A multicentre study of naevus-associated melanoma vs. de novo melanoma, tumour thickness and body site differences.

BACKGROUND: Whether melanoma in histological contiguity with a naevus [naevus-associated melanoma (NAM)] is distinctly different from melanoma arising de novo remains unclear. OBJECTIVES: To determine whether the characteristics of de novo melanoma differ from NAM and are not due to naevus obliteration in thicker tumours. METHODS: We conducted a multicentre retrospective study of de novo melanoma and NAM in seven referral centres in Europe, Australia and the USA between 2006 and 2015. RESULTS: In a total of 9474 localized melanomas, de novo melanoma was associated with thicker tumours and body site differences compared with NAM. In the subset of T1 melanomas (n = 5307), similar body site differences were found in multivariate analysis by body site. When compared with NAM, de novo melanoma was more likely to affect older individuals (≥ 70 years) when located on the head/neck [odds ratio (OR) 4·65, 95% confidence interval (CI) 2·55-8·46], the trunk (OR 1·82, 95% CI 1·40-2·36) or the upper extremity (OR 1·69, 95% CI 1·14-2·50), was more likely to affect female patients when located on the lower extremities (OR 1·36, 95% CI 1·03-1·80), and was more likely to be of the nodular melanoma subtype (OR 2·23, 95% CI 1·14-4·35) when located on the trunk. De novo melanoma was less likely to have regression present compared with NAM. CONCLUSIONS: Clinicopathological and body site differences between de novo melanoma and NAM support the divergent pathway model of development. These differences were also found in thin melanomas, suggesting that de novo melanomas are different from NAM and their differences are not due to the obliteration of naevus remnants in thicker tumours.

Histopathological features of complete pathological response predict recurrence-free survival following neoadjuvant targeted therapy for metastatic melanoma.

BACKGROUND: Recent clinical trials demonstrated the safety and efficacy of neoadjuvant dabrafenib and trametinib (DT) among patients with surgically resectable clinical stage III BRAFV600E/K mutant melanoma. Although patients achieving a complete pathological response (pCR) exhibited superior recurrence-free survival (RFS) versus those who did not, 30% of pCR patients relapsed. We sought to identify whether histopathological features of the pathological response further delineated risk of relapse. METHODS: Surgical resection specimens from DT-treated patients in two phase 2 clinical trials were reviewed. Histopathological features, including relative amounts of viable tumour, necrosis, melanosis, and fibrosis (hyalinized or immature/proliferative) were assessed for associations with patient outcomes. RESULTS: Fifty-nine patients underwent surgical resection following neoadjuvant DT. Patients achieving pCR (49%) had longer RFS compared with patients who did not (P = 0.005). Patients whose treated tumour showed any hyalinized fibrosis had longer RFS versus those without (P = 0.014), whereas necrosis (P = 0.012) and/or immature/proliferative fibrosis (P = 0.026) correlated with shorter RFS. Multivariable analyses showed absence of pCR or presence of immature fibrosis independently predicted shorter RFS. Among pCR patients, mature/hyalinized-type fibrosis correlated with improved RFS (P = 0.035). CONCLUSIONS: The extent and composition of the pathological response following neoadjuvant DT in BRAFV600E/K mutant melanoma correlates with RFS, including pCR patients. These findings support the need for detailed histological analysis of specimens collected after neoadjuvant therapy.

Pathological assessment of resection specimens after neoadjuvant therapy for metastatic melanoma.

