Sentinel Lymph Node Biopsy and Management of Regional Lymph Nodes in Melanoma: American Society of Clinical Oncology and Society of Surgical Oncology Clinical Practice Guideline Update

Preoperative and Intraoperative Identification of Sentinel Lymph Nodes in Melanoma Surgery

According to the American Joint Commission on Cancer (AJCC) 8th edition guidelines, SLN biopsy is recommended for primary melanomas with a Breslow thickness of at least 1 mm. Additionally, the National Comprehensive Cancer Network (NCCN) recommends that a SLN biopsy may be considered for melanoma patients with T1b lesions, which are 0.8-1 mm thick or less than 0.8 mm thick with ulceration. It can also be considered for T1a lesions that are less than 0.8 mm thick but have other adverse features, such as a high mitotic rate, lymphovascular invasion, or a positive deep margin. To reduce the false negative rate of melanoma SLN biopsy, we have introduced the intraoperative use of Sentinella, a gamma camera, to enhance the identification rate of SLNs beyond that of the traditional gamma hand-held probe. At the Center for Melanoma Research and Treatment at the California Pacific Medical Center, a multidisciplinary approach has been established to treat melanoma patients when the diagnosis of primary melanoma is made with a referral to our melanoma center. This comprehensive approach at the melanoma tumor board, including the efforts of pathologists, radiologists, dermatologists, surgical, medical and radiation oncologists, results in a consensus to deliver personalized and high-quality care for our melanoma patients. This multidisciplinary program for the management of melanoma can be duplicated for other types of cancer. This article consists of current knowledge to document the published methods of identification of sentinel lymph nodes. In addition, we have included new data as developed in our melanoma center as newly published materials in this article to demonstrate the utility of these methods in melanoma sentinel lymph node surgery. Informed consent has been waived by our IRB regarding the acquisition of clinical data as presented in this study.

Sentinel-node biopsy in apparent early stage ovarian cancer: final results of a prospective multicentre study (SELLY)

AIM

To evaluate the sensitivity and specificity of sentinel-lymph-node mapping compared with the gold standard of systematic lymphadenectomy in detecting lymph node metastasis in apparent early stage ovarian cancer.

METHODS

Multicenter, prospective, phase II trial, conducted in seven centers from March 2018 to July 2022. Patients with presumed stage I-II epithelial ovarian cancer planned for surgical staging were eligible. Patients received injection of indocyanine green in the infundibulo-pelvic and, when feasible, utero-ovarian ligaments and sentinel lymph node biopsy followed by pelvic and para-aortic lymphadenectomy was performed. Histopathological examination of all nodes was performed including ultra-staging protocol for the sentinel lymph node.

RESULTS

174 patients were enrolled and 169 (97.1 %) received study interventions. 99 (58.6 %) patients had successful mapping of at least one sentinel lymph node and 15 (15.1 %) of them had positive nodes. Of these, 11 of 15 (73.3 %) had a correct identification of the disease in the sentinel lymph node; 7 of 11 (63.6 %) required ultra-staging protocol to detect nodal metastasis. Four (26.7 %) patients with node-positive disease had a negative sentinel-lymph-node (sensitivity 73.3 % and specificity 100.0 %).

CONCLUSIONS

In a multicenter setting, identifying sentinel-lymph nodes in apparent early stage epithelial ovarian cancer did not reach the expected sensitivity: 1 of 4 patients might have metastatic lymphatic disease unrecognized by sentinel-lymph-node biopsy. Nevertheless, 35.0 % of node positive patients was identified only thanks to ultra-staging protocol on sentinel-lymph-nodes.

pSTAT5 is associated with improved survival in patients with thick or ulcerated primary cutaneous melanoma

Identifying prognostic biomarkers to predict clinical outcomes in stage I and II cutaneous melanomas could guide the clinical application of adjuvant and neoadjuvant therapies. We aimed to investigate the prognostic value of phosphorylated signal transducer and activator of transcription 5 (pSTAT5) as a biomarker in early-stage melanoma. This study evaluated all initially staged Ib and II melanoma patients undergoing sentinel node biopsy at a tertiary centre in Brisbane, Australia between 1994 and 2007, with survival data collected from the Queensland Cancer Registry. Primary melanoma tissue from 189 patients was analysed for pSTAT5 level through immunohistochemistry. Cox regression modelling, with adjustment for sex, age, ulceration, anatomical location, and Breslow depth, was applied to determine the association between pSTAT5 detection and melanoma-specific survival. Median duration of follow-up was 7.4 years. High pSTAT5 detection was associated with ulceration and increased tumour thickness. However, multivariate analysis indicated that high pSTAT5 detection was associated with improved melanoma-specific survival (hazard ratio: 0.15, 95% confidence interval: 0.03-0.67) as compared to low pSTAT5 detection. This association persisted when pSTAT5 detection was limited to immune infiltrate or the vasculature, as well as when sentinel node positivity was accounted for. In this cohort, staining for high-pSTAT5 tumours identified a subset of melanoma patients with increased survival outcomes as compared to low-pSTAT5 tumours, despite the former having higher-risk clinicopathological characteristics at diagnosis. pSTAT5 is likely an indicator of local immune activation, and its detection could represent a useful tool to stratify the risk of melanoma progression.

Hot dots - which nodes should be removed in sentinel lymph node biopsy for melanoma?

BACKGROUND

Sentinel lymph node biopsy (SLNB) is a critical staging tool for melanoma patients. The optimal number of lymph nodes removed in SLNB remains unclear. In this study, we retrospectively analysed and tested different criteria for selecting sentinel lymph nodes (SLNs) by radiotracer uptake and blue dye, and their impact on nodal staging. We also evaluated the association between SLN tumour burden and radiotracer uptake.

METHODS

The study population consisted of melanoma patients undergoing SLNB. During the operation all radioactive and blue nodes were removed and sent for histopathological analysis. The ex vivo radioactive count and presence of blue dye of each node were recorded, and these were correlated with presence and size of metastasis in each SLN.

RESULTS

Altogether 175 patients with clinically occult metastasis presented with one or more positive, i.e. metastatic, SLNs. The mean number of lymph nodes removed was 4.5, and the mean number of positive lymph nodes was 1.5 per patient. The most radioactive or hottest node was negative in 38 patients (22%). By removing the hottest node and all nodes with radioactivity >10% of the hottest node, 97% of patients would have been staged correctly. In five patients, metastasis was found solely in a SLN with radioactivity <10% of the hottest node. Of all 267 positive nodes removed, 125 (47%) contained blue dye. Patients with a negative hottest node were associated with lower SLN tumour burden.

CONCLUSIONS

By removing the hottest node and all nodes with radioactivity >10% of the hottest node, 97% of patients with SLN metastases are correctly staged with or without using blue dye.

