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RNA sequencing (RNAseq) analysis is emerging as a clinical research or diagnostic approach for cytologic samples, but there is need for formal comparison of different sample preparation methods in the cytology laboratory to identify which pre-analytic methods could provide alternatives to formalin-fixed paraffin-embedded (FFPE) sections. We prepared 13 malignant effusions (metastatic estrogen receptor-positive breast cancer) in the cytology laboratory using 6 routine cytologic methods: FFPE cell block, Carnoy's solution, 95% ethanol (EtOH), air-dried and Diff-Quik, ThinPrep, and SurePath preparations. Measurements of RNA quality, expression of 2 multigene expression signatures, molecular subtype, and 4 common activating mutation sites in each preparation were compared with fresh frozen (FF) cell pellet in RNA preservative using distribution of fragment length and concordance correlation coefficient (CCC). The fraction of RNA fragments measuring 200 bases or more (DV200) were 24% higher from cytospins fixed in Carnoy's solution or 95% EtOH than DV200 from FFPE cell blocks. SurePath samples failed RNAseq quality control. There was high concordance of gene expression measurements with FF samples using cytospins fixed in Carnoy's solution, 95% EtOH, Diff-Quik (CCC = 0.829, 0.812, 0.760, respectively), or ThinPrep (CCC = 0.736), but lower using FFPE cell block (CCC = 0.564). The proportion of mutant transcripts was concordant between FF and any cytologic preparation methods. Cytospin preparations fixed with Carnoy's or 95% ETOH then Papanicolaou stained produced RNAseq results that were equivalent to FF samples and superior to FFPE cell block sections. • Routine cytologic slide preparations can produce RNA sequencing results that are superior to formalin-fixed paraffin-embedded cell block preparations. • Cytology effusion specimens can be a source of high quantity and quality material for RNA sequencing analysis. • This information is critically important as cancer treatments are trending towards personalized, targeted therapies. [ABSTRACT FROM AUTHOR]

Summary: In this Personal View, we outline proposals for uniform collection of biospecimens obtained in neoadjuvant breast cancer trials undertaken by the Breast International Group (BIG) and the National Cancer Institute-sponsored North American Breast Cancer Group (NABCG). These proposals aim to standardise collection of high-quality specimens, with respect to both type and timing, to enhance and allow integration of results obtained from neoadjuvant trials done by several groups. They should be considered in parallel with recommendations for tissue-specimen collection and handling previously developed by BIG and NABCG. We propose that tumour tissue (formalin-fixed, paraffin-embedded and samples dedicated for molecular studies) should be taken at baseline, 1–3 weeks after the start of treatment, and at definitive surgery, with clear prioritisation in the study protocol of number, order, and preservation of samples to be gathered. This step should be accompanied by blood collection (plasma, serum, and whole blood) whenever possible. We advocate strongly a move towards one diagnostic and research biopsy procedure in all women with breast cancers potentially suitable for neoadjuvant treatment. If possible, patients should be referred at the outset to specialised centres to give them the opportunity to participate in neoadjuvant clinical trials, thereby avoiding several biopsy procedures. [ABSTRACT FROM AUTHOR]

