Phase II study of capecitabine single-agent therapy in patients with metastatic renal cell carcinoma

Systemic therapy for non-clear cell renal cell carcinomas: a systematic review and meta-analysis

CONTEXT

Clinical data supporting the use of targeted agents for the treatment of metastatic renal cell carcinoma (RCC) are based predominantly on patients with clear cell histology. Little is known about the efficacy of these drugs in non-clear cell variants.

OBJECTIVE

To evaluate the efficacy of different clear cell RCC (ccRCC)-approved targeted agents among patients with non-ccRCC compared with ccRCC.

EVIDENCE ACQUISITION

We conducted a systematic review of electronic databases to identify publications evaluating the outcomes of patients with non-ccRCC treated with targeted agents approved for treatment of ccRCC. Patients with sarcomatoid variant RCC were excluded from the main analysis but were evaluated as an independent cohort. End points of interest were response rate, median progression-free survival (PFS), and median overall survival (OS). Where possible, data were pooled in a meta-analysis. For studies of unselected patients with RCC, the outcomes of patients with non-ccRCC histology were compared with ccRCC. In exploratory analyses, outcomes of non-ccRCC with nonapproved agents were assessed.

EVIDENCE SYNTHESIS

A total of 49 studies comprising 7771 patients were included in the analysis. Of these, 1244 patients (16.0%) had non-ccRCC, 6300 (83.1%) had ccRCC, and 227 (2.9%) had sarcomatoid tumours. The overall response rate for non-ccRCC with targeted agents was 10.5%. In studies directly comparing non-ccRCC and ccRCC, there were significantly lower response rates for non-ccRCC (odds ratio for response: 0.52; 95% confidence interval, 0.40-0.68; p<0.001). For non-ccRCC treated with targeted agents, median PFS and OS were 7.4 and 13.4 mo, respectively; for patients with ccRCC, these were 10.5 mo and 15.7 mo, respectively (p value for difference<0.001 for both parameters).

CONCLUSIONS

Patients with non-clear cell renal cell carcinoma (non-ccRCC) have significantly lower response rates and poorer median progression-free survival and overall survival than those with ccRCC. The optimal treatment of patients with non-ccRCC remains unclear and warrants further study.

PATIENT SUMMARY

Systemic treatments for patients with renal cell carcinoma (RCC) tend to be significantly less effective for non-clear cell RCC, with lower response rates and worse progression-free survival and overall survival when compared with clear cell RCC. Optimal therapy remains unclear and warrants further study.

Efficacy of the oral fluorouracil pro-drug capecitabine in cancer treatment: a review

Capecitabine (Xeloda) was developed as a pro-drug of fluorouracil (FU), with the aim of improving tolerability and intratumor drug concentrations through its tumorspecific conversion to the active drug. The purpose of this paper is to review the available information on capecitabine, focusing on its clinical effectiveness against various carcinomas. Identification of all eligible English trails was made by searching the PubMed and Cochrane databases from 1980 to 2007. Search terms included capecitabine, Xeloda and cancer treatment. Nowadays, FDA has approved the use of capecitabine as a first line therapy in patients with metastatic colorectal cancer when single-agent fluoropyrimidine is preferred. The drug is also approved for use as a single agent in metastatic breast cancer patients who are resistant to both anthracycline and paclitaxel-based regimens or when further anthracycline treatment is contraindicated. It is also approved in combination with docetaxel after failure of prior anthracycline-based chemotherapy. In patients with prostate, pancreatic, renal cell and ovarian carcinomas, capecitabine as a single-agent or in combination with other drugs has also shown benefits. Improved tolerability and comparable efficacy, compared with the intravenous FU/LV combination, in addition to its oral administration, make capecitabine an attractive option for the treatment of several types of carcinomas.