Calcification within pulmonary lesions usually signifies a benign entity, but depending on the specific pattern of calcification it can also represent malignancy. The authors report a case of calcified small cell lung cancer in a patient with end-stage renal disease. The calcification was unrelated to renal failure and not the result of metastatic calcification, and the pattern of calcification and tissue pathology excluded other causes of calcification within this mediastinal mass.
The presence of calcium in a pulmonary lesion most commonly indicates a benign diagnosis such as a granuloma or hamartoma. Unfortunately, calcification is also seen frequently in certain metastatic lesions, most commonly osteosarcomas. Calcified lung metastases from chondrosarcoma, synovial cell sarcoma, and thyroid, ovarian, breast, and mucinous gastrointestinal cancers have all been reported (1). However, calcification within primary lung cancer is uncommon. One prospective study of 500 patients with a provisional clinical diagnosis of lung cancer who underwent computed tomographic examination of the chest revealed 53 cases (10.6%) of intratumor calcifications (2). Of the reported cases of calcified lung cancer, calcification within small cell lung cancer is rare. We report a case of calcified small cell lung cancer.