Olanzapine With or Without Fosaprepitant for Preventing Chemotherapy Induced Nausea and Vomiting in Patients Receiving Highly Emetogenic Chemotherapy: A Phase III Randomized, Double-Blind, Placebo-Controlled Trial (ALLIANCE A221602).

PURPOSE: A protocol was developed to evaluate the value of an NK-1 receptor antagonist for preventing nausea and vomiting resulting from highly emetogenic chemotherapy when an olanzapine-based antiemetogenic regimen was used. MATERIALS AND METHODS: A221602, a prospective double-blind, placebo-controlled clinical trial, was developed to compare 2 -olanzapine-containing antiemetic regimens, one with an NK-1 receptor antagonist (aprepitant or fosaprepitant) and one without. Trial patients had a malignant disease for which they received intravenous highly emetogenic chemotherapy (single day cisplatin ≥ 70 mg/m2 or doxorubicin plus cyclophosphamide on 1 day). Patients on both arms received commonly administered doses of a 5-HT3 receptor antagonist, dexamethasone, and olanzapine. Additionally, patients were randomized to receive an NK-1 receptor antagonist (fosaprepitant 150 mg IV or aprepitant 130 mg IV) or a corresponding placebo. The primary objective was to compare the proportion of patients with no nausea for 5 days following chemotherapy between the 2 study arms. This trial was designed to test for the noninferiority of deleting the NK-1 receptor antagonist, with noninferiority defined as a decrease in freedom from nausea by less than 10%. RESULTS: A total of 690 patients were entered on this trial, 50% on each arm. The proportion of patients without nausea for the complete 5-day study period was 7.4% lower (upper limit of the one-sided 95% confidence interval was 13.5%) in the arm without an NK-1 receptor antagonist compared with the arm with an NK-1 receptor antagonist. CONCLUSION: This trial did not provide sufficient evidence to support that deletion of the NK-1 receptor antagonist was as good as keeping it, as a part of a 4-drug antiemetic regimen for highly emetogenic chemotherapy (ClinicalTrials.gov Identifier: NCT03578081).

Randomized Phase II Trial of Endocrine Therapy With or Without Ribociclib After Progression on Cyclin-Dependent Kinase 4/6 Inhibition in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Metastatic Breast Cancer: MAINTAIN Trial.

PURPOSE: Cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) with endocrine therapy (ET) improves progression-free survival (PFS) and overall survival (OS) in hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC). Although preclinical and clinical data demonstrate a benefit in changing ET and continuing a CDK4/6i at progression, no randomized prospective trials have evaluated this approach. METHODS: In this investigator-initiated, phase II, double-blind placebo-controlled trial in patients with HR+/HER2- MBC whose cancer progressed during ET and CDK4/6i, participants switched ET (fulvestrant or exemestane) from ET used pre-random assignment and randomly assigned 1:1 to the CDK4/6i ribociclib versus placebo. PFS was the primary end point, defined as time from random assignment to disease progression or death. Assuming a median PFS of 3.8 months with placebo, we had 80% power to detect a hazard ratio (HR) of 0.58 (corresponding to a median PFS of at least 6.5 months with ribociclib) with 120 patients randomly assigned using a one-sided log-rank test and significance level set at 2.5%. RESULTS: Of the 119 randomly assigned participants, 103 (86.5%) previously received palbociclib and 14 participants received ribociclib (11.7%). There was a statistically significant PFS improvement for patients randomly assigned to switched ET plus ribociclib (median, 5.29 months; 95% CI, 3.02 to 8.12 months) versus switched ET plus placebo (median, 2.76 months; 95% CI, 2.66 to 3.25 months) HR, 0.57 (95% CI, 0.39 to 0.85); P = .006. At 6 and 12 months, the PFS rate was 41.2% and 24.6% with ribociclib, respectively, compared with 23.9% and 7.4% with placebo. CONCLUSION: In this randomized trial, there was a significant PFS benefit for patients with HR+/HER2- MBC who switched ET and received ribociclib compared with placebo after previous CDK4/6i and different ET.

School allergy training promotes internal policy review and enhances staff's preparedness in managing pupils with food allergy.