Invasive Cutaneous Melanoma: Evaluating the Prognostic Significance of Some Parameters Associated with Lymph Node Metastases

Background and Objectives: This study aimed to assess the clinical-pathological profile of patients with invasive cutaneous melanomas and to identify the parameters with a prognostic role in the lymph nodal spread of this malignant tumor. Materials and Methods: We performed a retrospective study on patients with invasive cutaneous melanomas who underwent surgery in the "Pius Brînzeu" County Clinical Emergency Hospital from Timișoara, Romania, and were evaluated for the status of loco-regional lymph nodes. We selected and analyzed some parameters searching for their relationship with lymph node metastases. Results: We identified 79 patients with invasive cutaneous melanomas (29 men and 50 women, mean age 59.36 years). A percentage of 58.3% of melanomas had Breslow tumor thickness >2 mm; 69.6% of melanomas showed a Clark level IV-V. Tumor ulceration was present in 59.5% of melanomas. A mitotic rate of ≥5 mitoses/mm² was observed in 48.1% of melanomas. Tumor-infiltrating lymphocytes (TILs), non-brisk, were present in 59.5% of cases and 22.8% of patients had satellite/in-transit metastasis (SINTM). Tumor regression was identified in 44.3% of cases. Lymph nodes metastases were found in 43.1% of patients. Statistical analysis showed that lymph node metastases were more frequent in melanomas with Breslow thickness >2 mm (p = 0.0002), high Clark level (p = 0.0026), mitotic rate >5 mitoses/mm² (p = 0.0044), ulceration (p = 0.0107), lymphovascular invasion (p = 0.0182), SINTM (p = 0.0302), and non-brisk TILs (p = 0.0302). Conclusions: The Breslow thickness >2 mm, high Clark level, high mitotic rate and ulceration are the most important prognostic factors for lymph nodal spread in cutaneous melanomas. However, some melanomas without these clinical-pathological features can have an unexpected, aggressive evolution, which entails the necessity of close and prolonged clinical follow-up of patients, including those with lesions considered without risk.

A Clinical Decision Tool to Calculate Pretest Probability of Sentinel Lymph Node Metastasis in Primary Cutaneous Melanoma

BACKGROUND

Although sentinel lymph node biopsy (SLNB) status is a strong prognostic indicator for cutaneous melanoma, unnecessary SLNBs have substantial cost and morbidity burden.

OBJECTIVE

This study was designed to develop, validate, and present a personalized, clinical, decision-making tool using nationally representative data with clinically actionable probability thresholds (Expected Lymphatic Metastasis Outcome [ELMO]).

METHODS

Data from the Surveillance, Epidemiology, and End Results (SEER) Registry from 2000 to 2017 and the National Cancer Database (NCDB) from 2004 to 2015 were used to develop and internally validate a logistic ridge regression predictive model for SLNB positivity. External validation was done with 1568 patients at a large tertiary referral center.

RESULTS

The development cohort included 134,809 patients, and the internal validation cohort included 38,518 patients. ELMO (AUC 0.85) resulted in a 29.54% SLNB reduction rate and greater sensitivity in predicting SLNB status for T1b, T2a, and T2b tumors than previous models. In external validation, ELMO had an accuracy of 0.7586 and AUC of 0.7218. Limitations of this study are potential miscoding, unaccounted confounders, and effect modification.

CONCLUSIONS

ELMO ( https://melanoma-sentinel.herokuapp.com/ ) has been developed and validated (internally and externally) by using the largest publicly available dataset of melanoma patients and was found to have high accuracy compared with other published models and gene expression tests. Individualized risk estimates for SLNB positivity are critical in facilitating thorough decision-making for healthcare providers and patients with melanoma.

The Value of Contrast-Enhanced Ultrasound in the Detection of Sentinel Lymph Nodes in Malignant Melanoma

OBJECTIVE

To evaluate the location and characterization value of contrast-enhanced ultrasound (CEUS) in the detection of sentinel lymph nodes (SLNs) in malignant melanoma.

METHODS

SLNs and the lymph node network were tracked by subcutaneous injection of ultrasonic contrast agent around the tumor and preoperative localization, and qualitative analyses were performed. The SLNs were also detected by the intraoperative subcutaneous injection of carbon nanoparticles, and the findings were compared with lymph nodes located by CEUS. The accuracy of the preoperative lymph node identification was evaluated by the results of postoperative pathology, which served as the gold standard of detection.

RESULTS

In 47 patients with malignant melanoma, the mean number of SLNs detected by CEUS was 1.72 ± 0.10, while that by carbon nanoparticle administration it was 1.79 ± 1.07 (P = .371 > .05). Seven cases of lymph node metastasis were detected by CEUS, with a sensitivity of 70.0%, specificity of 97.3%, positive predictive value of 87.5%, negative predictive value of 92.3%, and accuracy of 91.5%. There was high consistency between the findings of CEUS and pathology in differentiating benign and malignant lymph nodes (kappa = 0.726, χ²  = 25.243, P < .001).

CONCLUSIONS

CEUS can localize and differentiate SLNs in malignant melanoma, and thus, may potentially guide clinical treatment in the future.

New Zealand patients have a higher melanoma burden in sentinel nodes and completion lymphadenectomy than patients in MSLT-II

New Zealand has the highest rate of melanoma-related mortality in the world. Access to immunotherapy and radiology is limited and surgical treatment of regional disease remains important. A recent pilot study of a single health district observed a higher nodal melanoma burden than was reported in the second Multicentre Selective Lymphadenectomy Trial (MSLT-II). In this study, a series of regional censuses were undertaken covering the 10 years immediately prior to the publication of MSLT-II. The study population was seven District Health Boards covering 62.2% of the population of New Zealand across a 10-year period preceding MSLT-II. The primary outcomes measured were the size of sentinel lymph node metastases and non-sentinel node (NSN) positivity on completion lymph node dissection (CLND) for patients with a positive sentinel lymph node biopsy (SLNB). In the 2323 SLNB identified, the mean sentinel lymph node metastatic deposit size was larger compared to MSLT-II (2.55 vs. 1.07/1.11 mm). A greater proportion of New Zealand patients (44.2%) had metastatic deposits larger than 1 mm compared to MSLT-II (33.2/34.5%) and the rate of non-sentinel node involvement on CLND was also higher (22.2% vs. 11.5%). These findings indicate that New Zealand is a high-risk population for nodal melanoma metastases. Due to these differences, the conclusions of MSLT-II may not be able to be applied to melanoma patients in the 7 regions studied in New Zealand.

The Association of Guideline-Concordant Sentinel Lymph Node Biopsy for Melanoma at Minority-Serving Hospitals

BACKGROUND

Minority-serving hospitals (MSHs) have been associated with lower guideline adherence and worse outcomes for various cancers. However, the relationship among MSH status, concordance with sentinel lymph node biopsy (SLNB) guidelines, and overall survival (OS) for patients with cutaneous melanoma is not well studied.

METHODS

The National Cancer Database was queried for patients diagnosed with T1a*, T2, and T3 melanoma between 2012 and 2017. MSHs were defined as the top decile of institutions ranked by the proportion of minorities treated for melanoma. Based on National Comprehensive Cancer Network guidelines, guideline-concordant care (GCC) was defined as not undergoing SLNB if thickness was < 0.76 mm without ulceration, mitosis ≥ 1/mm², or lymphovascular invasion (T1a*), and performing SLNB for patients with intermediate thickness melanomas between 1.0 and 4.0 mm (T2/T3). Multivariable logistic regressions examined associations with GCC. The Kaplan-Meier method and log-rank tests were used to evaluate OS between MSH and non-MSH facilities.

RESULTS

Overall, 5.9% (N = 2182/36,934) of the overall cohort and 37.8% of minorities (n = 199/527) were managed at MSHs. GCC rates were 89.5% (n = 33,065/36,934) in the overall cohort and 85.4% (n = 450/527) in the minority subgroup. Patients in the overall cohort (odds ratio [OR] 0.85; p = 0.02) and the minority subgroup (OR 0.55; p = 0.02) were less likely to obtain GCC if they received their care at MSHs compared with non-MSHs. Minority patients receiving care at MSHs had a decreased survival compared with those treated at non-MSHs (p = 0.002).

