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BACKGROUND AND PURPOSE: The cost of illness in cancer care and the subsequent distress has attracted scrutiny. Guidelines recommend enhanced discussion of costs, assuming this will reduce both stress and costs. Little is known about patient attitudes about cost considerations influencing treatment decisions. METHODS: A convenience-sample survey of patients currently receiving radiation and/or intravenous chemotherapy at an outpatient cancer center was performed. Assessments included prevalence and extent of financial burden, level of financial distress, attitudes about using costs to influence treatment decisions, and frequency or desirability of cost discussions with oncologists. RESULTS: A total of 132 participants (94%) responded. Overall, 47% reported high financial stress, 30.8% felt well informed about costs prior to treatment, and 71% rarely spoke to their oncologists about cost. More than 71% of patients did not want either society's or personal costs to influence treatment, and this result did not change based on degree of financial stress. Even when asked to assume that lower cost regimens were equally effective, only 28% would definitely want the lower cost regimen. Patients did not believe it was the oncologist's duty to perform cost discussions. CONCLUSION: Even insured patients have a high degree of financial distress. Most, including those with the highest levels of distress, did not speak often with oncologists about costs and were strongly adverse to having cost considerations influence choice of regimen. The findings suggest that patients are not cost sensitive with regard to treatment decisions. Oncologists will require improved tools to have meaningful cost discussion, as recommended by the American Society of Clinical Oncology.
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Costo de Enfermedad , Neoplasias/economía , Adulto , Anciano , Anciano de 80 o más Años , Actitud Frente a la Salud , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Prioridad del Paciente , Relaciones Médico-Paciente , Adulto JovenRESUMEN
BACKGROUND: Serum and plasma levels of vascular endothelial growth factor (VEGF) correlate with prognosis in patients with metastatic breast cancer (MBC). VEGF binds to 2 receptors on endothelial cells, VEGFR-1 and VEGFR-2. RPI.4610 (Angiozyme0) is an antiangiogenic ribozyme targeting the VEGFR-1 mRNA. Preclinical and phase 1 studies suggested that RPI.4610 is a well-tolerated agent with clinical activity in solid tumors. The authors' trial evaluated the efficacy of RPI.4610 in the treatment of patients with progressive MBC. METHODS: This phase 2, multicenter, single-arm study was designed to assess the objective response rate of RPI.4610 in patients with MBC who had experienced disease progression with at least 1 course of chemotherapy for MBC. Patients received daily subcutaneous injections of RPI.4610 100 mg/m(2) for 12 weeks. RESULTS: Most patients (93%) had received at least 2 lines of chemotherapy previously; 69% of patients had received at least 3 lines of chemotherapy. Median follow-up was 2.76 months (range, 0.89-36.6 months). No partial responses nor complete responses were found. Median progression-free survival was 1.41 months (95% confidence interval [CI], 1.35-1.45). The median overall survival from start of treatment was 11.89 months (95% CI, 4.11-23.66). Treatment-related adverse events (AEs) were primarily grade 1 to 2 in intensity. Most common AEs were: injection site reactions, abdominal pain, anorexia, chromaturia, constipation, dyspnea, fatigue, headache, pain at the injection site, nausea, vomiting, and fever. CONCLUSIONS: Although RPI.4610 demonstrated a well-tolerated safety profile, its lack of clinical efficacy precludes this drug from further development.
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Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , ARN Catalítico/uso terapéutico , Adulto , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/secundario , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , ARN Catalítico/efectos adversos , Receptor 1 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidoresRESUMEN
Recently published clinical trial data have produced compelling evidence for increased survival when Herceptin is administered to patients whose tumors are HER2 amplified. Therefore, the accuracy of HER2 status is essential to determine which patients should or should not receive Herceptin. Although HER2 results obtained by FISH and IHC are often in agreement, there is a persistent group of cases in which results are discordant, particularly among tumors with intermediate results. A multivariable analysis was undertaken to determine relative significance of various clinical and pathologic findings for patients diagnosed with infiltrating ductal carcinoma, and a data model was produced that predicts which patients are most likely to have HER2 amplified tumors. Correlates of HER2 amplification were higher Scarff-Bloom-Richardson grade, younger age at diagnosis, and a comedo ductal carcinoma in situ component.
