Extensive stage small cell lung cancer presenting as an acute perforated appendix: case report and review of the literature.

Malignancies of the appendix are uncommon; a small subset of these lesions are actually metastatic cancers. In some rare cases, these lesions can cause obstruction, appendicitis, and perforation. M.K. is a 54-year-old man who presented to our institution with a 1-day history of right lower quadrant pain and a past medical history significant only for a 75-pack-year smoking history. CT scan revealed a perforated appendix, and the patient was taken to the operating room where a gangrenous appendix was removed uneventfully. Two days post-procedure, the patient was found to have acute mental status changes, requiring intubation and transfer to the surgical intensive care unit. As part of a workup, a CT scan of the head revealed multiple lesions compatible with metastatic disease. At that point, the pathology from the appendix came back as small cell lung cancer. Chest CT revealed hilar adenopathy and a hilar mass. The patient received emergent whole-brain irradiation therapy with improvement in his mental status, allowing him to be extubated and discharged from the hospital within 10 days of admission. Surgeons should remember that an underlying oncologic process may be the etiology of appendicitis in a small but important subgroup of patients.