Background: HER2-targeted treatments have improved outcomes in patients with HER2-positive breast cancer in the neoadjuvant, adjuvant, and metastatic settings; however, some patients remain at risk of relapse or death for many years after treatment of early-stage disease. Therefore, new strategies are needed. We did a phase 3 trial to assess a neoadjuvant regimen for HER2-positive breast cancer that replaces traditional systemic chemotherapy with targeted treatment.Methods: We did a randomised, open-label phase 3 KRISTINE trial in 68 Translational Research In Oncology centres (hospitals and specialty cancer centres in Asia, Europe, USA, and Canada). Eligible participants were aged 18 years or older with centrally confirmed HER2-positive stage II-III operable breast cancer (>2 cm tumour size), an Eastern Cooperative Oncology Group performance status of 0-1, and a baseline left ventricular ejection fraction of at least 55% (by echocardiogram or multiple-gated acquisition scan). We randomly assigned participants (1:1) to receive either trastuzumab emtansine plus pertuzumab or docetaxel, carboplatin, and trastuzumab plus pertuzumab. We did the randomisation via an interactive response system under a permuted block randomisation scheme (block size of four), stratified by hormone receptor status, stage at diagnosis, and geographical location. Patients received six cycles (every 3 weeks) of neoadjuvant trastuzumab emtansine plus pertuzumab (trastuzumab emtansine 3·6 mg/kg; pertuzumab 840 mg loading dose, 420 mg maintenance doses) or docetaxel, carboplatin, and trastuzumab plus pertuzumab (docetaxel 75 mg/m2; carboplatin area under the concentration-time curve 6 mg/mL × min; trastuzumab 8 mg/kg loading dose, 6 mg/kg maintenance doses) plus pertuzumab [same dosing as in the other group]). All treatments were administered intravenously. The primary objective was to compare the number of patients who achieved a pathological complete response (ypT0/is, ypN0), between groups in the intention-to-treat population (two-sided assessment), based on local evaluation of tumour samples taken at breast cancer surgery done between 14 days and 6 weeks after completion of neoadjuvant therapy. Safety was analysed in patients who received at least one dose of study medication. This trial is registered with ClinicalTrials.gov, number NCT02131064, and follow-up of the adjuvant phase is ongoing.Findings: Between June 25, 2014, and June 15, 2015, we randomly assigned 444 patients to neoadjuvant treatment with trastuzumab emtansine plus pertuzumab (n=223) or docetaxel, carboplatin, and trastuzumab plus pertuzumab (n=221). A pathological complete response was achieved by 99 (44·4%) of 223 patients in the trastuzumab emtansine plus pertuzumab group and 123 (55·7%) of 221 patients in the docetaxel, carboplatin, and trastuzumab plus pertuzumab group (absolute difference -11·3 percentage points, 95% CI -20·5 to -2·0; p=0·016). During neoadjuvant treatment, compared with patients receiving docetaxel, carboplatin, and trastuzumab plus pertuzumab, fewer patients receiving trastuzumab emtansine plus pertuzumab had a grade 3-4 adverse event (29 [13%] of 223 vs 141 [64%] of 219) or a serious adverse event (11 [5%] of 223 vs 63 [29%] of 219). The most common grade 3-4 adverse events in the trastuzumab emtansine plus pertuzumab group were decreased platelet count (three [1%] of 223 patients vs 11 [5%] of 219 with docetaxel, carboplatin, and trastuzumab plus pertuzumab), fatigue (three [1%] vs seven [3%]), alanine aminotransferase increase (three [1%] vs four [2%]), and hypokalaemia (three [1%] vs five [2%]). The most common grade 3-4 adverse events in the docetaxel, carboplatin, and trastuzumab plus pertuzumab group were neutropenia (55 [25%] of 219 vs one [<1%] of 223 with trastuzumab emtansine plus pertuzumab), diarrhoea (33 [15%] vs 2 [<1%]), and febrile neutropenia (33 [15%] vs 0). No deaths were reported during neoadjuvant treatment.Interpretation: Traditional neoadjuvant systemic chemotherapy plus dual HER2-targeted blockade (docetaxel, carboplatin, and trastuzumab plus pertuzumab) resulted in significantly more patients achieving a pathological complete response than HER2-targeted chemotherapy plus HER2-targeted blockade (trastuzumab emtansine plus pertuzumab); however, numerically more grade 3-4 and serious adverse events occurred in the chemotherapy plus trastuzumab and pertuzumab group. Further efforts to improve the efficacy of chemotherapy without imparting more toxicity are warranted.Funding: F Hoffmann-La Roche and Genentech. [ABSTRACT FROM AUTHOR]

