[Cutaneous anaplastic large cell lymphoma: clinicopathologic, immunohistochemical and prognostic study of 44 cases].

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

Methods: Histopathologic evaluation and immunohistochemical study by Envision method were carried out in 44 archival cases of CALCL. The clinical information and follow-up data were analyzed.

Results: The patients presented with skin nodules, masses or plaques, sometimes associated with ulceration. The commonest sites of involvement were the extremities. Follow-up data were available in 39 patients. The overall survival rate was 87.2% (34/39). Disease relapses were detected in 46.2% (18/39) of the patients. Statistical analysis indicated that patients older than 50 years of age or with no less than two involved anatomic sites were more likely to have disease relapses (P < 0.05). Histologically, 31 cases were classified as common variant, 6 cases as small cell variant and 7 cases as neutrophil/eosinophil-rich variant. Immunohistochemical study showed that the rates of expression of CD30, CD45, CD45RO, CD43, CD3, cytotoxic protein and epithelial membrane antigen were 100% (44/44), 91.2% (31/34), 82.6% (19/23), 94.7% (18/19), 70.0% (28/40), 73.3% (22/30) and 31.8% (7/22), respectively. The CD4(+)/CD8(-), CD4(-)/CD8(+) and CD4(-)/CD8(-) immunophenotypes were found in 58.3% (21/36), 22.2% (8/36) and 19.4% (7/36) of the CALCL cases, respectively. Only one case (3.7%) expressed CD56.

Conclusions: CALCL is a form of low-grade primary cutaneous T-cell lymphoma with a wide spectrum of clinicopathologic pattern. Special variants of CALCL should not be confused with other types of cutaneous lymphomas and inflammatory lesions. CALCL patients older than 50 years of age or with no less than two involved anatomic sites are more likely to have disease relapses.