Development of RET mutant cutaneous angiosarcoma during BRAF inhibitor therapy

Area of Science:

• Oncology
• Molecular Biology
• Dermatology

Background:

• BRAF inhibitors are targeted therapies for certain cancers.
• Paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway can occur with BRAF inhibitor treatment.
• This pathway activation is linked to accelerated tumor growth and secondary malignancies like squamous cell carcinomas (SCCs) and keratoacanthomas (KAs).

Observation:

• A patient treated with vemurafenib developed a cutaneous angiosarcoma six months after therapy initiation.
• Next-generation sequencing (NGS) identified a RET mutation upstream of the MAPK pathway in the patient's tumor.
• This suggests BRAF inhibitors may promote the growth of diverse secondary cancers.

Findings:

• BRAF inhibitor therapy can promote the development of secondary malignancies beyond SCCs and KAs.
• RET mutations may play a role in BRAF inhibitor-associated tumorigenesis.
• Angiosarcoma is a potential, albeit rare, secondary malignancy associated with BRAF inhibitors.

Implications:

• Increased physician awareness of the spectrum of secondary malignancies is crucial for early detection and treatment.
• Monitoring patients on BRAF inhibitors for new or unusual tumors is recommended.
• Further research is needed to understand the mechanisms underlying BRAF inhibitor-induced secondary malignancies.