Sentinel node biopsy is indicated for thin melanomas ≥0.76 mm

Management of melanoma: can we use gene expression profiling to help guide treatment and surveillance?

Although the incidence of cutaneous melanoma (CM) has been increasing annually, the mortality rate has been decreasing, likely due to better prevention, earlier detection, improved surveillance, and the development of new therapies. Current clinical management guidelines by the National Comprehensive Cancer Network (NCCN) are based on patient risk assignment using staging criteria established by the American Joint Committee on Cancer (AJCC). However, some patients with localized disease (stage I-II), generally considered to have a good prognosis, will develop metastatic disease and die, whereas some patients with later stage disease (stage III-IV) will be cured by surgery, adjuvant therapy, and/or systemic therapy. These results emphasize the importance of identifying patients whose risk may be over or underestimated with standard staging. Gene expression profile (GEP) tests are noninvasive molecular tests that assess the expression levels of a panel of validated genes, providing information about tumor prognosis, including the risk of recurrence, metastasis, and cancer-specific death. GEP tests can provide prognostic information beyond standard staging that may aid clinicians and patients in treatment and surveillance management decisions. This review describes how combining clinicopathologic staging with a robust assessment of tumor biology may provide information that will allow more refined intervention and long-term management.

Melanoma progression and prognostic models drawn from single-cell, spatial maps of benign and malignant tumors

Melanoma clinical outcomes emerge from incompletely understood genetic mechanisms operating within the tumor and its microenvironment. Here, we used single-cell RNA-based spatial molecular imaging (RNA-SMI) in patient-derived archival tumors to reveal clinically relevant markers of malignancy progression and prognosis. We examined spatial gene expression of 203,472 cells inside benign and malignant melanocytic neoplasms, including melanocytic nevi and primary invasive and metastatic melanomas. Algorithmic cell clustering paired with intratumoral comparative two-dimensional analyses visualized synergistic, spatial gene signatures linking cellular proliferation, metabolism, and malignancy, validated by protein expression. Metastatic niches included up-regulation of CDK2 and FABP5, which independently predicted poor clinical outcome in 473 patients with melanoma via Cox regression analysis. More generally, our work demonstrates a framework for applying single-cell RNA-SMI technology toward identifying gene regulatory landscapes pertinent to cancer progression and patient survival.

Predictive Values of Pathological and Clinical Risk Factors for Positivity of Sentinel Lymph Node Biopsy in Thin Melanoma: A Systematic Review and Meta-Analysis

Background

The indications for sentinel lymph node biopsy (SLNB) for thin melanoma are still unclear. This meta-analysis aims to determine the positive rate of SLNB in thin melanoma and to summarize the predictive value of different high-risk features for positive results of SLNB.

Methods

Four databases were searched for literature on SLNB performed in patients with thin melanoma published between January 2000 and December 2020. The overall positive rate and positive rate of each high-risk feature were calculated and obtained with 95% confidence intervals (CIs). Both unadjusted odds ratios (ORs) and adjusted ORs (AORs) of high-risk features were analyzed. Pooled effects were estimated using random-effects model meta-analyses.

Results

Sixty-six studies reporting 38,844 patients with thin melanoma who underwent SLNB met the inclusion criteria. The pooled positive rate of SLNB was 5.1% [95% confidence interval (CI) 4.9%-5.3%]. Features significantly predicted a positive result of SLNB were thickness≥0.8 mm [AOR 1.94 (95%CI 1.28-2.95); positive rate 7.0% (95%CI 6.0-8.0%)]; ulceration [AOR 3.09 (95%CI 1.75-5.44); positive rate 4.2% (95%CI 1.8-7.2%)]; mitosis rate >0/mm2 [AOR 1.63 (95%CI 1.13-2.36); positive rate 7.7% (95%CI 6.3-9.1%)]; microsatellites [OR 3.8 (95%CI 1.38-10.47); positive rate 16.6% (95%CI 2.4-36.6%)]; and vertical growth phase [OR 2.76 (95%CI 1.72-4.43); positive rate 8.1% (95%CI 6.3-10.1%)].

Conclusions

The overall positive rate of SLNB in thin melanoma was 5.1%. The strongest predictor for SLN positivity identified was microsatellites on unadjusted analysis and ulceration on adjusted analysis. Breslow thickness ≥0.8 mm and mitosis rate >0/mm² both predict SLN positivity in adjusted analysis and increase the positive rate to 7.0% and 7.7%. We suggest patients with thin melanoma with the above high-risk features should be considered for giving an SLNB.

Sentinel lymph node biopsy in melanoma: beyond histologic factors

Sentinel lymph node (SLN) biopsy should be performed with the technical expertise required to correctly identify the sentinel node, in the context of understanding both the likelihood of positivity in a given patient and the prognostic significance of a positive or negative result. National Comprehensive Cancer Network guidelines recommend SLN biopsy for all cutaneous melanoma patients with primary tumor thickness greater than 1 mm and in select patients with thickness between 0.8 and 1 mm, yet admit a lack of consistent clarity in its utility for prognosis and therapeutic value in tumors < 1 mm and leave the decision for undergoing the procedure up to the patient and treating physician. Recent studies have evaluated specific patient populations, tumor histopathologic characteristics, and gene expression profiling and their use in predicting SLN positivity. These data have given insight into improving the physician's ability to potentially predict SLN positivity, shedding light on if and when omission of SLN biopsy in specific patients based on clinicopathological characteristics might be appropriate. This review provides discussion and insight into these recent advancements.

Use and Costs of Sentinel Lymph Node Biopsy in Non-Ulcerated T1b Melanoma: Analysis of a Population-Based Registry

BACKGROUND

The utility of sentinel lymph node biopsy (SLNB) for non-ulcerated T1b melanoma is debated and associated costs are poorly characterized. Prior work using institutional registries may overestimate the incidence of nodal positivity in this population.

OBJECTIVE

The aim of this study was to estimate the use of SLNB, positivity prevalence, and procedural costs in patients with non-ulcerated T1b melanoma using a population-based registry.

METHODS

We identified patients with clinically node-negative, non-ulcerated melanoma 0.8-1.0 mm thick (T1b according to the 8th edition standard of the American Joint Committee on Cancer) in the Surveillance, Epidemiology, and End Results database from 2010 to 2016. The prevalence of SLNB procedures and positive sentinel nodes were calculated. Factors associated with SLNB and sentinel node positivity were assessed using logistic regression. Medicare reimbursement costs and patient out-of-pocket expenses for SLNB and wide local excision (WLE) versus WLE alone were estimated.

