Predictive value of neoadjuvant chemotherapy failure in breast cancer using FDG–PET after the first course

ACR Appropriateness Criteria® Imaging of the Axilla

This publication reviews the current evidence supporting the imaging approach of the axilla in various scenarios with broad differential diagnosis ranging from inflammatory to malignant etiologies. Controversies on the management of axillary adenopathy results in disagreement on the appropriate axillary imaging tests. Ultrasound is often the appropriate initial imaging test in several clinical scenarios. Clinical information (such as age, physical examinations, risk factors) and concurrent complete breast evaluation with mammogram, tomosynthesis, or MRI impact the type of initial imaging test for the axilla. Several impactful clinical trials demonstrated that selected patient's population can received sentinel lymph node biopsy instead of axillary lymph node dissection with similar overall survival, and axillary lymph node dissection is a safe alternative as the nodal staging procedure for clinically node negative patients or even for some node positive patients with limited nodal tumor burden. This approach is not universally accepted, which adversely affect the type of imaging tests considered appropriate for axilla. This document is focused on the initial imaging of the axilla in various scenarios, with the understanding that concurrent or subsequent additional tests may also be performed for the breast. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Breast tumour volume and blood flow measured by MRI after one cycle of epirubicin and cyclophosphamide-based neoadjuvant chemotherapy as predictors of pathological response

OBJECTIVES

Better markers of early response to neoadjuvant chemotherapy (NACT) in patients with breast cancer are required to enable the timely identification of non-responders and reduce unnecessary treatment side-effects. Early functional imaging may better predict response to treatment than conventional measures of tumour size. The purpose of this study was to test the hypothesis that the change in tumour blood flow after one cycle of NACT would predict pathological response.

METHODS

In this prospective cohort study, dynamic contrast-enhanced MRI was performed in 35 females with breast cancer before and after one cycle of epirubicin and cyclophosphamide-based NACT (EC90). Estimates of tumour blood flow and tumour volume were compared with pathological response obtained at surgery following completion of NACT.

RESULTS

Tumour blood flow at baseline (mean ± SD; 0.32 ± 0.17 ml/min/ml) reduced slightly after one cycle of NACT (0.28 ± 0.18 ml/min/ml). Following treatment 15 patients were identified as pathological responders and 20 as non-responders. There were no relationships found between tumour blood flow and pathological response. Conversely, tumour volume was found to be a good predictor of pathological response (smaller tumours did better) at both baseline (area under the receiver operating characteristic curve 0.80) and after one cycle of NACT (area under the receiver operating characteristic curve 0.81).

CONCLUSION & ADVANCES IN KNOWLEDGE

The change in breast tumour blood flow following one cycle of EC90 did not predict pathological response. Tumour volume may be a better early marker of response with such agents.

The early prediction of pathological response to neoadjuvant chemotherapy and prognosis: comparison of PET Response Criteria in Solid Tumors and European Organization for Research and Treatment of Cancer criteria in breast cancer

OBJECTIVE

To compare the predictive value of European Organization for Research and Treatment of Cancer (EORTC) criteria and PET Response Criteria in Solid Tumors (PERCIST), for the pathological response and prognosis of patients with breast cancer receiving neoadjuvant chemotherapy (NAC).

METHODS

Consecutive PET/computed tomography scans in 128 operable female patients at baseline and after two courses of NAC were performed. Patients were categorized by complete metabolic response (CMR) and non-CMR groups using 2 PET criteria. CMR and non-CMR were used to predict pathological complete response (pCR) by diagnostic test evaluation, and to predict progression-free survival (PFS) using Kaplan-Meier plots and Cox proportional hazards regression.

RESULTS

Ninety-two patients were finally analyzed. The sensitivity, specificity, and accuracy for pCR prediction were 69.7, 76.3, and 73.9% with EORTC criteria, and 69.7, 77.9, and 75.0% with PERCIST, respectively. Peak standardized uptake value normalized to lean body mass (SULpeak), maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) were pCR response with accuracy of 70.7, 60.0, 75.0, and 71.4%, respectively. CMR by the EORTC (P = 0.021) and PERCIST (P = 0.007) was significantly related to a longer PFS. The univariate and multivariate analysis suggested that CMR by PERCIST was an independent predictor of recurrence (P = 0.008).

