Pathobiology of preoperative chemotherapy: findings from the National Surgical Adjuvant Breast and Bowel (NSABP) protocol B-18

The prevalence and clinical significance of residual occult breast cancer after neoadjuvant chemotherapy: reassessing surgical pathology in cases initially described as pathological complete response

AIMS

Evaluation of pathological complete response (pCR) [no residual invasive carcinoma in the breast (RIC) or lymph node metastases (LNM) in surgical specimens following therapy] is typically based on evaluation of one level of haematoxylin and eosin (H&E) section. Not achieving pCR is associated with worse outcomes, and additional therapy may ensue. This study of patients with triple-negative (TNBC) or human epidermal growth factor receptor 2 (HER2)-positive (HER2+) breast cancer who underwent neoadjuvant therapy aims to assess whether occult residual disease (ORD) can be identified in deeper sections of tumour beds and lymph nodes in cases originally reported as pCR and whether ORD is associated with worse outcomes.

METHODS AND RESULTS

In 84 cases of pCR (2009-17) at our institution, deeper-level recuts were assessed for ORD. Oncological and survival outcomes were compared. ORD was identified in seven of 40 TNBC (17.5%; five RIC; one LMN; one RIC and LMN) and four of 44 HER2+ (9.1%; three RIC; one LMN) cases (all residual cancer burden I). Median follow-up was 46.7 months for TNBC (one local recurrence, four distant metastases and two deaths) and 86.8 months for HER2+ (no local recurrence, three distant metastases and two deaths). All recurrence and death events occurred in patients with pCR without ORD, with no recurrence events in patients with ORD.

CONCLUSIONS

In patients with TNBC and HER2+ breast cancer with pCR by standard pathological assessment, occult residual disease is not uncommon. Occult disease was not associated with worse oncological or survival outcomes, suggesting standard pathological assessment is sufficient to identify clinically meaningful disease.

Real Index of Refraction of Normal and Cancerous Axillary Lymph Nodes in Breast Cancer Patients: Results from an Experimental Study

Background: Breast malignancy is the most common cancer type and the second leading cause of cancer-related death for women all ages. Axillary surgery provides prognostic and predictive information, but carries significant morbidity. Imaging techniques are a promising field, providing the characterization of biological tissues using the interaction between the light and a medium, and may offer an accurate cancerous diagnosis without the need for formal histopathological examination. Methods: In this study, using a prism couple refractometer, we sought to determine tissues' reflection profiles in freshly excised human lymph nodes from female patients with breast cancer, in whom axillary lymph node dissection was performed. Results: Thirty-four patients were included, contributing a total number of 90 lymph nodes and, according to our results, the median refractive indices were significantly higher in cancerous lymph nodes compared to normal lymph nodes in 450 nm, 964 nm, and 1551 nm wavelengths (p < 0.05). Conclusions: Results from this small experimental study imply that the use of a prism couple refractometer may aid in the discrimination between benign and malignant axillary lymph nodes in female patients with breast cancer.

Accessible model predicts response in hormone receptor positive HER2 negative breast cancer receiving neoadjuvant chemotherapy

Hormone receptor-positive/HER2-negative breast cancer (BC) is the most common subtype of BC and typically occurs as an early, operable disease. In patients receiving neoadjuvant chemotherapy (NACT), pathological complete response (pCR) is rare and multiple efforts have been made to predict disease recurrence. We developed a framework to predict pCR using clinicopathological characteristics widely available at diagnosis. The machine learning (ML) models were trained to predict pCR (n = 463), evaluated in an internal validation cohort (n = 109) and validated in an external validation cohort (n = 151). The best model was an Elastic Net, which achieved an area under the curve (AUC) of respectively 0.86 and 0.81. Our results highlight how simpler models using few input variables can be as valuable as more complex ML architectures. Our model is freely available and can be used to enhance the stratification of BC patients receiving NACT, providing a framework for the development of risk-adapted clinical trials.

Cyberneo trial investigating the efficacy of stereotactic radiotherapy combined to neoadjuvant chemotherapy for locally advanced breast cancer: 14-years follow-up results

PURPOSE

The purpose of the phase I trial named "Cyberneo" was to define the efficacy of the stereotactic radiotherapy using CyberKnife® for locally advanced (stage III) breast tumours combined to a neoadjuvant chemotherapy for patients for whom a conservative surgery could not be considered at the onset. Neoadjuvant chemotherapy consisted of six cycles: three cycles of docetaxel and three cycles of the combination of 5-fluorouracil, epirubicin and cyclophosphamide. Stereotactic radiotherapy using CyberKnife® was performed during the second cycle of chemotherapy. Breast surgery was performed 6 to 8 weeks later and conventional breast irradiation without boost, afterwards. The main objective was to define the maximum tolerated dose of hypofractionated radiotherapy concurrent with neoadjuvant chemotherapy. We present an updated survival data for patients included in this trial and we evaluate the late toxicity of this combination.

PATIENTS AND METHODS

We updated the survival data of 25 patients treated for a stage III breast cancer between 2007 and 2009 at the Antoine-Lacassagne centre in Nice and included in the Cyberneo trial by recording late toxicity events and aesthetic results.

RESULTS

With a median follow-up of 12 years (95 % confidence interval [CI]: 10-14 years), 19 patients were in remission (76 %), one patient had a controlled axillary lymph node relapse (4 %) and five patients (20 %) died due to metastatic progression within a median of 5 years after treatment (range: 1-9 years). Nine patients had a complete histological response (36 %). The highest percentage of complete histological response was in the group of patients treated in the fourth stage (28.5Gy in four fractions). Overall survival rate at 14 years was 71 % (95 % CI: [53-94 %]). Two patients developed chronic radiation toxicity during follow-up with a fibrosis (8 %) of which one was in the fourth stage and one in the fifth stage (31.5Gy). Three patients (12 %) had a change of prosthesis after treatment, which for one patient was 24 months after the end of support.

CONCLUSION

The updated results of the Cyberneo trial with 14 years of follow-up confirm the satisfactory results in terms of local control with an excellent long-term safety profile.

Diagnostic accuracy of sentinel lymph node biopsy and wire localized clipped node biopsy after neoadjuvant chemotherapy in node-positive breast cancer

PURPOSE

The optimal method for axillary staging in patients with initially node-positive breast cancer after NACT remains unclear.

METHODS

We conducted a prospective, single-center trial to investigate the diagnostic performance of sentinel lymph node biopsy (SLNB) combined with wire localized lymph node biopsy (WLNB) of the clip-marked node as an axillary staging technique in patients with node-positive breast cancer after neoadjuvant chemotherapy (NACT).

RESULTS

A total of 233 patients were enrolled, 208 of whom were included in the analysis. The IR of SLNB and WLNB alone were 63.0% and 70.7%, respectively. The identification rate (IR) of targeted axillary dissection (TAD) was 87.5%. The FNR of and NPV were 6.9% (95% confidence interval [CI]:2.0-11.8%) and 92.0% (95% CI 86.3-97.7%), respectively, for the TAD procedure, 17.1% (95% CI 8.2-25.6%) and 83.3% (95% CI:74.7-91.9%) for SLNB alone, and 6.7% (95% CI:1.5-12.0%) and 90.6% (95% CI:83.5-97.7%) for WLNB alone.

CONCLUSIONS

The diagnostic performance of TAD using wire localization was similar to that of the procedure performed using radioactive seed localization. (Clinical Trial Registration: NCT03715686).

