Supplementary Material for: Pulmonary Arterial Hypertension as an Unusual Presentation of Angioimmunoblastic T-Cell Lymphoma (AITL): A Case Report

Introduction: Angioimmunoblastic T-cell lymphoma (AITL) is a rare form of non-Hodgkin lymphoma with diverse clinical presentations. This report describes a unique case of AITL presenting with pulmonary arterial hypertension (PAH), a rarely associated complication. Case Presentation: An 84-year-old male with a history of gastric cancer presented with dyspnea. Initial investigations revealed lymphadenopathy, pleural effusion, and severe PAH. Diagnostic workup, including histopathological and immunohistochemical analysis of an excisional lymph node biopsy and advanced imaging techniques, confirmed the diagnosis of AITL. The patient was treated with a mini-CHOP chemotherapy regimen, leading to significant improvement in PAH and other symptoms, and achieving complete remission as confirmed by positron emission tomography-computed tomography scans. Conclusion: This case highlights the diagnostic challenge posed by atypical manifestations of AITL, such as PAH. The effective response to chemotherapy in this patient emphasizes the potential for conventional treatment regimens in managing rare presentations of AITL. This report contributes to the limited literature on AITL with PAH and underscores the importance of considering AITL in differential diagnoses for patients presenting with PAH.