In a recent study, it was proved that immunotherapy drug ‘pembrolizumab‘ responds better than conventional chemotherapy, in case of skin cancer ‘Markel cell carcinoma’, a type of skin cancer.
Merkel cell carcinoma (MCC), is a rare and aggressive type of skin cancer, can be treatable if caught early. Tumors often respond to chemotherapy by shrinking, but only for a short time after which they start growing again.
Merkel cells are located in the outermost layer of the skin and are primarily known as touch receptors. Merkel cell tumors majorly begin on sun-exposed parts of the body, such as face and neck. Their shape and color are less distinctive than other skin cancers, so people usually only notice them after a long time because of rapid growth. It occurs in older people and those who have weak immune systems.
Nearly 80 percent of Merkel cell carcinomas are caused by a virus called the ‘Merkel cell polyomavirus‘. The disease is diagnosed in 1,500 people each year in the United States, and in about 10% of those people, it has already spread.
For initiating this study, investigators from the Bloomberg-Kimmel Institute joined hands with researchers from the Fred Hutchinson Cancer Research Center in Seattle, along with 11 other U.S. medical centers. The Bloomberg~Kimmel Institute team comprise Topalian, William Sharfman, M.D., Evan Lipson, M.D., Abha Soni, D.O., M.P.H., and Janis Taube, M.D., M.Sc.
The study, initiated by Suzanne Topalian, M.D., associate director of the Bloomberg-Kimmel Institute for Cancer Immunotherapy at the Johns Hopkins Kimmel Cancer Center, is the longest observation to date of Merkel cell carcinoma patients treated with any anti-PD-1 immunotherapy drug used in the primary treatment.
The research, published in the Journal of Clinical Oncology, supported the recent (Dec. 19, 2018) U.S. Food and Drug Administration approved of pembrolizumab, marketed as Keytruda, as a primary treatment for adult and pediatric patients with advanced ‘Merkel cell carcinoma’.
The study was conducted over 50 patients with pembrolizumab who had recurrent, locally advanced or metastatic Merkel cell carcinoma. More than half of the patients i.e 28 patients (56 percent) had long-lasting responses to the treatment, 12 people (24 percent) experienced a complete disappearance of their tumors. About 70 percent of patients were alive for two years after starting the treatment.
“This has been such an encouraging development for this disease. When I first started treating people with Merkel cell carcinoma at MSK, the only thing I had to offer them was chemotherapy, and I knew how limited the benefit would be. It is great to have immunotherapy that’s available to block tumor growth and potentially allow people to live longer.”, said Memorial Sloan Kettering medical oncologist Sandra D’Angelo.
Researchers said treatment with pembrolizumab worked well against both virus-positive and virus-negative Merkel cell carcinomas, resulting in high response rates and durable progression-free survival in both subtypes. The research showed that tumors expressing a PD-1-related protein called PD-L1 were likely to respond longer and better to the treatment, although patients whose tumors did not express PD-L1 also responded.
Study says that patients who respond to immune therapy tend to continue their responses for longer time span. Unfortunately, 28 percent of patients experienced serious side effects, including death.