Pancreatic tumors in patients with lung malignancies: A spectrum of clinicopathologic considerations

Objectives: Lung cancer and pancreatic cancer are the most lethal tobacco-associated malignancies. To elucidate possible clinical interrelationships, the authors reviewed the clinicopathologic characteristics of patients treated for both pulmonary and pancreatic neoplasms. Methods: Patients presenting with a potentially resectable pancreatic mass and a diagnosis of metachronous malignant neoplasm of the lung were studied by retrospective chart audit and review of histopathologic material. Results: Seven patients were identified over 6 years, representing five different clinical entities: metachronous presence of lung cancer and pancreatic cancer (n = 3), lung cancer metastatic to the pancreas (n = 1), lung cancer with a benign pancreatic neoplasm (n = 1), periampullary cancer metastatic to the lung (n = 1), and malignant melanoma metastatic to both lung and pancreas (n = 1). A tobacco history was present in all patients but one. Primary treatment modality was complete resection of isolated sites whenever feasible (lung resection, n = 6; pancreatic resection, n = 5). In four cases, a differential diagnosis of adenocarcinomas of both lung and pancreas was obtained after cytokeratin (CK) 7 and CK 20 immunohistochemistry. All patients with evidence of nodal or visceral metastasis from either primary site (n = 4) died within 5 to 9 months after the last operation. Three of four patients who had undergone resection of both pulmonary and pancreatic tumors were alive between 17 and 67 months after the last operation. All three survivors had presented with early disease stages and/or a protracted course (diagnostic interval, 16-66 months). Conclusions: Our experience with neoplastic conditions that can involve lungs and pancreas metachronously may be useful to the clinician who is confronted with a similar situation. If therapeutic decision-making depends on differential diagnostic analysis, examination of CK 20 expression appears to be helpful. Although biologically favorable circumstances are rarely present, long-term survival seems possible after complete operative treatment in selected patients with early-stage disease.