RESULTS

Among 7245 included patients, 3835(53%) underwent SLNB, 156 (4.1%, 95% confidence interval 3.5-4.7) of whom had a positive SLNB. Younger age, >1 mitosis per mm², female sex, and truncal tumor location were associated with higher odds of positivity. The estimated SLNB cost to identify one patient with stage III disease was $71,700 (range $54,648-$83,172). Out-of-pocket expenses for a Medicare patient were estimated to be $652 for a WLE and SLNB and $79 for a WLE alone.

CONCLUSIONS

In this population-based study, only 4% of selected non-ulcerated T1b patients had a positive SLNB, which is lower than prior reports. At the population level, SLNB is associated with high costs per prognostic information gained.

Re-evaluation of Sentinel Lymph Node Biopsy for Melanoma

OPINION STATEMENT

The vast majority of patients newly diagnosed with melanoma present with clinically localized disease, and sentinel lymph node biopsy (SLNB) is a standard of care in the management of these patients, particularly in intermediate thickness cases, in order to provide important prognostic data. However, SLNB also has an important role in the management of patients with other subtypes of melanoma such as thick melanomas, certain thin melanomas, and specific histologic variants of melanoma such as desmoplastic melanoma. Furthermore, there have been technical advances in the SLNB technique, such as the development of newer radiotracers and use of SPECT/CT, and there is some data to suggest performing a SLNB may be therapeutic. Finally, the management of patients with a positive sentinel lymph node (SLN) has undergone dramatic changes over the past several years based on the results of recent important clinical trials. Treatment options for patients with SLN metastases now include surveillance, completion lymph node dissection, and adjuvant therapy with checkpoint inhibitors and targeted therapy. SLNB continues to play a crucial role in the management of patients with melanoma, allowing for risk stratification, potential regional disease control, and further treatment options for patients with a positive SLN.

Association of the Affordable Care Act's Medicaid expansion with the diagnosis and treatment of clinically localized melanoma: A National Cancer Database study

BACKGROUND

The Affordable Care Act's Medicaid expansion is associated with earlier diagnosis and improved care among lower socioeconomic status populations with cancer, but its impact on melanoma is undefined.

OBJECTIVE

To determine the association of Medicaid expansion with stage of diagnosis and use of sentinel lymph node biopsy in nonelderly adult patients with newly diagnosed clinically localized melanoma.

METHODS

Quasi-experimental, difference-in-differences retrospective cohort analysis using data from the National Cancer Database from 2010 to 2017. Patients from expansion versus nonexpansion states and diagnosed before (2010-2013) versus after (2014-2017) expansion were identified.

RESULTS

Of 83,322 patients, 46.6% were female, and the median age was 55 years (interquartile range, 49-60). After risk adjustment, Medicaid expansion was associated with a decrease in the diagnosis of T1b stage or higher melanoma (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.88-0.98; P = .011) and decrease in uninsured status (OR, 0.61; 95% CI, 0.52-0.72; P < .001) but was not associated with a difference in sentinel lymph node biopsy performance when indicated (OR, 1.06; 95% CI, 0.95-1.20; P = .29).

LIMITATIONS

Retrospective study using a national database.

CONCLUSION

In this study of patients with clinically localized melanoma, Medicaid expansion was associated with a decrease in the diagnosis of later T-stage tumors.

Prognostic Significance of Subungual Anatomic Site in Acral Lentiginous Melanoma

CONTEXT.—

Acral lentiginous melanoma is a rare and aggressive type of cutaneous melanoma that arises on the acral skin and the nail unit. The prognostic significance of subungual anatomic site in acral lentiginous melanoma is not established.

OBJECTIVE.—

To assess the impact of subungual anatomic site on overall survival and disease-specific survival in acral lentiginous melanoma.

DESIGN.—

Retrospective cohort analysis. Clinicopathologic characteristics of 627 primary acral lentiginous melanomas (45 [7%] subungual and 582 [93%] nonsubungual) were summarized, and the impact of these characteristics on overall survival and disease-specific survival was determined using univariate and multivariable analyses.

RESULTS.—

No significant differences in clinicopathologic features were identified between the subungual and nonsubungual acral lentiginous melanomas. The 1-, 5-, and 10-year overall survival rates were 81%, 40%, and 28%, respectively, for subungual acral lentiginous melanoma and 94%, 59%, and 38%, respectively, for nonsubungual acral lentiginous melanoma (P = .04); risk of death was significantly higher for subungual tumors (hazard ratio [95% confidence interval] = 1.59 [1.02-2.50]; P = .04). The 1-, 5-, and 10-year disease-specific survival rates were 94%, 56%, and 48%, respectively, for subungual acral lentiginous melanoma versus 96%, 69%, and 55%, respectively, for nonsubungual acral lentiginous melanoma (P = .18). By multivariable analysis, independent poor prognostic factors included older age and ulceration for overall survival and greater Breslow thickness and sentinel lymph node positivity for overall survival and disease-specific survival. Subungual anatomic site was not an independent prognostic factor for overall or disease-specific survival.

CONCLUSIONS.—

Subungual anatomic site is not an independent prognostic factor for acral lentiginous melanoma.

Aggressive Digital Papillary Adenocarcinoma Mimicking a Giant Cell Tumour - A Case Report and Review of the Literature

Aggressive digital papillary adenocarcinoma (ADPAca) is a rare, underreported, and often misdiagnosed malignant tumour of the eccrine sweat gland, with high recurrence and metastatic potential. We present a case of a painless mass over the middle phalanx of the dominant index finger in a 51-year-old man. The mass was present for over 20 years, which had slowly increased in size. The patient only presented when it began to interfere with his profession as an electrician. The clinical presentation was consistent with a giant cell tumour. Histological diagnosis was of an ADPAca. Staging investigations were negative and he subsequently went on to have a ray amputation. The importance of high clinical suspicion of digit lesions is highlighted. No specific histologic features have been identified to predict recurrence or metastasis. We review the merits of performing sentinel node biopsy and alternative treatment options such as Moh’s micrographic surgery. We review the international literature to assess metastatic potential and follow-up requirements.

Is it Necessary to Perform Sentinel Lymph Node Biopsy in Thin Melanoma? A Retrospective Single Center Analysis

Sentinel lymph node biopsy (SLNB) is a standard procedure for regional lymph node staging and still has the most important prognostic value for the outcome of patients with thin melanoma. In addition to ulceration, SLNB had to be considered even for a single mitotic figure in thin (<1 mm) melanoma according to AJCC7th guideline, therefore, a retrospective review was conducted involving 403 pT1 melanoma patients. Among them, 152 patients suffered from pT1b ulcerated or mitotic rate ≥ 1/ mm2 melanomas according to the AJCC7th staging system. SLNB was performed in 78 cases, of which nine (11.5%) showed SLN positivity. From them, interestingly, we found a relatively high positive sentinel rate (6/78-8%) in the case of thin primary melanomas ˂0.8 mm. Moreover, the presence of regression increased the probability of sentinel positivity by 5.796 fold. After reassessing pT stage based on the new AJCC8th, 37 pT1b cases were reordered into pT1a category. There was no significant relation between other characteristics examined (age, gender, Breslow, Clark level, and mitosis index) and sentinel node positivity. Based on our data, we suggest that mitotic rate alone is not a sufficiently powerful predictor of SLN status in thin melanomas. If strict histopathological definition criteria are applied, regression might be an additional adverse feature that aids in identifying T1 patients most likely to be SLN-positive. After reassessing of pT1b cases according to AJCC8th regression proved to be independent prognostic factor on sentinel lymph node positivity. Our results propose that sentinel lymph node biopsy might also be considered at patients with regressive thin (˂0.8 mm) melanomas.

