Utility of preoperative ferumoxtran-10 enhanced MRI to evaluate retroperitoneal lymph node metastasis in advanced cervical cancer: Results of ACRIN 6671/GOG 0233.

Abstract

5035 Background: Ferumoxtran-10 MRI has been evaluated for lymph node (LN) metastasis. Objective of the study was to determine utility of ferumoxtran-10 MRI in detection of LN metastasis in advanced cervical cancer. Methods: This is an NCI funded phase II multicenter clinical trial conducted by ACRIN/GOG. Patients with locally advanced cervical cancer undergoing pelvic and abdominal lymphadenectomy prior to chemoradiation were accrued. Preoperative MRI including T2W, T1W, and T2*GRE were obtained following IV administration of ferumoxtran -10 that was provided by AMAG Pharmaceutical Inc. Results of a blinded review by 7 imagers were correlated with pathology findings. Readers reviewed ferumoxtran-10 insensitive sequences (standard MRI) followed by all sequences including ferumoxtran-10 sensitive (T2*GRE) sequence. Correlation was made per region for 8 regions, left and right (para-aortic, common iliac, external iliac, and obturator) LNs. Ferumoxtran-10 MRI was considered positive when there was a defect in LN on T2*GRE. Standard MRI was considered positive when LN short axis was > 8mm. Results: Thirty three women (mean age 49 ± 11) were included. Mean cervical tumor size was 5.4±1.5cm. Prevalence of LN metastasis was 36% (12/33) in abdomen and 67% (22/33) in pelvis. Median size of largest focus of cancer was 18mm (range 2-50, Q1 11mm). Average sensitivity/specificity for seven readers on ferumoxtran-10 MRI were 0.60 (95% CI:0.49-0.70)/0.75 (95% CI: 0.67-0.82) in abdomen, and 0.81 (95% CI:0.73-0.86)/0.45 (95% CI: 0.32-0.58) in pelvis. Corresponding numbers for standard MRI were 0.54 (95% CI:0.43-0.64)/0.83 (95% CI: 0.75-0.88) and 0.74 (95% CI:0.67-0.80)/0.71 (95% CI: 0.58-0.82). Use of ferumoxtran-10 showed no significant difference in the diagnostic accuracy of MRI with the exception of specificities in pelvis (p=0.006). Performances of the seven readers were comparable (p>0.32). Conclusions: In this cohort, ferumoxtran -10 MRI showed modest accuracy that was not significantly different from standard MRI. ACRIN/GOG receive funding from the National Cancer Institute through grants U01 CA079778 and U01 CA080098/ CA 27469 and CA 37517.