Objective: Different molecular subtypes of triple-negative breast cancer (TNBC) have previously been identified through analysis of gene expression profiles. The luminal androgen receptor (LAR) subtype has been shown to have a lower rate of pathologic complete response to neoadjuvant chemotherapy than other TNBC subtypes. The purpose of this study was to determine if the imaging features of TNBCs differ by AR (androgen receptor) status, which is a surrogate immunohistochemical (IHC) marker for the chemoresistant LAR subtype of TNBC.Materials and Methods: This sub-study was part of a clinical trial in patients with stage I-III TNBC who were prospectively monitored for response while receiving neoadjuvant systemic therapy (NAST) at a single comprehensive cancer center. This interim imaging analysis included 144 patients with known AR status measured by IHC. AR-positive (AR+) tumors were defined as those in which at least 10% of tumor cells had positive nuclear AR staining. Two experienced, fellowship-trained breast radiologists who were blinded to the IHC results retrospectively reviewed and reached consensus on all imaging studies for the index lesion (i.e., mammogram, ultrasound, and breast magnetic resonance imaging). The index lesion for each patient was reviewed and described according to the fifth edition of the Breast Imaging Reporting and Data System lexicon. Logistic regression modeling was used to identify imaging features predictive of AR status. p ≤ 0.05 was considered statistically significant.Results: Univariate logistic regression models for AR status showed that AR+ TNBC was significantly associated with heterogeneously dense breast composition on mammography (p = 0.02), mass with calcifications (p = 0.05), irregular mass shape on mammography (p = 0.03), and irregular mass shape on sonography (p = 0.003). Multivariate logistic regression models for AR status showed that AR+ TNBC was significantly associated with heterogeneously dense breast composition on mammography (p = 0.01), high mass density on mammography (p = 0.003), and irregular mass shape on sonography (p = 0.0004).Conclusion: The imaging features of TNBCs differ by AR status. Multimodality breast imaging may help identify the LAR subtype of TNBC, which has been shown to be a subtype that is relatively resistant to neoadjuvant chemotherapy. [ABSTRACT FROM AUTHOR]

Background: Although several randomised trials in patients with triple-negative breast cancer have shown that the addition of carboplatin, with or without poly(ADP-ribose) polymerase (PARP) inhibitors, to neoadjuvant chemotherapy increases the likelihood of achieving a pathological complete response, the use of these therapies in this setting has remained controversial. The BrighTNess trial was designed to assess the addition of the PARP inhibitor veliparib plus carboplatin or carboplatin alone to standard neoadjuvant chemotherapy in triple-negative breast cancer.Methods: We did a phase 3, randomised, double-blind, placebo-controlled trial (BrighTNess) across 145 sites in 15 countries. Patients aged 18 years and older with previously untreated histologically or cytologically confirmed clinical stage II-III triple-negative breast cancer, who were candidates for potentially curative surgery and had an Eastern Cooperative Oncology Group performance status of 0 or 1, were randomly assigned (2:1:1) by an interactive response technology system via permuted blocks (block size of four) within strata to receive one of three segment 1 regimens: paclitaxel (80 mg/m2 intravenously weekly for 12 doses) plus carboplatin (area under the curve 6 mg/mL per min, intravenously every 3 weeks, for four cycles) plus veliparib (50 mg orally, twice a day); paclitaxel plus carboplatin plus veliparib placebo (twice a day); or paclitaxel plus carboplatin placebo (every 3 weeks for four cycles) plus veliparib placebo. Following segment 1, all patients were assigned to segment 2 in which they received doxorubicin and cyclophosphamide every 2-3 weeks for four cycles. Randomisation for segment 1 was stratified by germline BRCA mutation status, nodal stage, and planned schedule of doxorubicin and cyclophosphamide administration. The primary endpoint was pathological complete response in breast and lymph nodes as determined by site pathologists following completion of neoadjuvant therapy. Efficacy analyses were done by intention to treat and safety analyses included all patients who received at least one dose of study treatment. These are the first results of an ongoing clinical trial; the data cutoff for the analyses presented was Dec 8, 2016. This study is registered with ClinicalTrials.gov, number NCT02032277.Findings: Between April 4, 2014, and March 18, 2016, 634 patients were randomly assigned: 316 to paclitaxel plus carboplatin plus veliparib, 160 to paclitaxel plus carboplatin, and 158 to paclitaxel alone. The proportion of patients who achieved a pathological complete response was higher in the paclitaxel, carboplatin, and veliparib group than in patients receiving paclitaxel alone (168 [53%] of 316 patients vs 49 [31%] of 158, p<0·0001), but not compared with patients receiving paclitaxel plus carboplatin (92 [58%] of 160 patients, p=0·36). Grade 3 or 4 toxicities, and serious adverse events were more common in patients receiving carboplatin, whereas veliparib did not substantially increase toxicity. The most common grade 3 or 4 events overall were neutropenia (352 [56%] of 628 patients), anaemia (180 [29%]), and thrombocytopenia (75 [12%]) through complete treatment, and febrile neutropenia (88 [15%] of 601 patients) during segment 2. The most common serious adverse events were febrile neutropenia (80 [13%] of 628 patients) and anaemia (20 [3%]).Interpretation: Although the addition of veliparib and carboplatin to paclitaxel followed by doxorubicin and cyclophosphamide improved the proportion of patients with triple-negative breast cancer who achieved a pathological complete response, the addition of veliparib to carboplatin and paclitaxel did not. Increased toxicities with the addition of carboplatin (with or without veliparib) to paclitaxel were manageable and did not substantially affect treatment delivery of paclitaxel followed by doxorubicin and cyclophosphamide. Given the consistent results with previous studies, the addition of carboplatin appears to have a favourable risk to benefit profile and might be considered as a potential component of neoadjuvant chemotherapy for patients with high-risk, triple-negative breast cancer.Funding: AbbVie. [ABSTRACT FROM AUTHOR]