Sentinel Lymph Node Biopsy for T1b Melanoma: Balancing Prognostic Value and Cost

BACKGROUND

The purpose of this study is to report the additional prognostic information and cost associated with sentinel lymph node biopsy (SLNB) for patients with T1b melanoma.

PATIENTS AND METHODS

An institutional database was queried for patients with T1b melanoma (0.8-1.0 mm or < 0.8 mm with ulceration) with at least 5 years of follow-up. Results of SLNB, completion lymphadenectomy (CLND), recurrence, and melanoma-specific survival (MSS) were assessed. Institutional costs of melanoma care were converted to Medicare proportional dollars. A Markov model was created to estimate long-term costs.

RESULTS

Among the total 392 patients, 238 underwent SLNB. Median follow-up was 10.5 years. SLNB was positive in 19 patients (8.0%). Patients who underwent SLNB had higher 10-year nodal recurrence-free survival (98.6% vs. 91.2%, p < 0.001) but not MSS (94.4% vs. 93.2%, p = 0.55). Ulceration (HR 4.7, p = 0.022) and positive sentinel node (HR 11.5, p < 0.001) were associated with worse MSS. Estimates for 5-year costs reflect a fourfold increase in total costs of care associated with SLNB. However, a treatment plan that forgoes adjuvant therapy for resected stage IIIA melanoma but offers systemic therapy for a node-basin recurrence would nullify the additional cost of SLNB.

CONCLUSIONS

SLNB is prognostic for T1b melanoma. Its impact on the overall cost of melanoma care is intimately tied to systemic therapy in the adjuvant and recurrent settings.

Early Melanoma Nodal Positivity and Biopsy Rates Before and After Implementation of the 7th Edition of the AJCC Cancer Staging Manual

Importance

There has been a continued increase in the incidence of newly diagnosed melanomas, most of which are T1 melanomas. The associations between changes in tumor staging, implemented with the 7th edition of the AJCC Cancer Staging Manual (AJCC 7), and sentinel lymph node biopsy rates and nodal positivity rates remain to be seen.

Objective

To evaluate the change that the implementation of the AJCC 7 had on staging criteria and the distribution of thin melanomas requiring nodal surgery and nodal positivity rates.

Design, Setting, and Participants

Retrospective cross-sectional study from 2004 through 2013 of all adults (≥18 years) diagnosed with a T1 (Breslow depth ≤1.0 mm) melanoma using The National Cancer Database that captures 70% of all newly diagnosed cancers from accredited Commission on Cancer organizations, including both academic and community settings. Data were analyzed in May 2017.

Exposures

Patients were grouped together based on year of diagnosis, before and after 2009.

Main Outcomes and Measures

To determine the sentinel lymph node biopsy rate before and after the implementation of the AJCC 7.

Results

A total of 141 280 patients met inclusion criteria. Of 86 846 patients diagnosed from 2004 through 2009, 53.7% (49 644) were male and had a mean (SD) age of 57.7 (16.4) years. Of 54 434 patients diagnosed from 2010 through 2013, 54.3% (31 086) were male and had a mean (SD) age of 59.5 (15.9) years. After 2010, there was a 3.8% decrease in the number of nodal surgeries performed (32 485 of 86 846 patients [37.6%] vs 18 379 of 54 434 patients [33.8%]; P < .001). The nodal positivity rate decreased 1.0% from (9.8% [3166 of 86 846] to 8.8% [1618 of 54 434]) (P < .001). An increase in the proportion of T1b melanomas being evaluated, from 48.8% to 62.2%, was seen (P < .001). Of T1b melanomas that underwent nodal evaluation from 2004 through 2009, 74.0% had Clark level IV (invasion of the reticular dermis) or Clark level V (invasion of the deep, subcutaneous tissue) and 9.5% were ulcerated. From 2010 through 2013, of the T1b melanomas undergoing nodal evaluation, 82.6% had an elevated mitotic rate only, 3.7% were ulcerated, and 13.7% had both ulceration and an elevated mitotic rate.

Conclusions and Relevance

It appears that after the institution of AJCC 7, there was an overall decrease in the number of T1 melanomas undergoing nodal biopsy without a clinically relevant change in sentinel lymph node positivity, with an increase in the number of T1b melanomas undergoing nodal evaluation.

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

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

A nomogram to predict node positivity in patients with thin melanomas helps inform shared patient decision making

OBJECTIVE

To develop a nomogram to estimate the probability of positive sentinel lymph node (+SLN) for patients with thin melanoma and to characterize its potential impact on sentinel lymph node biopsy (SLNB) rates.

METHODS

Patients diagnosed with thin (0.5-1.0 mm) melanoma were identified from the National Cancer Database 2012 to 2015. A multivariable logistic regression model was used to examine factors associated with +SLN, and a nomogram to predict +SLN was constructed. Nomogram performance was evaluated and diagnostic test statistics were calculated.

RESULTS

Of the 21 971 patients included 10 108 (46.0%) underwent SLNB, with a 4.0% +SLN rate. On multivariable analysis, age, Breslow thickness, lymphovascular invasion, ulceration, and Clark level were significantly associated with SLN status. The area under the receiver operating curve was 0.67 (95% confidence interval, 0.65-0.70). While 15 249 (69.4%) patients had either T1b tumors or T1a tumors with at least one adverse feature, only 2846 (13.0%) had a nomogram predicted probability of a +SLN ≥5%. Using this cut-off, the indication for a SLNB in these patients would be reduced by 81.3% as compared to the American Joint Committee on Cancer 8th edition staging criteria.

CONCLUSIONS

The risk predictions obtained from the nomogram allow for more accurate selection of patients who could benefit from SLNB.

Re-biopsy of partially sampled thin melanoma impacts sentinel lymph node sampling as well as surgical margins

AIM

To assess the impact of re-biopsy on partially sampled melanoma in situ (MIS), atypical melanocytic proliferation (AMP) and thin invasive melanoma.

