Early (sentinel lymph node biopsy-guided) versus delayed lymphadenectomy in melanoma patients with lymph node metastases: Personal Experience and Literature Meta-Analysis

Ultrasensitive detection of malignant melanoma using PET molecular imaging probes

With the emergence of new therapeutic modalities, the diagnosis of melanoma at the earliest practicable stage has become more important for improving the survival of patients. We developed a positron emission tomography (PET) imaging probe, N-(2-(dimethylamino)ethyl)-5-[¹⁸F]fluoropicolinamide ([¹⁸F]DMPY2) and evaluated diagnostic performance in animal models. [¹⁸F]DMPY2 PET exhibited excellent performance in detecting primary and metastatic melanomas, demonstrating strong/prolonged tumoral uptake and rapid background clearance. This suggests that this radiotracer could be used as a novel PET imaging agent to obtain outstanding image quality in the diagnosis of melanoma. This is the pioneering report of pyridine-based benzamide derivative with reduced alkyl chains in the amine residue and ultrasensitive detection of melanoma lesions in living subjects compared to conventional PET imaging agents.

Malignant melanoma has one of the highest mortality rates of any cancer because of its aggressive nature and high metastatic potential. Clinical staging of the disease at the time of diagnosis is very important for the prognosis and outcome of melanoma treatment. In this study, we designed and synthesized the ¹⁸F-labeled pyridine-based benzamide derivatives N-(2-(dimethylamino)ethyl)-5-[¹⁸F]fluoropicolinamide ([¹⁸F]DMPY2) and N-(2-(dimethylamino)ethyl)-6-[¹⁸F]fluoronicotinamide ([¹⁸F]DMPY3) to detect primary and metastatic melanoma at an early stage and evaluated their performance in this task. [¹⁸F]DMPY2 and [¹⁸F]DMPY3 were synthesized by direct radiofluorination of the bromo precursor, and radiochemical yields were ∼15–20%. Cell uptakes of [¹⁸F]DMPY2 and [¹⁸F]DMPY3 were >103-fold and 18-fold higher, respectively, in B16F10 (mouse melanoma) cells than in negative control cells. Biodistribution studies revealed strong tumor uptake and retention of [¹⁸F]DMPY2 (24.8% injected dose per gram of tissue [ID/g] at 60 min) and [¹⁸F]DMPY3 (11.7%ID/g at 60 min) in B16F10 xenografts. MicroPET imaging of both agents demonstrated strong tumoral uptake/retention and rapid washout, resulting in excellent tumor-to-background contrast in B16F10 xenografts. In particular, [¹⁸F]DMPY2 clearly visualized almost all metastatic lesions in lung and lymph nodes, with excellent image quality. [¹⁸F]DMPY2 demonstrated a significantly higher tumor-to-liver ratio than [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) and the previously reported benzamide tracers N-[2-(diethylamino)-ethyl]-5-[¹⁸F]fluoropicolinamide ([¹⁸F]P3BZA) and N-[2-(diethylamino)-ethyl]-4-[¹⁸F]fluorobenzamide ([¹⁸F]FBZA) in B16F10-bearing or SK-MEL-3 (human melanoma)-bearing mice. In conclusion, [¹⁸F]DMPY2 might have strong potential for the diagnosis of early stage primary and metastatic melanoma using positron emission tomography (PET).

N-(2-(Dimethylamino)Ethyl)-4-18F-Fluorobenzamide: A Novel Molecular Probe for High-Contrast PET Imaging of Malignant Melanoma

Malignant melanoma is an aggressive and serious form of skin cancer, with prognosis and treatment outcome depending heavily on the clinical stage of the disease at the time of diagnosis. Here, we synthesized a novel ¹⁸F-labeled benzamide derivative to target melanoma and then evaluated its biologic characteristics in small-animal models. Methods: N-(2-(dimethylamino)ethyl)-4-¹⁸F-fluorobenzamide (¹⁸F-DMFB) was synthesized by reaction of N-succinimidyl 4-¹⁸F-fluorobenzoate with N,N-dimethylethylenediamine. The binding affinity of ¹⁸F-DMFB was measured in B16F10 (mouse melanoma) cells with or without l-tyrosine. Small-animal PET imaging with ¹⁸F-DMFB was performed on B16F10 xenograft and metastasis mouse models. Results: The overall non-decay-corrected radiochemical yield of ¹⁸F-DMFB was approximately 10%-15%. Uptake of ¹⁸F-DMFB was melanin-specific, as cellular uptake in B16F10 increased more than 18-fold in the presence of l-tyrosine. Biodistribution studies revealed that ¹⁸F-DMFB accumulated, and was retained, in B16F10 xenografts for 120 min (10, 30, 60, and 120 min: 9.24, 10.80, 13.0, and 10.59 percentage injected dose/g, respectively) after radiotracer injection. Liver uptake of ¹⁸F-DMFB decreased from 10 to 120 min and showed fast clearance (10, 30, 60, and 120 min: 11.19, 5.7, 2.47, and 0.4 percentage injected dose/g). Furthermore, ¹⁸F-DMFB allowed visualization of metastatic lesions immediately after injection and was retained in lesions for over 60 min, with a high tumor-to-background ratio. Conclusion: ¹⁸F-DMFB demonstrated a high melanin-targeting ability and tumor-specific tumor uptake in both primary and metastatic lesions in animal models bearing malignant melanoma. ¹⁸F-DMFB may be a potential PET imaging agent for melanoma.

