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

Using a Clinicopathologic and Gene Expression (CP-GEP) Model to Identify Stage I-II Melanoma Patients at Risk of Disease Relapse

Background: The current standard of care for patients without sentinel node (SN) metastasis (i.e., stage I−II melanoma) is watchful waiting, while >40% of patients with stage IB−IIC will eventually present with disease recurrence or die as a result of melanoma. With the prospect of adjuvant therapeutic options for patients with a negative SN, we assessed the performance of a clinicopathologic and gene expression (CP-GEP) model, a model originally developed to predict SN metastasis, to identify patients with stage I−II melanoma at risk of disease relapse. Methods: This study included patients with cutaneous melanoma ≥18 years of age with a negative SN between October 2006 and December 2017 at the Sahlgrenska University Hospital (Sweden) and Erasmus MC Cancer Institute (The Netherlands). According to the CP-GEP model, which can be applied to the primary melanoma tissue, the patients were stratified into high or low risk of recurrence. The primary aim was to assess the 5-year recurrence-free survival (RFS) of low- and high-risk CP-GEP. A secondary aim was to compare the CP-GEP model with the EORTC nomogram, a model based on clinicopathological variables only. Results: In total, 535 patients (stage I−II) were included. CP-GEP stratification among these patients resulted in a 5-year RFS of 92.9% (95% confidence interval (CI): 86.4−96.4) in CP-GEP low-risk patients (n = 122) versus 80.7% (95%CI: 76.3−84.3) in CP-GEP high-risk patients (n = 413; hazard ratio 2.93 (95%CI: 1.41−6.09), p < 0.004). According to the EORTC nomogram, 25% of the patients were classified as having a ‘low risk’ of recurrence (96.8% 5-year RFS (95%CI 91.6−98.8), n = 130), 49% as ‘intermediate risk’ (88.4% 5-year RFS (95%CI 83.6−91.8), n = 261), and 26% as ‘high risk’ (61.1% 5-year RFS (95%CI 51.9−69.1), n = 137). Conclusion: In these two independent European cohorts, the CP-GEP model was able to stratify patients with stage I−II melanoma into two groups differentiated by RFS.

Mesenchymal-epithelial transition factor (MET) immunoreactivity in positive sentinel nodes from patients with melanoma

OBJECTIVE

Patients with cutaneous melanoma and a positive sentinel node (SN) are currently eligible for adjuvant treatment with targeted therapy and immune checkpoint inhibitors. Near-infrared (NIR) fluorescence imaging could be an alternative and less invasive tool for SN biopsy to select patients for adjuvant treatment. One potential target for NIR is the mesenchymal-epithelial transition factor (MET). This study aimed to assess MET immunoreactivity in positive SNs and to evaluate its potential diagnostic, prognostic and therapeutic value.

METHODS

In this retrospective study, positive SN samples from patients with primary cutaneous melanoma were collected to assess MET immunoreactivity. To this end, paraffin-embedded SNs were stained for MET (monoclonal antibody D1C2). A 4-point Histoscore was used to determine cytoplasmic and membranous immunoreactivity (0 negative/1 weak/2 moderate/3 strong). Samples were considered positive when ≥10% of the cancer cells showed MET expression (staining intensity ≥1). Patient and clinicopathological characteristics were used for descriptive statistics, binary logistic regression, and survival analyses.

RESULTS

Positive MET immunohistochemistry was observed in 24 out of 37 samples (65%). No statistically significant associations were found between MET positivity and the following prognostic factors: Breslow thickness (P = 0.961), ulceration (P = 1.000), and SN tumor burden (P = 0.792). According to MET positivity, Kaplan-Meier curves showed no significant differences in survival.

CONCLUSION

This exploratory study found no evidence to support MET immunoreactivity in positive SNs as a possible diagnostic or prognostic indicator in patients with melanoma.

The EORTC protocol for sentinel lymph node biopsy (SLNB) reveals a high number of nodal nevi and a strong association with nevus-associated melanoma

BACKGROUND

The diagnosis of nodal nevi (NN) is challenging as they mimic melanoma metastases (MM), with a detection rate mostly ranging between 1% and 11% in sentinel lymph node biopsy (SLNB). Herein, we assessed the incidence of NN and the association with the clinical-pathological features of primary melanoma, adopting the updated European Organisation for Research and Treatment of Cancer (EORTC) protocol for SLNB.

METHODS

All cases of paired melanoma and SLNB were retrospectively evaluated (April 2019-May 2020). Appropriate statistical tests were adopted, with significant variables included in the logistic regression model.

RESULTS

81 patients and a total of 186 lymph nodes (LNs) were included. Eleven patients had only NN and 4 had both NN and MM (18.5%); 29 LNs (15.6%) showed at least one NN and 12 (6.5%) showed more than one NN (a total amount of 43 NN was detected). All NN and none MM stained for p16. NN were associated with age < 60 years (p: 0.042), no ulceration (p: 0.025) and nevus-associated melanoma (NAM) (p: 0.018), with this latter being the only predictor at the logistic regression model (p: 0.022).

CONCLUSIONS

The updated EORTC protocol shows a high number of NN and highlights a strong association with NAM.

Hematoxylin and eosin or double stain for CD34/SOX10: Which is better for the detection of lymphovascular invasion in cutaneous melanoma?

BACKGROUND

Lymphovascular invasion (LVI) is considered an unfavorable prognostic factor in cutaneous melanoma (CM). However, its detection by hematoxylin and eosin (H&E) is challenging, with discordant data about its association with clinical-pathological features and no previous studies investigating the inter- (IrOA) and intra-observer (IaOA) agreement. Herein, we tested H&E and double staining (DS) for CD34/SOX10 to detect the LVI in a cohort of 92 CMs, evaluating the IrOA, the IaOA, and the association with the other clinical-pathological features.

METHODS

Five authors independently evaluated 92 consecutive and retrospectively enrolled cases of CMs. We assessed the IrOA (Fleiss's Kappa/FK and intraclass correlation coefficient/ICC) and the IaOA (Cohen's Kappa/CK) with both H&E and CD34/SOX10. Furthermore, we compared the LVI assessment with the two stains and analyzed the association with other clinical-pathological features [χ2 tests for dichotomous and categorical data; Student t-test (normal distribution) and Mann-Whitney U-test (non-normal distribution) for continuous data].