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Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patología , Genes erbB-2/genética , Modelos Estadísticos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Femenino , Amplificación de Genes/fisiología , Humanos , Hibridación Fluorescente in Situ , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Receptor ErbB-2/metabolismo , Sistema de RegistrosRESUMEN
PURPOSE: This study intended to determine the maximum tolerated dose, safety, pharmacokinetic variables, clinical response, and pharmacodynamic markers of daily s.c. administration of Angiozyme. PATIENTS AND METHODS: Patients with refractory solid tumors were enrolled in a dose escalation and expanded cohort design. Dose escalation involved cohorts of patients at doses of 10, 30, 100, or 300 mg/m(2)/d for 29 days. A second component enrolled 15 additional patients at a daily dose of 100 mg/m(2). Patients were eligible to continue on therapy until disease progression. RESULTS: Thirty-one patients were enrolled and 28 were evaluable (range, 29-505 days; median, 89.5 days). A maximum tolerated dose was not defined by toxicity but rather by the maximal deliverable dose of 300 mg/m(2)/d. Grade 1 to 2 injection site reactions were the most common toxicities. One patient in the 300 mg/m(2) group experienced a reversible grade 3 injection site reaction. Angiozyme showed dose-dependent plasma concentrations with good bioavailability. Surrogate markers showed Angiozyme localization in tumor biopsies and a significant increase in serum von Willebrand factor antigen, a marker for endothelial cell dysfunction. Although Angiozyme-reactive antibody production was noted for some patients, no antibody-related adverse events were noted. Seven of 28 (25%) evaluable patients had stable disease for >or =6 months, with the longest treatment duration of > or =16 months. Two patients (nasopharyngeal carcinoma and melanoma) showed minor responses. CONCLUSION: Angiozyme was well tolerated with satisfactory pharmacokinetic variables for daily s.c. dosing. Results have provided the basis for subsequent clinical trials of this first-of-class biologically targeted therapeutic.
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Inhibidores de la Angiogénesis/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , ARN Catalítico/uso terapéutico , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Inhibidores de la Angiogénesis/efectos adversos , Inhibidores de la Angiogénesis/farmacocinética , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias/irrigación sanguínea , Neoplasias/genética , ARN Catalítico/efectos adversos , ARN Catalítico/genética , ARN Catalítico/farmacocinética , Resultado del Tratamiento , Factor de von Willebrand/metabolismoRESUMEN
PURPOSE: The role of multidisciplinary care (MDC) on cancer care processes is not fully understood. We investigated the impact of MDC on the processes of care at cancer centers within the National Cancer Institute Community Cancer Centers Program (NCCCP). METHODS: The study used data from patients diagnosed with stage IIB to III rectal cancer, stage III colon cancer, and stage III nonsmall-cell lung cancer at 14 NCCCP cancer centers from 2007 to 2012. We used an MDC development assessment toolwith levels ranging from evolving MDC (low) to achieving excellence (high)to measure the level of MDC implementation in seven MDC areas, such as case planning and physician engagement. Descriptive statistics and cluster-adjusted regression models quantified the association between MDC implementation and processes of care, including time from diagnosis to treatment receipt. RESULTS: A total of 1,079 patients were examined. Compared with patients with colon cancer treated at cancer centers reporting low MDC scores, time to treatment receipt was shorter for patients with colon cancer treated at cancer centers reporting high or moderate MDC scores for physician engagement (hazard ratio [HR] for high physician engagement, 2.66; 95% CI, 1.70 to 4.17; HR for moderate physician engagement, 1.50; 95% CI, 1.19 to 1.89) and longer for patients with colon cancer treated at cancer centers reporting high 2MDC scores for case planning (HR, 0.65; 95% CI, 0.49 to 0.85). Results for patients with rectal cancer were qualitatively similar, and there was no statistically significant difference among patients with lung cancer. CONCLUSION: MDC implementation level was associated with processes of care, and direction of association varied across MDC assessment areas.
