A young female of Cowden syndrome presenting with Lhermitte-Duclos disease: An illustrative case.

Background: Lhermitte-Duclos Disease (LDD), or dysplastic gangliocytoma, which is a benign hamartomatous condition involving the cerebellum, has a possible association with Cowden syndrome (CS), a rare autosomal dominant disorder due to germline mutations in the phosphatase and tensin homolog (PTEN) tumor-suppressor gene in chromosome 10. Combined CS and LDD cases are rarely reported in the literature. Case Description: We present here a case of a young female patient presented at the emergency department with a severe headache associated with vertigo, vomiting, and cerebellar ataxia. A magnetic resonance imaging scan revealed mixed intensity posterior fossa lesion with almost preserved cerebellar cortical striations. Her facial skin had extensive trichilemmoma. Her symptoms improved after the excision of the posterior fossa lesion through suboccipital craniotomy and histopathology revealed LDD. Conclusion: In a low-resource country where genetic testing for neurosurgical condition is still inadequate, we used the validated Cleveland Clinic Adult Clinical Scoring for PTEN Testing and the patient had an 82-98% chance for a PTEN gene mutation. Finally, she along with her family was adequately counseled and was advised for regular screening and monitoring since it is a premalignant condition where early detection is imperative if any cancer arises in the near future and is now under our follow-up.