Endodermal sinus tumor of the pineal region: case report

Area of Science:

• Pediatric Oncology
• Neuro-oncology
• Pathology of Germ Cell Tumors

Background:

• Endodermal sinus tumors, a type of germ cell tumor, typically arise in gonadal tissues.
• These tumors are characterized by yolk sac endoderm and extraembryonic mesoblast overgrowth.
• Extragonadal germ cell tumors are rare, particularly in the pineal region.

Observation:

• A case report of a 12-year-old Caucasian boy with an endodermal sinus tumor in the pineal region is presented.
• This represents the ninth documented case of this tumor in the pineal region globally.
• The tumor's location in the posterior third ventricle highlights similarities between pineal and gonadal germ cell tumors.

Findings:

• The pineal region germ cell tumor histologically mirrors gonadal germ cell tumors.
• A primitive streak disturbance is hypothesized to cause midline extragonadal tumor locations.
• The patient received a treatment regimen including vincristine, actinomycin D, cyclophosphamide, and cobalt irradiation.

Implications:

• The combination chemotherapy and irradiation regimen demonstrated superior efficacy compared to historical treatments like irradiation alone for pineal endodermal sinus tumors.
• This case contributes to understanding the pathology and treatment of rare extragonadal germ cell tumors.
• Further research into the etiology of primitive streak disturbances may elucidate the origins of midline extragonadal tumors.