BACKGROUNDConventional magnetic resonance (MR) scanning techniques can identify bone marrow (BM) containing mostly fat cells. But they are not able to differentiate BM tumor infiltration, BM fibrosis and normal red BM. This is particularly problematic in assessment of recurrent or refractory hematological malignancy. This pilot study used dynamic contrast-enhanced MR imaging (DCE-MRI) to evaluate the bone marrow status and to determine whether several calculated parameters derived from the DCE-MRI correlate with histological characteristics of marrow, especially with the tumor fraction (TF).

METHODSDCE-MRI scans were performed in 25 patients with proven or known hematological malignancy who were about to undergo bone marrow biopsy of the posterior iliac crest. The location chosen for biopsy was examined with MRI approximately one hour prior to the biopsy. Time-signal intensity curves (TIC) were generated from the region of the iliac crest corresponding to the planned biopsy site. Enhancement parameters were calculated, including peak enhancement ratio (PER), maximum enhancement slope (Slope(max)), time to peak (TTP) and mean time (MT). The biopsy specimen was reported synoptically, with relevant reported parameters including cellularity and tumor fraction (TF).

RESULTSPER values were significantly higher for the bone marrow tumor infiltration group than for the normal bone marrow group (P < 0.05). A significant positive correlation was found between PER and TF as well as Slope(max) and TF. A negative correlation was found between TTP and TF. There was no significant difference in the mean TTP and MT values between the BM tumor infiltration group and the normal bone marrow group.

CONCLUSIONSThe presence of diffuse bone marrow infiltration in patients with haematological malignancies could be verified using DCE-MRI.