BACKGROUND: Recently non-statutory allergy management guidance for schools has been produced in the United Kingdom; however, there has been limited progress in implementing this. The aim of this study was to evaluate the effect of face-to-face training on self-reported school staff preparedness in managing the severely allergic child and whether it would stimulate schools' allergy policy review. METHODS: A preparedness survey was conducted prior and 2 months post-intervention to assess the effect of training on self-reported preparedness and perceived confidence to manage children with food allergies. RESULTS: A sample of 18 primary schools that consented to participate were selected. Of the trained schools, 89% of the head teachers felt confident in dealing with an allergy emergency compared to 39% prior training (p = 0.016). Post-intervention all but one had arranged/were considering introducing allergy awareness sessions to help pupils manage their allergies (45% pre-training vs. post-training 93%, p = 0.003). Preventative measures for accidental exposure to food allergens (i.e., no food sharing policy) were adopted by all (pre-training 61% vs. post-training 100%, p = 0.03). CONCLUSION: A face-to-face school allergy training programme enhances self-reported staff preparedness and promotes internal allergy policy review in managing the needs of these children, hence addressing the current gap between recommendations and practice in schools.

Treatment with Granulocyte-colony Stimulating Factor (G-CSF) is not associated with Increased Risk of Brain Metastasis in Patients with De Novo Stage IV Breast Cancer.

Background: Survival outcome after developing brain metastasis is poor and there is an unmet need to identify factors that can promote brain metastasis. Granulocyte-colony stimulating factor (G-CSF) is given to support neutrophil recovery after myelosuppressive chemotherapy to some patients. However, there is emerging evidence that neutrophils can promote metastasis, including through the formation of neutrophil extracellular traps (NETs), scaffolds of chromatin with enzymes expelled from neutrophils to the extracellular space. In animal models, G-CSFs can induce NETs to promote liver and lung metastasis. The primary objective of this study was to test the association between G-CSF use and the later incidence of brain metastasis. Methods: Patients with de novo Stage IV breast cancer, without known brain metastasis at the time of initial diagnosis, were identified from electronic medical records covering the period from 1/1/2013 to 12/31/2020 at Northwell Health. Univariate and multivariate logistic regression models were used to test the association between variables of interest, including G-CSF use, and brain metastasis. Results: A total of 78 patients were included in the final analysis. Among those 78 patients, 24 patients (30.8%) had received G-CSF along with chemotherapy at least once. In logistic regression models, G-CSF use was not a significant factor to predict brain metastasis (OR 1.89 [95%CI 1.89-5.33]; P=0.23). Interestingly, in multivariate logistic models, pulmonary embolism (PE)/deep venous thrombosis (DVT) was a significant predictive factor of brain metastasis (OR 6.74 [95%CI 1.82-25.01]; P=0.004) (38.5% vs 21.5%). Conclusions: The use of G-CSF was not associated with increased risk of brain metastasis in patients with de novo Stage IV breast cancer. Interestingly, PE/DVT, which can be associated with elevated NETs, was associated with brain metastasis. Further studies are warranted to determine whether DVT/PE with or without elevated NETs levels in the blood, is predictive of developing brain metastasis in patients with de novo Stage IV breast cancer.

A survey of school's preparedness for managing anaphylaxis in pupils with food allergy.

Allergic diseases are on the increase and can affect the child's well-being. The aim of this survey was to assess regional schools' preparedness in dealing with anaphylaxis following the publication of national and international guidelines for schools in 2014. The survey was developed in 2015 and distributed to schools in Cumbria, North West England, UK between 2015 and 2016. Only 47% of the respondents (95% CI, 39-57%) felt confident to manage anaphylaxis. Schools without allergic pupils were significantly less likely to have a standard management protocol in place for emergencies compared to those with allergic pupils (p < 0.001). The majority of the schools indicated that further training was needed (81% (95% CI, 74-88%).Conclusion: At the time of the survey, schools' preparedness in the region, did not meet safety standards recommended by national and international organisations. Although schools have shown eagerness in accessing training in the management of anaphylaxis, tailored training for schools is not yet widely available. There is now an urgent need to design feasible training strategies that create a safe environment for allergic pupils across all UK schools. What is Known: • One quarter of the severe allergic reactions take place for the first time while at school with some of them being fatal. • School staff is ill-prepared in the management of anaphylaxis. Access to formal training is not widely available. What is New: • School staff remains unconfident in managing the severe allergic child. Training in the management of anaphylaxis is scarce, and when available, it does not offer the required depth to cover the holistic needs of allergic pupils. • Schools would welcome generic adrenaline autoinjectors and a national policy with central funding which would describe step by step the necessary measures for the management of anaphylaxis.

