Accuracy of the Combination of Mammography and Sonography in Predicting Tumor Response in Breast Cancer Patients After Neoadjuvant Chemotherapy

Evaluation of Treatment Response in Patients with Breast Cancer

Breast cancer (BC) remains one of the leading causes of death among women. The management and outcome in BC are strongly influenced by a multidisciplinary approach, which includes available treatment options and different imaging modalities for accurate response assessment. Among breast imaging modalities, MR imaging is the modality of choice in evaluating response to neoadjuvant therapy, whereas F-18 Fluorodeoxyglucose positron emission tomography, conventional computed tomography (CT), and bone scan play a vital role in assessing response to therapy in metastatic BC. There is an unmet need for a standardized patient-centric approach to use different imaging methods for response assessment.

Role of 99mTc-sestamibi Scintimammography in Predicting Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer: A Prospective Study

Background

Neoadjuvant chemotherapy (NACT) is the first line of management for locally advanced breast cancer (LABC). However, chemoresistance is prevalent in 18%-50% of the cases. One of the important and most studied causes of chemoresistance is P-glycoprotein (Pgp) expression. 99mTc-sestamibi scintimammography may serve as a useful imaging tool to predict Pgp expression, thereby response to NACT.

Aim

The aim was to study the role of 99mTc-sestamibi scintimammography in predicting response to NACT in treatment-naive, biopsy-proven LABC patients.

Materials and Methods

99mTc-sestamibi scintimammography (early and delayed images) was performed on a total of 34 patients. Eight patients were lost to follow-up, and only 26 (25 females and 1 male) patients were available for final analysis, with a mean age of 49.7 ± 10.7 years. 99mTc-sestamibi washout rate (WOR) (%) and T/B buildup were calculated. Pre-NACT and Post-NACT tumor sizes were measured clinically, and a % decrease in tumor size was calculated. The WOR and T/B buildup values were correlated with the % decrease in tumor size.

Results

We found a statistically significant negative correlation between WOR (%) and % decrease in tumor size and a statistically significant positive correlation between T/B buildup and % decrease in tumor size. Furthermore, we found a positive correlation between the early T/B ratio and the Ki-67 index (P = 0.22).

Conclusion

Early categorization of responders and nonresponders can help in optimal therapy planning. 99mTc-sestamibi scintimammography can serve as an imaging marker for Pgp expression, thereby predicting clinical response to NACT in LABC patients. Further studies with larger sample sizes are warranted to consolidate the above findings.

Predicting Pathological Complete Response in Breast Cancer After Two Cycles of Neoadjuvant Chemotherapy by Tumor Reduction Rate: A Retrospective Case-Control Study

PURPOSE

We aimed to identify effectiveness-associated indicators and evaluate the optimal tumor reduction rate (TRR) after two cycles of neoadjuvant chemotherapy (NAC) in patients with invasive breast cancer.

METHODS

This retrospective case-control study included patients who underwent at least four cycles of NAC at the Department of Breast Surgery between February 2013 and February 2020. A regression nomogram model for predicting pathological responses was constructed based on potential indicators.

RESULTS

A total of 784 patients were included, of whom 170 (21.68%) reported pathological complete response (pCR) after NAC and 614 (78.32%) had residual invasive tumors. The clinical T stage, clinical N stage, molecular subtype, and TRR were identified as independent predictors of pCR. Patients with a TRR > 35% were more likely to achieve pCR (odds ratio, 5.396; 95% confidence interval [CI], 3.299-8.825). The receiver operating characteristic (ROC) curve was plotted using the probability value, and the area under the ROC curve was 0.892 (95% CI, 0.863-0.922).

CONCLUSION

TRR > 35% is predictive of pCR after two cycles of NAC, and an early evaluation model using a nomogram based on five indicators, age, clinical T stage, clinical N stage, molecular subtype, and TRR, is applicable in patients with invasive breast cancer.

Construction and validation of a personalized nomogram of ultrasound for pretreatment prediction of breast cancer patients sensitive to neoadjuvant chemotherapy

OBJECTIVE

To construct a combined radiomics model based on pre-treatment ultrasound for predicting of advanced breast cancers sensitive to neoadjuvant chemotherapy (NAC).

METHODS

A total of 288 eligible breast cancer patients who underwent NAC before surgery were enrolled in the retrospective study cohort. Radiomics features reflecting the phenotype of the pre-NAC tumors were extracted. With features selected using the least absolute shrinkage and selection operator (LASSO) regression, radiomics signature (Rad-score) was established based on the pre-NAC ultrasound. Then, radiomics nomogram of ultrasound (RU) was established on the basis of the best radiomic signature incorporating independent clinical features. The performance of RU was evaluated in terms of calibration curve, area under the curve (AUC), and decision curve analysis (DCA).

RESULTS

Nine features were selected to construct the radiomics signature in the training cohort. Combined with independent clinical characteristics, the performance of RU for identifying Grade 4-5 patients was significantly superior than the clinical model and Rad-score alone (p < 0.05, as per the Delong test), which achieved an AUC of 0.863 (95% CI, 0.814-0.963) in the training group and 0.854 (95% CI, 0.776-0.931) in the validation group. DCA showed that this model satisfactory clinical utility, suggesting its robustness as a response predictor.

CONCLUSION

This study demonstrated that RU has a potential role in predicting drug-sensitive breast cancers.

ADVANCES IN KNOWLEDGE

Aiming at early detection of Grade 4-5 breast cancer patients, the radiomics nomogram based on ultrasound has been approved as a promising indicator with high clinical utility. It is the first application of ultrasound-based radiomics nomogram to distinguish drug-sensitive breast cancers.

Staging Breast Cancer with MRI, the T. A Key Role in the Neoadjuvant Setting

Breast cancer (BC) is the most common cancer among women worldwide. Neoadjuvant chemotherapy (NACT) indications have expanded from inoperable locally advanced to early-stage breast cancer. Achieving a pathological complete response (pCR) has been proven to be an excellent prognostic marker leading to better disease-free survival (DFS) and overall survival (OS). Although diagnostic accuracy of MRI has been shown repeatedly to be superior to conventional methods in assessing the extent of breast disease there are still controversies regarding the indication of MRI in this setting. We intended to review the complex literature concerning the tumor size in staging, response and surgical planning in patients with early breast cancer receiving NACT, in order to clarify the role of MRI. Morphological and functional MRI techniques are making headway in the assessment of the tumor size in the staging, residual tumor assessment and prediction of response. Radiomics and radiogenomics MRI applications in the setting of the prediction of response to NACT in breast cancer are continuously increasing. Tailored therapy strategies allow considerations of treatment de-escalation in excellent responders and avoiding or at least postponing breast surgery in selected patients.

