This article explores rare brain tumor types, including ganglioglioma, olfactory neuroblastoma, brain stem gliomas, grade III meningioma, and pineoblastoma. It covers their origin, symptoms, and treatment options, emphasizing the importance of accurate diagnosis and management of these uncommon tumors.

Understanding Less Common Brain Tumors

With over 120 known brain tumor subtypes, identifying rare forms can be difficult. This guide highlights some of the most unusual brain tumors.

According to the American Cancer Society, in 2015, more than 22,500 people in the U.S. were diagnosed with primary brain tumors. An estimated 15,000 adults died from complications, and around 4,300 children and teens received diagnoses that year, with over half under age 15.

Brain tumors result from abnormal cell growth within the brain tissue, either benign or malignant. Primary tumors originate within the brain, while secondary (metastatic) tumors spread to the brain from elsewhere. Treatment strategies depend greatly on the tumor's origin. The National Brain Tumor Society recognizes over 120 tumor varieties.

While gliomas are the most common, comprising nearly 45% of primary tumors, many rare types exist. Here are some uncommon brain tumors you might not be familiar with:

Ganglioglioma

Making up about 1% of brain tumors, gangliogliomas are uncommon growths originating from a single cell and are usually benign. Only 10% are malignant. Complete surgical removal is typically required, with additional treatments like radiation or chemotherapy if incomplete removal occurs.

Olfactory Neuroblastoma

Also called esthesioneuroblastoma, this rare tumor starts in the nerve responsible for smell within the nose. Symptoms may include nasal congestion, bleeding, loss of smell, excessive tearing, and nasal discharge. Treatment options include surgery, chemotherapy, and radiation therapy.

Brain Stem Gliomas

These tumors develop at the base of the brain stem, causing symptoms like nausea, facial weakness, vision problems, speech and swallowing difficulties, and limb weakness. Surgery is often not possible; radiation therapy is commonly used.

Grade III Meningioma

Meningiomas originate in the membranes covering the brain and spinal cord. Most are benign (Grade I), but a minority may turn malignant, classified as Grade III. Symptoms can include seizures, headaches, vision changes, and behavioral issues. Treatment usually involves surgery and radiation; chemotherapy is under investigation.

Pineoblastoma

Frequently found in children, pineoblastomas develop in the pineal gland. Factors like RB1 gene mutations may increase risk. Treatment includes surgical removal, followed by chemotherapy and radiation to eradicate residual tumor cells.

Diagnosis typically involves physical exams, neurological assessments, and imaging tests such as CT, MRI, and angiography based on clinical evaluation.