A case of interstitial pneumonitis associated with Guillain-Barré syndrome during administration of adjuvant trastuzumab.

Optimal treatment for HER2/neu-positive, node-positive early breast cancer should include the monoclonal antibody trastuzumab. This relatively new agent has shown very limited pulmonary toxicity. Our report describes a case of life-threatening interstitial pneumonitis associated with Guillain-Barré syndrome that occurred during the administration of adjuvant trastuzumab. The severity of the clinical presentation and the limited number of reports in the literature of acute trastuzumab-related lung injury make the description of this case of crucial interest.