Mediastinal Anaplastic Large-Cell Lymphoma
Ki-1 lymphoma; Ki-1-positive large-cell lymphoma; Lymphoma; Large-cell anaplastic, CD30-positive; Malignant histiocytosis
Anaplastic large-cell lymphoma (ALCL) is a mature T-cell neoplasm characterized by strong CD30 expression and the presence of “hallmark cells,” which are usually large atypical cells with kidney- or horseshoe-shaped nuclei, abundant cytoplasm, and characteristic perinuclear (Golgi) clearing. ALCL also tends to have a cohesive growth pattern and a propensity for lymph node sinusoidal distribution. The current 2008 WHO classification of hematolymphoid neoplasms distinguishes an ALK-positive and an ALK-negative variant of ALCL. ALK-positive ALCL is characterized by translocations involving the ALK gene, resulting in overexpression of novel chimeric ALK proteins. ALK-negative ALCL is morphologically and immunophenotypically similar to ALK-positive ALCL but lacks ALK gene rearrangements and ALK protein expression. It is a provisional entity in the...
References and Further Reading
- Savage, K. J., Harris, N. L., Vose, J. M., Ullrich, F., Jaffe, E. S., Connors, J. M., et al. (2008). ALK- anaplastic large-cell lymphoma is clinically and immunophenotypically different from both ALK + ALCL and peripheral T-cell lymphoma, not otherwise specified: Report from the International Peripheral T-Cell Lymphoma Project. Blood, 111(12), 5496–5504.PubMedCrossRefGoogle Scholar