On 10 May 2007 it was discovered that a patient who was being treated for recurrent endometrial cancer (Paravaginal Tumor) had received a dose which differed from the prescribed dose for the fraction by greater than 50%. The intended dose to the patient was 500 cGy to the tumor. However, the dose was delivered approx 54mm from the tip of the catheter instead of 5 mm from the tip. It was noted in the misadministration report that there were no critical structures that were exposed above any threshold tolerance. Due to a physics catheter measurement error, which was entered into the treatment plan, the catheter did not go in as deeply as intended but stopped short of the target. On audit of the procedure, and remeasurement of the catheter, the chief physicist identified the error in measurement and filed a report with the RI
RCA. Corrective actions in addition to re-measurement and subsequent adjustment of treatment plan included adjustment in the dose per remaining fractions to provide the correct dose to the target.
Rhode Island Report: RI-07-001
Actual initial dose was approximately 10% of expected.
Source Ir-192, 8.05 Curies
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.
- * * UPDATE FROM FLANNERY TO O'HARA VIA E-MAIL AT 0949 ON 7/11/07 * * *
This event (EN43478) has been reviewed and determined to be a reportable medical event.
- * * UPDATE FROM FERRUOLO TO SNYDER VIA FACSIMILIE AT 1452 ON 3/27/08 * * *
The following information was received from the State via facsimilie:
Based on preliminary information obtained per voice and e-mail: underdosing on initial fraction of treatment was due to improper measurement of the catheter. Adjustments were made in subsequent fractions. Written documentation of the incident stated that no critical structures were exposed above the threshold tolerances."
Notified R1DO (Bellamy) and
FSME (McConnell).