MATERIALS & METHODS

We retrospectively identified cases of re-biopsied partially sampled neoplasms initially diagnosed as melanoma in situ, AMP or thin melanoma (Breslow depth ≤0.75 mm).

RESULTS & CONCLUSION

Re-biopsy led to sentinel lymph node biopsy (SLNB) in 18.3% of cases. No patients upstaged from AMP or MIS had a positive SLNB. One out of nine (11.1%) initially diagnosed as a thin melanoma ≤0.75 mm, upstaged with a re-biopsy, had a positive SLNB. After re-biopsy 8.5% underwent an increased surgical margin. Selective re-biopsy of partially sampled melanoma with gross residual disease can increase the accuracy of microstaging and optimize treatment regarding surgical margins and SLNB.

Association between tumor-infiltrating lymphocytes and sentinel lymph node positivity in thin melanoma

BACKGROUND

Sentinel lymph node biopsy in thin invasive primary cutaneous melanoma (up to 1mm thick) is a controversial subject. The presence of tumor-infiltrating lymphocytes could be a factor to be considered in the decision to perform this procedure.

OBJECTIVE

To evaluate the association between the presence of tumor-infiltrating lymphocytes and lymph node metastases caused by thin primary cutaneous melanoma.

METHODS

Cross-sectional study with 137 records of thin invasive primary cutaneous melanoma submitted to sentinel lymph node biopsy from 2003 to 2015. The clinical variables considered were age, sex and topography of the lesion. The histopathological variables assessed were: tumor-infiltrating lymphocytes, melanoma subtype, Breslow thickness, Clark levels, number of mitoses per mm2, ulceration, regression and satellitosis. Univariate analyzes and logistic regression tests were performed as well the odds ratio and statistical relevance was considered when p <0.05.

RESULTS

Among the 137 cases of thin primary cutaneous melanoma submitted to sentinel lymph node biopsy, 10 (7.3%) had metastatic involvement. Ulceration on histopathology was positively associated with the presence of metastatic lymph node, with odds ratio =12.8 (2.77-59.4 95% CI, p=0.001). The presence of moderate/marked tumor-infiltrating lymphocytes was shown to be a protective factor for the presence of metastatic lymph node, with OR=0.20 (0.05-0.72 95% CI, p=0.014). The other variables - clinical and histopathological - were not associated with the outcome.

STUDY LIMITATIONS

The relatively small number of positive sentinel lymph node biopsy may explain such an expressive association of ulceration with metastatization.

CONCLUSIONS

In patients with thin invasive primary cutaneous melanoma, few or absent tumor-infiltrating lymphocytes, as well as ulceration, represent independent risk factors for lymph node metastasis.

Vertical Growth Phase as a Prognostic Factor for Sentinel Lymph Node Positivity in Thin Melanomas: A Systematic Review and Meta-Analysis

BACKGROUND

The 2010 American Joint Committee on Cancer guidelines recommended consideration of sentinel lymph node biopsy for thin melanoma (Breslow thickness <1.0 mm) with aggressive pathologic features such as ulceration and/or high mitotic rate. The therapeutic benefit of biopsy-based treatment remains controversial. The authors conducted a meta-analysis to estimate the risk and outcomes of sentinel lymph node positivity in thin melanoma, and examined established and potential novel predictors of positivity.

METHODS

Three databases were searched by two independent reviewers for sentinel lymph node positivity in patients with thin melanoma. Study heterogeneity, publication bias, and quality were assessed. Data collected included age, sex, Breslow thickness, mitotic rate, ulceration, regression, Clark level, tumor-infiltrating lymphocytes, and vertical growth phase. Positivity was estimated using a random effects model. Association of positivity and clinicopathologic features was investigated using meta-regression.

RESULTS

Ninety-three studies were identified representing 35,276 patients with thin melanoma who underwent sentinel lymph node biopsy. Of these patients, 952 had a positive sentinel lymph node biopsy, for an event rate of 5.1 percent (95 percent CI, 4.1 to 6.3 percent). Significant associations were identified between positivity and Breslow thickness greater than 0.75 mm but less than 1.0 mm, mitotic rate, ulceration, and Clark level greater than IV. Seven studies reported on vertical growth phase, which was strongly associated with positivity (OR, 4.3; 95 percent CI, 2.5 to 7.7).

CONCLUSIONS

To date, this is the largest meta-analysis to examine predictors of sentinel lymph node biopsy positivity in patients with thin melanoma. Vertical growth phase had a strong association with biopsy positivity, providing support for its inclusion in standardized pathologic reporting.

Nonvisualization of Sentinel Lymph Nodes by Lymphoscintigraphy in Primary Cutaneous Melanoma: Incidence, Risk Factors, and a Review of Management Options

BACKGROUND

Lymphoscintigraphy is often performed before sentinel lymph node biopsy, especially in areas likely to have multiple or aberrant drainage patterns. This study aims to determine the incidence and characteristics of melanoma patients with negative lymphoscintigraphic findings and to review the management options and surgical recommendations.

METHODS

This is a retrospective study of patients with primary cutaneous melanoma who underwent sentinel lymph node biopsy between 2005 and 2016. Patients with nonvisualized lymph nodes on preoperative lymphoscintigraphy were compared in a 1:4 ratio with a randomly selected unmatched cohort drawn from all melanoma patients who underwent preoperative lymphoscintigraphy within the period of the study. Demographic, clinical, and outcome data were compared between these groups.

RESULTS

A negative lymphoscintigraphic scan was seen in 2.3 percent of all cases (25 of 1073). In both univariate and multivariate analyses, predictive patient- and tumor-specific factors for negative lymphoscintigraphy included older age and head and neck location. Patients with a nonvisualized sentinel lymph node had significantly worse overall survival compared with patients who had a visualized sentinel lymph node, but there was no difference in melanoma-specific survival. In 16 of the 25 cases (64 percent), at least one sentinel lymph node was found intraoperatively despite the negative lymphoscintigraphic findings.

CONCLUSIONS

Older patients with head and neck melanomas are more likely to experience nodal nonvisualization on lymphoscintigraphy. In patients who have nodal nonvisualization, the surgeon should attempt sentinel lymph node biopsy at the time of excision of the primary lesion because a sentinel lymph node can still be found in a majority of cases, and it offers prognostic information.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

Metastases risk in thin cutaneous melanoma: prognostic value of clinical-pathologic characteristics and mutation profile

Background

A high percentage of patients with thin melanoma (TM), defined as lesions with Breslow thickness ≤1 mm, presents excellent long-term survival, however, some patients develop metastases. Existing prognostic factors cannot reliably differentiate TM patients at risk for metastases.

Objective

We aimed at characterizing the clinical-pathologic and mutation profile of metastatic and not-metastatic TM in order to distinguish lesions at risk of metastases.