RESULTS

The IrOA was almost identical with H&E (FK=0.446; ICC=0.805) and CD34/SOX10 (FK=0.454; ICC=0.810); by contrast, the IaOA was higher with H&E for one pathologist (CK: 0.809) and with CD34/SOX10 for the other one (CK: 0.563). Applying previously defined criteria, LVI was detected in 10 (9.2%) and 11 (10.1%) cases with H&E and CD34/SOX10, respectively (p = 1.000). Both H&E and CD34/SOX10 were significantly associated with vertical growth phase (H&E, p: 0.014; CD34/SOX10, p: 0.010), mitosis ≥ 1/mm2 (H&E, p: 0.000; CD34/SOX10, p: 0.004), pT (H&E, p: 0.000; CD34/SOX10, p: 0.001), Breslow thickness (H&E, p: 0.000; CD34/SOX10, p: 0.001), and lymph node and/or distant metastasis (H&E, p: 0.005; CD34/SOX10, p: 0.000); only H&E was associated with ulceration (p: 0.002) and distant metastasis (p: 0.000), conversely, only CD34/SOX10 was associated with lymph node metastasis (p: 0.003).

CONCLUSIONS

CD34/SOX10 does not improve the IrOA and the IaOA of the LVI assessment in CM; furthermore, H&E and CD34/SOX10 show a similar profile of association with the other unfavorable clinical-pathological features of CM. As result, CD34/SOX10 could be a redundant diagnostic tool if applied for the prognostic characterization of not-selected CM in a routine diagnostic scenario.

Comparison of Two Rapid Assays for the Detection of BRAF V600 Mutations in Metastatic Melanoma including Positive Sentinel Lymph Nodes

Testing for the BRAF mutation is mandatory for the management of patients with locally advanced or metastatic melanoma. Molecular analysis based on DNA sequencing remains the gold-standard method for the screening of the different BRAF mutations. These methods must be rapid, sensitive, and specific enough to allow optimal therapeutic management in daily practice and also to include patients in clinical trials. Here, we compared the Idylla BRAF Mutation Test and the anti-BRAF V600E (clone VE1) immunohistochemistry (IHC) in 90 melanoma samples, with a focus on a challenging cohort of 32 positive sentinel lymph nodes. The BRAF status was assessed with both methods independently of the percentage of tumor cells. The concordance rate was calculated excluding both non-contributory analyses and BRAFV600K/R/M mutants due to the specific V600E-IHC test design. The incidence of the BRAFV600E mutation was 33% with both BRAF Idylla and BRAF IHC. The agreement rate was 91% (72/79). Although the agreement rate was high, we suggest that the use of IHC is more suitable for rapid BRAF testing on sentinel lymph node biopsies when associated with a low percentage and scattered tumor cells, which gave a high risk of non-contributory analysis and/or false negative results with the Idylla^TMBRAF Mutation Test.

Thorny ground, rocky soil: Tissue-specific mechanisms of tumor dormancy and relapse

Disseminated tumor cells (DTCs) spread systemically yet distinct patterns of metastasis indicate a range of tissue susceptibility to metastatic colonization. Distinctions between permissive and suppressive tissues are still being elucidated at cellular and molecular levels. Although there is a growing appreciation for the role of the microenvironment in regulating metastatic success, we have a limited understanding of how diverse tissues regulate DTC dormancy, the state of reversible quiescence and subsequent awakening thought to contribute to delayed relapse. Several themes of microenvironmental regulation of dormancy are beginning to emerge, including vascular association, co-option of pre-existing niches, metabolic adaptation, and immune evasion, with tissue-specific nuances. Conversely, DTC awakening is often associated with injury or inflammation-induced activation of the stroma, promoting a proliferative environment with DTCs following suit. We review what is known about tissue-specific regulation of tumor dormancy on a tissue-by-tissue basis, profiling major metastatic organs including the bone, lung, brain, liver, and lymph node. An aerial view of the barriers to metastatic growth may reveal common targets and dependencies to inform the therapeutic prevention of relapse.

Primary Melanoma Characteristics of Metastatic Disease: A Nationwide Cancer Registry Study

Simple Summary

Melanoma of the skin is the most lethal form of skin cancer. Almost 40% of the patients who die of metastatic melanoma did not have metastases at first diagnosis. More knowledge about patient and tumour characteristics as well as patterns of disease progression is needed. We described the characteristics and disease patterns of early-stage melanomas that progress into metastatic disease. We observed that more than half of the patients with metastases were initially diagnosed with early-stage disease. Additionally, we found that melanomas in some specific body sites were likely to metastasize to certain organs. Our finding that a substantial proportion of patients with metastases were initially diagnosed with early-stage disease highlights the need to investigate who these high-risk patients are.

Abstract

The characteristics and disease patterns of primary stage I and II cutaneous melanomas that progress to stage III or IV disease were investigated based on data from the Netherlands Cancer Registry (NCR). Data on stage III or IV melanomas at first diagnosis or during follow-up between 2017 and 2019 were retrieved. Patient and primary tumour characteristics were investigated in relation to time to disease progression and the number of organ sites with metastatic disease using regression models. In total, 2763 patients were included, of whom 1613 were diagnosed with stage IV disease. Among the patients with stage IV disease, 60% (n = 963) were initially diagnosed with stage I or II disease. The proportion of patients who received a sentinel lymph node biopsy increased after the introduction of adjuvant therapy in 2019 from 61% to 87%. Among all patients with stage III disease who were eligible for adjuvant systemic therapy (n = 453) after 2019, 37% were not treated with this therapy. Among patients with stage IV disease, lung metastases were most often detected as the first metastatic site and females presented with more metastatic sites than males. Most patient and primary tumour characteristics were not associated with the distant metastatic organ site, except melanoma localisation in the lower extremities and the head or neck. Our observation that most stage IV patients were initially diagnosed with early-stage disease highlights the need for more accurate risk prediction models.

The sentinel node invasion level (SNIL) as a prognostic parameter in melanoma

Sentinel lymph node (SN) tumor burden is becoming increasingly important and is likely to be included in future N classifications in melanoma. Our aim was to investigate the prognostic significance of melanoma infiltration of various anatomically defined lymph node substructures. This retrospective cohort study included 1250 consecutive patients with SN biopsy. The pathology protocol required description of metastatic infiltration of each of the following lymph node substructures: intracapsular lymph vessels, subcapsular and transverse sinuses, cortex, paracortex, medulla, and capsule. Within the SN with the highest tumor burden, the SN invasion level (SNIL) was defined as follows: SNIL 1 = melanoma cells confined to intracapsular lymph vessels, subcapsular or transverse sinuses; SNIL 2 = melanoma infiltrating the cortex or paracortex; SNIL 3 = melanoma infiltrating the medulla or capsule. We classified 338 SN-positive patients according to the non-metric SNIL. Using Kaplan-Meier estimates and Cox models, recurrence-free survival (RFS), melanoma-specific survival (MSS) and nodal basin recurrence rates were analyzed. The median follow-up time was 75 months. The SNIL divided the SN-positive population into three groups with significantly different RFS, MSS, and nodal basin recurrence probabilities. The MSS of patients with SNIL 1 was virtually identical to that of SN-negative patients, whereas outgrowth of the metastasis from the parenchyma into the fibrous capsule or the medulla of the lymph node indicated a very poor prognosis. Thus, the SNIL may help to better assess the benefit-risk ratio of adjuvant therapies in patients with different SN metastasis patterns.

