New Treatment Options in Breast Cancer – Dr David Miles on Xeloda (Capecitabine) and Taxotere (Docetaxel).

Perth Doctors have been fortunate enough to receive the latest treatment options in breast cancer presented by Dr David Miles from Guy’s Hospital in London. Dr David Miles heads the cancer research UK Breast Cancer Biology Group at Guy’s hospital and is published extensively on biological therapies for breast cancer. He discussed new treatment options in breast cancer, in particular Xeloda (Capecitabine) and Taxotere (Docetaxel) in combination.

The current usual practice is for 1st chemotherapy for breast cancer to be adriamycin plus cyclophosphamide (AC). If that fails, 2nd line treatment is usually with a taxane e.g. Paclitaxel or Docetaxel.

Dr Miles reviewed the treatment, please see below.

The addition of Capecitabine to Docetaxel, which he felt was a new standard of care after AC failure, produces superior overall survival (OS) to Docetaxel alone.

Another very effective agent in breast cancer is 5FU. Normal 5FU is very unpredictable in its absorption in the gut and Dr Miles explained that Capecitabine was the result of reverse engineering to produce a chemical 5FU which was absorbed better in the gut. Capecitabine is metabolised to the active anti-cancer chemical by the enzyme thymidine phosphorylase.

Dr Miles reviewed the results of a phase III trial of Docetaxel verses Docetaxel plus Capecitabine. All patients were pre-treated with anthracyclines and 75% had 5FU, 10% had paclitaxel. Approximately half the patients were being treated second line. Response rate (RR) to the combination was 42% and single agent Docetaxel RR was 30%.

Side effects included stomatitis, diarrhoea and hand foot syndrome were more common in combo, but, fever, neutropenia and myalgia were much less common. Also, the number of patients with severe symptoms was actually quite low.

Did the choice of post study chemotherapy influence survival?

Those treated with single agent Capecitabine after disease progress had median survival of 22 months, whereas about 11 months for all other combined. Vinorelbine had a median survival of 13.6 months whereas 12.2 months compared to all other therapy.

Dr Miles made the point that in the context of metastatic disease the newer therapies addressed the issues of quality of life as well as actually prolonging survival.