Metastasis of small cell lung carcinoma to the appendix: A case report and literature review

Abstract

Small cell lung cancer (SCLC) is an aggressive tumor with rapid growth and metastasis. Common sites of metastasis include lymph nodes, adrenal glands, liver, bone, and brain, while gastrointestinal metastasis is less and appendicular metastasis is much rarer. Here, we reported a rare case of appendiceal metastasis from small cell lung cancer presented with acute gangrenous perforated appendicitis, periappendiceal abscess and retroperitoneal abscess. The patient, a 63-year-old male, was diagnosed as small-cell lung cancer due to cough, expectoration and blood in sputum. After chemotherapy, local radiotherapy and whole brain prophylactic radiotherapy, the disease progressed continuously and recurred 1 year later, then presented with acute gangrenous perforated appendicitis combined with periappendiceal abscess and retroperitoneal abscess 2 years later. Histopathological and immunohistochemical findings after appendectomy suggested malignant metastasis of small cell lung cancer. Therefore, in the diagnosis and treatment of SCLC cases, SCLC metastasis occurs not only in the common lymph nodes, kidney, adrenal gland, brain, liver, etc., but also in the appendix. This report is expected to provide new guidance for the diagnosis and treatment of such cases.