Validation of a clinicopathological and gene expression profile model for sentinel lymph node metastasis in primary cutaneous melanoma

BACKGROUND

The Clinicopathological and Gene Expression Profile (CP-GEP) model was developed to accurately identify patients with T1-T3 primary cutaneous melanoma at low risk for nodal metastasis.

OBJECTIVES

To validate the CP-GEP model in an independent Dutch cohort of patients with melanoma.

METHODS

Patients (aged ≥ 18 years) with primary cutaneous melanoma who underwent sentinel lymph node biopsy (SLNB) between 2007 and 2017 at the Erasmus Medical Centre Cancer Institute were eligible. The CP-GEP model combines clinicopathological features (age and Breslow thickness) with the expression of eight target genes involved in melanoma metastasis (ITGB3, PLAT, SERPINE2, GDF15, TGFBR1, LOXL4, CXCL8 and MLANA). Using the pathology result of SLNB as the gold standard, performance measures of the CP-GEP model were calculated, resulting in CP-GEP high risk or low risk for nodal metastasis.

RESULTS

In total, 210 patients were included in the study. Most patients presented with T2 (n = 94, 45%) or T3 (n = 70, 33%) melanoma. Of all patients, 27% (n = 56) had a positive SLNB, with nodal metastasis in 0%, 30%, 54% and 16% of patients with T1, T2, T3 and T4 melanoma, respectively. Overall, the CP-GEP model had a negative predictive value (NPV) of 90·5% [95% confidence interval (CI) 77·9-96.2], with an NPV of 100% (95% CI 72·2-100) in T1, 89·3% (95% CI 72·8-96·3) in T2 and 75·0% (95% CI 30·1-95·4) in T3 melanomas. The CP-GEP indicated high risk in all T4 melanomas.

CONCLUSIONS

The CP-GEP model is a noninvasive and validated tool that accurately identified patients with primary cutaneous melanoma at low risk for nodal metastasis. In this validation cohort, the CP-GEP model has shown the potential to reduce SLNB procedures in patients with melanoma.

Timing of sentinel node biopsy independently predicts disease-free and overall survival in clinical stage I-II melanoma patients: A multicentre study of the Italian Melanoma Intergroup (IMI)

Background

Sentinel lymph node biopsy (SNB) still remains a key procedure to appropriately stage melanoma patients and to select those who are candidate to novel treatments with immunotherapy and targeted therapy in the adjuvant setting. The impact of timing of SNB on disease-free survival (DFS) and overall survival (OS) is still unclear.

Material and methods

The study was conducted at 6 Italian Melanoma Intergroup (IMI) centres and included 8953 consecutive clinical stage I-II melanoma patients who were diagnosed, treated, and followed up between November 1997 and March 2018. All patients were prospectively included in dedicated IMI database. Multivariable Cox regression analyses were performed to investigate how baseline characteristics and time interval until SNB are related to DFS and OS.

Results

Considering the whole population, at multivariable analysis, after adjusting for age, gender, Breslow thickness, site, ulceration, and the SNB status, a delay in the timing of SNB was associated with a better DFS (adjusted hazard ratio [aHR, delayed versus early SNB] 0.98, 95% confidence interval [CI] 0.97–0.99, p < 0.001) and OS (aHR 0.98, 95% CI 0.97–0.99, p = 0.001). Specifically, in patients with a negative SNB status, a beneficial impact of delayed SNB (i.e. at least 32 days after primary excision) was confirmed for DFS (aHR 0.70, 95%CI 0.63–0.79, p < 0.001) and OS (aHR 0.69, 95%CI 0.61–0.78, p < 0.001), whereas in those with a positive SNB status, DFS (aHR 0.96, 95%CI 0.84–1.09, p = 0.534) and OS (aHR 0.94 95%CI 0.81–1.08, p = 0.374) were not significantly different in patients with early or delayed SNB.

Conclusions

Our study does not support a strict time interval for SNB. These results may be useful for national guidelines, for counselling patients and reducing the number of high urgency referrals.

Primary Melanoma: from History to Actual Debates

PURPOSE OF REVIEW

This review describes the long scientific background followed to design guidelines and everyday clinical practice applied to melanoma patients. Surgery is the first option to cure melanoma patients (PTS) at initial diagnosis, since primary cutaneous lesions are usually easily resectable. An excisional biopsy of the lesion, with minimal clear margins, can be obtained in the vast majority of cases. Punch biopsies may be proposed only in case of large lesions located on specific cosmetic or functional areas like the face, extremities, or genitals where a mutilating complete resection would not be performed without prior histological diagnosis.

RECENT FINDINGS

After the histologic confirmation of melanoma, definite surgical excision of the scar and surrounding tissue is planned, to obtain microsatellite free margins. The width of these margins has been identified following the results of several clinical trials and it is either 1 or 2 cm, depending on the Breslow thickness of the primary tumor. Following the latest staging system proposed by the American Joint Cancer commission (AJCC), a sentinel node biopsy (SNB) is usually performed in case of a primary lesion > 0.8 mm thickness or for high-risk thinner lesions, if no evidence of nodal involvement has been identified clinically or radiographically. Surgical management of primary melanoma is well established. There is debate on the optimal surgical margins for 1-2 mm melanomas. There are specific considerations for special primaries (bulky, extremity, mucosal). Sentinel node (SN) evaluation does not improve survival, but is routinely used as staging.

Evolving management of positive regional lymph nodes in melanoma: Past, present and future directions

Sentinel lymph node (SLN) biopsy has become the standard of care for lymph node staging in melanoma and the most important predictor of survival in clinically node-negative disease. Previous guidelines recommend completion lymph node dissection (CLND) in cases of positive SLN; however, the lymph nodes recovered during CLND are only positive in a minority of these cases. Recent evidence suggests that conservative management (i.e. observation) has similar outcomes compared to CLND. We sought to review the most current literature regarding the management of SLN in metastatic melanoma and to discuss potential future directions.

The Role of Completion Lymphadenectomy in Positive Regional Lymph Nodes in Melanoma: A Meta-analysis

BACKGROUND

The optimal management of melanoma with positive sentinel lymph node (SLN) remains unclear. Completion lymph node dissection (CLND) only yields additional positive non-SLN in 20% of cases and its benefits on survival remains debatable.

