Researchers at University of California San Diego School of Medicine found an FDA-approved drug used to treat breast cancer has the potential to be an effective therapeutic for a specific type of appendix cancer. The clinical trial results, publishing in the October 16, 2024 online edition of the Journal of Clinical Oncology , showed the oral medication, known as palbociclib, stabilized tumor growth and reduced blood tumor marker levels in patients with peritoneal mucinous carcinomatosis (PMC). This form of cancer originates in the appendix and is often resistant to standard chemotherapy.

"Finding that a breast cancer drug is successful in treating a subset of appendix cancer -; where treatment options are currently limited -; marks a significant advancement in our fight against this disease," said co-senior author Andrew Lowy, MD, professor in the Department of Surgery and chief of the Division of Surgical Oncology at UC San Diego School of Medicine and clinical director for cancer surgery at Moores Cancer Center at UC San Diego Health. "This breakthrough introduces the first targeted therapy for this rare cancer." Appendix cancer is extremely uncommon, accounting for less than 1% of all gastrointestinal cancers, with the American Cancer Society estimating fewer than 2,000 cases diagnosed in the U.

S. each year. The study cohort involved 16 participants diagnosed with PMC, most of whom had previously received other treatments without success.

Researchers analyzed the genetic .