Complications following completion lymphadenectomy versus therapeutic lymphadenectomy for melanoma - A systematic review of the literature

PURPOSE

Completion lymph node dissection (CLND) following a positive sentinel lymph node biopsy (SLNB) has been reported to be less morbid than lymphadenectomy for palpable disease (therapeutic lymph node dissection; TLND). The reporting of morbidity data can be heterogeneous, and hence no 'average' surgical complication rates of these procedures has been reported. This review aims to determine complications rates to inform patients undergoing surgery for metastatic melanoma.

METHODS

A systematic review of English-language literature from 2000 to 2017, reporting morbidity information about CLND and TLND for melanoma, was performed. The methodological quality of the included studies was performed using the methodological index for non-randomised studies (MINORS) instrument and Detsky score. Pooled proportions of post-operative complications were constructed using a random effects statistical model.

RESULTS

After application of inclusion and exclusion criteria, 18 articles progressed to the final analysis. In relation to TLND (1627 patients), the overall incidence of surgical complications was 39.3% (95% CI 32.6-46.2); including wound infection/breakdown 25.4% (95% CI: 20.9-30.3); lymphoedema 20.9% (95% CI: 13.8-29.1); and seroma 20.4% (95% CI: 15.9-25.2). For CLND (1929 patients), the overall incidence of surgical complications was 37.2% (95% CI 27.6-47.4); including wound infection/breakdown 21.6% (95% CI: 13.8-30.6); lymphoedema 18% (95% CI: 12.5-24.2); and seroma 17.9% (95% CI: 10.3-27). The complication rate was marginally lower for CLND but not to statistical significance.

DISCUSSION

This study provides information about the incidence of complications after CLND and TLND. It can be used to counsel patients about the procedures and it sets a benchmark against which surgeons can audit their practice.

Timing of completion lymphadenectomy after positive sentinel node biopsy in patients with melanoma

Background

Nodal staging with sentinel node biopsy (SNB) and completion lymph node dissection (CLND) provides prognostic information to patients with melanoma and their physicians. It is not known whether the timing of CLND is associated with survival outcome and/or CLND tumour load. This study investigated whether CLND timing is associated with CLND tumour load, disease-free survival (DFS) and/or melanoma-specific survival (MSS).

Methods

A retrospective cohort of patients with SNB-positive melanoma from nine European Organisation for Research and Treatment of Cancer (EORTC) Melanoma Group centres undergoing surgery between 1993 and 2009 were examined. Patients were selected based on availability of CLND and follow-up data. The CLND interval was defined as the number of days between diagnosis and CLND. Patient and tumour characteristics were collected. Five-year DFS and MSS rates were calculated. Cox and logistic regression analysis were performed, adjusting for known prognostic/predictive indicators.

Results

A total of 784 patients were included in the study. Their median age was 51 (i.q.r. 40–62) years, and 418 patients (53·3 per cent) were men. Median Breslow thickness was 3·0 (i.q.r. 2·0–5·0) mm, and 148 patients (18·9 per cent) had a residual tumour load. Median CLND interval was 84 (i.q.r. 65–105) days. Five-year DFS and MSS rates were not significantly different for patients operated on with a median CLND interval of less than 84 days and those with an interval of at least 84 days (DFS: 54·2 versus 53·3 per cent respectively; MSS: 66·9 versus 65·1 per cent). In a multivariable Cox model, CLND interval was not a significant prognostic indicator. CLND interval was negatively correlated with identification of positive non-sentinel nodes, but following adjustment for known risk factors this effect was no longer found.

Conclusion

The time interval between diagnosis of melanoma and CLND did not influence CLND tumour load, DFS or MSS.

Treatment outcomes in pediatric melanoma-Are there benefits to specialized care?

PURPOSE

The purpose of this study was to evaluate the impact of hospital specialization on survival in pediatric melanoma.

METHODS

We reviewed all patients under 18years old with cutaneous melanoma evaluated at MD Anderson Cancer Center, a National Cancer Institute (NCI)-designated center, from 2000 to 2014. We compared overall survival (OS) and disease-free survival (DFS) between patients who underwent all treatments at MDACC (Group A, n=146) and those who underwent initial surgical treatment at a non-NCI center (Group B, n=58). Kaplan-Meier survival curves were compared using the log-rank test.

RESULTS

Group A patients had significantly better OS and DFS (both p<0.001). Five-year OS was 97% (95% CI 92%-99%) in Group A versus 88% (95% CI 74%-94%) in Group B. Group survival differences were most notable in Stage 3 and 4 patients. Group A patients presenting with stage III or IV disease had a 5-year OS rate of 91.2% (95% CI 75.1%-97.1%) compared to 80.8% (95% CI 59.8%-91.5%) in Group B. The DFS rate was 94.4% (95% CI 88.5%-97.3%) in Group A versus 77.2% (95% CI 62.5%-86.7%) in Group B.

CONCLUSION

Surgical treatment at a comprehensive cancer center may improve outcomes for pediatric melanoma especially for patients presenting with later stage disease.

LEVEL OF EVIDENCE

Case-control study: Level III.

Sentinel lymph node biopsy plus wide local excision vs. wide location excision alone for primary cutaneous melanoma: a systematic review and meta-analysis

BACKGROUND

Sentinel lymph node biopsy and wide local excision of the primary melanoma (SLNB) is now a standard staging procedure for patients with melanomas 1 mm or more in thickness, but its therapeutic benefit is not clear.

OBJECTIVE

To determine whether there is an association between performance of SLNB and patient prognosis.

