MRI to assess response after neoadjuvant chemotherapy in breast cancer subtypes: a systematic review and meta-analysis

Abstract

This meta-analysis aimed to estimate and compare sensitivity, specificity, positive- (PPV) and negative predictive value (NPV) of magnetic resonance imaging (MRI) for predicting pathological complete remission (pCR) after neoadjuvant chemotherapy (NAC) in patients with early-stage breast cancer. We stratified for molecular subtype by immunohistochemistry (IHC) and explored the impact of other factors. Two researchers systematically searched PUBMED and EMBASE to select relevant studies and extract data. For meta-analysis of sensitivity and specificity, we used bivariate random-effects models. Twenty-six included studies contained 4497 patients. There was a significant impact of IHC subtype on post-NAC MRI accuracy (p = 0.0082) for pCR. The pooled sensitivity was 0.67 [95% CI 0.58–0.74] for the HR−/HER2−, 0.65 [95% CI 0.56–0.73] for the HR−/HER2+, 0.55 [95% CI 0.45–0.64] for the HR+/HER2− and 0.60 [95% CI 0.50–0.70] for the HR+/HER2+ subtype. The pooled specificity was 0.85 [95% CI 0.81–0.88] for the HR−/HER2−, 0.81 [95% CI 0.74–0.86] for the HR−/HER2+, 0.88[95% CI 0.84–0.91] for the HR+/HER2− and 0.74 [95% CI 0.63–0.83] for the HR+/HER2+ subtype. The PPV was highest in the HR-/HER2- subtype and lowest in the HR+/HER2− subtype. MRI field strength of 3.0 T was associated with a higher sensitivity compared to 1.5 T (p = 0.00063). The accuracy of MRI for predicting pCR depends on molecular subtype, which should be taken into account in clinical practice. Higher MRI field strength positively impacts accuracy. When intervention trials based on MRI response evaluation are designed, the impact of IHC subtype and field strength on MR accuracy should be considered.

Soluble NKG2DLs Are Elevated in Breast Cancer Patients and Associate with Disease Outcome

“…In addition, it would be interesting to further analyze whether sNKG2DLs are useful for assessing the response to neoadjuvant therapy in breast cancer patients. To date, response assessment to neoadjuvant therapy in breast cancer is primarily performed using imaging modalities such as MRI, ultrasound, and mammography [55][56][57][58][59]; therefore, sNKG2DL levels in relation to neoadjuvant therapy may serve as a complementary, easyto-use, cost-effective, and non-invasive tool for response assessment that could benefit many patients.…”

Tumor infiltrating lymphocytes and change in tumor load on MRI to assess response and prognosis after neoadjuvant chemotherapy in breast cancer

“…We did not have enough data to evaluate the relationship with TILs in the residual tumor to RFS, but work is underway to incorporate TILs in the residual tumor after NAC in the RCB to further stratify post-neoadjuvant prognosis(38).Since MRI is more accurate in evaluating response to NAC compared to mammography, ultrasound and physical examination, it is widely used in clinical practice (39)(40)(41). Radiological assessment alone is, however, not accurate enough to guide treatment decisions (42). A (semi-) automated method for evaluating response to NAC could be of interest, since manual measurement by RECIST is associated with intra-and interobserver variability (43)(44)(45).…”

Machine learning approaches in the prediction of positive axillary lymph nodes post neoadjuvant chemotherapy using MRI, CT, or ultrasound: A systematic review

“…Currently, however, axillary LN response to NAC is rarely assessed by CT [11] . Furthermore, the results of the SENTINA and ACOSOG 1071 studies indicated that sentinel lymph node biopsy (SLNB) after NAC had a false negative rate of greater than 10 % for patients with unselected breast cancer [9] , [12] , [13] , [14] , [15] .…”