Local production of lactate, ribose phosphate, and amino acids within human triple-negative breast cancer.

BACKGROUND: Upregulated glucose metabolism is a common feature of tumors. Glucose can be broken down by either glycolysis or the oxidative pentose phosphate pathway (oxPPP). The relative usage within tumors of these catabolic pathways remains unclear. Similarly, the extent to which tumors make biomass precursors from glucose, versus take them up from the circulation, is incompletely defined. METHODS: We explore human triple negative breast cancer (TNBC) metabolism by isotope tracing with [1,2-13C]glucose, a tracer that differentiates glycolytic versus oxPPP catabolism and reveals glucose-driven anabolism. Patients enrolled in clinical trial NCT03457779 and received IV infusion of [1,2-13C]glucose during core biopsy of their primary TNBC. Tumor samples were analyzed for metabolite labeling by liquid chromatography-mass spectrometry (LC-MS). Genomic and proteomic analyses were performed and related to observed metabolic fluxes. FINDINGS: TNBC ferments glucose to lactate, with glycolysis dominant over the oxPPP. Most ribose phosphate is nevertheless produced by oxPPP. Glucose also feeds amino acid synthesis, including of serine, glycine, aspartate, glutamate, proline and glutamine (but not asparagine). Downstream in glycolysis, tumor pyruvate and lactate labeling exceeds that found in serum, indicating that lactate exchange via monocarboxylic transporters is less prevalent in human TNBC compared with most normal tissues or non-small cell lung cancer. CONCLUSIONS: Glucose directly feeds ribose phosphate, amino acid synthesis, lactate, and the TCA cycle locally within human breast tumors.

Association of Low Nodal Positivity Rate Among Patients With ERBB2-Positive or Triple-Negative Breast Cancer and Breast Pathologic Complete Response to Neoadjuvant Chemotherapy.

Importance: A recent publication reported that of 527 patients with clinically node-negative (cN0) cT1/cT2 triple-negative breast cancer (TNBC) or ERBB2-positive disease treated with neoadjuvant chemotherapy (NAC), 100% of those who achieved a breast pathologic complete response (pCR) had pathologic node negativity (pN0). Eliminating axillary surgery in these patients has been suggested as safe based on these results. Objective: To evaluate nodal positivity rates in patients with cT1/cT2 N0 ERBB2-positive disease and TNBC with a breast pCR after NAC using the National Cancer Database (NCDB), which included academic and community settings. Design, Setting, and Participants: This retrospective study reviewed data from the NCDB from January 1, 2010, through December 31, 2015. Participants included patients with cN0/cN1 cT1/cT2 breast cancer who received NAC followed by surgery. Pathologic nodal positivity rates by breast pCR were compared in cN0 and cN1 disease, within each tumor subtype (ERBB2-positive, TNBC, and hormone receptor-positive/ERBB2-negative). Data were analyzed from September 13, 2017, through January 30, 2018. Exposures: Neoadjuvant chemotherapy followed by surgery. Main Outcomes and Measures: The pathologic nodal positivity rate after NAC (ypN) specifically in patients with cT1/cT2 cN0 ERBB2-positive disease or TNBC who achieve a breast pCR after NAC. Results: A total of 30 821 patients with cT1/cT2 cN0/cN1 breast cancer treated with NAC and surgical resection (99.6% female; mean [SD] age, 52.0 [11.5] years) were identified. Of 6802 patients with cN0 ERBB2-positive disease, 3062 (45.0%) achieved breast pCR and of those, 49 (1.6%; 95% CI, 1.2%-2.1%) were ypN positive. In 6222 patients with cN0 TNBC, 2315 (37.2%) achieved breast pCR, and of those, 36 (1.6%; 95% CI, 1.1%-2.1%) were pathologic node positive after NAC. Rates of ypN positivity were higher in patients with cN0 and residual disease in the breast; 632 of 3740 (16.9%) with ERBB2-positive disease and 492 of 3907 (12.6%) with TNBC with residual disease in the breast were node positive (P < .001). Among 4164 patients with cN1 ERBB2-positive disease, 1801 (43.3%) achieved breast pCR, with 223 of those (12.4%) being ypN positive. In 3293 patients with TNBC, 1229 (37.3%) achieved breast pCR, with 173 of these (14.1%) being ypN postive. Breast pCR rates were lower in hormone receptor-positive/ERBB2-negative disease (646 of 5069 [12.7%] for cN0; 711 of 5271 [13.5%] for cN1) and ypN positivity rates were 26 of 646 (4.0%) in cN0 vs 217 of 711 (30.5%) in cN1 disease with breast pCR and 1464 of 4423 (33.1%) in cN0 disease vs 3775 of 4560 (82.8%) in cN1 disease with residual disease in the breast. Conclusions and Relevance: In this study, the highest rates of breast pCR were seen in ERBB2-positive disease and TNBC. In patients with cN0 ERBB2-positive disease or TNBC with breast pCR, the nodal positivity rate was less than 2%, which supports consideration of omission of axillary surgery in this subset of patients.

Predicting Non-sentinel Lymph Node Metastases in Patients with a Positive Sentinel Lymph Node After Neoadjuvant Chemotherapy.