The prognostic value of histological grade determined after neoadjuvant chemotherapy of breast cancer

Histological grade is a validated prognostic factor of breast cancer but may show alterations following neoadjuvant chemotherapy (NACT). Its reporting after NACT is recommended by several guidelines, but evidence of its retained prognostic impact is scarce. Patients treated with NACT followed by surgery and having sufficient residual tumour for the determination of grade were analysed for the survival effects of posttreatment grade (yG). Kaplan-Meier analyses and the log-rank test were applied, followed by the univariable and multivariable Cox proportional hazards models. The cohort comprised 355 patients with known yG, and 320 of them had also a pretreatment grade available. Pretreatment grade changed in 99/320 (31 %) cases following NACT, and downgrading was more common (n=78/320, 24 %) than upgrading (21/320, 7 %). Among 355 breast cancer patients, those with yG3 (poorly differentiated) tumours (n=155) had worse 5-year relapse-free and overall survival estimates than those with yG2 (n=169) or yG1 (n=31) tumours. This was also substantiated by univariable analysis; however, yG lost its significance in the multivariable model. Post-NACT histological grade has a prognostic impact, but does not seem to be an independent prognosticator in the post-NACT setting; however, these results lend support for its reporting by pathologists after primary systemic treatment.

Three-dimensional analysis of mitochondria in a patient-derived xenograft model of triple negative breast cancer reveals mitochondrial network remodeling following chemotherapy treatments

Mitochondria are hubs of metabolism and signaling and play an important role in tumorigenesis, therapeutic resistance, and metastasis in many cancer types. Various laboratory models of cancer demonstrate the extraordinary dynamics of mitochondrial structure, but little is known about the role of mitochondrial structure in resistance to anticancer therapy. We previously demonstrated the importance of mitochondrial structure and oxidative phosphorylation in the survival of chemotherapy-refractory triple negative breast cancer (TNBC) cells. As TNBC is a highly aggressive breast cancer subtype with few targeted therapy options, conventional chemotherapies remain the backbone of early TNBC treatment. Unfortunately, approximately 45% of TNBC patients retain substantial residual tumor burden following chemotherapy, associated with abysmal prognoses. Using an orthotopic patient-derived xenograft mouse model of human TNBC, we compared mitochondrial structures between treatment-naïve tumors and residual tumors after conventional chemotherapeutics were administered singly or in combination. We reconstructed 1,750 mitochondria in three dimensions from serial block-face scanning electron micrographs, providing unprecedented insights into the complexity and intra-tumoral heterogeneity of mitochondria in TNBC. Following exposure to carboplatin or docetaxel given individually, residual tumor mitochondria exhibited significant increases in mitochondrial complexity index, area, volume, perimeter, width, and length relative to treatment-naïve tumor mitochondria. In contrast, residual tumors exposed to those chemotherapies given in combination exhibited diminished mitochondrial structure changes. Further, we document extensive intra-tumoral heterogeneity of mitochondrial structure, especially prior to chemotherapeutic exposure. These results highlight the potential for structure-based monitoring of chemotherapeutic responses and reveal potential molecular mechanisms that underlie chemotherapeutic resistance in TNBC.

Is Ki-67 Really Useful as a Predictor for Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer?

Neoadjuvant chemotherapy (NACT) is routinely offered to operable locally advanced breast cancer (LABC) patients desirous of breast conservation surgery and inoperable LABC patients. Pathological complete response (pCR) following chemotherapy is recognized as a surrogate for survival outcomes in high grade tumour subtypes. Many biological and tumor characters have been shown to predict pCR. The current study was performed with the aim of investigating the ability of Ki-67 in predicting pCR with NACT in breast cancer patients. A total of 105 patients with locally advanced breast cancer who completed NACT followed by surgery were included in this study from January 2020 till December 2022. Patients with advanced metastatic breast carcinoma, who did not give consent for NACT, who did not complete NACT and who did not undergo surgery were excluded. All patients were assessed for Ki-67 score on core-needle biopsy samples and response rate was assessed clinically and by histopathological examination of resected specimen. Quantitative variables were compared using unpaired t-test or Mann-Whitney 'U' test and for categorical variables Chi-square or Fisher's exact test were used. Receiver operating characteristic (ROC) curve analysis was performed to assess the predictive potential of Ki-67 expression levels in predicting pCR. To identify the predictive factors associated with pCR, univariate analysis was performed. The P value < 0.05 was considered as statistically significant. Mean age was 51.57 ± 10.8 years. 51 patients achieved clinical complete response (cCR) and 33 achieved pCR after NACT. Mean Ki-67 index in overall study population, in pCR group and no pCR group was 46.44 ± 22.92%, 51.60 ± 22.3% and 44.06 ± 22.7%, respectively. On univariate analysis, ER negativity, PR negativity and Her 2neu positivity were found predictive of pCR. On subgroup analysis, TNBC and Her 2neu positive sub groups were associated with higher cCR and pCR rate. We found no significant association between Ki-67 and pCR. This result may be confounded by the fact that a significant duration of the study was in the COVID-19 pandemic. Validation of this data is required in a large prospective study.

Nodal positivity in patients with clinically and radiologically node-negative breast cancer treated with neoadjuvant chemotherapy: multicentre collaborative study

BACKGROUND

The necessity of performing a sentinel lymph node biopsy in patients with clinically and radiologically node-negative breast cancer after neoadjuvant chemotherapy has been questioned. The aim of this study was to determine the rate of nodal positivity in these patients and to identify clinicopathological features associated with lymph node metastasis after neoadjuvant chemotherapy (ypN+).

METHODS

A retrospective multicentre study was performed. Patients with cT1-3 cN0 breast cancer who underwent sentinel lymph node biopsy after neoadjuvant chemotherapy between 2016 and 2021 were included. Negative nodal status was defined as the absence of palpable lymph nodes, and the absence of suspicious nodes on axillary ultrasonography, or the absence of tumour cells on axillary nodal fine needle aspiration or core biopsy.

RESULTS

A total of 371 patients were analysed. Overall, 47 patients (12.7%) had a positive sentinel lymph node biopsy. Nodal positivity was identified in 22 patients (29.0%) with hormone receptor+/human epidermal growth factor receptor 2- tumours, 12 patients (13.8%) with hormone receptor+/human epidermal growth factor receptor 2+ tumours, 3 patients (5.6%) with hormone receptor-/human epidermal growth factor receptor 2+ tumours, and 10 patients (6.5%) with triple-negative breast cancer. Multivariable logistic regression analysis showed that multicentric disease was associated with a higher likelihood of ypN+ (OR 2.66, 95% c.i. 1.18 to 6.01; P = 0.018), whilst a radiological complete response in the breast was associated with a reduced likelihood of ypN+ (OR 0.10, 95% c.i. 0.02 to 0.42; P = 0.002), regardless of molecular subtype. Only 3% of patients who had a radiological complete response in the breast were ypN+. The majority of patients (85%) with a positive sentinel node proceeded to axillary lymph node dissection and 93% had N1 disease.

CONCLUSION

The rate of sentinel lymph node positivity in patients who achieve a radiological complete response in the breast is exceptionally low for all molecular subtypes.

Transaxillary Single-Port Endoscopic Nipple-Sparing Mastectomy with Immediate Implant-based Breast Reconstruction in Breast Cancer Patients Receiving Neoadjuvant Chemotherapy or Not: A Comparative Study with Analysis of Surgical Complications and Patient-Reported Outcomes

BACKGROUND

In most cases, transaxillary single-port endoscopic nipple-sparing mastectomy with immediate implant-based breast reconstruction (E-NSM-IIBR) is conducted in patients with early-stage breast cancer, ensuring surgical safety while achieving improved breast aesthetics. However, whether E-NSM-IIBR is appropriate in patients undergoing neoadjuvant chemotherapy (NAC) is still unclear. The aim of this study was to report the surgical safety and patient-reported outcomes (PROs) of breast cancer patients who underwent E-NSM-IIBR with NAC in comparison to those who did not receive NAC.

METHODS

A retrospective cohort study was conducted on patients who underwent E-NSM-IIBR with or without NAC at a single center between January 2021 and July 2022. Patient demographics, postoperative complications, and PROs evaluated using the BREAST-Q version 2.0 questionnaire were compared between the two groups. Factors associated with PROs at 9 months after surgery were assessed with linear regression analysis.