METHODS

An online database search of Medline was performed; key bibliographies were reviewed. Studies comparing outcomes after CLND versus observation were included. Odds ratios (ORs) with the corresponding 95% confidence intervals (CIs) by random fixed effects models of pooled data were calculated. The primary endpoints were disease-free survival (DFS), melanoma-specific survival (MSS), and overall survival (OS).

RESULTS

Search strategy yielded 117 publications. Twelve studies were selected for inclusion, comprising 7966 SLN-positive patients. Among these patients, 5306 (66.6%) subjects underwent CLND and 2660 (33.4%) patients were observed. Median Breslow thickness and ulceration were similar between groups (2.8 ± 0.6 mm versus 2.5 ± 0.8 mm, P = 0.721; and 38.8% versus 37.2%, P = 0.136, CLND versus observation, respectively). CLND was associated with statistically significant improved 3-y (71.0% versus 66.2%, OR 0.82, 95% CI 0.69-0.97, P = 0.02) and 5-y DFS (48.3% versus 47.8%, OR 0.75, 95% CI 0.59-0.96, P = 0.02) compared with observation. However, no difference was demonstrated in 3-y MSS (83.7% versus 84.7%, OR 1.09, 95% CI 0.88-1.35, P = 0.41), 5-y MSS (68.4% versus 69.8%, OR 1.02, 95% CI 0.88-1.19, P = 0.78), or OS (68.2% versus 78.9%, OR 0.93, 95% CI 0.55-1.57, P = 0.78).

CONCLUSIONS

Based on this large-scale analysis, CLND improved both 3- and 5-y DFS, possibly because of increased rates of local control; however, this did not translate in improved MSS or OS. Efforts toward the identification of molecular markers associated with poor outcomes in SLN-positive patients who undergo observation are warranted.

The long-term prognostic impact of sentinel lymph node biopsy in patients with primary cutaneous melanoma: a prospective study with 10-year follow-up

Purpose

Sentinel lymph node (SLN) biopsy (SLNB) is widely accepted for staging of melanoma patients. It has been shown that clinico-pathological features such as Breslow thickness, ulceration, age, and sex are better predictors of relapse and survival than SLN status alone. The aims of this study were to evaluate the long-term (10-year) prognostic impact of SLNB and to determine predictive factors associated with SLN metastasis, relapse, and melanoma specific mortality (MSM).

Methods

This was a prospective observational study on 289 consecutive patients with primary cutaneous melanoma who underwent SLNB from January 2000 to December 2007, and followed until January 2014, at an Italian academic hospital.

Results

SLN was positive in 64 patients (22.1%). The median follow-up was 116 months (79–147 months). Ten-year disease-free survival and melanoma specific survival were poor in patients with positive SLN (58.7% and 66.4%, respectively). Only the increasing Breslow thickness resulted independently associated to an increased risk of SLN metastasis. Cox regression analysis showed that a Breslow thickness >2 mm was an independent predictor of relapse, and male sex and Breslow thickness >2 mm was a predictor of MSM. At 10 years, SLN metastasis was not significantly associated to either relapse or MSM.

Conclusion

After the fifth year of follow-up, SLN metastasis is not an independent predictive factor of relapse or mortality which are mainly influenced by the characteristics of the primary tumor and of the patient. Patients with a Breslow thickness >2 mm regardless of the SLN status should be considered at high risk for 10-year relapse and mortality.

Gamma probe and ultrasound-guided fine needle aspiration cytology of the sentinel node (GULF) trial

PURPOSE

Sentinel lymph node biopsy (SLNB) was introduced as a minimally invasive technique for nodal staging. Since associated morbidity is not negligible, it is highly relevant to pursue a more minimally invasive alternative. The purpose of this study was to prospectively evaluate the sensitivity of fine needle aspiration cytology (FNAC) with combined gamma probe and ultrasound (US) guidance in comparison with the gold standard histology of the sentinel node (SN) after SLNB for detecting metastasis.

METHODS

The study was designed as a prospective, multicentre, open-label, single-arm trial enrolling patients with newly diagnosed cutaneous melanoma or breast cancer between May 2015 and August 2017. Sample radioactivity was measured using a Mini 900 scintillation monitor. After FNAC, all patients underwent SLNB. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were estimated.

RESULTS

Accrual was terminated early following an unplanned interim analysis indicating that a FNAC sensitivity of at least 80% could not be achieved. In total 58 patients of the originally planned 116 patients underwent FNAC with gamma probe and US guidance. There were no true-positive FNAC results, 14 false-negative results and one false-positive result, and thus the sensitivity, specificity, PPV and NPV of FNAC were 0%, 98%, 0% and 75%, respectively. At least 75% of the FNAC samples had a radioactivity signal higher than the background signal.

CONCLUSION

FNAC with gamma probe and US guidance is not able to correctly detect metastases in the SN and is therefore not able to replace SLNB. Gamma probe-guided US is a highly accurate method for correctly identifying the SN, which offers possibilities for future research.

Use of Lymph Node Ultrasound Prior to Sentinel Lymph Node Biopsy in 384 Patients with Melanoma: A Cost-Effectiveness Analysis

BACKGROUND AND OBJECTIVES

Locoregional lymph node ultrasound is not typically included in guidelines as part of the staging process prior to sentinel lymph node biopsy (SLNB). The objective of the present study was to make a clinical and economic analysis of lymph node ultrasound prior to SLNB.

MATERIALS AND METHODS

We performed a retrospective study of 384 patients with clinical stage I-II primary melanoma who underwent locorregional lymph node ultrasound (with or without ultrasound-guided biopsy) prior to SLNB between 2004 and 2015. We evaluated the reliability and cost-effectiveness of the strategy.

RESULTS

Use of locorregional lymph node ultrasound avoided SLNB in 23 patients (6%). Ultrasound had a sensitivity of 46% and specificity of 76% for the detection of metastatic lymph nodes that were not clinically palpable. False negatives were significantly more common in patients aged over 60 years and in tumors with a thickness of less than 2mm. The staging process using SLNB and ultrasound with ultrasound-guided biopsy produced an increase of €16.30 in the unit price. Our cost-effectiveness analysis identified the staging protocol with ultrasound and SLNB as the dominant strategy, with a lower cost-effectiveness ratio than the alternative, consisting of SLNB alone (8,095.24 vs. €28,605.00).

CONCLUSIONS

Ultrasound with ultrasound-guided biopsy for the diagnostic staging of melanoma prior to SLNB is a useful and cost-effective tool. This procedure does not substitute SLNB, though it does allow to avoid SLNB in a not insignificant proportion of patients.