Summary: Background: Addition of taxanes to preoperative chemotherapy in breast cancer increases the proportion of patients who have a pathological complete response (pCR). However, a substantial proportion of patients do not respond, and the prognosis is particularly poor for patients with oestrogen-receptor (ER)/progesterone-receptor (PR)/human epidermal growth factor receptor 2 (HER2; ERBB2)-negative (triple-negative) disease who do not achieve a pCR. Reliable identification of such patients is the first step in determining who might benefit from alternative treatment regimens in clinical trials. We previously identified genes involved in mitosis or ceramide metabolism that influenced sensitivity to paclitaxel, with an RNA interference (RNAi) screen in three cancer cell lines, including a triple-negative breast-cancer cell line. Here, we assess these genes as a predictor of pCR to paclitaxel combination chemotherapy in triple-negative breast cancer. Methods: We derived a paclitaxel response metagene based on mitotic and ceramide genes identified by functional genomics studies. We used area under the curve (AUC) analysis and multivariate logistic regression to retrospectively assess the metagene in six cohorts of patients with triple-negative breast cancer treated with neoadjuvant chemotherapy; two cohorts treated with paclitaxel (n=27, 30) and four treated without paclitaxel (n=88, 28, 48, 39). Findings: The metagene was associated with pCR in paclitaxel-treated cohorts (AUC 0·79 [95% CI 0·53–0·93], 0·72 [0·48–0·90]) but not in non-paclitaxel treated cohorts (0·53 [0·31–0·77], 0·59 [0·22–0·82], 0·53 [0·36–0·71], 0·64 [0·43–0·81]). In multivariate logistic regression, the metagene was associated with pCR (OR 19·92, 2·62–151·57; p=0·0039) with paclitaxel-containing chemotherapy. Interpretation: The paclitaxel response metagene shows promise as a paclitaxel-specific predictor of pCR in patients with triple-negative breast cancer. The metagene is suitable for development into a reverse transcription-PCR assay, for which clinically relevant thresholds could be established in randomised clinical trials. These results highlight the potential for functional genomics to accelerate development of drug-specific predictive biomarkers without the need for training clinical trial cohorts. Funding: UK Medical Research Council; Cancer Research UK; the National Institute for Health Research (UK); the Danish Council for Independent Research-Medical Sciences (FSS); Breast Cancer Research Foundation (New York); Fondation Luxembourgeoise contre le Cancer; the Fonds National de la Recherche Scientifique; Brussels Region (IRSIB-IP, Life Sciences 2007) and Walloon Region (Biowin-Keymarker); Sally Pearson Breast Cancer Fund; and the European Commission. [Copyright &y& Elsevier]

Abstract: Background: Mucinous, medullary, and tubular carcinomas are uncommon types of breast cancer whose rarity does not permit large single-institution studies or randomized trials to define optimal treatments. In this study, we evaluated the long-term outcomes of breast-conserving therapy (BCT) for these subtypes of breast cancer and compared them with those for invasive ductal carcinoma. Methods: In our institutional database of patients who received BCT from 1965 to 1999, 1,643 patients with stage I to II mucinous (61), medullary (37), tubular (60), and invasive ductal (1,485) histologies were identified. The clinical and pathologic features of the 4 groups were evaluated and compared with respect to local-regional recurrence rates, disease-free survival, and overall survival (OS). Results: No statistically significant differences were found in the local-regional failure rate among the 4 groups (10.6-year median follow-up). Only patients with tubular carcinoma had better 5- and 10-year OS rates (P = .013). In multivariable analysis, factors associated with improved OS included age at or below 50 years, negative nodal status, use of chemotherapy or hormonal therapy, and tubular histology. Conclusions: BCT for mucinous, medullary, or tubular carcinoma resulted in similar local-regional failure rates to that for invasive ductal carcinoma. Tubular carcinoma patients had the most favorable OS. BCT is an appropriate treatment strategy for early-stage mucinous, medullary, and tubular carcinomas. [Copyright &y& Elsevier]