METHODS

Studies assessing the association between performance of SLNB and patient prognosis were pooled from MEDLINE, EMBASE, PubMed, Cochrane Database of Systematic Reviews and Google Scholar. From each study, first author's last name, publication year, origin country, type of study design, characteristics of participants and the Hazard risk (HR) for melanoma specific survival (MSS) with the corresponding 95% confidence interval (95% CI) were collected. Methodological assessment of the studies was evaluated using the Newcastle-Ottawa scale (NOS) and the 'Risk of bias' tool detailed in the Cochrane Handbook for Systematic Reviews of Interventions. Meta-analyses for the global HR were performed. In addition, in order to explore the sources of heterogeneity among the studies, sensitivity analyses are also provided.

RESULTS

A total of six studies with 8764 patients who had undergone SLNB and 11054 patients who had undergone wide location excision alone (WLEA) were identified for the analysis. The indicators suggest that the heterogeneity is low: τ²  = 0; H = 1 [1; 1.74]; I²  = 0% [0%; 66.5%]. Evidence for publication bias was not found (Egger's test P = 0.4654). The pooled MSS HR from fixed effects analysis was determined to be 0.88 (95% CI = 0.80-0.96).

CONCLUSIONS

Although no significant survival difference was observed in four of the six series, the pooling summary data from all the studies that deal with this issue suggested that SLNB is associated with a significantly better outcome compared with WLEA for localized melanoma.

Measuring the quality of melanoma surgery - Highlighting issues with standardization and quality assurance of care in surgical oncology

In an attempt to ensure high standards of cancer care, there is increasing interest in determining and monitoring the quality of interventions in surgical oncology. In recent years, this has been particularly the case for melanoma surgery. The vast majority of patients with melanoma undergo surgery. Usually, this is with combinations of wide excision, sentinel lymph node biopsy and lymphadenectomy. The indications for these procedures evolved during a time when no effective systemic adjuvant therapy was available, and whilst the rationale has been sound, the justification for differences in extent and thoroughness has generally been supported by inadequate or low-level evidence. This has led to a substantial variation among melanoma centres or even among surgeons within a centre in how these procedures are done. With recent rapid progress in the efficacy of systemic treatments that are impacting on overall survival, the prospect of long-term survival in these previously high risk patients means that more than ever long-term locoregional control of melanoma is imperative. Furthermore, the understanding of effects of systemic therapy on locoregional disease will only be interpretable if surgeons use standardized, high quality techniques. This article focuses on standardization and evolution of quality indicators for melanoma surgery and how these might have a positive impact on patient care.

Impact of Completion Lymph Node Dissection on Patients with Positive Sentinel Lymph Node Biopsy in Melanoma

BACKGROUND

Whether patients with positive SLNB should undergo complete lymph node dissection (CLND) is an important unanswered clinical question.

STUDY DESIGN

Patients diagnosed with positive SLNB at a melanoma referral center from 1991 to 2013 were studied. Outcomes of patients who underwent CLND were compared with those who did not undergo immediate CLND (observation [OBS] group).

RESULTS

There were 471 patients who had positive SLNB; 375 (79.6%) in the CLND group and 96 (20.4%) in the OBS group. The groups were similar except that the CLND group was younger and had more sentinel nodes removed. Five-year nodal recurrence-free survival was significantly better in the CLND group compared with the OBS group (93.1% vs 84.4%; p = 0.005). However, 5-year (66.4% vs 55.2%) and 10-year (59.5% vs 45.0%) distant metastasis-free survival rates were not significantly different (p = 0.061). The CLND group's melanoma-specific survival (MSS) rate was superior to that of the OBS group; 5-year MSS rates were 73.7% vs 65.5% and 10-year MSS rates were 66.8% vs 48.3% (p = 0.015). On multivariate analysis, CLND was associated with improved MSS (hazard ratio = 0.60; 95% CI, 0.40-0.89; p = 0.011) and lower nodal recurrence (hazard ratio = 0.46; 95% CI, 0.24-0.86; p = 0.016). Increased Breslow thickness, older age, ulceration, and trunk melanoma were all associated with worse outcomes. On subgroup analysis, the following factors were associated with better outcomes from CLND: male sex, nonulcerated primary, intermediate thickness, Clark level IV or lower extremity tumors.

CONCLUSIONS

Treatment of positive SLNB with CLND was associated with improved MSS and nodal recurrence rates. Follow-up beyond 5 years was needed to see a significant difference in MSS rates.

Evaluation of Melanoma Features and Their Relationship with Nodal Disease: The Importance of the Pathological Report

Background

The pathological features of melanoma biopsies can provide significant prognostic information that can help the surgeon evaluate the risk of nodal disease. The aim of this study was to attempt to determine the relationship between pathological features of primary melanoma and nodal disease, by sentinel node biopsy (SNB) and complete node dissection (CND).

Methods

A retrospective analysis was completed of patients who underwent SNB at AC Camargo Cancer Center, Sao Paulo, Brazil, between 2000 and 2010.

Results

A total of 697 patients were evaluated. By univariate analysis, it was found that histology, Clark level, Breslow depth, mitotic index, ulceration, regression, lymphatic and perineural invasion and satellitosis were significantly associated with SNB positivity. In the multivariate analysis, it was found that Breslow depth, mitotic index, ulceration, regression, lymphatic invasion and satellitosis were significant factors. In patients with a positive SNB, the primary tumor site, Clark level and Breslow depth greater than 2 mm were significantly related to non-sentinel node (NSN) positivity by univariate analysis. By multivariate analysis, Breslow depth greater than 2 mm was the only primary tumor feature that was significantly related (p = 0.038).

Conclusions

The indication of SNB should not be based solely on Breslow depth and ulceration or mitotic index. A complete evaluation of the pathological report should improve the identification of high-risk patients.

