Somatic PRKAR1A mutation in sporadic atrial myxoma with cerebral parenchymal metastases: a case report

Atrial myxomas are generally considered benign neoplasms. The majority of tumors are sporadic and less than 10% are associated with an autosomal dominant condition known as the Carney complex, which is most often caused by germline mutation in the gene PRKAR1A. Whether this gene plays a role in the development of sporadic myxomas has been an area of debate, although recent studies have suggested that some fraction of sporadic tumors also carry mutations in PRKARIA. Extra-cardiac complications of atrial myxoma include dissemination of tumor to the brain; however, the dissemination of viable invasive tumor cells is exceedingly rare.

We present here a 48-year-old white woman who developed multiple intracranial hemorrhagic lesions secondary to tumor embolism that progressed to 'false' aneurysm formation and invasion through the vascular wall into brain parenchyma 7 months after resection of an atrial myxoma. Whole exome sequencing of her tumor revealed multiple mutations in PRKAR1A not found in her germline deoxyribonucleic acid (DNA), suggesting that the myxoma in this patient was sporadic.

Our patient illustrates that mutations in PRKAR1A may be found in sporadic lesions. Whether the presence of this mutation affects the clinical behavior of sporadic tumors and increases risk for metastasis is not clear. Regardless, the protein kinase A pathway which is regulated by PRKAR1A represents a possible target for treatment in patients with metastatic cardiac myxomas harboring mutations in the PRKARIA gene.