Bilateral dysplastic gangliocytoma with concurrent polyostotic fibrous dysplasia: a case report and literature review

Background: Dysplastic gangliocytoma is a sporadic cerebellar benign tumor with the characteristics of hamartoma and true tumor, also known as Lhermitte-Duclos 's disease. Bone fibrous dysplasia is a slowly progressive self-limited benign bone tissue disease. Cowden syndrome, an autosomal dominant genetic disorder caused by germline mutations in the PTEN gene, is considered to be closely related to dysplastic gangliocytoma. McCune-Albright syndrome is a disease characterized by café-au-lait skin macules, polyostotic FD, and precocious puberty. The etiological mechanism of both conditions is not yet clear. We report a rare case of bilateral dysplastic gangliocytoma with concurrent polyostotic fibrous dysplasia.

Case description: We describe a 16-year-old male teenager with both LDD and FD diseases. He came to our hospital for medical examination because of headaches and poor eyesight. MRI revealed the proliferation of the skull and abnormal signals in the cerebellum, as well as supratentorial hydrocephalus. Subtotal resection of the cerebellar tumor was performed, and the diagnosis of LDD and FD was confirmed by histopathology. No other abnormal changes were found in systemic medical examination, no PTEN gene mutation was found in the genetic analysis, so the diagnosis of Cowden syndrome and McCune-Albright syndrome were excluded.

Conclusion: LDD and FD are two rare diseases, and the simultaneous occurrence of the two conditions has not been reported before. Our report challenges the etiology of the two diseases and the relationship between them, hoping to provide a reference for the study of the two diseases.

Keywords: Cowden syndrome; Dysplastic gangliocytoma; Fibrous dysplasia; Lhermitte-Duclos disease; McCune-Albright syndrome.