The symptoms of a craniopharyngioma are caused by compression the growing tumor exerts on surrounding brain structures in the sella and parasellar region. Compression of the pituitary stalk may result in pituitary hormone deficiency that contributes to developmental delay, short stature, obesity, and a range of other hormonal problems including the inability to regulate water balance. Compression of the optic nerves may lead to visual deficits, usually a bitemporal hemianopsia. Larger tumors can cause headache and nausea because of increased intracranial pressure caused by the mass of the tumor in the brain or from a backup of the cerebrospinal fluid that surrounds the brain and spinal cord.
The diagnosis of a craniopharyngioma is based on your symptoms, physical exam and specialized testing including an endocrine and ophthalmic assessment. For an endocrine assessment, special blood tests determine your hormone levels. An ophthalmologist may examine your eyes and perform a visual field test to determine if the tumor is affecting your visual acuity or impairs your peripheral vision.
Imaging studies are also an important component of the diagnosis of craniopharyngiomas. Magnetic resonance imaging (MRI) and Computed tomography (CT) scans are often used. The scan is usually performed with a contrast dye that makes the border and details of the tumor more visible in relation to the surrounding normal brain. The scan also provides detail information regarding the exact size, location and other structures involved by the tumor. In some cases, neurological surgeons may employ an MRI or CT scan with frameless stereotactic guidance for preoperative planning purposes. For this study, a high-resolution contrast MRI or CT is performed and then processed by a computer to create a three-dimensional model of the brain and skull base. This can be used in the operating room when performing endoscopic minimally invasive skull base surgery.
Minimally invasive endoscopic surgery for craniopharyngiomas are usually performed through the sinuses with an endoscope together with an ENT surgeon that specializes in skull base surgery. The ENT specialist may evaluate your particular anatomy before surgery and perform endoscopy of the sinuses.
The initial treatment for a craniopharyngioma usually is surgery to remove as much of the tumor as safely possible. Surgery to remove these tumors can be performed using endoscopic or minimally-invasive skull base techniques or with Traditional or open skull base techniques depending on the exact location and extent of your particular tumor. Because craniopharyngiomas can be adherent to structures within the suprasellar space at the skull base complete resection is often difficult. If hydrocephalus is present because of the tumor, a shunt may be placed during surgery to help drain excess cerebrospinal fluid away from the brain. Even in cases of total resection, these tumors have a tendency towards recurrence, therefore surveillance repeat MRI or CT scans are conducted for a period of time following initial treatment.
Radiation therapy may be used as a follow-up treatment after surgery, especially in cases with residual tumor. In children younger than age 3, radiation therapy may be delayed by the use of surgery or hormone therapies. In addition, non-invasive, stereotactic radiosurgery (CyberKnife and Gamma Knife) may be used as adjunct treatment for small or residual tumors in difficult to reach locations or in patients that have had recurrence. Stereotactic Radiosurgery uses numerous finely focused beams of radiation to accurately target the tumor and while minimizing the effects to any surrounding tissue. The target tumor is usually outlined on a 3-Dimensional model of the brain by the neurosurgeon and the radiation oncologist prior to the procedure.
After surgery, each patient is reviewed at our Multi-Disciplinary Tumor Board with an expert team of neuro-oncologists, medical oncologists, neuro-pathologists, neuro-radiologists and neurosurgeons. Together the tumor board recommends the best treatment options for each patient, incorporating ongoing national clinical trials and the latest treatment protocols.