# Clear cell renal cell carcinoma combined with intravascular large B-cell lymphoma: a case report and review of the literature

## TL;DR

This paper reports a rare case of kidney cancer combined with a type of lymphoma, highlighting the challenges in diagnosis and treatment.

## Contribution

The paper presents a rare case of ccRCC combined with IVLBCL, emphasizing the diagnostic difficulties and clinical implications.

## Key findings

- The lymphoma component was confined within the blood vessels of the RCC, leading to potential misdiagnosis.
- The patient showed favorable outcomes after surgery and chemotherapy with 16 months of follow-up.
- The case highlights the need for increased awareness among physicians to improve diagnosis and prognosis.

## Abstract

Clear cell renal cell carcinoma (ccRCC) combined with intravascular large B-cell lymphoma (IVLBCL) is an extremely rare collision tumor, and its coexistence is often missed or misdiagnosed, making clinical diagnosis and treatment notably difficult.

We present the case of a 68-year-old male, in whom imaging revealed a nodular soft tissue density shadow in the parenchyma of the left kidney. Immunohistochemistry and molecular testing confirmed the combination of ccRCC and IVLBCL. Following surgery, the patient underwent comprehensive examinations, including bone marrow biopsy and cytology, to rule out systemic lymphoma involving the kidneys. The patient received postoperative chemotherapy and was still in a favorable condition after 16 months of follow-up.

In the ccRCC combined with IVLBCL, the lymphoma component is confined within the blood vessels of the RCC, making it extremely prone to misdiagnosis, which can lead to a poor prognosis. This case report presents an incidental finding of ccRCC combined with IVLBCL, aiming to raise physician awareness and provide valuable clinical references.