Predictors and Natural History of In-Transit Melanoma After Sentinel Lymphadenectomy

Survival analysis and clinicopathological factors associated with false-negative sentinel lymph node biopsy findings in patients with cutaneous melanoma

BACKGROUND

We analyzed the outcomes and factors associated with false-negative (FN) results of sentinel lymph node (SLN) biopsy findings in patients with cutaneous melanoma. SLN biopsy failure rate was defined as nodal recurrence in the biopsied regional basin without previous local or in-transit recurrence.

METHODS

Between April 1997 and December 2004, a total of 1207 patients with cutaneous melanoma with a median Breslow thickness of 2.4 mm underwent SLN biopsy by preoperative and intraoperative lymphoscintigraphy combined with dye injection. In 228 cases, we found positive SLNs; of these, 220 underwent completion lymph node dissection (CLND). Median follow-up was 3 years.

RESULTS

The SLN biopsy failure rate was 5.8% (57 of 979 SLN negative). Median time to occurrence of FN relapse after SLN biopsy was 16 months (range, 3-74 months). The FN SLN biopsy results correlated with primary tumor thickness >4 mm (P = .0012), primary tumor ulceration (P = .0002), primary tumor level of invasion Clark stage IV/V (P = .0005), and nodular melanoma histological type (P = .0375). Five-year overall survival, calculated from the date of primary tumor excision, in the FN group was 53.7%, which was not statistically significantly worse than the CLND group (56.8%; P = .9). The FN group was characterized by a higher ratio of two or more metastatic nodes and extracapsular involvement of lymph nodes after LND compared with the CLND group (P < .0001 and P < .0001, respectively). Additional detailed pathological review of FN SLN revealed metastatic disease in 14 patients, which decreased the SLN biopsy failure rate to 4.4% (43 of 979).

CONCLUSIONS

Survival of patients with FN results of SLN biopsy does not differ statistically significantly from that of patients undergoing CLND, although it is slightly lower. The SLN biopsy failure rate is approximately 5.0% in long-term follow-up and is associated mainly with the same factors that indicate a poor prognosis in primary melanoma.

Factors Predicting the Risk of In-Transit Recurrence After Sentinel Lymphonodectomy in Patients With Cutaneous Malignant Melanoma

BACKGROUND

In-transit metastasis is an important morbidity factor after sentinel lymphonodectomy (SLNE). So far, factors posing an increased risk after SLNE have not been adequately analyzed.

METHODS

Using Kaplan-Meier estimations and the Cox proportional hazards model, we analyzed the risk of developing in-transit metastases after SLNE for 328 consecutive patients (median tumor thickness, 2.0 mm; median follow-up period, 40 months).

RESULTS

The 5-year probability of developing in-transit metastases as a first recurrence was 11.2%. After negative and positive SLNE, the probabilities were 6.3% and 24%, respectively. Patients in whom satellite metastases were excised concurrently with the primary tumor had a probability of recurrence with in-transit metastases of 41%. In sentinel lymph node (SLN)-negative patients with primary tumors having a thickness of more than 4 mm, the probability was 22.1%. Among the group of SLN-positive patients, significantly increased in-transit probabilities were observed in those with primary tumors that were thicker than 4 mm (41.8%), with tumors located on the distal extremities (42.1%), and with penetration of the nodal metastasis of >1 mm into the SLN (36%) and in patients with capsular breakthrough (63.3%). By using multifactorial analysis, the SLN status (P = .005), Breslow thickness (P = .0009), and extremity location of the primary melanoma (P = .005) significantly predicted the risk of in-transit recurrence. Satellite metastasis (P < .089), Clark level, and ulceration did not reach significance.

CONCLUSIONS

Subgroups of patients can be identified who seem to have an increased risk of developing in-transit metastases as a first recurrence after SLNE. Individualized therapeutic strategies should be developed for these patients.

Surgical Management of Primary Cutaneous Melanoma: Excision Margins and the Role of Sentinel Lymph Node Examination

Surgical strategies for managing patients who have primary cutaneous melanoma have changed dramatically over the past 30 years. More conservative excision margins have been shown to be adequate, and routine complete lymph node dissection (CLND)has been abandoned since the sentinel node (SN) biopsy technique was introduced. Knowledge of a patient's SN status not only provides a reliable guide to prognosis, but also allows CLND to be avoided in 80% to 85% of patients. Recent clinical trial results suggest that SN biopsy, with immediate CLND if an SN is positive,confers a survival advantage in those who have metastatic disease in regional nodes. Minimally invasive and noninvasive methods of SN assessment, such as magnetic resonance spectroscopy, are being evaluated.

