ASTRO 2026: Dr. Nitin Ohri Evaluates Radiation and Systemic Combo Toxicities

At the American Society for Radiation Oncology (ASTRO) 2026 Annual Meeting, thoracic and gastrointestinal radiation oncology experts addressed safety standards when combining radiation therapy with systemic treatment regimens.

In an on-site interview with Oncology Nursing News, Nitin Ohri, MD, MS, Professor of Radiation Oncology at Montefiore Einstein and Albert Einstein College of Medicine in the Bronx, New York, highlighted essential clinical considerations for monitoring treatment toxicities in multimodal cancer care.

As novel targeted agents, immunotherapies, and chemotherapy regimens are increasingly integrated alongside radiation protocols, oncology nurses and advanced practice providers (APPs) play a crucial role in early adverse event detection.

Key Takeaways for Oncology Nursing Practice

• Vigilant Toxicity Screening: Combining radiation therapy with systemic agents requires close monitoring to differentiate baseline toxicities from compounded adverse events.

• Additive vs Synergistic Risk Profiles: Most combination regimens produce additive toxicities, but specific drug-radiation interactions can trigger severe, multiplicative reactions.
• Protocol-Driven Trial Oversight: Novel combination regimens should be administered within prospective clinical trials to ensure standardized safety monitoring.
• Proactive Symptom Management: Oncology nurses must maintain heightened surveillance for overlapping organ toxicities, such as pneumonitis and esophagitis.
• Evaluating Additive Versus Synergistic Combination Toxicities
  Combining radiotherapy with systemic antineoplastic therapies offers substantial efficacy but requires clinical surveillance.

Ohri explained that evaluating patient safety begins with assessing whether overlapping toxicities remain predictable or escalate exponentially.

"As we combine radiation with different systemic therapy regimens, we are always looking very carefully to ensure that there's no synergistic or multiplicative toxicities," Ohri stated.

Distinguishing between additive side effects—where each modality independently contributes known toxicities—and true synergistic amplification is critical for oncology care teams.

"My take on the data thus far is that yes, systemic therapy has some risks and radiation may have some risks," Ohri noted. "But when you combine the two, generally those risks are sort of additive."

Mitigating High-Risk Interactions Through Clinical Trial Oversight

While many combination protocols maintain manageable safety profiles, certain drug classes interact unpredictably with radiation, triggering acute organ injury. Ohri cautioned that specific agent combinations demand heightened vigilance.

"There are certain cases and certain drugs where radiation in combination with those drugs can cause major major problems in sort of a synergistic fashion," Ohri warned. To protect patient safety, Ohri emphasized evaluating non-standard combinations within structured investigational frameworks.

These insights underscore the necessity for oncology nurses to adhere strictly to clinical trial protocols, document early adverse events, and maintain interprofessional communication during multimodality therapy.