Clinical features associated with transformation of cerebriform T-cell lymphoma to a large cell process.

Some patients with cerebriform T-cell lymphoma (CTCL) undergo morphologic transformation to a large cell lymphoma. From a series of 113 patients with CTCL, 22 patients were identified with transformed CTCL. Stages of involvement at diagnosis were: I (seven), II (four), III (four), IV (seven). Nine patients had transformation at the initial diagnosis while the median time from diagnosis to transformation in the other 13 patients was 16 months (range: 3 months-6 years). Thirteen had transformation extracutaneously: lymph nodes (eight), central nervous system (two), and other extranodal sites (three). T cell markers were identified in all cases; of 15 cases with complete phenotypes, there were eight T-helper, three T-suppressor, and four aberrant T phenotypes. Serology for human T-leukemia virus-I (HTLV-I) was negative in eight patients tested. Median survival from diagnosis was 27 months compared to 53 months in 53 patients without transformation (p = 0.003). Despite combination chemotherapy in 12 patients following transformation, median survival after transformation was 12 months and only 7 months with extracutaneous disease. The likelihood of transformation could not be predicted by the initial histology, immunophenotype, or stage of disease.