Background: Clinical trials have recently evaluated safety and efficacy of neoadjuvant therapy among patients with surgically resectable regional melanoma metastases. To capture informative prognostic data connected to pathological response in such trials, it is critical to standardize pathologic assessment and reporting of tumor response after this treatment. Methods: The International Neoadjuvant Melanoma Consortium meetings in 2016 and 2017 assembled pathologists from academic centers to develop consensus guidelines for pathologic examination and reporting of surgical specimens from AJCC (8th edition) stage IIIB/C/D or oligometastatic stage IV melanoma patients treated with neoadjuvant-targeted or immune therapy. Patterns of pathologic response are provided context to inform these guidelines. Results: Based on our collective experience and guided by efforts in well-established neoadjuvant settings like breast cancer, procedures directing handling of pre- and post-neoadjuvant therapy-treated melanoma specimens are provided to facilitate comparison of findings across different trials and centers. Definitions of pathologic response are provided together with guidelines for reporting and quantifying the extent of pathologic response. Finally, the spectrum of histopathologic responses observed following neoadjuvant-targeted and immune-checkpoint therapy is described and illustrated. Conclusions: Standardizing pathologic evaluation of resected melanoma metastases following neoadjuvant-targeted or immune-checkpoint therapy allows more robust stratification of patient outcomes. This includes recognizing the spectrum of histopathologic response patterns to neoadjuvant therapy and a standard approach to grading pathologic responses. Such an approach will facilitate comparison of results across clinical trials and inform ongoing correlative studies into the mechanisms of response and resistance to agents applied in the neoadjuvant setting.

Is surviving enough? Coping and impact on activities of daily living among melanoma patients with lymphoedema.

We assessed the impact of lymphoedema (defined as ≥ 10% limb volume change) on quality of life (QOL), ability to perform activities of daily living (ADLs) and coping in 277 melanoma patients. Limb volume was measured prospectively, pre-operatively and every 3-6 months for 18 months post-operatively using a perometer. Three questionnaires were administered to measure QOL, coping and impact on ADLs. Statistical analyses were conducted using longitudinal logistic regression models. At 18 months, the cumulative incidence of lymphoedema was 31% in patients with upper extremity nodal basin treatment and 40% in lower extremity nodal basin treatment patients. Patients with lower extremity lymphoedema reported lower QOL scores than those with upper extremity lymphoedema. Over 18 months, both groups with mild and moderate lymphoedema showed improvement in coping [odds ratio (OR): 6.67, 95% confidence interval (CI): 3.30-13.47] and performance of ADLs (OR: 7.46, CI: 3.38-16.47). Over the course of 18 months, men were found to have poorer coping scores than women (OR: 2.91, CI: 1.35-6.27). Lymphoedema was associated with improvement in coping over time (P = 0.08) and a higher reported interference with ADLs (OR: 2.53, CI: 1.29-4.97). Patient education about lymphoedema at the time of surgical consent may improve self-efficacy and coping ability. Effective management of lymphoedema may improve patient QOL and reduce interference with ADLs.

Multimethod imaging, staging, and spectrum of manifestations of metastatic melanoma.

The incidence of melanoma has been steadily increasing. Imaging plays an important role in tumour assessment as metastatic melanoma can involve multiple organs. Computed tomography (CT) is currently the most widely used technique for tumour staging, surveillance and assessment of therapeutic response, but ultrasound, magnetic resonance imaging (MRI) and positron-emission tomography (PET)-CT also play important roles in the imaging of this tumour. In this article, we review the pathways of spread, staging according to the recently updated TNM classification, pathology, typical and atypical imaging features at common and uncommon sites, and treatment of metastatic melanoma.

A novel AKT3 mutation in melanoma tumours and cell lines.

Recently, a rare activating mutation of AKT1 (E17K) has been reported in breast, ovarian, and colorectal cancers. However, analogous activating mutations in AKT2 or AKT3 have not been identified in any cancer lineage. To determine the prevalence of AKT E17K mutations in melanoma, the most aggressive form of skin cancer, we analysed 137 human melanoma specimens and 65 human melanoma cell lines for the previously described activating mutation of AKT1, and for analogous mutations in AKT2 and AKT3. We identified a single AKT1 E17K mutation. Remarkably, a previously unidentified AKT3 E17K mutation was detected in two melanomas (from one patient) as well as two cell lines. The AKT3 E17K mutation results in activation of AKT when expressed in human melanoma cells. This represents the first report of AKT mutations in melanoma, and the initial identification of an AKT3 mutation in any human cancer lineage. We have also identified the first known human cell lines with naturally occurring AKT E17K mutations.

