Hepatic involvement by T-cell neoplasms: a clinicopathologic study of 40 cases.

Hepatic involvement by a T-cell neoplasm is rare and often challenging to diagnose in liver biopsies. We collected 40 cases of T-cell neoplasms diagnosed in the liver from five large academic institutions to assess the clinicopathologic features. The patients included 11 women and 29 men, with a median age of 54 (range: 2-75) years and a high mortality rate (31/37, 83.8%). Fourteen (35%) patients were diagnosed with hepatosplenic T-cell lymphoma (HSTCL), 13 (32.5%) peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), and 13 (32.5%) other types of T-cell neoplasms. Patients with HSTCL were much younger and had worse survival than PTCL-NOS and other T-cell neoplasms (P < 0.05). On imaging studies, 20 cases (50%) showed abnormalities, including 10 with mass lesions that correlated with normal or cholestatic pattern enzyme elevation. Histomorphological analysis revealed four main patterns; with the exception of mass forming lesions (pattern 4; n = 8), cases with sinusoidal predominant (pattern 1; n = 12), portal predominant with sinusoidal infiltrates (pattern 2; n = 13) or lobular aggregates (pattern 3; n = 5) demonstrated small to medium lymphocytes resembling a reactive/inflammatory process. In addition, we described two cases of T-cell large granular lymphocytic leukemia that mimicked HSTCL, and a case of aggressive post-transplant lymphoproliferative disorder that developed after chronic Epstein-barr virus (EBV) infection, suggesting the importance of EBV testing in some lymphoma cases. As the largest cohort of T-cell neoplasms in liver, our study provides critical data on disease frequency, distribution, and clinicopathologic features that are essential for accurate diagnosis.