CONCLUSION

EORTC criteria and PERCIST had early predictive value to long-term outcome, but moderate value for pCR. Furthermore, PERCIST might show more potential than the EORTC criteria and conventional PET-based parameters to predict prognosis in breast cancer patients following two cycles of neoadjuvant chemotherapy.Video abstract: see http://links.lww.com/NMC/A162.

Utility of 18F-FDG PET/CT for predicting pathologic complete response in hormone receptor-positive, HER2-negative breast cancer patients receiving neoadjuvant chemotherapy

BACKGROUND

Pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) is a predictor of improved outcomes in breast cancer. In patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2) -negative breast cancer, the response to NAC is variable and mostly limited. This study was an investigation of the predictive relevance of parameters of 18F-FDG PET/CT for the pCR to NAC in patients with HR-positive, HER2-negative breast cancer.

METHODS

AH total of 109 consecutive HR-positive and HER2-negative breast cancer patients who were treated with NAC were enrolled in this prospective cohort study. The relationships between pretreatment 18F-FDG PET/CT and clinical outcomes including pathologic response to NAC were evaluated.

RESULTS

All patients finished their planned NAC cycles and eight patients (7.3%) achieved pCR. In the receiver operating characteristic (ROC) curve analysis, pSUVmax exhibited high sensitivity and specificity for predicting pCR. Furthermore, multivariate logistic regression analysis revealed pSUVmax as a predictive factor for pCR (hazard ratio = 17.452; 95% CI = 1.847-164.892; p = 0.013).

CONCLUSION

The results of this study suggest that 18F-FDG PET/CT pSUVmax is a predictive factor for pCR of HR-positive, HER2-negative breast cancer to NAC.

Prognostic value of 18F-FDG PET and PET/CT for assessment of treatment response to neoadjuvant chemotherapy in breast cancer: a systematic review and meta-analysis

Background

We performed a systematic review and meta-analysis to evaluate the prognostic significance of ¹⁸F-FDG PET and PET/CT for evaluation of responses to neoadjuvant chemotherapy (NAC) in breast cancer patients.

Methods

We searched PubMed, Embase, and the Cochrane Library databases until June 2020 to identify studies that assessed the prognostic value of ¹⁸F-FDG PET scans during or after NAC with regard to overall (OS) and disease-free survival (DFS). Hazard ratios (HRs) and their 95% confidence intervals (CIs) were pooled meta-analytically using a random-effects model.

Results

Twenty-one studies consisting of 1630 patients were included in the qualitative synthesis. Twelve studies investigated the use of PET scans for interim response evaluation (during NAC) and 10 studies assessed post-treatment PET evaluation (after NAC). The most widely evaluated parameter distinguishing metabolic responders from poor responders on interim or post-treatment PET scans was %ΔSUVmax, defined as the percent reduction of SUVmax compared to baseline PET, followed by SUVmax and complete metabolic response (CMR). For the 17 studies included in the meta-analysis, the pooled HR of metabolic responses on DFS was 0.21 (95% confidence interval [CI], 0.14–0.32) for interim PET scans and 0.31 (95% CI, 0.21–0.46) for post-treatment PET scans. Regarding the influence of metabolic responses on OS, the pooled HRs for interim and post-treatment PET scans were 0.20 (95% CI, 0.09–0.44) and 0.26 (95% CI, 0.14–0.51), respectively.

Conclusions

The currently available literature suggests that the use of ¹⁸F-FDG PET or PET/CT for evaluation of response to NAC provides significant predictive value for disease recurrence and survival in breast cancer patients and might allow risk stratification and guide rational management.