Phase II trial of imatinib mesylate in patients with metastatic melanoma.

Metastatic melanoma cells express a number of protein tyrosine kinases (PTKs) that are considered to be targets for imatinib. We conducted a phase II trial of imatinib in patients with metastatic melanoma expressing at least one of these PTKs. Twenty-one patients whose tumours expressed at least one PTK (c-kit, platelet-derived growth factor receptors, c-abl, or abl-related gene) were treated with 400 mg of imatinib twice daily. One patient with metastatic acral lentiginous melanoma, containing the highest c-kit expression among all patients, had dramatic improvement on positron emission tomographic scan at 6 weeks and had a partial response lasting 12.8 months. The responder had a substantial increase in tumour and endothelial cell apoptosis at 2 weeks of treatment. Imatinib was fairly well tolerated: no patient required treatment discontinuation because of toxicity. Fatigue and oedema were the only grade 3 or 4 toxicities that occurred in more than 10% of the patients. Imatinib at the studied dose had minimal clinical efficacy as a single-agent therapy for metastatic melanoma. However, based on the characteristics of the responding tumour in our study, clinical activity of imatinib, specifically in patients with melanoma with certain c-kit aberrations, should be examined.

Epidermal hyperplasia overlying human melanoma correlates with tumour depth and angiogenesis.

The aim of this study was to determine whether epidermal hyperplasia overlying cutaneous human melanoma is associated with increased tumour angiogenesis, tumour growth and the potential for metastasis. Forty-two surgical specimens of cutaneous human melanoma of different depths, each containing epidermis present in the tumour-free margin, were analysed by immunohistochemistry for the expression of the pro-angiogenic molecules basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) and the anti-angiogenic molecule interferon-beta (IFN-beta). The epidermis overlying intermediate and thick (1.0-10.0 mm), but not thin (0.5-1.0 mm), melanoma specimens was hyperplastic. Although the expression level of bFGF, VEGF and IL-8 in the epidermis directly overlying the tumour was similar to that in the distant epidermis, the expression of IFN-beta was significantly decreased in keratinocytes overlying intermediate and thick, but not thin, melanomas. The microvessel density was also increased in intermediate and thick specimens. Human melanoma cells were injected subcutaneously into nude mice. The resulting tumours were used to determine the association between overlying epidermal hyperplasia and neoplastic angiogenesis. Similar to human autochthonous melanomas, epidermal hyperplasia was found only over lesions produced by metastatic cells. Although there was no change in the expression of the pro-angiogenic molecules, the expression of IFN-beta was significantly decreased in the hyperplastic epidermis. Conditioned medium collected from cultures of the metastatic cell line induced in vitro proliferation of mouse keratinocytes, whereas conditioned medium collected from cultures of the non-metastatic cell line did not. Collectively, the data demonstrate that metastatic melanoma cells induce keratinocyte proliferation, leading to decreased expression of the negative regulator of angiogenesis, IFN-beta, and hence to increased angiogenesis.

[Effects of vascular endothelial growth factor D on the signaling cascade of sentinel lymphatic endothelial cells from melanoma patients undergoing sentinel lymphadenectomy].

