Efficacy of carboplatin and paclitaxel therapy in patients with advanced squamous cell carcinoma (SCC) of the anal canal.

Abstract

539 Background: Development of distant metastases in SCC of the anal canal is not very common after treatment with combined modality. Only widely published data for treatment of metastatic disease is cisplatin and 5-FU. Carboplatin and paclitaxel is commonly used in squamous cancer of the lung but its efficacy in SCC of the anal cancer is unclear. The objective of this study is to determine the tolerability and outcome of patients with SCC of the anal canal treated with carboplatin/paclitaxel at Moffitt Cancer Center. Methods: Retrospective analysis was conducted looking at Moffitt Cancer tumor registry from 1/2007 to 1/2012. Eligible patients were required to have diagnosis of SCC of the anal cancer and received carboplatin/paclitaxel every 3 weeks as part of the treatment. Results: 13 patients fulfilled the criteria. 11 patients were initially diagnosed with early stage (Stage I-III). 11 patients received concurrent chemo radiation (Nigro regimen or cisplatin + 5-FU) and had reoccurrence. 2 patients were initially diagnosed with Stage IV disease. Median age was 56 years and 77% were females. Upon diagnosis of metastatic disease, 11 patients received prior chemotherapy (cisplatin/5FU, irinotecan/cetuximab, cisplatin/docetaxel). 4/13 patients received 2 prior chemotherapy regimens, 7/13 received only 1 prior regimen and 2/13 did not receive any prior chemotherapy. Patients received an average of 4.7 cycles (1 cycle= 3 weeks). Median was 4 cycles. The response rate was high at 62% with 2 patients achieving complete response and 6 patients with partial response. Grade 3 toxicities included peripheral neuropathy (n= 3), diarrhea (n= 1), and infection (n=3). 4 patients had grade 3 neutropenia and 1 patient had grade 4 anemia. Median progression free survival and overall survival were 4.6 and 10.5 months respectively. Conclusions: Carboplatin and paclitaxel seem to be well tolerated and have activity in the treatment of advanced SCC of the anal canal. Larger studies need to be conducted to validate these findings.