[18F]FDG PET/CT in the staging of inflammatory breast cancer: A systematic review

Up to 78 % of patients with inflammatory breast cancer (IBC) present with axillary lymph node involvement and up to 40 % with distant metastases. Previous studies indicate that 2-deoxy-2-(¹⁸F)fluoro-d-glucose ([¹⁸F]FDG) positron emission tomography/computed tomography (PET/CT) might be used for initial staging in patients with inflammatory breast cancer (IBC). In other cancer types, [¹⁸F]FDG PET/CT has been demonstrated to be a sensitive technique, providing complementary information on locoregional and distant disease to conventional imaging modalities. This systematic review showed that ¹⁸F]FDG PET/CT detects additional locoregional lymph node metastases and distant metastases in 10.3 % of patients, that were not detected with standard staging imaging. Compared with conventional imaging procedures, [¹⁸F]FDG PET/CT had better diagnostic performance for detection of locoregional and distant metastases and should standardly be used in the diagnostic work-up of IBC patients.

A Qualitative Transcriptional Signature for Predicting Extreme Resistance of ER-Negative Breast Cancer to Paclitaxel, Doxorubicin, and Cyclophosphamide Neoadjuvant Chemotherapy

For estrogen receptor (ER)-negative breast cancer patients, paclitaxel (P), doxorubicin (A) and cyclophosphamide (C) neoadjuvant chemotherapy (NAC) is the standard therapeutic regimen. Pathologic complete response (pCR) and residual disease (RD) are common surrogate measures of chemosensitivity. After NAC, most patients still have RD; of these, some partially respond to NAC, whereas others show extreme resistance and cannot benefit from NAC but only suffer complications resulting from drug toxicity. Here we developed a qualitative transcriptional signature, based on the within-sample relative expression ordering (REO) of gene pairs, to identify extremely resistant samples to PAC NAC. Using gene expression data for ER-negative breast cancer patients including 113 pCR samples and 137 RD samples from four datasets, we selected 61 gene pairs with reversal REO patterns between the two groups as the resistance signature, denoted as NR61. Samples with more than 37 signature gene pairs that had the same REO patterns within the extremely resistant group were defined as having extreme resistance; otherwise, they were considered responders. In the GSE25055 and GSE25065 dataset, the NR61 signature could correctly identify 44 (97.8%) of the 45 pCR samples and 22 (95.7%) of the 23 pCR samples as responder samples, respectively; it also identified 13 (16.9%) of 77 RD samples and 8 (21.1%) of 38 RD samples as extremely resistant samples, respectively. Survival analysis showed that the distant relapse-free survival (DRFS) time of the 14 extremely resistant cases was significantly shorter than that of the 108 responders (P < 0.01; HR = 3.84; 95% CI = 1.91–7.70) in GSE25055. Similar results were obtained in GSE25065. Moreover, in the integrated data of the two datasets with 94 responders and 21 extremely resistant samples identified from RD patients, the former had significantly longer DRFS than the latter (P < 0.01; HR = 2.22; 95% CI = 1.26–3.90). In summary, our signature could effectively identify patients who completely respond to PAC NAC, as well as cases of extreme resistance, which can assist decision-making on the clinical therapy for these patients.

The use of 3'-deoxy-3'-18F-fluorothymidine (FLT) PET in the assessment of long-term survival in breast cancer patients treated with neoadjuvant chemotherapy

OBJECTIVE

To assess the role of serial FLT-PET scans during early neoadjuvant treatment as a prognostic marker of response to treatment and survival.

METHODS

This study is a prospective cohort study which draws from a larger original study which examined the utility of FLT-PET imaging across multiple cancers. Our cohort consisted of patients who had biopsy-confirmed breast cancer amenable to surgical resection. These patients underwent serial FLT-PET scans: the first scan prior to starting neoadjuvant chemotherapy (NAC), and a second scan shortly after starting NAC. SUV_mean was derived using an isocontour ROI drawn approximately half way between the SUV_max and background on three planes for each scan. The change in mean standardized uptake value (SUV_mean) for the primary tumor between these two scans was then calculated, and patients were stratified into "responder" and "non-responder" groups based on a cut-off of 20% arithmetic decrease in SUV_mean between the two scans. The rates of pathologic complete response (pCR) on subsequent surgical excision, overall survival (OS), and progression-free survival (PFS) were then compared between the two groups to assess for significant difference between responders and non-responders.

