Lung cancer is the most frequent malignant tumour in men. Advanced disease may produce metastatic tumours in subcutaneous tissue and also infiltrate the chest wall. We present a history of a man referred to our department suspected of lung tumour infiltrating the chest wall. Additionally, bone metastatic disease was diagnosed (ribs, vertebral bodies and skull). Thanks to a wide diagnostic approach, ductal cancer of the breast was finally diagnosed, a neoplasm that is extremely rare in male patients, usually presenting as a definite nodule in the nipple area of the breast. This case shows the importance of careful histological evaluation of the chest wall tumour.