Summary: Background: Gene expression microarrays are being used to develop new prognostic and predictive tests for breast cancer, and might be used at the same time to confirm oestrogen-receptor status and ERBB2 status. Our goal was to establish a new method to assign oestrogen receptor and ERBB2-receptor status to breast carcinoma based on mRNA expression measured using Affymetrix U133A gene-expression profiling. Methods: We used gene expression data of 495 breast cancer samples to assess the correlation between oestrogen receptor (ESR1) and ERBB2 mRNA and clinical status of these genes (as established by immunohistochemical [IHC] or fluorescence in-situ hybridisation [FISH], or both). Data from 195 fine-needle aspiration (FNA) samples were used to define mRNA cutoff values that assign receptor status. We assessed the accuracy of these cutoffs in two independent datasets: 123 FNA samples and 177 tissue samples (ie, resected or core-needle biopsied tissues). Profiling was done at two institutions by use of the same platform (Affymetrix U133A GeneChip). All data were uniformly normalised with dCHIP software. Findings: ESR1 and ERBB2 mRNA levels correlated closely with routine measurements for receptor status in all three datasets. Spearman''s correlation coefficients ranged from 0·62 to 0·77. An ESR1 mRNA cutoff value of 500 identified oestrogen-receptor-positive status with an overall accuracy of 90% (training set), 88% (first validation set), and 96% (second validation set). An ERBB2 mRNA threshold of 1150 identified ERBB2-positive status with the overall accuracy of 93% (training set), 89% (first validation set), and 90% (second validation set). Reproducibility of mRNA measurements in 34 replicate experiments was high (correlation coefficient 0·975 for ESR1, 0·984 for ERBB2). Interpretation: Amounts of ESR1 and ERBB2 mRNA as measured by the Affymetrix GeneChip reliably and reproducibly establish oestrogen-receptor status and ERBB2 status, respectively. [Copyright &y& Elsevier]

Background: Lymphoscintigraphy (LSG) can identify lymphatic drainage patterns before sentinel lymph node (SLN) biopsy is performed in patients with early-stage breast cancer, but the importance of extraaxillary SLNs seen on LSG is unknown. We assessed whether drainage patterns seen on LSG were associated with histologic findings in axillary SLNs recovered at SLN biopsy. Study Design: From a prospectively maintained database, we identified 1,201 clinically node-negative patients with invasive breast cancer who underwent preoperative LSG and axillary SLN biopsy. Patient and tumor characteristics, LSG results, and final SLN pathology results were examined. Results: LSG showed drainage to internal mammary (IM) nodes in 1.6% of patients, axillary nodes in 68.1%, both IM and axillary nodes in 19.8%, and no drainage in 10.3%. Drainage to IM nodes was observed for tumors in all quadrants of the breast. Patients with IM drainage had a younger median age than patients without IM drainage (51.8 versus 58.3 years, respectively; p < 0.001). The intraoperative axillary SLN identification rate was higher when axillary drainage was observed on LSG than when it was not observed (98.7% versus 93.0%, respectively; p < 0.001), but the LSG drainage pattern was not associated with pathologic status of the SLN or number of metastatic SLNs. At a median followup of 32 months, 4 patients had regional nodal recurrence. Conclusions: Almost one-fourth of patients had lymphatic drainage to the extraaxillary lymph nodes, particularly the IM nodes, seen on LSG. Extraaxillary drainage seen on LSG did not preclude identification of axillary SLNs at operation. Longterm followup of patients with lymphoscintigraphic evidence of extraaxillary drainage is needed to determine whether regional and systemic recurrence patterns differ in these patients. [ABSTRACT FROM AUTHOR]

