Melanoma: A Head and Neck Surgeon's Perspective

Educational Objectives

The goal of this program is to improve management of melanoma. After hearing and assimilating this program, the clinician will be better able to:

1. Use appropriate imaging modalities to assess melanoma in the head and neck region.

Summary

Epidemiology: the incidence of melanoma in the United States has nearly doubled in the last 12 yr; melanoma is more common in men overall, but more common in women and persons <50 yr of age; the lifetime risk is 1 in 38 in the White population, 1 in 1000 in the non-White population, and 1 in 167 for the Hispanic population; ≈30% of malignant melanomas involve the head and neck (HN) region; the average age of diagnosis is 65 yr of age; the mortality rate is decreasing because of early detection and immunotherapy

Challenges in HN melanoma: cosmetic considerations are more significant in HN melanoma than in other regions; functional challenges are related to the close proximity of organs during resection and reconstruction; the diverse lymphatic drainage of the head and neck complicates sentinel lymph node (SLN) resection

Diagnosis: excisional biopsy is preferred for smaller lesions to ascertain their depth; a punch biopsy of the thickest portion is appropriate for larger lesions; shave biopsies should be avoided

Workup: history and physical examination is sufficient for stage 0 disease; regional investigations (eg, ultrasonography [US], contrast computed tomography [CT]) may be preferable for melanoma of <8-mm depth, especially in patients who are not also undergoing SLN biopsy (SLNB); SLNB should be considered for melanoma of >0.8-mm or <0.8-mm thickness with adverse features; extensive imaging (eg, CT of chest, abdomen, pelvis, and brain, magnetic resonance imaging, positron emission tomography) is indicated to rule out central nervous system involvement for stage 3 melanoma; lactate dehydrogenase levels may be evaluated in cases of advanced disease

Sentinel lymph node biopsy: a minimally invasive procedure for detection of occult nodal disease; adds to staging information; may provide therapeutic benefits in cases of intermediate-thickness melanoma by identifying patients for, eg, close observation, therapeutic neck dissection, immunotherapy; may detect non-SLN positivity, which may be more common in the HN region; 20% of patients with stage 1 and 2 melanoma are upstaged to stage 3, and the remaining 80% need not undergo further surgery or immunotherapy; the incidence of occult positive melanoma on SLNs increases with the thickness of the primary lesion (ie, an incidence of 5% for thin lesions and an incidence of 35% for lesions with a thickness of >4mm); 15% to 20% patients with stage 1 and 2 lesions may progress to occult stage 3 disease and are at high risk for recurrence

Additional tests: patients undergo lymphoscintigraphy 24 hr before surgery and imaging >1 hr after injection; single-photon emission CT (SPECT) provides a 3-dimensional representation which allows the depth of the lesions to be accurately assessed and the number of nodes yielded; gamma probes may distinguish lymph nodes from fat in the HN region; SLNB may identify micrometastatic disease by histology or polymerase chain reaction analysis, helps determine treatment strategies and minimizes morbidity, and is the standard of care for melanoma, Merkel cell carcinoma, and advanced squamous cell carcinoma; a study of 10-yr follow-up of patients who underwent SLNB found high success rates at finding nodes without major complications

Neck dissection: the MSLT-II trial (Faries et al, 2017) found no overall survival benefit for neck dissections in cases of SLN metastases, but an increased rate of disease control in the regional nodes; systemic therapy is considered for most patients; patients with positive non-SLNs may benefit from neck dissection

Surgical margins: small tumors (<1 mm depth) require a 1-cm peripheral margin; a wider margin is recommended for tumors near, eg, the scalp, with increased depth; a 2-cm margin may be difficult to maintain if important structures are in close proximity; margins may be modified based on functional and anatomic considerations

Lymphatic drainage: tissue that is anterior to the ear canal drains to the parotid or submandibular lymph nodes; tissue that is posterior to the ear canal drains to the occipital and postauricular lymph nodes and further to level 5 lymph nodes

Ultrasonography: useful for surveillance but does not replace SLNB for diagnosis; may be used for observation in nonsurgical candidates; abnormal results on US may prompt ultrasound-guided fine needle aspiration biopsy

Reconstruction: defects may be reconstructed with local flaps (eg, O-to-S flap), free flaps, dermal repair scaffold (eg, PriMatrix); auriculectomy may be reconstructed with skin grafts (in patients with patent ear canals) and a prosthetic ear; bone-anchored hearing aids may remedy hearing loss; for the nose, nasolabial and forehead flaps or a prosthetic may be used

Readings

Faries MB, Thompson JF, Cochran AJ, et al. Completion dissection or observation for sentinel-node metastasis in melanoma. N Engl J Med. 2017;376(23):2211-2222; Gershenwald JE, Scolyer RA, Hess KR, et al. Melanoma staging: Evidence-based changes in the American Joint Committee on Cancer eighth edition cancer staging manual. CA Cancer J Clin. 2017;67(6):472-492.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Gaylis was recorded at Melanoma 2022: 32nd Annual Cutaneous Malignancy Update, held January 26, 2022, in San Diego, CA, and presented by Scripps Health. For more information about upcoming CME activities from this presenter, please visit www.scripps.org/melanomacme. Audio Digest thanks the speakers and presenters for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0.75 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0.75 CE contact hours.

Lecture ID:

OT570602

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.