Sentinel Lymph Node Biopsy in a Young Child With Thick Cutaneous Melanoma

The article by Bisseck and colleagues highlights an important issue encountered increasingly by physicians-melanoma in children and adolescents. The incidence and mortality of melanoma continues to rise.[1] It is now the fifth most common cancer in men and the seventh most common cancer in women. In our practice at the Johns Hopkins Melanoma Center, we have treated a growing number of children and adolescents with melanoma, including many with stage III disease identified by sentinel node technology, similar to that described by Bisseck and colleagues. Staging Issues
There are three teaching points from this article that we would like to emphasize: (1) the role of the sentinel node in staging melanoma, (2) the clinical characteristics of melanoma in children and adolescents, and (3) the pathologic diagnosis of melanoma in children and adolescents. The sentinel node technique, pioneered by Dr. Donald Morton, has become a standard approach in the staging of melanoma at most centers. The Melanoma Staging Committee of the American Joint Commission on Cancer has recommended that all patients who potentially would be entered into melanoma clinical trials have their sentinel lymph nodes staged as an entry requirement.[2] Otherwise, it is difficult to distinguish between the impact of the natural history of melanoma in understaged patients (ie, those who do not have a sentinel node excision) from the treatment effect being evaluated in a clinical trial. At Johns Hopkins, patients with clinically negative nodes and whose melanoma is greater than 1 mm usually undergo excision of their sentinel node for staging purposes. In addition, patients with high-risk T1 melanoma (level IV invasion or ulcerated melanomas) are also considered for the sentinel lymph node staging. Whether survival is improved by the more accurate staging and early intervention with complete lymphectomy in patients with a clinically occult nodal metastasis must await the results of the international multi-institutional melanoma surgery trial. Treatment Issues
It is alarming to see the increasing number of children and adolescents who present with melanoma today. Several decades ago, this was a rare event. Major melanoma centers are now regularly encountering children and adolescents with invasive melanoma, including some with lymph node metastasis. Many of the children treated at our center do not have the usual risk factors associated with melanoma, such as family history, dysplastic nevi, congenital nevi, or multiple moles. No evidence to date demonstrates that survival rates in these younger populations are different from those in adults, using the standardized tumor, node, metastasis (TNM) prognostic and staging criteria.[2] In our practice at the Johns Hopkins Melanoma Center, we treat children, adolescents, and adults with melanoma in essentially the same way. This includes offering the sentinel node staging technique to patients who meet the criteria described above under Staging Issues. We agree with the treatment approach described by Bisseck et al. Many clinical protocols exclude melanoma patients who are less than 18 years old so that followup or high-dose interferon-alpha are the only options after surgery. The Spitz Nevus Factor
The pathologic diagnosis of melanoma can be problematic. As pointed out in this article, the Spitz nevus that can arise in children and adolescents has many of the histologic features of melanoma but is not a malignancy. Conversely, amelanotic melanomas are sometimes diagnosed as benign Spitz nevi and are undertreated until patients relapse with metastatic melanoma. Because of the overlapping histopathologic features of invasive melanoma and Spitz nevus in children and adolescents, we highly recommend that an experienced melanoma pathologist review the pathologic slides of these individuals so that they will be accurately diagnosed, staged, and treated. We commend Drs. Bisseck, Shen, and Pranikoff for highlighting their approach to this difficult clinical presentation and hope their patient has a successful clinical outcome.