BACKGROUND: The standard of care for breast cancer patients treated with neoadjuvant chemotherapy (NAC) who have a positive sentinel lymph node (+SLN) after NAC is completion axillary lymph node dissection (ALND). This study aimed to develop a nomogram to predict additional nodal disease in patients with +SLN after NAC. METHODS: The study reviewed patients 18 years of age or older who had invasive breast cancer treated with NAC followed by SLN surgery with +SLN and ALND between 2006 and 2017 at the authors' institution. Factors predictive of positive non-SLNs were analyzed using uni- and multivariable logistic regression. RESULTS: The study identified 120 patients with +SLN after NAC and ALND. Of these patients, 30.8% were clinically node-negative (cN-), and 69.2% were clinically node-positive (cN+) before NAC. Tumor biology was human epidermal growth factor receptor 2-positive (HER2+) for 20%, hormone receptor-positive (HR+)/HER2- for 66.7%, and triple-negative breast cancer (TNBC) for 13.3% of the patients. Additional nodal disease was found on ALND for 63.3% of the patients. In the univariate analysis, the factors predictive of positive non-SLNs were biologic subtype (TNBC and HR+/HER2- vs HER2+; p < 0.001), higher grade (p = 0.047), higher pT category (p = 0.02), SLN extranodal extension (p = 0.03), larger SLN metastasis size (p < 0.001), and higher number of +SLNs (p = 0.02). The factors significant in the multivariable analysis included number of +SLNs, grade 3 vs grade 1 or 2, HER2+ versus HER2-, cN+ versus cN-, and larger SLN metastasis size. The resulting model showed excellent discrimination (area under the curve, 0.82; 95% confidence interval, 0.74-0.90) and good calibration (p = 0.54, Hosmer-Lemeshow). CONCLUSION: A clinical prediction model incorporating biologic subtype, grade, clinical node status, size of the largest SLN metastasis, and number of +SLNs can help physicians and patients estimate the likelihood of additional nodal disease and may be useful for guiding decision making regarding axillary management.

Bracketed radioactive seed localization vs bracketed wire-localization in breast surgery.

Multiple localizers placed in a bracketed fashion facilitates excision of radiographically extensive breast lesions. In this study, bracketed radioactive seed localization (bRSL) was compared to bracketed wire localization (bWL). We hypothesized that bRSL would achieve adequate margins and decrease re-operation rates with similar or less specimen volumes (SV) than bWL. Retrospective review identified patients who underwent bracketed breast procedures at an academic medical center. Data collected included patient demographics, tumor features, treatment variables, and surgical outcomes. Wilcoxon rank-sum test and chi-square test were used to compare continuous and categorical data, respectively. A multivariable logistic regression model was used to evaluate the association between re-excision and localization technique after adjusting for clinically relevant variables. Patients who underwent bWL were 3.9 times more likely to undergo re-excision compared to patients in bRSL group (OR=3.9, 95% CI: 2.0-7.4). Initial and total SV did not significantly differ between the two groups (P=.4). Patients were significantly more likely to undergo a mastectomy in the bWL group than in the bRSL group (24% vs 7%; P<.01). For patients undergoing excision of radiologically extensive breast lesions, bRSL serves as an alternative to bWL. In this retrospective study, bRSL was associated with a decreased re-excision rate with similar SV and a lower rate of mastectomy when compared to bWL.

Do acute-care surgeons follow best practices for breast abscess management? A single-institution analysis of 325 consecutive cases.

BACKGROUND: The breast surgery community has adopted needle aspiration as the standard of care for breast abscesses, which have a size less than 5 cm on ultrasound, no skin changes, and fewer than 5 days of symptoms. Our acute-care surgery (ACS) service manages all breast abscess consults at our urban safety-net hospital. We undertook this descriptive study to identify the rate of operative incisions and drainage performed by ACS surgeons which were not compatible with best practices for breast abscess management. METHODS: We performed a retrospective review of the electronic health records of all patients on whom the ACS service was consulted for a breast abscess at our urban safety-net hospital between January 2010 and December 2014. We collected data on patient demographics, breast skin characteristics, length of symptoms, ultrasound results, and treatment modality. RESULTS: A total of 325 patients with breast abscesses were evaluated by ACS, of whom 21 met the breast community's indications for needle aspiration. Of the overall 325 subject sample, 281 (86.5%) underwent incision and drainage (I&D), and 44 (13.5%) underwent bedside needle aspiration. Of the 281 patients that underwent I&D, 269 (95.7%) met the breast surgery community's indications for I&D due to either skin changes (n = 90, 33.5%), abscess >5 cm on ultrasound (n = 88, 32.7%), or symptoms >5 days (n = 238, 88.5%). Of the 44 patients that underwent needle aspiration, only 9 (20.5%) met the current practice indications for aspiration. Of the 44 patients that underwent aspiration, 28 (63.6%) failed and went on to have an operation. The majority of these failed aspirations had symptoms >5 days (23 patients, 82.1%) or had skin changes at presentation (1 patient, 3.6%) or an abscess >5 cm on ultrasound (5 patients, 17.9%). CONCLUSIONS: As judged by best practices promulgated by the breast surgery community, ACS surgeons do not show excessive rates of operative I&D of breast abscess and in fact seem to overutilize needle aspiration. To our knowledge, this is the largest single institution series of the management of breast abscesses by ACS surgeons in the literature.