Advances in surgical treatment, including sentinel lymphadenectomy, permit the pathologic staging of regional lymph nodes most likely to contain metastasis by identifying afferent lymphatic channels, which specifically drain the primary tumor site. Recently, a new member of the angiogenic molecule in VEGF family, VEGF-D, has been identified that induces lymphangiogenesis via high-affinity binding to VEGFR-3. VEGF-D is predominantly expressed in lymphatic endothelium. We have previously developed a novel method for the isolation of anatomically-defined lymphatic endothelial cells (LECs) from human sentinel lymphatic channel during SLN biopsy. The effect of VEGF-D on the extracellular signal-regulated kinases (Erk)-1/2 and Akt signaling pathway was examined by Western blot analysis. VEGF-D (500 ng/ml) apparently upregulated phospho-p44/phospho-p42 activity in human isolated LECs by Western blot analysis, while phospho-Akt activity was not at all changed by VEGF-D exposure without the change of total p44/p42 and Akt expression. U0126 (20 microM), the MEK1/2 inhibitor, could completely block the VEGF-D induced phospholylation of Erk1/2 signaling pathway. These data demonstrate that VEGF-D induces p44/p42 in human LECs and suggests that this signaling pathway activation may be important in LEC biology and lymphoangiogenesis, which may lead to the progression of new strategies of cancer treatment.

Patterns of regional and distant metastasis in patients with conjunctival melanoma: experience at a cancer center over four decades.

OBJECTIVE: The regional lymph nodes generally are believed to be the most common first site of metastasis for conjunctival malignant melanoma, but the pattern of nodal metastasis in this disease has not been well established. The goal of this study was to determine the frequency, location, and timing of regional lymph node metastasis in patients with conjunctival melanoma treated at one cancer center over four decades. DESIGN: Retrospective case series. PARTICIPANTS: Twenty-seven patients. METHODS: The clinical records of 27 patients with conjunctival malignant melanoma were reviewed retrospectively. MAIN OUTCOME MEASURES: The rates of local conjunctival recurrence, regional nodal metastasis, and distant metastasis were analyzed along with overall survival. The follow-up time ranged from 2.5 to 17 years (median, 6 years). RESULTS: Eleven patients (41%) experienced clinical regional lymph node metastasis 1.5 to 6.0 years (mean, 3.2 years) after the initial diagnosis. The involved lymphatics were the preauricular (parotid) nodes in 8 patients (73%), the submandibular nodes in 1 patient (9%), and the deeper cervical nodes in 2 patients (18%). In seven patients (26%), distant metastasis developed without evidence of prior or concurrent regional nodal disease. Patients in whom distant metastasis developed without clinical evidence of regional nodal involvement were more likely to have had local conjunctival recurrence (P = 0.03) and a higher number of local recurrences (P = 0.05) compared with patients with regional lymph nodes as the site of first metastasis. The 5- and 10-year overall survival rates were 74% and 41%, respectively. CONCLUSIONS: Regional lymph node metastasis occurred in a higher percentage of patients with conjunctival malignant melanoma than has been reported previously. Preauricular lymph nodes were most commonly involved. Distant metastasis without prior or concurrent lymph node involvement was not a rare event.

Melanoma.

The presentations at the American Society of Clinical Oncology 2001 meeting reported or updated the results of phase I, II, and III randomized trials and also reported important meta-analyses and retrospective studies impacting on the management of patients with melanoma. In the treatment of early stage melanoma, the prognostic significance of pathologic status of sentinel lymph nodes was affirmed. With respect to regional nodal involvement (American Joint Committee on Cancer [AJCC] stage III), investigators presented the interim results of the United Kingdom randomized low-dose interferon (IFN) trial, and up-to-date meta-analyses of several IFN trials including a pooled analysis of the Eastern Cooperative Oncology Group trials evaluating interferon in the adjuvant setting. In the advanced disease setting (AJCC stage IV), several studies elucidated the pros and cons of biochemotherapy in patients with metastatic melanoma, with an emphasis on seeking to improve response in the central nervous system and durability of response in general. Thought provoking was new data regarding the potential for lovastatin to act as a chemopreventive agent for melanoma. Translational studies were presented, one supporting the importance of HLA-typing in developing targeted vaccine therapy. Finally, the results of a novel experimental melanoma vaccine were presented using autologous tumor-derived heat-shock protein peptide complex-96 (HSPPC-96).