RESULTS

16 patients (n = 16) met criteria for inclusion and successfully underwent FLT-PET scans in the prescribed sequence of events. Seven of these patients had a decrease of 20% or larger between the two serial PET scans, making them "responders". The remaining nine patients were "non-responders" to NAC based on PET imaging. Between responders and non-responders, there was no significant difference in median PFS (7.9 years versus 3.7 years; p = 0.425) and median OS (7.5 years versus 5.0 years; p = 0.944). In the 14 patients who underwent surgical resection (n = 14), there was no significant difference in the rate of achieving pCR (33% vs. 14%; p = 0.5846) between responders and non-responders.

CONCLUSION

Further study of a larger sample size is needed to examine the potential role for FLT-PET in predicting response to neoadjuvant treatment, particularly in correlating with long-term overall and progression-free survival. Our study is limited by small sample size, but does suggest that FLT-PET has a role in the long-term prognosis of breast cancer treated with NAC and surgical resection which is worthy of further study.

Predictive and prognostic potential of volume-based metabolic variables obtained by a baseline 18F-FDG PET/CT in breast cancer with neoadjuvant chemotherapy indication

AIM

To investigate the usefulness of metabolic variables using ¹⁸F-FDG PET/CT in the prediction of neoadjuvant chemotherapy (NC) response and the prognosis in locally advanced breast cancer (LABC).

MATERIAL AND METHODS

Prospective study including 67 patients with LABC, NC indication and a baseline ¹⁸F-FDG PET/CT. After breast tumor segmentation, SUV variables (SUVmax, SUVmean and SUVpeak) and volume-based variables, such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG), were obtained. Tumors were grouped into molecular phenotypes, and classified as responders or non-responders after completion of NC. Disease-free status (DFs), disease-free survival (DFS), and overall survival (OS) were assessed. A univariate and multivariate analysis was performed to study the potential of all variables to predict DFs, DFS, and OS.

RESULTS

Fourteen patients were classified as responders. Median±SD of DFS and OS was 43±15 and 46±13 months, respectively. SUV and TLG showed a significant correlation (p<0.005) with the histological response, with higher values in responders compared to non-responders. MTV and TLG showed a significant association with DFs (p=0.015 and p=0.038 respectively). Median, mean and SD of MTV and TLG for patients with DFs were: 8.90, 13.73, 15.10 and 33.78, and 90.54 and 144.64, respectively. Median, mean and SD of MTV and TLG for patients with non-DFs were: 16.72, 29.70 and 31.09 and 90.89, 210.98 and 382.80, respectively. No significant relationships were observed with SUV variables and DFs. Volume-based variables were significantly associated with OS and DFS, although in multivariate analysis only MTV was related to OS. No SUV variables showed an association with the prognosis.

CONCLUSION

Volume-based metabolic variables obtained with ¹⁸F-FDG PET/CT, unlike SUV based variables, were good predictors of both neoadjuvant chemotherapy response and prognosis.

The application of positron emission tomography (PET/CT) in diagnosis of breast cancer. Part II. Diagnosis after treatment initiation, future perspectives

Similarly to the applications described in the first part of this publication, positron emission tomography with computed tomography (PET/CT) is also gaining importance in monitoring a tumour's response to therapy and diagnosing breast cancer recurrences. This is additionally caused by the fact that many new techniques (dual-time point imaging, positron emission tomography with magnetic resonance PET/MR, PET/CT mammography) and radiotracers (16α-18F-fluoro-17β-estradiol, 18F-fluorothymidine) are under investigation. The highest sensitivity and specificity when monitoring response to treatment is achieved when the PET/CT scan is made after one or two chemotherapy courses. Response to anti-hormonal treatment can also be monitored, also when new radiotracers, such as FES, are used. When monitoring breast cancer recurrences during follow-up, PET/CT has higher sensitivity than conventional imaging modalities, making it possible to monitor the whole body simultaneously. New techniques and radiotracers enhance the sensitivity and specificity of PET and this is why, despite relatively high costs, it might become more widespread in monitoring response to treatment and breast cancer recurrences.

FDG-PET/CT and MRI for Evaluation of Pathologic Response to Neoadjuvant Chemotherapy in Patients With Breast Cancer: A Meta-Analysis of Diagnostic Accuracy Studies

INTRODUCTION

This study compared the diagnostic test accuracy of magnetic resonance imaging (MRI) with that of (18)F-fluoro-2-glucose-positron emission tomography/computed tomography (FDG-PET/CT) imaging in assessment of response to neoadjuvant chemotherapy (NAC) in breast cancer.

