Mild pulmonary emphysema a risk factor for interstitial lung disease when using cetuximab for squamous cell carcinoma of the head and neck.

BACKGROUND: Interstitial lung disease (ILD) is an occasionally fatal adverse event associated with cetuximab (Cmab) therapy. Our objective was to clarify to what degree pulmonary emphysema is a risk factor in the treatment of head and neck cancer with Cmab through a retrospective analysis.

METHODS: Subjects were 116 patients who were administered Cmab for head and neck squamous cell carcinoma. The degree of pulmonary emphysema before initiating treatment with Cmab was visually assessed retrospectively, with scoring according to the Goddard classification used in Japanese chronic obstructive pulmonary disease (COPD) guidelines for chest computed tomography (CT). Scoring was conducted by two diagnostic radiologists and mean scores were used. Cutoffs for the development and nondevelopment of ILD were examined by receiver operating characteristic (ROC) analysis and Fisher's exact test. Values of p < .05 were considered to indicate a significant difference.

RESULTS: Among the 116 patients, 11 (9.5%) developed ILD, and 105 (90.5%) did not. In ROC analysis, the optimal Goddard score cut-off of <3.0 offered 55% sensitivity and 81% specificity (p = .015). With a cutoff of <3.0, even very mild pulmonary emphysema would represent a risk factor for ILD when using Cmab.