RESUMO
UNLABELLED: The effects of bisphosphonates on altered bone turnover marker (BTM) levels associated with adjuvant endocrine or chemotherapy in early breast cancer have not been systematically investigated. In ProBONE II, zoledronic acid decreased these elevated BTM levels and increased bone mineral density (BMD) during adjuvant therapy, consistent with its antiresorptive effects. INTRODUCTION: Adjuvant chemotherapy or endocrine therapy for early hormone receptor-positive breast cancer (HR(+) BC) is associated with rapid BMD loss and altered BTM levels. Adjuvant bisphosphonate studies demonstrated BMD increases, but did not investigate BTM effects. The randomized, double-blind, ProBONE II study investigated the effect of adjuvant zoledronic acid (ZOL) on BMD and BTM in premenopausal women with early HR(+) BC. METHODS: Seventy premenopausal women with early HR(+) BC received adjuvant chemotherapy and/or endocrine therapy plus ZOL (4 mg IV every 3 months) or placebo for 24 months. Primary endpoint was change in lumbar spine BMD at 24 months versus baseline. Secondary endpoints included femoral neck and total femoral BMD changes, changes in BTM, and safety. RESULTS: Lumbar spine BMD increased 3.14% from baseline to 24 months in ZOL-treated participants versus a 6.43% decrease in placebo-treated participants (P < 0.0001). Mean changes in T- and Z-scores, and femoral neck and total femoral BMD, showed similar results. Bone resorption marker levels decreased â¼ 55% in ZOL-treated participants versus increases up to 65% in placebo-treated participants (P < 0.0001 for between-group differences). Bone formation marker (procollagen I N-terminal propeptide) levels decreased â¼ 57% in ZOL-treated participants versus increases up to 45% in placebo-treated participants (P < 0.0001 for between-group differences). Adverse events were consistent with the established ZOL safety profile and included one case of osteonecrosis of the jaw after a tooth extraction. CONCLUSIONS: Adding ZOL to adjuvant therapy improved BMD, reduced BTM levels, and was well tolerated in premenopausal women with early HR(+) BC receiving adjuvant chemotherapy and/or endocrine therapy.
Assuntos
Antineoplásicos/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Osteoporose/prevenção & controle , Adulto , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/farmacologia , Remodelação Óssea/efeitos dos fármacos , Neoplasias da Mama/fisiopatologia , Quimioterapia Adjuvante , Difosfonatos/efeitos adversos , Difosfonatos/farmacologia , Método Duplo-Cego , Feminino , Fêmur/fisiopatologia , Humanos , Imidazóis/efeitos adversos , Imidazóis/farmacologia , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente , Osteoporose/fisiopatologia , Pré-Menopausa/fisiologia , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Resultado do Tratamento , Adulto Jovem , Ácido ZoledrônicoRESUMO
Adjuvant treatment of breast cancer with aromatase inhibitors has been associated with increased bone loss. In this study, postmenopausal patients with oestrogen receptor positive breast cancer were randomised to exemestane for 5 years or tamoxifen for 2-2.5 years, followed by exemestane for 2-2.5 years. Levels of bone formation markers (bone specific alkaline phosphatase, amino terminal propeptide of type I procollagen, osteocalcin), and the bone resorption marker (carboxyterminal crosslinked telopeptide of type I collagen), were assessed at baseline and after 3, 6 and 12 months of treatment. Exemestane (n=78) resulted in increases from baseline in all bone turnover marker levels at all timepoints. In contrast, levels of all bone marker turnovers decreased with tamoxifen (n=83). Differences between tamoxifen and exemestane were statistically significant for all bone turnover markers at all timepoints. In conclusion, exemestane results in increases in markers of bone formation and resorption, while decreases are observed with tamoxifen.
