Event Notification Report for October 05, 2026

AGREEMENT STATE REPORT - MEDICAL EVENT

The following information was provided by the Illinois Emergency Management Agency (the Agency) via phone and email:

"The licensee advised on September 24th, 2026, that a patient was to be administered 0.77 GBq of Y-90 Theraspheres during a planned left hepatic lobe radioembolization treatment. The licensee reported that during administration, the authorized user was unable to deliver the Y-90 dose. Additional information was provided by the licensee on September 25th.

"The licensee reported that multiple dosimeter measurements demonstrated zero activity within the tubing/microcatheter connection and at the patient level and that the only measurable activity remained consistently at approximately 2.3 mRem/hr within the delivery box throughout the procedure. The procedure was aborted and the delivery system disassembled as usual. No contamination was found.

"As a precaution, the patient, delivery tubing, and source vial were sent for PET imaging to assess the location of the activity and exclude any unexpected distribution. PET-CT imaging of the patient indicated no microspheres were administered. However, as the administration had been initiated; this is being reported as an under-dose. The patient was notified following the procedure. The referring physician was to be notified by end of day today. The licensee is continuing their investigation and will submit a written report within 15 days as required."

Illinois Item Number: IL260026

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

AGREEMENT STATE REPORT - MEDICAL EVENT

The following information was provided by the California Department of Public Health, Radiologic Health Branch (RHB) via email:

"On September 24, 2026, a patient with liver cancer was scheduled to receive two vials of Y-90 TheraSpheres at the University of California - Los Angeles (UCLA) Health Ronald Reagan Medical Center Interventional Radiology. The first vial was administered without incident. However, upon initiating administration of the second vial, an immediate leak was detected at the catheter connection hub, followed by retrograde flow from the catheter. The physician typically utilizes a Boston Scientific Direxion microcatheter; however, due to a supply backorder, an alternative microcatheter was used for the procedure. A TheraSphere representative was present during the administration and recorded the leak. A radiation survey confirmed the leak was fully contained with no floor contamination detected. Computed tomography (CT) imaging of the waste container indicates a possible catheter blockage per the treating radiologist. Once the waste decays to background levels, the catheter will be physically inspected to confirm the obstruction. The patient was notified by the treating physician that the second dose was not administered. Following a magnetic resonance imaging (MRI) assessment, a repeat Y-90 treatment may be scheduled for the untreated liver segment if clinically indicated.

"The prescribed dose for 'Segment 2' was 790 Gy (3 GBq vial) and the dose delivered was 771.6 Gy (or 97.7 percent of the prescribed dose).
"The prescribed dose for 'Segment 4' was 597 Gy (3 GBq vial) and the dose delivered was 0 Gy (or 0 percent of the prescribed dose).

"This investigation is still ongoing, a thorough description of all events and corrective actions will be sent to RHB in a 15-day report."

California 5010 number: 092526

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

AGREEMENT STATE REPORT - MEDICAL EVENT

The following is a summary of information provided by the New York City Department of Health, Office of Radiological Health (the Office), via email:

On July 13, 2026, a yttrium-90 (Y-90) TheraSphere therapy procedure at Mount Sinai Medical Center resulted in an underdose to the patient's liver. During the procedure, some activity remained in the delivery system after treatment due to a catheter repositioning issue that paused the flow. The estimated dose delivered was approximately 205 Gy out of a prescribed 400 Gy.

The hospital initially determined the delivered dose was clinically adequate and retroactively updated the written directive to match the actual dose delivered. After further communication with the Office inspector, the hospital revised its assessment, acknowledged that the prescription should not have been changed post-administration, and classified the event as a medical event. A full report was provided to the Bureau on September 23, 2026.

New York City incident number: NY260003

A Medical Event may indicate potential problems in a medical facility's use of radioactive materials. It does not necessarily result in harm to the patient.

AGREEMENT STATE REPORT - DAMAGED GAUGE

The following information was provided by the Texas Department of Health State Services (the Department) via phone and email:

"The licensee notified the Department regarding a stuck shutter on a fixed gauge on a dredge in a channel in Galveston Bay. The gauge is a Berthold S/N LD744-CR, containing a Co-60 source with original activity of 500 mCi as of September 2025. The source S/N is 12550925. The gauge is stuck open, the normal operating position. There is no threat to the general public due to the location of the gauge. Berthold is scheduling a service technician. Further information will be submitted in accordance with SA-300 requirements."

Texas incident number: 10332
Texas NMED number: TX260041