Many patients with melanoma need a sentinel-lymph-node biopsy to determine if cancer cells have spread there, but a positive finding doesn't mean all the lymph nodes in the area must be removed, according to a study published in the New England Journal of Medicine (NEJM).
The international study involving 63 centres and more than 3,500 patients suggests any survival advantage associated with removing all the lymph nodes in the area closest to the melanoma is too small to justify the complications patients may suffer from having them removed.
When a biopsy detects melanoma in a sentinel node, standard treatment has been to remove all the nearby nodes, which sometimes triggers complications, explained Tawnya L. Bowles, MD, Intermountain Medical Center, Salt Lake City, Utah.
"It can be a very big deal for patients," she said. "They can have repeat hospitalisations for infections in their extremities. They can have life-limiting, painful swelling where they can't do the activities they like to do or wear their usual clothing. It's a significant, real problem for patients who are affected."
The Multicenter Selective Lymphadenectomy Trial 2 enrolled 3,531 patients who had melanoma. Of those, 1,939 patients had an abnormal sentinel-node biopsy and were randomised to 1 of 2 for further study and treatment.
One group received the standard of care and had all the lymph nodes in the area removed. The other group had ultrasounds of the remaining lymph nodes instead of more surgery. For the first 2 years, they had ultrasounds every 4 months, followed by ultrasounds every 6 months out to 5 years.
In the ultrasound group, if the lymph node got bigger or other abnormalities were detected, a needle biopsy was done to look for melanoma. If it was detected, the other lymph nodes were removed. If the ultrasound was normal over the study period, patients kept all but their sentinel lymph nodes and didn't have more surgery.
The researchers found no significant difference in melanoma-specific survival at 3 years. However, for patients who had those lymph nodes removed, the risk of swelling in the affected arm or leg was four times greater compared with whose lymph nodes were intact.
Some in the group whose lymph nodes were left in place had a recurrence in their lymph nodes. When melanoma recurred in a lymph node, the patients were treated and mortality didn't significantly increase during the study.
Removing the sentinel lymph node for biopsy is of major importance, according to the study authors.
"If the sentinel-node biopsy hadn't been done, the tumour present in the lymph node would have grown and progressed," said Dr. Bowles. "Checking that lymph node is really important, but many patients can be spared taking out the others."
The study raises another question that's yet to be sorted out. With melanoma, immune therapy is often given as an added, or adjuvant, treatment. But most studies of adjuvant therapy have been done in patients who had all their lymph nodes removed after an abnormal sentinel-lymph-node biopsy. That means researchers know how well the therapies work in those patients, but not whether immune therapy results would change if the nodes remain in place. The treatment could be just as effective, but isn't yet proven in clinical studies.
"The question of immune therapy is important, because while removing lymph nodes eliminates the risk that melanoma will spread there, it doesn't stop melanoma from spreading to organs, bones, and distant lymph nodes," Dr. Bowles said. "Patients who die typically die of those distant metastases."
"I hope dermatologists and other healthcare professionals who treat melanoma will understand the sentinel node biopsy is still important, but not all patients need to have follow-up surgery to remove all the other nodes if that sentinel node is positive for melanoma," she said.
Intermountain Healthcare researchers plan to follow the patients in their clinic, looking for 10-year survival and recurrence rates.
"Because we have a large group of patients who were in the ultrasound group, we hope to learn more about their outcomes," said Dr. Bowles. "Did they have immune treatment? How did they do over time? Wère looking forward to continued insights and more advancements in the standard of care for melanoma patients."
SOURCE: Intermountain Medical Center