Sentinel node metastasis mitotic rate (SN-MMR) as a prognostic indicator of rapidly progressing disease in patients with sentinel node-positive melanomas

Risk stratification of sentinel lymph node biopsy (SNB)-positive patients with malignant melanoma differs among current classification systems. To improve classification of patients with rapidly progressive disease who may profit from adjuvant therapy with novel immune or targeted treatment modalities, a single-center retrospective analysis was performed including all melanoma patients diagnosed with a positive SN at a university-based skin cancer center over a 10-year period (2002-2012) (96 of 419 patients). Sentinel node metastasis mitotic rate (SN-MMR) and further histologic parameters were determined by blinded histological re-evaluation and correlated with clinical follow-up (overall [OS], melanoma-specific [MSS], and disease-free survival [DFS]). Median follow-up was 53 months. In univariate analyses, SN tumor penetrative depth (TPD), maximum tumor diameter (MTD), number of positive SN, SN-MMR and the S-, Rotterdam, RDC, Hannover I and II classification systems correlated with OS, MSS and DFS. Multivariate Cox regression analyses showed that a binary classification system based only on the SN-MMR (<1 vs. ≥1 mitoses/mm2 ) was the strongest independent prognostic indicator for all endpoints analyzed. Kaplan-Meier analyses confirmed binary SN-MMR to be superior to stratify patients into high- and low-risk groups (45.45% vs. 87.92% 5-yr MSS). The general prognostic validity of the published SN classification systems was confirmed. The novel SN-MMR classification system may improve discrimination of patients with slowly and rapidly progressive disease. We therefore propose its implementation into clinical practice as the SN-MMR can be easily and reliably determined in routine pathology reports. Its prognostic value for the selection of patients amenable to adjuvant therapies should be studied in clinical trials.

Gamma probe and ultrasound guided fine needle aspiration cytology of the sentinel node (GULF) trial - overview of the literature, pilot and study protocol

BACKGROUND

Sentinel node (SN) biopsy (SNB) detects clinically occult metastases of breast cancer and melanoma in 20-30%. Wound infections, seroma and lymph edema occur in up to 10%. Targeted ultrasound (US) of the SN, (with fine needle aspiration cytology (FNAC) if appropriate) has been investigated as a minimally invasive alternative, but reported sensitivity rates are too low to replace SNB. Our hypothesis is that the use of a handheld gamma probe concomitant with US may improve sensitivity. Our aim is to provide an overview of the current literature on preoperative nodal staging of clinical N0 melanoma patients, report on a pilot, and present a study protocol for a minimally invasive alternative to the SNB: Gamma probe and Ultrasound guided Fine needle aspiration cytology of the sentinel node (GULF trial).

METHODS

The GULF trial is a multicenter open single arm observational trial. Newly diagnosed cT1b-4N0M0 cutaneous melanoma or cT1-3N0M0 breast cancer patients, aged >18 years, presenting for SNB are eligible. 120 patients will be included for preoperative targeted gamma probe guided US and FNAC of the SN. Afterwards all patients proceed to surgical SNB. Primary endpoint is the sensitivity of FNAC. Secondary endpoints include SN identification rate and the histopathological compatibility of Core Needle Biopsy and FNAC vs. SNB. Secondary endpoints were investigated in a pilot with 10 FNACs and marker placements, and 10 FNACs combined with Core Needle Biopsy.

RESULTS

A pilot in 20 patients showed that SN identification rate was 90%, supporting the feasibility of this technique.

DISCUSSION

There is broad experience with US (in combination with FNAC) prior to SNB, but sensitivity and specificity are too low to completely abandon SNB. Promising alternative techniques potentially will replace SNB in the future but more evidence is needed in the form of prospective studies. Accurate identification of the SN for US-FNAC has been proven feasible in our pilot. When adequate sensitivity can be reached, US-FNAC provides a minimally invasive alternative for the surgical SNB procedure.

TRIAL REGISTRATION

The GULF trial is registered in the Netherlands Trial Registry (NTR), ID: NRT5193 . May 1st 2015.

Eight Years' Experience of Sentinel Lymph Node Biopsy in Melanoma Using Lymphoscintigraphy and Gamma Probe Detection After Radiocolloid Mapping

BACKGROUND

Isosulfan blue dye peripheral injection is used in preoperative sentinel lymph node (SLN) identification alone or, to increase sensitivity, in conjunction with radiocolloid mapping. However, isosulfan blue dye has certain drawbacks and limitations.

OBJECTIVE

This study assesses the authors' experience of SLN biopsy using only radiocolloid tracer.

MATERIALS AND METHODS

Between 2000 and 2008, 218 patients underwent SLN biopsy with radiocolloid mapping, preoperative localization by lymphoscintigraphy and intraoperative confirmation by gamma probe in primary malignant cutaneous melanoma.

RESULTS

Mean Breslow index was 2.1 mm. The SLN biopsy success rate was above 98% at all sites and 87% in head and neck locations. The 5-year overall survival rate was 90% and that of 5-year disease-free survival was 80%. False-negative rate, with a mean follow-up time of 41 months, was 5.5%.

CONCLUSION

Sentinel lymph node biopsy can be successfully performed in patients with melanoma using only radiocolloid tracer without blue dye staining. In circumstances where blue dye cannot be used such as head and neck tumors, allergic reactions and pregnancy, radiocolloid tracer mapping alone is not a loss of chance for patients with melanoma.

Exhaustive pathologic work-up in sentinel lymph node biopsy for melanoma: is it necessary?

The objective of this study is to determine whether a less exhaustive pathologic work-up to detect melanoma metastasis is clinically useful and does not affect patient prognosis. The success and evolution of the sentinel lymph node (SLN) depends on histological techniques. Several exhaustive protocols of SLN analysis have been published, but are time and cost consuming, with slight increases in the rates of metastasis detection. From 281 patients with SLN biopsy, each SLN was sectioned every 2 mm and from each paraffin block, 2-3 histological sections were evaluated. The patients were divided as follows: the first group (n=185) was subjected to extensive SLN examination (eSLNe) and the second group (n=96) was not subjected to an extensive SLN examination (wSLNe). The average SLN resected was 2 (range: 1-7), evaluating one in 50.9%. The SLN metastasis detection rate was 28.5%, whereas eSLNe increased by 3.2%. During follow-up, 4/26 (17.4%) cases in the wSLNe group showed recurrence in the SLN basin. Factors associated with decreased survival in univariant analysis were recurrence, Breslow thickness, advanced clinical stage, ulceration, and SLN metastasis. eSLNe did not affect disease-specific survival. Multivariate analysis showed recurrence (hazard ratio 23.475, 95% confidence interval: 1903-4559, P<0.001) and Breslow thickness of more than 3.5 mm (hazard ratio 15.222, 95% confidence interval: 1448-3059, P<0.001) as independent risk factors for decreased survival. Our routine for SLN examination enabled an adequate rate of SLN metastasis detection and the eSLNe increased the rate of detection in 3.2%, but did not affect the survival. We did not find any benefit from performing the eSLNe in patients with Breslow thickness less than 3.5 mm.

