Purpose: Collecting duct carcinoma (CDC) of the kidney is an aggressive disease with a poor prognosis, accountings for less than 1% of all renal cancers. To date, no standard therapy for CDC has been established. The aim of this study is an investigation of clinicopathologic findings of CDC and correlation of the disease status with a prognosis.
Materials and methods: From 1996 to 2009, 35 patients with CDC were treated at eight medical centers. The diagnosis of CDC was made based on nephrectomy in 27 cases and renal biopsy in eight cases.
Results: Median PFS and OS for all patients were 5.8 months (95% CI 3.5 to 9.2) and 54.4 months (95% CI 0 to 109.2), respectively. The OS of patients with Stages I-III was 69.9 months (95% CI 54.0 to 85.8), while that of patients with Stage IV was 8.6 months (95% CI 0 to 23.3), which showed a statistically significant difference (p=0.01). In addition, among patients with Stage IV, the OS of patients who received a palliative treatment (immunotherapy, chemotherapy, or targeted therapy) was 18.4 months, which was higher than the OS of patients without treatment of 4.5 months.
Conclusion: CDC is a highly aggressive form of renal cell carcinoma. Despite most of the treatments, PFS and OS were short, however, there were some long-term survivors, therefore, conduct of additional research on the predictive markers of the several clinical, pathological differences and their treatments will be necessary.
Keywords: Kidney; Prognosis; Renal cell carcinoma; Treatment.