CONCLUSIONS

Adherence to SLNB guidelines for melanoma was lower at MSHs. Continued focus is needed on equity in melanoma care for minority patients in the United States.

The Evolution of the Sentinel Node Biopsy in Melanoma

The growing repertoire of approved immune-checkpoint inhibitors and targeted therapy has revolutionized the adjuvant treatment of melanoma. While the treatment of primary cutaneous melanoma remains wide local excision (WLE), the management of regional lymph nodes continues to evolve in light of practice-changing clinical trials and dramatically improved adjuvant therapy. With large multicenter studies reporting no benefit in overall survival for completion lymph node dissection (CLND) after a positive sentinel node biopsy (SLNB), controversy remains regarding patient selection and clinical decision-making. This review explores the evolution of the SLNB in cutaneous melanoma in the context of a rapidly changing adjuvant treatment landscape, summarizing the key clinical trials which shaped current practice guidelines.

Impact of second histopathological review of melanocytic skin lesions at a melanoma reference center in Brazil

BACKGROUND

After the biopsy of a suspicious melanocytic lesion, patients depend on the pathologist's precision of specimen evaluation.

METHODS

We assessed the agreement between histopathological reports made by general pathologists and reviewed by a dermatopathologist to evaluate the impact on the patient's management.

RESULTS

In 79 cases analyzed, underdiagnosis was observed in 21.6% and overdiagnosis in 17.7%, resulting in changes in the patients' conduct. The assessment of the Clark level, ulceration and histological type showed mild agreement (P<0.001); the Breslow thickness, surgical margin, and staging showed moderate agreement (P<0.001).

CONCLUSIONS

A dermatopathologist's review should be incorporated into the routine of reference services for pigmented lesions.

Multicenter Adoption and Outcomes of Nodal Observation for Patients with Melanoma and Sentinel Lymph Node Metastases

BACKGROUND

Following publication of the MSLT-II trial showing no survival benefit of completion lymphadenectomy (CLND) in patients with melanoma sentinel lymph node (SLN) metastases, it is expected that practice patterns have changed. The purpose of this study is to understand real-world practices and outcomes after publication of this landmark trial.

PATIENTS AND METHODS

Patients with truncal/extremity melanoma SLN metastases diagnosed between 2013 and 2019 at four academic cancer centers were included in this retrospective cohort study. Descriptive statistics, Cox proportional hazards model, and multivariable regression were used to characterize the cohort and identify predictors of CLND, harboring non-SLN (NSLN) metastases, and survival.

RESULTS

Results of 1176 patients undergoing SLN biopsy, 183 had SLN metastases. The number of patients who underwent CLND before versus after trial publication was 75.7.% versus 20.5% (HR 0.16, 95% CI 0.09-0.28). Of those undergoing nodal observation (NO), 92% had a first nodal-basin ultrasound, while 63% of patients had a fourth. In exploratory multivariable analyses, age ≥ 50 years was associated with lower rate of CLND (HR 0.58, 95% CI 0.36-0.92) and larger SLN deposit (> 1.0 mm) with increased rate of CLND (HR 1.87, 95% CI 1.17-3.00) in the complete cohort. Extracapsular extension was associated with increased risk of NSLN metastases (HR 12.43, 95% CI 2.48-62.31). Adjusted survival analysis demonstrated no difference in recurrence or mortality between patients treated with CLND versus NO at median 2.2-year follow-up.

CONCLUSION

Nodal observation was rapidly adopted into practice in patients with melanoma SLN metastases at four centers in Canada. Younger age and higher nodal burden were associated with increased use of CLND after trial publication. Ultrasound (US) surveillance decreased with time from SLNB. In our study, CLND was not associated with a decreased risk of recurrence or mortality.

Predictive accuracy of elevated mitotic rate on lymph node positivity and recurrence in thin melanomas

Background

Mitotic rate (MR) is considered an important prognostic factor for melanoma but is not currently used for staging because its nuanced effect is not yet well-delineated. We sought to determine if T category-specific MR is predictive of sentinel lymph node (SLN) positivity, recurrence, and melanoma-specific mortality (MSM).

Methods

A retrospective review of patients with primary cutaneous melanoma from 1994 to 2020 at a single academic center was performed. Patient demographics and tumor characteristics were recorded. MR was considered elevated for each AJCC8-defined T category if it was ≥2 mitoses/mm² for T1, ≥4 mitoses/mm² for T2, ≥6 mitoses/mm² for T3, or ≥7 mitoses/mm² for T4. Statistical analysis was performed to assess the predictive accuracy of MR on selected outcomes while controlling for ulceration.

Results

Data from 2,984 patients with complete records were analyzed. Along with Breslow thickness and ulceration, elevated MR was associated with higher risk of MSM (HR 1.816, P=0.0001). There was no difference among patients with ulcerated T1 or T2 tumors regardless of MR, but those with non-ulcerated T1 or T2 tumors and elevated MR were more likely to have positive SLNs (P<0.0001 and P=0.0043, respectively) and recurrence (P=0.0007 and P=0.0004, respectively) compared to counterparts with low MR. There were no notable differences for T3 or T4 tumors based on MR.

Conclusions

Elevated MR is associated with SLN positivity and recurrence in thin melanomas, independent of ulceration. SLN biopsy should therefore be strongly considered for patients with non-ulcerated lesions <0.8 mm thick if the MR is ≥2 mitoses/mm².

Regional control after precision lymph node dissection for clinically evident melanoma metastasis

INTRODUCTION

Completion lymph node dissection (CLND) for microscopic lymph node metastases has been replaced by observation; however, CLND is standard for clinically detectable nodal metastases (cLN). CLND has high morbidity, which may be reduced by excision of only the cLN (precision lymph node dissection [PLND]). We hypothesized that same-basin recurrence risk would be low after PLND.

METHODS

Retrospective review at four tertiary care hospitals identified patients who underwent PLND. The primary outcome was 3-year cumulative incidence of isolated same-basin recurrence.

RESULTS

Twenty-one patients underwent PLND for cLN without synchronous distant metastases. Reasons for forgoing CLND included patient preference (n = 11), comorbidities (n = 5), imaging indeterminate for distant metastases (n = 2), partial response to checkpoint blockade (n = 1), or not reported (n = 2). A median of 2 nodes (range: 1-6) were resected at PLND, and 68% contained melanoma. Recurrence was observed in 33% overall. Only 1 patient (5%) developed an isolated same-basin recurrence. Cumulative incidences at 3 years were 5.0%, 17.3%, and 49.7% for isolated same-basin recurrence, any same-basin recurrence, and any recurrence, respectively. Complications from PLND were reported in 1 patient (5%).

CONCLUSIONS

These pilot data suggest that PLND may provide adequate regional disease control with less morbidity than CLND. These data justify prospective evaluation of PLND in select patients.

Subcostal lymph nodes: An unusual sentinel lymph node basin in cutaneous melanoma

BACKGROUND AND OBJECTIVES

Lymphatic drainage from subcostal nodes, along the costal groove, have not previously been characterized as sites for melanoma drainage and metastasis. This study reports a series of patients with subcostal nodes draining primary melanomas, with characterization of the sites of primary melanomas that drain to these nodes.

METHODS

Patients who presented to our institution between 2005 and 2020 with documented cutaneous melanoma and sentinel lymph node biopsy of a subcostal node (sentinel = S), or metastases to subcostal nodes later in clinical management (recurrent = R) were included. Patient demographics, melanoma pathology, nodal features, imaging information, surgical approaches, and outcomes data were collected.

