NEW YORK (Reuters Health) – Patients with non-castrate metastatic prostate cancer receiving androgen deprivation therapy fare no better with the addition of docetaxel chemotherapy, a French and Belgian team reports.

Furthermore, adverse events are much worse with adjunctive chemotherapy. “Docetaxel should not be used as part of first-line treatment for patients with non-castrate metastatic prostate cancer,” the investigators conclude in their report in Lancet Oncology published online January 8.

Dr. Gwenaelle Gravis, at the Centre de Recherche en Cancerologie de Marseille, France, and colleagues explain that metastatic prostate cancer eventually becomes resistant to anti-androgen treatment, at which point the only treatment shown to improve survival was docetaxel. This suggested early chemotherapy might also improve outcomes in metastatic prostate cancer while it was still hormone-sensitive.

To test this, the team conducted a randomized, open-label trial in which 192 patients with non-castrate metastatic prostate cancer were assigned to androgen deprivation therapy (orchiectomy or LHRH agonists) plus docetaxel, while 193 patients received ADT alone.

Median overall survival in the two groups was 58.9 months and 54.2 months, respectively, which translated to a nonsignificant hazard ratio of 1.01, the authors found.

Also, 72 serious adverse events occurred in the ADT + docetaxel group, while there were none in the ADT-only group, the report indicates.

Biochemical and clinical progression-free survival rates were both significantly longer in the ADT + docetaxel group, but the researchers found that the efficacy of docetaxel waned before progression occurred. They say this may explain the lack of difference in overall survival despite the short-term benefit of chemotherapy on biological variables.

Overall, Dr. Gravis and colleagues conclude: “As has been previously described with other cytotoxic drugs, the addition of docetaxel to androgen-deprivation therapy did not improve survival compared with androgen-deprivation therapy alone in metastatic non-castrate prostate cancer in our study.”

SOURCE: Androgen-deprivation therapy alone or with docetaxel in non-castrate metastatic prostate cancer (GETUG-AFU 15): a randomised, open-label, phase 3 trial
Lancet Oncol 2013.