Docetaxel Does Not Worsen Long-Term QOL in Metastatic Prostate Cancer

The addition of docetaxel to androgen deprivation therapy (ADT+D) offered decreased quality of life (QOL) at 3 months compared with ADT alone in metastatic hormone-sensitive prostate cancer, but better QOL after 12 months, according to an analysis of the phase III CHAARTED study presented at the 2016 American Society of Clinical Oncology (ASCO) Annual Meeting, held June 3–7 in Chicago (abstract 5004).

“Historically, ADT was the sole treatment for metastatic prostate cancer,” said Linda J. Patrick-Miller, PhD, of the University of Chicago Medical Center, who presented the results. Docetaxel was the first agent to confer an overall survival benefit, in 2004, but “docetaxel has a known side effect profile that might offset its clinical benefit.”

The CHAARTED trial showed that adding the chemotherapy drug to ADT improves overall survival in this malignancy. This analysis compared the groups based on several QOL instruments, including the Functional Assessment of Cancer Therapy-Prostate (FACT-P), the FACT-Taxane, the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue, and the Brief Pain Inventory (BPI); these were collected at 3, 6, 9, and 12 months following randomization.

A total of 790 metastatic prostate cancer patients were included (397 in the ADT+D group, 393 in the ADT alone group); most patients were white, and most patients had an Eastern Cooperative Oncology Group (ECOG) performance status of 0.

The ADT+D patients reported a significant decline from baseline to 3 months on the FACT-P (P < .001), but at 12 months this measure did not differ significantly from baseline (P = .38).

At 3 months, the ADT+D regimen was significantly worse in terms of FACT-P scores than ADT alone (P = .02). By 6 months there was no difference between the groups, and at 12 months this flipped, with significantly better scores with the combination therapy (P = .04). ADT+D patients had significantly poorer scores on the FACIT-F at 3 months (P< .01) as well. Again, that difference disappeared by 6 months, and though it was not significant the ADT+D patients had higher scores at 12 months.

Both the groups reported significantly worse FACT-Taxane scores at all time points compared with baseline, and the ADT+D patients had significantly worse scores at both 3 months and 12 months; Patrick-Miller said this was an expected outcome. Both groups also had worse BPI scores at 9 and 12 months. The BPI scores did not differ between the groups. A measure of emotional well-being was superior in the docetaxel arm at all time points measured.

“Although patients treated with ADT+D report a temporary decrement in overall QOL while on treatment, they return to baseline levels at 12 months, which is significantly better than patients treated with ADT alone,” Patrick-Miller said. The treatment combination, she concluded, “does not confer a long-term negative impact on overall QOL or emotional well-being, and does improve survival.”

The discussant for the session, Derek Raghavan, MD, PhD, of the Levine Cancer Institute in Charlotte, North Carolina, said it is an important finding that “patients are not continually impaired by the after effects of chemotherapy, but they do have a very important survival benefit. Docetaxel-castration is the new standard initial therapy for high-volume metastatic disease.”