RESULTS

A total of 92 patients who underwent E-NSM-IIBR were included in the study, with 27 patients receiving NAC and 65 patients not receiving NAC. There was no significant difference in the incidence of postoperative complications between the two groups. The BREAST-Q version 2.0 questionnaire was completed by 24 out of 27 patients (88.9%) in the NAC group and 59 out of 65 patients (90.8%) in the non-NAC group at 9 months after surgery. The patient-reported outcomes in various domains of the BREAST-Q did not show a significant difference between the two cohorts. The results of the multiple linear regression analysis indicated that in the both groups age (β = - 0.985, 95% CI - 1.598 to - 0.371, p = 0.003 in the NAC group; β = - 0.510, - 1.011 to - 0.009, p = 0.046 in the non-NAC group) and rippling (β = - 21.862, - 36.768 to - 6.955, p = 0.006 in the NAC group; β = - 7.787, - 15.151 to - 0.423, p = 0.039 in the non-NAC group) significantly impacted the patients' satisfaction with breasts, and PMRT was negatively associated with patients' physical well-being of chest (β = - 13.813, - 26.962 to - 0.664, p = 0.040 in the NAC group; β = - 18.574, - 30.661 to - 6.487, p = 0.003 in the non-NAC group). Our findings revealed that patients with larger implant volumes had higher scores in psychosocial well-being (β = 0.082, 0.001 to 0.162, p = 0.047), whereas implant displacement (β = - 14.937, - 28.175 to - 1.700, p=0.028) had a negative impact on patients' psychological well-being in the non-NAC group. However, our results did not demonstrate any significant influencing factors on patients' psychosocial well-being within the NAC group.

CONCLUSION

Our preliminary experiences confirm that E-NSM-IIBR is a safe option for selected patients even after NAC, with favorable patient-reported outcomes comparable with those in the primary surgery setting. The postoperative long-term outcomes of patients who undergo radiation therapy after NAC merit further investigation in the future.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Stroma-Mediated Breast Cancer Cell Proliferation Indirectly Drives Chemoresistance by Accelerating Tumor Recovery between Chemotherapy Cycles

The ability of tumors to survive therapy reflects both cell-intrinsic and microenvironmental mechanisms. Across many cancers, including triple-negative breast cancer (TNBC), a high stroma/tumor ratio correlates with poor survival. In many contexts, this correlation can be explained by the direct reduction of therapy sensitivity induced by stroma-produced paracrine factors. We sought to explore whether this direct effect contributes to the link between stroma and poor responses to chemotherapies. In vitro studies with panels of TNBC cell line models and stromal isolates failed to detect a direct modulation of chemoresistance. At the same time, consistent with prior studies, fibroblast-produced secreted factors stimulated treatment-independent enhancement of tumor cell proliferation. Spatial analyses indicated that proximity to stroma is often associated with enhanced tumor cell proliferation in vivo. These observations suggested an indirect link between stroma and chemoresistance, where stroma-augmented proliferation potentiates the recovery of residual tumors between chemotherapy cycles. To evaluate this hypothesis, a spatial agent-based model of stroma impact on proliferation/death dynamics was developed that was quantitatively parameterized using inferences from histologic analyses and experimental studies. The model demonstrated that the observed enhancement of tumor cell proliferation within stroma-proximal niches could enable tumors to avoid elimination over multiple chemotherapy cycles. Therefore, this study supports the existence of an indirect mechanism of environment-mediated chemoresistance that might contribute to the negative correlation between stromal content and poor therapy outcomes.

SIGNIFICANCE

Integration of experimental research with mathematical modeling reveals an indirect microenvironmental chemoresistance mechanism by which stromal cells stimulate breast cancer cell proliferation and highlights the importance of consideration of proliferation/death dynamics. See related commentary by Wall and Echeverria, p. 3667.

Naples score: a novel prognostic biomarker for breast cancer patients undergoing neoadjuvant chemotherapy

BACKGROUND AND PURPOSE

The Naples Score (NPS) is a novel prognostic indicator that has been used in various cancers, but its potential in breast malignant tumor patients receiving neoadjuvant chemotherapy (NAC) has not been discovered. This study aimed to investigate the relationship between NPS and overall survival (OS) and disease-free survival (DFS) in breast cancer patients.

METHODS

A total of 217 breast cancer patients undergoing NAC were incorporated into this retrospectively research. K-M survival curves and log-rank tests are used to determine OS and DFS. Cox regression model was used to evaluate the relationship between NPS and OS and DFS. Nomogram was developed based on the results of multivariate Cox regression analysis. Prognostic models were internally validated using bootstrapping and the consistency index (C-index).

RESULTS

Age group was correlated with NPS (p < 0.05). Low and moderate Naples risk patients had higher 5-year OS and DFS rates than high risk Naples patients (93.8% vs. 75.4% vs. 60.0%; X2 = 9.2, P = 0.01; 82.4% vs 64.5% vs 43.7%; X2 = 7.4, P = 0.024; respectively). The nomogram based on demonstrated good performance in predicting OS and DFS (AUC = 0.728, 0.630; respectively).

CONCLUSIONS

In breast cancer patients who have undergone NAC, NPS is a novel prognostic indicator. NPS combined with clinicopathological features showed good predictive ability, and its performance was better than that of traditional pathological TNM staging.

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.

Response in axillary lymph nodes to neoadjuvant chemotherapy for breast cancers: correlation with breast response, pathologic features, and accuracy of radioactive seed localization

OBJECTIVES

This study examined the accuracy of radioactive seed localization (RSL) of lymph nodes (LNs) following neoadjuvant chemotherapy (NAC) for invasive breast carcinoma, recorded pathologic features of LNs following NAC, evaluated concordance of response between breast and LNs, and identified clinicopathologic factors associated with higher risk of residual lymph node involvement.

METHODS

Clinical records, imaging, and pathology reports and slides were retrospectively reviewed for 174 breast cancer patients who received NAC. Chi-square and Fisher's exact tests were used to compare differences in risk of residual lymph node disease.

RESULTS

Retrieval of biopsied pre-therapy positive LN was confirmed in 86/93 (88%) cases overall, and in 75/77 (97%) of cases utilizing RSL. Biopsy clip site was the best pathologic feature to confirm retrieval of a biopsied lymph node. Pre-therapy clinical N stage > 0, positive pre-therapy lymph node biopsy, estrogen and progesterone receptor positivity, Ki67 < 50%, HR + /HER2- tumors, and residual breast disease had higher likelihood of residual lymph node disease after NAC (p < 0.001).

CONCLUSIONS

RSL-guided LN excision improves retrieval of previously biopsied LNs following NAC. The pathologist can use histologic features to confirm retrieval of targeted LNs, and tumor characteristics can be used to predict a higher risk of residual LN involvement.

Effects of tumor-infiltrating lymphocytes on nonresponse rate of neoadjuvant chemotherapy in patients with invasive breast cancer

High level of tumor-infiltrating lymphocytes (TILs) can predict the rate of total pathological complete remission (tpCR) of breast cancer patients who receive neoadjuvant chemotherapy (NACT). This study focused on evaluating the data of patients whose primary tumor and/or lymph node metastasis show nonresponse (NR) to NACT, trying to provide a basis for the clinical decision which patients will develop NACT resistance. The study included breast cancers from 991 patients who received NACT. ROC curve analysis confirmed that TILs showed significant predictive value for NR of hormone receptor (HR)+HER2- and triple-negative breast cancer (TNBC). Among HR+HER2- breast cancer, TILs ≥ 10% was an independent predictor for low NR rate. Furthermore, positive correlation of TILs with Ki67 index and Miller-Payne grade, and negative correlation with ER and PR H-scores were only identified in this subgroup. In TNBC, TILs ≥ 17.5% was an independent predictor for low NR rate. The predictive value of low TILs on NR may facilitate to screen patients with HR+HER2- or TNBC who may not benefit from NACT. HR+HER2- breast cancer with low levels of TILs should be carefully treated with neoadjuvant chemotherapy, and other alternatives such as neoadjuvant endocrine therapy can be considered.