Breast cancer resistance to chemotherapy: When should we suspect it and how can we prevent it?

Chemotherapy is an essential treatment for breast cancer, inducing cancer cell death. However, chemoresistance is a problem that limits the effectiveness of chemotherapy. Many factors influence chemoresistance, including drug inactivation, changes in drug targets, overexpression of ABC transporters, epithelial-to-mesenchymal transitions, apoptotic dysregulation, and cancer stem cells. The effectiveness of chemotherapy can be assessed clinically and pathologically. Clinical response evaluation is based on physical examination or imaging (mammography, ultrasonography, computed tomography scan, or magnetic resonance imaging) and includes tumor size changes after chemotherapy. Pathological response evaluation is a method based on tumor residues in histopathological preparations. We should be suspicious of chemoresistance if there are no significant changes clinically according to the Response Evaluation Criteria in Solid Tumors and World Health Organization criteria or pathological changes according to the Miller and Payne criteria, especially after 2–3 cycles of chemotherapy treatments. Chemoresistance is mostly detected after the administration of chemotherapy drugs. No reliable parameters or biomarkers can predict chemotherapy responses appropriately and effectively. Well-known parameters such as cancer type, grade, subtype, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, Ki-67, and MDR-1/P-gP have been used for selecting chemotherapy regimens. Some new methods for predicting chemoresistance include chemosensitivity and chemoresistance assays, multigene expressions, and positron emission tomography assays. The latest approaches are based on evaluation of molecular processes and the metabolic activity of cancer cells. Some methods for preventing chemoresistance include using the right regimen, using some combination of chemotherapy methods, conducting adequate monitoring, and using drugs that could prevent the emergence of multidrug resistance.

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Chemotherapy is an essential treatment in the management of breast cancer.

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Chemotherapy is carried out based on the selection of regimens for the specific individual and tumor characteristics.

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Combination therapy, monitoring, and evaluation are used to prevent chemoresistance.

Response to Induction Neoadjuvant Hormonal Therapy Using Upfront 21-Gene Breast Recurrence Score Assay-Results From the SAFIA Phase III Trial

Luminal, human epidermal growth factor receptor 2–negative breast cancer represents the most common subtype of breast malignancies. Neoadjuvant strategies of operable breast cancer are mostly based on chemotherapy, whereas it is not completely understood which patients might benefit from neoadjuvant hormone therapy (NAHT).

Feasibility of ABUS as an Alternative to Handheld Ultrasound for Response Control in Neoadjuvant Breast Cancer Treatment

INTRODUCTION

The Invenia Automated Breast Ultrasound Screening (ABUS) is indicated as an adjunct to mammography for breast cancer screening in asymptomatic women with high-density breast tissue. ABUS provides time-efficient evaluation of the 3-dimensional recordings within 3 to 6 minutes. The role and advantages of ABUS in everyday clinical practice, especially in routine examination during neoadjuvant chemotherapy (NACT), is not clear. The aim of this monocentric, noninterventional retrospective study is to evaluate the use of ABUS in patients who are under NACT treatment for response control.

METHODS

Regular sonographic response check with handheld ultrasound (HHUS) examination and with ABUS were conducted in 83 women who underwent NACT. The response controls were conducted every 3 to 6 weeks during NACT. The handheld sonography was performed with GE Voluson S8. Handheld sonographic measurements and ABUS measurements were compared with the final pathologic tumor size.

RESULTS

There was no statistical difference between the measurements with HHUS examination or ABUS compared with final pathologic tumor size (P = .47). The average difference from ABUS measured tumor size to final pathologic tumor size was 9.8 mm. The average difference from handheld measured tumor size to final pathologic tumor size was 9/3 mm. Both the specificity of ABUS and HHUS examination in predicting pathologic complete remission was 100%.

CONCLUSION

ABUS seems to be a suitable method to conduct response control in neoadjuvant breast cancer treatment. ABUS may facilitate preoperative planning and offers remarkable time saving for physicians compared with HHUS examination and thus should be considered for clinical practice.

Neoadjuvant breast cancer treatment response; tumor size evaluation through different conventional imaging modalities in the NeoDense study

BACKGROUND

Neoadjuvant chemotherapy (NACT) is offered to an increasing number of breast cancer (BC) patients, and comprehensive monitoring of treatment response is of utmost importance. Several imaging modalities are available to follow tumor response, although likely to provide different clinical information. We aimed to examine the association between early radiological response by three conventional imaging modalities and pathological complete response (pCR). Further, we investigated the agreement between these modalities pre-, during, and post-NACT, and the accuracy of predicting pathological residual tumor burden by these imaging modalities post-NACT.

MATERIAL AND METHODS

This prospective Swedish cohort study included 202 BC patients assigned to NACT (2014-2019). Breast imaging with clinically used modalities: mammography, ultrasound, and tomosynthesis was performed pre-, during, and post-NACT. We investigated the agreement of tumor size by the different imaging modalities, and their accuracy of tumor size estimation. Patients with a radiological complete response or radiological partial response (≥30% decrease in tumor diameter) during NACT were classified as radiological early responders.

RESULTS

Patients with an early radiological response by ultrasound had 2.9 times higher chance of pCR than early radiological non-responders; the corresponding relative chance for mammography and tomosynthesis tumor size measures was 1.8 and 2.8, respectively. Post-NACT, each modality, separately, could accurately estimate tumor size (within 5 mm margin compared to pathological evaluation) in 43-46% of all tumors. The diagnostic precision in predicting pCR post-NACT was similar between the three imaging modalities; however, tomosynthesis had slightly higher specificity and positive predictive values.

CONCLUSION

Breast imaging modalities correctly estimated pathological tumor size in less than half of the tumors. Based on this finding, predicting residual tumor size post-NACT is challenging using conventional imaging. Patients with early radiological non-response might need improved monitoring during NACT and be considered for changed treatment plans.

