Patients with both melanoma of the skin and positive
lymph nodes may suffer regional relapse after lymphadenectomy, according to a report in the Annals of Surgical Oncology
(8:109-115, 2001). The report cites a study by John Gibbs, md, and colleagues
in the department of surgery at Roswell Park Cancer Institute (RPCI) that
determined the factors that put patients at risk for regional recurrence. The
results have led RPCI to recommend lymph node mapping and sentinel lymph node
biopsy to identify patients with microscopic disease. These results may have
implications for adjuvant treatment decisions, choice of clinical trials, and
progressive approaches that affect the results of sentinel lymph node biopsy.
The study evaluated the risk factors for locoregional recurrence
and clinical outcome in 338 cutaneous malignant melanoma patients treated at
RPCI between January 1970 and December 1996. The patients, who had
microscopically and macroscopically involved lymph nodes, were treated with
either elective or therapeutic lymph node dissection (LND) and without adjuvant
Traditionally, there has been no controversy about the need for
therapeutic LND of the regional nodal basin draining the site of the primary
tumor in patients with obviously involved lymph nodes. The controversy was
whether there was any survival advantage in performing elective LND in patients
with no obvious disease," according to Dr. Gibbs. "The advent of
lymphatic mapping and sentinel lymph node biopsy has changed that."
Risk Factors Identified
In the RPCI study, regional recurrence occurred in 14% of the
patients treated with elective LND and 28% of those treated with therapeutic
LND. Advanced age, head and neck primary, depth of primary lesion, number of
involved lymph nodes, and the higher incidence of extracapsular extension were
identified as risk factors associated with nodal recurrence in the study
population. The 10-year disease-free survival was 51% for the elective LND
group, compared to 30% for the therapeutic LND group. Also, regional failure was
predictive of distant metastasis in 87% of the patients, compared to 54% of
patients without nodal recurrence. The study found that few patients presented
with isolated nodal recurrence, but that most of those who did could be treated
successfully with a second procedure.
"The results of this study are consistent with literature
describing relapse rates after therapeutic, elective, and the current selective
lymph node dissection performed after positive sentinel lymph node biopsy as
well as prognostic factors associated with the development of nodal
recurrence," Dr. Gibbs noted.
The authors point out that despite reports of the significant
incidence of nodal failure following regional lymphadenectomy for melanoma (up
to 52%), few studies have attempted to address the means of improving regional
control. They conclude that preventing initial failure by using the risk factors
identified to stratify patients by low and high probability for recurrence
should be the priority.
"Nodal recurrence frequently heralds systemic disease and a
dismal prognosis," said Dr. Gibbs. "Thus, every attempt should be made
to control stage III disease when it is microscopic, through lymphatic mapping
and SLNB for high-risk patients, and adjuvant radiation therapy for patients
with four or more positive lymph nodes or extracapsular extension."