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Neoplasias/epidemiología , Readmisión del Paciente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Maryland/epidemiología , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/terapia , Factores de Riesgo , Adulto JovenRESUMEN
The inhibitor of apoptosis (IAP) family of antiapoptotic proteins has been identified as a target for small molecule inhibitors in cancer. Second mitochondrial-derived activator of caspases (SMAC) efficiently and naturally antagonizes IAPs, and preclinical studies have determined that SMAC mimetics have potent anticancer properties. Here, we report a first-in-human trial designed to determine the maximum tolerated dose (MTD), safety, and pharmacokinetics/pharmacodynamics (PK/PD) of birinapant, a novel SMAC mimetic. Patients with advanced solid tumors or lymphoma were enrolled in a 3+3 dose escalation design with birinapant administered intravenously from 0.18 to 63 mg/m(2) once weekly every 3 of 4 weeks. Fifty patients were enrolled to 12 dose cohorts. Birinapant 47 mg/m(2) was determined to be the MTD. At 63 mg/m(2), dose-limiting toxicities included headache, nausea, and vomiting. Two cases of Bell's palsy (grade 2) also occurred at 63 mg/m(2). Birinapant had a plasma half-life of 30 to 35 hours and accumulated in tumor tissue. Birinapant suppressed cIAP1 and increased apoptosis in peripheral blood mononuclear cells and tumor tissue. Prolonged stable disease was observed in 3 patients: non-small cell lung cancer (5 months), colorectal cancer (5 months), and liposarcoma (9 months). Two patients with colorectal cancer had radiographic evidence of tumor shrinkage. In conclusion, birinapant was well tolerated with an MTD of 47 mg/m(2) and exhibited favorable PK and PD properties. Several patients demonstrated stable disease and evidence of antitumor activity. These results support the ongoing clinical trials of birinapant in patients with cancer.
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Dipéptidos/uso terapéutico , Indoles/uso terapéutico , Linfoma/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Área Bajo la Curva , Western Blotting , Dipéptidos/efectos adversos , Dipéptidos/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Resistencia a Antineoplásicos , Femenino , Cefalea/inducido químicamente , Humanos , Indoles/efectos adversos , Indoles/farmacocinética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Linfoma/patología , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Neoplasias/patología , Resultado del Tratamiento , Vómitos/inducido químicamenteRESUMEN
This study examined the effect of the Baby-Friendly Hospital Initiative (BFHI) on the breastfeeding rate in Taiwan and analyzed factors related to BFHI qualification. The assessments included 56 hospitals enlisted for appraisal and 7,563 mothers in the maternity wards of these hospitals. Among the 56 hospitals appraised, 38 (67.9%) passed appraisal. Geographically, 88.5% (23/38) of hospitals are located in northern Taiwan, and only one hospital is situated in eastern Taiwan. All 13 medical centers enlisted for appraisal were qualified as BFHI. Only one private clinic passed the appraisal. We found close correlation between the location of the hospital and passing the appraisal (chi2 = 12.71, p < 0.01), and between the grade of a hospital and BFHI qualification (chi2 = 9.17, p < 0.05). Of the 10 steps to successful breastfeeding practiced in these hospitals, we found that step 10 got the highest scores, with a gain point rate of 94.64%; nonetheless, step 1 had significant power of discrimination regarding appraisal. Statistically, steps 7, 1, and 2 were more significant than any of the other steps. Mothers in qualified baby-friendly hospitals had higher breastfeeding rates than those in non-qualified hospitals, whether they were surveyed while in maternity wards after delivery (88.1% vs 78.1%) or in their first postnatal month (67.6% vs 59.4%). In conclusion, our study indicates that health policy intervention has a significant impact on increasing the breastfeeding rate in Taiwan.
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Lactancia Materna/estadística & datos numéricos , Política de Salud , Femenino , Hospitales , Humanos , Lactante , Recién Nacido , TaiwánRESUMEN
The acquisition of apoptosis resistance is a fundamental event in cancer development. Among the mechanisms used by cancer cells to evade apoptosis is the dysregulation of inhibitor of apoptosis (IAP) proteins. The activity of the IAPs is regulated by endogenous IAP antagonists such as SMAC (also termed DIABLO). Antagonism of IAP proteins by SMAC occurs via binding of the N-terminal tetrapeptide (AVPI) of SMAC to selected BIR domains of the IAPs. Small molecule compounds that mimic the AVPI motif of SMAC have been designed to overcome IAP-mediated apoptosis resistance of cancer cells. Here, we report the preclinical characterization of birinapant (TL32711), a bivalent SMAC-mimetic compound currently in clinical trials for the treatment of cancer. Birinapant bound to the BIR3 domains of cIAP1, cIAP2, XIAP, and the BIR domain of ML-IAP in vitro and induced the autoubiquitylation and proteasomal degradation of cIAP1 and cIAP2 in intact cells, which resulted in formation of a RIPK1:caspase-8 complex, caspase-8 activation, and induction of tumor cell death. Birinapant preferentially targeted the TRAF2-associated cIAP1 and cIAP2 with subsequent inhibition of TNF-induced NF-κB activation. The activity of a variety of chemotherapeutic cancer drugs was potentiated by birinapant both in a TNF-dependent or TNF-independent manner. Tumor growth in multiple primary patient-derived xenotransplant models was inhibited by birinapant at well-tolerated doses. These results support the therapeutic combination of birinapant with multiple chemotherapies, in particular, those therapies that can induce TNF secretion.