RESULTS

Six patients had subcostal sentinel nodes (SNs). Primary sites included the posterior trunk and lateral chest wall. Subcostal nodes were found under ribs 10-12. Subcostal SNs had at least one dimension measuring 3 mm or less. There were no surgical complications related to removing the subcostal SN.

CONCLUSIONS

Melanoma can metastasize to subcostal lymph nodes and be found at the time of SN biopsy or identified at recurrence. These small nodes are fed by lymphatic channels that run in the neurovascular bundle under the ribs. When lymphatic mapping identifies a subcostal SN, it should be excised.

Suction Drain Volume following Axillary Lymph Node Dissection for Melanoma-When to Remove Drains? A Retrospective Cohort Study

Postoperative complications such as seroma formation and wound-site infection occur following completion axillary lymph node dissection (ALND) for melanoma. We analyzed the impact of time-to-drain removal and drainage volume on seroma formation after ALND. We retrospectively analyzed data from 118 patients after completion ALND for melanoma. Primary endpoints were daily amount of drainage volume, seroma formation and time-to-drain removal. Secondary endpoints included patient-related, disease-specific and perioperative parameters as well as the number of histologically analyzed lymph nodes and surgical complications graded by the Clavien−Dindo classification (CDCL). Statistical analyses were performed using logistic regression models. Drain removal around the 8th postoperative day was statistically associated with a lower risk for the occurrence of seroma formation (p < 0.001). Patients with an increased drainage volume during the early postoperative days were more prone to develop seroma after drain removal. With 49% (CDCL I and II), most complications were managed conservatively, while only 5.9% (CDCL III) required revision surgery (CDCL overall: 55.9%). ALND is a safe procedure with a low rate of severe CDCL III type of complications. To decrease seroma evacuation, our results imply that drains should be removed around the 8th postoperative day to reduce the risk of infection, readmission or prolonged hospitalization.

Intermediate-thickness melanoma: A population-based study of surgical quality metrics

BACKGROUND

Variability in guideline compliance for melanoma lymph node surgery is partially attributable to controversy about patient selection. Prior data has indicated suboptimal practice of sentinel lymph node biopsy and undertreatment of clinically node-positive disease, predating Multicenter Selective Lymphadenectomy Trial II publication. To minimize bias, we studied compliance with lymph node surgery guidelines in T2/T3 (intermediate-thickness) melanoma patients, where the greatest agreement exists.

METHODS

T2/T3 and metastasis 0 melanoma cases were identified from 2004 to 2018 Surveillance, Epidemiology, and End Results data. Analysis used Cochran-Armitage test for trends, multivariable logistic regression, and Kaplan-Meier survival estimates.

RESULTS

Of 66,319 eligible T2/T3 patients, 57,211 were clinically node negative; 2,191 were clinically node positive; 6,197 were clinical node unreported; and 19,044/66,319 (28.8%) had no lymph node surgery. Among clinically node-negative patients, 36,433 (63.7%) underwent sentinel lymph node biopsy and 31,026 (85.2%) were pathologically node negative; 1,499 clinically node-positive patients (68.4%) had a lymph node dissection. Lymph node dissection rates declined from 2004 to 2018, 79.8% to 32.0% for clinically node-negative/pathologically node-positive patients and 80.4% to 61.2% for clinically node-positive/pathologically node-positive patients (both P < .0001). For clinically node-negative patients, lymph node surgery compliance improved from 63.7% (2004) to 70.4% (2018) (P < .0001). Compliance correlated with younger age, male sex, tumor mitotic rate, and site (extremity > trunk/head/neck) in multivariable analysis and improved 5-year cancer-specific survival (90.0% vs 83.4%) (all P < .0001).

CONCLUSIONS

Despite clear guidelines, one-third of intermediate-thickness melanoma patients in a recent cohort did not have recommended lymph node surgery. Lymph node status is a key determinant of the relative benefit of adjuvant systemic therapy and the need for active surveillance of pathologically node-positive/clinically node-negative patients. These data highlighted a clinical care gap. Efforts to improve guideline compliance are a logical strategy to improve cancer outcomes for intermediate-thickness melanoma patients.

Current and future approaches in the surgical management of T3b/T4 primary and locoregionally advanced melanoma

Currently accepted principles of surgical management-margin width, use of sentinel node biopsy, performance of radical node dissections for node-positive cases-and some aspects of postoperative management (use of radiation for desmoplastic melanoma primaries and for clinically node-positive disease) will change in the future with the potential widespread adoption of adjuvant and neoadjuvant therapies.

National Practice Patterns in the Management of the Regional Lymph Node Basin After Positive Sentinel Lymph Node Biopsy for Cutaneous Melanoma

BACKGROUND

Immediate completion lymph node dissection (CLND) for patients with sentinel lymph node (SLN) metastasis from cutaneous melanoma has been replaced largely by ultrasound nodal surveillance since the publication of two landmark trials in 2016 and 2017. National practice patterns of CLND remain poorly characterized.

METHODS

Patients with a diagnosis of cutaneous melanoma in 2016 and 2018 without clinical nodal disease who underwent sentinel lymph node biopsy (SLNB) were identified from the National Cancer Database (NCDB). Characteristics associated with CLND were analyzed by uni- and multivariate logistic regression. Overall survival (OS) was estimated using Kaplan-Meier and Cox proportional hazards regression analyses.

RESULTS

Of the 3517 patients included in the study, 1405 had disease diagnosed in 2016. The patients with cutaneous melanoma diagnosed in 2016 had a median age of 60 years and a tumor thickness of 2.3 mm compared to 62 years and 2.4 mm, respectively, for the patients with cutaneous melanoma diagnosed in 2018. According to the NCDB, 40 % (n = 559) of the patients underwent CLND in 2016 compared with 6 % (n = 132) in 2018. The factors associated with receipt of CLND in 2018 included younger age (odds ratio [OR], 0.97; 95 % confidence interval [CI], 0.95-0.99; p = 0.001), rural residence (OR, 3.96; 95 % CI, 1.50-10.49; p = 0.006), head/neck tumor location (OR, 1.88; 95 % CI, 1.10-3.23; p = 0.021), and more than one positive SLN (OR, 1.80; 95 % CI, 1.17-2.76; p = 0.007). The 5-year OS did not differ between the patients who received SLNB only and those who underwent CLND (hazard ratio [HR], 0.93; p = 0.54).

CONCLUSION

The rates of CLND have decreased nationally. However, patients with head/neck primary tumors who live in rural locations are more likely to undergo CLND, highlighting populations for which treatment may be non-uniform with national practice patterns.

Effect of the time interval between melanoma diagnosis and sentinel node biopsy on the size of metastatic tumour deposits in node-positive patients

INTRODUCTION

This study sought to assess whether the interval between diagnostic excision-biopsy of a primary melanoma and definitive wide excision with sentinel node biopsy (SNB) influenced the size of SN metastatic deposits, which might have implications for management and prognosis.

METHODS

Data were collected for (i) a Dutch population-based cohort of patients treated between 2004 and 2014 who underwent SNB within 100 days of complete excision of their primary melanoma and who were SN-positive with known SN metastasis diameter (n = 1027) and (ii) a cohort from a large Australian melanoma treatment centre (n = 541) who presented in the same time period. The effects of SNB timing on the size of SN metastatic deposits were analysed.

