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Published on: March 11, 2021
Implementation of a Multidisciplinary Protocol for the Safe Handling of Iodine-125 Radioactive Seeds in the Pathology
Amanda Rodríguez-Villena1,2, Ute Corina Vera Schmülling3, Irene Vicente Zapata4
1Department of Pathology, Ramón y Cajal University Hospital, Ramón y Cajal Health Research Institute (IRYCIS), Madrid, Spain.
Background:
Iodine-125 radioactive seeds (I125-RS) are increasingly used for preoperative localization of nonpalpable breast lesions due to their precision, safety, and logistical advantages. However, due to radiation safety regulations, their use requires a coordinated and strictly regulated workflow to ensure safe handling and retrieval of radioactive material. This study assesses the first year of a multidisciplinary protocol implemented to standardize I125-RS management and minimize incidents.
Methods:
A protocol involving Radiology, Surgery, Nuclear Medicine, and Pathology was established to ensure proper documentation, transport, radiographic confirmation, seed retrieval, and incident reporting. All I125-RS recovered from formalin-fixed specimens between May 2022 and September 2023 were evaluated. Incidents were classified as protocol deviations (Category I) or technical retrieval difficulties (Category II). Clinicopathological data were collected, and analyses were performed using chi-square and ANOVA tests (p < 0.05).
Results:
A total of 146 seeds were retrieved from 130 specimens from 123 patients. Most samples were lumpectomies (89.2%); 24.4% of patients received neoadjuvant therapy. Invasive carcinoma accounted for 82.3% of diagnoses. Double-seed placement was used in 16 cases. Positive margins occurred in 9.1%, and 7.2% required reoperation. There were 18 incidents (14.6%): Category I, 10 (55.6%), mainly documentation errors or seed displacement within containers; and Category II, 8 (44.4%), mostly seeds hidden within tissue slices. Nuclear Medicine was consulted in 11 cases. Importantly, no seeds were lost. No significant associations were found between incidents and clinicopathological variables.
Conclusions:
The multidisciplinary protocol ensured safe and efficient handling of I125-RS, preventing seed loss and improving traceability. Most incidents were minor, manageable, and reduced with staff training and adherence to standardized procedures. Continuous monitoring supports workflow optimization and maintains safety standards in pathology laboratories. This approach may serve as a model for institutions implementing I125-RS localization.