[Sentinel lymph node biopsy in melanoma: our experience over 8 years in a universitary hospital]

BACKGROUND

Since the introduction of sentinel lymph node biopsy, its use as a standard of care for patients with clinically node-negative cutaneous melanoma remains controversial. Our experience of sentinel lymph node biopsy for melanoma is presented and evaluated.

MATERIAL AND METHODS

A cohort study was conducted on 69 patients with a primary cutaneous melanoma and with no clinical evidence of metastasis, who had sentinel lymph node biopsy from October-2005 to December-2013. Sentinel lymph node biopsy was identified using preoperative lymphoscintigraphy and subsequent intraoperative detection with gamma probe.

RESULTS

The sentinel lymph node biopsy identification rate was 98.5%. The sentinel lymph node biopsy was positive for metastases in 23 patients (33.8%). Postoperative complications after sentinel lymph node biopsy were observed in 4.4% compared to 38% of complications in patients who had complete lymphadenectomy.

CONCLUSION

The sentinel lymph node biopsy in melanoma offers useful information about the lymphatic dissemination of melanoma and allows an approximation to the regional staging, sparing the secondary effects of lymphadenectomy. More studies with larger number of patients and long term follow-up will be necessary to confirm the validity of sentinel lymph node biopsy in melanoma patients, and especially of lymphadenectomy in patients with positive sentinel lymph node biopsy.

Lymph-Node Ratio in Patients with Cutaneous Melanoma: A Multi-Institution Prognostic Study

BACKGROUND

Lymph node ratio (LNR)-the number of metastatic lymph nodes (LNs) over the number of excised LNs after lymphadenectomy-is a prognostic factor for many solid tumors, but controversies still exist for skin melanoma. We investigated the prognostic relevance of LNR in melanoma patients and formulated a proposal for considering the LNR in the current American Joint Committee on Cancer (AJCC) N staging system.

METHODS

Retrospective data of 2,526 melanoma patients with LN metastasis from nine Italian institutions were collected in a multicenter database. The prognostic value of the LNR (categorized as A, ≤0.1; B, 0.11-0.25; and C, >0.25) was assessed by multivariable survival analysis.

RESULTS

LNR was a significant independent prognostic factor for melanoma-specific survival (LNR B vs. A: hazard ratio [HR] 1.47, 95 % CI 1.16-1.87, p = 0.002; LNR C vs. A: HR 1.84, 95 % CI 1.29-2.61, p = 0.001). The LNR had prognostic value in patients with AJCC N1a (one positive LN after sentinel LN biopsy [SLNB], HR 2.33, 95 % CI 1.49-3.63, p < 0.001) and N2a (two to three positive LNs after SLNB, HR 1.62, 95 % CI 1.09-2.40, p = 0.016) substages, but not in those with N1b (one clinically positive LN, p = 0.765), N2b (two to three clinically positive LNs, p = 0.165), and N3 (≥ four positive LNs, p = 0.084) substages.

CONCLUSION

The LNR is a prognostic factor in melanoma patients with one (AJCC N1a) and two to three (AJCC N2a) positive LNs after SLNB. This easy-to-obtain parameter should be considered for the staging of melanoma patients with LN metastasis, along with the number of positive LNs.

The optimum excision margin and regional node management for primary cutaneous T3 melanomas (2-4 mm in Thickness): a retrospective study of 1587 patients treated at a single center

OBJECTIVE

To determine the optimum excision margin and nodal management for patients with primary cutaneous melanomas 2.01- to 4.00-mm thick (T3 melanomas).

BACKGROUND

Currently available evidence does not reliably define the minimum safe excision margin and best nodal management for patients with primary cutaneous T3 melanomas.

METHODS

A retrospective study was conducted, analyzing data on 1587 patients with melanomas 2.01- to 4.00-mm thick treated at a single center.

RESULTS

A histopathologic excision margin of 8 mm or more (equivalent to a ≥1 cm surgical margin) was associated with increased local and in-transit recurrence-free survival [hazard ratio (HR) = 0.54; P = 0.008] and disease-free survival (DFS) (HR = 0.59; P = 0.001) compared with a less than 8-mm margin. The <8-mm group had reduced distant recurrence-free survival (DRFS) compared with the 8- to 16-mm group (HR = 1.63; P = 0.038). On multivariate analysis, patients with a positive sentinel lymph node (SLN) had significantly reduced melanoma-specific survival (MSS), DFS, regional node recurrence-free survival (RNRFS) and DRFS compared with patients with a negative SLN, unless an immediate completion lymph node dissection was performed. Patients in whom an SLN biopsy was not performed had significantly reduced MSS (HR = 2.10; P < 0.001), DFS (P < 0.001), RNRFS (P < 0.001), and DRFS (P = 0.010) compared with patients who received an SLN biopsy.

CONCLUSIONS

A histopathologic excision margin of 8 mm or more (corresponding to a ≥1 cm surgical excision margin) combined with SLN biopsy (followed by an immediate completion lymph node dissection if positive) provided T3 melanoma patients with optimum local, regional, and distant disease control and resulted in enhanced melanoma-specific survival.

The number of excised lymph nodes is associated with survival of melanoma patients with lymph node metastasis

BACKGROUND

Although the number of excised LNs has been associated with patient prognosis in many solid tumors, this association has not been widely investigated in cutaneous melanoma. This study aims to evaluate the association between the number of excised regional lymph nodes (LNs) and melanoma-specific survival.

PATIENT AND METHODS

Clinico-pathological data from 2507 patients with LN metastasis treated at nine Italian centers were retrospectively collected.

