This article is more than 5 years old. Information may no longer be current.
SLNB indicated for thick, clinically lymph node-negative melanoma
Click Here to Manage Email Alerts
Patients with thick melanoma who had a negative sentinel lymph node biopsy had prolonged RFS, disease-specific survival and OS, according to study results.
The findings demonstrate the prognostic utility of sentinel lymph node biopsy (SLNB) in these patients and suggest the technique should be indicated for use in this population, researchers wrote.
“The main goal of the current study was to evaluate the usefulness and prognostic value of SLNB in patients with thick melanoma,” Maki Yamamoto, MD, of the division of surgical oncology at the University of California at Irvine Medical Center, told HemOnc Today. “Despite consensus regarding the role of SLNB in patients with intermediate-thickness melanoma, controversy persists concerning those patients with thin (<1 mm) and thick (>4 mm) melanomas.”
Yamamoto and colleagues evaluated data from 571 patients without distant metastases who had melanomas at least 4 mm thick (median Breslow thickness, 6.2 mm; range, 4-25). The median age of patients was 66 years and 70.2% were male.
Forty-six patients presented with clinically lymph node-positive disease and underwent therapeutic lymph node dissection. Another 113 patients did not undergo SLNB, primarily due to medical comorbidities, patient preferences or other considerations (n = 98).
The remaining 412 patients underwent SLNB. Of these patients, 39.1% (n = 161) were found to have a positive sentinel lymph node.
Results of a multivariate analysis indicated a positive SLNB was significantly associated with the presence of satellitosis (OR = 10.31; 95% CI, 1.98-53.83), as well as a primary tumor location in the trunk (OR = 4.6; 95% CI, 2.03-10.42) or an extremity (OR = 3.17; 95% CI, 1.35-7.42) compared with a head or neck location.
Fourteen patients with a negative SLNB developed disease recurrence in the mapped basin, which equated to a 12.3% false-negative rate.
Researchers reported a median RFS of 21.2 months in the entire study population. Median RFS was significantly longer among patients with a negative SLNB (32.4 months) than those with a positive SLNB (14.3 months) or those who presented with clinically lymph node-positive disease (6.8 months; P ˂ .0001 for both).
In the entire cohort, median OS was 42.5 months and median disease-specific survival was 62.1 months.
Patients with a negative SLNB achieved an OS of 53.4 months, which was significantly longer than the 34.7-month median OS among patients with a positive SLNB and the 22-month median OS among patients with clinically positive lymph node disease (P ˂ .0001 for both).
Median disease-specific survival also was significantly longer among patients with a negative SLNB (82.4 months) compared with those with a positive SLNB (41.2 months) or clinically positive lymph node disease (26.8 months; P ˂.0001 for both).
“In our study, patients with thick melanoma and a negative SLNB have significantly prolonged recurrence-free, disease-specific and overall survivals compared with those with a positive SLNB,” Yamamoto said. “SLNB should be considered indicated for patients with thick, clinically lymph node-negative melanoma. One of the next steps could be to refine techniques to decrease the false-negative rate for SLNB in melanoma or to elucidate why some patients may recur distally despite a negative SLNB.”– by Alexandra Todak
Disclosure: The researchers report research funding/honoraria from, speakers bureau roles with and advisory/consultant roles with Amgen, Bristol-Myers Squibb, Delcath, GlaxoSmithKline, IGEA Inc, MabVax, Merck, Myriad Corporation, Navidea, Novartis, OncoSec, Polynoma and Provectus.
Perspective
Back to Top
Giorgos C. Karakousis, MD
Sentinel lymph node biopsy (SLNB) has been well established as a safe staging procedure in patients with intermediate-depth melanomas, and it is routinely recommended for this subset of patients. In patients with thick melanomas — where there may be an appreciable incidence of clinically occult distant disease at presentation — or in patients with thin melanomas, where the overall incidence of regional nodal micrometastases may be low, the role of SLNB is less well defined and the subject of some controversy.In the current study, Yamamoto and colleagues demonstrate a significant association between sentinel lymph node status and prognosis in patients with thick melanomas, adding important results to the existing literature. In a large series of 412 patients with thick melanomas (≥ 4 mm) who underwent SLNB and were treated or evaluated at a single institution, those with positive sentinel lymph nodes demonstrated a significantly worse median disease-specific survival (41.2 months vs. 82.4 months) and OS (34.7 months vs. 53.4 months) compared with those who had negative sentinel lymph nodes. Notably, the rate of sentinel lymph node positivity in this cohort was high (39.1%). Moreover, the rate of false negativity — the rate of subsequent development of clinical nodal disease in the negative sentinel lymph nodal basin computed as a fraction of all patients with regional nodal metastases — was acceptably low at 12.3%.
Subgroup analyses from the final report of the MSLT-1 trial failed to demonstrate differences in OS between patients with thicker (> 3.5 mm) melanomas and micrometastases as identified by SLNB and those who subsequently developed clinical nodal disease in a nodal observation group. The study — along with some smaller retrospective studies — did, however, demonstrate prognostic value for the sentinel lymph nodes technique. The current study, with its larger study population, further importantly reinforces the concept (suggested by the ASCO–Society of Surgical Oncology joint guidelines) that SLNB in patients with thick melanomas can offer significant prognostic information and early regional control of disease to a group of patients with appreciable incidence of regional nodal metastases.
Click Here to Manage Email Alerts