Radiation pneumonitis (RP) in lung cancer patients treated with chemotherapy (CT) and thoracic radiation (TR): Retrospective analyses of patients treated at a comprehensive cancer center: P2-220

Background:

Combined CT and TR is the current standard for locally advanced non-small cell lung cancer (NSCLC) and SCLC. Severe RP, an important adverse effect of TR, is reported in clinical trials to occur in 10% of patients receiving CT and TR. The rate in routine care may be higher as patients are not selected based on lung function. We conducted a retrospective study to assess the incidence of RP in lung cancer patients treated with CT and TR.

Methods:

Retrospectively we identified patients who underwent combined modality therapy (concurrent or sequential CT and TR) for lung cancer (NSCLC & SCLC) at our cancer center between January 2001 and December 2004. Demographic features, RP incidence and grade (RTOG criteria), hospitalization rate, and overall survival (OS) were assessed.

Results:

85 patients who met the selection criteria were analyzed. The demographic features were - males 61%; Caucasians - 54%; African Americans - 38%; history of pulmonary disorder- 41%; NSCLC- 78%; PS- 0,1- 92%; Stage III- 89%. The median dose of TR was 5940 cGy. Radiation fields have been retrospectively assessed in 41 patients to date. 9 of the 41 patients (22%) received involved field radiation. 53 patients (63%) received Cisplatin/Etoposide and 20 patients (24%) received Carboplatin/Paclitaxel. 75 patients (88%) received concurrent therapy. 31 patients (36%) developed RP; 15 (18%) had RTOG grade ≥ 3 RP. Median time to development of RP was 4.6 months. Rate of RP in females and males was 42% vs. 33% (p=0.49). Rate of RP in patients with history of pulmonary disorder at baseline was 49% as compared to 28% in others (p=0.068). 1 year hospitalization rate was 74% and 37% in RP and non-RP patients (p=0.0015). For all 85 patients, the median overall survival (OS) was 19.5 months (95% CI 16.4 - 23.3). Length of OS did not differ significantly (p = 0.59) between the 31 patients who had RP vs. the 54 patients who had no RP (median OS: 19.3 vs. 18.8 months, respectively). The median survival of the 15 patients who had severe RP was 16.6 months.

Conclusions:

The rate of severe RP in these 85 lung cancer patients, treated off-protocol with CT and TR, is higher than that reported in clinical trials. Despite higher morbidity (i.e., increased hospitalization) in patients with RP, survival duration did not differ significantly by RP status.