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 surgical treatment of non-metastatic melanoma in a Clinical National Melanoma Registry Study Group (CNMR): a retrospective cohort quality improvement study to reduce the morbidity rates

Background

Reproducible, high-quality surgery is a key point in the management of cancer patients. Quality indicators for surgical treatment of melanoma has been presented with benchmarks but data on morbidity are still limited. This study presents the quality indicators on morbidity after surgical treatment for non-metastatic skin melanoma in an Italian registry.

Methods

Data were extracted from the Central National Melanoma Registry (CNMR) promoted by the Italian Melanoma Intergroup (IMI). All surgical procedures (WE, SNLB or LFND) for non-metastatic skin melanoma between January 2011 and February 2017 were evaluated for inclusion in the study. Only centers with adequate completeness of information (> 80%) were included in the study. Short-term complications (wound infection, dehiscence, skin graft failure and seroma) were investigated.

Results

Wound infection rate was 1.1% (0.4 to 2.7%) in WE, 1.3% (0.7 to 2.5%) in SLNB and 4.1% (2.1 to 8.0%) in LFND. Wound dehiscence rate was 2.0% (0.8 to 5.1%) in WE, 0.9% (0.2 to 3.0%) in SLNB and 2.8% (0.9 to 8.6%) in LFND. Seroma rate was 4.2% (1.5 to 11.1%) in SLNB and 15.1% (4.6 to 39.9%) in LFND. Unreliable information was found on skin graft failure.

Conclusions

Our findings contribute to available literature in setting up the recommended standards for melanoma centers, thus improving the quality of surgery offered to patients. A consensus on the core issues around surgical morbidity is needed to provide practical guidance on morbidity prevention and management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07705-4.

Assessing Tumor-Infiltrating Lymphocytes in Solid Tumors: A Practical Review for Pathologists and Proposal for a Standardized Method from the International Immuno-Oncology Biomarkers Working Group: Part 2: TILs in Melanoma, Gastrointestinal Tract Carcinomas, Non-Small Cell Lung Carcinoma and Mesothelioma, Endometrial and Ovarian Carcinomas, Squamous Cell Carcinoma of the Head and Neck, Genitourinary Carcinomas, and Primary Brain Tumors

Assessment of the immune response to tumors is growing in importance as the prognostic implications of this response are increasingly recognized, and as immunotherapies are evaluated and implemented in different tumor types. However, many different approaches can be used to assess and describe the immune response, which limits efforts at implementation as a routine clinical biomarker. In part 1 of this review, we have proposed a standardized methodology to assess tumor-infiltrating lymphocytes (TILs) in solid tumors, based on the International Immuno-Oncology Biomarkers Working Group guidelines for invasive breast carcinoma. In part 2 of this review, we discuss the available evidence for the prognostic and predictive value of TILs in common solid tumors, including carcinomas of the lung, gastrointestinal tract, genitourinary system, gynecologic system, and head and neck, as well as primary brain tumors, mesothelioma and melanoma. The particularities and different emphases in TIL assessment in different tumor types are discussed. The standardized methodology we propose can be adapted to different tumor types and may be used as a standard against which other approaches can be compared. Standardization of TIL assessment will help clinicians, researchers and pathologists to conclusively evaluate the utility of this simple biomarker in the current era of immunotherapy.

Enhanced chemosensitization of anoikis-resistant melanoma cells through syndecan-2 upregulation upon anchorage independency

Syndecan family proteins are heparan sulfate proteoglycans, which involved in various cellular activities and associating with metastatic potential and chemosensitivity of tumor cells. Melanoma is one of malignant tumors with poor prognosis upon metastasis. Previously, we had shown that melanoma cells remained survived under cell detachment, which was similar to the initial steps of tumor metastasis. Downregulation of syndecan-1 and upregulation of syndecan-2 in melanoma A375 cells were observed by different suspension conditions. Specific gene alterations also increased melanoma malignancy under anchorage independency. Thus, we would like to investigate in further the role of specific gene alteration, so that it could be used to develop novel strategy to treat melanoma.