Effects of enhancer of zeste homolog 2 and mucin 1 expressions on treatment response in breast cancer

OBJECTIVE

Breast cancer is the most common malignancy in women. In the treatment of these patients, pathological complete response is defined as the absence of invasive cancer in breast or lymph node tissue after the completion of neoadjuvant chemotherapy. In this study, we aimed to investigate the relationship of enhancer of zeste homolog 2 and mucin 1 expressions with pathological complete response in patients with breast cancer receiving neoadjuvant chemotherapy.

METHODS

A total of 151 patients were included in the study. Enhancer of zeste homolog 2 and mucin 1 expressions were evaluated in the biopsy materials pre-neoadjuvant chemotherapy and post-neoadjuvant chemotherapy surgical material, and their relationship with pathological complete response was investigated.

RESULTS

The pathological complete response rates were significantly higher among the hormone receptor-negative patients, those with a high Ki-67 score, and patients with HER2-positive. Higher pathological complete response rates were obtained from patients with enhancer of zeste homolog 2 expression positivity pre-neoadjuvant chemotherapy. In addition, after neoadjuvant chemotherapy, enhancer of zeste homolog 2 expression was found to be completely negative in materials with pathological complete response; that is, in breast tissues considered to be tumor-free. While there was no significant relationship between mucin 1 expression and pathological complete response pre-neoadjuvant chemotherapy, mucin 1 expression was determined to significantly differ between the tissues with and without pathological complete response among the surgical materials examined.

CONCLUSION

In our study investigating the relationship between enhancer of zeste homolog 2 and mucin 1 expression and pathological complete response in patients who received neoadjuvant chemotherapy, we found that enhancer of zeste homolog 2 expression could be used as a predictive marker for pathological complete response. However, mucin 1 expression was not associated with pathological complete response.

Lessons from other fields of medicine, Part 1: Breast cancer

Through the understanding of multiple etiologies, pathologies, and disease progression trajectories, breast cancer shifted historically from a singular malignancy of the breast to a complex of molecular/biological entities, translating into individualized disease-modifying treatments. As a result, this led to various de-escalations of treatment compared with the gold standard in the era preceding systems biology: radical mastectomy. Targeted therapies have minimized morbidity from the treatments and mortality from the disease. Biomarkers further individualized tumor genetics and molecular biology to optimize treatments targeting specific cancer cells. Landmark discoveries in breast cancer management have evolved through histology, hormone receptors, human epidermal growth factor, single-gene prognostic markers, and multigene prognostic markers. Relevant to the reliance on histopathology in neurodegenerative disorders, histopathology evaluation in breast cancer can serve as a marker of overall prognosis rather than predict response to therapies. This chapter reviews the successes and failures of breast cancer research through history, with focus on the transition from a universal approach for all patients to divergent biomarker development and individualized targeted therapies, discussing future areas of growth in the field that may apply to neurodegenerative disorders.

Pathologic Complete Response and Oncologic Outcomes in Locally Advanced Breast Cancers Treated With Neoadjuvant Radiation Therapy: An Australian Perspective

PURPOSE

To assess the degree of pathologic complete response (pCR), postoperative surgical complication rates, and oncological outcomes in women with locally advanced breast cancer or high-risk breast cancers treated with neoadjuvant radiation therapy (NART).

METHODS AND MATERIALS

This retrospective, multi-institutional review involved 138 clinically staged patients with 140 breast cancers treated with NART between January 2014 and February 2021. Treatments involved sequential neoadjuvant chemotherapy and NART, followed by mastectomy with or without axillary surgery and immediate autologous breast reconstruction. Descriptive statistics were used to assess patient and disease features, treatment regimens, pathologic response, and factors affecting postoperative complications. Kaplan-Meier curves were performed to assess locoregional recurrence-free, distant metastasis-free, and overall survival outcomes.

RESULTS

Median age was 47 years (interquartile range, 42-52). The median follow-up was 35.2 months (interquartile range, 17.1-46.5). pCR was achieved in 36.4% (as defined by Chevallier classification) or 42.1% (as defined by Miller-Payne scores) of patients. Greater pCR rates were achieved for HER2+ (73.8%-85.7%) and triple-negative phenotypes (47.6%-57.1%). There were 21 grade 3 surgical complications including 10 grade 3B breast events and 8 grade 3B donor-site events, where surgical reintervention was required. At 3-years' follow-up, the locoregional recurrence-free survival was 98.1%, distant metastasis-free survival was 83.6%, and overall survival was 95.3%%.

CONCLUSIONS

NART is feasible to facilitate a single-stage mastectomy and immediate autologous breast reconstruction. This study demonstrated comparable rates of postoperative complication to standard of care, and high rates of pCR, which translates to high rates of locoregional control, distant metastasis-free survival, and overall survival.

Efficacy evaluation of neoadjuvant chemotherapy in patients with HER2-low expression breast cancer: A real-world retrospective study

BACKGROUND

To characterize the clinicopathological features and evaluate the neoadjuvant chemotherapy (NACT) efficacy of patients with human epidermal growth factor receptor 2 (HER2)-low breast cancer.

METHODS

A total of 905 breast cancer patients who received 4 cycles of thrice-weekly standard NACT in the First Affiliated Hospital of Chongqing Medical University were retrospectively enrolled, including 685 cases with HER2-low expression and 220 cases with HER2-negative expression. Clinicopathological features were compared between patients with HER2-negative and HER2-low expression. Univariate and multivariate logistic regression analyses were used to find the independent factors of achieving a pathological complete response (pCR) after NACT.

RESULTS

There were significant differences in stage_N (P = 0.014), histological grade (P = 0.001), estrogen receptor (ER) status (P < 0.001), progesterone receptor (PgR) status (P < 0.001), NACT regimens (P = 0.032) and NACT efficacy (P = 0.037) between patients with HER2-negative and HER2-low expression breast cancer. In subgroup analysis, histological grade (P = 0.032), ER (P = 0.002), Ki-67 (P < 0.001) and HER2 status (P = 0.025) were independent predictors of achieving a pCR in ER-positive breast cancer. And the nomogram for pCR in ER-positive breast cancer showed great discriminatory ability with an AUC of 0.795. The calibration curve also showed that the predictive ability of the nomogram was a good fit to actual observations. Then, in the analysis of ER-negative breast cancer, only stage_N (P = 0.001) and Ki-67 (P = 0.018) were independent influencing factors of achieving a pCR in ER-negative breast cancer.

CONCLUSION

HER2-low breast cancer was a different disease from HER2-negative breast cancer in clinicopathological features. Moreover, the NACT efficacy of HER2-low breast cancer patients was poorer.

Prognostic value of a modified systemic inflammation score in breast cancer patients who underwent neoadjuvant chemotherapy

BACKGROUND AND PURPOSE

The modified systemic inflammation score (mSIS) system, which is constructed based on the neutrophil to lymphocyte ratio (NLR) and albumin (Alb), has not been applied to evaluate the prognosis of malignant breast cancer patients who underwent neoadjuvant chemotherapy (NAC). The present study aimed to explore the relationship between the mSIS and overall survival (OS), disease-free survival (DFS) and pathological complete response (pCR).

METHODS

A total of 305 malignant breast tumor patients who underwent NAC were incorporated into this retrospective analysis. We determined OS and DFS using K-M survival curves and the log-rank test. The relationship between the mSIS and OS and DFS was evaluated by a Cox regression model. A nomogram was constructed based on Cox regression analysis.