Randomized phase II trial of fulvestrant alone or in combination with bortezomib in hormone receptor-positive metastatic breast cancer resistant to aromatase inhibitors: a New York Cancer Consortium trial.

The proteasome inhibitor bortezomib enhances the effect of the selective estrogen receptor (ER) downregulator (SERD) fulvestrant by causing accumulation of cytoplasmic ER aggregates in preclinical models. The purpose of this trial was to determine whether bortezomib enhanced the effectiveness of fulvestrant. One hundred eighteen postmenopausal women with ER-positive metastatic breast cancer resistant to aromatase inhibitors (AIs) were randomized to fulvestrant alone (Arm A-500 mg intramuscular (i.m.) day -14, 1, 15 in cycle 1, and day 1 of additional cycles) or in combination with bortezomib (Arm B-1.6 mg/m2 intravenous (i.v.) on days 1, 8, 15 of each cycle). The study was powered to show an improvement in median progression-free survival (PFS) from 5.4 to 9.0 months and compare PFS rates at 6 and 12 months (α=0.10, ß=0.10). Patients with progression on fulvestrant could cross over to the combination (arm C). Although there was no difference in median PFS (2.7 months in both arms), the hazard ratio for PFS in Arm B versus Arm A (referent) was 0.73 (95% confidence interval (CI)=0.49, 1.09, P=0.06, 1-sided log-rank test, significant at the prespecified 1-sided 0.10 α level). At 12 months, the PFS proportion in Arm A and Arm B was 13.6% and 28.1% (P=0.03, 1-sided χ2-test; 95% CI for difference (14.5%)=-0.06, 29.1%). Of 27 patients on arm A who crossed over to the combination (arm C), 5 (18%) were progression-free for at least 24 weeks. Bortezomib likely enhances the effectiveness of fulvestrant in AI-resistant, ER-positive metastatic breast cancer by reducing acquired resistance, supporting additional evaluation of proteasome inhibitors in combination with SERDs.

Phase I-II study of the farnesyl transferase inhibitor tipifarnib plus sequential weekly paclitaxel and doxorubicin-cyclophosphamide in HER2/neu-negative inflammatory carcinoma and non-inflammatory estrogen receptor-positive breast carcinoma.

Tipifarnib (T) is a farnesyl transferase inhibitor (FTI) that enhances the antineoplastic effects of cytotoxic therapy in vitro, has activity in metastatic breast cancer, and enhances the pathologic complete response (pCR) rate to neoadjuvant doxorubicin-cyclophosphamide (AC) chemotherapy. We, therefore, performed a phase I-II trial of T plus neoadjuvant sequential weekly paclitaxel and 2-week AC chemotherapy in locally advanced breast cancer. Eligible patients with HER2-negative clinical stage IIB-IIIC breast cancer received 12 weekly doses of paclitaxel (80 mg/m(2)) followed by AC (60/600 mg/m(2) every 2 weeks and filgrastim), plus T (100 or 200 mg PO on days 1-3 of each P dose, and 200 mg PO on days 2-7 of each AC cycle). The trial was powered to detect an improvement in breast pCR rate from 15 to 35 % (α = 0.10, ß = 0.10) in two strata, including ER and/or PR-positive, non-inflammatory (stratum A) and inflammatory carcinoma (stratum B). Of the 60 patients accrued, there were no dose-limiting toxicities among the first six patients treated at the first T dose level (100 mg BID; N = 3) or second T dose level (200 mg BID; N = 3) plus paclitaxel. Breast pCR occurred in 6/33 patients (18 %, 95 % confidence intervals (CI) 7-36 %) and 1/22 patients (4 %, 95 % CI 0-8 %) in stratum B. Combination of the FTI T with weekly paclitaxel-AC is unlikely to be associated with a breast pCR rate of 35 % or higher in patients with locally advanced HER2/neu-negative inflammatory or non-inflammatory ER- and/or PR-positive breast carcinoma.

Cord blood leptin levels of healthy neonates are associated with IFN-γ production by cord blood T-cells.

