Molecular advances affect melanoma classification, treatment

Molecular Diagnostics and Emerging Therapies in Malignant Melanoma (F014)
1-3 p.m.
Sutton Complex

Research has demonstrated that melanoma subsets can be classified at the molecular level according to their mutations. A Friday session will investigate advances in this research, and explore how they affect therapies. The session will also provide an update about the new cancer staging system.

Presentations during the session will explain advances in molecular studies, molecular tests that can help in the diagnosis of melanoma, the development of targeted therapies, and side effects of targeted therapies and immunotherapy. The Eighth Edition of the American Joint Committee on Cancer (AJCC) Staging Manual will also be reviewed.

Mutations key to analysis
“Current human genome analysis has led us to know there are certain types of melanoma that can be classified according to their mutations,” said Martin Charles Mihm Jr., MD, the session director. “With that as a background, we will also talk about the specific tests that are currently needed by practicing dermatopathologists and dermatologists in the diagnosis of melanoma.”

Molecular tests that are being used in the diagnosis of melanoma will be reviewed, including CGH — comparative genomic hybridization — and FISH — fluorescence in situ hybridization, said Dr. Mihm, professor and director of the Mihm Cutaneous Pathology Consultative Service at Brigham & Women’s Hospital.

The morphology of primary cutaneous melanoma using traditional classification methods and newer molecular studies will be reviewed in one presentation. Those methods have led to more refined classifications of the different types of melanoma, he said.

New definitions, classifications
Another presentation will explain changes in the new edition of the AJCC staging system, which will take effect at the start of 2018. Changes include new definitions for T1, T1a, and T1b classifications, and a separate classification of M4 for brain cancers.

“That is a new approach,” Dr. Mihm said. “There are some other important aspects in the new staging. Mitoses are no longer used in staging. It is not that they are not to be counted, but they are not used in the staging of melanoma.”

Therapy updates
Two other presentations will include updates on targeted therapies and immunotherapy in cutaneous melanoma, as well as side effects from those therapies.

“We will take information from the new classification system and use the molecular studies to explain how the therapies work, what is the survival, and what combination of therapies should be used to get the maximum benefit,” Dr. Mihm said. “We will discuss the side effects in detail so the people will understand what the toxicities are with different combinations of therapies.”

The session will also include an interactive segment with an audience response system where attendees will have an opportunity to answer questions about images, such as whether a melanoma is ulcerated.

“They will leave with the basic knowledge of what therapies can be used, what are their side effects, and when to use them,” Dr. Mihm said. “Furthermore, they will have a better understanding of the new AJCC classification and why the different types of melanoma are subtyped based on the molecular studies.”

Dr. Mihm discussed some of the changes in staging with Dermatology World earlier this year; learn more in “Dermatology gets personal.”

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