Background: Cowden syndrome is an autosomal dominant disorder characterized by the development of multiple intestinal hamartomas, distinctive mucocutaneous lesions, and an increased risk of endometrial, breast, and thyroid cancer.
Case: An adolescent girl whose mother had a known germline PTEN mutation presented with abnormal vaginal bleeding and was diagnosed with a grade 2 endometrial adenocarcinoma. She underwent a robotic hysterectomy and was found to have no myometrial invasion or distant disease. Genetic testing revealed the patient to have the familial germline PTEN mutation.
Conclusion: The strikingly young age of onset of this patient's endometrial cancer highlights the need for additional study to better understand Cowden syndrome and to determine what endometrial cancer screening and preventive strategies are needed.