A Novel Marker, Based on Ultrasound Tomography, for Monitoring Early Response to Neoadjuvant Chemotherapy

OBJECTIVE

To evaluate the combination of tumor volume and sound speed as a potential imaging marker for assessing neoadjuvant chemotherapy (NAC) response.

METHODS

This study was carried out under an IRB-approved protocol (written consent required). Fourteen patients undergoing NAC for invasive breast cancer were examined with ultrasound tomography (UST) throughout their treatment. The volume (V) and the volume-averaged sound speed (VASS) of the tumors and their changes were measured for each patient. Time-dependent response curves of V and VASS were constructed individually for each patient and then as averages for the complete versus partial response groups in order to characterize differences between the two groups. Differences in group means were assessed for statistical significance using t-tests. Differences in shapes of group curves were evaluated with Kolmogorov-Smirnoff tests.

RESULTS

On average, tumor volume and sound speed in the partial response group showed a gradual decline in the first 60 days of treatment, while the complete response group showed a much steeper decline (P < 0.05). The shapes of the response curves of the two groups, corresponding to the entire treatment period, were also found to be significantly different (P < 0.05). Furthermore, large simultaneous drops in volume and sound speed in the first 3 weeks of treatment were characteristic only of the complete responders (P < 0.05).

CONCLUSION

This study demonstrates the feasibility of using UST to monitor NAC response, warranting future studies to better define the potential of UST for noninvasive, rapid identification of partial versus complete responders in women undergoing NAC.

Defining radiologic complete response using a correlation of presurgical ultrasound and mammographic localization findings with pathological complete response following neoadjuvant chemotherapy in breast cancer

PURPOSE

Breast cancer affects a significant number of patients younger than 40 years in the Gulf and breast conservative treatment is highly preferred. Pathological complete response (pCR) following neoadjuvant chemotherapy is increasingly being observed with the new chemotherapy agents. Although MRI is more accurate in such evaluations, digital mammography and high-resolution ultrasound (US) which are less expensive may accurately predict pCR which is the focus of this study.

METHODS

A 6-year retrospective study of 93 breast cancer cases who had neoadjuvant chemotherapy and had presurgical radiological localization was carried out. Forty-five had US localization while 48 underwent mammographic localization when US failed to define any residual mass. Radiologic complete response (rCR) was defined as absence of mass with only postbiopsy clip overlying normal breast parenchyma pattern in US and in mammography (clip sign). Mass or abnormal parenchymal pattern was considered as residual tumor. The pathology reports of pCR or not with background changes were recorded.

RESULTS

Ultrasound localization correctly predicted 42 out of 43 pathologic masses with 98 % accuracy. Mammographic localization correctly predicted 40 out of 43 pCR with 93 % accuracy. The best responders were triple negative and HER2 positive hormone negative breast cancer.

CONCLUSION

The study defines radiologic complete response (rCR) as absence of a mass with the postbiopsy tissue marker overlying a normal-looking breast parenchyma in both ultrasound and mammographic evaluation. A correlation of 93 % was found with pCR. The few false negative cases were associated with overlying dense breast and possibly post treatment reaction. Allocation of a BI-RADS category for rCR is suggested.

Early prediction of pathologic response to neoadjuvant treatment of breast cancer: use of a cell-loss metric based on serum thymidine kinase 1 and tumour volume

Background

After neoadjuvant chemotherapy of breast cancer pathologic complete response (pCR) indicates a favorable prognosis. Among non-selected patients, pCR is, however, achieved in only 10–30%. Early evaluation of tumour response to treatment would facilitate individualized therapy, with ineffective chemotherapy interrupted or changed. The methodology for this purpose is still limited. Tumour imaging and analysis of macromolecules, released from disrupted tumour cells, are principal alternatives.

Objective

To investigate whether a metric of cell-loss, defined as the ratio between serum concentration of thymidine kinase1 (sTK1, ng x ml^− 1) and tumour volume, can be used for early prediction of pathologic response.

Methods

One hunred four women with localized breast cancer received neoadjuvant epirubicin/docetaxel in 6 cycles, supplemented with bevacizumab in cycles 3–6. The cell-loss metric was established at baseline (n = 104), 48 h after cycle 2 (n = 104) and prior to cycle 2 (n = 57). The performance of the metric was evaluated by association with pathologic tumour response at surgery 4 months later.

Results

Treatment caused a rise in sTK1, a reduction in tumour volume and a marked increase in the cell-loss metric. Patients were subdivided into quartiles according to the baseline cell-loss metric. For these groups, baseline means were 0.0016, 0.0042, 0.0062, 0.0178 units. After subtraction of baselines, means for the quartiles 48 h after treatment 2 were 0.002, 0.011, 0.030 and 0.357 units. pCR was achieved in 24/104, their distribution in the quartiles (11, 11, 23 and 46%) differed significantly (p = 0.01). In 80 patients with remaining tumour, tumour size was inversely related to the metric (p = 0.002). In 57 patients studied before treatment 2, positive and negative predictive values of the metric were 77.8 and 83.3%, compared to 40.5 and 88.7% 48 h after treatment 2.

Conclusion

A cell-loss metric, based on serum levels of TK1, released from disrupted tumour cells, and tumour volume, reveal tumour response early during neoadjuvant treatment. The metric reflect tumour properties that differ greatly between patients and determine the sensitivity to cytotoxic treatment. The findings point to the significance of cell loss for tumour growth rate. The metric should be considered in personalized oncology and in the evaluation of new therapeutic modalities.

Trial registration

PROMIX (Clinical Trials.govNCT000957125).

Early prediction of pathologic response to neoadjuvant treatment of breast cancer: use of a cell-loss metric based on serum thymidine kinase 1 and tumour volume

BACKGROUND

After neoadjuvant chemotherapy of breast cancer pathologic complete response (pCR) indicates a favorable prognosis. Among non-selected patients, pCR is, however, achieved in only 10-30%. Early evaluation of tumour response to treatment would facilitate individualized therapy, with ineffective chemotherapy interrupted or changed. The methodology for this purpose is still limited. Tumour imaging and analysis of macromolecules, released from disrupted tumour cells, are principal alternatives.

OBJECTIVE

To investigate whether a metric of cell-loss, defined as the ratio between serum concentration of thymidine kinase1 (sTK1, ng x ml^- 1) and tumour volume, can be used for early prediction of pathologic response.

