Researcher questions use of sentinel lymph node biopsy in certain tumors

May 1, 2011

Sentinel lymph node biopsy (SLNB) is commonly considered beneficial for predicting prognosis in patients with cutaneous melanoma, although there has been no documented survival value. A new analysis casts doubt on the value of this practice, however.

Key Points

Chicago - Sentinel lymph node biopsy (SLNB) is commonly considered beneficial for predicting prognosis in patients with cutaneous melanoma, although there has been no documented survival value.

"In my opinion, the only reason for doing a SLNB is possibly to enter a clinical trial," Dr. Rhodes says. "The paper describes why SLNB is not helpful for assessing prognosis. There are no data documenting usefulness of SLNB for melanoma-related survival."

Patient comparisons

In research by Morton et al (Morton DL, et al. N Engl J Med. 2006; 355(13):1307-1317), patients appeared to have a better disease-free survival if they had SLNB followed by therapeutic lymph node dissection if results were positive, versus patients who were observed and had a therapeutic lymph node dissection for clinical recurrence.

"There is no survival difference in those two groups when you compare people who've had positive sentinel node biopsy followed by therapeutic lymphadenectomy compared to patients who've had the excision of the melanoma and just followed," Dr. Rhodes says.

Disease-free survival appears better in patients with a total lymphadenectomy after positive SLNB results, however, because regional lymph node recurrence is included when reporting disease-free survival, he says.

"If your lymph nodes are gone, the first site of metastasis is more likely to be distant," Dr. Rhodes says. "If you have lymph nodes ... usually the first site of recurrence is regional recurrence in those lymph nodes. So it's not fair to include regional lymph node involvement in disease-free survival."

Furthermore, he says, only 20 percent of patients with a positive sentinel lymph node will have other positive nodes after complete lymphadenectomy.

"So that means 80 percent of patients are getting a lymphadenectomy with no benefit, plus the 60 percent chance of complications from the procedure," he says.