RESULTS

The number of excised LNs correlated with younger age (P < 0.001), male sex (P < 0.001), neck LN field (P < 0.001), LN micrometastasis (P < 0.001) and number of positive LNs (P < 0.001). The number of excised LNs was an independent prognostic factor (HR = 0.85; P = 0.002) after adjustment for other staging features. Upon subgroup analysis, the number of excised LNs had a significant prognostic value in patients bearing 1.01-2.00 mm (HR = 0.79; P = 0.032) and 2.01-4.00 mm (HR = 0.71; P < 0.001) thick melanomas, primary tumors showing ulceration (HR = 0.86; P = 0.033) and Clark level V of invasion (HR = 0.86; P = 0.010), LN micrometastasis (HR = 0.83; P = 0.014) and two to three positive LNs (HR = 0.71; P = 0.001). Finally, this study investigated the influence of the number of excised LNs on patient staging: only when ≥11 nodes were excised the AJCC N stage could stratify prognosis (P < 0.001). Considering the number of excised LNs for each lymphatic field, at least 14, 11, 10 and 12 LNs were needed to stage patients according to the AJCC N stage after a lymphadenectomy of the neck, axilla, inguinal and ilioinguinal LN fields, respectively.

CONCLUSIONS

The number of excised LNs can be considered for risk stratification of patients with regional LN metastasis from cutaneous melanoma. We demonstrated that a minimum number of LNs is required for the correct staging of patients. Further research is needed to evaluate the effectiveness of the minimum number of LNs to be dissected.

Outcome following sentinel node biopsy plus wide local excision versus wide local excision only for primary cutaneous melanoma: analysis of 5840 patients treated at a single institution

OBJECTIVE

Worldwide, sentinel node biopsy (SNB) is now a standard staging procedure for most patients with melanomas 1 mm or more in thickness, but its therapeutic benefit is not clear, pending randomized trial results. This study sought to assess the therapeutic benefit of SNB in a large, nonrandomized patient cohort.

METHODS

Patients with primary melanomas 1.00 mm or more thick or with adverse prognostic features treated with wide local excision (WLE) at a single institution between 1992 and 2008 were identified. The outcomes for those who underwent WLE plus SNB (n = 2909) were compared with the outcomes for patients in an observation (OBS) group who had WLE only (n = 2931). Median follow-up was 42 months.

RESULTS

Melanoma-specific survival (MSS) was not significantly different for patients in the SNB and OBS groups. However, a stratified univariate analysis of MSS for different thickness subgroups indicated a significantly better MSS for SNB patients with T2 and T3 melanomas (>1.0 to 4.0 mm thick) (P = 0.011), but this was not independently significant in multivariate analysis. Compared with OBS patients, SNB patients demonstrated improved disease-free survival (DFS) (P < 0.001) and regional recurrence-free survival (P < 0.001). There was also an improvement in distant metastasis-free survival (DMFS) for SNB patients with T2 and T3 melanomas (P = 0.041).

CONCLUSIONS

In this study, the outcome for the overall cohort after WLE alone did not differ significantly from the outcome after additional SNB. However, the outcome for the subgroup of patients with melanomas more than 1.0 to 4.0 mm in thickness was improved if they had a SNB, with significantly improved disease-free and DMFS.

Contemporary controversies and perspectives in the staging and treatment of patients with lymph node metastasis from melanoma, especially with regards positive sentinel lymph node biopsy

The management of melanoma lymph node metastasis particularly when detected by sentinel lymph node biopsy (SLNB) is still controversial. Results of the only randomized trial conducted to assess the therapeutic value of SLNB, the Multicenter Selective Lymphadenectomy Trial (MSLT-1), have not conclusively proven the effectiveness of this procedure but are interpreted by the authors and guidelines as indicating SLNB is standard of care. After surgery, interferon alpha had a small survival benefit and radiotherapy has limited effectiveness for patient at high-risk of regional recurrence. New drugs, including immune modulating agents and targeted therapies, already shown to be effective in patients with distant metastasis, are being evaluated in the adjuvant setting. In this regard, ensuring high quality of surgery through the identification of reliable quality assurance indicators and improving the homogeneity of prognostic stratification of patients entered onto clinical trials is paramount. Here, we review the controversial issues regarding the staging and treatment of melanoma patients with lymph node metastasis, present a summary of important and potentially practice changing ongoing research and provide a commentary on what it all means at this point in time.

Update and Review on the Surgical Management of Primary Cutaneous Melanoma

The surgical management of malignant melanoma historically called for wide excision of skin and subcutaneous tissue for any given lesion, but has evolved to be rationally-based on pathological staging. Breslow and Clark independently described level and thickness as determinant in prognosis and margin of excision. The American Joint Committee of Cancer (AJCC) in 1988 combined features from each of these histologic classifications, generating a new system, which is continuously updated and improved. The National Comprehensive Cancer Network (NCCN) has also combined several large randomized prospective trials to generate current guidelines for melanoma excision as well. In this article, we reviewed: (1) Breslow and Clark classifications, AJCC and NCCN guidelines, the World Health Organization's 1988 study, and the Intergroup Melanoma Surgical Trial; (2) Experimental use of Mohs surgery for in situ melanoma; and (3) Surgical margins and utility and indications for sentinel lymph node biopsy (SLNB) and lymphadenectomy. Current guidelines for the surgical management of a primary melanoma of the skin is based on Breslow microstaging and call for cutaneous margins of resection of 0.5 cm for MIS, 1.0 cm for melanomas ≤1.0 mm thick, 1-2 cm for melanoma thickness of 1.01-2 mm, 2 cm margins for melanoma thickness of 2.01-4 mm, and 2 cm margins for melanomas >4 mm thick. Although the role of SLNB, CLND, and TLND continue to be studied, current recommendations include SLNB for Stage IB (includes T1b lesions ≤1.0 with the adverse features of ulceration or ≥1 mitoses/mm²) and Stage II melanomas. CLND is recommended when sentinel nodes contain metastatic deposits.

