Evaluating a Nomogram for the Development of Radiation Pneumonitis

in Locally Advanced Non-Small Cell Lung Cancer Treated with 3D and

Intensity Modulated Radiation TherapySana Rehman, MD1, Christina K. Speirs, MD, PhD1, Alerson Molotievschi, MD2, Daniel Mullen, DDS, MS1, Sandra Fergus BS1, Todd A. DeWees, PhD1, Maria A.

Velez1, Jeffrey D. Bradley, MD1, Cliff G. Robinson, MD1, 1Washington University in St. Louis, St. Louis, MO, 

2Barretos Cancer Hospital, Barretos, Brazil

Session title: Lung 1 – Novel Prognostic Factors and SBRTASTRO 2014 - #57012

Department of Radiation Oncology

Purpose / Methods• Purpose

• Evaluate a previously published nomogram on risk of developing radiation pneumonitis (RP) on a more modern cohort, including patients treated with intensity modulated radiation therapy (IMRT)

• Determine risk factors for development of grade 2 or higher RP

• Methods• Retrospective analysis of 340 patients treated with radiation therapy

for locally advanced non-small cell lung cancer at Siteman Cancer Center from 2001 to 2012.

• Clinical, tumor, and dosimetric information were collected.• Univariate (UVA) and multivariate (MVA) analyses were used to

correlate these factors with the development of ≥ grade 2 RP.• RP risk was determined based on a nomogram prediction for RP.

Spearman’s rank correlation was performed based on the calculated risk of RP versus the actual rate of RP.

Department of Radiation Oncology

Results• 111 patients (35%) developed

grade 2 or higher RP at a median of 3.6 months (range, 0 – 21.9 mo).

• Factors predictive on UVA for grade 2 or higher RP included:• Use of adjuvant chemotherapy• Former smoking status• Heart mean dose• Heart V5-55 Gy (in 5 Gy

increments)• Total lung volume minus PTV

V35-50 Gy (in 5 Gy increments)• RP risk nomogram score

• On MVA, heart V35 Gy was predictive and current smoking status was protective of grade 2 or higher RP.

Department of Radiation Oncology

Conclusion• The dose to the heart is predictive for the risk of RP.• The nomogram for predicting RP is validated for patients

treated with 3DCRT.• The nomogram was not validated for patients treated with

IMRT.