Leptin is a hormone synthesized by adipocytes and other tissues, including the placenta, and it regulates food intake and energy expenditure, reproductive and immune functions. To investigate the role of leptin in neonatal immunity, we measured serum leptin and cytokine (IFN-γ, TNF-α, IL-2, IL-4, IL-10, IL-12) levels in the cord blood (cb) of 510 healthy neonates, 14 small for gestational age (SGA), 312 appropriately grown for gestational age (AGA) and 184 large for gestational age (LGA). Median serum leptin concentration in the whole sample was 11 ng/ml. In 11.2% neonates (1 SGA, 32 AGA, 24 LGA), leptin levels were >90th percentile (median 39 ng/ml). In 33.3% of those (3.72% of total sample) with the highest leptin levels (median 46 ng/ml), significantly elevated levels of serum IFN-γ were also found (mean 27.11 pg/ml, range 17.5-38.5 pg/ml). In neonates with leptin levels ∼50th percentile (median 12 ng/ml) or <10th percentile (median 1 ng/ml), serum IFN-γ levels were negligible. All other cytokines measured, were < the assays' detection limits. To investigate whether leptin can independently influence cytokine gene expression by cb T-cells and monocytes (Mc), we cultured cb T-cells or Mc, isolated from randomly selected AGA neonates or adult peripheral blood, with leptin. This resulted in upregulation of IL-2, IFN-γ and IL-4 gene expression in cb and adult T-cells and IL-10 expression mainly in cb-Mc. Significantly higher expression of IFN-γ occurred in female cb-T-cells cultured with leptin, compared with male cb-T-cells. In conclusion, the concurrent presence of high concentrations in both leptin and IFN-γ in cb of healthy infants, and leptin's ability to directly upregulate cytokine gene expression in cb T and Mc cells, indicate that abnormally high leptin levels can independently influence the immune system of healthy newborns, and may mediate gender differences in the development of a Th1 polarized immune response.

Hormonal modulation in the treatment of breast cancer.

This article explores the history of endocrine therapy for the treatment of breast cancer, the clinical evidence behind the current standards of care, and controversies that may change these standards in the future.

Tamoxifen metabolite isomer separation and quantification by liquid chromatography-tandem mass spectrometry.

Tamoxifen (Tam), the antiestrogen used to treat estrogen receptor-positive breast cancer is a pro-drug that is converted to its major active metabolites, endoxifen and 4-hydroxy-tamoxifen (4-OH-Tam) by various biotransformation enzymes of which cytochrome P450-2D6 (CYP2D6) is key. The usual Tam dose is 20 mg daily; however, the plasma active metabolite concentrations vary due to common genetic variants encoding the biotransformation enzymes and environmental factors (e.g., concomitant drugs) that inhibit these enzymes. Effective treatment depends on adequate Tam conversion to its active isomers. To monitor metabolite plasma levels, a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to separate and quantitate Tam, N-desmethyl-tamoxifen (ND-Tam), and tamoxifen-N-oxide (Tam-N-oxide), and the E, Z, and Z' isomers of endoxifen and 4-OH-Tam. Known standards were used to identify each metabolite/isomer. Quantitation of these metabolites in plasma was linear from 0.6 to 2000 nM. Intra- and inter-assay reproducibilities were 0.2-8.4% and 0.6-6.3%, respectively. Accuracy determined by spike experiments with known standards was 86-103%. Endoxifen, 4-OH-Tam, and their isomers were stable in fresh frozen plasma for ≥6 months. This method provides the first sensitive, specific, accurate, and reproducible quantitation of Tam and its metabolite isomers for monitoring Tam-treated breast cancer patients.

Highlights of the Chemotherapy Foundation Symposium XXVII: therapeutic options for breast cancer.

The XXVII Annual Chemotherapy Foundation Symposium sponsored by The Mount Sinai School of Medicine is one of the leading forums for communication of important discoveries and new developments in cancer therapeutics. Here, we summarize and review the emerging advances in the treatment of breast cancer, which includes therapeutics in HER signaling, poly(ADP-ribose) polymerase inhibition, PI3K inhibitors and novel epithilones.

Conducting Molecular Epidemiological Research in the Age of HIPAA: A Multi-Institutional Case-Control Study of Breast Cancer in African-American and European-American Women.

