Clinical manifestations of lung cancer

The initial clinical manifestations of lung cancer are diverse and may occur with or without symptoms. Manifestations of pulmonary malignant lesions are produced by local growth or invasion, metastatic disease, or paraneoplastic processes. Patterns of local invasion such as Pancoast's syndrome or the superior vena cava syndrome are relatively uncommon but well recognized. Metastatic lung cancer can involve almost any anatomic area by hematogenous, lymphatic, or, occasionally, interalveolar dissemination. Complications related to malnutrition, infection, electrolyte disturbances, and coexisting diseases influence the initial manifestations. Although individual tumor cell types are associated with characteristic features, no constellation of findings is pathognomonic for a specific histologic variant. Because successful treatment of pulmonary carcinoma depends on early detection, awareness of the typical clinical manifestations is important.