RESULTS

Dutch patients whose SNB was performed in the second or third months after diagnosis had significantly larger SN metastasis diameters than patients who had their SNB in the first month (median increases of 17% (95%CI -14, 60%, p = 0.211) and 71% (95%CI 15, 119%, p = 0.004), respectively). No significant difference in tumour diameter for early and late SNB was found in the Australian cohort.

CONCLUSIONS

SN metastasis diameter became progressively greater with SN biopsy in the second and third months after primary melanoma diagnosis in the larger, population-based patient cohort. An increase in metastasis diameter was not observed in the smaller, institutional cohort, possibly due to detection of larger SN metastases by routine pre-operative ultrasound, with fine-needle biopsy confirmation. These patients did not proceed to SNB and were therefore not included in the study.

Melanoma sentinel lymph node biopsy and completion lymph node dissection: A regional hospital experience

Completion lymph node dissection (CLND) following positive sentinel lymph node biopsy (SLNB) for cutaneous melanoma is a topic of controversy. The second Multicenter Selective Lymphadenectomy Trial (MSLT-II) suggested no survival benefit with CLND over observation amongst patients with a positive SLNB. The findings of the MSLT-II may have limited applicability to our high-risk population where nodal ultrasound and non-surgical melanoma treatment is rationed. In this regional, retrospective study, we reviewed primary melanoma, SLNB and CLND histopathological reports in the Bay of Plenty District Health Board (BOPDHB) across a 10-year period. The primary outcomes measured were size of sentinel lymph node metastases and non-sentinel node (NSN) positivity on CLND for patients with a positive SLNB. In the 157 SLNB identified, the mean sentinel lymph node metastatic deposit size was larger in BOPDHB compared with MSLT-II (3.53 vs 1.07/1.11mm). A greater proportion of BOPDHB patients (54.8%) had metastatic deposits larger than 1mm compared with MSLT-II (33.2/34.5%) and the rate of NSN involvement on CLND was also higher (23.8% vs 11.5%). These findings indicate that the BOPDHB is a high-risk population for nodal melanoma metastases. Forgoing CLND in the context of a positive SLNB may place these patients at risk.

Is the presence of tumor-infiltrating lymphocytes predictive of outcomes in patients with melanoma?

BACKGROUND

The significance of tumor-infiltrating lymphocytes (TILs) in melanoma is debated. This article presents a multicenter, retrospective study assessing the predictive and prognostic value of TILs.

METHODS

The Sentinel Lymph Node Working Group database was queried from 1993 to 2018 for cases with known TIL data. TILs were categorized as absent or present, which included nonbrisk (NB), brisk (B), and present but unspecified TIL levels. Clinicopathologic factors were correlated with TILs, sentinel lymph node (SLN) status, and melanoma-specific survival (MSS).

RESULTS

Overall, 3203 patients were included. The median thickness was 1.5 mm, and 469 cases had SLN metastases. TILs were present in 2458 cases (76.7%), with NB, B, and unspecified TILs seen in 1691 (68.8%), 691 (28.1%), and 76 (3.1%), respectively. Multivariable analysis showed that the presence of TILs significantly predicted a negative SLN biopsy (P < .05). The median follow-up was 25.2 months. MSS was significantly better for cases with TILs than cases without TILs (P < .001). According to multivariable analysis, age, gender, thickness, mitotic rate, ulceration, lymphovascular invasion, and SLN status were significantly prognostic of MSS (all P values < .05). Although TILs were not prognostic of MSS, when multiple imputation was used and the SLN status was excluded, the presence of TILs was significantly prognostic of improved MSS (hazard ratio, 0.78; 95% confidence interval, 0.64-0.95; P = .0154).

CONCLUSIONS

TILs are a favorable marker because their presence significantly predicts a negative SLN, and the absence of TILs may be a prognostic marker of worse survival in patients with a positive SLN but not a negative SLN. TILs may also serve as a prognostic marker of survival when the SLN status is not considered.

Melanoma trials that defined surgical management: Overview of trials that established NCCN margin guidelines

Since the observation that clearance of all visible and microscopic tumors from cutaneous melanoma is critical to prevent a recurrence, wide surgical margins have been central to surgical dogma. In the last several decades, more conservative margin widths have been vigorously studied by surgical investigators to lessen wound complications, the need for reconstruction, and healthcare costs. This review summarizes surgeon-led clinical trials that define current guidelines and highlights the challenges to initiate and perform trials today.

Validation of a clinicopathological and gene expression profile model to identify patients with cutaneous melanoma where sentinel lymph node biopsy is unnecessary

BACKGROUND

In patients with cutaneous melanoma, sentinel lymph node biopsy (SLNB) serves as an important technique to asses disease stage and to guide adjuvant systemic therapy. A model using clinicopathologic and gene expression variables (CP-GEP; Merlin Assay) has recently been introduced to identify patients that may safely forgo SLNB. Herein we present data from an independent validation cohort of the CP-GEP model in Swedish patients.

METHODS

Archival histological material (primary melanoma tissue) from a prospectively collected cohort of 421 consecutive patients with pT1-T4 melanoma undergoing SLNB between 2006 and 2014 was analyzed using the CP-GEP model. CP-GEP combines Breslow thickness and patient age with the expression levels of eight genes from the primary melanoma. Stratification is based on their risk for nodal metastasis: CP-GEP Low Risk or CP-GEP High Risk.

RESULTS

The SLNB positivity rate was 13%. Of 421 primary melanomas, the CP-GEP model identified 86 patients as having a low risk for nodal metastasis. In patients with pT1-2 melanomas, the SLNB reduction rate was 35.4% (95% CI: 29.4-41.8) with a negative predictive value (NPV) of 96.5% (95% CI: 90.0-99.3). Among patients with pT1-3 melanomas, CP-GEP suggested a SLNB reduction rate of 24.0% (95% CI: 19.7-28.8) and a NPV of 96.5% (95% CI: 90.1-99.3). Only one of 118 pT3 tumors was classified as CP-GEP Low Risk, and all pT4 tumors were classified as being high risk for nodal metastasis.

CONCLUSION

This study demonstrates that CP-GEP can identify patients with a low risk for nodal metastasis. Patients with pT1-2 melanomas have the highest clinical benefit from using the test, where 35% of the patients could forgo a SLNB procedure.

RIPK3 and AXL Expression Study in Primary Cutaneous Melanoma Unmasks AXL as Predictor of Sentinel Node Metastasis: A Pilot Study

Malignant melanoma (MM) is the most lethal skin cancer. AXL is a tyrosine kinase receptor involved in several oncogenic processes and might play a role in blocking necroptosis (a regulated cell death mechanism) in MM through the downregulation of the necroptotic-related driver RIPK3. The aim of this study was to evaluate the clinical impact of the expression of AXL and RIPK3 in 108 primary cutaneous MMs. Association between AXL and RIPK3 immunoreactivity and clinical-pathological variables, sentinel lymph node status, and tumor-infiltrating lymphocytes (TILs) was assessed. Immunoreaction in tumor cells was detected in 30 cases (28%; range, 5%-80%) and in 17 cases (16%; range, 5%-50%) for AXL and RIPK3, respectively. Metastases in the sentinel lymph nodes were detected in 14 out of 61 patients, and these were associated with AXL-positive immunoreactivity in the primary tumor (p < 0.0001). No association between AXL and TILs was found. RIPK3 immunoreactivity was not associated with any variables. A final logistic regression analysis showed Breslow and AXL-positive immunoreactivity as the stronger predictor for positive sentinel node status [area under the receiver operating characteristic curve (AUC) of 0.96]. AXL could be a potential new biomarker for MM risk assessment, and it deserves to be further investigated in larger studies.

