Therapy Misadministrations in 2009

Event
Summary A patient undergoing external beam radiation therapy received 5 of 14 fractions to the wrong treatment site. Because of the error an unintended dose of 12.5 Gy was administered to an area 8.5 cm inferior to the intended site.
Root Cause The misalignment of the patient was caused by the misplacement of a tattoo on the patient to mark the location of the beam central axis. The tattoo misplacement was caused by an operator failing to correctly zero the CT simulator's alignment lasers to the radio opaque fiducial markers.
Corrective Action Written procedures were changed and staff instruction was provided to ensure that proper laser alignment was done during the simulation process in the future.
Effect on Patient The facility reviewed the patient dosimetry with regard to the normal tissues unintentionally irradiated and expects no adverse effects in the short or long term related to the five treatments delivered.
Event
Summary A patient undergoing radiation treatment to the thoracic spine received 13.05 Gy to the lower thoracic spine area (T9-L1) instead of the upper thoracic spine area (T1-T4). The patient received 5 fractions using an incorrect setup. During the sixth fraction routing port films were taken and the incorrect set-up was recognized by the radiation therapist and reported to the physician.
Root Cause During the T spine simulation three anterior marks were placed on the patient for alignment purposes with the most superior point to be used as the central beam ray mark. During treatment the patient was incorrectly aligned with the central beam on the center mark.
Corrective Action The facility reinforced source-skin distance checking with the radiation therapists. The process of reviewing simulation pictures and patient marks prior to initial treatment was also reinforced.
Effect on Patient The Radiation Oncologist indicated that the unintended dose to the patient should cause no anticipated short or long term adverse health effects.

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