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Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Dipéptidos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Indoles/farmacología , Animales , Neoplasias de la Mama/patología , Caspasa 8/metabolismo , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones Desnudos , Proteínas Mitocondriales/metabolismo , Receptores del Factor de Necrosis Tumoral , Transducción de Señal/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/metabolismoRESUMEN
IPI-504 is a novel, highly soluble small-molecule inhibitor of heat shock protein 90 (Hsp90), a protein chaperone essential for regulating homeostasis of oncoproteins and cell signaling proteins. Human epidermal growth factor receptor 2 (HER2; ErbB2) oncoprotein, expressed in a subset of metastatic breast cancers, is a Hsp90 client protein. In this study, we investigated the antitumor activity and the mechanism of action of IPI-504 in HER2(+), trastuzumab-sensitive and trastuzumab-refractory cell lines in vitro and in vivo. IPI-504 exhibited potent antiproliferative activities (range of IC(50), 10-40 nmol/L) against several tumor cell lines examined, whereby mechanism of action was mediated through HER2 and Akt degradation. Both intravenous and oral administration of IPI-504 assessed in multiple schedules showed potent tumor growth inhibition in vivo with corresponding degradation of HER2. The tolerability and efficacy of IPI-504 combined with either trastuzumab or lapatinib were also investigated in HER2(+) tumor xenograft models. Combination of IPI-504 with trastuzumab significantly enhanced tumor growth delay and induced greater responses when compared with either agent alone. Although, as expected, trastuzumab alone did not exhibit any significant antitumor activity in the trastuzumab-resistant JIMT-1 model, IPI-504 administered in combination with trastuzumab yielded greater antitumor efficacy than either agent alone. Finally, combination of IPI-504 and lapatinib was well tolerated up to 50 mg/kg IPI-504 and 100 mg/kg lapatinib and resulted in significant delay in tumor growth, including partial and complete tumor responses. These lines of evidence support the development of IPI-504 in HER2-positive breast cancers as a single agent and in combination with either trastuzumab or lapatinib
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Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Benzoquinonas/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Lactamas Macrocíclicas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Sinergismo Farmacológico , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Lapatinib , Quinazolinas/farmacología , Receptor ErbB-2/metabolismo , Trastuzumab , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Changes to TNM staging criteria for breast cancer, introduced in 2003, have resulted in stage re-classification for some tumors. The most frequently implemented change has resulted in tumors associated with more than three positive axillary nodes being upstaged. We hypothesize these TNM staging changes would result in more TNM Stage IIB, IIIA, and IIIB tumors and that disease-specific survival estimates would change under the new staging system. METHODS: A review of data was completed for patients diagnosed with breast cancer between 1 January 1995 and 31 December 2000. Tumors that would have been staged differently under the 2003 system were identified and re-classified. Clinical outcomes were determined and disease-specific survival estimates were compared relative to TNM Stage using the old and new staging systems. Data were analyzed using the log-rank test and the method of Kaplan and Meier was used to generate survival curves. RESULTS: Data were available for 2492 tumors, of which 919 were candidates for re-classification, including 829 old Stage II, 59 old Stage III, and 31 old Stage IV. Of these 919, 159 (17%) underwent stage re-classification using the new system. Separate survival estimates for patients who had been under old stage IIA/B, IIIA/B were generated; patients upstaged from IIA or IIB demonstrated a significant difference in survival. CONCLUSIONS: Stage specific survival curves indicated decreased survival for patients whose tumors had been upstaged from IIA or IIB under the old system; survival for all other patients remained unchanged.