Prognostic factors analysis of 17,600 melanoma patients: validation of the American Joint Committee on Cancer melanoma staging system.

PURPOSE: The American Joint Committee on Cancer (AJCC) recently proposed major revisions of the tumor-node-metastases (TNM) categories and stage groupings for cutaneous melanoma. Thirteen cancer centers and cancer cooperative groups contributed staging and survival data from a total of 30,450 melanoma patients from their databases in order to validate this staging proposal. PATIENTS AND METHODS: There were 17,600 melanoma patients with complete clinical, pathologic, and follow-up information. Factors predicting melanoma-specific survival rates were analyzed using the Cox proportional hazards regression model. Follow-up survival data for 5 years or longer were available for 73% of the patients. RESULTS: This analysis demonstrated that (1) in the T category, tumor thickness and ulceration were the most powerful predictors of survival, and the level of invasion had a significant impact only within the subgroup of thin (< or = 1 mm) melanomas; (2) in the N category, the following three independent factors were identified: the number of metastatic nodes, whether nodal metastases were clinically occult or clinically apparent, and the presence or absence of primary tumor ulceration; and (3) in the M category, nonvisceral metastases was associated with a better survival compared with visceral metastases. A marked diversity in the natural history of pathologic stage III melanoma was demonstrated by five-fold differences in 5-year survival rates for defined subgroups. This analysis also demonstrated that large and complex data sets could be used effectively to examine prognosis and survival outcome in melanoma patients. CONCLUSION: The results of this evidence-based methodology were incorporated into the AJCC melanoma staging as described in the companion publication.

Final version of the American Joint Committee on Cancer staging system for cutaneous melanoma.

PURPOSE: To revise the staging system for cutaneous melanoma under the auspices of the American Joint Committee on Cancer (AJCC). MATERIALS AND METHODS: The prognostic factors analysis described in the companion publication (this issue), as well as evidence from the published literature, was used to assemble the tumor-node-metastasis criteria and stage grouping for the melanoma staging system. RESULTS: Major changes include (1) melanoma thickness and ulceration but not level of invasion to be used in the T category (except for T1 melanomas); (2) the number of metastatic lymph nodes rather than their gross dimensions and the delineation of clinically occult (ie, microscopic) versus clinically apparent (ie, macroscopic) nodal metastases to be used in the N category; (3) the site of distant metastases and the presence of elevated serum lactic dehydrogenase to be used in the M category; (4) an upstaging of all patients with stage I, II, and III disease when a primary melanoma is ulcerated; (5) a merging of satellite metastases around a primary melanoma and in-transit metastases into a single staging entity that is grouped into stage III disease; and (6) a new convention for defining clinical and pathologic staging so as to take into account the staging information gained from intraoperative lymphatic mapping and sentinel node biopsy. CONCLUSION: This revision will become official with publication of the sixth edition of the AJCC Cancer Staging Manual in the year 2002.

Sentinel lymph node biopsy for melanoma: controversy despite widespread agreement.

Although sentinel lymph node (SLN) biopsy for melanoma has been adopted throughout the United States and abroad as a standard method of determining the pathologic status of the regional lymph nodes, some controversy still exists regarding the validity and utility of this procedure. SLN biopsy is a minimally invasive procedure, performed on an outpatient basis at the time of wide local excision of the melanoma, with little morbidity. Numerous studies have documented the accuracy of this procedure for identifying nodal metastases. There are four major reasons to perform SLN biopsy. First, SLN biopsy improves the accuracy of staging and provides valuable prognostic information for patients and physicians to guide subsequent treatment decisions. Second, SLN biopsy facilitates early therapeutic lymph node dissection for those patients with nodal metastases. Third, SLN biopsy identifies patients who are candidates for adjuvant therapy with interferon alfa-2b. Fourth, SLN biopsy identifies homogeneous patient populations for entry onto clinical trials of novel adjuvant therapy agents. Overall, the benefit of accurate nodal staging obtained by SLN biopsy far outweighs the risks and has important implications for patient management.

