LITT: Prolonging life, limiting complications in recurrent medulloblastoma

CHOC’s multidisciplinary team used laser interstitial thermal therapy (LITT) — one of several minimally invasive treatments shaping the present and future of pediatric neuro-oncology and pediatric neurosurgery — to treat recurrent medulloblastoma in a young patient as an alternative to standard-of-care surgical resection. A year after the procedure, the patient showed significant reduction in tumor size and enhancement.

“Up to 30% of patients have recurrence of medulloblastoma,” says Dr. Chenue Abongwa, pediatric neuro-oncologist at the Hyundai Cancer Institute at CHOC. “In those situations, less than 25% survive, which is a challenge because we are always looking for ways to improve treatment for patients with recurrent disease who have undergone extensive treatment and are dealing with complications of treatment.”

The benefits of laser ablation

While the outlook for medulloblastoma is bleak — survival rates have stagnated in the last two decades, while survivors tend to have poor quality of life — LITT holds out hope for both prolonged survival and improved outcomes. The procedure is still relatively rare, but increasingly, clinicians are turning to LITT to treat certain recurrent medulloblastomas and similar malignancies. Ideal candidates include patients with small — a circumference of 3 centimeters or less — focal lesions situated deep in the brain for whom resection via craniotomy is not optimal or desirable.

“With LITT, we make a small, 5-millimeter incision and stereotactically insert a probe to the location of the lesion,” says Dr. Joffre Olaya, pediatric neurosurgeon at the CHOC Neuroscience Institute. “We use a laser to ablate the tumor under direct MRI visualization. Ablating the tumor is comparable to resecting it, but without having to perform a craniotomy.”

A robotic stereotactic assistance device allows pediatric neurosurgeons to precisely target tumors without damaging surrounding brain tissue or vasculature. Typically, the surgeon will conduct a concurrent biopsy of the tumor.

“Our patients have tolerated LITT quite well,” Dr. Olaya says. “Most return home the day after the procedure and have minimal pain. Recovery is much quicker than with a standard craniotomy.”

Dr. Olaya also values the flexibility that LITT affords.

“LITT does not eliminate the option of standard resection,” he says. “If a tumor continues to grow or spread after a patient undergoes LITT, we can always go back and perform a standard craniotomy.”

LITT for a patient with recurrent medulloblastoma and posterior fossa syndrome

Dr. Abongwa and Dr. Olaya were part of a multidisciplinary team that used LITT to treat an 11-year-old patient who developed posterior fossa syndrome after undergoing initial medulloblastoma treatment — consisting of gross total resection followed by chemotherapy and radiation therapy — years earlier and had a recurrence of the brain tumor.

“This case is an excellent illustration of when we can use laser ablation,” Dr. Abongwa says. “The patient had undergone standard treatment for medulloblastoma at age 5, developed significant complications as a result, then had a recurrence. Surgery was not a good option because the family was worried about the patient’s quality of life and the potential for more problems after another craniotomy.”

As with all pediatric brain tumor cases at CHOC, the case was presented to the biweekly neuro-oncology tumor board comprised of pediatric neurosurgeons, pediatric neuroradiologists, a pediatric neuro-oncologist, pediatric neurologists and pediatric endocrinologists. The group discussed the patient’s case and determined LITT would be appropriate.

“We evaluated the patient based on their situation and found that LITT would be a good option to help us control the tumor locally without increasing the chances of the patient experiencing problems related to treatment,” Dr. Abongwa says. “The patient tolerated the treatment well.”

After undergoing LITT, the patient began receiving standard chemotherapy treatment for tumor control. That regimen continues, but after a year of surveillance, no signs of tumor recurrence have emerged.

“LITT offers a less invasive method that may serve as an adjunct in treating recurrent tumors, or, potentially, as palliation,” Dr. Olaya says. “Some patients have recurrent tumors that cause symptoms, but we may not want to put them through an initial major surgery. From a palliative standpoint, LITT may help improve their quality of life and extend life in these situations without having to put these children through a craniotomy.” 

Growing applications

Clinicians need more long-term follow-up data for patients treated with LITT. That is why CHOC is participating in Laser Ablation of Abnormal Neurological Tissue Using Robotic Neuroblate System (LAANTERN), a prospective, multicenter registry that collects safety, quality of life, and outcomes and survival data on up to 1,000 patients for up to five years. This data will help clinicians better understand the efficacy of LITT compared with standard treatment.

Recent research supports the use of LITT to treat newly diagnosed tumors, such as low-grade gliomas, according to Dr. Abongwa, but data from large clinical trials are necessary to justify widespread adoption. In the meantime, CHOC continues to seek ways to enhance patient care.

“CHOC is dynamic,” Dr. Abongwa says. “We are always trying to improve the care of children by offering standard treatments and new, innovative therapies that can improve the chance of a cure.” 

Learn more about the Neuro-oncology Treatment Program.

Personalized medicine, surgical innovations advance pediatric brain tumor care

The Neuro-Oncology Treatment Program at the Hyundai Cancer Institute at CHOC is doing more than providing the most advanced care for pediatric brain tumors — it’s also helping to shape the future of personalized medicine and surgical innovations.

