The Washington University School of Medicine in St. Louis and Harvard Medical School have reported positive results from a clinical study of combination of two topical drugs, cream formulation of topical 5-fluorouracil and calcipotriol, to treat early skin cancer.
Fluorouracil is a type of chemotherapy drug known as anti-metabolites that are similar to normal body molecules with a slightly different structure. It inhibits the cancer cells from making and repairing DNA.
Calcipotriol is a vitamin D3 analog that inhibits cell proliferation and improves differentiation in the skin of patients with psoriasis.
The study enrolled 132 patients with actinic keratosis, 65 of which were randomised to receive the investigational drug combination of 5-fluorouracil plus calcipotriol, while the remaining patients were administered with the standard 5-fluorouracil plus Vaseline petroleum jelly.
Washington University dermatologist and study co-author Lynn Cornelius said: “The idea behind this study was to induce a heightened immune response in the skin, using calcipotriol combined with the 5-fluorouracil that works to destroy the precancerous cells.
“In doing so, the destroyed precancerous cells release cell proteins, or antigens, and facilitate the heightened immune system to respond.
“We compared the two-drug formulation to 5-fluorouracil alone over a shorter application period four days, as opposed to two to four weeks that is typical for the standard treatment of 5-fluorouracil alone.”
Results suggested the efficacy of the investigation topical therapy reduced the number of precancerous skin lesions by almost 88%, compared with a 26% reduction using the standard chemotherapy.
Additionally, the patients previously treated with the conventional therapies reported decreased pain and discomfort with the combination treatment.
Cornelius added: “Because calcipotriol has been shown to induce an immune response, we are now interested in seeing if the anti-tumour immunity of the activated T-cells can be recalled later to help prevent both precancerous and cancerous skin lesions.
“We are now planning to re-contact our patients to determine whether there are differences in precancerous and skin cancer rates between the two treatment groups.”
Image: Lynn Cornelius conducts a skin exam with patient with actinic keratosis. Photo: courtesy of ROBERT BOSTON.