Tissue dose estimation after extravasation of 177Lu-DOTATATE

Abstract Background Extravasation of radiopharmaceuticals used for vectorized internal radiotherapy can lead to severe tissue damage (van der Pol et al., Eur J Nucl Med Mol Imaging 44:1234–1243, 2017). Clinical management these extravasations requires the preliminary estimation dose distribution in extravasation area. Data are scarce regarding literature. This work presents a methodology estimating after an occurred September 2017, arm patient during 7.4-GBq infusion Lutathera ® (AAA). Methods A local quantification procedure initially developed renal dosimetry was used. calibration factor determined and verified by phantom study. volume interest its variation time were using 4 whole body (WB) planar acquisitions performed at 2 h ( T 2h ), 5 5h 20 20h 26 26h ) beginning three SPECT/CT thoracic , . For better initial volume, 3 volumes defined on SPECT images 3D activity threshold. Cumulated activities associated absorbed doses D 1 calculated MIRD formalism. Results Volumes estimated threshold V = 1000 mL, =400 =180 mL. evaluated monoexponential fit images. Estimated 2.3 Gy, 4.1 6.8 Gy. Evolution area consistent with effective half-life eff h. Conclusions Rapid permitted thanks knowledge previous accidental extravasation. Lutathera® lymphatic drainage quick 2.3h). lower range deterministic effects far under soft necrosis Thus, no surgical rinse proposed. The did not show any clinical consequence