# A Case of Rosai–Dorfman Disease Complicated by Bone Metastasis From Prostate Cancer

## TL;DR

This paper presents a rare case where a patient had Rosai-Dorfman disease alongside prostate cancer bone metastasis, highlighting the need for accurate diagnosis.

## Contribution

The novelty lies in documenting a rare co-occurrence of RDD and prostate cancer metastasis, emphasizing the importance of histopathological confirmation.

## Key findings

- RDD was confirmed in retroperitoneal lymphadenopathy initially suspected as prostate cancer metastasis.
- The case highlights the diagnostic challenges of distinguishing RDD from cancer metastasis.
- Histopathological verification is crucial for accurate diagnosis and treatment planning in atypical cases.

## Abstract

Rosai-Dorfman disease (RDD) is a rare myeloproliferative disorder of histiocytes. The cause of the disease remains unclear. RDD mainly affects lymph nodes and has many extranodal manifestations, including the skin, lungs, eyes, and gastrointestinal tract. This report details a diagnostically challenging case where retroperitoneal lymphadenopathy initially suspected as metastatic prostate adenocarcinoma was pathologically confirmed as RDD. The concurrent occurrence of these two distinct pathologies underscores the importance of histopathological verification in atypical presentations, particularly for guiding precision oncology management.