Hepatosplenic T-Cell Lymphoma: A SEER Stat Review of Epidemiology

Background:

Hepatosplenic T-cell Lymphoma (HSTCL), historically known as hepatosplenic gamma/delta T cell lymphoma, is an extremely rare and highly aggressive subtype of peripheral T-cell lymphomas. Characterized by malignant proliferation of cytotoxic T cells, usually expressing gamma/delta T cell receptors but infrequently alpha/beta receptors as well, HSTCL presents with hepatosplenomegaly, thrombocytopenia, or systemic B symptoms. The aim of this study is to investigate epidemiology and survival outcomes based on independent prognostic factors in adult patients with HSTCL over the last two decades.

Method:

The data was collected from Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2023 Sub (2000-2021). We extracted cases of Hepatosplenic T-cell lymphoma in adults of age 20 years and above, using the ICD code 9716/3. The data was stratified on the basis of age, gender, race, primary site labelled, stage, treatment types, and median household income inflation adjusted to 2022. The analysis was further completed by comparing survival using the Log-rank test (GraphPad Prism).

Results:

From 2000 to 2021, 163 cases of HSTCL were identified in adults of age 20 years and above. 63.8% of the reported cases were males and 36.2% were females. Race-specific distribution observed in descending order was: Caucasian (57.69%), Black (20.86%), Asian/Pacific Islander (11.66%), Hispanic (9.20%) and Native American/Alaskan (0.61%). The median age of diagnosis was 48 years. Further comparison of the survival curves based on age, gender, race, primary site labelled, stage, and inflation adjusted-median household income showed no statistical significance. Survival analysis calculated for chemotherapy and radiation therapy (XRT), as the primary treatment modality, also didn't show any significant association. The sole prognostic factor in our study that showed statistically significant association with survival outcomes was surgical management. The MoS compared for surgery was 22 months and no-surgery was 7 months (CI: 2.138 - 4.621, HR 0.6412, p value 0.0207).

Conclusion:

Hepatosplenic T-cell lymphoma is an ultra-rare malignancy, accounting for <1% of all non-Hodgkins lymphomas. This aggressive tumor has poor outcomes, even with standard-of-care treatment approaches. HSTCL is most commonly observed in male gender and Caucasian race. Our study showed no influence on survival outcomes based on age, race, gender, primary site labelled, stage and income. While improved survival was observed in patients treated surgically, chemotherapy/XRT had no impact on MoS. More studies are needed to better understand and aid in management of this rare but hostile neoplasm.

No relevant conflicts of interest to declare.