METHODS

One hunred four women with localized breast cancer received neoadjuvant epirubicin/docetaxel in 6 cycles, supplemented with bevacizumab in cycles 3-6. The cell-loss metric was established at baseline (n = 104), 48 h after cycle 2 (n = 104) and prior to cycle 2 (n = 57). The performance of the metric was evaluated by association with pathologic tumour response at surgery 4 months later.

RESULTS

Treatment caused a rise in sTK1, a reduction in tumour volume and a marked increase in the cell-loss metric. Patients were subdivided into quartiles according to the baseline cell-loss metric. For these groups, baseline means were 0.0016, 0.0042, 0.0062, 0.0178 units. After subtraction of baselines, means for the quartiles 48 h after treatment 2 were 0.002, 0.011, 0.030 and 0.357 units. pCR was achieved in 24/104, their distribution in the quartiles (11, 11, 23 and 46%) differed significantly (p = 0.01). In 80 patients with remaining tumour, tumour size was inversely related to the metric (p = 0.002). In 57 patients studied before treatment 2, positive and negative predictive values of the metric were 77.8 and 83.3%, compared to 40.5 and 88.7% 48 h after treatment 2.

CONCLUSION

A cell-loss metric, based on serum levels of TK1, released from disrupted tumour cells, and tumour volume, reveal tumour response early during neoadjuvant treatment. The metric reflect tumour properties that differ greatly between patients and determine the sensitivity to cytotoxic treatment. The findings point to the significance of cell loss for tumour growth rate. The metric should be considered in personalized oncology and in the evaluation of new therapeutic modalities.

TRIAL REGISTRATION

PROMIX (Clinical Trials.govNCT000957125).

Changes in Cytokeratin 18 during Neoadjuvant Chemotherapy of Breast Cancer: A Prospective Study

BACKGROUND & OBJECTIVE

Prediction of response to neoadjuvant treatment is an important part of treatment of patients with breast cancer. This study aimed to assess changes in serum levels of Cytokeratin 18 during neoadjuvant chemotherapy in patients with locally advanced breast cancer and its association with neoadjuvant treatments.

METHODS

This research was performed on newly diagnosed breast cancer patients referred to Omid Radiotherapy Center and radiotherapy and oncology departments of Emam Reza and Ghaem hospitals, in Mashhad, Iran. Serum levels of M30 and M65 fragments of Cytokeratin 18 were measured before and 24 hours after the first course of neoadjuvant chemotherapy. Changes in serum levels of Cytokeratin 18 and its fragments and their correlation with pathologic response were analyzed.

RESULTS

Pre- and post-chemotherapy levels of M30 were respectively 223.9±18.94 and 250.7±23.92 U/L (P=0.24). For M65, these levels were respectively 301.5±313.9 and 330.2±352.2 U/L (P=0.1). Changes in M30 level during chemotherapy in patients with and without pathologic complete response were -20±92.69 and 43.1±106.5, respectively (P=0.1). For M65, these changes were respectively -247±55 and 76±240 (P=0.1). Baseline levels of M30 and M65 had no relation with menopausal status, tumor grade, hormone receptor status, Ki67 expression, molecular subtype, and stage.

CONCLUSION

Our findings showed statistically insignificant changes in the level of Caspase-cleaved- (M30) and uncleaved- (M65) cytokeratin 18 fragments (apoptotic and necrotic indicators, respectively) during neoadjuvant chemotherapy in patients with breast cancer. There was no notable relationship between tumor-related factors and either baseline levels or serum changes of CK18 fragments. Also, there was no correlation between M30/M65 level and pathologic response to neoadjuvant chemotherapy.

A Clinical Feasibility Trial for Identification of Exceptional Responders in Whom Breast Cancer Surgery Can Be Eliminated Following Neoadjuvant Systemic Therapy

OBJECTIVE

To determine the accuracy of fine-needle aspiration (FNA) and vacuum-assisted core biopsy (VACB) in assessing the presence of residual cancer in the breast after neoadjuvant systemic therapy (NST).

SUMMARY BACKGROUND DATA

Pathologic complete response (pCR) rates after NST have improved dramatically, suggesting that surgery might be avoided in some patients. Safe avoidance of surgery would require accurate confirmation of no residual invasive/in situ carcinoma.

METHODS

Forty patients with T1-3N0-3 triple-negative or HER2-positive cancer receiving NST were enrolled in this single-center prospective trial. Patients underwent ultrasound-guided or mammography-guided FNA and VACB of the initial breast tumor region before surgery. Findings were compared with findings on pathologic evaluation of surgical specimens to determine the performance of biopsy in predicting residual breast disease after NST.

RESULTS

Median initial clinical tumor size was 3.3 cm (range, 1.2-7.0 cm); 16 patients (40%) had biopsy-proven nodal metastases. After NST, median clinical tumor size was 1.1 cm (range, 0-4.2 cm). Nineteen patients (47.5%) had a breast pCR and were concordant with pathologic nodal status in 97.5%. Combined FNA/VACB demonstrated an accuracy of 98% (95% CI, 87%-100%), false-negative rate of 5% (95% CI, 0%-24%), and negative predictive value of 95% (95% CI, 75%-100%) in predicting residual breast cancer. VACB alone was more accurate than FNA alone (P = 0.011).

CONCLUSIONS

After NST, image-guided FNA/VACB can accurately identify patients with a breast pCR. Based on these results, a prospective clinical trial has commenced in which breast surgery is omitted in patients with a breast pCR after NST according to image-guided biopsy.

Strain wave elastography in response assessment to neo-adjuvant chemotherapy in patients with locally advanced breast cancer

OBJECTIVE

The study was conducted to study the role of strain wave elastography in evaluating the response to neo-adjuvant chemotherapy (NACT) in patients with locally advanced breast cancer (LABC).

METHODS

In this Institutional review board approved study, 86 patients of LABC were investigated with strain wave elastography. Females receiving NACT had the affected breast scanned by strain wave elastography before each cycle of chemotherapy and immediately before surgery by two independent observers. Changes in elastographic parameters (size ratio, strain ratio) were documented and then compared to clinical and pathologic tumor response as evaluated after mastectomy.

