Zervixkarzinom: Präoperatives Staging mittels Magnetresonanztomographie

Comparison between readout-segmented and single-shot echo-planar imaging in the evaluation of cervical cancer staging

OBJECTIVE:

To compare the performance of diffusion-weighted imaging (DWI) based on readout-segmented echo-planar imaging (RESOLVE) and single-shot EPI (SS-EPI) sequence in evaluating cervical cancer staging.

METHODS:

61 patients with cervical cancer underwent DWI based on SS-EPI and RESOLVE. Two blinded readers independently assessed two sets of DW images for distinction of anatomical structures, delineation of lesion, susceptibility artefact and overall image quality on a 4-point scale. Geometric distortion was evaluated by measuring lesion anteroposterior (AP) length and left-right (LR) width derived from T₂W images and those obtained from the corresponding DW images. Staging of cervical cancer on SS-EPI and RESOLVE were compared with T₂WI and gold-standard of pathological findings.

RESULTS:

RESOLVE was significantly superior to SS-EPI for all four criteria regarding qualitative comparisons (all p < 0.05). Regarding the geometric distortion, AP length on SS-EPI was significantly different from that of T₂WI (p < 0.05), whereas there were no significant differences between RESOLVE and T₂WI (both p > 0.05). The staging of SS-EPI was overestimated, while RESOLVE had a better consistency with pathological staging than SS-EPI in staging of cervical cancer. There was no significant difference in apparent diffusion coefficient value between SS-EPI and RESOLVE (p < 0.05).

CONCLUSION:

RESOLVE is superior to SS-EPI in the accuracy of cervical cancer staging because of the improvement in image quality.

ADVANCES IN KNOWLEDGE:

RESOLVE has a more accurate value comparable to SS-EPI in cervical cancer staging, with the advantage of the improvement in image quality and reduced geometric distortion.

Monitoring treatment response in patients undergoing chemoradiotherapy for locally advanced uterine cervical cancer by additional diffusion-weighted imaging: A systematic review

PURPOSE

To determine the role of diffusion-weighted imaging (DWI) in evaluating response to chemoradiotherapy in patients with uterine cervical cancer.

MATERIALS AND METHODS

A search was performed in MEDLINE and EMBASE from January 2005 to April 2014 using search terms related to uterine cervical cancer and magnetic resonance imaging. Two reviewers independently checked the studies for inclusion criteria, patient population, magnetic resonance imaging (MRI) parameters and analysis, follow-up for treatment response, apparent diffusion coefficient (ADC) values, and quality assessment.

RESULTS

Nine studies with 231 patients were included. International Federation of Gynecology and Obstetrics (FIGO) staging varied from Ib1 to IVb and mean age from 42 to 67 years. When baseline and after treatment pooled mean ADC values were compared, complete responders showed higher increase (0.88 × 10(-3) mm(2) /s to 1.50 × 10(-3) mm(2) /s; Δ0.62 × 10(-3) mm(2) /s) compared to partial responders (1.03 × 10(-3) mm(2) /s to 1.42 × 10(-3) mm(2) /s; Δ0.39 × 10(-3) mm(2) /s) and to nonresponders (0.87 × 10(-3) mm(2) /s to 1.18 × 10(-3) mm(2) /s; Δ0.31 × 10(-3) mm(2) /s). Individual studies also showed that an ADC of ≤0.31 was only seen in nonresponders and an increase of ADC of ≥0.62 was only seen in complete responders. The number of datasets for monitoring early response (at 2 or 4 weeks of therapy) were low and comparable increases in pooled mean ADC values between complete responders, partial responders, and nonresponders were seen. Data on quality assessment showed high risk of bias concerning patient selection, DWI evaluation, and flow and timing.

CONCLUSION

DWI can be used for monitoring treatment response after treatment, but not for the early response monitoring.

Uterine cervical malignancy: diagnostic accuracy of MRI with histopathologic correlation

Objective:

Cervical cancer is the third most common malignancy in women worldwide. Accurate staging of the disease is crucial in planning the optimal treatment strategy. The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in the assessment of extension and staging of cervical malignancy in correlation with histopathologic examination.

Materials and Methods:

Thirty females with untreated pathologically proven uterine cervical carcinoma were included in this prospective study. The patients were 40 - 65 years of age and their average age was 45 years. All patients were subjected to routine clinical staging workup and underwent MRI for preoperative staging. Preoperative MRI findings were reviewed and compared with the final pathological staging that is the Gold Standard of reference.

Results:

Histopathologic examination established that of the 30 tumors, 22 (73.3%) were squamous cell carcinoma. According to the International Federation of Gynecology and Obstetrics (FIGO) staging criteria, 2/30 patients (6.6%) were stage IB, 12/30 (40.3%) were IIA, 8/30 were IIB (26.6%), and 8/30 (26.6%) were IVA. MRI had a sensitivity of 100% and specificity 85.7% in the detection of parametrial infiltration, and a sensitivity of 100% and specificity of 90% in the detection of vaginal infiltration. It was sensitive (100%) and specific (100%) in detecting tumor extension to the stroma, urinary bladder, and rectum. Pathological examination demonstrated stage IB cervical carcinoma in 2/30 patients (6.6%), stage IIA disease in 10/30 patients (33.3%), stage IIB in 6/30 patients (20%), and stage IV disease in 8/30 patients (26.6%). MRI features demonstrated stage IB in 2/30 patients (6.6%), stage IIA disease in 12/30 patients (40%), stage IIB in 8/30 patients (26.6%), and stage IV disease in 8/30 patients (26.6%). MRI staging of cervical carcinoma was in concordance with histopathologic staging in stages IB and IVA and over-staging in IIA and IIB stages.

Conclusion:

MRI is an optimal non-invasive modality for preoperative staging of uterine cervical malignancy, and crucial in subsequent more accurate treatment planning.