Background: The role of sentinel lymph node biopsy (SLNB) in patients with an initial diagnosis of ductal carcinoma in situ (DCIS) has not been well defined. The purpose of our study was to determine when the risk of finding invasive disease on final pathology in patients with an initial diagnosis of DCIS was sufficiently high to justify use of SLNB. Study Design: The records of 398 consecutive patients from our prospective database with an initial diagnosis of DCIS, treated between July 1999 and December 2002, were analyzed. Associations between clinical and pathologic factors and patient selection for SLNB and outcomes were analyzed for significance using univariate and multivariate analyses. Results: Of the 398 patients, 80 (20%) were found to have invasive disease on final pathology. Multivariate analysis revealed 4 independent predictors of invasive cancer on final pathology: 55 years of age or younger (odds ratio [OR], 2.19; p = 0.024), diagnosis by core-needle biopsy (OR, 3.76; p = 0.006), mammographic DCIS size of at least 4 cm (OR, 2.92; p = 0.001), and high-grade DCIS (OR, 3.06; p = 0.002). A total of 141 patients (35%) underwent SLNB as a component of their initial operation. Multivariate analysis revealed that the presence of comedonecrosis (OR, 2.69; p = 0.007) and larger mammographic DCIS size (OR, 1.18; p = 0.0002) were independent predictors of patients' undergoing SLNB. Of these 141 patients, 103 (73%) were diagnosed by core-needle biopsy, 42 (30%) had invasive disease on final pathology, and 14 (10%) had a positive sentinel lymph node: 12 (86%) by hematoxylin and eosin staining and 2 by immunohistochemistry. The only independent predictor of a positive SLN was the presence of a palpable tumor (OR, 4.28, p = 0.042). Of these 14 patients with a positive sentinel node, only 11 (79%) had invasive cancer on final pathology. Conclusions: SLNB should not be performed routinely for all patients with an initial diagnosis of DCIS. Risks and benefits of SLNB should be discussed with patients who are younger, are diagnosed by core-needle biopsy, or have large or high-grade DCIS. [ABSTRACT FROM AUTHOR]

Expression profiling using cDNA microarrays have redefined the molecular classification of some cancers. The comprehensive genetic analysis also permits the identification of novel pathways that might determine subtle differences in tumor phenotype. Herein, we analyzed the tissues from a patient with bilateral cancer of different histologies in each breast (pure invasive mucinous and pure invasive ductal), thus providing a unique opportunity to assess the expression profiles determined by histology in an isogenic human background. Our results show that the mucinous phenotype is associated with the expression of immunostimulatory and inhibitory genes, consistent with the cellular infiltration of lymphocytes and with the expression of enzymes involved in mucin production. Moreover, the panel of matrix metallo-proteinases are distinctly different between the mucinous and the invasive tumors, suggesting that therapeutic targets to this class of compounds may need to be tailored for the varying histologies. Taken together, these data suggest that expression profiling can be used diagnostically to distinguish individual histologic subclassifications and may guide the selection of target therapeutics. [Copyright &y& Elsevier]

Purpose: To investigate the value of performing mid-treatment axillary ultrasound (AUS) in triple-negative breast cancer (TNBC) patients who are undergoing neoadjuvant systemic therapy (NAST) by determining the optimal cutoff number of abnormal nodes associated with residual nodal disease on surgical pathology.Materials and Methods: This sub-study, an interim analysis of an ongoing single-institution clinical trial enrolling patients with stage I-III TNBC, included 106 patients. Number of abnormal nodes at mid-treatment was assessed and recorded by experienced breast radiologists, who empirically categorized lymph nodes using a binary approach of sonographically-normal versus abnormal. Pathologic lymph node positivity was defined as presence of macrometastasis or micrometastasis in ≥1 axillary node from sentinel lymph node biopsy and/or axillary lymph node dissection.Results: Of 106 patients, 26 (25 %) had residual nodal disease and 80 (75 %) had no nodal disease at surgery. Median number of abnormal nodes at mid-treatment was 5 (standard deviation [SD], 5) for patients with residual nodal disease and 0 (SD, 2) for patients with no nodal disease at surgery (p < 0.0001). TNBC patients with >4 abnormal nodes at mid-treatment had a significantly higher chance of being node-positive at surgery (AUC = 0.908, p < 0.0001; PPV = 90 %).Conclusion: Our data suggest that a cutoff of >4 abnormal nodes on mid-treatment AUS is associated with residual disease post-NAST. If our findings are substantiated by subsequent analyses, then mid-treatment AUS could be used to identify patients unlikely to achieve nodal pathologic complete response and who should be offered alternative therapy. [ABSTRACT FROM AUTHOR]