Malignant Spitzoid Melanoma: An Overview
What is Spitzoid Melanoma?
Spitzoid melanoma is a specific type of skin cancer, also known as epithelioid cell naevus, melanocytomas of Spitz, and Spitz tumors. Initially, they manifest as round, dull, pink growths about a centimeter in diameter over a 6 to 12 month period, and then darken to a brown or tan shade. However, they do not always darken, and malignant Spitzoid melanomas have often been wrongly diagnosed as benign Spitz nevi. One diagnostic difference has seen epidermal atrophy associated with the malignant form, as opposed to hyperplasia, more commonly found with the benign Spitz nevi. Also, ulceration may be present with both forms, but is more often found with the malignant melanoma. Instances of mitosis in the deeper portions of the growth are signs of malignancy, as are angiolymphatic spread, perineural invasion and necrosis.
<img src="https://upload.wikimedia.org/wikipedia/commons/thumb/0/00/Melanoma_sem.jpg/120px-Melanoma_sem.jpg" alt="Article Image" title="Article Image"> Melanoma at 130X magnification. Image Credit: Wikimedia Commons.
Causes
Studies of malignant spitzoid melanomas have shown that many result from a mutation in the B-RAF gene. The Gill M. et. al. study in Cancer 2004 (101:2636-2640) looked at the relationship between these mutations (and mutations in the N-RAS and K-RAS genes) and malignant manifestations of the melanoma. However, that study found no significant genetic differences between the malignant tumors and the benign Spitz nevi – again, these growths are often confused in the diagnostic stage.
Treatment Methods
Currently, the FDA has only approved adjuvant interferon (IFN) alfa-2b for this type of melanoma in stages IIB, IIC and III. Surgical removal of the lesions is also a common treatment. In this instance, the tumor itself is taken out, along with some of the healthy tissue around it. The deeper the melanoma, the more healthy tissue will come out.
Melanoma is one of the riskier forms of cancer when it comes to spreading, or metastasis. In cases of malignant melanoma, a lymph node biopsy frequently follows the removal of the lesions, to see if the cancer has started to spread. Lymph nodes containing cancer will also come out. In some cases of malignant Spitzoid melanoma, radiation therapy can follow surgery.
Prognosis
Children and adolescents rebound fairly well from malignant spitzoid melanoma, as well as other forms of melanoma, provided diagnosis happens at an early stage. Five-year survival for adolescents and children who have had melanoma is around 90%, and is well above 90% in cases where the disease is localized. For those whose cancer has spread to the nodes, 60% have a five-year survival rate. Metastasis obviously makes long-term survival less likely, and more aggressive plans that include single-agent chemotherapy or biochemotherapy come into play. As of November, 2010, there is one experimental trial for melanoma – ECOG-1697 – that involves a month of high-dose interferon-alpha-2b for various forms of the disease.
External References
https://www.cancer.umn.edu/research/programs/peccc/c3feb05.html
https://cme.medscape.com/viewarticle/729813_3
https://www.mayoclinic.org/melanoma/treatment.html
https://www.cancer.gov/cancertopics/pdq/treatment/unusual-cancers-childhood/HealthProfessional/page6
https://www.wrongdiagnosis.com/s/spitzoid_melanoma/intro.htm