METHODS

A systematic search was performed in PubMed and EMBASE (last updated in June 2015). Studies investigating the performance of MRI and FDG-PET or FDG-PET/CT imaging during or after completion of NAC in patients with histologically proven breast cancer were eligible for inclusion. We considered only studies reporting a direct comparison between these imaging modalities to establish precise summary estimates in the same setting of patients. Pathologic response was considered as the reference standard. Two authors independently screened and selected studies that met the inclusion criteria and extracted the data.

RESULTS

A total of 10 studies were included. The pooled estimates of sensitivity and specificity across all included studies were 0.71 and 0.77 for FDG-PET/CT (n = 535) and 0.88 and 0.55 for MRI (n = 492), respectively. Studies were subgrouped according to the time of therapy assessment. In the intra-NAC setting, FDG-PET/CT imaging outperformed MRI with fairly similar pooled sensitivity (0.91 vs. 0.89) and higher specificity (0.69 vs. 0.42). However, MRI appeared to have higher diagnostic accuracy than FDG-PET/CT imaging when performed after the completion of NAC, with significantly higher sensitivity (0.88 vs. 0.57).

CONCLUSION

Analysis of the available studies of patients with breast cancer indicates that the timing of imaging for NAC-response assessment exerts a major influence on the estimates of diagnostic accuracy. FDG-PET/CT imaging outperformed MRI in intra-NAC assessment, whereas the overall performance of MRI was higher after completion of NAC, before surgery.

IMPLICATIONS FOR PRACTICE

The timing of therapy assessment imaging exerts a major influence on overall estimates of diagnostic accuracy. (18)F-fluoro-2-glucose-positron emission tomography (FDG-PET)/computed tomography (CT) imaging outperformed magnetic resonance imaging (MRI) in intra-neoadjuvant chemotherapy assessment with fairly similar pooled sensitivity and higher specificity. However, MRI appeared to be more accurate than FDG-PET/CT in predicting pathologic response when used in the post-therapy setting.

PET Imaging of Breast Cancer: Role in Patient Management

Breast cancer is the most common malignancy in females. Imaging plays a critical role in diagnosis, staging and surveillance, and management of disease. Fluorodeoxyglucose (FDG) PET the imaging is indicated in specific clinical setting. Sensitivity of detection depends on tumor histology and size. Whole body FDG PET can change staging and management. In recurrent disease, distant metastasis can be detected. FDG PET imaging has prognostic and predictive value. PET/MR is evolving rapidly and may play a role management, assessment of metastatic lesions, and treatment monitoring. This review discusses current PET modalities, focusing on of FDG PET imaging and novel tracers.

Basal (18)F-FDG PET/CT as a predictive biomarker of tumor response for neoadjuvant therapy in breast cancer

PURPOSE

To explore the relation between tumor kinetic assessed by (18)F-FDG PET and final neoadjuvant chemotherapy (NC) response within a molecular phenotype perspective.

MATERIAL AND METHODS

Prospective study included 144 women with breast cancer. All patients underwent a dual-time point (18)F-FDG PET/CT previous to NC. The retention index (RI), between SUV-1 and SUV-2 was calculated. Molecular subtypes were re-grouped in low, intermediate and high-risk biological phenotypes. After NC, all residual primary tumor specimens were histopathologically classified in tumor regression grades (TRG) and response groups. The relation between SUV-1, SUV-2 and RI with the TRG and response groups was evaluated in all molecular subtypes and in accordance with the risk categories.

RESULTS

Responder's lesions showed significant greater SUVmax compared to non-responders. The RI value did not show any significant relation with response. Attending to molecular phenotypes, statistical differences were observed with greater SUV for responders having high-risk molecular subtypes.

CONCLUSION

Glycolytic tumor characteristics showed a significant correlation with NC response and dependence of risk phenotype.

