Abstract
BACKGROUND: Chromophobe renal cell carcinoma is a rare histological subtype, accounting for only 5-6% of renal cell carcinoma cases. It exhibits low aggressiveness and has an overall favorable prognosis with a very low risk of developing metastatic disease. Genetic syndromes such as Birt-Hogg-Dubbé may be associated with this renal cell carcinoma subtype. Owing to limited clinical data, therapeutic regimens for advanced chromophobe renal cell carcinoma are often extrapolated from treatment protocols for clear cell renal cell carcinoma or studies combining several non-clear cell renal cell carcinoma types. CASE PRESENTATION: We report a case of a 54-year-old Austrian male patient presenting with metastatic liver disease from chromophobe renal cell carcinoma, confirmed by biopsy, 18 years after the initial diagnosis of a non-metastasized, grade 2, pNO, pT2 tumor with R0 resection. The patient underwent regular follow-up examinations and had no clinical symptoms at the time of recurrent disease diagnosis. Family history for genetic syndromes was negative. The multidisciplinary tumor board decided to treat the patient with a novel first-line palliative therapy using combined immuno-/tyrosine kinase therapy with pembrolizumab/lenvatinib. A multiphasic computed tomography scan performed 3 months after initiation of therapy showed a complete response. CONCLUSION: Although chromophobe renal cell carcinoma typically has excellent progression-free survival and overall survival rates in localized disease, those patients with larger tumors or those with sarcomatous features, as well as PT53 mutations, seem to have worse outcomes due to metastatic development. This case report affirms that patients with chromophobe renal cell carcinoma exhibiting these risk factors should undergo closer and long-term follow-up after curative surgery.