Is there increased risk of local and in-transit recurrence following sentinel lymph node biopsy?

Recent publications have suggested that sentinel lymph node biopsy (SLNB) and completion lymphadenectomy (CLND) increase the rate of local and in-transit disease up to 23% in sentinel node positive group of patients with cutaneous melanoma. This retrospective study combined the data from two national centres on local and in-transit disease in 972 melanoma patients who underwent SLNB procedure over 6.5 years period. In total, 77 patients (7.9%) developed loco-regional recurrence: 41 (4.2%) local recurrence only and 36 patients (3.7%) in-transit metastases during a mean follow-up of 42 months. Patients with positive sentinel lymph node were three times more likely to develop loco-regional metastases than those with no nodal disease (17 vs. 5.6%). Over one third of all recurrences developed following excision of thick (Breslow thickness over 4mm) primary tumours. In both centres age and Breslow thickness were found to be significantly higher in the recurrence group (p<0.001 for both). This study revealed a strong association between increased risk of loco-regional metastases and aggressive tumour biology and adverse patients factors. No conclusive evidence was found to support an increased incidence in patients undergoing SLNB and CLND compared to that published for patients undergoing wide local excision alone.

High positive sentinel node identification rate by EORTC melanoma group protocol. Prognostic indicators of metastatic patterns after sentinel node biopsy in melanoma

Methods to work-up sentinel nodes (SN) vary considerably between institutes. This single institution study evaluated the positive SN-identification rate of the EORTC Melanoma Group (MG) protocol and investigated the prognostic value of the SN status regarding disease-free survival (DFS) and overall survival (OS) and evaluated the locoregional control after the SN procedure. Multivariate and univariate analyses using Cox's proportional hazard regression model was employed to assess the prognostic value of covariates regarding DFS and OS. The positive SN-identification rate was 29% at a median Breslow thickness of 2.00 mm and the false-negative rate was 9.4%. Breslow thickness and ulceration of the primary correlated with SN status. SN status, ulceration and site of the primary tumour correlated with DFS. SN status and ulceration of the primary correlated with OS. The in-transit metastasis rate correlated with SN-positivity, Breslow thickness and ulceration. Projected 3-year OS was 95% in SN-negative and 74% in SN-positive patients. Transhilar bivalving of the SN with step sections from the central planes is simple and had a high SN-positive detection rate of about 30%. The SN status is the most important predictive value for DFS and OS. In-transit metastasis rates correlated with SN-positivity, Breslow thickness and ulceration of the primary.

Does sentinel lymph node biopsy in cutaneous head and neck melanoma alter disease outcome?

BACKGROUND AND OBJECTIVES

In the head and neck region, value, reliability, and safety of sentinel lymph node biopsy (SLNB) have not yet been determined conclusively. The aim of study was to assess impact of SLNB on disease outcome in cutaneous head and neck melanoma.

METHODS

Thirty-six patients with a clinically node-negative head and neck melanoma, > or =1.0 mm Breslow thickness, participated in a prospective study from 1995 to 2005. Sentinel lymph node (SLN) tumor-positive patients underwent completion lymphadenectomy. SLN tumor-negative patients underwent clinical monitoring. Median follow-up was 54 (range 10-114) months. Recurrence-free and overall survival curves were constructed by Kaplan-Meier.

RESULTS

SLNs could be identified in 33 patients (92%). In 7 patients (21%) the SLN was tumor-positive. In 1 patient (13%) the SLNB was false-negative. In 17 patients (47%) SLNs could be identified in the parotid region (success rate parotid region 100%). This study showed no significant difference in recurrence-free and overall survival between patients with tumor-positive and tumor-negative SLN.

CONCLUSIONS

The safety and accuracy of SLNB in the neck and parotid nodal basins were similar to those in non-head and neck sites. However, the technique is technically demanding in this region. In this small series SLNB did not alter disease outcome.