Methods

Clinical-pathologic characteristics were recorded for the TM cases analyzed. We used a Next Generation Sequencing (NGS) multi-gene panel to characterize TM for multiple somatic mutations.

Results

A statistically significant association emerged between the presence of metastases and Breslow thickness ≥0.6 mm (p=0.003). None of TM with lymph-node involvement had Breslow thickness <0.6 mm. Somatic mutations were identified in 19 of 21 TM analyzed (90.5%). No mutations were observed in two not-metastatic cases with the lowest Breslow thickness (≤0.4 mm), whereas mutations in more than one gene were detected in one metastatic case with the highest Breslow thickness (1.00 mm).

Conclusion

Our study indicates Breslow thickness ≥0.6 mm as a valid prognostic factor to distinguish TM at risk for metastases.

Hospital-Based Study of Compliance with NCCN Guidelines and Predictive Factors of Sentinel Lymph Node Biopsy in the Setting of Thin Melanoma Using the National Cancer Database

Thin melanoma is the most common form of melanoma in the United States. The National Comprehensive Cancer Network (NCCN) has guidelines for sentinel lymph node biopsy (SLNB) which recommend “discuss and consider” SLNB for invasion >0.75 mm and “discuss and offer” SLNB for invasion >0.75 mm with suspicious features. This study looked at compliance with NCCN guidelines and factors that are predictive of a positive SLNB. This is a retrospective study of patients diagnosed with thin melanoma 2012–2013 using the National Cancer Database. A total of 26,456 patients met study qualifications. Univariate analysis showed that 76 per cent of patients meeting criteria underwent SLNB. Patients recommended to “discuss and consider” received SLNB 53 per cent of the time and those not recommended for SLNB received SLNB 20 per cent of the time. On multivariate analysis, depth was not predictive for positive SLNB whereas mitoses and ulceration were. Other factors predictive of positive SLNB were nodular cell type, lymphovascular invasion, and Clark's level greater than or equal to IV. Patients with thin melanoma that meet NCCN guidelines for SLNB undergo this procedure in good compliance but those who do not meet criteria continue to receive SLNB. Positive predictive factors for positive SLNB include mitoses, ulceration, Clark's level, and primary site.

Stratifying SLN incidence in intermediate thickness melanoma patients

BACKGROUND

Guidelines for melanoma recommend sentinel lymph node biopsy (SLNB) in patients with melanomas ≥1 mm thickness. Recent single institution studies have found tumors <1.5 mm a low-risk group for positive SLNB.

METHODS

A retrospective review of the Sentinel Lymph Node Working Group multicenter database identified patients with intermediate thickness melanoma (1.01-4.00 mm) who had SLNB, and assessed predictors for positive SLNB.

RESULTS

3460 patients were analyzed, 584 (17%) had a positive SLNB. Univariate factors associated with a positive SLNB included age <60 (p < .001), tumor on the trunk/lower extremity (p < .001), Breslow depth ≥2 mm (p < .001), ulceration (p < .001), mitotic rate ≥1/mm² (p = .01), and microsatellitosis (p < .001). Multivariate analysis revealed age, location, and Breslow depth as significant predictors. Patients ≥75 with lesions 1.01-1.49 mm on the head/neck/upper extremity and 1.5-1.99 mm without high-risk features had <5% risk of SLN positivity.

CONCLUSIONS

Intermediate thickness melanoma has significant heterogeneity of SLNB positivity. Low-risk subgroups can be found among older patients in the absence of high-risk features.

Transected thin melanoma: Implications for sentinel lymph node staging

BACKGROUND AND OBJECTIVES

Indications for sentinel lymph node (SLN) biopsy in patients with thin melanoma (≤1 mm thick) are controversial. We asked whether deep margin (DM) positivity at initial biopsy of thin melanoma is associated with SLN positivity.

METHODS

Cases were identified using prospectively maintained databases at two melanoma centers. Patients who had undergone SLN biopsy for melanoma ≤1 mm were included. DM status was assessed for association with SLN metastasis in univariate and multivariate analyses.

RESULTS

1413 cases were identified, but only 1129 with known DM status were included. 39% of patients had a positive DM on original biopsy. DM-positive and DM-negative patients did not differ significantly in primary thickness, ulceration, or mitotic activity. DM-positive and DM-negative patients had similar incidence of SLN metastasis (5.7% vs 3.5%; P = 0.07). Positive DM was not associated with SLN metastasis on univariate analysis (OR 1.69, 95% CI: 0.95-3.00, P = 0.07) or on multivariate analysis adjusted for Breslow depth, Clark level, mitotic rate, and ulceration (OR = 1.59, 95% CI: 0.89-2.85; P = 0.12).

CONCLUSIONS

For patients with thin melanoma, a positive DM on initial biopsy is not associated with risk of SLN metastasis, so DM positivity should not be considered an indication for SLN staging in an otherwise low-risk patient.

Use of Indocyanine Green for Sentinel Lymph Node Biopsy: Case Series and Methods Comparison

Introduction:

Sentinel lymph node biopsy is indicated for patients with biopsy-proven thickness melanoma greater than 1.0 mm. Use of lymphoscintigraphy along with vital blue dyes is the gold standard for identifying sentinel lymph nodes intraoperatively. Indocyanine green (ICG) has recently been used as a method of identifying sentinel lymph nodes. We herein describe a case series of patients who have successfully undergone ICG-assisted sentinel lymph node biopsy for melanoma. We compare 2 imaging systems that are used for ICG-assisted sentinel lymph node biopsy.

Methods:

Fourteen patients underwent ICG-assisted sentinel lymph node biopsy for melanoma using the SPY Elite system (Novadaq, Mississigua, Canada) and the Hamamatsu PDE-Neo probe system (Mitaka USA, Park City, Utah). We analyzed costs for 2 systems that utilize ICG for sentinel lymph node biopsies.

Results:

Intraoperative use of ICG for sentinel lymph node biopsies was successful in correctly identifying sentinel lymph nodes. There was no difference between the Hamamatsu PDE-Neo probe and SPY Elite systems in the ability to detect sentinel lymph nodes; however, the former was associated with a lower operating cost and ease of use compared with the latter.

Conclusion:

ICG-assisted sentinel lymph biopsy using the SPY Elite or the Hamamatsu PDE-Neo probe systems for melanoma are comparable in terms of sentinel node detection. The Neo probe system delivers pertinent clinical data with the advantages of lower cost and ease of operation.

Analysis of sentinel node positivity in primary cutaneous melanoma: an 8-year single institution experience

BACKGROUND

Sentinel lymph node biopsy (SLNB) is a standard method for determining the pathologic status of the regional lymph nodes.

AIMS

The aim of our study was to determine the incidence and clinicopathologic factors predictive of SLN positivity, and to evaluate the prognostic importance of SLNB in patients with cutaneous melanoma.

