By Heriberto Perez–Zuñiga

RIO GRANDE VALLEY, TEXAS – JAN. 15, 2026 – His work happens quietly, behind the scenes, but its impact is felt by every patient who walks into the UT Health RGV Cancer and Surgery Center.

Before a single beam of radiation is delivered and before a patient ever lies down for treatment, Antonio Martinez Jr., medical dosimetrist at UT Health RGV, already has spent hours thinking through every detail.

Martinez studies CT, MRI and PET scans, mapping disease millimeter by millimeter.

"Every plan represents a person," he said. "You want to do this right."

Born and raised in Brownsville, Martinez grew up watching families travel hours away from the Valley to receive specialized cancer care. When his mother-in-law battled cancer, he understood firsthand why bringing advanced care home mattered so much.

NEW PRECISION TECHNOLOGY

On any given day inside the UT Health RGV Cancer and Surgery Center, that new radiation technology, TrueBeam, is preparing to deliver a level of precision previously unavailable in the region.

The machine's sleek robotic arm glides effortlessly around the treatment table, capable of delivering radiation beams from virtually any angle with millimeter precision.

The technology targets tumors with exceptional accuracy, while minimizing radiation exposure to surrounding healthy tissue. It can track tumors that move with breathing, adjusting in real time to keep treatment focused exactly where it's needed. 

BUILDING A FOUNDATION

To enable those patients to receive specialized treatment locally, Martinez plays a vital role as a medical dosimetrist, ensuring that precision becomes reality for each patient.

He is part of the team making that happen by designing radiation treatment plans for some of the most advanced cancer care now available in the region.

Working alongside radiation oncologists, he designs and calculates individualized radiation treatment plans using advanced imaging and planning software.

His goal is to deliver the prescribed dose to the cancer itself, while protecting nearby organs as much as possible.

"Every plan is a balance," he said. "You're thinking about anatomy, imaging, motion and safety, all at once. It's very detail-oriented work, but that's what allows us to deliver this high-quality care."

A primary focus is preparing the program for ASTRO APEx accreditation, a nationally recognized designation for radiation therapy quality and safety.

MEANINGFUL WORK

Martinez, who has been part of the UT MD Anderson School of Health Professions in Houston, University Hospitals in Cleveland, and Texas Oncology in McAllen, is now bringing that knowledge to help build UT Health RGV’s radiation oncology program.

"I've seen how high-level cancer centers operate, I've been part of them," he said. "Our goal here is to bring that same standard of care."

Martinez has nicknamed one of the TrueBeam machines "Eve," after his late mother-in-law, as a reminder of why the work matters.

He remembers the long drives, the waiting rooms far from home, the weight of uncertainty. Now, when he walks past Eve each morning, he thinks about the families who won't have to make those same journeys.

"A cancer center can have the best machine in the world, but it doesn't mean anything without the people operating it," he said. "I'm from the Valley, and being able to use the training I received to support cancer care in my own community means everything to me.  

“Knowing that patients in the Valley can receive high-quality treatment from someone who is from this community? That's what makes the work even more meaningful."