18:40 - 19:15
Room: Emerald Ballroom
Rapid Fire Abstract Session (Non-CME)
Chair/s:
Mark B. Faries, Richard L. White, Jr.
Recurrence risk in patients with melanoma of the external ear: An investigation of surgical approach and sentinel lymph node status
Amanda Truong, John Hyngstrom, Robert Andtbacka, R. Dirk Noyes, Melissa Wright, John Snyder, Kenneth Grossmann, Douglas Grossman, Tawnya Bowles

Background

Surgical management of external ear melanomas represents a unique challenge due to the ear’s structural complexity and variable lymphatic drainage patterns. Few and conflicting studies of melanomas at this site have resulted in a lack of consensus regarding optimal treatment approach of the primary tumor and regional nodal basin. To address this, a retrospective cohort study was performed to evaluate primary tumor characteristics and treatment decisions, as well as their impact on local, regional, and distant recurrence.

Materials and Methods

Patients diagnosed with invasive external ear melanoma between 2000 and 2011 were identified from the University of Utah and Intermountain Healthcare melanoma databases. Patients older than 18 were included for analysis if they had documented invasive primary melanoma of the external ear, had at least 2 years of documented follow-up, and had no synchronous metastatic disease at time of diagnosis. Patient demographics, tumor site, histologic characteristics, surgical technique (including cartilage sparing vs. cartilage removal procedures), sentinel lymph node location and status, and follow-up data were evaluated using descriptive statistics and Fisher’s exact test for analysis of recurrence risk.

Results

A total of 156 patients were identified, median age was 62.5 years, 85.9% were male, and mean follow-up was 5.5 years. Primary melanoma location on the external ear included helix (61.5%), lobe (13.5%), and other (25.0%). 75.3% of ear melanomas were diagnosed as stage IA/IB. Lentigo maligna melanoma was the most common histologic subtype (36.6%) and median Breslow depth was 0.86 mm (range: 0.1-7.0 mm). Cartilage sparing surgery was performed in 29 (19.2%) patients, whereas 122 (80.8%) patients had cartilage removal, including 14 (9.5%) patients who underwent a complete auriculectomy with prosthetic reconstruction. 99 (63.5%) patients underwent sentinel lymph node biopsy, with sentinel lymph node(s) identified in 100% of patients and a median number of four nodes. 14.1% of these patients had micrometastatic nodes. Twenty-six (16.7%) patients had a recurrence with a median time to recurrence of 2.3 years (range: 0.4 – 5.5 years). Of the patients with a recurrence, 57.7% recurred initially at a distant site, most commonly to the lung. Increased recurrence risk was associated with primary tumor location (non-helix sites), increased Breslow depth, more advanced initial stage at diagnosis, and micrometastatic sentinel lymph nodes. There was no significant association between recurrence risk and surgical technique, including whether or not cartilage was removed in early stage lesions.

Conclusions

This study comprises one of the largest cohorts of external ear melanomas and sentinel lymph node biopsy. In addition to identifying and reinforcing previously established risk factors for recurrence, our study also highlights the feasibility and importance of sentinel lymph node biopsies in stratifying recurrence risk, even in this area of variable lymphatic drainage. We also report that choice of surgical approach of the primary tumor, including sparing cartilage or not, was not associated with increased local, regional, or distant recurrence risk. Our findings provide more robust data to inform future surgical guidelines of this intricate cutaneous region.


Reference:
22-02
Session:
Session 22: Rapid Fire Abstract Session: Cancer Metastasis & Treatment
Presenter/s:
Amanda Truong
Presentation type:
Rapid Fire Oral Presentation
Room:
Emerald Ballroom
Chair/s:
Mark B. Faries, Richard L. White, Jr.
Date:
Friday, April 21, 2017
Time:
18:45 - 18:50
Session times:
18:40 - 19:15