Transitional cell carcinomaterm (TCC) of the urothelium (these are epithelial cells that mainly line the urinary tract) is usually treated with a combination regimen of methotrexate/vinblastine/doxorubicine/cisplatin (known as M-VAC). Recent reports from a phase III trial showed that M-VAC versus gemcitabine plus cisplatin (GC) had similar response rates, time to progression and overall survival. However, GC was less toxic than M-VAC and the need for overall survival improvement needed to be increased. This article presents a phase II study of a combination of gemcitabine and docetaxel. Gemcitabine [Gemzar from Eli Lilly] is a DNA analogue that inhibits DNA synthesis ultimately leading to cell death. Docetaxel [Taxotere from Sanofi Aventis] is a paclitaxel analogue that stabilizes tubulin ultimately preventing cellular division and leading to cell death. These two drugs are thought to have a synergistic effect. That is, the combination effect of the two drugs is greater than that predicted from the effects from single drug therapy.

    The trial included 34 patients with advanced TCC that was unresectable for cure or had measurable metastasistermterm were non-randomly selected with primary tumor sites being 26 bladder, 5 kidney, and 3 ureter. 7 patients had previous chemotherapyterm (21%). 82% had previous surgery to remove the primary tumor, with 20 patients having some form of metastasis. Haematologic (blood) toxicity was common during treatment (24% in some side effectsterm). A complete response (CR) was seen in 2 patients (5.8%) where all lesions or growths disappeared. A partial response (PR) was seen in 16 patients where the lesion or growth size was decreased by 30% or more. This gave an overall response rate (OR) of 53%. One aspect the study noted was a shift in the distribution of gemcitabine from the plasmid to the red blood cells (RBC).
One part the researchers note in the study is the high OR rate. Other studies of this combination of drug have shown OR rates of 17% as a second line and 33% as a first line of treatment. The researchers suggests the reason for the better response rate in their study is their study has a larger number of patients who have never been treated with chemo drugs (chemotherapy-naïve) and has a more favorable drug administration schedule.