Diagnosis and management of drug-associated interstitial lung disease

Abstract

Symptoms of drug-associated interstitial lung disease (ILD) are nonspecific and can be difficult to distinguish from a number of illnesses that commonly occur in patients with non-small-cell lung cancer (NSCLC) on therapy. Identification of drug involvement and differentiation from other illnesses is problematic, although radiological manifestations and clinical tests enable many of the alternative causes of symptoms in advanced NSCLC to be excluded. In lung cancer patients, high-resolution computed tomography (HRCT) is more sensitive than a chest radiograph in evaluating the severity and progression of parenchymal lung disease. Indeed, the use of HRCT imaging has led to the recognition of many distinct patterns of lung involvement and, along with clinical signs and symptoms, helps to predict both outcome and response to treatment. This manuscript outlines the radiology of drug-associated ILD and its differential diagnosis in NSCLC. An algorithm that uses clinical tests to exclude alternative diagnoses is also described.

Figure 1

High-resolution CT images demonstrating radiology of drug-associated ILD. (A) A 77-year-old man with diffuse alveolar damage secondary to amidarone; note the extensive bilateral ground-glass opacities, airspace consolidation and bilateral pleural effusions. (B) A 36-year-old woman with hypersensitivity pneumonitis secondary to sertraline; note the extensive bilateral ground-glass opacities and lobular areas of air trapping (arrows). (C) A 69-year-old man with BOOP-like reaction to amiodarone; note the mild reticulation and bilateral areas of consolidation and ground-glass opacities in a predominantly peribronchial distribution. (D) A 47-year-old man with NSIP reaction to bleomycin; note the extensive bilateral ground-glass opacities with mild superimposed reticulation. (E) A 47-year-old man with eosinophilic pneumonia reaction to dilantin; note the patchy bilateral areas of consolidation involving the peripheral regions of the upper lobes.

Figure 2

Diagnostic algorithm of gefitinib-associated ILD in Japanese patients with NSCLC.