Abstract A36: Predictors of radiation pneumonitis in patients with malignant lung tumors after chemoradiotherapy.
Authors: Gadallah Wafaa 
Published: August 2014

Background: Many patients diagnosed with lung cancer receive chemoradiotherapy (CRT) early in the course of their treatment. High-dose RT is usually delivered to the primary tumor and/or hilar lymph node metastases. This is anticipated to cause pulmonary complications. The reported incidence of radiation pneumonitis has varied widely in clinical studies ranging from 0 to 54%.(1). This wide range is probably the result of differences in the total radiation doses, number of fractions and fraction dose, and the differences in associated chemotherapy regimens.

Aim of the work: To evaluate the association between the clinical, pulmonary function factors and radiation pneumonitis (RP) in patients with locally advanced non-small cell lung cancer (LANSCLC) treated with concurrent chemotherapy and radiotherapy (RT).

Patients and methods: We prospectively reviewed the medical and radiation records of 76 lung cancer patients who were treated consecutively between January 2009 and February 2012 in the Department of Radiation Oncology at Cancer Institute, Assiut University. Patients were included if they had newly diagnosed and pathologically confirmed lung cancer, chemotherapy after thoracic radiotherapy, and availability of both radiographic images, pulmonary function tests and symptom assessment for determining the occurrence of pulmonary toxicity. The clinical and pulmonary function factors were analyzed. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between those factors and RP.

Results: In patients who received chemotherapy as a part of the treatment, of the 76 patients, only 33 (42.5%) patients received induction chemotherapy, 43 (57.5%) received concurrent chemotherapy, The chemotherapy regimens that were used were Cisplatin, Gemcitabine or Navilbin. Median follow-up was 6.5 months (range 6.5-24). Twenty five patients, developed RP, 15 developed grade 2 RP, 8 patients developed grade 3 RP, 1 patient developed grade 4 toxicity, and 1 patient developed grade 5 toxicity. When PFT results were compared between the group of patients who developed pulmonary complication (25 patients) and the group who did not develop pulmonary complication (51 patients) related to CRT there was significant difference in means for FVC, FEV1, and FEV1%.

Univariate analyses showed that chronic obstructive pulmonary disease (COPD) and Forced Expiratory Volume in the first second (FEV1) were associated with RP (p = 0.02). In multivariate analysis, FEV1 value (p = 0.001) and COPD (p = 0.014) were the most significant factors associated with RP. In addition, univariate analyses show that there is not significant difference statistically between the clinical parameters (sex, age, smoking and, induction chemotherapy, concurrent chemotherapy regimens of patients with and without RP.

Conclusions: FEV1 value and COPD are useful indicators for risk of development and predicting RP in NSCLC patients treated with concurrent chemotherapy and RT.

Citation Format: Wafaa Gadallah. Predictors of radiation pneumonitis in patients with malignant lung tumors after chemoradiotherapy. [abstract]. In: Proceedings of the Fifth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2012 Oct 27-30; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(10 Suppl):Abstract nr A36.