CPT® Code 81323

PTEN (phosphatase and tensin homolog) (eg, Cowden syndrome, PTEN hamartoma tumor syndrome) gene analysis; duplication/deletion variant

The CPT® Code 81323 pertains to the molecular genetic testing of the PTEN (phosphatase and tensin homolog) gene, specifically focusing on the identification of duplication or deletion variants. This testing is crucial for diagnosing PTEN hamartoma tumor syndrome, commonly known as Cowden syndrome, which is an autosomal dominant inherited condition. Individuals who inherit a mutated PTEN gene from one parent are at risk of developing this syndrome. The PTEN gene, located on chromosome 10, encodes a protein that functions as a tumor suppressor, playing a vital role in regulating cell division and maintaining cellular integrity. The PTEN enzyme modifies proteins and lipids by removing phosphate groups, which is essential for controlling cell migration, adhesion to surrounding tissues, and the formation of new blood vessels. Cowden syndrome is characterized by the presence of multiple non-malignant tumors that have a predisposition to become cancerous, particularly in the breast, thyroid, and endometrial tissues. There are over 130 documented mutations of the PTEN gene that can lead to this syndrome, with variations that may involve minor changes in DNA building blocks or significant deletions. The resulting alterations in the PTEN enzyme can lead to defective functionality or complete absence, contributing to tumorigenesis. For comprehensive genetic analysis, full sequence PTEN gene analysis is reported under CPT® Code 81321, while testing for known familial variants is reported with CPT® Code 81322. Notably, three familial variants associated with aggressive breast cancer have been identified, which include -903GA, -975GC, and -1026CA, all linked to poor treatment outcomes. The specific focus of CPT® Code 81323 is on the detection of duplication and deletion variants within the PTEN gene, which is essential for understanding the genetic basis of Cowden syndrome and guiding patient management.