Meta-analysis of agreement between MRI and pathologic breast tumour size after neoadjuvant chemotherapy

Abstract

Background:Magnetic resonance imaging (MRI) has been proposed to guide breast cancer surgery by measuring residual tumour after neoadjuvant chemotherapy. This study-level meta-analysis examines MRI's agreement with pathology, compares MRI with alternative tests and investigates consistency between different measures of agreement.Methods:A systematic literature search was undertaken. Mean differences (MDs) in tumour size between MRI or comparator tests and pathology were pooled by assuming a fixed effect. Limits of agreement (LOA) were estimated from a pooled variance by assuming equal variance of the differences across studies.Results:Data were extracted from 19 studies (958 patients). The pooled MD between MRI and pathology from six studies was 0.1 cm (95% LOA: −4.2 to 4.4 cm). Similar overestimation for MRI (MD: 0.1 cm) and ultrasound (US) (MD: 0.1 cm) was observed, with comparable LOA (two studies). Overestimation was lower for MRI (MD: 0.1 cm) than mammography (MD: 0.4 cm; two studies). Overestimation by MRI (MD: 0.1 cm) was smaller than underestimation by clinical examination (MD: −0.3 cm). The LOA for mammography and clinical examination were wider than that for MRI. Percentage agreement between MRI and pathology was greater than that of comparator tests (six studies). The range of Pearson's/Spearman's correlations was wide (0.21–0.92; 16 studies). Inconsistencies between MDs, percentage agreement and correlations were common.Conclusion:Magnetic resonance imaging appears to slightly overestimate pathologic size, but measurement errors may be large enough to be clinically significant. Comparable performance by US was observed, but agreement with pathology was poorer for mammography and clinical examination. Percentage agreement can provide supplementary information to MDs and LOA, but Pearson's/Spearman's correlation does not provide evidence of agreement and should be avoided. Further comparisons of MRI and other tests using the recommended methods are warranted.

Optical Mammography Using Diffuse Optical Spectroscopy for Monitoring Tumor Response to Neoadjuvant Chemotherapy in Women with Locally Advanced Breast Cancer

“…To date, DCE-MRI is the most accurate response assessment (24). However, this modality is not in all breast tumors equally reliable.…”

Breast Magnetic Resonance Imaging: Are Those Who Need It Getting It?

“…The conclusions from our exchanges were summarized in a written document that was circulated to all 28 15,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] Recommend or consider MRI in these situations: members of the breast team for final approval (the 21 who had attended the meeting and the few who had not been able to attend). The final document was then sent by e-mail to all physicians involved in breast care at our institution, and a printout of the consensus was made easily accessible to clinicians and radiologists at their clinics and workstations.…”

Novel Strategies for Breast Cancer Imaging: New Imaging Agents to Guide Treatment

“…Traditional imaging methods, such as MRI, CT, and bone scanning, have a limited ability to predict or monitor treatments that specifically target proliferation and produce a cytostatic response (8). 18 F-FDG measures of cancer metabolism allow early insight into the response of breast cancer metastatic disease to cytotoxic and endocrine agents but do not measure proliferation (9) and do not correlate with tumor proliferative status or growth rate (10).…”