Top Line: Do older patients tolerate BID dose escalation for SCLC as well as younger patients?
The Study: Back in 2021, the randomized, phase 2 THORA trial reported an increase in overall survival with 60 Gy in 40 BID fractions compared to 45 Gy in 30 BID fractions for limited stage SCLC. The survival improvement was rather impressive at 74.1% v 48.1% at 2 years and median OS 37 v 23 months. Some might say this was a little too impressive given that there were no significant differences in local failure, distant failure, or disease progression. There was also no difference in toxicity. These debates aside, a secondary analysis of the THORA trial sought to determine if older patients tolerated dose escalation as well as younger patients. Overall, 31% of patients enrolled in THORA were ≥70 years old, however they were a relatively healthy group with no significant difference in baseline comorbidity compared to younger patients. Older patients were just as likely to complete treatment (85% v 92%). They also had similar rates of grade 3+ pneumonitis (2% v 2%) and esophagitis (18% v 21%). Though PFS was similar between older and younger patients, older patients had a lower median OS (24 v 37.2 mo). In the older subset of patients, the survival improvement with dose escalation from 45 to 60 Gy was no longer significant (35 v 44 mo).
TBL: In the THORA trial, patients older than 70 tolerated dose escalation from 45 Gy to 60 Gy just as well as younger patients although they had lower median survival even with dose escalation.
- Killingberg, J Thorac Oncol 2023