Nonsentinel lymph node status in patients with cutaneous melanoma: results from a multi-institution prognostic study

PURPOSE

We investigated whether the nonsentinel lymph node (NSLN) status in patients with melanoma improves the prognostic accuracy of common staging features; then we formulated a proposal for including the NSLN status in the current melanoma staging system.

PATIENTS AND METHODS

We retrospectively collected the clinicopathologic data of 1,538 patients with positive SLN status who underwent completion lymph node dissection (CLND) at nine Italian centers. Multivariable Cox regression survival analysis was used to identify independent prognostic factors. Literature meta-analysis was used to summarize the available evidence on the prognostic value of the NSLN status in patients with positive SLN.

RESULTS

NSLN metastasis was observed in 353 patients (23%). After a median follow-up of 45 months, NSLN status was an independent prognostic factor for melanoma-specific survival (hazard ratio [HR] = 1.34; 95% CI, 1.18 to 1.52; P < .001). NSLN status efficiently stratified the prognosis of patients with two to three positive lymph nodes (n = 387; HR = 1.39; 95% CI, 1.07 to 1.81; P = .013), independently of other staging features. Searching the literature, this patient subgroup was investigated in other two studies. Pooling the results (n = 620 patients; 284 NSLN negative and 336 NSLN positive), we found that NSLN status is a highly significant prognostic factor (summary HR = 1.59; 95% CI, 1.27 to 1.98; P < .001) in patients with two to three positive lymph nodes.

CONCLUSION

These findings support the independent prognostic value of the NSLN status in patients with two to three positive lymph nodes, suggesting that this information should be considered for the routine staging in patients with melanoma.

The importance of adequate primary tumor excision margins and sentinel node biopsy in achieving optimal locoregional control for patients with thick primary melanomas

OBJECTIVE

This study sought to investigate the impact of histopathologically measured excision margins and SNB on local and locoregional disease control in patients with primary cutaneous melanomas more than 4 mm thick.

BACKGROUND

Most current guidelines recommend at least a 2-cm surgical margin (which corresponds to a 16-mm histopathologic margin). These guidelines are based on limited evidence, mostly obtained in patients who did not have an SNB.

METHODS

Histopathologic tumor excision margins for clinically lymph node-negative patients with melanomas more than 4 mm thick, treated at Melanoma Institute Australia (1992-2009), were determined. Clinicopathologic predictors of local and locoregional disease-free survival were investigated.

RESULTS

There were 632 patients eligible for the study; of these, 397 (62.8%) had an SNB. The median histopathologic excision margin was 15 mm (interquartile range, 11.0-19.5 mm). After a median follow-up of 37 months, local and locoregional recurrences were observed in 48 (7.6%) and 159 (25.2%) patients, respectively. Excision margin as a continuous variable was a significant predictor of local [hazard ratio (HR), 0.91; P < 0.001) and locoregional (HR, 0.97; P = 0.042) tumor control on multivariate analyses. Patients with histopathologic margins 16 mm or less had worse local disease-free survival (HR, 2.41; P = 0.01). Patients who did not have an SNB were at higher risk of locoregional recurrence (HR, 1.67; P = 0.003).

CONCLUSIONS

Histopathologically determined primary tumor excision margins more than 16 mm, corresponding to 2-cm surgical margins, were associated with better local control in patients with melanomas more than 4 mm thick. Patients achieved the best local and locoregional control when SNB was coupled with a more than 16-mm histologic excision margin.

SLN melanoma micrometastasis predictivity of nodal status: a long term retrospective study

Background

Completion lymph node dissection (CLND) is the gold standard treatment for patients with a positive sentinel lymph node (SLN) biopsy. Considering the morbidity associated with CLND it is important to identify histological features of the primary tumor and/or of SLN metastasis that could help to spare from CLND a subset of patients who have a very low risk of non-SLN metastasis. The objective of this study is to identify patients with a very low risk to develop non-SLNs recurrences and to limit unnecessary CLND.

Methods

A retrospective long-term study of 80 melanoma patients with positive SLN, undergone CLND, was assessed to define the risk of additional metastasis in the regional nodal basin, on the basis of intranodal distribution of metastatic cells, using the micro-morphometric analysis (Starz classification).

Results

This study demonstrates that among the demographic and pathologic features of primary melanoma and of SLN only the Starz classification shows prognostic significance for non-SLN status (p<0.0001). This parameter was also significantly associated with disease-free survival rate (p<0.0013).

Conclusion

The Starz classification can help to identify, among SLN positive patients, those who can have a real benefit from CLND. From the clinical point of view this easy and reliable method could lead to a significant reduction of unnecessary CLND in association with a substantial decrease in morbidity. The study results indicate that most of S1 subgroup patients might be safely spared from completion lymphatic node dissection. Furthermore, our experience demonstrated that Starz classification of SLN is a safe predictive index for patient stratification and treatment planning.

Interferon alpha for the adjuvant treatment of cutaneous melanoma

BACKGROUND

Interferon alpha is the only agent approved for the postoperative adjuvant treatment of high-risk cutaneous melanoma. However, the survival advantage associated with this treatment is unclear, especially in terms of overall survival. Thus, adjuvant interferon is not universally considered a gold standard treatment by all oncologists.