RESULTS

Patients in the mSIS low-risk group had better 5- and 8-year OS rates than those in the mSIS high-risk group (59.8% vs. 77.0%; 50.1% vs. 67.7%; X² = 8.5, P = 0.0035, respectively). Patients in the mSIS (1 + 2 score) + pCR subgroup had the highest 5- and 8-year OS and disease-free survival (DFS) rates (OS: 55.0% vs. 75.7% vs. 84.8, 42.8% vs. 65.7% vs. 79.8%, X² = 16.6, P = 0.00025; DFS: 38.8% vs. 54.7% vs. 76.3%, 33.3% vs. 42.3 vs. 72.1%, X2 = 12.4, P = 0.002, respectively). Based on the mSIS, clinical T stage and pCR results, the nomogram had better predictive ability than the clinical TNM stage, NLR and Alb.

CONCLUSIONS

mSIS is a promising prognostic tool for malignant breast tumor patients who underwent NAC, and the combination of mSIS and pCR is helpful in enhancing the ability to predict a pCR.

Machine learning models based on immunological genes to predict the response to neoadjuvant therapy in breast cancer patients

Breast cancer (BC) is the most common malignancy worldwide and neoadjuvant therapy (NAT) plays an important role in the treatment of patients with early BC. However, only a subset of BC patients can achieve pathological complete response (pCR) and benefit from NAT. It is therefore necessary to predict the responses to NAT. Although many models to predict the response to NAT based on gene expression determined by the microarray platform have been proposed, their applications in clinical practice are limited due to the data normalization methods during model building and the disadvantages of the microarray platform compared with the RNA-seq platform. In this study, we first reconfirmed the correlation between immune profiles and pCR in an RNA-seq dataset. Then, we employed multiple machine learning algorithms and a model stacking strategy to build an immunological gene based model (Ipredictor model) and an immunological gene and receptor status based model ICpredictor model) in the RNA-seq dataset. The areas under the receiver operator characteristic curves for the Ipredictor model and ICpredictor models were 0.745 and 0.769 in an independent external test set based on the RNA-seq platform, and were 0.716 and 0.752 in another independent external test set based on the microarray platform. Furthermore, we found that the predictive score of the Ipredictor model was correlated with immune microenvironment and genomic aberration markers. These results demonstrated that the models can accurately predict the response to NAT for BC patients and will contribute to individualized therapy.

Lymph node staging after primary systemic therapy in women with breast cancer and lymph node involvement at diagnosis

OBJECTIVE

The main objective of this study is to analyze the efficacy of combined axillary marking (lymph node clipping and sentinel lymph node biopsy (SLNB)) for axillary staging in patients with primary systemic treatment (PST) and pathologically confirmed node-positive breast cancer at diagnosis. The secondary objective is to determine the impact of lymph node marking in the suppression of axillary lymph node dissection (ALND) in the study group.

METHODS

We conducted a prospective study in which lymph node staging was performed using wire localization of positive lymph nodes and a SLNB with dual tracer. All patients who presented no metastatic involvement of the sentinel lymph node (SLN) or clip/wire-marked lymph node were spared an ALND. The multidisciplinary committee agreed on axillary treatment for patients with lymph node involvement.

RESULTS

Eighty one patients met the inclusion criteria. We identified and extirpated the clip/ wire-marked node in 80 of 81 patients (98.8%), with SLNB performed successfully in 88,9% of patients. The SLN and wire-marked node matched in 78.9% of patients; 76.2% of patients did not undergo ALND.

CONCLUSIONS

The combined axillary marking (clip and SLNB) in patients with metastatic lymph node at diagnosis and PST offers a high identification rate (98.8%) and a high correlation between the wire-marked lymph node and the SLN (78.9%). This procedure has enabled the suppression of ALND in 76.2% of patients.

Pathologic Examination of Pancreatic Specimens Resected for Treated Pancreatic Ductal Adenocarcinoma: Recommendations From the Pancreatobiliary Pathology Society

Currently, there are no internationally accepted consensus guidelines for pathologic evaluation of posttherapy pancreatectomy specimens. The Neoadjuvant Therapy Working Group of Pancreatobiliary Pathology Society was formed in 2018 to review grossing protocols, literature, and major issues and to develop recommendations for pathologic evaluation of posttherapy pancreatectomy specimens. The working group generated the following recommendations: (1) Systematic and standardized grossing and sampling protocols should be adopted for pancreatectomy specimens for treated pancreatic ductal adenocarcinoma (PDAC). (2) Consecutive mapping sections along the largest gross tumor dimension are recommended to validate tumor size by histology as required by the College of American Pathologists (CAP) cancer protocol. (3) Tumor size of treated PDACs should be measured microscopically as the largest dimension of tumor outer limits that is bound by viable tumor cells, including intervening stroma. (4) The MD Anderson grading system for tumor response has a better correlation with prognosis and better interobserver concordance among pathologists than does the CAP system. (5) A case should not be classified as a complete response unless the entire pancreas, peripancreatic tissues, ampulla of Vater, common bile duct, and duodenum adjacent to the pancreas are submitted for microscopic examination. (6) Future studies on tumor response of lymph node metastases, molecular and/or immunohistochemical markers, as well as application of artificial intelligence in grading tumor response of treated PDAC are needed. In summary, systematic, standardized pathologic evaluation, accurate tumor size measurement, and reproducible tumor response grading to neoadjuvant therapy are needed for optimal patient care. The criteria and discussions provided here may provide guidance towards these goals.

Standardizing Pathologic Evaluation of Breast Carcinoma After Neoadjuvant Chemotherapy

CONTEXT.—

Neoadjuvant systemic therapy refers to the use of systemic agent(s) for malignancy prior to surgical treatment and has recently emerged as an option for most breast cancer patients eligible for adjuvant systemic therapy. Consequently, treated breast carcinomas have become routine specimens in pathology practices. A standard protocol has not yet been universally adopted for the evaluation and reporting of these specimens. The American Joint Committee on Cancer staging system recognizes the challenges in staging breast carcinomas after neoadjuvant treatment and provides important data points but does not currently provide detailed guidance in estimating the residual tumor burden in the breast and lymph nodes. The Residual Cancer Burden system is the only Web-based system that quantifies treatment response as a continuous variable using residual tumor burden in the breast and the lymph nodes.

OBJECTIVE.—

To provide clarifications and guidance for evaluation and reporting of postneoadjuvant breast specimens, discuss issues with the current staging and reporting systems, and provide specific suggestions for future modifications to the American Joint Committee on Cancer system and the Residual Cancer Burden calculator.

DATA SOURCES.—

English-language literature on the subject and the data from the I-SPY 2, a multicenter, adaptive randomization phase 2 neoadjuvant platform trial for early-stage, high-risk breast cancer patients.

CONCLUSIONS.—

This article highlights challenges in the pathologic evaluation and reporting of treated breast carcinomas and provides recommendations and clarifications for pathologists and clinicians. It also provides specific recommendations for staging and discusses future directions.

Reconstructing virtual large slides can improve the accuracy and consistency of tumor bed evaluation for breast cancer after neoadjuvant therapy

BACKGROUND

To explore whether the "WSI Stitcher", a program we developed for reconstructing virtual large slide through whole slide imaging fragments stitching, can improve the efficiency and consistency of pathologists in evaluating the tumor bed after neoadjuvant treatment of breast cancer compared with the conventional methods through stack splicing of physical slides.

METHODS

This study analyzed the advantages of using software-assisted methods to evaluate the tumor bed after neoadjuvant treatment of breast cancer. This new method is to use "WSI Stitcher" to stitch all the WSI fragments together to reconstruct a virtual large slide and evaluate the tumor bed with the help of the built-in ruler and tumor proportion calculation functions.

