Radium-223-Dichloride (Ra-223) is an alpha-emitter, used to treat bone metastases. Patients with high metastatic burden and/or with increased trabecular bone uptake could present a higher incidence of hematologic toxicity. We hypothesized that these two factors are predictors of bone marrow failure.
A computer algorithm discriminated between trabecular bone (BVol) and tumor metastases (MVol) within pretherapeutic whole-body skeletal SPECT/CT (N= 47). The program calculated the metastatic invasion percent (INV%) as theMVol/(MVol+BVol) ratio and extracted theBVolmean counts.BVolcounts were correlated to % drop of hemoglobin (Hb), leukocytes (WBC), and platelets (PLT) after 3/6 Ra-223 cycles. Patient-specific and computational-derived parameters were tested as predictors of hematologic toxicity with MANOVA.
B Vol counts correlated with drop of Hb (R= 0,65,p< 0.01) and PLT (R= 0,45,p< 0.01). AppendicularBVolcounts showed a better correlation (p< 0.05,p< 0.01, andp< 0.001 for Hb, WBC, and PLT, resp.). INV% directly correlated withBVolcounts (R= 0.68,p< 0.001). At MANOVA, grade III/IV toxicity was predicted by INV% (p< 0.01), by long-bone invasion (p< 0.005), and byBVolcounts (p< 0.05).
In patients with significant bone tumor burden, degree of bone invasion and trabecular bone uptake are predictors of subsequent bone marrow failure.
BioMed research international. 2017 Dec 25 [Epub]
Francesco Fiz, Samine Sahbai, Cristina Campi, Matthias Weissinger, Helmut Dittmann, Cecilia Marini, Michele Piana, Gianmario Sambuceti, Christian la Fougère
Nuclear Medicine Unit, Department of Radiology, University of Tübingen, Tübingen, Germany., Nuclear Medicine Unit, "Henri Mondor" University Hospital, Paris, France., National Council of Research-SPIN, Section of Genoa, Genova, Italy., National Council of Research-IBFM, Section of Genoa, Genova, Italy., Department of Mathematics, University of Genoa, Genova, Italy., Nuclear Medicine Unit, Department of Health Sciences, University of Genoa, Genova, Italy.