PURPOSE: Osteonecrosis (ON) is a devastating complication of high dose corticosteroid therapy in cancer patients. Core decompression for prevention of bone collapse has been recently combined with the delivery of autologous concentrated bone marrow aspirates. The purpose of our study was to develop an imaging test for the detection of transplanted bone marrow cells in ON lesions.EXPERIMENTAL DESIGN: In a prospective proof-of-concept clinical trial (NCT02893293), we performed serial MR imaging studies of nine hip joints of seven ON patients before and after core decompression. 24-48hours prior to the surgery, we injected ferumoxytol nanoparticles intravenously to label cells in normal bone marrow with iron oxides. During the surgery, iron labeled bone marrow cells were aspirated from the iliac crest, concentrated and then injected into the decompression track. Following surgery, patients received follow-up MRI up to 6 months after bone marrow cell transplantation.RESULTS: Iron labeled cells could be detected in the access canal by a dark (negative) signal on T2*-weighted MR images. T2* relaxation times of iron labeled cell transplants were significantly lower compared to unlabeled cell transplants of control patients who were not injected with ferumoxytol (P = 0.02). Clinical outcomes of patients who received ferumoxytol-labeled or unlabeled cell transplants were not significantly different (P = 1), suggesting that the added ferumoxytol administration did not negatively affect bone repair.CONCLUSIONS: This immediately clinically applicable imaging test could become a powerful new tool to monitor the effect of therapeutic cells on bone repair outcomes after corticosteroid-induced osteonecrosis.
View details for PubMedID 30224340