Tumor mitotic rate added to the equation: melanoma prognostic factors changed? : a single-institution database study on the prognostic value of tumor mitotic rate for sentinel lymph node status and survival of cutaneous melanoma patients

BACKGROUND

This study aimed to investigate the predictive value of the tumor mitotic rate per mm(2) (TMR) for sentinel lymph node (SLN) status and survival in intermediate and thick cutaneous melanoma.

METHODS

Patients treated for stage I and II melanoma with wide local excision and SLN biopsy between May 1995 and May 2013 were analyzed. In case of insufficient data regarding TMR, pathology slides were reanalyzed. Prognostic factors for SLN status and survival were analyzed with the emphasis on TMR, which was analyzed as a continuous variable, dichotomized (median value) and categorized by two methods.

RESULTS

The study analyzed 453 patients with complete TMR data. The median Breslow thickness was 2.20 mm, and 31.8 % of patients had tumor-positive sentinel lymph node biopsies (SLNBs). In the univariate analysis, TMR was associated with tumor-positive SLNB. This association was not significant in the multivariate analysis. Breslow thickness, primary tumor location on trunk and legs, and younger age were associated with tumor-positive SNLB. At a median follow-up of 47 months, 119 patients (26.3 %) had recurrent disease, and 92 (20.3 %) had died of melanoma. In the univariate analysis, TMR could be established as a significant prognostic factor for disease-free and disease-specific survival, but not in the multivariate analyses. Breslow thickness, ulcerated melanoma, and tumor-positive SLNB were significant prognostic factors for survival.

CONCLUSION

The study was unable to establish TMR as an independent prognostic factor associated with the presence of SLN metastasis. Regarding survival, increasing TMR showed a strong association with decreased survival in the univariate analysis, but this association was rendered nonsignificant by the importance of Breslow thickness and ulceration status in the multivariate model.

Breslow thickness, clark index and ulceration are associated with sentinel lymph node metastasis in melanoma patients: a cohort analysis of 612 patients

BACKGROUND

Sentinel lymph node biopsy (SLNB) is the most sensitive procedure for assessing nodal status in patients with primary melanoma.

OBJECTIVE

To evaluate the predictive ability of usual primary melanoma prognosis factors of detecting sentinel lymph node (SLN) metastasis in patients with melanoma.

PATIENTS AND METHODS

A cohort of 612 consecutive patients presenting with primary skin melanoma who underwent a SLNB was evaluated. Assessment of the determinants of SLN metastasis was based on general linear model analysis. The model performance was studied using the concordance statistic and the net reclassification index. The calibration was estimated using the Hosmer-Lemeshow test.

RESULTS

The discrimination ability did not differ significantly between Breslow thickness (0.57), Clark index (0.61), ulceration (0.57) and histological subtype (0.55). Clark index, ulceration and Breslow thickness were all significant and independent determinants of SLN metastasis. The predictive ability of the final model was 0.657.

CONCLUSION

Breslow thickness, Clark index and ulceration are independent predictors of a SLN metastasis.

Sentinel node biopsy for melanoma. Analysis of our experience (125 patients)

INTRODUCTION

The objective of this study is to analyze our experience in the use of sentinel node biopsy (SNB) in melanoma and identify the predictive factors of positive SNB and multiple drainage.

MATERIAL AND METHODS

Retrospective study of patients who underwent SNB for melanoma between August of 2000 and February of 2013.

RESULTS

SNB was performed in 125 patients with a median of age of 55,6 (±15) years. The anatomic distribution was: 44 (35,2%) in legs, 24 (19,2%) in arms, 53 (42,4%) trunk and 3 (2,4%) in head and neck. The median Breslow index was 1,81 (0,45-5). Between 1 and 6 nodes were isolated. The drainage was unique in 98 (78,4%) and multiple in 27 (21,6%). The trunk was the localization of 25 (92,6%) nodes with multiple drainage. The definitive result of sentinel node (SN) was positive in 18 cases (7,1%). Breslow thickness (p=0,01) was statistically significant predictor of a positive SNB.

CONCLUSIONS

The SNB allows patients to be selected for lymphadenectomy. Melanoma of the trunk was the principle location of multiple drainage. The only predictive factor of positive SNB was Breslow thickness.

The prognostic significance of sentinel node tumour burden in melanoma patients: an international, multicenter study of 1539 sentinel node-positive melanoma patients

INTRODUCTION

Sentinel node (SN) biopsy (SNB) and completion lymph node dissection (CLND) when SN-positive have become standard of care in most cancer centres for melanoma. Various SN tumour burden parameters are assessed to determine the heterogeneity of SN-positivity. The aim of the present study was to validate the prognostic significance of various SN tumour burden micromorphometric features and classification schemes in a large cohort of SN-positive melanoma patients.

METHODS

In 1539 SN-positive patients treated between 1993 and 2008 at 11 melanoma treatment centres in Europe and Australia, indices of SN tumour burden (intranodal location, tumour penetrative depth (TPD) and maximum size of SN tumour deposits) were evaluated.

RESULTS

Non-subcapsular location, increasing TPD and increasing maximum size were all predictive factors for non-SN (NSN) status and were independently associated with poorer melanoma-specific survival (MSS). Patients with subcapsular micrometastases <0.1mm in maximum dimension had the lowest frequency of NSN metastasis (5.5%). Despite differences in SN biopsy protocols and clinicopathologic features of the patient cohorts (between centres), most SN parameters remained predictive in individual centre populations. Maximum SN tumour size>1mm was the most reliable and consistent parameter independently associated with higher non-SN-positivity, poorer disease-free survival (DFS) and poorer MSS.

CONCLUSIONS

In this large retrospective, multicenter cohort study, several parameters of SN tumour burden including intranodal location, TPD and maximum size provided prognostic information, but their prognostic significance varied considerably between the different centres. This could be due to sample size limitations or to differences in SN detection, removal and examination techniques.

Completion lymph node dissection after a positive sentinel node: no longer a must?

PURPOSE OF REVIEW

Sentinel node biopsy (SNB) for primary melanoma is accepted worldwide as a diagnostic procedure. When sentinel node positive, the invasive completion lymph node dissection (CLND) is usually performed. Approximately 20% of CLND patients have nonsentinel node (NSN) metastases. The therapeutic benefit is unknown. This review analyzed the necessity of CLND in sentinel node positive patients.

