Cutaneous CD30-positive T-cell lymphoproliferative disorders— clinical and histopathologic features, differential diagnosis, and treatment
Cutaneous CD30+ T-cell lymphoproliferative disorders (CD30+ LPD) are the second most common form of cutaneous T-cell lymphoma. CD30+ LPD include lymphomatoid papulosis, primary cutaneous anaplastic large-cell lymphoma, and borderline lesions. Despite expression of CD30 by the neoplastic cells as the hallmark of these disorders, they differ in their clinical presentation and histological features as well as the course, the prognosis, and consecutively in the treatment. Diagnosis of CD30+ LPD and distinction from the broad spectrum of differential diagnoses essentially depends on clinicopathologic correlation as well as the results of staging examinations. Although the histological findings indicate a high-grade lymphoma, CD30+ LPD in most cases have a favorable prognosis. Recent advances in targeted therapy have led to new therapeutic approaches to CD30+ LPDs. This review describes the clinicopathologic features of CD30+ LPDs, their differential diagnoses, the treatment, and the role ofCD30 as a diagnostic marker and therapeutic target.