Clinical and imaging correlation in patients with pathologically confirmed tumefactive demyelinating lesions

Abstract

Objectives: To characterize clinical and imaging features in patients with pathologically confirmed demyelinating lesions.

Methods: In this retrospective chart review, we analyzed clinical-radiological-pathological correlations in patients >15years old who underwent brain biopsy at our institution between 2000 and 2015 and had inflammatory demyelination on neuropathology.

Results: Of 31 patients, the mean age was 42years (range 16 to 69years) and 55% were female. All but one of the biopsied lesions were considered tumefactive demyelinating lesions (TDLs) by imaging criteria, measuring >2cm on contrast-enhanced brain MRI. On clinical follow-up, the final diagnosis was a CNS malignancy in 2 patients (6.5%). In patients without malignant tumor, the TDL was solitary in 12 (41%) and multifocal in 17 (59%), with contrast enhancement in all but one case, primarily in an incomplete rim enhancement pattern (75.9%). Of 16 patients with at least 12months of clinical follow-up, 7 (43.8%) had a clinical relapse. Of patients without a prior neurologic history, relapse occurred in 2/7 (29%) in solitary TDL and 2/6 (33%) in multifocal lesions at initial presentation. Recurrent TDLs occurred in 3 patients, all with initially solitary TDLs. Stratifying by CSF analysis, 4 of 6 patients (67%) with either an elevated IgG Index or >2 oligoclonal bands suffered a clinical relapse compared to 2/8 (25%) with non-inflammatory CSF.

Conclusions: Pathologically confirmed TDLs call for careful clinical correlation, clinical follow-up and imaging surveillance. Although sometimes clinically monophasic, tumefactive demyelinating lesions carried nearly a 45% risk of near-term clinical relapse in our study, even when presenting initially as a solitary mass lesion.

Keywords: Brain biopsy; Demyelination; MRI; Multiple sclerosis; Neuropathology; Tumefactive.

Figure 1

Imaging Patterns of Brain-biopsy Confirmed Tumefactive Demyelinating Lesions: A) Solitary TDL with cystic appearance (T1 post-gadolinium); B) multifocal demyelinating lesions (T1 post-gadolinium); C) Balo-like tumefactive demyelinating lesion showing concentric rings of demyelination (FLAIR). Enhancement patterns can include: D) Incomplete rim enhancement; E) nodular enhancement; F) and patchy enhancement (D–F, T1 post-gadolinium). Each scan is from a different individual, none of whom were later diagnosed with a malignancy on follow-up.