Discussion
Peripheral TCL (PTCL) are a rare, typically extranodal group of malignancies. They are aggressive and generally have a poor outcome, with most patients dying of lymphoma within 2 years. 3 T-cell lymphomas most commonly express the γ-δ TCR. About 2% to 4% of TCLs express the γ-δ TCR. 4 In 2008, the World Health Organization recognized 2 distinct GDTCL subgroups: hepatosplenic GDTCL (HSGDTCL) and primary cutaneous GDTCL. 5 As the patient presented with hepatic involvement, this discussion focused on HSGDTCL.
Hepatosplenic GDTCL are rare types of PTCL. First described as a separate TCL subgroup in the 1990 REAL (Revised European-American Lymphoma) classification, 6 they are estimated to represent about 1.4% of all TCL, with about 100 cases reported in the literature. 4
The GDTCL cells tend to live in mucosa, lymphoid tissue, epithelial-rich tissues (skin, gastrointestinal tract), and red pulp of spleen. 7 They develop from thymic precursors in bone marrow and are CD4-/CD8- and thus known as double negative cells.8 They mimic natural killer cells, behave as cytotoxic cells, and are capable of TCR rearrangement as well as phagocytosis. 9
Hepatosplenic GDTCL are usually phenotypically CD2+, CD3+, CD4-, CD5-, CD7+, CD8-, and TCR γ-δ+. 10 They are rarely associated with Epstein-Barr virus infection; reported cases seem more common in Asia. 11 Peak incidence is in young men (median age 20-25 years; male:female ratio 10:1). At-risk populations include the chronically immunosuppressed, including solid organ transplanted patients and patients under prolonged antigenic stimulation. 12
The most common clinical features of HSGDTCL include B symptoms (fever of unknown origin, night sweats, loss of > 10% of body weight), marked HSM, and lack of lymphadenopathy. Patients often present with fever, weakness, and abdominal pain. Laboratory test results
typically show abnormal liver function and abnormal lactate dehydrogenase levels. Bone marrow is almost always involved, with possible trilineage cytopenia. Anemia and thrombocytopenia are reported in 75% and 85% of cases, respectively. 13
Warm (70%) and cold auto-antibodies are the 2 classifications of AIHA. 14 The AIHA can be primary, idiopathic, or a manifestation of underlying disease conditions, including non-Hodgkin lymphomas, systemic autoimmune diseases, chronic infections, postorgan transplantation, and solid tumors. It has also been reported as a complication of treatment with nucleoside analogues. 15
Lacking specific symptoms, HSGDTCL is usually diagnosed late. The diagnosis should be suspected in young men who present with the aforementioned symptoms. However, not everyone with HSGDTCL falls in that group—the present patient was a 77-year-old woman.
Hepatosplenic GDTCL staging is similar to staging of other non-Hodgkin lymphomas. Total-body CT with contrast, bone marrow aspiration/biopsy, and direct lesion biopsy are required. Although positron emission tomography is generally thought to be as useful in TCL as in B-cell lymphomas, there is not enough evidence to support its use specifically in HSGDTCL.16 The staging classification follows the Ann Arbor system, with the majority of cases classified as stage IV.
Hepatosplenic GDTCL are aggressive tumors with a strong tendency to rapidly progress, and they are highly resistant to primary chemotherapy agents. Remission is rarely complete with use of conventional chemotherapy agents. Most patients die of the disease within 2 years of
diagnosis.12 Although the rarity of HSGDTCL has made it difficult to identify any clear prognostic factors, a correlation between thrombocytopenia severity and disease progression has been found in many studies. 17 There is no standard treatment regimen. Proposed therapies
include splenectomy (for diagnosis or thrombocytopenia management), corticosteroids, alkylating agents, purine analogue, anthracycline-containing regimens, and cytarabine/cisplatin combinations. The anthracycline-based regimen most commonly used as first-line therapy is CHOP, or CHOP derivatives, with complete remission rates between 30% and 45%. However, long-term results remain disappointing (median relapse time 4 months).10 In 3 reviews, median survival was 16 months, 11 months, and 9.5 months.10,17,18 In the International T-Cell Lymphoma Project study, the 5-year failure-free survival rate was 0%, and the overall survival rate was 7%.4 In these studies, the majority of patients received some variation of CHOP-based therapy, and although positive responses were appreciated in many of the cases, they were generally short-lived.