METHODS

We performed a retrospective analysis of a prospectively maintained database of all patients who underwent SLNB for primary melanoma at our institution from 2005 to 2012. Statistical analysis was performed using χ 2 and Fischer exact test.

RESULTS

In total, 318 patients underwent SLNB, of which 65 were for thin melanoma (≤1 mm). There were 36 positive SLNB, 278 negative SLNB and in four cases the SLN was not located. The incidence rate for SLNB was 11.3% overall and 1.5% in thin melanomas alone. Statistical analysis identified Breslow thickness >1 mm (P = 0.006), Clark level ≥ IV (P = 0.004) and age <75 years (P = 0.035) as the strongest predictors of SLN positivity. Our overall false negativity rate was 20% (9/45) with one case of false-negative SLNB in thin melanomas.

CONCLUSION

Breslow thickness of the primary tumour remains the strongest predictor of SLN positivity. Our findings point to a possible limited role for SLNB in thin melanoma due to its low positivity rate, associated false-negative rate and related morbidity.

Targeting the duality of cancer

Cancer is the second leading cause of death in the United States, and is an increasing cause of death in the developing world. While there is great heterogeneity in the anatomic site and mutations involved in human cancer, there are common features, including immortal growth, angiogenesis, apoptosis evasion, and other features, that are common to most if not all cancers. However, new features of human cancers have been found as a result of clinical use of novel “targeted therapies,” angiogenesis inhibitors, and immunotherapies, including checkpoint inhibitors. These findings indicate that cancer is a moving target, which can change signaling and metabolic features based upon the therapies offered. It is well-known that there is significant heterogeneity within a tumor and it is possible that treatment might reduce the heterogeneity as a tumor adapts to therapy and, thus, a tumor might be synchronized, even if there is no major clinical response. Understanding this concept is important, as concurrent and sequential therapies might lead to improved tumor responses and cures. We posit that the repertoire of tumor responses is both predictable and limited, thus giving hope that eventually we can be more effective against solid tumors. Currently, among solid tumors, we observe a response of 1/3 of tumors to immunotherapy, perhaps less to angiogenesis inhibition, a varied response to targeted therapies, with relapse and resistance being the rule, and a large fraction being insensitive to all of these therapies, thus requiring the older therapies of chemotherapy, surgery, and radiation. Tumor phenotypes can be seen as a continuum between binary extremes, which will be discussed further. The biology of cancer is undoubtedly more complex than duality, but thinking of cancer as a duality may help scientists and oncologists discover optimal treatments that can be given either simultaneously or sequentially.

Brazilian guidelines for diagnosis, treatment and follow-up of primary cutaneous melanoma - Part II

The last Brazilian guidelines on melanoma were published in 2002. Development in diagnosis and treatment made updating necessary. The coordinators elaborated ten clinical questions, based on PICO system. A Medline search, according to specific MeSH terms for each of the 10 questions was performed and articles selected were classified from A to D according to level of scientific evidence. Based on the results, recommendations were defined and classified according to scientific strength. The present Guidelines were divided in two parts for editorial and publication reasons. In this second part, the following clinical questions were answered: 1) which patients with primary cutaneous melanoma benefit from sentinel lymph node biopsy? 2) Follow-up with body mapping is indicated for which patients? 3) Is preventive excision of acral nevi beneficious to patients? 4) Is preventive excision of giant congenital nevi beneficious to patients? 5) How should stages 0 and I primary cutaneous melanoma patients be followed?

Regression in thin melanoma is associated with nodal recurrence after a negative sentinel node biopsy

Prognostic markers for nodal metastasis in thin melanoma patients are debated. We present a single institution study looking at factors predictive of nodal disease in thin melanoma patients. Retrospective review from 1997 to 2012 identified 252 patients with thin melanoma (≤1 mm) who underwent a sentinel lymph node biopsy (SLNB). Node‐positive patients included positive SLNB patients and negative SLNB patients who developed a nodal recurrence (false‐negative SLNB). Clinicopathologic characteristics were correlated with nodal status and outcome. Median follow‐up was 45.5 months. Twelve of 252 patients (4.8%) were node‐positive including six positive SLNB (2.4%) and six false‐negative SLNB (2.4%) patients. No clinicopathologic factors were significantly correlated with nodal disease. For the six false‐negative SLNB patients, median time to nodal recurrence was 37.5 months. Regression was seen in only 16% of cases, but the rate increased to 60% for false‐negative SLNB cases. Both age (odds ratio [OR]: 1.09, 95% CI: 1.01–1.17; P = 0.02) and regression (OR: 8.33, 95% CI: 1.34–52.63; P = 0.02) were significantly associated with nodal recurrence after a negative SLNB on univariable analysis. Nodal disease in thin melanoma patients was seen in 4.8% of cases. Although regression was not correlated with nodal metastasis, it was correlated with a false‐negative SLNB. Patients with thin melanoma and regression may need more intensive surveillance after a negative SLNB. Further study is needed to determine if the same immune mechanisms that result in regression in primary tumors also lead to regression in lymph nodes, which may decrease detection of melanoma nodal metastases.

Malignant Melanoma: Beyond the Basics

LEARNING OBJECTIVES

After reading this article, the participant should be able to: 1. Discuss the initial management of cutaneous malignant melanoma with regard to diagnostic biopsy and currently accepted resection margins. 2. Be familiar with the management options for melanoma in specific situations such as subungual melanoma, auricular melanoma, and melanoma in the pregnant patient. 3. Discuss the differentiating characteristics of desmoplastic melanoma and its treatment options. 4. List the indications for sentinel lymph node biopsy and be aware of the ongoing trials and current literature. 5. Discuss the medical therapies available to patients with metastatic melanoma.

SUMMARY

Management of the melanoma patient is a complex and evolving subject. Plastic surgeons should be aware of the recent changes in the field. Excisional biopsy remains the gold standard for diagnosis, although there is no evidence that use of other biopsy types alters survival or recurrence. Wide local excisions should be carried out with margins as recommended by National Comprehensive Cancer Network guidelines according to lesion Breslow depth, with sentinel lymph node biopsy being offered to all medically suitable candidates with intermediate thickness melanomas (1.0 to 4.0 mm), and with sentinel lymph node biopsy being considered for high-risk lesions (ulceration and/or high mitotic figures) with melanomas of 0.75 to 1.0 mm. Melanomas diagnosed during pregnancy can be treated with preoperative lymphoscintigraphy and wide local excision under local anesthesia, with sentinel lymph node biopsy under general anesthesia delayed until after delivery. Management of desmoplastic melanoma is currently controversial with regard to the indications for sentinel lymph node biopsy and the efficacy of postoperative radiation therapy. Subungual and auricular melanoma have evolved from being treated by amputation of the involved appendage to less radical procedures-ear reconstruction is now attempted in the absence of gross invasion into the perichondrium, and subungual melanomas may be treated with wide local excision down to and including the periosteum, with immediate full-thickness skin grafting over bone. Although surgical treatment remains the current gold standard, recent advances in immunotherapy and targeted molecular therapy for metastatic melanoma show great promise for the development of medical therapies for melanoma.

