Ann Anstee MBBS, Presenter: Nothing to Disclose

Fiona Scott, Abstract Co-Author: Nothing to Disclose

Linda Culver, Abstract Co-Author: Nothing to Disclose

Gordon Rustin MD, Abstract Co-Author: Nothing to Disclose

Malcolm Padwick, Abstract Co-Author: Nothing to Disclose

Anwar Roshanali Padhani MD, Abstract Co-Author: Nothing to Disclose

Endometrial cancer aggressiveness is dependent on histological grade (determined by gland formation, cellularity and necrosis). The purpose of this MRI study was to record water diffusion coefficients of normal uterine structures and to correlate water diffusion with tumor grade and stage of endometrial cancer.

To date, 17 women with endometrial cancer (85% undergoing hysterectomy) were evaluated at 1.5 & 3 Tesla using multiplanar T2W, dynamic T1W contrast enhanced and single shot EPI diffusion-weighted MRI (b=0, 50, 150, 500, 1000 sec/mm2) for staging purposes. Apparent diffusion coefficients (ADC from all b-values; units mm2/sec) of imaging determined and histologically confirmed normal myometrium, cervix stroma and cervical mucosa were obtained. Tumor ADCs were correlated with histological grade and pathological stage.

An overlap in ADC values between cervical mucosa (median=132.6; inter quartile range=56.4) and myometrium (median=124.9; inter quartile range=43.5) was observed but both were greater than cervix stroma (median= 62; inter quartile range=59.1)(Mann-Whitney test; p=0.002). 15 tumors: 13 endometrioid carcinomas (grade 1=6; grade 2=3; grade 3=6), 1 clear cell (grade=3) and 1 mullerian tumor (grade=3) were found at pathology. The pathological tumor stage for the 17 tumors were T0 =1; T1a/b =2; T1C =8; T2 =3; T3=3. There was a significant difference between ADC values of tumors (median=72.7; inter quartile range=12.3) and myometrium (p=0.001) with greater water restriction in tumors. There was a negative Kendall’s rank correlation between adenocarcinoma ADC and histological grade (tau = -0.52, p=0.018) and pathological stage (tau = -0.60, p=0.006); that is aggressive lesions had lower ADC values.

Intrinsic differences in water diffusion profile between normal myometrium and tumor enable tumor detection on MRI and also reflect aggressiveness of histological lesion.

Water diffusion MRI represents a novel contrast mechanism for the evaluation of endometrial cancer that also appears to reflect tumor aggressiveness.

Anstee, A, Scott, F, Culver, L, Rustin, G, Padwick, M, Padhani, A, Diffusion-weighted MRI: Correlation of Water Diffusion with Tumor Grade and Stage in Endometrial Cancer and Normal Tissue.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4434282.html