ABSTRACT
Background: Primary intracranial germ cell tumors (ICGCT) are often diagnosed with tumor markers and imaging, which may avoid the need for a biopsy. An intracranial germ cell tumor with mild elevation of markers is seldom stratified as a distinct entity. Methods: Fifty-nine patients were stratified into three groups: pure germinoma (PG), secreting germinoma (SG) and non-germinomatous germ cell tumors (NGGCTs). Results: At 5 years, progression-free survival and overall survival of the three groups (PG vs SG vs NGGCT) were 91% versus 81% versus 59%, and 100% versus 82% versus 68%, respectively. There was no statistically significant difference in outcome among histologically and clinically diagnosed germinomas. Conclusion: A criterion for clinical diagnosis when a biopsy is not feasible is elucidated, and comparable outcomes were demonstrated with histologically diagnosed germinomas.
Lay abstract Intracranial germ cell tumors (ICGCTs) are rare brain tumors, which often require markers in blood or cerebrospinal fluid, imaging and a tissue biopsy to establish a diagnosis. However, when tissue sampling is not possible, tumor markers can sometimes be used to diagnose ICGCTs. The authors propose guidelines for a diagnosis and a novel subtype of ICGCT called secreting germinoma, which is also described. Fifty-nine patients were separated into three groups: pure germinoma (PG), secreting germinoma (SG) and non-germinomatous germ cell tumors (NGGCTs). At 5 years, progression-free survival and overall survival of the three groups (PG vs SG vs NGGCT) were 91% versus 81% versus 59%, and 100% versus 82% versus 68%, respectively. There was no significant difference in outcome among tumors diagnosed with markers in blood or cerebrospinal fluid and those diagnosed with a biopsy. The proposed guidelines for diagnosis need to be evaluated in future studies. SGs may not warrant aggressive treatment protocols as used in NGGCT, and their outcome as a distinct group needs to be explored in future studies.
