Concurrent chemoradiotherapy for large-volume locally-advanced non-small cell lung cancer

Patients with large volume stage III non-small cell lung cancer (NSCLC) are often excluded from concurrent chemoradiotherapy (CRT) protocols due to fears about excessive toxicity and poor survival. Patients with N3 nodal disease may be excluded for the same reason. We have routinely accepted fit patients in both the above groups for CRT if they met our planning parameters. We analyzed toxicity and survival outcomes for patients undergoing CRT with a planning target volume (PTV) exceeding 700 cc, either with or without N3 nodal disease, or a PTV less then 700 cc with N3 disease.

Single center, retrospective study of patients with stage III NSCLC treated with CRT between 2004 and 2011.

121 patients were eligible, with 81% (98/121) having a PTV>700 cc (of whom 33% (32/98) had N3 nodal disease) and 19% (23/121) having N3 disease and a PTV≤700 cc. Grade ≥3 esophagitis and pneumonitis were recorded in respectively 34% and 4% of all patients. Median follow-up for all patients was 37.6 months (mo). Median overall (OS) and progression-free (PFS) survivals were 15.7 mo and 11.6 mo, respectively, OS for all patients with PTV>700 cc was 14.5 mo (19.5 mo with N3 and 13.2 mo without N3), compared to 26.5 mo for PTV≤700 cc with N3 (p=0.009). About 1 in 4 patients with PTV>700 cc died within 6 mo of starting radiotherapy (this was associated with Charlson comorbidity index [CCI]≥1), while about 18% were alive at 3 years.

Patients undergoing CRT for stage III NSCLC with a PTV>700 cc, with or without N3 nodal disease, had a significantly shorter OS than patients with PTV≤700 cc with N3. Patients with PTV>700 cc and with CCI≥1, had a significantly higher risk of early death but longer-term survivors with PTV>700 cc are observed. The PTV and CCI should be considered in clinical decision making and used as stratification factors in future trials.