A Phase II Study of 3'-Deoxy-3'-18F-Fluorothymidine PET in the Assessment of Early Response of Breast Cancer to Neoadjuvant Chemotherapy: Results from ACRIN 6688

Our objective was to determine whether early change in standardized uptake values (SUVs) of 3'deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) using PET with CT could predict pathologic complete response (pCR) of primary breast cancer to neoadjuvant chemotherapy (NAC). The key secondary objective was to correlate SUV with the proliferation marker Ki-67 at baseline and after NAC.

METHODS

This prospective, multicenter phase II study did not specify the therapeutic regimen, thus, NAC varied among centers. All evaluable patients underwent (18)F-FLT PET/CT at baseline (FLT1) and after 1 cycle of NAC (FLT2); 43 patients were imaged at FLT1, FLT2, and after NAC completion (FLT3). The percentage change in maximum SUV (%ΔSUVmax) between FLT1 and FLT2 and FLT3 was calculated for the primary tumors. The predictive value of ΔSUVmax for pCR was determined using receiver-operating-characteristic curve analysis. The correlation between SUVmax and Ki-67 was also assessed.

RESULTS

Fifty-one of 90 recruited patients (median age, 54 y; stage IIA-IIIC) met the eligibility criteria for the primary objective analysis, with an additional 22 patients totaling 73 patients for secondary analyses. A pCR in the primary breast cancer was achieved in 9 of 51 patients. NAC resulted in a significant reduction in %SUVmax (mean Δ, 39%; 95% confidence interval, 31-46). There was a marginal difference in %ΔSUVmax_FLT1-FLT2 between pCR and no-pCR patient groups (Wilcoxon 1-sided P = 0.050). The area under the curve for ΔSUVmax in the prediction of pCR was 0.68 (90% confidence interval, 0.50-0.83; Delong 1-sided P = 0.05), with slightly better predictive value for percentage mean SUV (P = 0.02) and similar prediction for peak SUV (P = 0.04). There was a weak correlation with pretherapy SUVmax and Ki-67 (r = 0.29, P = 0.04), but the correlation between SUVmax and Ki-67 after completion of NAC was stronger (r = 0.68, P < 0.0001).

CONCLUSION

(18)F-FLT PET imaging of breast cancer after 1 cycle of NAC weakly predicted pCR in the setting of variable NAC regimens. Posttherapy (18)F-FLT uptake correlated with Ki-67 on surgical specimens. These results suggest some efficacy of (18)F-FLT as an indicator of early therapeutic response of breast cancer to NAC and support future multicenter studies to test (18)F-FLT PET in a more uniformly treated patient population.

Role of positron emission tomography for the monitoring of response to therapy in breast cancer

This review considers the potential utility of positron emission tomography (PET) tracers in the setting of response monitoring in breast cancer, with a special emphasis on glucose metabolic changes assessed with (18)F-fluorodeoxyglucose (FDG). In the neoadjuvant setting of breast cancer, the metabolic response can predict the final complete pathologic response after the first cycles of chemotherapy. Because tumor metabolic behavior highly depends on cancer subtype, studies are ongoing to define the optimal metabolic criteria of tumor response in each subtype. The recent multicentric randomized AVATAXHER trial has suggested, in the human epidermal growth factor 2-positive subtype, a clinical benefit of early tailoring the neoadjuvant treatment in women with poor metabolic response after the first course of treatment. In the bone-dominant metastatic setting, there is increasing clinical evidence that FDG-PET/computed tomography (CT) is the most accurate imaging modality for assessment of the tumor response to treatment when both metabolic information and morphologic information are considered. Nevertheless, there is a need to define standardized metabolic criteria of response, including the heterogeneity of response among metastases, and to evaluate the costs and health outcome of FDG-PET/CT compared with conventional imaging. New non-FDG radiotracers highlighting specific molecular hallmarks of breast cancer cells have recently emerged in preclinical and clinical studies. These biomarkers can take into account the heterogeneity of tumor biology in metastatic lesions. They may provide valuable clinical information for physicians to select and monitor the effectiveness of novel therapeutics targeting the same molecular pathways of breast tumor.

The combination of FDG PET and dynamic contrast-enhanced MRI improves the prediction of disease-free survival in patients with advanced breast cancer after the first cycle of neoadjuvant chemotherapy

PURPOSE

The aim of this study was to investigate the potential of FDG PET/CT and MRI in predicting disease-free survival (DFS) after neoadjuvant chemotherapy (NAC) and surgery in patients with advanced breast cancer.

