Evaluation of the Indications for Sentinel Node Biopsy in Early-Stage Melanoma with the Advent of Adjuvant Systemic Therapy: An International, Multicenter Study

Abstract

Background Patients presenting with early-stage melanoma (AJCC pT1b-pT2a) reportedly have a relatively low risk of a positive SNB (~5–10%). Those patients are usually found to have low-volume metastatic disease after SNB, typically reclassified to AJCC stage IIIA, with an excellent prognosis of ~90% 5-year survival. Currently, adjuvant systemic therapy is not routinely recommended for most patients with AJCC stage IIIA melanoma. The purpose was to assess the SN-positivity rate in early-stage melanoma and to identify primary tumor characteristics associated with high-risk nodal disease eligible for adjuvant systemic therapy Methods An international, multicenter retrospective cohort study from 7 large-volume cancer centers identified 3,610 patients with early primary cutaneous melanomas 0.8–2.0 mm in Breslow thickness (pT1b-pT2a; AJCC 8th edition). Patient demographics, primary tumor characteristics, and SNB status/details were analyzed. Results The overall SNB-positivity rate was 11.4% (412/3610). Virtually all SNB-positive patients (409/412; 99.3%) were reclassified to AJCC stage IIIA. Multivariate analysis identified age, T-stage, mitotic rate, primary site and subtype, and lymphovascular invasion as independent predictors of sentinel node status. A mitotic rate of >1/mm2 was associated with a significantly increased SN-positivity rate and was the only significant independent predictor of high-risk SNB metastases (>1 mm maximum diameter). Conclusions The new treatment paradigm brings into question the role of SNB for patients with early-stage melanoma. The results of this large international cohort study suggest that a reevaluation of the indications for SNB for some patients with early-stage melanoma is required.

Risk Stratification of Sentinel Node Metastasis Disease Burden and Phenotype in Stage III Melanoma Patients

“…group is no different from that of the SNBgroup. 4,26 Our data would indicate that the additional information afforded by the SNB for pT4b melanomas is limited, with no low-risk nodal micrometastatic disease in the SNB? group and no difference in DSS between the SNB-and SNB?…”

Melanoma surgery—An update

“…The implementation of American Joint Committee on Cancer version 8 (AJCC8) criteria for melanoma increased the number of patients with thin melanomas (Breslow thickness ≤1 mm) undergoing SNLB versus AJCC7. However, this did not result in an increased rate of SNL‐positive results 22,23 . A retrospective study on SNLB in T1b melanomas ( n = 203) from Italy registered positive SNL in 2.3% of melanomas 0.8 < 1.0 mm, and in 0% of melanomas <0.8 mm with ulceration.…”

“…However, this did not result in an increased rate of SNL-positive results. 22,23 A retrospective study on SNLB in T1b melanomas (n = 203) from Italy registered positive SNL in 2.3% of melanomas 0.8 < 1.0 mm, and in 0% of melanomas <0.8 mm with ulceration.…”

The Integrated 31-Gene Expression Profile Test (i31-GEP) for Cutaneous Melanoma Outperforms the CP-GEP at Identifying Patients who can Forego Sentinel Lymph Node Biopsy when Applying NCCN Guidelines

“…25,26 Moreover, recent evidence suggests that 99% of patients with a T1b or T2a tumor with a positive SLN are considered stage IIIA and have 5-year untreated survival rates of 94%. 2,27 Therefore, identifying patients with a low likelihood of SLN positivity who can safely forego SLNB and have high survival rates has the potential to reduce unnecessary SLNBs, surgery-associated complications, and healthcare costs.…”

“…Moreover, a recent study showed that patients with T1b/T2a tumors with a positive SLNB had survival equal to stage IIIA, with an associated 94% 5-year MSS. 2 Although recent discussion highlights that SLNB may have therapeutic benefits in SLNB-positive patients to control disease recurrence in the nodal basin, 3 these results highlight two important facts: 1) many patients may not need an SLNB and still have high survival rates and 2) recurrence or death prognostication in patients with a negative SLNB is critical to identify patients at high risk despite being SLN negative.…”