Collecting duct carcinoma of the kidney: a clinicopathological study of five cases.

OBJECTIVE: To investigate the clinicopathological features of collecting duct carcinoma (CDC) and improve its diagnosis and treatment.

METHODS: A retrospective analysis was performed with clinical data including follow-up results of five patients with CDC.

RESULTS: A total of 5 cases, including 4 males and 1 female, were included in this analysis with the average age 54 years (range 42 to 65). Patients mainly suffered from lumbar pain, hematuria, abdominal mass and low grade fever. Four patients underwent radical nephrectomy while another received palliative nephrectomy. Lymph node metastasis occurred in 3 cases and renal hilum fat metastasis happened to 2 other cases. Tumors was located in the renal medulla and presented invasive growth. They had a tubulopapillary architecture with the hobnail-shaped cells protruding into the glandular lumen, and were accompanied by interstitial fibrosis and dysplasia of epithelial cells in collecting ducts adjacent to the tumors. One tumor was staged at AJCC II, two at AJCC III and two at AJCC IV. Postoperative interferon immunotherapy was applied in 2 cases. Patients were followed up for 5 to 18 months and the average survival time was 10 months.

CONCLUSION: The CDC exhibits special clinicopathological features, high degree of malignancy and poor prognosis. The diagnosis depends on the histopathological examination. Early detection and early surgical treatment are still the main methods to improve the prognosis of patients with CDC.