Greater chemo use confers small survival benefit in elderly patients with metastatic prostate cancer

In the era of combination chemotherapy (CCE), clinical practice for treating elderly patients with metastatic prostate cancer (mPC) appears to be changing despite limited data, a recent study has shown.

“An increasing proportion of older patients are receiving chemotherapy, and an increasing number of chemotherapeutic agents are being administered, despite the limited availability of prospective data in older patients with mPC,” researchers said.

The retrospective analysis included 473 elderly mPC patients who were being treated at a tertiary academic cancer centre between 2000 and 2015. Most patients (n=280) were diagnosed between 2000 and 2009 and were designated as the pre-CCE group, while the remaining 193 were included in the post-CCE arm.

The use of chemotherapy increased significantly, from 69 percent in the pre-CCE group to 82 percent in the post-CCE group (p<0.005). The same was true for the median number of chemotherapeutic agents given, which grew from one to two (p<0.005).

In terms of specific agents, fluoropyrimidine, platinum, taxane and irinotecan all saw significant spikes in use in the post-CCE arm (p<0.005 for all).

Kaplan-Meier analysis showed that these changes in treatment practices correlated with a small but statistically significant increase in survival. Patients in the pre-CCE group survived for a median of 5 months as compared to 6 months in the post-CCE arm (p<0.005). In contrast, the use of combination chemotherapy does not seem to significantly improve survival.

While existing trials have demonstrated the survival benefits of combination chemotherapy regimens for mPC, elderly adults are underrepresented in these studies, the researchers said. The present findings show that treatment practices in the elderly have changed in response to such literature despite thin evidence.

Future studies should focus on the efficacy of alternative dosing and scheduling regimens in elderly patients, they added.