RESULTS

Compared with the conventional method, the evaluation time of the software-assisted method was shortened by 35%(P < 0.001). In the process of tumor bed assessment after neoadjuvant treatment of breast cancer, the software-assisted method has higher intraclass correlation coefficient when measuring the length (0.994 versus 0.934), width (0.992 versus 0.927), percentage of residual tumor cells (0.947 versus 0.878), percentage of carcinoma in situ (0.983 versus 0.881) and RCB index(0.997 versus 0.772). The software-assisted method has higher kappa values when evaluating tumor staging(0.901 versus 0.687) and RCB grading (0.963 versus 0.857).

CONCLUSION

The "WSI Stitcher" is an effective tool to help pathologists with the assessment of breast cancer after neoadjuvant treatment.

Neoadjuvant Therapy in Breast Cancer: Histologic Changes and Clinical Implications

Cytotoxic or endocrine therapy before surgery (neoadjuvant) for breast cancer has become standard of care, affording the opportunity to assess and quantify response in the subsequent resection specimen. Correlation with radiology, cassette mapping, and histologic review with a semi-quantitative reporting system such as residual cancer burden (RCB) provides important prognostic data that may guide further therapy. The tumor bed should be identified histologically, often as a collagenized zone devoid of normal breast epithelium, with increased vasculature. Identification of residual treated carcinoma may require careful high power examination, as residual tumor cells may be small and dyscohesive; features are widely variable and include hyperchromatic small, large, or multiple nuclei with clear, foamy, or eosinophilic cytoplasm. Calculation of RCB requires residual carcinoma span in 2 dimensions, estimated carcinoma cellularity (% area), number of involved lymph nodes, and span of largest nodal carcinoma. These RCB parameters may differ from AJCC staging measurements, which depend on only contiguous carcinoma in breast and lymph nodes.

Exploring the influencing factors of the pathologic complete response in estrogen receptor-positive, HER2-negative breast cancer after neoadjuvant chemotherapy: a retrospective study

Background

Pathological complete response (pCR) is the goal of neoadjuvant chemotherapy (NACT). We aimed to develop a nomogram to predict the probability of achieving pCR in estrogen receptor-positive (ER+), HER2-negative (HER2−) breast cancer patients.

Methods

A total of 273 ER+, HER2− breast cancer patients who received 4 cycles of thrice-weekly standard NACT in the First Affiliated Hospital of Chongqing Medical University were retrospectively enrolled. Univariate and multivariate logistic regression analyses were used to screen the predictive factors to develop the nomograms. The discrimination and calibration abilities were assessed by the C-index, receiver operating characteristic curve (AUC), and calibration plot.

Results

There were 28 patients (10.3%) with overall pCR, 38 patients (13.9%) with breast pCR after NACT. ER expression, PgR expression, the neutrophil-to-lymphocyte ratio (NLR) and the Ki-67 index were independent predictive factors for achieving overall pCR. These indicators had good discrimination and calibration ability (AUC 0.843). The nomogram for breast pCR was established based on ER expression, PgR expression, the NLR, and the Ki-67 index and showed great discriminatory ability, with an AUC of 0.810. The calibration curve showed that the predictive ability of the nomogram was a good fit to actual observations.

Conclusion

The nomograms exhibited a sufficient discriminatory ability for predicting pCR after NACT in ER+, HER2− breast cancer patients. Utilizing these nomograms will enable us to identify patients at high probability for pCR after NACT and provide a reference for preoperative adjuvant therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02492-7.

Pathologic evaluation of specimens after neoadjuvant chemotherapy in breast cancer: Current recommendations and challenges

Neoadjuvant chemotherapy is increasingly used to optimize breast conservation surgery and is becoming a standard of care in a subset of breast cancer patients. An accurate pathologic assessment is crucial in guiding clinical decisions and subsequent management and prognosis. This review aims to summarize the most current literature, recommendations, and challenges in the pathologic evaluation of breast cancer after neoadjuvant chemotherapy. Included are the most current definitions of the different types of tumor response, the underlying factors that can affect tumor response, how to assess lymph nodes, margins, and tumor markers post-neoadjuvant chemotherapy, as well as the different classification systems a pathologist can use to assess residual disease. In this era of de-escalation of surgical treatment, studies on imaging techniques to assess residual disease and avoid surgery after neoadjuvant chemotherapy have also been done. However, at least for now, surgical treatment remains the preferred practice. As such, pathologists play an increasingly critical role in standardizing assessment of residual disease post-neoadjuvant chemotherapy, and in optimizing the knowledge gained by this approach to breast cancer therapy.

Role and evaluation of pathologic response in early breast cancer specimens after neoadjuvant therapy: consensus statement

Pathologic evaluation of early breast cancer after neoadjuvant therapy is essential to provide prognostic information based on tumor response to treatment (pathologic complete response [pCR] or non-pCR) and to inform therapy decisions after surgery. To harmonize the pathologist’s handling of surgical specimens after neoadjuvant therapy, a panel of experts in breast cancer convened to developed a consensus on six main topics: (1) definition of pCR, (2) required clinical information, (3) gross examination and sampling, (4) microscopic examination, (5) evaluation of lymph node status, and (6) staging of residual breast tumor. The resulting consensus statements reported in this document highlight the role of an accurate evaluation of tumor response and define the minimum requirements to standardize the assessment of breast cancer specimens after neoadjuvant therapy.

Nomogram for predicting axillary lymph node pathological response in node-positive breast cancer patients after neoadjuvant chemotherapy

Background:

Pathological complete response (pCR) of axillary lymph nodes (ALNs) is frequently achieved in patients with clinically node-positive breast cancer after neoadjuvant chemotherapy (NAC), and ALN status is an important prognostic factor for breast cancer patients. This study aims to develop a new predictive clinical model to assess the ALN pCR rate after NAC.

Methods:

This was a retrospective series of 467 patients who had biopsy-proven positive ALNs at diagnosis and underwent ALN dissection from 2007 to 2014 at the National Cancer Center/Cancer Hospital of the Chinese Academy of Medical Sciences. We analyzed the clinicopathologic features of the patients and developed a nomogram to predict the probability of ALN pCR. A multivariable logistic regression stepwise model was used to construct a nomogram to predict ALN pCR in node-positive patients. The adjusted area under the receiver operating characteristic curve (AUC) was calculated to quantify the ability to rank patients by risk. Internal validation was performed using the 50/50 hold-out validation method. The nomogram was externally validated with prospective cohorts of 167 patients from 2016 to 2018 at the Cancer Hospital of the Chinese Academy of Medical Sciences and 114 patients from 2018 to 2020 at Beijing Tiantan Hospital.

Results:

In this retrospective study, 115 (24.6%) patients achieved ALN pCR after NAC. Multivariate analysis showed that clinical tumor stage (Odds ratio [OR]: 0.321, 95% confidence interval [CI]: 0.121–0.856; P = 0.023); primary tumor response (OR: 0.189; 95% CI: 0.123–0.292; P < 0.001), and estrogen receptor status (OR: 0.530, 95% CI: 0.304–0.925; P = 0.025) were independent predictors of ALN pCR. The nomogram was constructed based on the result of multivariate analysis. In the internal validation of performance of nomogram, the AUCs for the training and test sets were 0.719 and 0.753, respectively. The nomogram was validated in external cohorts with AUCs of 0.720, which demonstrated good discriminatory power in these data sets.

Conclusion:

We developed a nomogram to predict the likelihood of axillary pCR in node-positive breast cancer patients after NAC. The predictive model performed well in multicenter prospective external validation. This practical tool could provide information to surgeons regarding whether to perform additional ALN dissection after NAC.

Trial registration:

ChiCTR.org.cn, ChiCTR1800014968.

Prognostic significance of occult lymph node metastases in breast cancer: a meta-analysis

Background

Occult metastases in axillary lymph nodes have been reported to be associated with poor prognosis in patients with breast cancer. However, studies on the prognostic value of occult metastases have shown controversial results. This meta-analysis aimed to evaluate the prognostic significance of occult lymph node metastases in breast cancer.

