The analysis of the outcomes and factors related to iliac–obturator involvement in cutaneous melanoma patients after lymph node dissection due to positive sentinel lymph node biopsy or clinically detected inguinal metastases

Pelvic lymph node dissection in metastatic melanoma to the groin should not be abandoned yet

BACKGROUND

In recent years there has been a plea to abandon the pelvic lymph node dissection in the treatment of patients with metastatic melanoma to the groin. A trend towards a conservative surgical treatment is already evolving in several European countries. The purpose of this study is to identify factors associated with pelvic nodal involvement, in order to improve selection of patients whom might benefit from a pelvic nodal dissection.

METHODS

A retrospective analysis was performed on prospectively collected data concerning patients who underwent an inguinal lymph node dissection (ILND) with pelvic lymph node dissection for metastatic melanoma at the University Medical Center Groningen. Multivariable logistic regression analysis was performed to determine factors associated with pelvic nodal involvement. Diagnostic accuracy was calculated for 18F-FDG PET + contrast enhanced CT-scan and 18F-FDG PET + low dose CT-scan.

RESULTS

Two-hundred-and-twenty-six ILND's were performed in 223 patients. The most common histologic subtype was superficial spreading melanoma (42.6%). In patients with micrometastatic disease, 15.7% had pelvic nodal involvement vs 28.2% in patients with macrometastatic disease (p: 0.030). None of the characteristics known prior to the ILND, were associated with pelvic nodal involvement. Imaging methods were unable to accurately predict pelvic nodal involvement. Negative predictive value was 78% for 18F-FDG PET + low dose CT-scan and 86% for an 18F-FDG PET + contrast enhanced CT-scan.

CONCLUSION

There are no patient- or tumor characteristics available that can predict pelvic nodal involvement in patients with melanoma metastasis to the groin. As no imaging technique is able to predict pelvic nodal involvement it seems unjust to abandon the pelvic lymph node dissection.

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

Background

Patients 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.

Aim

The 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.

Methods

This 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).

Results

Median 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.

Conclusions

Patients 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.

Deep lymph node metastases in the groin significantly affects prognosis, particularly in sentinel node-positive melanoma patients

BACKGROUND

In order to define patients eligible for only a superficial groin dissection or a combined superficial and deep groin dissection, this study aimed to determine the incidence of deep lymph node metastases (LNM) in patients with melanoma metastasized to the groin, to identify patient and melanoma factors that predict deep nodal involvement, and to analyze the impact of deep nodal involvement on survival and recurrence.

METHODS

Patients who underwent a combined superficial (inguinal) and deep (iliac and obturator) complete (CLND) or therapeutic lymph node dissection (TLND) of the groin between 1994 and 2012 were analyzed.

RESULTS

QueryDeep LNM were found in 8 of 62 CLND patients (13 %) and in 21 of 67 TLND patients (31 %). More than three superficial LNM was the only independent predictor for deep LNM in both CLND and TLND patients. The 5-year melanoma-specific survival (MSS) for CLND and TLND patients with deep LNM was 14.3 and 16.6 %, respectively, and was significantly worse (hazard ratio [HR] 3.39, 95 % CI 1.34-8.58, p = 0.010; and HR 2.01, 95 % CI 1.04-3.88, p = 0.039) compared with CLND and TLND patients without deep LNM (5-year MSS: 54.1 and 37.2 %, respectively). Distant recurrence was significantly associated with deep LNM in CLND patients (p = 0.032).

CONCLUSIONS

The present study showed that LNM in the deep area of the groin are fairly common in both CLND and TLND patients and significantly affect prognosis, especially in CLND patients. The number of superficial LNM is the only factor that was found to predict a finding of deep nodal metastases.

Outcomes of routine ilioinguinal lymph node dissection for palpable inguinal melanoma nodal metastasis

BACKGROUND

Patients who present with palpable inguinal melanoma nodal metastasis have two surgical options: inguinal or ilioinguinal lymph node dissection. Indications for either operation remain controversial. This study examined survival and recurrence outcomes following ilioinguinal dissection for patients with palpable inguinal nodal metastasis, and assessed the incidence and preoperative predictors of pelvic nodal metastasis.

METHODS

This was a retrospective clinicopathological analysis of consecutive surgical patients with stage III malignant melanoma. All patients underwent a standardized ilioinguinal dissection at a specialist tertiary oncology hospital over a 12-year period (1998-2010).

RESULTS

Some 38.9 per cent of 113 patients had metastatic pelvic nodes. Over a median follow-up of 31 months, the 5-year overall survival rate was 28 per cent for patients with metastatic inguinal and pelvic nodes, and 51 per cent for those with inguinal nodal metastasis only (P = 0.002). The nodal basin control rate was 88.5 per cent. Despite no evidence of pelvic node involvement on preoperative computed tomography (CT), six patients (5.3 per cent) with a single metastatic inguinal lymph node had metastatic pelvic lymph nodes. Logistic regression analysis showed that the number of metastatic inguinal nodes (odds ratio 1.56; P = 0.021) and suspicious CT findings (odds ratio 9.89; P = 0.001) were both significantly associated with metastatic pelvic nodes. The specificity of CT was good (89.2 per cent) in detecting metastatic pelvic nodes, but the sensitivity was limited (57.9 per cent).

CONCLUSION

Metastatic pelvic nodes are common when palpable metastatic inguinal nodes are present. Long-term survival can be achieved following their resection by ilioinguinal dissection. As metastatic pelvic nodes cannot be diagnosed reliably by preoperative CT, patients presenting with palpable inguinal nodal metastasis should be considered for ilioinguinal dissection.