Pelvic sentinel lymph nodes have minimal impact on survival in melanoma patients

Background

Lower limb or trunk melanoma often presents with femoral and pelvic sentinel lymph nodes (SLNs). The benefits of harvesting pelvic lymph nodes remain controversial. In this retrospective study, the frequency and predictors of pelvic SLNs (PSLNs), and the impact of PSLNs on survival and staging was investigated.

Methods

Altogether 285 patients with cutaneous melanoma located in the lower limb or trunk underwent sentinel lymph node biopsy of the inguinal/iliac lymph node basin at Helsinki University Hospital from 2009–2013. Patient characteristics, detailed pathology reports and follow-up data were retrieved from hospital files. Subgroups of patients categorized by presence of PSLNs were compared for outcome parameters including progression-free survival, melanoma-specific survival and groin recurrence.

Results

Superficial femoral/inguinal SLNs were present in all patients and 199 (69.8 per cent) also had PSLNs removed. Median number of SLNs per patient was five and median number of PSLNs was two. Sixty-three patients (22.1 per cent) had metastases in their SLNs and seven (2.5 per cent) had metastases in PSLNs. A single patient had metastases solely in PSLNs, while superficial SLNs remained negative. Harvesting PSLNs or the number of PSLNs retrieved had no impact on progression-free survival or overall survival. The removal of PSLNs did not affect the risk of postoperative seroma or lymphoedema. The only predictor of positive PSLNs was radioactivity count equal to or more than that of the hottest superficial SLNs.

Conclusion

Pelvic SLNs have minimal clinical impact on the outcome of melanoma patients especially in cases with negative superficial femoral/inguinal SLNs. Removal of PSLNs should be considered when they are the most radioactive nodes or equal to the hottest superficial femoral/inguinal SLNs in lymphoscintigraphy or during surgery.

Preliminary results were presented in part at the International Sentinel Node Society Biennial Meeting, Tokyo, Japan, 11–13 October 2018.

Randomized Study of Wound Drainage on Early Complications After Lymph Node Dissection for Melanoma

INTRODUCTION

The complication rate after axillary lymph node dissection (ALND) and inguinal lymph node dissection (ILND) in melanoma patients is high. The aim of this randomized non-inferiority study was to evaluate the effect of postoperative wound drainage on early complications after ALND and ILND.

MATERIALS AND METHODS

Between 2018 and 2020, 104 stage III melanoma patients operated on with ALND or ILND were randomized to a study group with complete wound drain removal 3 wk after surgery or a control group with progressive drain removal. The primary end point was overall early complications graded according to the modified Clavien-Dindo classification. Secondary endpoints were length of hospital stay and prognostic factors for early complications.

RESULTS

Of the 99 patients analyzed, ALND was performed in 58 patients and ILND in 41 patients. Overall, 62 patients (62.6%) developed early complications: 30 in the study group and 32 in the control group (P = 0.53). The confidence interval for the difference in proportions of patients without early complications in the two groups was -0.27 to 0.11 (P = 0.42), hence non-inferiority could be claimed. Length of hospital stay was 5 d in the study group compared to 6 in the control group (P < 0.01). ILND was associated with increased risk of early complications compared to ALND (75.6% versus 53.4%, P = 0.04).

CONCLUSIONS

Complete drain removal 3 wk after ALN and ILND in stage III melanoma patients did not increase the risk of early complications compared to progressive drain removal.

More sentinel lymph node biopsies for thin melanomas after transition to AJCC 8th edition do not increase positivity rate: A Danish population-based study of 7148 patients

BACKGROUND

We evaluated the outcome of sentinel lymph node biopsies (SLNB) in patients with thin melanoma before and after the implementation of AJCC 8th edition (AJCC8) and identified predictors of positive sentinel lymph nodes (+SLN).

METHODS

Patients diagnosed with T1 melanomas (Breslow thickness ≤1 mm) during 2016-2017 as per AJCC 7th edition (AJCC7) (n = 3414) and 2018-2019 as per AJCC8 (n = 3734) were identified in the Danish Melanoma Database.

RESULTS

More SLNBs were performed in the AJCC8 cohort compared to the AJCC7 (22.2% vs. 16.2%, p < 0.001), with no significant difference in +SLN rates (4.7% vs. 6.7%, p = 0.118). In the AJCC7 + SLN subgroup, no melanomas were ulcerated, 94.6% had mitotic rate (MR) ≥ 1, 67.6% were ≥0.8 mm and 32.4% would be T1a according to AJCC8. In the AJCC8 + SLN subgroup, 10.3% were ulcerated, 74.4% had MR≥ 1, 97.4% were ≥0.8 mm and 23.1% would be T1a according to AJCC7. On multivariable analysis younger age and MR ≥ 1 were significant predictors of +SLN.

CONCLUSION

More SLNBs were performed in T1 melanomas after transition to AJCC8 without an increase in +SLN rate. None of the AJCC8 T1b criteria were significant predictors of +SLN. We suggest that mitosis and younger age should be considered as indications for SLNB in thin melanoma.

Comparison of upper extremity lymphedema after sentinel lymph node biopsy and axillary lymph node dissection: patient-reported outcomes in 3044 patients

PURPOSE

A limited number of studies have examined the impact of type of axillary lymph node surgery on breast cancer-related lymphedema (BCRL) from the patient's perspective. The objective of this study was to assess the impact of sentinel lymph node dissection (SLND) and axillary lymph node dissection (ALND) on the health-related quality of life (HRQOL) in women diagnosed with BCRL using a condition specific patient-reported outcome measure (PROM), the LYMPH-Q upper extremity (UE) module.

METHODS

Adult women diagnosed with BCRL were identified from the Danish National Health Data Authority database for the period 2008 to 2020 and were sent an online REDCap survey with the LYMPH-Q UE module. Information pertaining to axillary surgery was obtained from an online pathology repository. Multivariable linear regression was used to examine differences in the SLND and ALND groups on the LYMPH-Q UE scale scores.

RESULTS

Three thousand and fourty four women with BCRL were included in the analysis. The mean follow-up duration was 8.6 ± 5.15 years (range, 0-36 years). The majority of participants underwent ALND (n = 2805, 92.1%) and only 7.9% (n = 239) received SLND. The mean number of lymph nodes removed in the SLND group was 2.2 ± 1.4. No statistically significant difference was found in the two groups on the LYMPH-Q UE scale scores.

CONCLUSION

There is no difference in women with upper extremity lymphedema after SLND or ALND on the LYMPH-Q UE module scales measuring arm symptoms, function, distress, and appearance.

Integrating 31-Gene Expression Profiling With Clinicopathologic Features to Optimize Cutaneous Melanoma Sentinel Lymph Node Metastasis Prediction

National guidelines recommend sentinel lymph node biopsy (SLNB) be offered to patients with > 10% likelihood of sentinel lymph node (SLN) positivity. On the other hand, guidelines do not recommend SLNB for patients with T1a tumors without high-risk features who have < 5% likelihood of a positive SLN. However, the decision to perform SLNB is less certain for patients with higher-risk T1 melanomas in which a positive node is expected 5%-10% of the time. We hypothesized that integrating clinicopathologic features with the 31-gene expression profile (31-GEP) score using advanced artificial intelligence techniques would provide more precise SLN risk prediction.

