Synchronous primary pulmonary lymphoma presenting with pulmonary adenocarcinoma: A case report and literature review.

The incidence of synchronous lung tumors is rare, as reported in various clinical series, ranging from 0.2% to 8%. Most reported cases of synchronous tumors were shown to have the same histologic types of lung cancer. Among possible combinations, squamous cell carcinoma was by far the most common. Primary pulmonary lymphoma (PPL) is very rare in clinics accounting for only 0.5-1% of primary lung tumors. There is no report about synchronous primary pulmonary adenocarcinoma presenting with lung lymphoma. It can be easily misdiagnosed or missed. Although the treatment of PPL and synchronous pulmonary tumors has controversial, surgery with/without postoperative adjuvant radio-chemotherapy are used for most patients in present. We describe a case of synchronous primary lung tumors presenting with lymphoma and adenocarcinoma, in which expression of the cell surface antigens were evaluated immunohistochemically. By taking into consideration of the reported experiences, the author discusses the clinical features, prognostic criteria and therapeutic management of synchronous lung cancer and PPL.