RECENT FINDINGS

Prognosis of sentinel node positive patients is highly heterogeneous. The Rotterdam and Dewar criteria and S-classification are important sentinel node tumor burden criteria to stratify melanoma patients for prognosis and risk of NSN metastases. Patients with less than 0.1 mm metastases seem to have similar prognosis as sentinel node negative patients, especially when located in the subcapsular area. This depends on the use of an extensive sentinel node pathology protocol identifying possibly clinically irrelevant micrometastases.

SUMMARY

Consensus on the sentinel node pathology work-up and analysis protocols are crucial for correct risk stratification and for clinical decision-making. Primary and sentinel node tumor burden parameters and patient comorbidities should be taken into consideration when offering CLND to an individual patient. In the future, prospective studies such as the MSLT-II and the EORTC 1208 (Minitub) will provide answers to whether CLND has a therapeutic benefit and to which patients might safely be spared CLND.

Preoperative ultrasound is not useful for identifying nodal metastasis in melanoma patients undergoing sentinel node biopsy: preoperative ultrasound in clinically node-negative melanoma

BACKGROUND

Sentinel lymph node biopsy (SLNB) is widely used in melanoma. Identifying nodal involvement preoperatively by high-resolution ultrasound may offer less invasive staging. This study assessed feasibility and staging results of clinically targeted ultrasound (before lymphoscintigraphy) compared to SLNB.

METHODS

From 2005 to 2009, a total of 325 patients with melanoma underwent ultrasound before SLNB. We reviewed demographics and histopathologic characteristics, then compared ultrasound and SLNB results. Sensitivity, specificity, and positive and negative predictive value were determined.

RESULTS

A total of 325 patients were included, 58% men and 42% women with a median age of 58 (range 18-86) years. A total of 471 basins were examined with ultrasound. Only six patients (1.8%) avoided SLNB by undergoing ultrasound-guided fine-needle aspiration of involved nodes, then therapeutic lymphadenectomy. Sixty-five patients (20.4%) had 69 SLNB positive nodal basins; 17 nodal basins from 15 patients with positive ultrasounds were considered truly positive. Forty-five SLNB positive basins had negative ultrasounds (falsely negative). Seven node-positive basins did not undergo ultrasound because of unpredicted drainage. A total of 253 patients with negative SLNBs had negative ultrasounds in 240 nodal basins (truly negative) but falsely positive ultrasounds occurred in 40 basins. Overall, sensitivity of ultrasound was 33.8%, specificity 85.7%, positive predictive value 36.5%, and negative predictive value 84.2%. Sensitivity and specificity improved somewhat with increasing Breslow depth. Sensitivity was highest for the neck, but specificity was highest for the groin.

CONCLUSIONS

Routine preoperative ultrasound in clinically node-negative melanoma is impractical because of its low sensitivity. Selected patients with thick or ulcerated lesions may benefit. Because of variable lymphatic drainage patterns, preoperative ultrasound without lymphoscintigraphic localization will provide incomplete evaluation in many cases.

[Risk factors for in-transit metastasis in patients with cutaneous melanoma]

BACKGROUND

In-transit metastases have been associated with the presence of various negative prognostic factors in patients with cutaneous melanoma. It has recently been suggested that sentinel lymph node biopsy (SLNB) may lead to an increase in the incidence of this particular type of metastasis. In this study, we analyzed risk factors for the appearance of in-transit metastasis and its potential association with the use of SLNB.

MATERIAL AND METHODS

A prospective study was undertaken in a cohort of 404 patients with cutaneous melanoma seen in the melanoma unit of Hospital San Cecilio in Granada, Spain. Statistical analysis was performed with SPSS 15.0 and Epidat 3.1 using the χ(2) and Fisher exact tests.

RESULTS

Out of 93 (23%) patients with recurrence at any time, 28 (6.9%) had in-transit metastases. The occurrence of in-transit metastasis was associated with age greater than 50 years, greater Breslow depth and Clark level, the presence of ulceration, positive SLNB, and the presence of other types of recurrence (local recurrence, lymph node metastasis, or distant metastasis). There was no relationship between surgical treatment or performing SLNB and the presence of in-transit metastasis.

CONCLUSIONS

The risk factors for in-transit metastasis are the same as those for any type of recurrence and coincide with factors linked to poor prognosis. Given that in-transit metastases are much more common in patients with positive SLNB, while the technique itself is not linked to their occurrence, these findings suggest that the appearance of in-transit metastasis is linked to biological characteristics of the tumor cells rather than an influence of the surgical technique.

The clinical use of indocyanine green as a near-infrared fluorescent contrast agent for image-guided oncologic surgery

Optical imaging using near-infrared (NIR) fluorescence provides new prospects for general and oncologic surgery. ICG is currently utilised in NIR fluorescence cancer-related surgery for three indications: sentinel lymph node (SLN) mapping, intraoperative identification of solid tumours, and angiography during reconstructive surgery. Therefore, understanding its advantages and limitations is of significant importance. Although non-targeted and non-conjugatable, ICG appears to be laying the foundation for more widespread use of NIR fluorescence-guided surgery.

Prognosis in patients with sentinel node-positive melanoma is accurately defined by the combined Rotterdam tumor load and Dewar topography criteria

PURPOSE

Prognosis in patients with sentinel node (SN)-positive melanoma correlates with several characteristics of the metastases in the SN such as size and site. These factors reflect biologic behavior and may separate out patients who may or may not need additional locoregional and/or systemic therapy.

PATIENTS AND METHODS

Between 1993 and 2008, 1,080 patients (509 women and 571 men) were diagnosed with tumor burden in the SN in nine European Organisation for Research and Treatment of Cancer (EORTC) melanoma group centers. In total, 1,009 patients (93%) underwent completion lymph node dissection (CLND). Median Breslow thickness was 3.00 mm. The median follow-up time was 37 months. Tumor load and tumor site were reclassified in all nodes by the Rotterdam criteria for size and in 88% by the Dewar criteria for topography.

RESULTS

Patients with submicrometastases (< 0.1 mm in diameter) were shown to have an estimated 5-year overall survival rate of 91% and a low nonsentinel node (NSN) positivity rate of 9%. This is comparable to the rate in SN-negative patients. The strongest predictive parameter for NSN positivity and prognostic parameter for survival was the Rotterdam-Dewar Combined (RDC) criteria. Patients with submicrometastases that were present in the subcapsular area only, had an NSN positivity rate of 2% and an estimated 5- and 10-year melanoma-specific survival (MSS) of 95%.

CONCLUSION

Patients with metastases < 0.1 mm, especially when present in the subcapsular area only, may be overtreated by a routine CLND and have an MSS that is indistinguishable from that of SN-negative patients. Thus the RDC criteria provide a rational basis for decision making in the absence of conclusions provided by randomized controlled trials.

