[Muir-Torre syndrome with previously undescribed frameshift mutation in the MSH2 gene]

Area of Science:

• Oncology
• Genetics
• Dermatology

Background:

• Muir-Torre syndrome (MTS) is a rare variant of hereditary non-polyposis colorectal carcinoma (Lynch syndrome).
• MTS is characterized by visceral carcinomas and distinct skin tumors, including keratoacanthomas and sebaceous gland neoplasms.
• Early diagnosis is crucial as tumors are typically diagnosed around age 53.

Observation:

• A 65-year-old male patient presented with clinical features suggestive of Muir-Torre syndrome.
• The patient exhibited multiple skin tumors, including those characteristic of sebaceous differentiation.
• Diagnostic investigations were pursued to identify the underlying genetic cause.

Findings:

• Molecular genetic testing identified a novel mutation within the MSH2 gene.
• This mutation resulted in a frame shift, disrupting the normal function of the MSH2 gene.
• The MSH2 gene is critical for DNA mismatch repair and is frequently implicated in Lynch syndrome and MTS.

Implications:

• This case highlights the importance of genetic testing in diagnosing rare conditions like Muir-Torre syndrome.
• Identification of novel mutations expands our understanding of the genetic basis of MTS and Lynch syndrome.
• Understanding these mutations can lead to improved genetic counseling and personalized cancer surveillance strategies for affected families.