# Anaplastic large cell lymphoma in the penis: a case report and review of literature

## TL;DR

A rare case of anaplastic large cell lymphoma in the penis is reported, highlighting the challenges in diagnosis and treatment.

## Contribution

This case report presents a rare instance of primary T cell lymphoma in the penis and its successful treatment with an atypical regimen.

## Key findings

- A 60-year-old male was diagnosed with anaplastic lymphoma kinase-negative primary cutaneous anaplastic large cell lymphoma of the penis.
- The patient achieved a complete metabolic response after treatment with brentuximab vedotin plus CHOP chemotherapy.
- The case emphasizes the need for individualized treatment strategies for rare, localized, and multifocal lymphomas.

## Abstract

Anaplastic large cell lymphoma is a distinct subtype of mature T cell lymphoma characterized by strong CD30 expression. While primary penile lymphomas are rare, they are most commonly of B cell origin, making primary T cell lymphomas of the penis an exceptional finding that can pose significant diagnostic challenges.

A 60-year-old Arab male presented with multiple, rapidly growing nodules on the penile body that had developed over 4 weeks. A comprehensive workup, including biopsy and immunohistochemistry, confirmed a diagnosis of localized, anaplastic lymphoma kinase-negative primary cutaneous anaplastic large cell lymphoma. Staging via positron emission tomography–computed tomography revealed no systemic involvement. The patient was treated with six cycles of brentuximab vedotin plus cyclophosphamide, doxorubicin, vincristine, and prednisone, achieving a complete metabolic response (Deauville score of 2) as assessed by post-treatment positron emission tomography–computed tomography imaging.

This case highlights the diagnostic challenge posed by rare penile lesions and, more importantly, the therapeutic dilemma of selecting an appropriate treatment for a disease that is localized yet multifocal. The successful outcome with systemic brentuximab vedotin plus cyclophosphamide, doxorubicin, vincristine, and prednisone therapy, a deviation from standard guidelines for unifocal primary cutaneous anaplastic large cell lymphoma, underscores the need for individualized treatment strategies and further research to establish risk-adapted guidelines for this rare clinical entity.