RESULTS

Elastographic strain ratio parameters demonstrated high sensitivity and moderate specificity for determining response even after the first cycle of neo-adjuvant chemotherapy [97.7% sensitivity (Sn), 68.7% specificity (Sp)]. Elastographic size ratio parameters showed moderate sensitivity and specificity for response detection after second and third cycle of neo-adjuvant chemotherapy (Sn, Sp: after second cycle of NACT Sn 83.3% Sp 80%; after third cycle of NACT Sn 77.8% Sp 100%).

CONCLUSION

Strain ratio is the earliest predictor of treatment response in patients of LABC. Serial imaging with elastography has the potential to predict treatment response early during the course of NACT, which may prove vital in management of patients with breast cancer.

ADVANCES IN KNOWLEDGE

Strain wave elastography is a powerful tool to predict chemoresponse early during the course of management, thereby providing an optimal window to change treatment protocols.

Biopsy Feasibility Trial for Breast Cancer Pathologic Complete Response Detection after Neoadjuvant Chemotherapy: Imaging Assessment and Correlation Endpoints

PURPOSE

This study was designed to present the secondary imaging endpoints of the trial for evaluating mammogram (MMG), ultrasound (US) and image guided biopsy (IGBx) assessment of pathologic complete response (pCR) in breast cancer (BC) patients undergoing neoadjuvant chemotherapy (NAC).

METHODS

Patients with T1-3, N0-3, M0 triple-negative or HER2-positive BC who received NAC were enrolled in an Institutional Review Board-approved prospective, clinical trial. Patients underwent US and MMG at baseline and after NAC. Images were evaluated for residual abnormality and to determine modality for IGBx [US-guided (USG) or stereotactic guided (SG)]. Fine-needle aspiration and 9-G, vacuum-assisted core biopsy (VACBx) of tumor bed was performed after NAC and was compared with histopathology at surgery.

RESULTS

Forty patients were enrolled. Median age was 50.5 (range 26-76) years; median baseline tumor size was 2.4 cm (range 0.8-6.3) and 1 cm (range 0-5.5) after NAC. Nineteen patients had pCR: 6 (32%) had residual Ca²⁺ presurgery, 5 (26%) residual mass, 1 (5%) mass with calcifications, and 7 (37%) no residual imaging abnormality. Sensitivity, specificity, and accuracy of US, MMG, and IGBx for pCR were 47/95/73%, 53/90/73%, and 100/95/98%, respectively. Twenty-five (63%) patients had SGBx and 15 (37%) had US-guided biopsy (USGBx). Median number of cores was higher with SGBx (12, range 6-14) than with USGBx (8, range 4-12), p < 0.002. Positive predictive value for pCR was significantly higher for SG VACBx than for USG VACBx (100 vs. 60%, p < 0.05).

CONCLUSIONS

SG VACBx is the preferred IGBx modality for identifying patients with pCR for trials testing the safety of eliminating surgery.

Baseline factors predicting a response to neoadjuvant chemotherapy with implications for non-surgical management of triple-negative breast cancer

BACKGROUND

Patients with triple-negative breast cancer (TNBC) and a pathological complete response (pCR) after neoadjuvant chemotherapy may be suitable for non-surgical management. The goal of this study was to identify baseline clinicopathological variables that are associated with residual disease, and to evaluate the effect of neoadjuvant chemotherapy on both the invasive and ductal carcinoma in situ (DCIS) components in TNBC.

METHODS

Patients with TNBC treated with neoadjuvant chemotherapy followed by surgical resection were identified. Patients with a pCR were compared with those who had residual disease in the breast and/or lymph nodes. Clinicopathological variables were analysed to determine their association with residual disease.

RESULTS

Of the 328 patients, 36·9 per cent had no residual disease and 9·1 per cent had residual DCIS only. Patients with residual disease were more likely to have malignant microcalcifications (P = 0·023) and DCIS on the initial core needle biopsy (CNB) (P = 0·030). Variables independently associated with residual disease included: DCIS on CNB (odds ratio (OR) 2·46; P = 0·022), T2 disease (OR 2·40; P = 0·029), N1 status (OR 2·03; P = 0·030) and low Ki-67 (OR 2·41; P = 0·083). Imaging after neoadjuvant chemotherapy had an accuracy of 71·7 (95 per cent c.i. 66·3 to 76·6) per cent and a negative predictive value of 76·9 (60·7 to 88·9) per cent for identifying residual disease in the breast and lymph nodes. Neoadjuvant chemotherapy did not eradicate the DCIS component in 55 per cent of patients.

CONCLUSION

The presence of microcalcifications on imaging and DCIS on initial CNB are associated with residual disease after neoadjuvant chemotherapy in TNBC. These variables can aid in identifying patients with TNBC suitable for inclusion in trials evaluating non-surgical management after neoadjuvant chemotherapy.

Is Breast Surgery Necessary for Breast Carcinoma in Complete Remission Following Neoadjuvant Chemotherapy?

The likelihood of pathological complete remission (pCR) of breast cancer following neoadjuvant chemotherapy (NACT) is increasing; most of all in the triple negative and HER2 positive tumour subgroups. The question thus arises whether or not breast surgery is necessary when there is complete remission after NACT, and whether it provides any improvement of the oncological treatment result when tumour is no longer detectable. Avoiding surgery and possibly even radiotherapy would only be conceivable on the basis of a reliable diagnosis of pCR without operating. Current imaging does not achieve the necessary sensitivity and specificity to assure the diagnosis of pathological complete remission. Further studies are therefore required to determine which methods are best able to evaluate tumour response to NACT. Studies on image-guided, minimally invasive biopsies after NACT have delivered first promising results towards diagnosing pCR before surgery and could provide the basis for further studies on the possibility of avoiding surgery in this specific patient collective.

Nonoperative Management for Invasive Breast Cancer After Neoadjuvant Systemic Therapy: Conceptual Basis and Fundamental International Feasibility Clinical Trials

With current advances in neoadjuvant systemic therapy (NST) and improved breast imaging, the potential of nonoperative therapy for invasive breast cancer has emerged as a viable option when utilizing meticulous image-guided percutaneous biopsy to document pathologic complete response. Feasibility clinical trials utilizing this approach are being performed by teams of investigators from single and multicenter/cooperative groups around the world. Imaging alone after NST lacks sufficient sensitivity and specificity in predicting pCR and therefore cannot be utilized for clinical selection of patients for omission of surgery. Imaging with adequate sampling after NST of the residual lesions (or around the remaining clip if a complete radiologic response occurs) appears to be essential in selecting patients with pCR to lower the false-negative rates based on initial reported feasibility studies to identify pCR without surgery that range from 5 to 49%. In this manuscript, recently completed, ongoing, and planned clinical feasibility trials and a new omission of surgery trial are described. Drastic rethinking of all diagnostic and therapeutic management strategies that are ordinarily utilized for patients who receive standard breast cancer surgery is required. A roadmap of essential questions and issues that will have to be resolved as the field of nonoperative breast cancer management advances is described in detail.