Clinical utilities and biological characteristics of melanoma sentinel lymph nodes

An estimated 73870 people will be diagnosed with melanoma in the United States in 2015, resulting in 9940 deaths. The majority of patients with cutaneous melanomas are cured with wide local excision. However, current evidence supports the use of sentinel lymph node biopsy (SLNB) given the 15%-20% of patients who harbor regional node metastasis. More importantly, the presence or absence of nodal micrometastases has been found to be the most important prognostic factor in early-stage melanoma, particularly in intermediate thickness melanoma. This review examines the development of SLNB for melanoma as a means to determine a patient’s nodal status, the efficacy of SLNB in patients with melanoma, and the biology of melanoma metastatic to sentinel lymph nodes. Prospective randomized trials have guided the development of practice guidelines for use of SLNB for melanoma and have shown the prognostic value of SLNB. Given the rapidly advancing molecular and surgical technologies, the technical aspects of diagnosis, identification, and management of regional lymph nodes in melanoma continues to evolve and to improve. Additionally, there is ongoing research examining both the role of SLNB for specific clinical scenarios and the ways to identify patients who may benefit from completion lymphadenectomy for a positive SLN. Until further data provides sufficient evidence to alter national consensus-based guidelines, SLNB with completion lymphadenectomy remains the standard of care for clinically node-negative patients found to have a positive SLN.

Elevated Serum Leptin Levels are Associated With an Increased Risk of Sentinel Lymph Node Metastasis in Cutaneous Melanoma

The metabolic hormone leptin has been implicated in the pathogenesis of various malignancies and may contribute to the high rate of cancer in obese individuals. We reported that leptin and its receptor are expressed by melanoma tumors and cell lines, and that leptin stimulates proliferation of cultured melanoma cells. Here, we tested the hypothesis that leptin contributes to early melanoma progression by assessing its association with sentinel node positivity in cutaneous melanoma patients. The study enrolled 72 patients who were scheduled to undergo lymphatic mapping and sentinel node biopsy. Fasting blood was obtained before surgery, and serum leptin levels were measured by enzyme-linked immunosorbent assay (ELISA) with a "raw" (assay value) and an "adjusted" value (raw value divided by body mass index). Leptin levels and other clinicopathologic parameters were compared between sentinel node positive and negative groups. Logistic regression models were used to predict sentinel node status using leptin and other relevant clinical parameters. The raw and adjusted leptin levels were significantly higher in the 15 patients with positive sentinel nodes. These findings could not be attributed to differences in body mass indices. Univariate models revealed raw leptin, adjusted leptin, Breslow thickness, and mitotic rate as significant predictors of sentinel node status. Leptin levels and Breslow thickness remained significant in multivariate models. Survival and follow-up analysis revealed more aggressive disease in diabetic patients. Elevated serum leptin levels predict sentinel node metastasis in melanoma. Validation of this finding in larger cohorts should enable better stratification of early stage melanoma patients.

Sentinel Lymph Node Biopsy in Thin Cutaneous Melanoma: A Systematic Review and Meta-Analysis

BACKGROUND

Most patients with melanoma have a thin (≤1.00 mm) lesion. There is uncertainty as to which patients with thin melanoma should undergo sentinel lymph node (SN) biopsy. We sought to quantify the proportion of SN metastases in patients with thin melanoma and to determine the pooled effect of high-risk features of the primary lesion on SN positivity.

METHODS

Published literature between 1980 and 2015 was searched and critically appraised. Primary outcome was the proportion of SN metastases in patients with thin cutaneous melanoma. Secondary outcomes included the effect of high-risk pathological features of the primary lesion on the proportion of SN metastases. Summary measures were estimated by Mantel-Haenszel method using random effects meta-analyses.

RESULTS

Sixty studies (10,928 patients) met the criteria for inclusion. Pooled SN positivity was 4.5 % [95 % confidence interval (CI) 3.8-5.2 %]. Predictors of a positive SN were: thickness ≥0.75 mm [adjusted odds ratio (AOR) 1.90 (95 % CI 1.08-3.34); with a likelihood of SN metastases of 8.8 % (95 % CI 6.4-11.2 %)]; Clark level IV/V [AOR 2.24 (95 % CI 1.23-4.08); with a likelihood of 7.3 % (95 % CI 6.2-8.4 %)]; ≥1 mitoses/mm² [AOR 6.64 (95 % CI 2.77-15.88); pooled likelihood 8.8 % (95 % CI 6.2-11.4 %)]; and the presence of microsatellites [unadjusted OR 6.94 (95 % CI 2.13-22.60); likelihood 26.6 % (95 % CI 4.3-48.9 %)].

CONCLUSIONS

The pooled proportion of SN metastases in thin melanoma is 4.5 %. Thickness ≥0.75 mm, Clark level IV/V, mitoses, and microsatellites significantly increased the odds of SN positivity and should prompt strong consideration of SN biopsy.

Absence of Tumor-Infiltrating Lymphocyte Is a Reproducible Predictive Factor for Sentinel Lymph Node Metastasis: A Multicenter Database Study by the Brazilian Melanoma Group

Aims

The aim of this study is to confirm the function of tumor-infiltrating lymphocytes (TILs) in sentinel lymph node (SLN) metastasis.

Materials and Methods

This retrospective study included 633 patients with invasive melanoma who underwent sentinel lymph node biopsy in 7 referral centers certified by the Brazilian Melanoma Group. Independent risk factors of sentinel node metastasis (SNL) were identified by multiple logistic regression.

Results

SLN metastasis was detected in 101 of 633 cases (16.1%) and in 93 of 428 patients (21.7%) when melanomas ≤ 1mm were excluded. By multiple logistic regression, the absence of TILs was as an independent risk factor of SLN metastasis (OR = 1.8; 95%CI: 1.1–3.0), in addition to Breslow index (greater than 2.00 mm), lymph vascular invasion, and presence of mitosis.

Conclusion

SLNB can identify patients who might benefit from immunotherapy, and the determination of predictors of SLNB positivity can help select the proper population for this type of therapy. The absence of TILs is a reproducible parameter that can predict SLNB positivity in melanoma patients, since this study was made with several centers with different dermatopathologists.

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.

