Because small-cell lung cancers grow quickly, they are prone to spreading to other parts of the body (metastasis). They do respond to chemotherapy and radiation treatment, with chemotherapy the favored approach, but in most cases will recur within two years, and become drug-resistant too.
小細胞肺癌由於生長快速，很容易擴散移轉，不過它對於化學治療及放射線治療反應相當敏感，因此通常以化學治療為主。但多數病例在兩年內又會再度復發，並且產生抗藥性。