Repeat injection following sentinel node nonvisualization on lymphoscintigraphy images can decrease axillary dissection rate in breast cancer patients

AIM

Sentinel node biopsy is considered the standard of care in early-stage breast cancer patients. In the current study, we evaluated the effect of radiotracer reinjection in the case of sentinel node nonvisualization on preoperative lymphoscintigraphy.

MATERIALS AND METHODS

Between March 2017 and March 2020, 1850 early-stage breast cancer patients were referred for sentinel node mapping. All patients received a single injected activity of Tc-99m Phytate intradermally in the periareolar area of the index lesion using an insulin syringe. Lymphoscintigraphy images of the patients were done 1-2 h postinjection. Between March 2017 and September 2017, sentinel node nonvisualization was reported to the surgeon, and for the rest of the study period, the patients received another injected activity of the radiotracer, and immediately, other lymphoscintigraphy images were taken (with the same parameters).

RESULTS

A total of 255 patients entered our study. Fifty-five patients were in group I without any reinjection. The remainder of the patients were in group II. In 155 out of 200 patients of group II, a sentinel node could be visualized following reinjection of the radiotracer. The detection rate was 15 out of 45 and 15 out of 55 in group I and patients without sentinel node visualization even after reinjection, respectively. Axilla was involved in 5 out of 40 (12.5%) patients in group I with intraoperative sentinel node mapping failure. On the other hand, axilla was involved in 27 out of 30 (90%) group II patients with sentinel node nonvisualization.

CONCLUSION

Reinjection of the tracer in cases of no sentinel node visualization in lymphoscintigraphy for breast cancer increases the detection rate of sentinel nodes, and therefore a high number of unnecessary axillary lymph node dissections can be avoided.

Age and Melanocytic Lesions

Age plays a dynamic role in incidence, presentation, and extent of disease for cutaneous melanoma. Even within the spectrum of juvenile melanoma, there exists a range of spitzoid and nonspitzoid melanocytic and melanoma lesions. Spitzoid melanomas, a more favorable disease in juvenile patients, are malignant lesions and require treatment as such. Lymph node metastases in melanoma occur at lower rates in older patients compared with younger counterparts, yet the rate of metastases is still high. Age appears to play an important role in the development and progression of melanoma, and understanding the differences across age populations is important when counseling patients.

Exploratory analysis of lateral pelvic sentinel lymph node status for optimal management of laparoscopic lateral lymph node dissection in advanced lower rectal cancer without suspected lateral lymph node metastasis

Background

Total mesorectal excision (TME) and lateral lymph node dissection (LLND) without radiotherapy (RT) are standard treatment for lower cT3/4 rectal cancers in Eastern countries. In comparative studies, both TME + LLND and RT + TME yield good local control. Although Japanese guidelines recommend LLND for locally advanced rectal cancers below the peritoneal reflection, LLND dissection of clinically negative lateral pelvic lymph nodes (LPLN) is controversial, and laparoscopic TME + LLND is technically challenging and time-consuming. New optical instruments for laparoscopy allow easy perioperative sentinel lymph node (SLN) identification using ICG. The SLN concept may facilitate accurate diagnosis of LPLN involvement, and thus reduce LLND in laparoscopic rectal cancer surgery. Here we investigated lateral pelvic SLN navigation surgery for SLN detection during laparoscopic rectal cancer surgery.

Methods

This study included 21 patients with clinical StageII/III lower rectal cancer without LPLN enlargement, who underwent curative laparoscopic surgery. All patients underwent TME, followed by lateral SLN identification and biopsy using ICG, and then laparoscopic LLND. ICG fluorescence imaging was conducted using the laparoscopic near-infrared camera system.

Results

Lateral SLNs were successfully identified in 16 (76.2%) of the 21 patients. Among the 15 patients without SLN tumor metastasis, the dissected lateral non-SLNs were all negative.

Conclusions

A lack of metastasis in the lateral pelvic SLN seems to reflect a lack of metastases to all lateral LNs. Our present results suggest that this laparoscopic ICG-guided SLN strategy may be a low-risk and time-saving method to prevent laparoscopic LLND in cases with negative lateral pelvic lymph nodes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08480-6.

Assessment of Frailty Can Guide Decision Making for Utilization of Sentinel Lymph Node Biopsy in Patients with Thick Melanoma

BACKGROUND

Sentinel lymph node biopsy (SLNB) is often omitted in selected patients with advanced primary melanoma, although the justification/criteria for omission have been debated.

OBJECTIVE

We sought to determine whether assessment of frailty could serve as an objective marker to guide selection for SLNB in patients with advanced primary melanoma.

METHODS

Patients presenting with clinical stage IIC (ulcerated, > 4 mm Breslow thickness) cutaneous melanoma from January 1999 through June 2019 were included. Frailty was assessed using the Memorial Sloan Kettering Frailty Index (MSK FI), a composite score of functional status and medical comorbidities. Five-year melanoma-specific survival (MSS) and overall survival (OS) were estimated using Cox regression, and predictors of OS were identified using competing risk models.

RESULTS

MSS did not differ between patients who did (n = 451) or did not undergo SLNB (n = 179) [63.2% vs. 65.0%, p = 0.14]; however, omission of SLNB was associated with decreased 5-year OS (29% vs. 44%, p < 0.001). In a multivariable competing risk model, selection for SLNB omission was an independent predictor of death from non-melanoma causes (hazard ratio [HR] 1.7, 95% confidence interval [CI] 1.2-2.3, p < 0.001). After incorporation of the MSK FI score into the multivariable model in this subset, MSK FI (HR 2.4, 95% CI 1.5-4.1, p < 0.001), but not SLNB omission, was an independent predictor of poorer OS.

CONCLUSION

We observed worse OS in patients with thick melanoma selected not to undergo SLNB, which was attributed to death due to non-melanoma causes. Formal assessment of frailty may provide an objective prognostic measure to guide selective use of SLNB in these patients.

Nodal Recurrence is a Primary Driver of Early Relapse for Patients with Sentinel Lymph Node-Positive Melanoma in the Modern Therapeutic Era

BACKGROUND

Management of patients with sentinel lymph node (SLN)-positive melanoma has changed dramatically over the last few years such that completion lymph node dissection (CLND) has become uncommon, and many patients receive adjuvant immunotherapy or targeted therapy. This study seeks to characterize patterns and predictors of early recurrence in this setting.

PATIENTS AND METHODS

All patients with primary cutaneous melanoma undergoing sentinel lymph node biopsy (SLNB) between 3/2016 and 12/2019 were identified. The subset with a positive SLN who did not undergo CLND were examined for further analysis of outcomes and predictors of recurrence.

RESULTS

Overall, 215 patients with SLN-positive melanoma who did not have CLND were identified. Adjuvant systemic therapy was administered to 102 (47%), with 93% of this subset receiving immunotherapy (n = 95). Median follow-up from SLNB was 20 months (IQR 12-28.5 months), and 57 patients (27%) recurred during this time. The SLN basin was the most common site of recurrence (n = 38, 67% of recurrence), with isolated nodal recurrence being the most common first site of recurrent disease (n = 22, 39% of recurrence). On multivariable analysis, lymphovascular invasion (LVI) of the primary tumor, two or more involved nodes, and > 1 mm nodal deposit were independently associated with higher rates of nodal relapse.

CONCLUSIONS

Nodal recurrence is a primary driver of early disease relapse for patients with SLN-positive melanoma who do not undergo CLND in the era of effective adjuvant systemic therapy. LVI, ≥ 2 nodes, or > 1 mm nodal disease identifies patients at particularly high risk of nodal relapse.

