The phase III CONVERT trial compared twice-daily vs once-daily concurrent chemoradiotherapy in elderly patients with limited-stage small-cell lung cancer.
Concurrent chemoradiotherapy can be administered safely among fit elderly patients with limited-stage small-cell lung cancer (LS-SCLC), according to an analysis from the CONVERT trial.
“The optimal treatment for elderly patients with LS-SCLC is not established,” wrote study authors led by Corinne Faivre-Finn, MD, PhD, of the Christie NHS Foundation Trust in Manchester, United Kingdom. “There is a lack of high-level evidence to guide treatment in older patients as a result of their under-representation in clinical trials.”
The phase III CONVERT trial compared twice-daily vs once-daily concurrent chemoradiotherapy in 490 patients who were 18 years or older; the new analysis compared those aged 70 years and older (67 patients; 14%) with those younger than 70. The inclusion criteria, such as a performance status of 0 or 1 (or 2 due to disease-related symptoms and not comorbidities), meant that only “fit” elderly patients were included. Patients received either 45 Gy in 30 twice-daily fractions over 19 days or 66 Gy in 33 once-daily fractions over 45 days, both concurrent with platinum-based chemotherapy. The results were published in the Journal of Thoracic Oncology.
Among the older group, the median age was 73 years, compared with a median of 60 years in the younger group. Most patients in both groups received 4 chemotherapy cycles, and there was no difference between older and younger patients in number of cycles received. Compliance with radiotherapy was worse in the elderly cohort, with 73% receiving the optimal number of fractions compared with 85% in the younger group (P = .03).
After a median follow-up of 46 months, the 2-year survival rate was 53% in the elderly group of patients and 57% in the younger group; median survival was 29 months and 30 months, respectively, for a hazard ratio (HR) of 1.15 (95% CI, 0.84–1.59; P = .38). The median time to local or distal disease progression was 18 months in the older group and 16 months in the younger group, for an HR for progression-free survival of 1.04 (95% CI, 0.76–1.41; P = .81).
There were some differences with regard to toxicity between the groups. Older patients were more likely to experience neutropenia (84% vs 70%; P = .02) and thrombocytopenia (28% vs 18%; P = .05). However, rates of neutropenic sepsis, hospitalization, and transfusion of red blood cells or of platelets were similar. Grade 3/4 radiation esophagitis and pneumonitis were also similar between elderly and younger patients.
“Our results are particularly relevant as robust evidence to guide treatment decisions in elderly LS-SCLC patients is lacking,” the authors wrote, adding that the study shows this therapy should be an option for fit elderly patients. “Certainly up to the age of 80 years chronological age as a sole factor should not be a barrier to this treatment being offered.”
In an accompanying editorial, Judith van Loon, MD, PhD, and Anne-Marie C. Dingemans, MD, PhD, of the Maastricht University Medical Center in the Netherlands, agreed that the treatment seems like a good option for fit patients, though they pointed out that the study was not designed to assess age differences and is limited by potential selection bias. They also noted that while 70 years is often used as a cutoff for definitions of elderly patients with cancer, with LS-SCLC that would divide the patient population approximately in half, making its utility questionable.
“Future study should focus on incorporating a form of geriatric assessment to support treatment selection,” the authors wrote. “Furthermore, to obtain evidence that can be extrapolated to daily clinical practice, in all studies aiming to collect evidence on the optimal treatment for elderly patients, extra effort should be put into collecting data from patients not fulfilling the study criteria or not willing to participate.”