Contrast-enhanced ultrasonography vs MRI for evaluation of local invasion by cervical cancer

Abstract

Objective:: The purpose of this study is to compare contrast-enhanced ultrasound (CEUS) to MRI for evaluating local invasion of cervical cancer.

Methods:: A total of 108 patients with cervical cancer were included in this study. All the enrolled patients were Stage IIA2-IVB according to the International Federation of Obstetrics and Gynecology and treated with volumetric modulated arc therapy. Tumour size in different dimensions was compared between MRI and CEUS. The correlation coefficients (r) between MRI and CEUS for diagnosing local invasion, parametrial extension, and invasion to vagina, uterine corpus and adjacent organs were assessed.

Results:: Measurements by MRI and CEUS were strongly correlated in the three dimensions: left-right r = 0.84, craniocaudal r = 0.86 and anteroposterior r = 0.88. Vaginal and parametrial invasion were detected by both MRI and CEUS with moderate concordance, and invasion of uterine corpus, bladder and rectum with good concordance.

Conclusion:: CEUS is comparable to MRI for measuring tumour size, with good concordance for evaluating invasion of cervical cancer.

Advances in knowledge:: CEUS is a less expensive non-invasive modality for assessment of tumour size and invasion of cervical cancer.

Figure 1.

Images of a 45-year-old female patient with invasive cervical carcinoma. (A) A hyperintense mass in the cervix was found by sagittal T ₂ weighted MRI (short arrows) with maximum C-C × A-P × left-right (L-R) dimensions of 39 × 38 × 36 mm. (B) The cervical mass was heterogeneously enhanced on T ₁ weighted MR images. (C, D) The hypointense cervical mass with heterogeneous enhancement (short arrows) filling the endocervix as revealed by axial T ₁ weighted and contrast-enhanced T ₁ weighted MR images with fat saturation. (E) A smaller hypoechoic mass was found by B-mode ultrasonography, with C-C × A-P × L-R dimensions of 44 × 35 × 36 mm (short arrows). (F−H) A well-defined cervical mass (short arrows) with hyperenhancement relative to adjacent normal myometrium was revealed in arterial phase (F) and a hypoenhanced cervical mass in venous phase appeared on both sagittal CEUS (G) and axial CEUS (H). AP, anteroposterior; CC, craniocaudal; CEUS, contrast-enhanced ultrasonography; LR, left-right.

Figure 2.

Images of bulk invasive cervical carcinoma in a 62-year-old female. (A) An isointense bulk cervical mass extending to the uterus and upper 2/3 of the vagina (shortarrows) was found by sagittal T ₂ weighted MRI. (B) The cervical mass with invasion of uterine corpus was heterogeneously enhanced on sagittal T ₁ weighted MR images with fat saturation. The boundary of the mass was indistinct and the fatty interspace between the cervical tumour and bladder was absent (thin arrow). (C, D) The cervical mass was indistinct on axial T ₂ weighted MR images and axial T ₁ weighted MR images with fat saturation. The bladder wall with low signal was discontinuous (thin arrow). (E, F) A hypoechoic ill-defined bulk cervical mass extending to the uterine corpus was demonstrated by B-mode ultrasound. The fatty interspace between cervix and bladder was absent. (G, H) The cervical mass was hyperenhanced in arterial phase and hypoenhanced in venous phase on CEUS (short arrows). The fatty interspace between cervix and bladder appeared hyperenhanced coincident with the cervical tumour in the arterial phase (thin arrows). The tumour protruded beyond the cervix, with local discontinuous corpus (white heavy arrows). CEUS, contrast-enhanced ultrasonography.