SPECT/CT Image-Derived Absorbed Dose to Red Marrow Correlates with Hematologic Toxicity in Patients Treated with [177Lu]Lu-DOTATATE

• DOI: 10.2967/jnumed.123.266843
• Publication Date: 2024-03-28T18:55:14Z
• Authors: Johan Blakkisrud; Avery B. Peterson; Scott J. Wildermann; Griffen Kingkiner; Ka Kit Wong; Chang Wang; Kirk A. Frey; Caroline Stokke; Yuni K. Dewaraja
• Keywords: Radionuclide therapy

Hematologic toxicity, although often transient, is the most common limiting adverse effect during somatostatin peptide receptor radionuclide therapy. This study investigated association between Monte Carlo–derived absorbed dose to red marrow (RM) and hematologic toxicity in patients being treated for their neuroendocrine tumors. <b>Methods:</b> Twenty each receiving 4 treatment cycles of [¹⁷⁷Lu]Lu-DOTATATE were included. Multiple-time-point ¹⁷⁷Lu SPECT/CT imaging–based RM dosimetry was performed using an artificial intelligence–driven workflow segment vertebral spongiosa within field view (FOV). coupled with in-house macroscale/microscale Carlo code that incorporates a microstructure model. Absorbed estimates lumbar thoracic vertebrae FOV, considered as representations whole-body dose, correlated markers at about 8 wk after cycle 3- 6-mo follow-up completion all cycles. <b>Results:</b> The median FOV (<i>D</i>_{median,vertebrae}) ranged from 0.019 0.11 Gy/GBq. cumulative across 1.3 Gy (range, 0.6–2.5 Gy). generally mild, no grade 2 or higher platelets, neutrophils, hemoglobin. However, there decline blood counts over time, fractional value relative baseline 6 mo 74%, 97%, 57%, lymphocytes, hemoglobin, respectively. Statistically significant correlations found subset doses, both follow-up. included correlation platelet count follow up: <i>D</i>_{median,vertebrae} (<i>r</i> = −0.64, <i>P</i> 0.015), <i>D</i>_{median,lumbar} −0.72, 0.0038), <i>D</i>_{median,thoracic} −0.58, 0.029), <i>D</i>_{average,vertebrae} −0.66, 0.010), where are vertebrae, respectively, mass-weighted average vertebrae. <b>Conclusion:</b> image-derived including reduction platelets up. These findings indicate can potentially be used understand manage