Dominant-negative transcription factor AP-2 augments SB-2 melanoma tumor growth in vivo.

We have previously demonstrated that the transition of melanoma to the metastatic phenotype is associated with a loss of expression of the transcription factor AP-2. To further investigate the role of AP-2 in the progression of human melanoma, we attempted to inactivate AP-2 in primary cutaneous SB-2 melanoma cells by using a dominant-negative AP-2, or AP-2B, gene. AP-2B is an alternatively spliced AP-2 variant capable of inhibiting AP-2 trans-activator function. Stable transfection of primary cutaneous melanoma SB-2 cells with the dominant-negative AP-2B gene was confirmed by RT--PCR and Northern blot analyses. Electromobility shift assay using nuclear extracts from these cell lines demonstrated decreased functional binding of AP-2B-transfected cells to the AP-2 consensus binding sequence compared with neo-transfected controls. In addition, CAT activity driven by a construct containing the AP-2 consensus binding sequence was downregulated in the AP-2B transfected cells, indicating AP-2 activity was quenched in the transfected cells. Orthotopic (subcutaneous) injection of the dominant-negative (AP-2B)-transfected cell lines into nude mice increased their tumorigenicity compared to control neo-transfected cells. The AP-2B-transfected cells displayed an increase in MMP-2 expression (by Northern blot) and MMP-2 activity (by zymography), which resulted in an increase in invasiveness through Matrigel-coated filters. The AP-2B-transfected tumors also displayed an increase in MMP-2 expression, microvessel density, and angiogenesis in vivo. These results demonstrate that inactivation of AP-2 contributes to the progression of melanoma, at least partially via deregulation of the MMP-2 gene.

Sentinel lymph node biopsy for melanoma: how many radioactive nodes should be removed?

BACKGROUND: Sentinel lymph node (SLN) biopsy has become a standard method of staging patients with cutaneous melanoma. Sentinel lymph node biopsy usually is performed by intradermal injection of a vital blue dye (isosulfan blue) plus radioactive colloid (technetium sulfur colloid) around the site of the tumor. Intraoperative gamma probe detection has been shown to improve the rate of SLN identification compared to the use of blue dye alone. However, multiple sentinel nodes often are detected using the gamma probe. It is not clear whether these additional lymph nodes represent true sentinel nodes, or second-echelon lymph nodes that have received radiocolloid particles that have passed through the true sentinel node. This analysis was performed to determine the frequency with which these less radioactive lymph nodes contain metastatic disease when the most radioactive, or "hottest," node does not. MATERIALS AND METHODS: In the Sunbelt Melanoma Trial, 1184 patients with cutaneous melanoma of Breslow thickness 1.0 mm or more had sentinel lymph nodes identified. Sentinel lymph node biopsy was performed by injection of technetium sulfur colloid plus isosulfan blue dye in 99% of cases. Intraoperative determination of the degree of radioactivity of sentinel nodes (ex vivo) was measured, as well as the degree of blue dye staining. RESULTS: Sentinel nodes were identified in 1373 nodal basins in 1184 patients. A total of 288 of 1184 patients (24.3%) were found to have sentinel node metastases detected by histology or immunohistochemistry. Nodal metastases were detected in 306 nodal basins in these 288 patients. There were 175 nodal basins from 170 patients in which at least one positive sentinel node was found and more than one sentinel node was harvested. Blue dye staining was found in 86.3% of the histologically positive sentinel nodes and 66.4% of the negative sentinel nodes. In 40 of 306 positive nodal basins (13.1%), the most radioactive sentinel node was negative for tumor when another, less radioactive, sentinel node was positive for tumor. In 20 of 40 cases (50%), the less radioactive positive sentinel node contained 50% or less of the radioactive count of the hottest lymph node. The cervical lymph node basin was associated with an increased likelihood of finding a positive sentinel node other than the hottest node. CONCLUSIONS: If only the most radioactive sentinel node in each basin had been removed, 13.1% of the nodal basins with positive sentinel nodes would have been missed. It is recommended that all blue lymph nodes and all nodes that measure 10% or higher of the ex vivo radioactive count of the hottest sentinel node should be harvested for optimal detection of nodal metastases.

