Cytomegalovirus tracheobronchitis mimicking lung cancer progression in a patient with lung adenocarcinoma: A case report

Cytomegalovirus (CMV) commonly infects immunocompromised individuals, such as cancer patients. We present a case involving a 60‐year‐old male with Stage 3A lung adenocarcinoma and chronic obstructive pulmonary disease (COPD) diagnosed with CMV tracheobronchitis, initially suspected as cancer progression. Treatment with ganciclovir led to partial improvement in symptoms of shortness of breath and cough, as well as bronchoscopic findings. However, due to ganciclovir‐induced neutropenia, the therapy was switched to foscarnet. Distinguishing between cancer progression and infectious tracheobronchitis through physical examination and chest CT scans remains challenging. In lung cancer patients presenting with airway and bronchial narrowing along with ulcerative mucosal lesions, CMV infection should be considered. A bronchoscopic biopsy is crucial for accurate diagnosis and determining the appropriate treatment in these patients.