Immunology has been in the forefront and progress in the area of skin cancer — particularly malignant melanoma — and has shown great promise. Melanoma is the sixth-most common cancer in the U.S., and the most common fatal malignancy in young adults.
Currently, about 1 in 50 people will be diagnosed with melanoma. In the 1960s, it was 1 in 600. Surgery is successful when caught early. Otherwise, the five-year survival rate is only about 5 percent.
Two independent studies are being conducted using two different kinds of vaccines developed to treat malignant melanoma.
A Phase I clinical trial using an implantable vaccine was conducted by researchers at the Dana Farber Cancer Institute. This new technology uses a small disk-like sponge made out of FDA-approved polymer material, which is implanted under the skin.
Instead of removing immune cells, then altering them and reintroducing them back into the patient, this disk is designed to find and reprogram the patient's immune cells at the site of the disk, with instructions to then travel to the location of the cancer cells and kill them.
This technology combined the expertise of scientists, engineers and clinicians to develop this novel treatment. In the preclinical study, when this system was studied in mice, 50 percent of the mice treated showed complete tumor regression. The Phase I study is expected to conclude in 2015.
Another vaccine study at Loyola University Medical Center uses a different mechanism and is enrolling patients in its first clinical trial. The vaccine is designed to use the patient's own immune system to attack the cancer.
By genetically modifying killer T cells and then putting them back into the patient, the hope is that the modified T cells will recognize the tumor cells as foreign, attack and kill them. The purpose of this Phase I trial is safety and dosing. If this trial proves successful, an efficacy trial will follow.
Researchers are also turning to gene therapy to identify melanoma-related genes.
Using a highly-sensitive technology called NanoString, researchers at the NCI have identified seven genes, two of which are potentially new candidates for melanoma immunotherapy. The technology allows for the simultaneous measurement of multiple genes that are in higher amounts in tumor cells than in normal cells.
As a result, CSPG4 and SOX10, have been identified as melanoma-related genes. Even though further research is needed to see if these markers can be engineered for use in patients, researchers feel that this is an excellent example of how newer technologies can give cancer researchers and clinicians the best opportunity to make tremendous advancements in cancer research and treatment.
On the diagnostic and therapeutic front, researchers are studying imaging techniques to help identify melanoma lesions and metastases. It was reported in The Journal of Nuclear Medicine, that tumor accumulation correlated melanin content to melanoma metastases. This melanin-targeted radiotracer (123I-BZA2) could theoretically be used to locate metastatic melanoma.
That knowledge could become useful in treatment options, especially in the early stages of the disease, when melanin production is highest. According to Dr. Florent Cachin, M.D., "This strategy nicely illustrates the future of nuclear medicine oncology."
