Guidelines of care for the management of primary cutaneous melanoma

The American Academy of Dermatology commissioned a working group to author and update guidelines on the clinical management of primary cutaneous melanoma. The guidelines should be carefully read by those involved in the care of melanoma patients. Nevertheless, here is a quick synopsis of key recommendations:

Bichakjian CK et al. . J Am Acad Dermatol 2011 Nov; 65:1032.

Medline abstract (Free)

Pathology

The essential components of a melanoma pathology report are thickness, ulceration, dermal mitotic rate (mitoses/mm²), peripheral and deep margins, Clark level, and microsatellitosis (a frequently overlooked feature). The presence of microsatellitosis in even a thin melanoma upstages the cancer to Stage IIIb and may trigger a consultation with medical oncology.

Staging

The 2009 American Joint Committee on Cancer (AJCC) staging system eliminated Clark levels as a parameter, retained ulceration, and introduced mitotic count (mitoses/mm²). The most significant change for the practitioner will be the upstaging in patients with thin melanomas and a mitotic count >1.0/mm² to Stage Ib; in the past, such cancers would have been Stage Ia if the lesion was nonulcerated and the Clark level

Biopsy

The recommendation for a pigmented lesion is still complete removal with 1–3-mm margins.

Partial sampling is acceptable in certain select situations (e.g., facial lesions, large pigmented lesions).

Surgical margins

For the most part, these have been standardized based on results of surgical trials:

• In situ: 0.5–1 cm
• <1 mm: 1 cm
• 1.01–2.0 mm: 1–2 cm
• >2.0 mm: 2 cm

Surgical margins have become narrower over time. Current recommendations place the maximum margin at 2 cm. The role of Mohs surgery for melanoma is not specifically addressed within these guidelines.

Postmelanoma surveillance

The focus should be on physical examination and review of systems. Routine laboratory and radiologic examinations are not recommended for asymptomatic patients. Follow-up intervals should be determined by patient risk (e.g., thickness of tumor).

Sentinel lymph node biopsies (SNLBs)

SLNB is not indicated in patients with in situ melanoma. SLNB should be considered in patients with melanoma thickness >1 mm. Most dermatologists are now familiar with the issues surrounding SLNB. Although the survival benefit of SLNB remains controversial, SLNB is an appropriate staging procedure (e.g., for separating Stage III from localized Stage I and II disease). Medical oncologists also use this staging step for determining the administration of interferon.

A patient with a 0.75-mm–thick melanoma and 1 mitosis/mm² is currently Stage Ib. Is SLNB indicated? The guidelines committee discusses this specific issue in depth. This subgroup may represent a large proportion of patients (median melanoma thickness diagnosed in the U.S. is <1.0 mm).

Comment: SLNB has not been associated with a survival benefit. For patients with melanomas 0.75 mm thick, the sentinel node is unlikely to be positive and survival is quite favorable. SLNB may clarify prognosis in the presence of other adverse features (e.g., angiolymphatic invasion, positive deep margin, or young age). I tend to use SLNB very judiciously in this group, and most of my patients understand the limited utility.

For patients with stage T1b melanomas of 0.76–1.00-mm thickness, I attempt to achieve agreement between the patient and myself, taking into consideration survival benefit (none documented), side effects (minimal with straightforward SLNB), ease of procedure (midback vs. extremity), comorbidities, downstream implications (completion lymphadenectomy, interferon use), and implications of clinical relapse in the regional basin at a later date (surgical challenges and remorse). Some patients will focus on the lack of survival benefit and decline, which is acceptable as long as the decision has been well informed and documented. Other patients want to know and do everything possible and sign on immediately. There are no right answers, and every conversation is different, but documentation is crucial.

Guidelines are not meant to be exact recipes for clinical decision making. Multiple rounds of debate among committee members with diverse viewpoints occurred during the writing process. Consonance with other national organizations (e.g., National Comprehensive Cancer Network) is important because melanoma management is multidisciplinary, and patients should receive similar recommendations from providers. Like most guidelines and staging criteria, the document is organic and can be expected to evolve over time.

Hensin Tsao, MD, PhD  Dr. Tsao served on the committee that authored these guidelines.

Published in Journal Watch Dermatology October 28, 2011