Methods

Studies published until May, 2020, which retrospectively examined negative lymph nodes by stepsectioning and/or immunohistochemistry, were retrieved from MEDLINE, EMBASE, CNKI, and Cochrane Library databases. The pooled Relative Risk (RR) with 95% confidence interval (95% CI) for overall survival (OS) and disease-free survival (DFS) were calculated to examine the associations between occult metastases and prognosis.

Results

Patients with occult metastases in axillary lymph nodes had poorer five-year DFS (RR = 0.930; 95% CI = 0.907–0.954) and OS (RR = 0.972; 95% CI = 0.954–0.990). Furthermore, the DFS (RR = 0.887; 95% CI = 0.810–0.972) and OS (RR = 0.896; 95% CI = 0.856–0.939) of patients with occult metastases were significantly lower after a ten-year follow-up.

Conclusions

Occult metastases in the axillary lymph nodes are associated with poorer DFS andOS of patients with breast cancer. Occult metastases might serve as a predictive factor of survival outcomes in patients with breast cancer.

Sentinel lymph node assessment in breast cancer-an update on current recommendations

Sentinel lymph node biopsy (SLNB) has become the preferred method of surgical pathological nodal staging of early breast cancer by the end of the nineties. As the most likely sites of metastasis, the SLNs allow a more precise staging, and indeed gross sectioning, step sectioning, immunohistochemistry, and molecular staging methods have been used to disclose metastatic involvement of these lymph nodes. This review summarizes the backgrounds of SLNB, trends in related surgery and pathology. It also gives an insight into European National recommendations related to SLN and divergent daily practices in European pathology departments, on the basis of replies to questionnaires from 84 pathologists from 38 European countries. The questionnaires revealed the post-neoadjuvant setting as an area where a significant minority of pathologists report less confidence in classifying residual nodal involvement into TNM categories. The review also summarizes the neoadjuvant therapy-related aspects of SLNB.

Thermo Mammogram as a Tool to Assess Response to Neoadjuvant Chemotherapy in Breast Carcinoma

Introduction: Response to neoadjuvant chemotherapy (NACT) is predicted by clinical examination alone in locally advanced breast carcinoma. This study uses thermo mammogram (TMG) to assess the response. Aim and Objectives: The aim is to study TMG changes during NACT in breast cancer and predict response to NACT in locally advanced carcinoma and to compare clinical response with TMG response/changes in any form. Patients and Methods: All patients with locally advanced breast cancer who had treated with NACT were included in this study. Baseline TMG picture was taken using illumina360° (digital robotic rotational thermography device for 360 degree view of each breast) system before chemotherapy. TMG was repeated before next cycle. All patients were also assessed clinically during and after each cycle of chemotherapy. To assess the potential of TMG in predicting tissue response to chemotherapy, the precool, postcool, and the temperature difference between precool and postcool before every cycle were analyzed. Results: A total of 19 patients were analyzed. Eight patients had complete clinical response, six patients had partial response, and five patients had static disease. Median of precool, temperature difference between precool and postcool for patients between no response and complete response did not show statistically significant difference. However, the median of postcool spot temperature showed statistically significant difference. Median of postcool temperature difference for patients between partial response and complete response showed statistically significant difference. The median of postcool spot temperature for patients with no response and partial response did not show statistically significant difference. Precool temperature difference for all the visits showed no statistically significant difference. Conclusion: This preliminary study suggests that the TMG has potential for monitoring NACT response in breast cancer patients. Postcool temperature measurement is an early indicator of response to NACT.

Can one stop nucleic acid sampling (OSNA) predict nodal positivity following neoadjuvant chemotherapy? A prospective cohort study of 293 patients

Until recently, axillary node clearance had long been the standard of care in patients with axillary node-positive disease. One stop nucleic acid sampling (OSNA) has been used to guide intraoperative decision-making regarding suitability for axillary node clearance (ANC). The aim of this study is to evaluate the use of OSNA following neoadjuvant chemotherapy (NACT) and whether it can predict lymph node burden in ANC. A single center, prospective cohort study was performed on 297 patients having OSNA between 2016 and 2019. Patients were sub-classified according to node positivity at diagnosis and those treated with NACT and outcomes included copy number and lymph node harvest. Axillary complete pathological response was observed in 24/36 patients (67%) following NACT. 14/16 patients (87%) having axillary node clearance had axillary node disease limited to 4 nodes. OSNA copy numbers were significantly higher in patients showing disease progression following NACT. Overall, 73% of patients with lymph node positivity at diagnosis could be successfully treated with a combination of NACT and lymph node excision of four nodes. De-escalating axillary surgical treatment to resection of four nodes following NACT may be effective in balancing oncological resection and limiting treatment morbidity. ONSA can correctly identify patients experiencing disease progression who would benefit from traditional three-level ANC.

Diagnostic Performance of Noninvasive Imaging for Assessment of Axillary Response After Neoadjuvant Systemic Therapy in Clinically Node-positive Breast Cancer: A Systematic Review and Meta-analysis

OBJECTIVE

The purpose of this study was to perform a systematic review and meta-analysis to determine the diagnostic performance of current noninvasive imaging modalities for assessment of axillary response after neoadjuvant systemic therapy (NST) in clinically node-positive breast cancer patients.

SUMMARY OF BACKGROUND DATA

NST can lead to downstaging of axillary lymph node disease. Imaging can potentially provide information about the axillary response to NST and, consequently, tailor the surgical management.

METHODS

PubMed and Embase were searched for studies that compared noninvasive imaging after NST with axillary surgery outcome to identify axillary response in patients with initial pathologically proven axillary lymph node metastasis. Two reviewers independently screened the studies and extracted the data. A meta-analysis was performed by computing the pooled sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Thirteen studies describing 2380 patients were included for final analysis. Of these patients, 1322 had undergone axillary ultrasound, 849 breast MRI, and 209 whole-body 18F-FDG PET-CT. The overall axillary pathologic complete response rate was 39.5% (941/2380). For axillary ultrasound, the pooled sensitivity, specificity, PPV, and NPV were 65%, 69%, 77%, 50%, respectively. For breast MRI, the pooled sensitivity, specificity, PPV, and NPV were 60%, 76%, 78%, 58%, respectively. For whole-body 18F-FDG PET-CT, the pooled sensitivity, specificity, PPV, and NPV were 38%, 86%, 78%, 49%, respectively.

CONCLUSIONS

The diagnostic performance of current noninvasive imaging modalities is limited to accurately assess axillary response after NST in clinically node-positive breast cancer patients.

Neoadjuvant radiotherapy for locally advanced and high-risk breast cancer

INTRODUCTION

Neoadjuvant radiotherapy (NART) as part of a multi-modality approach for locally advanced breast cancer (LABC) requires further investigation. Importantly, this approach may allow for a single-staged surgical procedure, with mastectomy and immediate autologous reconstruction. Multiple other potential benefits of NART include improved pathological downstaging of breast disease, reduced overall treatment time, elimination of time period with breast tissue deficit and improved patient satisfaction.

METHODS

This is a retrospective multi-institutional review of patients with LABC and high-risk breast disease undergoing NART. Eligible patients sequentially underwent neoadjuvant chemotherapy (NACT) with or without HER2-targeted therapy, NART, followed by mastectomy with immediate autologous breast reconstruction (BR) 4- to 6 weeks post-completion of radiotherapy. Patient and tumour characteristics were analysed using descriptive statistics. Surgical complications were assessed using the Clavien-Dindo Classification (Ann Surg 2004; 240: 205).

RESULTS

From 3/2013 to 9/2019, 153 patients were treated with NART. The median age was 47 years (IQR 42-52), with median body mass index of 27. Eighteen patients experienced Grade 3 acute surgical complications. This included 13 Grade 3B breast-site events and 9 Grade 3B donor-site events, where further surgical intervention was required for management of wound infection, wound dehiscence, flap or mastectomy skin necrosis, haematoma and internal mammary venous anastomotic thrombosis. No autologous flap loss was observed.

