A curious case of exploding cannonball

Pulmonary cavitary lesions with pneumothorax are very common in chest imaging and usually pose diagnostic challenge to clinicians Pneumothorax with a cavitary lesion is a rare occurrence in primary and metastatic lung cancer. A 40-year-old male presented with cough with whitish expectoration, right loin pain, loss of weight and appetite for 3 months and difficulty in breathing for 2 days. Chest x-ray was suggestive of right-side pneumothorax with bilateral nodular opacities in all zones. Contrast-enhanced computed tomography (CECT) thorax and abdomen revealed a non-homogenous large mass in the right kidney with hydronephrotic changes with cavitary lesions in bilateral lungs. Urine cytology was suggestive of urothelial carcinoma. Thus, a diagnosis of urothelial cancer with cavitating metastasis leading to secondary spontaneous pneumothorax was made. Herein, we aim to highlight that cavitating metastasis should be considered in a case of pneumothorax with bilateral lung nodules.