Fungal infection mimicking pulmonary malignancy: clinical and radiological characteristics

The purpose of this study was to evaluate the clinical and radiological features of patients with fungal infection mimicking thoracic malignancy and to establish a diagnostic approach for both clinicians and radiologists to avoid misdiagnosis.

In this retrospective study, we reviewed clinical and computed tomography (CT) findings from 27 patients who presented with suspicion of thoracic malignancy who were ultimately diagnosed with fungal disease.

Patients' median age was 55.7 (range 31-78) years. The most common clinical findings were cough (48.1 %), expectoration (33.3 %), chest pain (25.9 %), weakness (25.9 %), weight loss (18.5 %), and hemoptysis, dyspnea, and fever (7.4 % each). The median lesion size was 35.5 (range 10-85) mm. CT findings included a solid nodule (51.9 %), solid mass (37 %), or both (11.1 %). Nodule and mass margins were lobulated in 9 (33.3 %) patients, ill-defined in 5 (18.5 %), spiculated in 4 (14.8 %), and smooth in 4 (14.8 %) patients. Additional findings included consolidation in 4 (14.8 %) patients, cavitation in 3 (11.1 %), pleural effusion in 2 (7.4 %), and lymphadenopathy in 11 (40.7 %) patients. In all patients, specific diagnoses were made and confirmed by histopathology; final diagnoses were histoplasmosis (25.9 %), coccidiomycosis (22.2 %), cryptococcosis (22.2 %), aspergillosis (14.8 %), North American blastomycosis (7.4 %), mucormycosis (3.75 %), and paracoccidioidomycosis (3.75 %).

Fungal infection can present with clinical and radiological features that are indistinguishable from thoracic malignancy, such as lung nodules or masses. Because the management and outcomes of fungal infection and malignancy are entirely distinct, the establishment of a specific diagnosis is critical to provide appropriate therapy.