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- Presentation
Melanoma in Situ: Ongoing Controversies and New Insights
Description
The session on Melanoma in Situ (MIS) hosted by Alan Halpern highlights the ongoing debates surrounding the diagnosis and management of melanoma. It begins with an overview of the definitions of cancer and precancerous lesions as per the National Cancer Institute (NCI), emphasizing the complexities and misuses of the term "precancer." Halpern introduces different types of melanoma in situ, mainly focusing on Lentigo Maligna and Superficial Spreading Melanoma, detailing their clinical presentations and differences. He discusses the historical evolution of MIS terminology, highlighting how awareness and education have influenced melanoma diagnosis rates. The discussion moves to epidemiology, emphasizing concerns about overdiagnosis, particularly citing that around 90% of MIS cases in men might be overdiagnosed. Factors such as increased detection pressure and technological advancements contribute to this issue, leading to a higher rate of identification of indolent lesions that may not pose a significant risk to patients. Halpern advocates for a reevaluation of treatment strategies, suggesting that surveillance may be appropriate for many indolent lesions rather than aggressive interventions. As he concludes, he underscores the need for further research to distinguish between aggressive and indolent melanomas, setting the stage for ensuing discussions on the complexity of diagnosing and treating MIS.
View moreConclusions
- Melanoma in situ (MIS) is defined as abnormal melanocytes in the epidermis that may develop into cancer.
- The term precancerous can be misleading as it implies all abnormal cells are at risk of becoming cancer, which isn't the case for most melanocytes.
- Lentigo maligna melanoma in situ is a slower-growing melanoma that occurs mainly in older individuals with sun-exposed skin.
- Current diagnostic practices have led to significant overdiagnosis of melanoma in situ, with estimates indicating that up to 90% of some cases may be overdiagnosed.
- Increasing detection capabilities, such as dermoscopy and emerging technologies, have contributed significantly to the identification of smaller and less aggressive lesions.
- The historical classification of lentigo maligna has shifted, now being recognized as a cancer rather than merely a precursor.
- There is a pressing need for further research to determine which melanotic lesions are indolent and which may be aggressive, guiding treatment decisions accordingly.
- The therapeutic landscape for melanoma is changing, with a current trend towards less radical treatment for invasive melanoma and more aggressive management for MIS.
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- Catherine M. Olsen, PhD, Nirmala Pandeya, PhD, Philip S. Rosenberg, PhD. Correspondence to Dr Adewole S Adamson. Department of Internal Medicine (Division of Dermatology), The University of Texas at Austin.