METHODS

The analysis included 54 women with advanced breast cancer. All patients received three cycles of NAC, underwent curative surgery, and then received three cycles of additional chemotherapy. Before and after the first cycle of NAC, all patients underwent sequential PET/CT and MRI. All patients were analysed using a diverse range of parameters. including maximal standardized uptake value (SUV), percent change in SUV (ΔSUV), initial slope of the enhancement curve (MRslope), apparent diffusion coefficient (ADC), tumour size, change in MRslope (ΔMRslope), change in ADC (ΔADC), change in tumour size (Δsize) and other clinicopathological parameters]. The relationships between covariates and DFS after surgery were analysed using the Kaplan-Meier method and the multivariate Cox proportional hazards model. Time-dependent receiver operating characteristic curves were used to determine the optimal cut-off values of imaging parameters for DFS.

RESULTS

Of the 54 patients, 13 (24 %) experienced recurrence at a median follow-up of 38 months (range 25 - 45 months). Univariate and multivariate analyses showed that a lesser decline in SUV, a lesser decline in MRslope, a lesser increase in ADC, and ER negativity were significantly associated with a poorer DFS (P = 0.0006, ΔSUV threshold -41 %; P = 0.0016, ΔMRslope threshold -6 %; P = 0.011, ΔADC threshold 11 %; and P = 0.0086, ER status, respectively). Patients with a combination of ΔSUV >-41 % and ΔMRslope >-6 % showed a significantly higher recurrence rate (77.8 %) than the remaining of patients (13.3 %, P < 0.0001).

CONCLUSION

Functional parameters of both FDG PET and MRI after the first cycle of NAC are useful for predicting DFS in patients with advanced breast cancer. This approach could lead to an improvement in patient care because ineffective NAC agents could be avoided and more aggressive therapy could be used in high-risk patients.

Clinical application of 18F-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in breast cancer

Positron emission tomography (PET)/computed tomography (CT) is not suited for primary diagnostics of breast tumours and it cannot replace sentinel lymph node technique in determining metastases to the axilla. PET/CT has a high sensitivity and specificity regarding the detection of loco-regional recurrence and metastases to mediastinal and internal mammary lymph nodes, as well as distant metastases. Whether the method can replace conventional methods, or be a supplement when this is non-conclusive, remains unresolved. PET/CT cannot be recommended for routine follow-up but is recommended in patients with suspected relapse when conventional imaging has given equivocal results. PET/CT can be applied to confirm isolated loco-regional relapse or metastatic lesion detected by conventional imaging. PET/CT has a high sensitivity for detecting response to treatment, but a low specificity calls for cautions. Further investigations into the use of PET/CT to predict and monitor response are warranted, before this approach may find its way into a clinical setting. In the future, PET/CT will probably find increasing use in treatment planning and evaluation of patients with breast cancer.

Early assessment of breast cancer response to neoadjuvant chemotherapy by semi-quantitative analysis of high-temporal resolution DCE-MRI: preliminary results

PURPOSE

To evaluate whether semi-quantitative analysis of high temporal resolution dynamic contrast-enhanced MRI (DCE-MRI) acquired early in treatment can predict the response of locally advanced breast cancer (LABC) to neoadjuvant chemotherapy (NAC).

MATERIALS AND METHODS

As part of an IRB-approved prospective study, 21 patients with LABC provided informed consent and underwent high temporal resolution 3T DCE-MRI before and after 1cycle of NAC. Using measurements performed by two radiologists, the following parameters were extracted for lesions at both examinations: lesion size (short and long axes, in both early and late phases of enhancement), radiologist's subjective assessment of lesion enhancement, and percentages of voxels within the lesion demonstrating progressive, plateau, or washout kinetics. The latter data were calculated using two filters, one selecting for voxels enhancing ≥50% over baseline and one for voxels enhancing ≥100% over baseline. Pretreatment imaging parameters and parameter changes following cycle 1 of NAC were evaluated for their ability to discriminate patients with an eventual pathological complete response (pCR).