Breast cancer in African-American (AA) women occurs at an earlier age than in European-American (EA) women and is more likely to have aggressive features associated with poorer prognosis, such as high-grade and negative estrogen receptor (ER) status. The mechanisms underlying these differences are unknown. To address this, we conducted a case-control study to evaluate risk factors for high-grade ER- disease in both AA and EA women. With the onset of the Health Insurance Portability and Accountability Act of 1996, creative measures were needed to adapt case ascertainment and contact procedures to this new environment of patient privacy. In this paper, we report on our approach to establishing a multicenter study of breast cancer in New York and New Jersey, provide preliminary distributions of demographic and pathologic characteristics among case and control participants by race, and contrast participation rates by approaches to case ascertainment, with discussion of strengths and weaknesses.

Effect of pretreatment distress on daily fatigue after chemotherapy for breast cancer.

PURPOSE: Fatigue is one of the most frequently reported and adverse effects of cancer chemotherapy. The present study tested the hypothesis that women's levels of emotional distress at the time of their initial outpatient chemotherapy treatment would predict the severity of their postinfusion fatigue. METHODS: Sixty stage I (32.6%) and II (67.4%) patients with breast cancer (mean age, 44.5 years) who were receiving standard outpatient chemotherapy participated. The independent variable, emotional distress, was assessed for "last night," "this morning," and "right now" with a visual analog scale (0 to 100). The dependent variable, post-treatment fatigue (PTF), was assessed (0 to 100) over each of the subsequent 6 days using end-of-day diaries, which also included assessments of distress and nausea (0 to 100). For the statistical analyses, post-treatment fatigue was divided into three phases with means calculated for days 1 through 2 (phase 1), 3 to 4 (phase 2), and 5 to 6 (phase 3). RESULTS: Consistent with the study hypothesis, patients' pretreatment distress level in the clinic was a significant (P < .001) predictor of PTF. There was also a significant (P < .025) interaction with phase, with distress becoming a predictor of PTF after phase 1. Multivariate analysis indicated that prior levels of distress were not independent predictors of PTF. CONCLUSIONS: This study is the first to demonstrate time-specific effects of pretreatment distress on PTF. Possible mechanisms of these effects now warrant investigation, as do possible benefits of brief interventions to reduce patient distress immediately before treatment.

Prevalence of joint symptoms in postmenopausal women taking aromatase inhibitors for early-stage breast cancer.

PURPOSE: Aromatase inhibitors (AIs) improve survival in postmenopausal women with hormone-sensitive breast cancer, but can cause joint pain and stiffness. The purpose of the current study was to evaluate the prevalence of and identify risk factors for AI-related joint symptoms. PATIENTS AND METHODS: We performed a cross-sectional survey of consecutive postmenopausal women receiving adjuvant AI therapy for early-stage hormone-sensitive breast cancer at an urban academic breast oncology clinic. Patients completed a 25-item self-administered questionnaire assessing the presence of joint symptoms that started or worsened after initiating AIs. Multivariate regression was used to compare those with AI-related arthralgia with those who did not report symptoms, adjusting for demographic and clinical factors. RESULTS: Of 200 patients who completed the survey, 94 (47%) reported having AI-related joint pain and 88 (44%) reported AI-related joint stiffness. In multiple logistic regression analysis, being overweight (body mass index of 25 to 30 kg/m(2)) and prior tamoxifen therapy were inversely associated with AI-related joint symptoms. Patients who received taxane chemotherapy were more than four times more likely than other patients to have AI-related joint pain and stiffness (odds ratio [OR] = 4.08, 95% CI, 1.58 to 10.57 and OR = 4.76; 95% CI, 1.84 to 12.28, respectively). CONCLUSION: Our study suggests that AI-related joint symptoms are more prevalent than what has been described previously in clinical trials. The success of AI therapy depends on patients' ability to adhere to treatment recommendations; therefore, additional studies of interventions that may alleviate these symptoms are needed.

Racial disparities in treatment and survival of male breast cancer.