OBJECTIVES

To assess the disease-free survival and overall survival effects of interferon alpha as adjuvant treatment for people with high-risk cutaneous melanoma.

SEARCH METHODS

We searched the following databases up to August 2012: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2012, issue 8), MEDLINE (from 2005), EMBASE (from 2010), AMED (from 1985), and LILACS (from 1982). We also searched trials databases in 2011, and proceedings of the ASCO annual meeting from 2000 to 2011. We checked the reference lists of selected articles for further references to relevant trials.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) comparing interferon alpha to observation (or any other treatment) for the postoperative (adjuvant) treatment of patients with high-risk skin melanoma, that is, people with regional lymph node metastasis (American Joint Committee on Cancer (AJCC) TNM (tumour, lymph node, metastasis) stage III) undergoing radical lymph node dissection, or people without nodal disease but with primary tumour thickness greater than 1 mm (AJCC TNM stage II).

DATA COLLECTION AND ANALYSIS

Two authors extracted data, and a third author independently verified the extracted data. The main outcome measure was the hazard ratio (HR), which is the ratio of the risk of the event occurring in the treatment arm (adjuvant interferon) compared to the control arm (no adjuvant interferon). The survival data were either entered directly into Review Manager (RevMan) or extrapolated from Kaplan-Meier plots and then entered into RevMan. Based on the presence of between-study heterogeneity, we applied a fixed-effect or random-effects model for calculating the pooled estimates of treatment efficacy.

MAIN RESULTS

Eighteen RCTs enrolling a total of 10,499 participants were eligible for the review. The results from 17 of 18 of these RCTs, published between 1995 and 2011, were suitable for meta-analysis and allowed us to quantify the therapeutic efficacy of interferon in terms of disease-free survival (17 trials) and overall survival (15 trials). Adjuvant interferon was associated with significantly improved disease-free survival (HR (hazard ratio) = 0.83; 95% CI (confidence interval) 0.78 to 0.87, P value < 0.00001) and overall survival (HR = 0.91; 95% CI 0.85 to 0.97; P value = 0.003). We detected no significant between-study heterogeneity (disease-free survival: I² statistic = 16%, Q-test P value = 0.27; overall survival: I² statistic = 6%; Q-test P value = 0.38).Considering that the 5-year overall survival rate for TNM stage II-III cutaneous melanoma is 60%, the number needed to treat (NNT) is 35 participants (95% CI = 21 to 108 participants) in order to prevent 1 death. The results of subgroup analysis failed to answer the question of whether some treatment features (i.e. dosage, duration) might have an impact on interferon efficacy or whether some participant subgroups (i.e. with or without lymph node positivity) might benefit differently from interferon adjuvant treatment.Grade 3 and 4 toxicity was observed in a minority of participants: In some trials, no-one had fever or fatigue of Grade 3 severity, but in other trials, up to 8% had fever and up to 23% had fatigue of Grade 3 severity. Less than 1% of participants had fever and fatigue of Grade 4 severity. Although it impaired quality of life, toxicity disappeared after treatment discontinuation.

AUTHORS' CONCLUSIONS

The results of this meta-analysis support the therapeutic efficacy of adjuvant interferon alpha for the treatment of people with high-risk (AJCC TNM stage II-III) cutaneous melanoma in terms of both disease-free survival and, though to a lower extent, overall survival. Interferon is also valid as a reference treatment in RCTs investigating new therapeutic agents for the adjuvant treatment of this participant population. Further investigation is required to select people who are most likely to benefit from this treatment.

Is complete lymph node dissection after a positive sentinel lymph node biopsy for cutaneous melanoma always necessary? A meta-analysis

BACKGROUND

The current recommendation for patients with cutaneous melanoma and a positive sentinel lymph node (SLN) biopsy is a complete lymph node dissection (CLND). However, metastatic melanoma is not present in approximately 80% of CLND specimens. A meta-analysis was performed to identify the clinicopathological variables most predictive of non-sentinel node (NSN) metastases when the sentinel node is positive in patients with melanoma.

METHODS

A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google scholar, Science Direct, and Web of Science. The search identified 54 relevant articles reporting the frequency of NSN metastases in melanoma. Original data was abstracted from each study and used to calculate a pooled odds ratio (OR) and 95% confidence interval (95% CI).

FINDINGS

The pooled estimates that were found to be significantly associated with the high likelihood of NSN metastases were: ulceration (OR: 1.88, 95% CI: 1.53-2.31), satellitosis (OR: 3.25, 95% CI: 1.86-5.66), neurotropism (OR: 2.51, 95% CI: 1.39-4.53), >1 positive SLN (OR: 1.77, 95% CI: 1.2-2.62), Starz 3 (old) (OR: 1.83, 95% CI: 0.89-3.76), Angiolymphatic invasion (OR: 2.46, 95% CI: 1.34-4.54), extensive location (OR: 2.22, 95% CI: 1.74-2.81), macrometastases >2 mm (OR: 1.95, 95% CI: 1.61-2.35), extranodal extension (OR: 3.38, 95% CI: 1.79-6.40) and capsular involvement (OR: 3.16, 95% CI: 1.37-7.27). There were 3 characteristics not associated with NSN metastases: subcapsular location (OR: 0.51, 95% CI: 0.38-0.67), Rotterdam Criteria <0.1 mm (OR: 0.29, 95% CI: 0.17-0.50) and Starz I (new) (OR: 0.44, 95% CI: 0.22-0.91). Other variables including gender, Breslow thickness 2-4 mm and extremity as primary site were found to be equivocal.

