Patients who receive the standard surgical treatment for melanoma that has spread to one or more key lymph nodes do not live longer, a major new study shows.

The study, published in The New England Journal of Medicine, found that immediately removing and performing biopsies on all lymph nodes located near the original tumor, a procedure called completion lymph node dissection, did not result in increased overall survival rates.

"The new findings likely will result in many fewer of these procedures being performed around the world," said the study's lead author, Mark B. Faries, MD, co-director of the Melanoma Program and head of Surgical Oncology at The Angeles Clinic and Research Institute, an affiliate of Cedars-Sinai. "The results also will likely affect the design of many current and future clinical trials of medical therapies in melanoma."

More than 1,900 patients with melanoma, the deadliest kind of skin cancer, participated in the study conducted at more than 60 medical institutions nationally and internationally. Faries led the research at the John Wayne Cancer Institute in Santa Monica, before joining The Angeles Clinic and Research Institute in April.

The study, among the largest ever conducted on melanoma, examines what Faries describes as the most important question facing physicians and those newly diagnosed with the disease: whether patients who have melanoma cells in a limited number of lymph nodes should undergo extensive surgery to remove all the remaining nodes in that area of the body. The results of the new research suggest they do not.

"This new approach spares patients significant negative side effects and clarifies the road forward in development of additional therapies," said Omid Hamid, MD, chief of Research/Immuno-Oncology, The Angeles Clinic and Research Institute, and co-director, Cutaneous Malignancy Program, Cedars Sinai. "Dr. Faries and colleagues' contribution to the field of surgical oncology cannot be overstated."

Although the completion dissections did not help overall survival, they did have some value, Faries said. By examining the dissected lymph nodes, physicians were able to better gauge how extensively the cancer had spread and to lengthen the time that their patients were disease-free. But those advantages did not translate into longer lives, he explained.

Additionally, nearly 25 percent of the patients who underwent the completion dissections suffered from lymphedema, compared with about 6 percent of the control group, the study found. Lymphedema is swelling that may result when lymph nodes are damaged or removed. Symptoms include hardening of the skin, infections and restricted range of motion.

"This is a larger operation that has a higher risk of complications," Faries said, "including wound infection and nerve damage."

Prior to the now-common sentinel node biopsy procedure, dissection of all regional lymph nodes at the early diagnosis of melanoma was the standard of care. Today, lymphatic mapping techniques are applied worldwide, and the removal of all regional nodes is undertaken only if the sentinel nodes are positive for cancer.

"The larger procedure will remain an option for some patients, but it will no longer be the only 'standard' option," Faries said.

Article: Completion Dissection or Observation for Sentinel-Node Metastasis in Melanoma, Mark B. Faries et al., The New England Journal of Medicine, doi: 10.1056/NEJMoa1613210, published 8 June 2017.