2. Allergy, Asthma, & Immunology Associates, LTD, Scottsdale, AZ.
3. Rush Medical College, Chicago, IL.
4. Department of Radiation Oncology, Rush University Medical Center, Chicago, IL.
5. Department of Radiation Oncology, Rush University Medical Center, Chicago, IL.
Purpose: We sought to identify factors predictive of development of radiation pneumonitis and pulmonary fibrosis following split course concurrent chemoirradiation for locally advanced non-small cell lung cancer (LA-NSCLC).
Methods and Materials: We reviewed records of 108 patients treated with regimen of split course radiotherapy (median 60 Gy in 30 fractions) and concurrent chemotherapy for stage IIIa/IIIb NSCLC. Fisher's Exact Test and Paired Student T Test were performed to identify factors predictive of development of any pulmonary toxicity (pneumonitis or fibrosis of any grade) and severe pulmonary toxicity (grade 3 or higher pneumonitis, grade 2 or higher fibrosis).
Results: 56 patients (51.2%%) developed any toxicity; 22 patients (20.4%) developed severe toxicity. The following predictive factors were identified for any and severe pulmonary toxicity, respectively: reactive airway disease (RAD), age, RV % expected (EXP), PEF %EXP, FEV1/FVC ratio, smoking status; and RAD, FEV1 %EXP, FVC %EXP, FEV1/FVC %EXP, RV %EXP, FEF25/75 %EXP, PEF %EXP, S-GAW %, FEV1, FVC, and FEV1/FVC .
Conclusions: Our overall rates of any and severe pulmonary toxicity are acceptable. History of RAD and active smoking are protective, whereas patients with severe COPD have increased risk. A trend was seen toward improved outcomes with the use of prophylactic steroid control medication. These results should be confirmed in the context of a prospective study.