Diagnostic Dilemma in Hydatid Cysts: Tumor-Mimicking Hydatid Cysts.

OBJECTIVES Hydatid cysts are sometimes confused with different pathologies, and problems arise in their diagnosis and treatment. In this study, cases that are followed up with a diagnosis of lung malignancy and that are detected to have hydatid cysts were retrospectively examined. MATERIAL AND METHODS Seven patients with hydatid cysts whose clinical and radiological features were consistent with lung malignancy were retrospectively examined between 2010 and 2014 regarding sex, age, symptoms, diagnostic methods, surgical procedures performed, and postoperative complications. In the diagnosis of the patients, radiological diagnostic methods such as chest radiography, thoracic computed tomography (TCT), and positron emission tomography+computed tomography (PET-CT) as well as invasive diagnostic methods such as bronchoscopy, fine-needle aspiration biopsy, thoracentesis, and video-assisted thoracoscopic surgery were used. RESULTS The average diameter of the lesions was determined as 4.14±1.57 cm in TCT. Maximum standardized uptake value (SUV max) was measured as 8.77±3.41 (5.4-15.1) in the PET-CT analysis. Bronchoscopy, fine-needle aspiration biopsy, and thoracentesis yielded no results. Definitive diagnosis was established by performing thoracotomy and video-assisted thoracoscopic surgery. CONCLUSION Pulmonary hydatid cysts can appear as malignant diseases such as lung cancer as well as infectious pathologies such as tuberculosis or benign pathologies. Radiologically, it should be kept in mind that pulmonary hydatid cysts can mimic many pulmonary pathologies, particularly malignancies. Necessary examinations towards its differential diagnosis must be performed in the preoperative period.