Metastatic renal oncocytic neoplasm with benign histologic appearance

Area of Science:

• Nephrology
• Oncology
• Pathology

Background:

• Renal oncocytomas are typically benign kidney tumors.
• Distinguishing benign from malignant renal oncocytomas is crucial for patient management.

Observation:

• A case of malignant renal oncocytoma presented with benign histologic features.
• Metastases to the spine and liver also showed benign histologic characteristics.

Findings:

• Histologic appearance can be misleading in differentiating benign from malignant renal oncocytomas.
• Accepted diagnostic criteria may not suffice in all cases.

Implications:

• This case underscores the potential difficulty in diagnosing malignant renal oncocytoma.
• Clinical course may not correlate with initial benign histologic findings, necessitating careful monitoring.