In this paper, we found that syndecan-2 expression level as well the kinase phosphorylation levels increased upon anchorage independency. The pathway to regulate syndecan-2 expression shifted from PKCα/β-dependent under adhesion into PKCδ-dependent under cell suspension. Manipulation of syndecan-2 expression showed that PI3K and ERK phosphorylation as well the migratory ability increased with increased syndecan-2 expression level. In addition, suspended melanoma cells were more sensitive to chemoagents, which correlated with syndecan-2 overexpression, PI3K and ERK activations, serum level, and the presence of glycosaminoglycans.

In conclusion, we showed upregulation of syndecan-2 in anoikis-resistant melanoma cells enhanced chemosensitivity through PI3K and ERK activation. This observation would support and refine the strategy of adjuvant chemotherapy to overcome metastatic melanoma.

Genetic progression of malignant melanoma

Malignant melanoma of the skin is the most aggressive human cancer given that a primary tumor a few millimeters in diameter frequently has full metastatic competence. In view of that, revealing the genetic background of this potential may also help to better understand tumor dissemination in general. Genomic analyses have established the molecular classification of melanoma based on the most frequent driver oncogenic mutations (BRAF, NRAS, KIT) and have also revealed a long list of rare events, including mutations and amplifications as well as genetic microheterogeneity. At the moment, it is unclear whether any of these rare events have role in the metastasis initiation process since the major drivers do not have such a role. During lymphatic and hematogenous dissemination, the clonal selection process is evidently reflected by differences in oncogenic drivers in the metastases versus the primary tumor. Clonal selection is also evident during lymphatic progression, though the genetic background of this immunoselection is less clear. Genomic analyses of metastases identified further genetic alterations, some of which may correspond to metastasis maintenance genes. The natural genetic progression of melanoma can be modified by targeted (BRAF or MEK inhibitor) or immunotherapies. Some of the rare events in primary tumors may result in primary resistance, while further new genetic lesions develop during the acquired resistance to both targeted and immunotherapies. Only a few genetic lesions of the primary tumor are constant during natural or therapy-modulated progression. EGFR4 and NMDAR2 mutations, MITF and MET amplifications and PTEN loss can be considered as metastasis drivers. Furthermore, BRAF and MITF amplifications as well as PTEN loss are also responsible for resistance to targeted therapies, whereas NRAS mutation is the only founder genetic lesion showing any association with sensitivity to immunotherapies. Unfortunately, there are hardly any data on the possible organ-specific metastatic drivers in melanoma. These observations suggest that clinical management of melanoma patients must rely on the genetic analysis of the metastatic lesions to be able to monitor progression-associated changes and to personalize therapies.

Association of sentinel lymph node diameter with melanoma metastasis

BACKGROUND

Lymph nodes are an important part of the immune system and the size of the lymph node reflects local immunologic activity. The purpose of this study was to examine the association between sentinel lymph node (SLN) size and the presence of nodal metastasis in patients with melanoma.

METHODS

Retrospective review of a prospectively maintained database of patients undergoing SLN biopsy for cutaneous melanoma between February 1995 and January 2013. The maximum pathologic diameter and the volume of the largest node was used. A nodal diameter of 1.5 cm, included in 2 interquartile ranges of both positive and negative SLNs, was used as the cutoff for multivariate regression.

RESULTS

Of 1,017 SLN biopsies, 826 (81%) had complete size measurements and were included in the analysis. Patients with a positive SLN were younger (median 50 vs 53 years, P = .032), had deeper primary lesions (2 vs 1.4 mm, P < .001), and had larger SLN volume (.8 vs .6 cc, P = .009) or maximum diameter (1.9 vs. 1.6 cm, P = .03). Sex, pathologic ulceration, mitosis, and the type or location of the primary was not statistically different. On multivariate analysis; age, depth of primary, and both SLN volume and maximum diameter remained significant. An SLN greater than 1.5 cm in maximum diameter has a 60% increased odds ratio of being positive after adjusting for age, sex, and depth of primary lesion (P = .046).

