Earlier this month, a scientist named Eva Ramón Gallegos of the Instituto Politécnico Nacional in Mexico City released the results of a study she and her team have been conducting on HPV (human papillomavirus) and cervical cancer. They used a technique called photodynamic therapy to treat HPV and pre-cancerous lesions on the cervix with staggering results. These lesions are commonly caused by some strains of HPV, or human papillomavirus.
HPV is the single most common sexually transmitted infection (STI) in the US. According to the Office on Women’s Health, part of the US Department of Health and Human Services, around 80 percent of women will be infected with some form of HPV during their lifetime. While the infection does go away on its own in the majority of women, some types of the virus can cause cervical cancer.
There is no cure for HPV. There is a vaccine, which is recommended for all children. Additionally, there are treatments for the genital warts and cervical lesions the virus can cause. One such non-invasive treatment is the photodynamic therapy that Dr. Ramón Gallegos and her team were studying.
Dr. Ramón Gallegos has been studying photodynamic therapy for two decades. The treatment only affects damaged cells, unlike chemotherapy, which kills all cells, including healthy ones. This particular photodynamic therapy involved injecting a drug called delta-aminolevulinic acid into the cervix. After application, the drug transformed into a fluorescent chemical that gathered in the damaged cells but left healthy ones more quickly. After it had left all normal cells, but still remained in damaged ones, doctors exposed the cells to light. The chemical then absorbed the light and killed the affected cells.
The doctor’s results were staggering: In women who had HPV but no cervical lesions, 85 percent were completely cured of the virus. In women who had both HPV and lesions, the cure rate was the same: 85 percent. For women who had lesions but no HPV, the rate was lower, about 42 percent. When the application of delta-aminolevulinic acid was doubled, 100 percent of women with HPV and no lesions were cured.
Photodynamic therapy does have some drawbacks, however. According to the National Cancer Institute, because it must penetrate the skin, it can only be used to treat tumors and lesions that are close to the skin’s surface. Other side effects are minimal. A recent study in the journal Medicine took a close look at the safety and effectiveness of this light therapy. The study’s authors, led by Wenjia Zhang, found that photodynamic therapy dramatically increased the remission rate of those with cervical lesions and HPV. Safety was only slightly compromised, with side effects including burns, scarring, and light sensitivity in the treated area.
More long-term studies are needed to fully understand the efficacy and side effects of Dr. Ramón Gallegos’s specific version of photodynamic therapy, but this is an incredibly encouraging result. Let’s hope it means that there will be a certified cure for HPV soon.