Endometrial Stromal Sarcoma of the Uterus: Magnetic Resonance Imaging Findings Including Apparent Diffusion Coefficient Value and Its Correlation With Ki-67 Expression

Abstract

Patients with ESS showed some characteristics on conventional MRI and DWI, and there was an inverse correlation between the ADC value and Ki-67 expression.

A Noninvasive Assessment of Tumor Proliferation in Lung cancer Patients using Intravoxel Incoherent Motion Magnetic Resonance Imaging

“…International Publisher diffusion-weighted imaging (DWI) can reflect tumor cellularity. In recent years, ADC values were reported to be associated with Ki-67 expression in various tumors, such as breast cancer [8,9], endometrial stromal sarcoma of the uterus [10], endometrial carcinoma [11], and lung cancer [12]. However, ADC values are calculated using a mono-exponential model that is affected not only with the molecular movements of water but also by capillary microcirculation [13].…”

Differentiation of uterine low-grade endometrial stromal sarcoma from rare leiomyoma variants by magnetic resonance imaging

“…Compared to leiomyosarcoma, less is known about the added value of DWI and ADC values in differentiation of LGESS from leiomyoma. Li et al reported that 12 of 13 LGESS cases showed high SI relative to uterine endometrium and skeletal muscle, except one case with iso SI 18 . Similar to their results, all LGESS cases in our study showed iso/high SI to sciatic nerve on DWI.…”

“…They were aware that patients had been diagnosed histologically as having either LGESS or rare leiomyoma variants, but they were blinded to all other clinical information. The following qualitative features were evaluated: on T2WI, (1) main site of the tumor (intramural, submucosal, or subserosal), (2) nodular and/or irregular border 15 , (3) extrauterine involvement, (4) worm-like nodular extension 15 , (5) intra-tumoral low SI bands 16 , (6) low SI rim surrounding intra-myometrial tumor 17 , (7) speckled appearance (reported to be characteristic of leiomyoma) 9 , 20 , (8) cystic and/or necrotic change 18 , (9) higher SI than outer myometrium; on T1WI images, (10) tumoral hemorrhage (intra-tumoral high SI), with worm-like nodular extension on T2WI defined as detached nodules from the primary tumor 15 , with speckled appearance defined as diffusely scattered high SI within the tumor on T2WI 20 . When DWI and CE-T1WI were available, the following features were assessed: (11) SI relative to sciatic nerve roots (iso or high vs low) on DWI and (12) heterogeneous tumor enhancement on CE-T1WI.…”

“…A pre-defined MRI system was created before evaluations of qualitative and quantitative MRI features above to avoid testimation (estimation after testing) bias. This system was based on T2WI and DWI features reported previously as a characteristic of LGESS: tumor with iso/high SI on DWI 18 relative to sciatic nerve roots and with either worm-like nodular extension 15 , intra-tumoral T2 low SI bands 16 , or T2 low SI rim 17 . Among patients with DWI (22 of LGESS group and all of Rare leiomyoma variant group), the two readers (R1/R2) used a Likert scale for independent evaluation of whether the uterine tumor met the criteria, or not.…”

“…Characteristic MRI features of LGESS have been reported in small case series: worm-like nodular extension 15 , intra-tumoral low signal intensity (SI) bands on T2 weighted-images (T2WI) 16 , and low SI rim on T2WI 17 . Li et al reported that 13 of 14 patients (93%) showed high SI on DWI 18 . Nevertheless, no report of the relevant literature describes the diagnostic performance of MRI in differentiation from leiomyoma, especially from rare leiomyoma variants.…”