Elderly patients with early-stage lung cancer benefit from adjuvant chemotherapy after surgery without showing increased toxicity compared with younger patients, according to a presentation at the annual meeting of the American Society of Clinical Oncology.

Several recent large-scale trials have shown significant benefits to giving platinum-based chemotherapy combinations to early-stage lung cancer patients following surgery to eliminate residual disease. However, it was not known whether patients older than 65 years would derive the same benefits as younger patients.

“Generally speaking, we approach elderly patients with extra caution because many of them have other medical problems that can complicate treatment,” said Carmela Pepe, MD, a clinical research fellow at Princess Margaret Hospital in Toronto, and the study’s lead author. “With these findings, we hope that physicians and patients can be assured that elderly patients will have a prolonged life and can be given this treatment without a fear of increased side effects because of their age.”

JBR.10 was a large North American Intergroup trial led by the National Cancer Institute of Canada Clinical Trials Group that compared cisplatin and vinorelbine chemotherapy with observation for patients with early-stage non-small cell lung cancer. In the current analysis, researchers retrospectively compared outcomes for 327 young and 155 elderly (over age 65 years) patients who were matched for baseline prognostic factors.

In JBR.10, they found that overall survival was significantly better with chemotherapy than observation for both age groups; 69 percent of patients in the treatment group were alive at five years compared with 54 percent in the observation group.

When looking specifically at the elderly population, overall five-year survival was 66 percent in the treatment group compared with 46 percent in the observation group. Although there were no significant differences in rates of toxicity between age groups, elderly patients received significantly fewer doses and were less likely to complete treatment.

In addition, there were no significant differences between younger and older patients in treatment-related hospitalizations (28 percent in the elderly versus 29 percent among younger patients), in toxicities, or in the use of G-CSF, a drug used to help boost production of immune cells (19 percent in the elderly versus 13 percent among younger patients).

The reasons for the lower number of doses among elderly patients are not clear, but may be because both patients and doctors were unwilling to tolerate even mild side effects of treatment, given that the benefits of adjuvant chemotherapy were unproven.

Elderly patients were further subdivided into age groups of 66 to 70, 71 to 75, and older than 75 years to identify more subtle differences in outcomes. Although the benefits of adjuvant chemotherapy for patients up to age 75 years were clear, researchers noted that patients older than 75 years warrant further study because the sample size was so small.