Risk Factors for Positive Deep Pelvic Nodal Involvement in Patients with Palpable Groin Melanoma Metastases: Can the Extent of Surgery be Safely Minimized?

Abstract

BackgroundPatients with palpable melanoma groin metastases have a poor prognosis. There is debate whether a combined superficial and deep groin dissection (CGD) is necessary or if superficial groin dissection (SGD) alone is sufficient.AimThe aim of this study was to analyze risk factors for deep pelvic nodal involvement in a retrospective, multicenter cohort of palpable groin melanoma metastases. This could aid in the development of an algorithm for selective surgery in the future.MethodsThis study related to 209 therapeutic CGDs from four tertiary centers in The Netherlands (1992–2013), selected based on complete preoperative imaging and pathology reports. Analyzed risk factors included baseline and primary tumor characteristics, total and positive number of inguinal nodes, inguinal lymph node ratio (LNR) and positive deep pelvic nodes on imaging (computed tomography [CT] ± positron emission tomography [PET], or PET − low-dose CT).ResultsMedian age was 57 years, 54 % of patients were female, and median follow-up was 21 months (interquartile range [IQR] 11–46 months). Median Breslow thickness was 2.10 mm (IQR 1.40–3.40 mm), and 26 % of all primary melanomas were ulcerated. Positive deep pelvic nodes occurred in 35 % of CGDs. Significantly fewer inguinal nodes were positive in case of negative deep pelvic nodes (median 1 [IQR 1–2] vs. 3 [IQR 1–4] for positive deep pelvic nodes; p < 0.001), and LNR was significantly lower for negative versus positive deep pelvic nodes [median 0.15 (IQR 0.10–0.25) vs. 0.33 (IQR 0.14–0.54); p < 0.001]. A combination of negative imaging, low LNR, low number of positive inguinal nodes, and no extracapsular extension (ECE) could accurately predict the absence of pelvic nodal involvement in 84 % of patients.ConclusionsPatients with negative imaging, few positive inguinal nodes, no ECE, and low LNR have a low risk of positive deep pelvic nodes and may safely undergo SGD alone.

Optimal extent of completion lymphadenectomy for patients with melanoma and a positive sentinel node in the groin

“…The overall pelvic positivity rate was 9⋅3 per cent in this study. In contrast, pelvic positivity rates of approximately 30 per cent have been reported in patients with palpable disease 15,31 . However, even in these patients the extent of surgery does not seem to affect outcome 15 .…”

Extent of Groin Dissection in Melanoma: A Mixed-Methods, Population-Based Study of Practice Patterns and Outcomes

“…Notably absent from the interview results was any mention of the use of Cloquet’s node. In the literature, the deep node positivity rate ranges from 9.3% with microscopically identified disease (i.e., positive sentinel node biopsy) to 55% with macroscopically identified disease (i.e., clinically evident disease) [ 7 , 8 , 9 , 10 , 11 , 12 ].…”

Surgical options in melanoma metastasis in regional lymph nodes

“…Исторически устоявшимися показаниями к их удалению до настоящего времени являлось метастатическое поражение ЛУ Клоке (ЛУ на границе сопряжения бедренного сосудистого пучка и паховой связки) или наличие нескольких пораженных паховых ЛУ из-за высокого риска выявления при таком поражении метастазов в подвздошных ЛУ в ходе последующего морфологического исследования [29][30][31][32]. В целом, по данным различных авторов, при клинически определяемых метастазах меланомы в паховых ЛУ частота поражения подвздошных ЛУ может составлять от 8 до 40 % [33][34][35].…”