Spontaneous Rupture of a Small Chromophobe Renal Cell Carcinoma Presenting as Wunderlich Syndrome

Chromophobe renal cell carcinoma rarely causes spontaneous renal hemorrhage and enhances weakly on computed tomography. We report a case in which the tumor was masked by a perirenal hematoma for 11 months.

A 46-year-old woman presented with spontaneous renal hemorrhage and no visible renal mass. Magnetic resonance imaging (MRI) at 6 months showed an enhancing lesion indistinguishable from organizing hematoma; because it was shrinking with the hematoma, observation was continued. At 11 months, the hematoma had resolved and a 25-mm solid mass remained. Partial nephrectomy revealed pT1a chromophobe renal cell carcinoma without necrosis or sarcomatoid differentiation. She remained recurrence-free at 5 years.

This case demonstrates spontaneous rupture of a small tumor without aggressive pathological features. When the cause of spontaneous renal hemorrhage remains unclear, serial imaging should be considered until hematoma resolution to avoid missing an occult malignancy.