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Neoplasias de la Mama/clasificación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Supervivencia , Tasa de SupervivenciaRESUMEN
BACKGROUND: We performed this study to determine the prognostic significance of clinical tumor size, pathologic measurement of residual tumor, and number of positive axillary nodes in the surgical specimen relative to overall survival for patients who underwent primary induction chemotherapy for advanced breast cancer. METHODS: Data, collected prospectively between 1997 and 2002, included clinical tumor-node-metastasis stage, age at diagnosis, hormone receptor status, type of preoperative chemotherapy, histological type, surgical procedure, pathologic measurement in centimeters of residual breast tumor, and the number of positive axillary nodes in the surgical specimen. Univariable correlates of residual breast disease were assessed by using the chi2 test. Recursive partitioning analysis was used to determine the prognostic significance of clinical tumor size, residual tumor size, and pathologic node involvement relative to overall survival. Survival was estimated by using the method of Kaplan and Meier and compared by using the log-rank test. A P value of <.05 was considered significant. RESULTS: Data were available for 85 patients with advanced breast cancer. Although univariable analysis identified increasing age, clinically involved axillary nodes, and a higher clinical tumor-node-metastasis stage as predictors of an increased risk of residual disease, recursive partitioning analysis identified more than three involved axillary nodes in the surgical specimen, with or without any measurable residual breast disease, as the most significant predictor of decreased survival (P<.001). CONCLUSIONS: Pathologic axillary node involvement was the most significant predictor of decreased survival for patients who had undergone primary induction chemotherapy for advanced breast cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/secundario , Carcinoma Lobular/secundario , Ganglios Linfáticos/patología , Axila , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/mortalidad , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/mortalidad , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Mastectomía , Persona de Mediana Edad , Neoplasia Residual , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
Tumor vaccine after high-dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) aims at directing immune recovery toward tumor responses after optimizing minimal residual disease. We have characterized T-cell recovery and tumor response after a regimen devised as a platform for such immunotherapy. One hundred patients with high-risk or metastatic breast cancer received 3 to 7 cycles of paclitaxel and cyclophosphamide (overall response rate, 78%) and then HDC with melphalan and etoposide. Seventy-one patients received HDC and ASCT (no mortality at 100 days). At 24 months after transplantation, progression-free and overall survival probabilities for patients with stage IIIA, IIIB, and IV disease were 82%, 81%, and 42% and 100%, 94%, and 68%, respectively. The median progression-free and overall survivals from entry on study for stage IV patients were 15.3 and 38.1 months, respectively. CD3 + , CD8 + , and CD4 + cells were severely depleted after ASCT. Although total CD8 + T-cell numbers approached the normal range by 3 months, most of these cells were CD28 - . Naive CD45RA + CD4 + T cells approached the normal range only 18 months after ASCT and only in younger patients. The described observations provide the basis for devising a strategy for cancer vaccine administration after ASCT. Incorporating immune reconstitution enhancement after ASCT may be advantageous.
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Neoplasias de la Mama/terapia , Vacunas contra el Cáncer/administración & dosificación , Trasplante de Células Madre Hematopoyéticas , Recuperación de la Función , Vacunación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Vacunas contra el Cáncer/inmunología , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/inmunología , Trasplante AutólogoRESUMEN
OBJECTIVE: The aim of this study was to examine whether midtrimester maternal serum free beta-human chorionic gonadotropin and alpha-fetoprotein levels for Down syndrome screening differed in vegetarian pregnancies and omnivore pregnancies and to evaluate whether maternal serum vitamin B(12) concentration affected these maker levels. STUDY DESIGN: Ninety-eight vegetarian and 122 omnivore singleton pregnancies were studied. Reference levels of free beta-human chorionic gonadotropin and alpha-fetoprotein were based on a population of 6312 singleton euploid pregnancies that had been surveyed previously. Serum free beta-human chorionic gonadotropin and alpha-fetoprotein levels were measured by enzyme immunoassay or radioimmunoassay. Multiples of the median values were calculated to determine whether different diet habits affected serum biomarker levels. Maternal serum vitamin B(12) levels were determined with radioimmunoassay. RESULTS: The free beta-human chorionic gonadotropin multiples of the median values were elevated significantly in the vegetarian pregnancies group (1.28 multiples of the median) compared with that of the reference population (1.00 multiples of the median) (P<.001). A negative association between the serum free beta-human chorionic gonadotropin multiples of the median values and the concentration of maternal serum vitamin B(12) was observed in the vegetarian pregnancies. No correlation was found between the alpha-fetoprotein multiples of the median values and the maternal serum vitamin B(12) concentration. CONCLUSION: The current data showed that the midtrimester maternal serum free beta-human chorionic gonadotropin levels increased in vegetarian pregnancies and led to an elevated false-positive rate in screening for Down syndrome compared with pregnant women with regular diet and resulted in unnecessary invasive procedures. It is necessary to establish vegetarian pregnancy alpha-fetoprotein and beta-human chorionic gonadotropin reference levels to correct increased false-positive screening results.