Assuntos
Androstadienos/administração & dosagem , Antineoplásicos/administração & dosagem , Inibidores da Aromatase/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Tamoxifeno/administração & dosagem , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Reabsorção Óssea/induzido quimicamente , Quimioterapia Adjuvante , Colágeno Tipo I/sangue , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Osteocalcina/sangue , Peptídeos/sangue , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Adjuvant treatment of hormone receptor-positive breast cancer in postmenopausal women with aromatase inhibitors may be associated with increased bone loss. PATIENTS AND METHODS: Two hundred patients were randomised to receive exemestane or tamoxifen as adjuvant treatment of hormone receptor-positive breast cancer. Bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry at baseline and after 6 and 12 months treatment. RESULTS: One hundred and sixty-one patients were assessable. Tamoxifen treatment resulted in a 0.5% increase from baseline in BMD at the spine, which was maintained at 12 months. Exemestane-treated patients experienced a 2.6% decrease from baseline in BMD at the spine at 6 months and a further 0.2% decrease at 12 months. There were significant differences in the changes in BMD between tamoxifen and exemestane at 6 and 12 months (P = 0.0026 and P = 0.0008, respectively). The mean changes in BMD from baseline at the total hip were also significantly different between exemestane and tamoxifen at 6 and 12 months (P = 0.0009 and P = 0.04, respectively). There was no difference between tamoxifen and exemestane in mean changes in BMD from baseline at the femoral neck. CONCLUSIONS: Exemestane treatment resulted in an increase in bone loss at 6 months; bone loss stabilised after 6- to 12-month treatment.
Assuntos
Androstadienos/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Inibidores da Aromatase/efeitos adversos , Conservadores da Densidade Óssea/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Tamoxifeno/efeitos adversos , Idoso , Androstadienos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Quimioterapia Adjuvante , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Estudos Prospectivos , Tamoxifeno/uso terapêutico , Resultado do TratamentoRESUMO
OBJECTIVE: This study was performed in order to clarify the mechanisms which underlie the reduced signal-to-noise of event-related potentials in schizophrenic patients. Specifically, we wanted to find out, whether it is reduced activation and/or synchronization (phase-locking) in specific frequency bands of the ongoing EEG which is related to the decreased signal amplitude and signal-to-noise ratio in schizophrenics. METHODS: We investigated 41 unmedicated schizophrenics (10 of them drug-naïve) and compared them with healthy control subjects (n = 233) as well as unmedicated subjects with schizotypal personality (n = 21), who were considered to be high-risk subjects for schizophrenia, and unmedicated depressive patients (n = 71). We measured event-related activity during an acoustical choice reaction paradigm and calculated the signal-to-noise ratio, signal power and noise for a time interval of 50-200 ms after stimulus presentation. Signal-to-noise ratio was calculated from the power of the averaged trials (signal power) divided by the mean power of the single trials minus the power of the average (noise power). Also, we performed a frequency analysis of the pre- and poststimulus EEG based on a factor analytical approach. Group comparisons were performed with ANCOVA. RESULTS: As expected, a decreased signal-to-noise ratio of evoked activity was found in the schizophrenic and a non-significant trend in the schizotypal subjects and the depressive patients. We were able to show that the observed decrease is due to a reduced signal power and an increase of absolute noise power. Frequency analysis of the evoked activity revealed that normals, schizophrenics schizotypal subjects and depressive patients increased theta/delta activity between pre- and poststimulus interval to a similar extend. However, this theta/delta-augmentation does not correlate with signal power in schizophrenics. Also, normals and depressive subjects augment coherence between both temporal lobes during information processing, which is not found in schizophrenics and schizotypal subjects. In contrast, these two groups augment frontal lobe coherence, which goes along with an increase of noise. CONCLUSIONS: Reduced stimulus-induced phase-locking and bitemporal coherence of cortically evoked activity but not a failure to activate the cortex may be responsible for the observed low signal-to-noise ratio during information processing in schizophrenics. Accordingly, schizophrenics increase noise after stimulus presentation instead of building up a signal. This is discussed in the framework of the theory of stochastic resonance.