Meningioma Surgery and Radiosurgery in Central America: A Hybrid Approach Focused on Tumor Control and Neurological Preservation

Meningiomas are often benign tumors, but “benign” does not necessarily mean simple. Their importance depends greatly on where they grow. A small meningioma near the optic nerves, cavernous sinus, brainstem, cranial nerves or major blood vessels may present a greater surgical challenge than a much larger tumor in a safer location.

For nearly two decades, my approach to meningioma and skull-base tumor surgery in El Salvador has increasingly centered on one principle: the objective is not simply to remove the greatest possible amount of tumor, but to achieve durable tumor control while minimizing the neurological price paid by the patient.

That philosophy has led naturally to the integration of microsurgery and stereotactic radiosurgery, particularly for complex skull-base meningiomas.

When complete removal is not necessarily the safest operation

For many accessible meningiomas, complete microsurgical removal remains an excellent treatment and can be curative. But the situation changes when a tumor surrounds a cranial nerve, extends into the cavernous sinus, adheres to the brainstem, involves major arteries or grows immediately adjacent to the optic apparatus.

In those situations, aggressive pursuit of every visible millimeter of tumor may increase the risk of permanent neurological deficit.

Our philosophy is therefore individualized.

Sometimes the best treatment is surgery alone.

Sometimes radiosurgery alone is appropriate.

And in selected complex tumors, the safest strategy may be hybrid treatment: microsurgical decompression of the brain, optic pathways or cranial nerves, followed by stereotactic radiosurgery to the residual tumor.

The purpose of this strategy is deliberate. Surgery addresses the component producing compression and creates space around vulnerable neurological structures. Radiosurgery can then treat tumor deliberately left behind in locations where radical surgical removal would carry disproportionate risk.

In this setting, leaving residual tumor is not necessarily failure to complete an operation. It may be the planned endpoint of a safer operation.

Surgery and radiosurgery are not competing treatments

One of the most important changes in modern skull-base surgery has been moving away from the idea that surgery and radiosurgery must compete.

They solve different problems.

Microsurgery provides immediate decompression, tissue diagnosis when required, and relief of mass effect.

Radiosurgery provides a non-invasive method of controlling small or moderate volumes of residual or selected primary tumor with high geometric precision.

For a patient with a complex meningioma, the relevant question is therefore not simply:

“Can this tumor be removed?”

The better question is:

“What combination of treatment provides the greatest probability of long-term tumor control while preserving vision, eye movement, facial sensation, hearing, swallowing, brainstem function and quality of life?”

That distinction is particularly important in skull-base and cavernous sinus meningiomas.

Published radiosurgical experience with meningiomas in Central America

Our clinical experience has also generated peer-reviewed evidence from Central America.

In 2021, our group published Multiplatform Radiosurgery for Intracranial Meningiomas and Dose to the Dural Tail in Cureus. The study reviewed 143 patients with presumed or histologically confirmed WHO Grade I meningiomas treated between 2011 and 2020 with different radiosurgical platforms. Among patients with adequate follow-up, overall tumor control was 96% at a median follow-up of approximately three years.

An important question addressed by that study was whether the characteristic dural tail of a meningioma needs to receive the full prescription dose. Although tumor cells can extend into portions of the dural tail, our results did not demonstrate improved tumor control from deliberately pursuing the entire radiological tail with the prescription dose during the available follow-up.

That observation is clinically relevant because radiosurgery is always a balance: sufficient dose must reach the tumor while unnecessary irradiation of surrounding brain, nerves and vessels should be minimized.

Cavernous sinus meningiomas: protecting vision and cranial nerves

The cavernous sinus represents one of the most challenging regions in skull-base neurosurgery. It contains the internal carotid artery as well as cranial nerves responsible for eye movement and facial sensation, and it lies immediately adjacent to the optic pathways.

In 2022, our group published Visual Symptoms Outcomes in Cavernous Sinus Radiosurgery and a Systematic Review. The series included *58 patients with benign tumors involving the cavernous sinus, including *31 meningiomas and 27 pituitary adenomas, treated between 2011 and 2021. Twenty-six had undergone previous surgery, while 32 received radiosurgery as their initial treatment.

At a median follow-up of 33 months, the study reported *100% radiological tumor control in the overall cohort, while *51.7% of patients with visual or ocular motor symptoms improved. No patient experienced new loss of visual acuity or visual-field deficit at the last reported follow-up.

These results reinforce an important principle in selected cavernous sinus tumors: the objective is not merely to control the image on MRI. It is to control the tumor while preserving the nerves passing through one of the most anatomically unforgiving regions of the skull base.

Nearly two decades of surgical experience

The published studies represent only part of the clinical experience.

For close to 20 years, I have operated on benign brain tumors, meningiomas and skull-base tumors in El Salvador. That accumulated surgical experience has progressively changed my own definition of a successful operation.

Early in a surgical career, complete removal can appear to be the ultimate measure of technical success.

Experience teaches a more nuanced lesson.

A radiologically perfect resection accompanied by a permanent cranial nerve deficit may not represent the best possible outcome for that patient. Conversely, a carefully planned subtotal resection followed by radiosurgery may preserve neurological function while providing durable tumor control.

The operation must therefore be designed around the patient, not the MRI.

The hybrid philosophy: decompress what must be decompressed, control what does not need to be removed

This is the principle that increasingly guides our management of selected complex meningiomas:

Decompress what threatens neurological function. Preserve what should not be injured. Use radiosurgery to control tumor that does not need to be removed surgically.

For a skull-base meningioma surrounding cranial nerves or major vessels, this may mean opening the surgical corridor, decompressing the optic nerve or brainstem, obtaining pathological diagnosis when necessary, and deliberately leaving tumor where further dissection would substantially increase neurological risk.

The residual component can then be evaluated for stereotactic radiosurgery.

This is not appropriate for every meningioma. Tumor size, location, histology, growth pattern, edema, symptoms, age, previous treatment and proximity to radiation-sensitive structures all influence the decision.

But when properly selected, hybrid surgery and radiosurgery transform the goal from maximal anatomical removal to maximal therapeutic benefit.

Which meningiomas may be considered for radiosurgery?

Stereotactic radiosurgery is commonly considered for selected small- to medium-sized presumed WHO Grade I meningiomas, residual tumor after surgery, recurrent meningioma, and tumors in surgically challenging locations such as the cavernous sinus or skull base. Treatment selection must account for tumor volume and proximity to critical structures, particularly the optic nerves and chiasm.

Larger tumors producing substantial mass effect often require surgical decompression first. In those cases, radiosurgery may become complementary rather than primary treatment.

That is precisely why access to both surgery and radiosurgery within the same clinical strategy matters.

A Central American experience built around preservation

Advanced skull-base and radiosurgical care is frequently associated with major centers in North America, Europe or Asia. Our experience has been developed in San Salvador, El Salvador, with radiosurgical work extending through programs in Central America.

The importance of that experience is not geographical pride. It is evidence that sophisticated decision-making for complex brain tumors can be developed within our region.

Our two published Cureus studies provide peer-reviewed documentation of radiosurgical experience with intracranial meningiomas and benign cavernous sinus tumors from Central America.

But the larger philosophy comes from years spent on both sides of the treatment decision—as a surgeon who can operate on the tumor and as a radiosurgeon who can sometimes choose not to remove the portion that does not need to be removed.

That changes the question.

The objective is no longer to prove how much tumor we can take out.

The objective is to control the disease while leaving the patient with as much normal neurological function as possible.