Tumor Staging and Grading: A Primer

Cancer staging and grading are used to predict the clinical behavior of malignancies, establish appropriate therapies, and facilitate exchange of precise information between clinicians. The internationally accepted criterion for cancer staging, the tumor-node-metastasis (TNM) system, includes: (1) tumor size and local growth (T), (2) extent of lymph node metastases (N), and (3) occurrence of distant metastases (M). Clinical stage is established before initiation of therapy and is determined by physical examination, laboratory findings, and imaging studies. Pathologic stage is determined following surgical exploration of disease and histologic examination of tissue. The TNM classification system has evolved over 70 years to accommodate increasing knowledge about cancer biology. Molecular technologies such as genomic and proteomic profiling of tumors could eventually be incorporated into the TNM staging system. This chapter describes the current TNM system using breast, lung, ovarian, and prostate cancer examples.

Relevance of Pathological Complete Response after Neoadjuvant Therapy for Breast Cancer

Breast cancer is a heterogeneous disease, and the different biological subtypes have different prognostic impacts. Neoadjuvant trials have recently become popular as they offer several advantages compared to traditional adjuvant trials. Studies have shown that patients who achieve pathological complete response (pCR) after neoadjuvant treatment have a better long-term outcome. Consequently, increasing the rate of pCR became the end point of neoadjuvant trials with the expectation of translation into improved survival. However, the definition of pCR has lacked uniformity, and the prognostic impact of achievement of pCR on survival in different breast cancer subtypes is uncertain. In this review, we present the controversies associated with the use of pCR as an end point in neoadjuvant trials.

Assessment of Residual Disease With Molecular Breast Imaging in Patients Undergoing Neoadjuvant Therapy: Association With Molecular Subtypes

BACKGROUND

Assessment of residual disease after neoadjuvant therapy for breast cancer is an ongoing challenge of breast imaging. This study evaluates the accuracy of a novel dedicated system for molecular breast imaging (MBI) composed of the new generation of cadmium zinc telluride detectors in assessing residual disease after neoadjuvant therapy in patients with breast cancer.

PATIENTS AND METHODS

Clinical data, imaging, surgical, and pathological findings of 51 women with breast cancer undergoing neoadjuvant therapy were recorded. MBI findings were correlated with surgical pathology results. Accuracy of MBI in predicting complete pathological response and size of residual disease was assessed according to molecular subtypes.

RESULTS

The size of the largest focus of uptake on MBI correlated with the largest dimension measured on pathology (r = 0.55; P < .001). This correlation was stronger for triple negative and HER2/neu positive subtypes (r = 0.92 and 0.62, respectively). Sixteen patients (31%) had complete pathological response. The sensitivity and specificity of MBI for detecting residual disease were 83% (95% confidence interval [CI], 66-93) and 69% (95% CI, 42-88), respectively. For triple negative or HER2/neu positive disease the sensitivity and specificity were 88% (95% CI, 62-98) and 75% (95% CI, 43-93), respectively.

CONCLUSION

The accuracy of MBI in assessing residual disease after neoadjuvant treatment might be related to the molecular subtype. Accuracy is highest in the triple negative and HER2/neu positive subtypes.

Morphological and pathological response in primary systemic therapy of patients with breast cancer and the prediction of disease free survival: a single center observational study

Aim

To identify breast cancer subtypes likely to respond to primary systemic therapy (PST or neoadjuvant therapy) and to assess the accuracy of physical examination (PE) and breast ultrasonography (US) in evaluating and predicting residual size of breast carcinoma following PST.

Methods

116 patients who received at least two cycles of PST between 1998 and 2009 were selected from a prospectively collected clinical database. Radiological assessment was done by mammography and US. Prior to PST, tumors were subclassified according to core biopsy (NCB) and/or fine-needle aspiration-based immunohistochemical profiles of NCB. Pathological response rates were assessed following the surgeries by using Chevallier classification. Tumor measurements by PE and US were obtained before and after PST. Different clinical measurements were compared with histological findings. Disease-free survival (DFS) was assessed.

Results

Pathological complete remission (pCR = Chevallier I/II) was observed in 25 patients (21.5%), 44% of whom had triple negative histology, 28% Her2 positive and 76% had high-grade tumor. Of 116 patients, 24 received taxane-based PST, 48 combined taxane + anthracycline treatment, 8 trastuzumab combinations, 21 anthracycline-based treatments, and 15 other treatments. In the taxane treated group, the pCR rate was 30%, in the taxane + anthracycline group 25%, in the anthracycline group 9.5%, and in trastuzumab group 37.5%. After PST, PE and US were both significantly associated with pathology (P < 0.001 and P = 0.004, respectively). Concerning OS, significant difference was observed between the Chevallier III and IV group (P = 0.031) in favor of Chevallier III group. In the pCR group, fewer events were observed during the follow-up period.

Conclusions

Our results show that even limited, routinely used immunohistochemical profiling of tumors can predict the likelihood of pCR to PST: patients with triple negative and Her2-positive cancers are more likely to achieve pCR to PST. Also, PE is better correlated with pathological findings than US.

