Objective To explore the
incidence and significance of intra-and extraosseous
edema accompanying benign
tumors and
tumor like
diseases.
Methods Imaging studies including MR,CT and plain radiograph were retrospectively reviewed in 245 cases of benign osseous
tumors and
tumor like
diseases proved by
pathology(borderline
tumor,cases associated with
pathological fractures,cases with lesions of
skull were excluded from the study).The
incidence of
bone marrow and soft
tissue edema were defined on T2WI with fat
suppression on MRI in all the cases.x2 test was performed for the
incidence rate of
edema in the benign
tumors and
tumor like
diseases.The pre-operative
diagnoses were reviewed,and the influence of
edema to the
differential diagnosis between the benign and malignant was analyzed.Results The total
incidence of
bone marrow and soft
tissue edema associated with benign
tumors and
tumor like
diseases was 37.1% (91/245),which included
Langerhans cell histiocytosis 85.2% (23/27),osteoblastoma85.0% (17/20),osteoid osteoma93.6% (29/31),ehondroblastoma 87.0% (20/23).There was no statistically significant difference of
edema incidence among the above-mentioned four
diseases.(x2=6.35,P> 0.05).Both cases of endosteal
capillary hemangioma had
edema around.No
edema was found around the lesions of other kinds of
diseases.41 of 91 cases (45.1%) with
edema were misdiagnosed as malignant
tumor by MRI pre-operatively.Conclusion The
marrow and soft
tissue edema is a common sign in the benign
bone tumor and
tumor-like
diseases,and it is frequently seen in
Langerhans cell histiocytosis,
osteoblastoma,
osteoid osteoma,
chondroblastoma.