Melanoma Lymph Nodes with Dr. Mark Faries

Welcome back to the SO Files! On today’s show we focus on melanoma and welcome Dr. Mark Faries onto the podcast. We discuss his role in the MSLT-I and MSLT-II trials as well as how their results have influenced the most recent editions of the NCCN and AJCC clinical practice guidelines. Before jumping into our interview with Dr. Faries, we take some time to introduce the basic staging principles for melanoma and the highlights of the MSLT-I and MSLT-II trials.

Dr. Faries is the head of the division of surgical oncology and co-director of the melanoma program at the Angeles Clinic and Research Institute, as well as a Professor of Surgery and Surgical Director of Experimental Therapeutics at Cedars Sinai Medical Center. He is a member of the AJCC Melanoma Staging Committee and the American Society of Clinical Oncology / Society of Surgical Oncology Melanoma guidelines panel. He has also published numerous chapters and articles on melanoma research and therapy, and was the lead investigator on the recently published, and practice changing, MSLT-II trial.

0-12:00 – Brad and Alston give overview of melanoma workup and 8th edition AJCC staging. Brief intro to MSLTI and MSLTII.

12:00- Interview with Dr. Faries

Background:

AJCC 8th Edition (2018) Melanoma Staging

An updated, evidence based overview of melanoma staging.

NCCN Clinical Practice Guidelines (v3.2018)

Clinical practice guidelines for the treatment of melanoma from the national comprehensive cancer network, version 3.2018. 

Relevant Reading:

1. MSLT-I Trial;  MSLT-I Trial – 10 year followup

Sentinel-Node Biopsy or Nodal Observation in Melanoma; Morton et al. NEJM, Sept 2006

Final Trial Report of Sentinel-Node Biopsy versus Nodal Observation in Melanoma; Morton et al. NEJM Feb 2014

Patients (n = 2001) with primary cutaneous melanoma were randomly assigned to either wide excision (WE) and postoperative observation of regional lymph nodes with lymphadenectomy if nodal relapse occurred [observation group], or to wide excision (WE) and sentinel-node biopsy (SLNBx) with immediate lymphadenectomy if nodal micrometastases were detected on biopsy [biopsy group]. No difference in 10-yr melanoma-specific survival seen in overall treatment group. But significantly improved disease-free survival rates were seen in biopsy group compared to observation group among patients with intermediate-thickness melanoma, defined as 1.2 to 3.5mm depth, 71% vs 64%, p=0.01; as well as thick melanoma, defined as > 3.5mm – 50% vs 40%, p=0.03. In addition, among patients with nodal mets and intermediate thickness melanoma, 10 year melanoma specific survival was 62.1% for those who got upfront SLN biopsy followed by dissection, versus 41.5% in the observation group (HR 0.56, p=0.006).

Takeaway – Biopsy-based staging of intermediate or thick primary melanomas provides important prognostic information. In addition SLN biopsy followed by lymphadenectomy appears to increase melanoma specific survival for patients who have involved lymph nodes and intermediate thickness disease.

2. MSLT-II Trial

Completion Dissection of Observation for Sentinel-Node Metastasis in Melanoma; Faries et al, NEJM, June 2017.

After MSLT-I, SLNBx was associated with increased melanoma-specific survival among patients with node-positive, intermediate-thickness melanomas (1.2 to 3.5mm). This trial set out to determine the value of completion lymph-node dissection at the time of surgery. Randomly assigned patients (n = 1934) with sentinel-node metastases to immediate completion lymph-node dissection (dissection group) or nodal observation with ultrasonography (observation group). The primary end point was melanoma-specific survival. Mean 3-yr melanoma-specific survival was similar between groups (86% in both) at a median follow-up of 43 months. However, rate of disease-free survival was higher in the dissection group (68% vs 63%, p=0.05)) which was primarily attributed to better regional nodal disease control at 3 years (92% vs 77%, p<0.001)

Takeaway – Immediate completion LN dissection increased the rate of regional disease control and provided prognostic information, but didn’t increase melanoma-specific survival among patients with melanoma and sentinel-node metastases.