Lower prevalence of lymphatic metastasis and poorer survival of the sentinel node-negative patients limit the prognostic value of sentinel node biopsy for head or neck melanomas

Association of Complex Lymphatic Drainage in Head and Neck Cutaneous Melanoma With Sentinel Lymph Node Biopsy Outcomes: A Cohort Study and Literature Review

Importance

Although sentinel lymph node biopsy (SLNB) is a vital staging tool, its application in head and neck melanoma (HNM) is complicated by a higher false-negative rate (FNR) compared with other regions. This may be due to the complex lymphatic drainage in the head and neck.

Objective

To compare the accuracy, prognostic value, and long-term outcomes of SLNB in HNM with melanoma from the trunk and limb, focusing on the lymphatic drainage pattern.

Design, Setting, and Participants

This cohort observational study at a single UK University cancer center included all patients with primary cutaneous melanoma undergoing SLNB between 2010 to 2020. Data analysis was conducted during December 2022.

Exposures

Primary cutaneous melanoma undergoing SLNB between 2010 to 2020.

Main Outcomes and Measures

This cohort study compared the FNR (defined as the ratio between false-negative results and the sum of false-negative and true-positive results) and false omission rate (defined as the ratio between false-negative results and the sum of false-negative and true-negative results) for SLNB stratified by 3 body regions (HNM, limb, and trunk). Kaplan-Meier survival analysis was used to compare recurrence-free survival (RFS) and melanoma-specific survival (MSS). Comparative analysis of detected lymph nodes on lymphoscintigraphy (LSG) and SLNB was performed by quantifying lymphatic drainage patterns by number of nodes and lymph node basins. Multivariable Cox proportional hazards regression identified independent risk factors.

Results

Overall, 1080 patients were included (552 [51.1%] men, 528 [48.9%] women; median age at diagnosis 59.8 years), with a median (IQR) follow-up 4.8 (IQR, 2.7-7.2) years. Head and neck melanoma had a higher median age at diagnosis (66.2 years) and higher Breslow thickness (2.2 mm). The FNR was highest in HNM (34.5% vs 14.8% trunk or 10.4% limb, respectively). Similarly, the false omission rate was 7.8% in HNM compared with 5.7% trunk or 3.0% limbs. The MSS was no different (HR, 0.81; 95% CI, 0.43-1.53), but RFS was lower in HNM (HR, 0.55; 95% CI, 0.36-0.85). On LSG, patients with HNM had the highest proportion of multiple hotspots (28.6% with ≥3 hotspots vs 23.2% trunk and 7.2% limbs). The RFS was lower for patients with HNM with 3 or more affected lymph nodes found on LSG than those with fewer than 3 affected lymph nodes (HR, 0.37; 95% CI, 0.18-0.77). Cox regression analysis showed head and neck location to be an independent risk factor for RFS (HR, 1.60; 95% CI, 1.01-2.50), but not for MSS (HR, 0.80; 95% CI, 0.35-1.71).

Conclusions and Relevance

This cohort study found higher rates of complex lymphatic drainage, FNR, and regional recurrence in HNM compared with other body sites on long-term follow-up. We advocate considering surveillance imaging for HNM for high-risk melanomas irrespective of sentinel lymph node status.

Machine learning directed sentinel lymph node biopsy in cutaneous head and neck melanoma

BACKGROUND

The specificity of sentinel lymph node biopsy (SLNB) for detecting lymph node metastasis in head and neck melanoma (HNM) is low under current National Comprehensive Cancer Network (NCCN) treatment guidelines.

METHODS

Multiple machine learning (ML) algorithms were developed to identify HNM patients at very low risk of occult nodal metastasis using National Cancer Database (NCDB) data from 8466 clinically node negative HNM patients who underwent SLNB. SLNB performance under NCCN guidelines and ML algorithm recommendations was compared on independent test data from the NCDB (n = 2117) and an academic medical center (n = 96).

RESULTS

The top-performing ML algorithm (AUC = 0.734) recommendations obtained significantly higher specificity compared to the NCCN guidelines in both internal (25.8% vs. 11.3%, p < 0.001) and external test populations (30.1% vs. 7.1%, p < 0.001), while achieving sensitivity >97%.

CONCLUSION

Machine learning can identify clinically node negative HNM patients at very low risk of nodal metastasis, who may not benefit from SLNB.

Sentinel lymph node biopsy in head and neck cutaneous melanomas: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Head and neck melanomas (HNMs) behave differently from cutaneous melanomas in other sites, and the efficacy of sentinel lymph node biopsy (SLNB) for patients with HNMs remains controversial.

METHODS

Studies on prognosis following SLNB were included. The prognostic role of SLNB and other potential predictors were analyzed using pooled relative risk (RR) or hazard ratio (HR).