Development and Validation of Nomograms to Predict Local, Regional, and Distant Recurrence in Patients With Thin (T1) Melanomas

PURPOSE

Although the prognosis of patients with thin primary cutaneous melanomas (T1, ≤ 1.0 mm) is generally excellent, some develop recurrence. We sought to develop and validate a model predicting recurrences in patients with thin melanomas.

METHODS

A Dutch population-based cohort (n = 25,930, development set) and a cohort from an Australian melanoma treatment center (n = 2,968, validation set) were analyzed (median follow-up 6.7 and 12.0 years, respectively). Multivariable Cox models were generated for local, regional, and distant recurrence-free survival (RFS). Discrimination was assessed using Harrell's C-statistic for each outcome. Each nomogram performance was evaluated using calibration plots defining low-risk and high-risk groups as the lowest and top 5% of the nomogram risk score, respectively. The nomograms' C-statistics were compared with those of a model including the current American Joint Committee on Cancer staging parameters (T-stage and sentinel node status).

RESULTS

Local, regional, and distant recurrences were found in 209 (0.8%), 503 (1.9%), and 203 (0.8%) Dutch patients, respectively, and 23 (0.8%), 61 (2.1%), and 75 (2.5%) Australian patients, respectively. C-statistics of 0.79 (95% CI, 0.75 to 0.82) for local RFS, 0.77 (95% CI, 0.75 to 0.78) for regional RFS, and 0.80 (95% CI, 0.77 to 0.83) for distant RFS were obtained for the development model. External validation showed C-statistics of 0.80 (95% CI, 0.69 to 0.90), 0.76 (95% CI, 0.70 to 0.82), and 0.74 (95% CI, 0.69 to 0.80), respectively. Calibration plots showed a good match between predicted and observed rates. Using the nomogram, the C-statistic was increased by 9%-12% for the development cohort and by 11%-15% for the validation cohort, compared with a model including only T-stage and sentinel node status.

CONCLUSION

Most patients with thin melanomas have an excellent prognosis, but some develop recurrence. The presented nomograms can accurately identify a subgroup at high risk. An online calculator is available at www.melanomarisk.org.au.

Nuclear Medicine and Molecular Imaging in Nodal Staging and Surveillance of Ocular Melanoma: Case Reports and Review of the Literature

Ocular melanoma (OM) is a rare noncutaneous malignancy and consists of 2 different subtypes based on the anatomic location in the eye: uveal melanoma and conjunctival melanoma. Like cutaneous melanoma, OM benefits from nuclear medicine and molecular imaging in nodal staging and clinical management. Through the illustration of 2 distinctive cases, we aim to demonstrate the complementary roles of standard lymphoscintigraphy, advanced SPECT/CT, ¹⁸F-FDG PET/CT, and ¹⁸F-FDG PET/MRI in accurate nodal staging and surveillance of OM. We also review the epidemiology, existing staging guidelines, and management of uveal melanoma and conjunctival melanoma.

The role of FDG-PET-CT is limited in initial staging of nodal metastasis for thin cutaneous melanoma

INTRODUCTION

Positron emission tomography computed tomography (PET-CT) is often used to stage nodal metastases in thin cutaneous melanoma, with limited evidence.

METHODS

A retrospective review of patients with cutaneous malignant melanoma treated at our institution was performed from 2005 to 2015, identifying those who received a PET-CT prior to lymphadenectomy. Biopsy features, lymph node status, and PET-CT results were collected. We calculated the overall sensitivity, specificity, accuracy, likelihood ratios, and positive predictive value of PET-CT in identifying nodal metastases. Results were stratified by initial biopsy tumor depth.

RESULTS

We identified 367 cases; 95 obtained a PET-CT prior to lymphadenectomy. Overall, sensitivity and specificity of PET-CT was 34.6% and 95.4%, respectively. The positive likelihood ratio and negative likelihood ratio were 7.62 and 0.68, respectively. The accuracy was 78.2%. The positive predictive value for T3 and T4 melanomas were 100% and 81.4%, respectively. For thin melanomas, specificity and accuracy was 88.2% and 88.2%, respectively.

CONCLUSIONS

PET-CT has low specificity and its use alone is not recommended for initial staging of nodal metastases in thin cutaneous malignant melanoma.

Regional Lymph Node Metastases in Cutaneous Melanoma: A Single-Center Analysis from Southeast Europe

OBJECTIVE

Sentinel lymph node biopsy is the standard of care for nodal staging in clinically node-negative melanoma patients. Our goal was to present 10-year results of sentinel lymph node biopsy at our institution and to evaluate the clinicopathologic factors as potential predictors of sentinel lymph node and non-sentinel lymph node metastatic involvement in patients with cutaneous melanoma.

METHODS

We have analyzed clinicopathologic and lymphoscintigraphic characteristics in 420 patients with cutaneous melanoma who underwent sentinel lymph node biopsy between 2010 and 2019. In addition, we have examined the results of group of patients with positive sentinel lymph node biopsy undergoing complete lymph node dissection.

RESULTS

The overall detection rate of sentinel lymph node biopsies was 97.1%, of which 18.8% was metastatic. Drainage to one regional basin was seen in 345 patients (83.1%) and to multiple drainage regions in 71 patients (17%). In-transit lymph nodes were detected in 20 patients. On univariate logistic regression analysis, male gender, primary tumor thickness with nodular histology, acral location, presence of ulceration, and the number of nodes harvested were significantly associated with sentinel lymph node biopsy status (p < 0.05). On multivariate analysis, the Breslow thickness was the only independent predictor of sentinel lymph node biopsy status. The metastases in non-sentinel lymph node found in 26 patients with positive sentinel lymph node (35.6%) correlated on univariate, as well as on multivariate logistic regression, with tumor subtype and number of sentinel lymph node harvested.

CONCLUSION

In addition to the well-established primary tumor thickness as a predictor of sentinel lymph node biopsy positivity, we observed acral location and nodular melanoma subtype to significantly enhance the risk of metastases in sentinel lymph node(s). Primary tumor histology and number of nodes harvested were the only statistically significant variables predicting the non-sentinel lymph node status on multivariate analysis. Lymphoscintigraphy imaging characteristics were not significantly associated with sentinel lymph node status.

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.

Clinical Practice Guideline on Melanoma From the Spanish Academy of Dermatology and Venereology (AEDV)

Specialist approaches to the diagnosis and treatment of melanoma have undergone many changes. This guideline aims to provide Spanish dermatologists with evidence-based information for resolving the most common doubts that arise in clinical practice. Members of the Spanish Oncologic Dermatology and Surgery Group (GEDOC) with experience treating melanoma were invited to participate in drafting the guideline. The group developed a new guideline on the basis of existing ones, using the ADAPTE collaboration process, first summarizing the care process and posing relevant clinical questions, then selecting guidelines with the best scores according to the AGREE II (Appraisal of Guidelines for Research and Evaluation) tool. Finally, the group searched the selected guidelines for answers to the clinical questions, drafted recommendations, and sent them for external review. The guideline is structured around 21 clinical questions chosen for their relevance to issues that make clinical decisions about the management of melanoma difficult. Evidence from existing guidelines was used to answer the questions. A limitation of this guide derives from the scarce evidence available for answering some questions. Moreover, some areas are changing rapidly, so recommendations must be updated often. The present guideline offers answers to clinical questions about the routine management of melanoma in clinical practice and provides dermatologists with a reference to guide decisions, taking into consideration the resources available and patient preferences.