Selective elimination of breast cancer surgery in exceptional responders: historical perspective and current trials

With improvements in chemotherapy regimens, targeted therapies, and our fundamental understanding of the relationship of tumor subtype and pathologic complete response (pCR), there has been dramatic improvement in pCR rates in the past decade, especially among triple-negative and human epidermal growth factor receptor 2-positive breast cancers. Rates of pCR in these groups of patients can be in the 60 % range and thus question the paradigm for the necessity of breast and nodal surgery in all cases, particularly when the patient will be receiving adjuvant local therapy with radiotherapy. Current practice for patients who respond well to neoadjuvant chemotherapy (NCT) is often to proceed with the same breast and axillary procedures as would have been offered women who had not received NCT, regardless of the apparent clinical response. Given these high response rates in defined subgroups among exceptional responders it is appropriate to question whether surgery is now a redundant procedure in their overall management. Further, definitive radiation without surgical resection with or without systemic therapy has been proven effective for several other malignant disease sites including some stages of esophageal, anal, laryngeal, prostate, cervical, and lung carcinoma. The main impediments for potential elimination of surgery have been the fact that prior and current standard and functional breast imaging methods are incapable of accurate prediction of residual disease and that integrating percutaneous biopsy of the breast primary and nodes following NCT may circumvent this issue. This article highlights historical attempts at omission of surgery following NCT in an earlier era, the current status of breast and nodal imaging to predict residual carcinoma, and ongoing and planned trials designed to identify appropriate patients who might be selected for clinical trials designed to test the safety of selected elimination of breast cancer surgery in percutaneous image-guided biopsy-proven exceptional responders to NCT.

Radiological and Pathological Predictors of Response to Neoadjuvant Chemotherapy in Breast Cancer: A Brief Literature Review

BACKGROUND

Early clinical response to neoadjuvant chemotherapy (NACT) in breast cancer correlates with pathological response at surgery. A tailored approach using biomarkers to predict response to NACT has become a research priority. Predictors of response can be divided into pathological and radiological biomarkers. Advances in gene expression profiling and diffusion-weighted MRI techniques are used to predict tumour response, and combinations thereof are the future of predicting response to NACT in early-stage breast cancer.

METHODS

We searched Medline, CINAHL and Embase databases for studies on NACT. Key words used were NACT, breast cancer, pathological* complete response, primary chemotherapy, radiological*, predictor*, gene expression and biomarkers limited to the English language. Pathological markers such as tumour subtypes, topoisomerase IIα expression, Ki67, apoptosis-related markers and gene expression profiling were included.

RESULTS

From 119 articles, 42 studies were reviewed; the majority of studies identified used pathological clinical response as an end point to NACT, whilst others used complete clinical response. Despite extensive studies, results regarding long-term survival following NACT and potential predictors are inconclusive.

CONCLUSION

Future development of a predictive model combining key pathological and radiological biomarkers could provide personalised treatment regimens that improve pathological complete response rates and longer-term outcomes.

Magnetic Resonance Imaging, Digital Mammography, and Sonography: Tumor Characteristics and Tumor Biology in Primary Setting

The use of imaging in the arena of primary treatment for breast cancer is gaining importance as a technique for assessing response to chemotherapy as well as assessing the underlying tumor biology. Both mammography and ultrasound have traditionally been used, in addition to clinical evaluation, to evaluate response to treatment although they have shed little light on the underlying biological processes. Functional magnetic resonance imaging techniques have the ability to assess response to treatments in addition to providing valuable information on changes in tumor perfusion, vascular permeability, oxygenation, cellularity, proliferation, and metabolism both at baseline and after treatment. This noninvasive method of evaluating cellular function is of importance both as endpoints for clinical trials and to our understanding of the biological mechanisms of cancer.

Is the future of personalized therapy in triple-negative breast cancer based on molecular subtype?

Significant research has been conducted to better understand the extensive, heterogeneous molecular features of triple-negative breast cancer (TNBC). We reviewed published TNBC molecular classifications to identify major groupings that have potential for clinical trial development. With the ultimate aim to streamline translational medicine, we linked these categories of TNBC according to their gene-expression signatures, biological function, and clinical outcome. To this end, we define five potential clinically actionable groupings of TNBC: 1) basal-like TNBC with DNA-repair deficiency or growth factor pathways; 2) mesenchymal-like TNBC with epithelial-to-mesenchymal transition and cancer stem cell features; 3) immune-associated TNBC; 4) luminal/apocrine TNBC with androgen-receptor overexpression; and 5) HER2-enriched TNBC. For each defined subtype, we highlight the major biological pathways and discuss potential targeted therapies in TNBC that might abrogate disease progression. However, many of these potential targets need clinical validation by clinical trials. We have yet to know how we can enrich the targets by molecular classifications.

Role of scintimammography in assessing the response of neoadjuvant chemotherapy in locally advanced breast cancer

Locally advanced breast cancer (LABC) is a common cancer in the developing countries. Neoadjuvant chemotherapy (NACT) is a very important step in the treatment of such tumors and hence that the disease can be down staged and made amenable for surgery. All the tumors do not respond to the therapy equally. Hence, it becomes very important to predict the response of chemotherapy in such cases. This study evaluated the role of scintimammography in assessing the response to NACT in 23 patients with LABC. Histologically proven 23 patients of LABC were recruited in this study. Prechemotherapy tumor size was measured clinically in all patients and technitium (Tc)-99m sestamibi test was performed before NACT for each patient. Early (10 min) and delayed (2 h) image of the breast were acquired in anterior and lateral views after Tc-99m sestamibi intravenous injections and wash out rate (WOR) was computed. After 3-4 cycles of chemotherapy, surgery in the form of modified radical mastectomy was performed in 20 out of 23 patients (3 patients lost to follow-up) with pathologic evaluation of the residual tumor size. The pretherapy Tc-99m sestamibi WOR ranged from 8.3% to 68% with mean ± SD of 34.5% ±16.5%. The prechemotherapy Tc-99m sestamibi study predicted chemoresistance (WOR >45%) in 6 out of 20 patients and no chemoresistance (WOR <45%) in 14 out of 20 patients. When the WOR cut-off was set at >45%, the predictivity of the test was indicated by sensitivity of 91.7%, specificity of 62.5%, positive predictive value of 78.6%, and negative predictive value of 82.3% with a likelihood ratio of 0.1. Tc-99m sestamibi WOR is a reliable test for predicting tumor response to NACT. WOR >45% is highly predictive of chemoresistance with likelihood ratio of 0.1 than WOR <45% being predictive of chemoresponsiveness.

Neoadjuvant therapy in the treatment of breast cancer

Neoadjuvant systemic therapy in breast cancer treatment was initially utilized for inoperable disease. However, several randomized prospective studies have demonstrated comparable survival with adjuvant chemotherapy in early-stage, operable breast cancer while also decreasing tumor size facilitating breast conservation without significant increases in local recurrence. Response to therapy can predict outcome, with improved survival associated with pathologic complete response (pCR). Triple negative and HER2-positive subtypes show increased pCR rates. A multidisciplinary approach is necessary with neoadjuvant treatment. This can improve rates of breast conservation, provide insights into tumor biology and predict patient outcomes.

