Pulmonary Hamartoma, A Relatively Common Diagnosis with a Rare Presentation

Abstract

Abstract Casestudy: Pulmonary hamartomas (PH) are the most common benign tumors of lung, accounting for 75% of all the benign tumors and 8% of all the pulmonary neoplasms. These lung tumors are generally solitary and are observed in middle-aged and older adults with the peak incidence during the sixth decade of life. PH presents as asymptomatic nodule, found incidentally on routine radiographs and CT scans. The majority of PH are located in the lung parenchyma. Endobronchial hamartomas occur much less frequently. An extremely rare presentation of Hamartoma as a mediastinal mass is also reported in the past. The present article reports a case of a 72-year-old female, presented to her primary care physician with the complains of right lower abdominal pain. CT scan of the abdomen and pelvis revealed a partially visualized right paracardiac /mediastinal lipomatous mass. Patient stated that she was informed about a pericardial cyst of about golf ball size, noticed on a routine radiograph 40 years ago. Further workup with CT chest angiography revealed an 8.6 x 5.6 x 5.6 cm mediastinal mass associated with the right heart border and the right cardiophrenic angle, abutting the right diaphragm as well as the medial pleural reflection. A differential diagnosis of teratoma, lipoma/liposarcoma, and hamartoma was considered. Patient underwent robotic assisted surgical resection of the mass which emanated from right lower lung lobe. The histologic features and immunoreactivity pattern were consistent with a benign pulmonary hamartoma. Approximately 90 percent of PH presents as a peripheral intraparenchymal nodule whereas endobronchial hamartoma occurs much less frequently and represents 1.4% - 10 % of PH. A few cases of pulmonary hamartomas presenting as a mediastinal mass have been reported in the past few decades. Here in we report such a case of pulmonary hamartoma presenting as a mediastinal mass.