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Anti-VEGF drugs combined with gemcitabine-based chemotherapy in treatment of metastatic collecting duct carcinoma.

403^ Background: Collecting duct carcinoma (CDC), accounting for less than 1% of kidney cancer, demonstrates an aggressive course and extremely poor prognosis. There are still no standard treatment regimens for this disease at present. Sunitinib and sorafenib, two protein tyrosine kinase inhibitors, have been used in treatment of renal cell carcinoma mainly by inhibiting vascular endothelial growth factor receptor (VEGFR). However, the combination of anti-VEGF drugs with gemcitabine-based chemotherapy has not been tested in CDC treatment.


METHODS
From Jun 2008 to Aug 2010, six patients (5 males and 1 female) with metastatic CDC, ECOG PS ≤ 2 and adequate organ function were enrolled in the trial. Four patients received sorafenib (400mg bid) and two received sunitinib (37.5mg Qd), all in combining with gemcitabine (1.0 g/m2 d1,8) and cisplatin (40 mg d1-3) Q28d. A mean of 2.3 cycles (range 1-4 cycles) was given. Performance status 0-2 was allowed. Tumor assessments and radiological evaluations were conducted every 4 weeks.


RESULTS
The median age was 41.5 years (range 28-60 years). All patients received prior nephrectomy. The sites of metastases included lung (4/6), skeleton (3/6), mediastinal lymph node (2/6), and liver (1/6). The therapy was well tolerated with grade 3-4 toxicities: neutropenia (4/6), thrombocytopenia (2/6), hand-foot syndrome (1/6) and rash (1/6). One patient had partial response, four had stable disease, and the disease control rate was 83.3% (5/6). The median progression-free survival was 3.5 months (range 1-6+ months), and the median overall survival was 6.5 months (1-15+ months) with the median follow-up of 6.5 months. No drug related deaths occurred.


CONCLUSIONS
The combination of anti VEGF drugs and gemcitabine based chemotherapy are well tolerated. This treatment regimen demonstrates modest antitumor activity and may cause progression-free survial benefit in patients with CDC. [Table: see text].