Tumor Cell Adhesion As a Risk Factor for Sentinel Lymph Node Metastasis in Primary Cutaneous Melanoma

PURPOSE

Less than 20% of patients with melanoma who undergo sentinel lymph node (SLN) biopsy based on American Society of Clinical Oncology/Society of Surgical Oncology recommendations are SLN positive. We present a multi-institutional study to discover new molecular risk factors associated with SLN positivity in thin and intermediate-thickness melanoma.

PATIENTS AND METHODS

Gene clusters with functional roles in melanoma metastasis were discovered by next-generation sequencing and validated by quantitative polymerase chain reaction using a discovery set of 73 benign nevi, 76 primary cutaneous melanoma, and 11 in-transit melanoma metastases. We then used polymerase chain reaction to quantify gene expression in a model development cohort of 360 consecutive thin and intermediate-thickness melanomas and a validation cohort of 146 melanomas. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. Logic and logistic regression analyses were used to develop a model for the likelihood of SLN metastasis from molecular, clinical, and histologic variables.

RESULTS

ITGB3, LAMB1, PLAT, and TP53 expression were associated with SLN metastasis. The predictive ability of a model that included these molecular variables in combination with clinicopathologic variables (patient age, Breslow depth, and tumor ulceration) was significantly greater than a model that only considered clinicopathologic variables and also performed well in the validation cohort (area under the curve, 0.93; 95% CI, 0.87 to 0.97; false-positive and false-negative rates of 22% and 0%, respectively, using a 10% cutoff for predicted SLN metastasis risk).

CONCLUSION

The addition of cell adhesion-linked gene expression variables to clinicopathologic variables improves the identification of patients with SLN metastases within 90 days of melanoma diagnosis.

Comparative effectiveness in melanoma

The worldwide incidence of melanoma continues to rise. It is a leading cause of cancer death and the second leading cause of loss of productive years of life. Although the diagnosis of melanoma is straightforward, there remain many controversies regarding treatment and surveillance. This chapter addresses important questions in melanoma treatment such as sentinel lymph node biopsy, what to do with a positive sentinel lymph node, margins of resection for melanoma, radiation for primary, nodal and metastatic melanoma, and routine use imaging. Through this chapter, the evidence for these controversial subjects and the barriers to resolution will be elucidated.

A review of sentinel lymph node biopsy for thin melanoma

INTRODUCTION

Although there is a lack of established survival benefit of sentinel lymph node biopsy (SLNB), this technique has been increasingly applied in the staging of patients with thin (≤1.00 mm) melanoma (T1Nx), without clear supportive evidence.

METHODS

We review the guidelines and available literature on the indications and rationale for performing SLNB in thin melanoma.

RESULTS

As a consequence of the paucity of evidence of SLNB in thin melanoma, there is considerable variability in the guidelines. It is difficult to define clinicopathologic factors that reliably predict the presence of nodal metastasis. SLNB does not yet inform management in thin melanoma to improve survival outcome.

CONCLUSION

Based on available evidence, high risk patients with melanomas between 0.75 and 1.00 mm may be appropriate candidates to be considered for SLN biopsy after discussing the likelihood of finding evidence of nodal progression, the risks of sentinel node biopsy, and the lack of proven survival benefit from any form of surgical nodal staging.

Analysis of tumor mitotic rate in thin metastatic melanomas compared with thin melanomas without metastasis using both the hematoxylin and eosin and anti-phosphohistone 3 IHC stain

Studies have suggested that elevated tumor mitotic rate (MR) is linked to overall survival in thin melanoma. Recently, promising data regarding anti-phosphohistone 3 (pHH3) immunohistochemistry and its ability to aid in calculation of MR have emerged. The authors retrospectively analyzed original biopsies from 13 thin melanomas with positive sentinel node (SN) status and 16 thin melanomas with negative SN status. Both anti-pHH3 immunohistochemistry and the hematoxylin and eosin (H&E) stain were used to evaluate MR by 2 dermatopathologists blinded to SN status using the "hot spot" method. Intraclass coefficient values were attained to measure interobserver concordance and reliability of the pHH3 stain. By generating a receiver operating characteristic curve and analyzing the overall area under the curve, pHH3 was found to have good interobserver reliability. The relationship between MR and SN involvement was also evaluated, but this correlation was not statistically significant.

Prediction of survival in patients with thin melanoma: results from a multi-institution study

PURPOSE

Cutaneous melanoma incidence is increasing. Most new cases are thin (≤ 1 mm) with favorable prognoses, but survival is nonetheless variable. Our aim was to investigate new prognostic factors and construct a nomogram for predicting survival in individual patients.

PATIENTS AND METHODS

Data from 2,243 patients with thin melanoma were retrieved from prospectively maintained databases at six centers. Kaplan-Meier survival and crude cumulative incidences of recurrence were estimated, and competing risks were taken into account. Multivariable Cox regression was used to investigate survival predictors.

RESULTS

Median follow-up was 124 months (interquartile range, 106 to 157 months); 12-year overall survival was 85.3% (95% CI, 83.4% to 87.2%). Median times to local, regional, and distant recurrence were 79, 78, and 107 months, respectively. Relapse was significantly related to age, Breslow thickness, mitotic rate (MR), ulceration, lymphovascular invasion (LVI), and regression; incidence was lower and subgroup differences were less marked for distant metastasis than for regional relapse. The worst prognosis categories were age older than 60 years, Breslow thickness more than 0.75 mm, MR ≥ 1, presence of ulceration, presence of LVI, and regression ≥ 50%. Breslow thickness more than 0.75 mm, MR ≥ 1, presence of ulceration, and LVI (all P = .001) were significantly associated with sentinel node positivity. Age, MR, ulceration, LVI, regression, and sentinel node status were independent predictors of survival and were used to construct a nomogram to predict 12-year overall survival. The nomogram was well calibrated and had good discriminative ability (adjusted Harrell C statistic, 0.88).

CONCLUSION

Our findings suggest including LVI and regression as new prognostic factors in the melanoma staging system. The nomogram appears useful for risk stratification in clinical management and for recruiting patients to clinical trials.

Recent developments in the medical and surgical treatment of melanoma

Increasing knowledge of the biology of melanoma has led to significant advances in drug development to fight this disease. Surgery is the primary treatment for localized disease and is an integral part of management in patients with more advanced disease. The last decade has become the era of targeted therapy in melanoma and has revolutionized the treatment of this disease. Since 2011, 4 new agents have been approved for the treatment of patients with metastatic melanoma: ipilimumab, vemurafenib, dabrafenib, and trametinib. Several new agents are currently in phase 3 trials with hopes of even more agents being approved for this once "untreatable" disease. How to integrate surgical options with more effective systemic therapies has become a new challenge for physicians. This review will provide an update on current surgical options, highlight the pathway to the development of the newly approved agents, and further discuss new treatments that are on the horizon.