# Concurrent Chylothorax, Chylopericardium, and Superior Vena Cava Syndrome in a Young Male With Primary Mediastinal Large B-cell Lymphoma: A Report of a Rare Case

## TL;DR

A rare case of a young man with aggressive lymphoma presented with unusual complications requiring advanced diagnosis and treatment.

## Contribution

This report describes a rare combination of chylothorax, chylopericardium, and SVC syndrome in a PMBCL patient.

## Key findings

- A 23-year-old male presented with a rare triad of complications associated with primary mediastinal large B-cell lymphoma.
- The patient showed early improvement with DA-EPOCH-R chemotherapy after a complex diagnostic process.
- The case emphasizes the need for prompt diagnosis and treatment in atypical PMBCL presentations.

## Abstract

Primary mediastinal large B-cell lymphoma (PMBCL) is an uncommon and aggressive subtype of non-Hodgkin lymphoma (NHL) that predominantly affects young adults and typically presents with a bulky anterior mediastinal mass. We report the case of a 23-year-old male who presented with progressive dyspnea, orthopnea, and facial swelling, subsequently found to have superior vena cava (SVC) syndrome, chylothorax, and chylopericardium, an exceedingly rare triad of complications. Diagnostic evaluation required integration of advanced imaging, fluid analysis, and histopathological confirmation, ultimately establishing a diagnosis of stage III PMBCL with low-level bone marrow involvement. The patient was initiated on dose-adjusted rituximab, etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin (DA-EPOCH-R) chemotherapy, with early symptomatic improvement during the first cycle. This case highlights the diagnostic challenges and management complexities of atypical PMBCL presentations and underscores the importance of early recognition and prompt initiation of systemic therapy in patients presenting with recurrent chylous effusions and mediastinal pathology.