Cancer Researcher Published in New England Journal of Medicine

By David Robinson

Metastatic Merkel-cell carcinoma is often fatal and there is no effective treatment. Gao’s 86-year-old female patient was diagnosed in 2013 with stage IIIB Merkel-cell carcinoma of the right temple. She had surgery and received radiation therapy in May 2013 and additional surgery in July 2014. In November 2014, doctors confirmed that the cancer had metastasized.

Gao, a dermatologist who treats Merkel-cell carcinoma patients from Arkansas and surrounding states, performed genetics tests on the tumor that revealed multiple mutations, including PI3Kδ.

Gao was aware that the drug idelalisib is a novel PI3K pathway inhibitor approved by the Food and Drug Administration (FDA) for treatment of B-cell lymphoma, a cancer of the blood. She was also aware of recent studies showing that disruption of the PI3Kδ mutation allows the body to mount an effective antitumor immune response.

On the basis of her laboratory work and knowledge of idelalisb, Gao began treatment of the patient with the drug on Feb. 6, 2015. Her findings were published in the Journal in a letter to the editor.

Three months after administering the idelalisib, there was no sign of the tumor in the patient’s liver, Gao said

Based on what she’s learned, Gao said the case can be made for further study of PI3Kδ inhibitors like idelalisib in solid tumors, not just blood cancers.

“The efficacy of idelalisib in our patient provides initial clinical evidence that the targeting of PI3Kδ in Merkel-cell carcinoma is warranted,” Gao said in the letter, which was also signed by UAMS’ Fade Mahmoud, M.D., and Mallory B. Shiver, M.D.

Gao also credits support she received from Peter Emanuel, M.D., director of the UAMS Winthrop P. Rockefeller Cancer Institute, and James Suen, M.D., chair of the Department of Otolaryngology-Head and Neck Surgery in the UAMS College of Medicine.

View the article and accompanying PET-CT findings here.

Gao’s research has been supported by the UAMS Translational Research Institute through the National Institutes of Health National Center for Advancing Translational Sciences, the Department of Dermatology in the UAMS College of Medicine, UAMS Winthrop P. Rockefeller Cancer Institute, and the Arkansas Biosciences Institute.

UAMS is the state's only health sciences university, with colleges of Medicine, Nursing, Pharmacy, Health Professions and Public Health; a graduate school; a hospital; a main campus in Little Rock; a Northwest Arkansas regional campus in Fayetteville; a statewide network of regional campuses; and seven institutes: the Winthrop P. Rockefeller Cancer Institute, Jackson T. Stephens Spine & Neurosciences Institute, Harvey & Bernice Jones Eye Institute, Psychiatric Research Institute, Donald W. Reynolds Institute on Aging, Translational Research Institute and Institute for Digital Health & Innovation. UAMS includes UAMS Health, a statewide health system that encompasses all of UAMS' clinical enterprise. UAMS is the only adult Level 1 trauma center in the state. UAMS has 3,275 students, 890 medical residents and fellows, and five dental residents. It is the state's largest public employer with more than 12,000 employees, including 1,200 physicians who provide care to patients at UAMS, its regional campuses, Arkansas Children's, the VA Medical Center and Baptist Health. Visit or Find us on Facebook, X (formerly Twitter), YouTube or Instagram.