RESULTS

Pooled statistics showed that SLNB improved overall survival of HNMs patients (HR = 0.845; 95% CI: 0.725-0.986; P = .032). The positive status of SN was proved as a risk factor of poor prognosis in HNMs (HR = 3.416; 95% CI: 1.939-6.021; P < .001). SLNB did not have significant correlation with lower recurrences (RR = .794; 95% CI: 0.607-1.038; P = .091).

CONCLUSIONS

SLNB is associated with better overall survival and the SN status is a promising risk factor of poor prognosis for HNMs patients.

[Treatment of cutaneous malignant melanoma in the head and neck region : An update]

Major progress has been made in the treatment of malignant melanoma during recent years. On the one hand, reliable evidence-based recommendations regarding surgical resection as well as lymph node management have been established on the basis of results from randomized multicenter studies. On the other hand, the advent of targeted therapies has led to spectacular improvements in the treatment of metastasized melanomas. Knowledge concerning treatment algorithms and updates thereof is also essential for maxillofacial surgeons. The German S3 guideline on diagnosis and treatment of melanoma was published in 2013 and revised in 2016 and 2018. This article informs readers about these developments and addresses the items relevant for treatment of head and neck melanomas in particular.

Clinicopathologic Factors Predictive of Occult Lymph Node Involvement in Cutaneous Head and Neck Melanoma

Objectives

Evaluate clinicopathologic factors contributing to regional lymph node (LN) metastases in cutaneous head and neck melanoma (HNM).

Study Design

Retrospective review of a national cancer database.

Setting

National Cancer Database (2004-2012).

Methods

National Cancer Database (NCDB) cases diagnosed between 2004 and 2012 were reviewed. Inclusion criteria were head and neck cutaneous site codes, melanoma histology codes, and clinically node-negative status. Independent, clinicopathologic factors associated with pathologic positive LN status were identified by multivariable logistic regression. Subset analysis was performed on thin melanoma cases of 0.75 to 1 mm tumor depth to determine factors predictive of LN involvement and survival.

Results

Of 66,495 cases meeting inclusion criteria, 18,882 had nodes examined pathologically with 9.7% presenting with occult positive LN involvement. Mean (SD) age was 62.9 (16.13) years, and primary sites were scalp and neck (42.2%), face (40.2%), and external ear, lip, or eyelid (7.6%). Multivariable analysis found younger age; primary site of cutaneous scalp, neck, or face; increasing thickness; mitoses; ulceration; and vertical growth phase presence were independently associated with LN positivity ( P < .001). Only 2% of 0.75- to 1.0-mm Breslow thickness cases had regional LN involvement, and age >70 was negatively associated with LN involvement ( P = .002) in this subset.

Conclusion

This is the largest study examining factors predictive of occult LN involvement in patients with clinical node-negative cutaneous HNM who may benefit from sentinel LN biopsy. Primary sites of external ear, lip, or eyelid are less likely to present with occult nodal involvement, and older patients with T1a melanoma ≥0.76 mm are unlikely to present with regional node metastasis and may not require sentinel node guided management.

Association of sentinel lymph node biopsy with survival for head and neck melanoma: survival analysis using the SEER database

IMPORTANCE

Sentinel lymph node biopsy (SLNB) provides prognostic information for melanoma; however, a survival benefit has not been demonstrated.

OBJECTIVE

To assess the association of SLNB with survival for melanoma arising in head and neck subsites (HNM).

DESIGN, SETTING, AND PARTICIPANTS

Propensity score-matched retrospective cohort study using the Surveillance Epidemiology and End Results (SEER) database to compare US patients with HNM meeting current recommendations for SLNB, treated from 2004 to 2011 with either (1) SLNB with or without neck dissection, or (2) no SLNB or neck dissection.

INTERVENTIONS

SLNB with or without neck dissection.

MAIN OUTCOMES AND MEASURES

Disease-specific survival (DSS) estimates based on the Kaplan-Meier method, and Cox proportional hazards modeling to compare survival outcomes between matched pair cohorts.

RESULTS

A total of 7266 patients with HNM meeting study criteria were identified from the SEER database. Matching of treatment cohorts was performed using propensity scores modeled on 10 covariates known to be associated with SLNB treatment or melanoma survival. Cohorts were stratified by tumor thickness (thin, >0.75-1.00 mm Breslow thickness; intermediate, >1.00-4.00 mm; and thick, >4.00 mm) and exactly matched within 5 age categories. In the intermediate-thickness cohort, 2808 patients with HNM were matched and balanced by propensity score for SLNB treatment; the 5-year DSS estimate for those treated by SLNB was 89% vs 88% for nodal observation (log-rank P = .30). The hazard ratio for melanoma-specific death was 0.87 for those undergoing SLNB (95% CI, 0.66-1.14; P = .31). In each of the other cohorts analyzed, including those with thin and thick melanomas, and cohorts with melanoma overall, no significant difference in DSS was demonstrated.

CONCLUSIONS AND RELEVANCE

This SEER cohort analysis demonstrates no significant association between SLNB and improved disease-specific survival for patients with HNM.