Hematolymphoid neoplasms are common in bone marrow biopsies performed for non-specific, diffuse marrow signal...

MRI is an imaging modality used for a wide range of clinical indications. Occasionally, non-specific, diffuse T1 marrow signal alterations are identified, which may prompt a bone marrow biopsy (BM). However, there is little data on the clinicopathologic significance of this signal alteration. This study evaluated the frequency and nature of pathologic findings in BM performed to evaluate diffuse MRI T1 marrow signal alterations.

Records from January 2003 to May 2015 were searched for BM performed to evaluate abnormal MRIs. 179 cases were identified. Patients with nodular/destructive bone lesions on MRI or other imaging studies, or a previous diagnosed metastatic tumor or hematologic malignancy were excluded, resulting in 45 cases.

The patients included 22 males and 23 females with a median age of 56 years. The location of the MRI T1 marrow signal alterations included spine, pelvis, knee, skull, femur, and arm. 19/45 patients had neoplasms identified in the BM. The remaining 26 patients had benign BM findings. There was a significant difference in hemoglobin values in patients with neoplastic versus benign BM findings (p = 0.037, unpaired Student's t-test).

Diffuse T1 marrow signal alterations on MRI should warrant a BM evaluation, as 42% of cases showed an underlying hematolymphoid neoplasm or metastatic tumor, even when patients with a known history of malignancy were excluded. When faced with a BM from a patient with a non-specific, diffuse MRI signal alteration, a pathologist should have a high index of suspicion for a malignant neoplasm, most often of hematopoietic/lymphoid type.