[Pathological and clinical correlations in primary cutaneous B-cell lymphomas: a series of 44 cases]

histological and clinical relationship study of 44 cases of primary cutaneous B cell lymphoma, classified according to WHO classification.

histological, immunological and molecular analysis was correlated with clinical data.

33 cases (75%) were marginal zone B-cell lymphomas (MZL), with head and trunk predominance (median age = 54 years). Relapses in other mucosa-related sites occurred in 3 patients. Histological transformation implied a more aggressive treatment in 3 cases. A favorable outcome was observed in most cases. 9 (20%) diffuse large B-cell lymphomas (DLBCL) appeared as a unique nodule, with female predominance (median age = 74 years) and 4 lymphoma-related deaths which seemed age-related (> 70 years) with only one lower limb localization. Histological aggressive features were present in 3 patients with a fatal outcome. 2 (5%) WHO grade 3 follicular lymphomas (FL) had an heterogeneous phenotype, with head localization, cutaneous relapses and good outcome.

MZL, the predominant type, has a good prognosis, although transformation can occur, needing a more aggressive treatment. DLBCL, observed in older patients, has clinical and histological prognostic factors identical to extra-cutaneous lymphomas. FL appears rare and has an heterogeneous phenotype. Relationships with its nodal counterpart remains unclear.