Significance of plasma cytokine levels in melanoma patients with histologically negative sentinel lymph nodes.

INTRODUCTION: Although sentinel lymph node (SLN) status is the most powerful predictor of prognosis in patients with clinically localized melanoma, a proportion of melanoma patients with histologically negative SLNs will still recur. It is hypothesized that tumor response may be altered or mediated by specific cytokines. We therefore investigated whether levels of IL-4, IL-6, IL-10, TNF-alpha, or IFN-gamma would predict disease recurrence in melanoma patients with histologically negative SLNs. METHODS: This prospective cohort study involved 218 patients with clinically localized melanoma who underwent a histologically negative SLN biopsy. Preoperative plasma cytokine levels were determined by enzyme-linked immunosorbent assay on these patients, as well as on 90 healthy controls. Kaplan-Meier life tables were constructed, and Cox proportional hazards analyses were performed to assess predictors of disease-free survival (DFS). RESULTS: At a median follow-up of 43 months, 33 of 218 patients (15%) had suffered disease recurrence. Melanoma patients had significant elevations of IL-4, IL-6, and IL-10 compared to healthy controls; levels of IFN-gamma were less elevated in melanoma patients compared to controls. Despite this, melanoma patients with detectable IFN-gamma levels were at significantly higher risk for recurrence compared to patients with undetectable levels (5-year DFS 70% vs. 86%, P = .03). On multivariate analysis including standard melanoma prognostic factors, only tumor thickness (P = .004) and the presence of detectable IFN-gamma levels (P = .05) were significant independent prognostic factors for disease-free survival. CONCLUSIONS: Among melanoma patients with clinically localized disease who have undergone a histologically negative SLN biopsy, presence of a detectable plasma level of IFN-gamma is an independent predictor of disease recurrence. Elevated levels of IFN-gamma may identify a group of early-stage melanoma patients who are more likely to have recurrence of disease and who may benefit from adjuvant therapies, including immunotherapies.

Improved staging of node-negative patients with intermediate to thick melanomas (>1 mm) with the use of lymphatic mapping and sentinel lymph node biopsy.

BACKGROUND: Elective lymph node dissection (ELND) may contribute to a survival benefit in certain stratified subsets of melanoma patients. We hypothesized that lymphatic mapping and sentinel lymph node (SLN) biopsy (with complete node dissection if metastases are present) may improve both staging and survival of patients with clinically negative nodes, without subjecting all patients to the morbidity associated with complete ELND. METHODS: We reviewed the data for all 14,914 N0 patients of the AJCC Melanoma Staging Database to determine the effect of SLN biopsy and ELND on staging and survival. RESULTS: Retrospective analysis revealed that there was an apparent statistically significant survival advantage to SLN biopsy in patients with melanomas > 1 mm (n = 9024; 68.5% and 26.2% reduction in mortality compared with patients staged to be N0 by clinical exam and ELND, respectively; P < .0001). Five-year survivals were 90.5%, 77.7%, and 69.8%, respectfully, for patients staged by SLN biopsy (n = 2552), ELND (n = 2014), and clinical examination alone (n = 5192). The survival advantage of SLN biopsy was statistically significant for each T-stage category (T2, T3, and T4) and ulceration status. There was no advantage to SLN biopsy in patients with melanomas <1 mm (n = 5890). CONCLUSIONS: SLN biopsy provides more accurate staging and may contribute to a survival benefit in populations of patients with melanoma.