Applications for breast magnetic resonance imaging

This article reviews the relevant data on breast magnetic resonance imaging (MRI) use in screening, the short-term surgical outcomes and long-term cancer outcomes associated with the use of MRI in breast cancer staging, the use of MRI in occult primary breast cancer, as well as MRI to assess eligibility for accelerated partial breast irradiation and to evaluate tumor response after neoadjuvant chemotherapy. MRI for screening is supported in specific high-risk populations, namely, women with BRCA1 or BRCA2 mutations, a family history suggesting a hereditary breast cancer syndrome, or a history of chest wall radiation.

Breast conservation therapy after neoadjuvant chemotherapy: optimization of a multimodality approach

Neoadjuvant chemotherapy (NAC) is routinely used in locally advanced breast cancer, but is increasingly used in early stage patients. Even patients with advanced disease can achieve excellent outcomes with breast conservation therapy (BCT) after NAC. The use of NAC followed by BCT is an example of how multimodality therapy can optimize outcomes while limiting morbidity and preserving cosmetic outcomes. Open communication between the multidisciplinary team is crucial to selecting appropriate candidates for this approach.

The role of mammographic calcification in the neoadjuvant therapy of breast cancer imaging evaluation

Introduction

Investigate the patterns of mammographically detected calcifications before and after neoadjuvant chemotherapy (NACT) to determine their value for efficacy evaluation and surgical decision making.

Methods

187 patients with malignant mammographic calcifications were followed to record the appearances and changes in the calcifications and to analyze their responses to NACT.

Results

Patients with calcifications had higher rates of hormonal receptor (HR) positive tumors (74.3% versus 64.6%) and HER2 positive tumors (51.3% versus 33.4%, p = 0.004) and a similar pathologic complete response (pCR) rate compared to patients without calcifications (35.4% versus 29.8%). After NACT, the range of calcification decreased in 40% of patients, increased in 7.5% and remained stable in 52.5%; the calcification density decreased in 15% of patients, increased in 7.5% and remained stable in 77.5%; none of these change patterns were related to tumor response rate. No significant correlation was observed between the calcification appearance (morphology, distribution, range, diameter or density) and tumor subtypes or pCR rates. Among patients with malignant calcifications, 54 showed calcifications alone, 40 occurred with an architectural distortion (AD) and 93 with a mass. Calcifications were observed inside the tumor in 44% of patients and outside in 56%, with similar pCR rates and patterns of change.

Conclusions

Calcification appearance did not clearly change after NACT, and calcification patterns were not related to pCR rate, suggesting that mammogram may not accurate to evaluate tumor response changes. Microcalcifications visible after NACT is essential for determining the extent of excision, patients with calcifications that occurred outside of the mass still had the opportunity for breast conservation.

Time to stop operating on breast cancer patients with pathological complete response?

Surgery is an obligatory component of treatment for early breast cancer. The last 20 years developments in systemic neoadjuvant therapy have progressively increased pathological complete response (pCR). Pathological complete response is associated with excellent prognosis especially for hormone receptor negative cancers. Therapeutic advances and recognition of the importance of pathological subtype in predicting pCR facilitate identification of subgroups with very high pCR rates. Treatment of HER2 positive hormone receptor negative cancers with combination chemotherapy and multiple targeted anti-HER2 agents results in consistently high pCR rates of 60-83%. Routine surgery in this setting where most patients have no potential to benefit is of questionable value and the option of omitting surgery in these patients should now be explored in a randomized trial. For HER2 positive disease not achieving pCR after neoadjuvant treatment the outcomes are poor. Trials are underway to determine if outcomes for these patients can be improved with alternative targeted therapy.

Accuracy of clinical examination, digital mammogram, ultrasound, and MRI in determining postneoadjuvant pathologic tumor response in operable breast cancer patients

BACKGROUND

To determine the accuracy, positive predictive value (PPV), and negative predictive value (NPV) of clinical examination and breast imaging techniques in determining pathologic complete response in patients with locally advanced breast cancer after neoadjuvant therapy.

METHODS

A retrospective review was performed of data collected from patients treated with either neoadjuvant hormonal or chemotherapy between January 2005 and September 2010. Patients were evaluated by one of three surgical breast oncologists before neoadjuvant therapy and within 1 month before surgery by clinical breast examination (CBE), digital mammogram, breast ultrasound, and/or magnetic resonance imaging (MRI). The accuracy, NPV, and PPV of each modality was calculated on the basis of the final pathologic report. Available data from the literature was synthesized.

RESULTS

Sixty-two tumors in 61 patients with a mean age of 56 (range 34-87) years were evaluated. Overall accuracy ranged from 54% (CBE) to 80% (breast ultrasound). All modalities had a PPV greater than 75% for identifying the presence of residual disease. The PPV of each modality was generally higher in the younger patients. The NPV of all methods was less than 50%. The accuracy and NPV were compromised even further in younger patients. The combination of our own data with data available from the literature revealed MRI to be superior with regard to accuracy and PPV, but the NPV of MRIs remained poor at 65%.

CONCLUSIONS

All measured tests are good at predicting the presence of disease on final pathology, but none are able to reliably predict a pathologic complete response.

Magnetic resonance imaging of the breast for cancer diagnosis and staging

Gadolinium-enhanced breast magnetic resonance imaging (MRI) is optimally suited for the diagnosis and assessment of breast cancer. The complete breast MRI examination, which includes select nonenhanced sequences, yields abundant information about the nature and stage of disease. In this article, we will explore cancer diagnosis by examining the main imaging features of breast malignancy as well as the assessment of surrounding structures. We will then discuss current ideas in the use of breast MRI in breast cancer, including high-risk screening, evaluation of extent of disease, role in surgical planning, and the use of MRI in the patient receiving neoadjuvant chemotherapy. Breast MRI plays an important role in the assessment of patients with breast malignancy-a role that is yet to be fully defined and used. By understanding the strengths and weakness of this imaging method in cancer evaluation, we hope to highlight the appropriate uses of the technique.