CHOC offers a full range of standard treatments for brain tumors, as well as personalized therapies for many tumor types, such as medulloblastomas, based on genetic subtyping. Experimental treatments are available through Children’s Oncology Group and other consortium and industry-driven clinical trials. Some of these studies — including a trial developed by a CHOC neuro-oncologist to investigate a vaccine for diffuse intrinsic pontine glioma — are part of CHOC’s robust early-phase clinical trials program, according to Dr. Chenue Abongwa, pediatric neuro-oncologist at CHOC.

Dr. Chenue Abongwa
Dr. Chenue Abongwa, pediatric neuro-oncologist at CHOC

CHOC also partners with some of the country’s foremost healthcare institutions, including Mayo Clinic, to apply the latest genomic sequencing and molecular studies in studying each individual tumor.

When a patient presents with a brain tumor, a wide range of specialists are involved from the beginning. “We have a multidisciplinary neuro-oncology tumor board that includes neurologists, neurosurgeons, neuroradiologists, radiation oncologists, pathologists and a neuro-oncologist, and we involve other specialists as needed,” says Dr. Abongwa. “This expertise allows us to select the treatment likely to be the best option for each child while minimizing the risk of side effects.”

Each patient at CHOC is treated via an individualized, precision medicine approach. When surgery is necessary, CHOC has four highly experienced, board-certified pediatric neurosurgeons who can apply some of the most advanced surgical capabilities. “We have the latest in surgical navigation, and we partner with neurologists at CHOC to offer surgical neuromonitoring to track certain nerve potentials during resections,” says Dr. Suresh Magge, medical director of neurosurgery at CHOC and co-medical director of the CHOC Neuroscience Institute. “If we’re operating near the brain stem, it’s important to know if there’s potential for damage in surrounding structures.”

Dr. Suresh Magge
Dr. Suresh Magge, medical director of neurosurgery at CHOC and co-medical director of the CHOC Neuroscience Institute

Several of the surgical therapies CHOC offers are minimally invasive alternatives to craniotomy. One example is endoscopic surgery, which may be appropriate for tumors located in the ventricles. Neurosurgeons can visualize and resect these tumors using an endoscope inserted through a small incision.

“Certain tumors, especially those located deep in the brain, are amenable to laser interstitial thermal therapy (laser ablation),” Dr. Magge says. “This has revolutionized the treatment of certain types of lesions. We can insert a catheter through a small incision down to the deep part of the brain and ablate the tumor without harming surrounding structures. A ROSA™ (robotic stereotactic assistance) robot allows us to insert the laser with a high degree of precision. Patients experience minimal blood loss and typically go home within a day.”

Once treatment concludes, patients ultimately enter the Neuro-Oncology Treatment Program’s longstanding late effects program. This multidisciplinary program provides long-term follow-up of patients and connects them with specialists who can treat endocrine, neurocognitive, psychosocial and other side effects of treatment.

“For some tumors, such as medulloblastomas, we’ve reached the point where we’re achieving good rates of cure, as high as 80% or more,” Dr. Abongwa says. “So now we’re focused on minimizing the long-term effects of treatment. Most institutions don’t have a strong, long-term follow-up program for pediatric patients. Over time, our program has become quite robust and multidisciplinary. That’s another area of benefit that we offer our patients. We’re a child- and family-focused institution. That focus is evident in all the programs and services that are available to our patients.”

Our Care and Commitment to Children Has Been Recognized

CHOC Hospital was named one of the nation’s best children’s hospitals by U.S. News & World Report in its 2020-21 Best Children’s Hospitals rankings and ranked in the cancer specialty.

Learn how CHOC’s pediatric oncology treatments, expertise and support programs preserve childhood for children in Orange County, Calif., and beyond.

In the Spotlight: Chenue Abongwa, M.D.

Chenue Abongwa, M.D., joined CHOC in October 2018 as a pediatric neuro-oncologist at the Hyundai Cancer Institute. After finishing medical school at the Universite de Yaounde in Cameroon, he completed his pediatrics residency at Brookdale University Hospital in New York, his pediatric hematology/oncology fellowship at University of Iowa Hospitals and his neuro-oncology fellowship at Children’s Hospital of Los Angeles. We chatted with him about his time at CHOC so far.

Dr. Chenue Abongwa, Pediatric Neuro-Oncology

What drew you to medicine? Pediatrics specifically?

I was drawn to medicine earlier in my childhood. My mother worked as a nurse, and I often accompanied her when she did house calls to visit children and was very impressed by her dedication and desire to help sick children. I wanted to be like her when I grew up.

What about CHOC stuck out to you?

I initially heard about CHOC in 2013 when I was a fellow in pediatric hematology/oncology and came across a well-written web guideline on febrile neutropenia. This prompted me to seek information about the institution and about the team. I was very impressed by the institutional vision, dynamism, patient-centeredness and search for excellence. I applied without hesitation when the opportunity came.

Are you or do you plan to be involved with any special projects or groups at CHOC?

I am currently involved in several divisional clinical projects based on COG (Children’s Oncology Group) and will be joining some committees.

Can you share some of your goals at CHOC?

My goals are to initially build a strong clinical base by working in the neuro-oncology team in the short term. I hope in the long term to be actively involved in quality improvement, research and teaching.

What do you want your patients and their families to know about CHOC? 

The diagnosis of cancer in a child is a very difficult and traumatic experience to children and their families. Being part of their lives in these extremely difficult periods and advocating for these families is a great privilege. Our team here at CHOC, with its focus on patient-centered care, is the right place for these families to be during this time.

What do you like to do outside of CHOC?

I love traveling, watching football and playing chess.