RESULTS

All 21 patients completed NAC followed by surgery, with 9 patients achieving a pCR. No pretreatment imaging parameters were predictive of pCR. However, change after cycle 1 of NAC in percentage of voxels demonstrating washout kinetics with a 100% enhancement filter discriminated patients with an eventual pCR with an area under the receiver operating characteristic curve (AUC) of 0.77. Changes in other parameters, including lesion size, did not predict pCR.

CONCLUSION

Semi-quantitative analysis of high temporal resolution DCE-MRI in patients with LABC can discriminate patients with an eventual pCR after one cycle of NAC.

Diagnostic and prognostic application of positron emission tomography in breast imaging: emerging uses and the role of PET in monitoring treatment response

Positron emission tomography (PET) is an imaging modality that using radiotracers, permits real-time dynamic monitoring of biologic processes such as cell metabolic behavior and proliferation, and has proven useful as a research tool for understanding tumor biology. While it does not have a well-defined role in breast cancer for the purposes of screening, diagnosis, or prognosis, emerging PET technologies and uses could expand the applications of PET in breast cancer. Positron emission mammography may provide an alternative adjunct imaging modality for the screening and diagnosis of high-risk patients unable to tolerate MRI. The development of radiotracers with the ability to measure hormonal activity could provide a non-invasive way to assess hormone receptor status and functionality. Finally, the role of PET technologies in monitoring early treatment response may prove particularly useful to research involving new therapeutic interventions.

The maximum standardized uptake value of 18 F-FDG PET scan to determine prognosis of hormone-receptor positive metastatic breast cancer

Background

Whether PET scan maximum standard uptake value (SUVmax) could differentiate luminal A from luminal B and help predict the survival of metastatic breast cancer (MBC) patients with luminal subtype is still unknown and need to be investigated.

Methods

305 MBC patients with luminal subtypes were screened with PET/CT. Eligible patients were prospectively followed up.

Results

In total, 134 patients were eligible for this study. SUVmax was significantly related to the number of metastatic sites and presence of visceral metastasis on univariate analysis. SUVmax could not effectively differentiate patients with luminal A from luminal B subtype. Although luminal subtype at diagnosis could predict the relapse-free interval, it could not predict progression-free survival (PFS) or overall survival (OS) after developing relapse. In contrast, SUVmax was predictive of both PFS and OS and this effect was maintained in multivariate COX regression model.

Conclusions

SUVmax of MBC did not correlate with molecular subtypes of primary tumor. While molecular subtype may be a valuable prognostic factor at primary diagnosis of breast cancer, the SUVmax, rather than molecular subtype, does have a potential to predict independently in multivariate analysis for the PFS and OS in patients with metastatic disease of luminal subtype.

Preoperative systemic therapy in locoregional management of early breast cancer: highlights from the Kyoto Breast Cancer Consensus Conference

Data reviewed at the Kyoto Breast Cancer Consensus Conference (KBCCC) showed that preoperative systemic therapy (PST) could optimize surgery through the utilization of information relating to pre- and post-PST tumor stage, therapeutic sensitivity, and treatment-induced changes in the biological characteristics of the tumor. As such, it was noted that the biological characteristics of the tumor, such as hormone receptors, human epidermal growth factor receptor-2, histological grade, cell proliferative activity, mainly defined by the Ki67 labeling index, and the tumor's multi-gene signature, should be considered in the planning of both systemic and local therapy. Furthermore, the timing of axillary sentinel lymph node diagnosis (i.e., before or after the PST) was also noted to be critical in that it may influence the likelihood of axillary preservation, even in node positive cases. In addition, axillary diagnosis with ultrasound and concomitant fine needle aspiration cytology or core needle biopsy (CNB) was reported to contribute to the construction of a treatment algorithm for patient-specific or individualized axillary surgery. Following PST, planning for breast surgery should therefore be based on tumor subtype, tumor volume and extent, therapeutic response to PST, and patient preference. Nomograms for predicting nodal status and drug sensitivity were also recognized as a tool to support decision-making in the selection of surgical treatment. Overall, review of data at the KBCCC showed that PST increases the likelihood of patients receiving localized surgery and individualized treatment regimens.