CONCLUSION

Neoadjuvant radiotherapy facilitates a single-stage surgical procedure with mastectomy and immediate autologous BR, eliminating the delay to reconstructive surgery and thus shortening a woman's breast cancer journey. The findings of this review support the use of NART, with comparable rates of surgical complications to standard sequencing.

Factors Associated with Nodal Pathologic Complete Response Among Breast Cancer Patients Treated with Neoadjuvant Chemotherapy: Results of CALGB 40601 (HER2+) and 40603 (Triple-Negative) (Alliance)

BACKGROUND

De-escalation of axillary surgery after neoadjuvant chemotherapy (NAC) requires careful patient selection. We seek to determine predictors of nodal pathologic complete response (ypN0) among patients treated on CALGB 40601 or 40603, which tested NAC regimens in HER2+ and triple-negative breast cancer (TNBC), respectively.

PATIENTS AND METHODS

A total of 760 patients with stage II-III HER2+ or TNBC were analyzed. Those who had axillary surgery before NAC (N = 122), or who had missing pretreatment clinical nodal status (cN) (N = 58) or ypN status (N = 41) were excluded. The proportion of patients with ypN0 disease was estimated for those with and without breast pathologic complete response (pCR) according to pretreatment nodal status.

RESULTS

In 539 patients, the overall ypN0 rate was 76.3% (411/539) to 93.2% (245/263) in patients with breast pCR and 60.1% (166/276) with residual breast disease (RD) (P < 0.0001). For patients who were cN0 pretreatment, the ypN0 rate was 88.8% (214/241), 96.3% (104/108) with breast pCR, and 82.7% (110/133) with RD. For patients who were cN1, 66.2% (157/237) converted to ypN0, 91.7% (111/121) with breast pCR and 39.7% (46/116) with RD. For patients who were cN2/3, 65.6% (40/61) converted to ypN0, 88.2% (30/34) with breast pCR and 37.0% (10/27) with RD. On multivariable analysis, only pretreatment clinical nodal status and breast pCR/RD were associated with ypN0 status (both P < 0.0001).

CONCLUSIONS

Breast pCR and pretreatment nodal status are predictive of ypN0 axillary nodal involvement, with < 5% residual nodal disease among cN0 patients who experience breast pCR. These findings support the incorporation of axillary surgery de-escalation strategies into NAC trials.

Predicting Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer After the Second Cycle of Chemotherapy Using Shear-Wave Elastography-A Preliminary Evaluation

ABSTRACT

The primary objective of the study was to determine whether shear wave elastography can be used to predict the response of neoadjuvant chemotherapy (NACT) in women having invasive breast cancer. A prospective study involving 28 patients having invasive breast cancer and undergoing NACT followed by surgery was done after institutional review board approval. All the patients underwent 2-dimensional B-mode ultrasound and 2-dimensional shear wave elastography before the start of chemotherapy and after 2 cycles of completion of chemotherapy, and mean stiffness was recorded. The patients were segregated to responders and nonresponders based on residual cancer burden scoring. Difference in mean elasticity was compared between the 2 groups. The results showed that the mean stiffness after 2 cycles was significantly different between the responders and nonresponders and so was the change in the mean stiffness after 2 cycles of NACT. Using a cutoff value of 45.5 kPa (20.53%), change in mean elasticity after 2 cycles of NACT, sensitivity of 76.9%, and specificity of 80% with negative predictive value of 80.1 was attained. Responders show greater change in mean stiffness after 2 cycles of NACT as compared with nonresponders on shear wave elastography; thus, it can be used to predict response to NACT after 2 cycles.

Standardized pathology report for breast cancer

Given the recent advances in management and understanding of breast cancer, a standardized pathology report reflecting these changes is critical. To meet this need, the Breast Pathology Study Group of the Korean Society of Pathologists has developed a standardized pathology reporting format for breast cancer, consisting of 'standard data elements,' 'conditional data elements,' and a biomarker report form. The 'standard data elements' consist of the basic pathologic features used for prognostication, while other factors related to prognosis or diagnosis are described in the 'conditional data elements.' In addition to standard data elements, all recommended issues are also presented. We expect that this standardized pathology report for breast cancer will improve diagnostic concordance and communication between pathologists and clinicians, as well as between pathologists inter-institutionally.

Standardized Pathology Report for Breast Cancer

Given the recent advances in management and understanding of breast cancer, a standardized pathology report reflecting these changes is critical. To meet this need, the Breast Pathology Study Group of the Korean Society of Pathologists has developed a standardized pathology reporting format for breast cancer, consisting of ‘standard data elements,’ ‘conditional data elements,’ and a biomarker report form. The ‘standard data elements’ consist of the basic pathologic features used for prognostication, while other factors related to prognosis or diagnosis are described in the ‘conditional data elements.’ In addition to standard data elements, all recommended issues are also presented. We expect that this standardized pathology report for breast cancer will improve diagnostic concordance and communication between pathologists and clinicians, as well as between pathologists inter-institutionally.

Neoadjuvant Chemotherapy for Breast Cancer: Past, Present, and Future

Neoadjuvant chemotherapy (NAC) had been developed as a systematic approach before definitive surgery for the treatment of locally advanced or inoperable breast cancer such as inflammatory breast cancer in the past. In addition to its impact on surgery, the neoadjuvant setting has a benefit of providing the opportunity to monitor the individual drug response. Currently, the subject of NAC has expanded to include patients with early-stage, operable breast cancer because it is revealed that the achievement of a pathologic complete response (pCR) is associated with excellent long-term outcomes, especially in patients with aggressive phenotype breast cancer. In addition, this approach provides the unique opportunity to escalate adjuvant therapy in those with residual disease after NAC. Neoadjuvant chemotherapy in breast cancer is a rapidly evolving topic with tremendous interest in ongoing clinical trials. Here, we review the improvements and further challenges in the NAC setting in translational breast cancer research.

Management of the axilla with sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer: A single-center study

The neoadjuvant chemotherapy (NAC) is the gold standard initial treatment of the locally advanced breast cancer (LABC). However, the reliability of methods that used to assess response the NAC is still controversial. In this study, patients with LABC who underwent NAC were evaluated retrospectively. The assessment of response to NAC and the effect of axillary approach were investigated on LABC course.The study comprised 94 patients who received NAC with an LABC diagnosis between 2008 and 2020. In our center, magnetic resonance imaging, ultrasonography, and F-flouro deoxyglucose positron emission tomography/computed tomography, and, for some patients, fine-needle aspiration biopsy of suspicious axillary lymph nodes have been performed to assess the effects of NAC. Patients with positive hormone receptor status received adjuvant hormonotherapy, and those with human epidermal growth factor receptor 2 gene expression were treated with trastuzumab. Adjuvant radiotherapy was applied to all patients undergoing breast conserving surgery. Radiotherapy was applied to the peripheral lymphatic areas in the clinical N1 to N3 cases regardless of the response to NAC.The clinical response to the NAC was found that partial in 59% and complete in 19% of the patients. However, 21.2% of the patients were unresponsive. The mean of lymph nodes that excised with the procedure of sentinel lymph node biopsy (SLNB) was 2.4 (range 1-7). In 22 of the 56 patients who underwent SLNB, axillary dissection (AD) was added to the procedure upon detection of metastasis in frozen section examinations. There was no difference between the SLNB and AD groups regarding overall survival (OS; P = .472) or disease-free survival (DFS) rates (P = .439). However, there were differences in the OS (P < .05) and DFS (P = .05) rates on the basis of the LABC histopathological subtypes.The study found that a relationship between molecular subtypes and LABC survival. However, the post-NAC axillary approach had no effect on OS or DFS. Therefore, multiple imaging and interventional methods are needed for the evaluation of NAC response. In addition, morbidity can be avoided after AD by the use of SLNB in cN0 patients.