Overgrowth associated with PIK3CA gene. Next GeneDx [1 gene]

PIK3CA-related overgrowth is a clinical spectrum whose main characteristic is the congenital or early childhood appearance of segmental or focal overgrowth with or without cellular dysplasia. The predominantly affected areas are the brain, extremities (including fingers and toes), trunk (including abdomen and chest), and face, usually in an asymmetric distribution. Generalized brain overgrowth may be accompanied by secondary overgrowth of specific brain structures, leading to ventriculomegaly, among other characteristics. Vascular malformations can be capillary, venous, and, less frequently, arterial or mixed. Lymphatic malformations can be in various locations (internal and/or external) and can cause various clinical problems, such as increased volume, pain, and sometimes localized hemorrhages secondary to trauma. Lipomatous overgrowth can occur ipsilaterally or contralaterally.

The DNA analysis from samples of clinically affected tissues obtains better diagnostic results. The sample should preferably be from a fresh dermal biopsy located in an affected area or a surgical excision of the affected tissue.

Service is of great clinical utility since once a mutation in PIK3CA is confirmed, it is possible to recommend targeted treatment using PI3K inhibitors, such as alpelisib. The indication to administer a biological medication of this type and the decision of which drug to choose is subject to the approvals of the country’s regulatory agencies and the judgment of the patient’s doctor.

Service is indicated in the presence of several of the characteristic clinical signs and, therefore, when the clinical diagnosis is considered, at least, highly probable.