CONCLUSIONS

Larger SLN maximum diameter is associated with nodal positivity independent of age, sex, depth of primary lesion, and location of SLN biopsy. The etiology and significance of larger SLNs warrant further analysis.

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.

Videoscopic ilioinguinal lymphadenectomy for groin lymph node metastases from melanoma

BACKGROUND

Groin lymph node dissection for melanoma is burdened by high postoperative morbidity. Videoscopic lymphadenectomy may lower the incidence of complications, including infection, dehiscence and lymphoedema. This pilot study aimed to investigate the feasibility and postoperative outcomes of videoscopic ilioinguinal lymphadenectomy in patients with inguinal nodal melanoma metastases.

METHODS

Patients with inguinal nodal metastases, with either a positive sentinel lymph node biopsy or clinically positive nodes from melanoma, were enrolled. Inguinal dissection was performed via three ports. Iliac dissection was obtained through a preperitoneal access. Intraoperative and postoperative data were collected.

RESULTS

Of 23 patients selected for 24 procedures, four needed conversion to an open procedure. Median duration of surgery was 270 (i.q.r. 245-300) min. Wound-related postoperative complications occurred in four patients, although only one needed further intervention. The median number of excised lymph nodes was 21 (i.q.r. 15-25). After a median follow-up of 18 months, regional lymph node recurrence was observed in two patients.

CONCLUSION

Videoscopic ilioinguinal lymphadenectomy for melanoma groin lymph node metastases is technically feasible, safe, and associated with acceptable morbidity and oncological outcome.

Estrogen Receptor β Agonists Differentially Affect the Growth of Human Melanoma Cell Lines

Background

Cutaneous melanoma is an aggressive malignancy; its incidence is increasing worldwide and its prognosis remains poor. Clinical observations indicate that estrogen receptor β (ERβ) is expressed in melanoma tissues and its expression decreases with tumor progression, suggesting its tumor suppressive function. These experiments were performed to investigate the effects of ERβ activation on melanoma cell growth.

Methods and Results

Protein expression was analyzed by Western blot and immunofluorescence assays. Cell proliferation was assessed by counting the cells by hemocytometer. ERβ transcriptional activity was evaluated by gene reporter assay. Global DNA methylation was analyzed by restriction enzyme assay and ERβ isoforms were identified by qRT-PCR. We demonstrated that ERβ is expressed in a panel of human melanoma cell lines (BLM, WM115, A375, WM1552). In BLM (NRAS-mutant) cells, ERβ agonists significantly and specifically inhibited cell proliferation. ERβ activation triggered its cytoplasmic-to-nuclear translocation and transcriptional activity. Moreover, the antiproliferative activity of ERβ agonists was associated with an altered expression of G1-S transition-related proteins. In these cells, global DNA was found to be hypomethylated when compared to normal melanocytes; this DNA hypomethylation status was reverted by ERβ activation. ERβ agonists also decreased the proliferation of WM115 (BRAF V600D-mutant) cells, while they failed to reduce the growth of A375 and WM1552 (BRAF V600E-mutant) cells. Finally, we could observe that ERβ isoforms are expressed at different levels in the various cell lines. Specific oncogenic mutations or differential expression of receptor isoforms might be responsible for the different responses of cell lines to ERβ agonists.

Conclusions

Our results demonstrate that ERβ is expressed in melanoma cell lines and that ERβ agonists differentially regulate the proliferation of these cells. These data confirm the notion that melanoma is a heterogeneous tumor and that genetic profiling is mandatory for the development of effective personalized therapeutic approaches for melanoma patients.

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.