INTERPRETATION

This meta-analysis provides evidence that patients with low SLN tumor burden could probably be spared the morbidity associated with CLND. We identified 9 factors predictive of non-SLN metastases that should be recorded and evaluated routinely in SLN databases. However, further studies are needed to confirm the standard criteria for not performing CLND.

Sentinel lymph node biopsy in melanoma: our 8-year clinical experience in a single French institute (2002-2009)

Background

Since the introduction of sentinel lymph node biopsy (SLNB), its use as a standard of care for patients with clinically node-negative cutaneous melanoma remains controversial. We wished to evaluate our experience of SLNB for melanoma.

Methods

A single center observational cohort of 203 melanoma patients with a primary cutaneous melanoma (tumour thickness > 1 mm) and without clinical evidence of metastasis was investigated from 2002 to 2009. Head and neck melanoma were excluded. SLN was identified following preoperative lymphoscintigraphy and intraoperative gamma probe interrogation.

Results

The SLN identification rate was 97%. The SLN was tumor positive in 44 patients (22%). Positive SLN was significantly associated with primary tumor thickness and microscopic ulceration. The median follow-up was 39.5 (5–97) months. Disease progression was significantly more frequent in SLN positive patients (32% vs 13%, p = 0.002). Five-year DFS and OS of the entire cohort were 79.6% and 84.6%, respectively, with a statistical significant difference between SLN positive (58.7% and 69.7%) and SLN negative (85% and 90.3%) patients (p = 0.0006 and p = 0.0096 respectively). Postoperative complications after SLNB were observed in 12% of patients.

Conclusion

Our data confirm previous studies and support the clinical usefulness of SLNB as a reliable and accurate staging method in patients with cutaneous melanoma. However, the benefit of additional CLND in patients with positive SLN remains to be demonstrated.

Surgeons' opinions on lymphadenectomy in melanoma patients with positive sentinel nodes: a worldwide web-based survey

PURPOSE

A worldwide web-based survey was conducted among melanoma surgeons to investigate opinions about completion lymph node dissection (CLND) in patients with positive sentinel nodes (SN).

METHODS

A questionnaire was designed following input from a group of melanoma surgeons. Cognitive interviews and pilot testing were performed. Surgeons identified through a systematic-review of the SN and CLND literature were invited by email.

RESULTS

Of 337 surgeons, 193 (57.2 %) from 25 countries responded (January-July 2011). Most respondents work in melanoma (30.1 %) and surgical oncology (44.6 %) units. In patients with a positive SN, 169 (91.8 %) recommend CLND; the strength of the recommendation is mostly influenced by patient comorbidities (64.7 %) and SN tumor burden (59.2 %). Seventy-one responders enroll patients in the second Multicenter Selective-Lymphadenectomy Trial (MSLT-2), and 64 of them (76 %) suggest entering the trial to majority of patients. In cases requiring neck CLND, level 1-5 dissection is recommended by 35 % of responders, whereas 62 % base the extent of dissection on primary site and lymphatic mapping patterns. Only inguinal dissection or ilioinguinal dissection is performed by 36 and 30 % of surgeons, respectively. The remaining 34 % select either procedure according to number of positive SNs, node of Cloquet status, and lymphatic drainage patterns. Most surgeons (81 %) perform full axillary dissections in positive SN cases.

CONCLUSIONS

The majority of melanoma surgeons recommend CLND in SN-positive patients. Surgeons participating in the MSLT-2 suggest entering the trial to the majority of patients. More evidence is needed to standardize the extent of neck and groin CLND surgeries.

Risk evaluation in cutaneous melanoma patients undergoing lymph node dissection: impact of POSSUM

INTRODUCTION

When lymphatic metastasis occurs, surgery is the primary treatment modality in melanoma patients. Depending on the tumour stage, patients receive a completion lymph node dissection (CLND) when a positive sentinel node is detected. Patients with clinically evident disease of the regional lymph nodes are recommended to undergo a therapeutic lymph node dissection (TLND). The aim of this study was to assess the morbidity of CLND and TLND and to evaluate the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) for preoperative risk adjustment of postoperative morbidity.

METHODS

The hospital files of 143 patients who underwent CLND and TLND for malignant melanoma were analysed. The POSSUM score was used to predict morbidity rates after surgery for the total patient group as well as separated for CLND and TLND patients.

RESULTS

The overall complication rate was 28.0% and the mortality rate was 0%. The morbidity rate predicted by POSSUM was 32.9%, the mortality 8.3%. Morbidity in patients undergoing CLND was significantly higher with regard to overall wound complications compared with patients with TLND. In these subgroups, POSSUM failed to predict the rates precisely.

CONCLUSIONS

The POSSUM score predicted the morbidity of the total patient group accurately but failed to predict the rates in the TLND and CLND subgroups. Patients receiving CLND showed the highest morbidity rates. Preoperative sentinel lymph node biopsy therefore has more influence on postoperative morbidity than the physiological parameters represented in the POSSUM physiological score.

Nuclear Medicine in Early-Stage Melanoma: Sentinel Node Biopsy-FDG-PET/CT

Sentinel node status is the most powerful prognostic factor in patients with early-stage melanoma. This review discusses several issues of clinical interest and technical points for an optimized sentinel node biopsy (SNB) procedure. The role of fluorodeoxyglucose positron emission tomography/computed tomography is clearly established in patients with suspicion of locoregional or distant recurrence of melanoma before any surgical decision. However, its role at initial staging or follow-up of patients with localized disease or with positive SNB is less clear. Further research and efforts should focus on identifying which groups of patients are at specific high risk of early distant recurrence.