Lymphatic mapping and sentinel lymph node biopsy in patients with melanoma: a meta-analysis

PURPOSE

To perform a meta-analysis of all published studies of sentinel lymph node (SLN) biopsy for staging patients with melanoma.

METHODS

Published literature in all languages between 1990 and 2009 was critically appraised. Primary outcomes evaluated included the proportion successfully mapped (PSM) and test performance including false-negative rate (FNR), post-test probability negative (PTPN), and positive predictive value in the same nodal basin recurrence.

RESULTS

A total of 71 studies including 25,240 patients met full eligibility criteria. The average PSM was 98.1% (95% CI, 97.3% to 98.6%) and increased with the year of publication, female sex, ulceration, age, and the quality score of the studies. The FNR ranged from 0.0% to 34.0%, averaging 12.5% overall (95% CI, 11% to 14.2%). FNR increased with the length of follow-up (P = .002) but decreased with greater PSM (P = .001). PTPN averaged 3.4% (95% CI, 3.0% to 3.8%), which also increased in studies with longer follow-up, younger age, female sex, deeper Breslow thickness, and with tumor ulceration while decreasing with greater PSM (P < .001). Approximately 20% of the patients with a positive SLN had additional lymph nodes in the complete lymph node dissection and 7.5% of the patients with positive SLN developed recurrence in the same nodal basin which was greater in studies that also reported higher FNR (P = .01).

CONCLUSION

The estimated risk of nodal recurrence after a negative SLN biopsy was ≤ 5% supporting the use of this technology for staging patients with melanoma.

Multimarker reverse transcriptase-polymerase chain reaction assay in lymphatic drainage and sentinel node tumor burden

PURPOSE

We assessed molecular (presence of melanoma cells markers in lymph fluid [LY]) and pathological features (sentinel lymph node [SN] tumor burden according to Rotterdam criteria, metastases microanatomic location) and correlated them with survival and melanoma prognostic factors in a group of patients with positive SN biopsy.

METHODS

We analyzed 368 consecutive SN-positive patients after completion lymph node dissection (CLND). In 321 patients we obtained data on SLN microanatomic location/tumor burden (only 7 cases had metastases <0.1 mm); in 137 we additionally analyzed 24-hour collected LY after CLND (multimarker reverse transcriptase-polymerase chain reaction [MM-RT-PCR] with primers for tyrosinase, MART1 (MelanA), and uMAGE mRNA (27.7% positive samples)]. Median follow-up time was 41 months.

RESULTS

According to univariate analysis, the following factors had a negative impact on overall survival (OS): higher Breslow thickness (P = .0001), ulceration (P < .0001), higher Clark level (P = .008), male gender (P = .0001), metastatic lymph nodes >1 (P < .0001), nodal metastases extracapsular extension (P < .0001), metastases to additional non-SNs (P = .0004), micrometastases size ≥ 0.1 mm (P = .0006), and positive LY MM-RT-PCR (P = .0007). SN tumor burden showed linear correlation with increasing Breslow thickness (P = .01). The 5-year OS rates for SLN tumor burden <0.1 mm, 1-1.0 mm, and >1.0 mm were 84%/66%/44%, respectively, and for positive and negative LY MM-RT-PCR 47%/0%, respectively. The independent factors for shorter OS (multivariate analysis): male gender, primary tumor ulceration, number of involved nodes ≥ 4, micrometastases size >1.0 mm, and, in additional model including molecular analysis-positive MM-RT-PCR results (hazard ratio [HR] 3.2), micrometastases size >1.0 mm (HR 1.13), and primary tumor ulceration (HR 2.17). Similar results were demonstrated for disease-free survival (DFS) data.

CONCLUSIONS

SN tumor burden categories according to Rotterdam criteria and the positive result of LY MM-RT-PCR assay demonstrated additional, independent prognostic value in SN-positive melanoma patients, showing significant correlation with shorter DFS and OS.

Importance of tumor load in the sentinel node in melanoma: clinical dilemmas

There are two hypotheses to explain melanoma dissemination: first, simultaneous lymphatic and hematogeneous spread, with regional lymph nodes as indicators of metastatic disease; and second, orderly progression, with regional lymph nodes as governors of metastatic disease. The sentinel node (SN) has been defined as the first draining lymph node from a tumor and is harvested with the use of the triple technique and is processed by an extensive pathology protocol. The SN status is a strong prognostic factor for survival (83-94% for SN negative, 56-75% SN-positive patients). False-negative rates are considerable (9-21%). Preliminary results of the MSLT-1 trial did not demonstrate a survival benefit for the SN procedure, although a subgroup analysis indicates a possible benefit. A mathematical model has demonstrated 24% prognostic false positivity. SN tumor burden represents a heterogeneous patient population and is classified most frequently with the Starz, Dewar or Rotterdam Criteria. A completion lymph-node dissection might not be indicated in all SN-positive patients. Patients classified with metastases <0.1 mm by the Rotterdam Criteria have excellent survival rates. Ultrasound-guided fine-needle aspiration cytology is emerging as a staging tool for high-risk patients, but more research is necessary before this can change clinical practice.

Ratio of marked and excised sentinel lymph nodes and scintigraphic appearance time in melanoma patients with negative sentinel lymph node

AIM

Metastases can occur in up to 15% of all melanoma patients with negative sentinel lymph node examination (SN -). We retrospectively investigated the number of preoperatively marked sentinel lymph nodes (SNs) with lymphoscintigraphy and effectively surgically removed SNs in SN--patients with cutaneous melanoma >or=0.5 mm. Ratio of these parameters was calculated and impact of this ratio as well as impact of scintigraphic appearance time (SAT) on disease progression was studied.

MATERIALS AND METHODS

Data on 122 SN--patients--70 women (58%), mean age 56.5 years--were analyzed. Mean follow-up time was 58 months.

RESULTS

Mean tumour thickness of all patients was 2.3 mm. In 51 patients (42%) the number of SNs marked in lymphoscintigraphy was higher than excised in surgery, in 47 patients (38%) the same number as marked was excised and in 24 patients (20%) a lower number was marked than excised. Metastases occurred in 17 patients (14%) after a mean time of 24.8 months. Mean tumour thickness (5.4 mm) was significantly higher in these patients than in the other patients (p = 0.000). Ratio of marked and excised SNs had no influence on disease progression; the only parameter influencing outcome was tumour thickness (p = 0.000). Short SAT was significantly associated with higher tumour thickness (p = 0.004).

CONCLUSION

Our study indicates that, in routine clinical practice, it suffices to harvest the first SN, as the ratio of marked and excised SNs has no impact on disease progression.