Surgical Expertise Helps Advance Treatments for Pineal Region Tumors
, by Brittany Cordeiro, NCI-CONNECT Program Manager
Dr. Prashant Chittiboina
Read how collaborating across specialties can help neuro-oncologists better understand pineal region tumors.
Each year, an estimated 81 adults are diagnosed with a pineal region tumor in the United States. These tumors are a type of rare central nervous system (CNS) tumor that form in the pineal region of the brain. To better understand these extremely rare tumors, NCI-CONNECT is collaborating with clinicians across disciplines. This includes Prashant Chittiboina, M.D., assistant clinical investigator and neurosurgeon at the National Institutes of Neurologic Disorders and Stroke at NIH.
Dr. Chittiboina joined NIH in 2012 as a fellow, becoming a staff clinician in the Surgical Neurology Branch in 2013. He became an assistant clinical investigator in 2015. He specializes in treating patients with rare pituitary and skull base tumors and complex spinal cord tumors. This includes pineal region tumors and ependymomas in the brainstem and spinal cord.
His laboratory studies neurosurgical disorders of the pituitary gland and disorders arising from inheritable tumor syndromes. His current work is focused on changing the outcomes of neurosurgical disorders through improved imaging.
“It is a very exciting time for my research because of the focus on rare cancers, which are very challenging to accurately diagnose and successfully treat,” says Dr. Chittiboina.
As a pituitary and skull base neurosurgeon, Dr. Chittiboina treats complex and complicated tumors that are often hard to completely remove. He partners with neuro-oncologists, like Mark Gilbert, M.D., chief of the NCI Center for Cancer Research's Neuro-Oncology Branch and co-leader of NCI-CONNECT at NIH, to develop further treatment strategies. What Dr. Chittiboina learns in his clinical practice then informs his research.
Treating Pineal Region Tumors
“Pineal region tumors are a special category of deep tumors of the brain,” explains Dr. Chittiboina. “They are in the skull-base area, so we use specialized surgical techniques to reach and remove the tumors.”
The pineal region is located deep in the middle of the brain. Pineal region tumors arise from cells that form the pineal gland or from the cells of the surrounding tissue. They are grouped in four grades and various subtypes based on their cell of origin and other characteristics.
To treat pineal region tumors, doctors first review the imaging very carefully. “Serial imaging helps us confidently determine if the lesion is a cancerous tumor or benign [non-cancerous] cyst,” says Dr. Chittiboina. If it is a tumor, doctors perform additional testing of blood and spinal fluid to look for markers that may help further plan for treatment.
“Because there are at least six common types of tumors in the pineal region—and within those, 20 different subtypes—the markers are very helpful to determine the correct course of treatment,” explains Dr. Chittiboina. “For example, researchers have discovered six or seven markers that indicate a tumor will respond better to upfront radiation therapy before surgery.”
Pineal region tumors are challenging to remove surgically. They lie in the dead center of the brain, so they are the furthest structure from the surface and hard to reach—no matter the approach. And to complicate matters, the pineal region is surrounded by big blood vessels.
Until the 1950s, pineal region tumors were considered inoperable. Now, as experienced neurosurgeons, we understand how to safely remove the tumors when possible.
In a few benign tumors, if surgery is successful, many patients never need further treatment. Unfortunately, most patients need additional therapies, such as the ones provided by Dr. Gilbert’s team.
There are two main challenges to successfully treating pineal region tumors: removing the tumors safely and treating the remaining tumor or a recurrence effectively.
Partnering to Study Rare Tumors
Dr. Chittiboina and his research team are investigating better methods to diagnose and treat pineal region, skull base, pituitary, and other rare tumors using imaging and molecular data. Their recent research has shown using newer imaging strategies, including a positron emission tomography (PET) scan and special magnetic resonance imaging (MRI), they’re better able to detect the tumors.
The researchers are then using tissue taken during surgery to study the molecular characteristics of the tumor. “The goal is to figure out new ways to attack these rare tumors without hurting normal brain functioning,” says Dr. Chittiboina. “For instance, we may be able to start a drug trial using already approved medications for other cancers based on our findings.”
Dr. Chittiboina is partnering with NCI-CONNECT to care for patients with rare brain and spine tumors. “This is a fruitful time in patient care and research,” says Dr. Chittiboina. “We are collaborating in patient care with Dr. Gilbert and his team to determine the best treatment strategies and services for patients with rare tumors.” Dr. Gilbert is also leading rare brain and spine tumor studies.
This means more patients with these rare tumors will visit the NIH Clinical Center. For pineal region tumors, the increase could be impactful. “The volume of patients will enable our research. We have two new studies opening soon—a surgical imaging study and a drug trial,” says Dr. Chittiboina. “We hope patients will participate because we strive every day to do ground breaking research and focus on what is important to advance our understanding of these cancers and offer patients experienced service.”