Optic pathway gliomas: neoplasms, not hamartomas.

IMPORTANCE Optic pathway gliomas are an important neuro-ophthalmic cause of vision loss in children. Their management depends on whether they are considered neoplasms or hamartomas. OBJECTIVE To outline the evidence that optic pathway gliomas are slowly growing neoplasms and not hamartomas. DESIGN Review of relevant studies in the literature. SETTING The authors are from a pediatric tertiary referral center. RESULTS The growth patterns and histopathology of optic pathway gliomas are more consistent with those of neoplasms. Spontaneous regression, thought to be a characteristic of hamartomas, can be seen in neoplasms of other types as well as in optic pathway gliomas. Chemotherapy used in low-grade gliomas has been shown to halt or improve vision loss in optic pathway gliomas in many cases. CONCLUSIONS AND RELEVANCE Optic pathway gliomas are not hamartomas but truly are neoplasms. Thus, patients should be followed up closely, and chemotherapies should be used when clinical progression occurs. Other more directed therapies will certainly be used in the future.