A topical combination therapy may prevent SCC, the second most common form of skin cancer
CANCER DIGEST – Jan. 11, 2025 – A small study has shown that a novel topical treatment for a type of precancerous lesions may prevent the cancer from developing. The results of the trial appear in the Jan. 2, 2025 Journal of Clinical Investigation.
The study involved 18 patients with precancerous skin lesions who underwent a combination treatment using the immunotherapy drug calcipqotriol and the chemotherapy drug fluorouracil (5FU) applied to areas of their bodies with precancerous skin spots. The topical treatment was applied to the face, scalp, and forearms and hands twice a day for six days. All patients were evaluated at a clinic and underwent skin biopsies before treatment, one day after treatment, and eight weeks after treatment.
The researchers led by first author Tomonori Oka, PhD, and senior author Shadmehr Demehri, MD, PhD, at Mass General Brigham Medical Center in Boston, MA designed the trial to find a way to prevent precancerous squamous cell carcinoma (SCC), which is the second most common form of skin cancer. It often first appears as precancerous spots, often caused by sun damage, but removing the spots does not significantly reduce the likelihood of developing SCC over time.
Recently research has found that calcipotriol, a form of vitamin D, combined with the chemotherapy 5-FU can eliminate the spots and prevent recurrence, however, the mechanism of action was not clear. This study showed that the combination therapy activates the patient’s own immune system in a unique way that not only treats the lesions but also prevents the development of cancer.
In this trial the treatment eliminated 95 percent of the precancerous spots on the face and removed all facial lesions in 7 of 10 patients.The treatment cleared 82 percent of scalp spots and 65 and 68 percent of spots on right and left arms and hands. In addition, healthy skin appeared to be unaffected by the treatment.
The researchers studied the skin biopsies under a microscope and discovered that the treatment significantly delayed development of tumors by the activation of immune cells called CD4+ T cells. The researchers continued to follow the patients over five years and found the preventative effect continued over that period.
“This trial demonstrates that immunology can be a powerful force in cancer prevention, much like it transformed cancer treatment over the last decade,” Demehri said in a press release.
Demehri’s team is currently working to launch a clinical trial at multiple cancer centers involving immunocompromised patients, such as organ transplant patients, who are at higher risk of developing skin cancer to see if the treatment can prevent cancer development in these patients.
Sources: Mass General Brigham press release and the Journal of Clinical Investigation
