By Peter West
MONDAY, Nov. 2 (HealthDay News) -- Patients whose melanoma has spread to one or more lymph nodes face a decreased risk of the deadly skin cancer returning if they have radiation treatment following the removal of the nodes, a new Australian study shows.
In a paper to be presented Monday at the American Society for Radiation Oncology annual meeting in Chicago, lead researcher Dr. Bryan Burmeister, a radiation oncologist at Princess Alexandra Hospital in Brisbane, reported the hopeful findings from the five-year study.
"Results of this trial now confirm the place of radiation therapy in the management of patients who have high-risk features following surgery for melanoma involving the lymph nodes," Burmeister said in a news release. "In some institutions, radiation treatment is routine protocol, while in others, the protocol has been either for patients to just be observed or receive some type of adjuvant chemotherapy or immunotherapy. I encourage patients with melanoma to talk to their doctors about whether radiation should be added to their treatment plan."
External beam radiation involves the use of a beam (or beams) of radiation directed through the skin to the cancer and the tissue in its immediate vicinity. This targeted radiation destroys the tumor while helping to mop up nearby cancer cells that might remain after surgery. The therapy is usually painless and performed on an outpatient basis.
Burmeister's study followed 217 patients with melanoma, a deadly skin cancer, between 2002 and 2007. All had at least one lymph node removed after doctors determined that the cancer had spread into the nodes. The surgery, called a lymphadenectomy, is standard treatment for metastasized melanoma.
About half the patients underwent postoperative radiation treatment, while the other half followed-up with their physicians to see if their cancer had returned. By the end of the study, 19 percent of the radiation patients had experienced a local nodal relapse of their melanoma, compared with 31 percent of patients who did not undergo postoperative radiation treatment. Overall survival was not affected, however.
Melanoma starts in the melanocytes, which are cells found in the top layer of skin that are responsible for producing the pigment melanin. Melanoma can arise anywhere there is pigmented tissue, including the eyes, sinuses, anus and a woman's vulva.
According to the Memorial Sloan-Kettering Cancer Center in New York City, skin melanomas often look asymmetrical, have a ragged or blurred border and are dark in color. But rare forms of melanoma contain no pigment and can appear as pink nodules on the skin.
The disease is less common than other skin cancers, but if untreated, melanoma can spread and be difficult to cure. In the United States, more than 67,000 people annually are diagnosed with melanoma, and more than 8,000 will die, according to the American Cancer Society.
Given the severity of the disease, U.S. melanoma experts said they found the study intriguing.
"This is the first randomized study that tested the question whether postoperative radiation therapy offered any advantage in terms of loco-regional control to patients with loco-regionally advanced melanoma," said Dr. Nancy Lee, a radiation oncologist at Memorial Sloan-Kettering. "The authors are to be congratulated for finally completing an important study in our field. This is particularly important as [local] recurrence can be devastating and often is difficult to salvage with additional therapy."
Dr. David Fisher, of Boston's Massachusetts General Hospital, praised the study but said he wanted more data on overall survival.
"This is an important study, since decisive data on the value of adjuvant radiation therapy have been lacking," said Fisher, director of the melanoma program at Mass General. "It will be important to learn additional details, but the study appears to provide important supportive evidence for adjuvant radiation therapy."
The American Cancer Society has more on melanoma and its treatments.