years. C-ALCL often presented with solitary skin nodule, without systemic symptoms. Histologically, the lymphoma cells infiltrated the dermis and subcutis in a sheet-like pattern. They were of large size and showed conspicuous nuclear atypia. Immunohistochemical study showed that more than 75% of the lymphoma cells were positive for CD30. All cases expressed one to three T cell markers (CD3, CD5 or CD45RO) and cytotoxic granule-associated antigens (TIA-1, granzyme B or perforin). The staining for leukocyte common antigen was positive in all cases, while the expression of CD5, CD8, ALK-1 and epithelial membrane antigen was noted in 5, 1, 1 and 3 cases, respectively. The staining for CD15, CD20, CK and HMB45 was negative. In-situ hybridization for EBER 1/2 was also negative in all the cases studied. Follow-up information was available in 6 patients. Five of them were still alive and 1 died of unclear cause.

Conclusions: C-ALCL has distinctive clinicopathologic and immunophenotypic features. It is not Epstein-Barr virus-related and often carries a favorable prognosis.