Epidemiology and Prognostic Factors of Angioimmunoblastic T-Cell Lymphoma

Background:

Peripheral T cell lymphomas (PTCL) constitute only 10-15% of non-Hodgkins lymphoma, and is a heterogenous group of lymphomas. Angioimmunoblastic T-cell (AIB-T) lymphoma is a subset of peripheral T cell lymphomas. It is a highly aggressive malignancy originating from follicular subset of mature CD4+ helper T cell, with a high risk of relapse. AIB-T lymphoma commonly present with generalized lymphadenopathy, hepatosplenomegaly or systemic B symptoms. Diagnosed upon biopsy, AIB-T lymphoma is characterized by polymorphic infiltration of lymph nodes and manifest significant proliferation of follicular dendritic cells and high endothelial venules. Treatment options include chemotherapy (often CHOP with or without etoposide) and autologous hematopoietic stem cell transplant.

Method:

Data was collected from Surveillance, Epidemiology and End Result database Research Plus Data, 17 Registries, Nov 2022 Sub (2000-2020). AIB-T lymphoma cases diagnosed including and after the age of 20 years were extracted from the data base using the ICD Code 9705/3. The data was stratified based on age, sex, race, primary site labelled and chemotherapy, and survival curves were compared using the Log-Rank test (GraphPad Prism).

Results:

Total 2536 cases of angioimmunoblastic T-cell lymphoma were identified, of which ~54.85% were males. The neoplasm was most commonly seen in White (66.68%) patients followed by Hispanic (14.08%), Asians/Pacific Islander (10.92%), Black (7.89%) and Alaskans/Native American (0.28%) patients. The median age of diagnosis was 69 years. The incidence rate (per million population) for the general population is around 0.05 per year. When comparing the survival curves, the data was statistically significant for age, with survival progressively tailing off with increasing age (p value <0.0001). The median of survival (mOS) for males was 17 months and females was 25 months (CI:0.619-0.746, HR: 1.159, p 0.0021). Survival analysis based on race and primary site labelled showed no statistical difference. The mOS calculated for chemotherapy was significant for 28 months (with chemo) vs 4 months (without chemo) (p value <0.0001).

Conclusions:

Angioimmunoblastic T-cell lymphoma is a rarely seen malignancy with only 2536 cases reported in the last two decades in SEER database. It has predilection for males, and majority of the cases were reported in Caucasians. Overall superior survival was observed with younger age groups, female gender and treatment with chemotherapy. Race and primary site of origin showed no association with the median of survival. Given its extremely low incidence, more research and analysis is warranted to understand this lesser known malignancy.

No relevant conflicts of interest to declare.