PURPOSE: Black women with breast cancer have poorer survival than do white women, but little is known about racial disparities in male breast cancer. We analyzed race and other predictors of treatment and survival among men with stage I-III breast cancer. PATIENTS AND METHODS: We used the Surveillance, Epidemiology, and End Results (SEER) Medicare database to identify men 65 years of age or older diagnosed with stage I-III breast cancer from 1991 to 2002. Multivariate regression was used to compare those treated with those not treated with either chemotherapy or radiation therapy, adjusting for known clinical and demographic factors. Cox proportional hazards regression models were used to analyze survival. RESULTS: Of 510 male breast cancer cases (456 white, 34 black), 94% underwent mastectomy, 28% received adjuvant chemotherapy, and 29% received radiation therapy. Among those with known hormone receptors, 95% had hormone-sensitive tumors. In a multivariate analysis, chemotherapy was associated with younger age, advanced stage, and hormone receptor-negative tumors. Radiation therapy was associated with younger age and advanced stage. Black men were approximately 50% less likely to undergo consultation with an oncologist and subsequently receive chemotherapy; however, the results did not reach statistical significance. The breast cancer-specific mortality hazard ratio was more than tripled for black versus white men (hazard ratio = 3.29; 95% CI, 1.10 to 9.86). CONCLUSION: After adjustment for known clinical, demographic, and treatment factors, there was an association of black race with increased male breast cancer-specific mortality. Although male breast cancer is rare, the reasons for these disparities need to be better understood.

Pilot study of acupuncture for the treatment of joint symptoms related to adjuvant aromatase inhibitor therapy in postmenopausal breast cancer patients.

INTRODUCTION: Aromatase inhibitors (AIs) have become the standard of care for the adjuvant treatment of postmenopausal, hormone-sensitive breast cancer. However, patients receiving AIs may experience joint symptoms, which may lead to early discontinuation of this effective therapy. We hypothesize that acupuncture is a safe and effective treatment for AI-induced arthralgias. METHODS: Postmenopausal women with early-stage breast cancer who had self-reported musculoskeletal pain related to adjuvant AI therapy were randomized in a crossover study to receive acupuncture twice weekly for 6 weeks followed by observation or vice-versa. The intervention included full body and auricular acupuncture, and a joint-specific point prescription. Outcome measures included the Brief Pain Inventory-Short Form (BPI-SF), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index, the Functional Assessment of Cancer Therapy-General (FACT-G) quality of life measure, and serum levels of inflammatory markers, IL-1 beta and TNF-alpha. RESULTS: Twenty-one women were enrolled and two discontinued early. From baseline to the end of treatment, patients reported improvement in the mean BPI-SF worst pain scores (5.3 to 3.3, p = 0.01), pain severity (3.7 to 2.5, p = 0.02), and pain-related functional interference (3.1 to 1.7, p = 0.02), as well as the WOMAC function subscale and FACT-G physical well-being (p = 0.02 and 0.04, respectively). No adverse events were reported. DISCUSSION/CONCLUSIONS: In this pilot study, acupuncture reduced AI-related joint symptoms and improved functional ability and was well-tolerated. IMPLICATIONS FOR CANCER SURVIVORS: Musculoskeletal side effects are common among breast cancer survivors on adjuvant AI therapy, therefore, effective treatments are needed for symptom relief and to improve adherence to these life-saving medications.

Identification of mammaglobin as a novel serum marker for breast cancer.

PURPOSE: Early detection of breast cancer has implications for the management and treatment of patients with this disease. Currently, there exist no highly sensitive and specific serologic biomarkers for detection of breast cancer. Mammaglobin is predicted to be a secreted protein, and expression of this gene seems to be highly specific in breast cancer. The present studies were undertaken to develop the mammaglobin protein as a serum biomarker for detection of breast cancer. EXPERIMENTAL DESIGN: We characterized the mammaglobin protein as a secreted, 14- to 21-kDa species, which is likely post-translationally processed based on its predicted 7-kDa size. Immunostaining for mammaglobin was conducted. An ELISA was developed for the detection of the mammaglobin protein in serum, and levels were compared between women with and without breast cancer. A receiver operating characteristic curve was used to show sensitivity and specificity for cut points on the continuous mammaglobin scale. RESULTS: The protein was detectable by immunostaining in 72% of breast tumors and not in other tumor types. The ELISA was highly sensitive and specific for detection of mammaglobin protein in tissue culture fluids of breast cancer cells and sera of breast cancer patients. The ELISA differentiated healthy women from those with breast cancer with accurate, repeatable results across time and under varying storage conditions. CONCLUSION: Our results indicate that mammaglobin, as measured by the ELISA, holds significant promise for breast cancer screening with the realistic potential to impact management of this disease.