SLNB and thick melanomas

 Original Article

Is there a benefit to sentinel lymph node biopsy in patients with T4 melanoma?

Csaba Gajdos, MD 1, Kent A. Griffith, MPH, MS 2, Sandra L. Wong, MD 1, Timothy M. Johnson, MD 1 3, Alfred E. Chang, MD 1, Vincent M. Cimmino, MD 1, Lori Lowe, MD 4, Carol R. Bradford, MD 5, Riley S. Rees, MD 1, Michael S. Sabel, MD 1 *

1Department of Surgery, University of Michigan Health System, Ann Arbor, Michigan 2Biostatistics Core, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan 3Department of Dermatology, University of Michigan Health System, Ann Arbor, Michigan 4Department of Pathology, University of Michigan Health System, Ann Arbor, Michigan 5Department of Otolaryngology, University of Michigan Health System, Ann Arbor, Michigan

email: Michael S. Sabel (msabel@umich.edu)

^*Correspondence to Michael S. Sabel, 304 Cancer Center, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0932

Fax: (734) 647-9647

KEYWORDS

Breslow depth • interferon • melanoma • sentinel lymph node biopsy

ABSTRACT

BACKGROUND:

Controversy exists as to whether patients with thick (Breslow depth >4 mm), clinically lymph node-negative melanoma require sentinel lymph node (SLN) biopsy. The authors examined the impact of SLN biopsy on prognosis and outcome in this patient population.

METHODS:

A review of the authors' institutional review board-approved melanoma database identified 293 patients with T4 melanoma who underwent surgical excision between 1998 and 2007. Patient demographics, histologic features, and outcome were recorded and analyzed.

RESULTS:

Of 227 T4 patients who had an SLN biopsy, 107 (47%) were positive. The strongest predictors of a positive SLN included angiolymphatic invasion, satellitosis, or ulceration of the primary tumor. Patients with a T4 melanoma and a negative SLN had a significantly better 5-year distant disease-free survival (DDFS) (85.3% vs 47.8%; P < .0001) and overall survival (OS) (80% vs 47%; P < .0001) compared with those with metastases to the SLN. For SLN-positive patients, only angiolymphatic invasion was a significant predictor of DDFS, with a hazard ratio of 2.29 (P = .007). Ulceration was not significant when examining SLN-positive patients but the most significant factor among SLN-negative patients, with a hazard ratio of 5.78 (P = .02). Increasing Breslow thickness and mitotic rate were also significantly associated with poorer outcome. Patients without ulceration or SLN metastases had an extremely good prognosis, with a 5-year OS >90% and a 5-year DDFS of 95%.

CONCLUSIONS:

Clinically lymph node-negative T4 melanoma cases should be strongly considered for SLN biopsy, regardless of Breslow depth. SLN lymph node status is the most significant prognostic sign among these patients. T4 patients with a negative SLN have an excellent prognosis in the absence of ulceration and should not be considered candidates for adjuvant high-dose interferon. Cancer 2009. © 2009 American Cancer Society.

Melanoma Excision Margins

Surgical excision margins for primary cutaneous melanoma

Whilst melanoma accounts for only 5% of skin cancers, it is important because it is the cause of 75% of all skin cancer deaths. For primary cutaneous melanoma, standard treatment is complete surgical removal of the melanoma with a safety margin some distance from the visible edges of the primary tumour. The purpose of the safety margin is to remove both the primary tumour and any melanoma cells that might have spread into the surrounding skin. However, the optimal width of the safety (excision) margin remains unclear.

This systematic review summarises the evidence about how much tissue (safety margin) should be removed for primary cutaneous melanoma (skin cancer). Excision margins are important because there could be a trade-off between a better cosmetic result but poorer long-term survival if excision margins become too narrow.

It is important to note that for the purposes of this review we consider only invasive melanoma - that has invaded into the deeper layer of the skin (dermis) - and not melanoma-in-situ where the melanoma cells are confined to the outermost layer of the skin (epidermis).

We found five published randomised trials, none of which showed a statistically significant difference in overall survival for patients who had either narrow or wide removal of the melanoma and surrounding tissue. Similarly, our meta-analysis showed there was no statistically significant difference in overall survival between the two groups treated with either narrow or wide excision.

The summary estimate for overall survival favoured wide excision by a small degree, but the result was not significantly different. This result is compatible with both a 5% relative reduction in overall mortality favouring narrower excision and a 15% relative reduction in overall mortality favouring wider excision.

Current randomised trial evidence is insufficient to address optimal excision margins for primary cutaneous melanoma.

The Cochrane Review on this issue can be downloaded here

Acral Lentiginous Melanoma removal

Acral lentiginous melanoma: conventional histology vs. three-dimensional histology
V. Lichte, H. Breuninger, G. Metzler, H.M. Haefner and M. Moehrle
Department of Dermatology, Universitätsklinikum Tübingen, Eberhard-Karls-Universität, Liebermeisterstr. 25, D-72076 Tübingen, Germany
British Journal of Dermatology
Volume 160 Issue 3, Pages 591 - 599
Correspondence to Verena Lichte.
E-mail: verena.lichte@med.uni-tuebingen.de

ABSTRACT
Background Patients with acral lentiginous melanoma (ALM) seem to have a poor prognosis. ALMs represent 4–10% of cutaneous melanomas in white populations. Surgery is mostly based on conventional histological evaluation. With micrographic surgery, continuously spreading tumours can be excised with smaller excision margins for better cosmesis and function.

Objectives Clinical parameters and surgical strategies influencing the prognosis of patients with ALM were evaluated.

Methods Two hundred and forty-one patients (44% male, 56% female) with stage I/II ALM were recorded during 1980–2006. One hundred and thirty-three patients underwent complete histology of three-dimensional excision margins (3D histology) using the paraffin technique. Risk factors for disease-specific and recurrence-free survival were estimated.

Results Patients were aged 26–87 years (median 63) with median tumour thickness of 2·0 mm. The median follow-up was 41 months. Multivariate analysis identified ulceration, conventional histology and tumour thickness as risk factors for recurrence-free and disease-specific survival. Using 3D histology, excision margins were significantly smaller (median 7 vs. 20 mm) without an increased risk of local recurrences. Patients with 3D histology had a 5-year survival of 81% compared with 63% with conventional histology. Retrospective analysis with immunohistological methods (anti-Melan-A) could improve the diagnostic specificity in detecting further melanocytic cell nests.

Conclusions Clinical and surgical risk factors seem to have different influences on the outcome of ALM. 3D histology allows reduction of excision margins by two-thirds without an increased risk of local recurrences and with better prognosis. 3D immunohistology could be a valuable diagnostic tool to reduce the rate of local recurrences.