475 research outputs found

    Rethinking neoadjuvant chemotherapy for breast cancer

    Get PDF
    Breast cancer is the most common cancer in women worldwide. In 2014, 55 000 women in the UK were given the diagnosis of breast cancer, and 11 000 died.1 Early breast cancer is traditionally treated with surgery, plus radiotherapy and adjuvant systemic therapy as required. Neoadjuvant chemotherapy for breast cancer is a new strategy that was introduced towards the end of the 20th century with the aim of reducing tumour size. It has four main rationales. Firstly, it should render an otherwise inoperable tumour operable or, secondly, allow more conservative surgery. Thirdly, starting systemic treatment preoperatively was hoped to lead to improved overall survival in patients with locally advanced cancers, who are at high risk of having distant disease. Finally, unlike adjuvant chemotherapy given in the absence of any measurable disease, neoadjuvant chemotherapy gives us the opportunity to observe the tumour shrink both palpably and on imaging, enabling a rapid assessment of clinical response. This could help test responses in vivo to new drug regimens, which could then be used as adjuvant therapies, in so called window of opportunity studies. A survey of multidisciplinary teams in Australia, Germany, Italy, the UK, and the US found that 7-27% of new breast cancers are treated with neoadjuvant chemotherapy (Saunders C, Cody H, Kolberg HC, et al, personal communication, 2017). With 1.7 million women receiving diagnoses annually, this translates into 120 000-460 000 women receiving neoadjuvant chemotherapy worldwide.1 Although data indicate that the first rationale remains valid, the others have not led to the desired outcomes. More conservative surgery after neoadjuvant chemotherapy can result in a higher rate of local recurrence, and, despite the earlier initiation of systemic treatment, no improvement in survival has been seen.234 Furthermore, neoadjuvant chemotherapy may not help test novel chemotherapies—although primary tumour response is a good indicator of prognosis for a particular treatment, it is counterintuitively a poor surrogate marker for the overall survival benefit when evaluating novel chemotherapy regimens. Finally, for 40-80% of patients, even the best neoadjuvant chemotherapy regimens extend the period the cancer remains in the breast and can make surgery more difficult, as the tumour is less easily palpable and the axillary lymph nodes are less distinct. We question the wisdom of the current widespread use of neoadjuvant chemotherapy

    An international randomised controlled trial to compare targeted intra-operative radiotherapy (TARGIT) with conventional post-operative radiotherapy after conservative breast surgery for women with early stage breast cancer (The TARGIT-A trial)

    Get PDF
    BACKGROUND: Based on our laboratory work and clinical trials we hypothesised that radiotherapy after lumpectomy for breast cancer could be restricted to the tumour bed. In collaboration with the industry we developed a new radiotherapy device and a new surgical operation for delivering single-dose radiation to the tumour bed - the tissues at highest risk of local recurrence. We named it TARGeted Intraoperative radioTherapy (TARGIT). From 1998 we confirmed its feasibility and safety in pilot studies. OBJECTIVE: To compare TARGIT within a risk-adapted approach with whole breast external beam radiotherapy over several weeks (EBRT). DESIGN AND SETTING: The TARGIT-A trial was a pragmatic, prospective, international, multicenter, non-inferiority, non-blinded, randomised (1:1 ratio), clinical trial from 33 centres in 11 countries. Originally, randomisation occurred before initial lumpectomy (prepathology) and if allocated TARGIT, the patient received it during the lumpectomy. Subsequently, the postpathology stratum was added, in which randomisation occurred after initial lumpectomy, allowing potentially easier logistics and a more stringent case selection, but needed a reoperation to reopen the wound to give TARGIT as delayed procedure. Risk-adapted approach meant that in the experimental arm, if pre-specified unsuspected adverse factors were found postoperatively after receiving TARGIT, then EBRT was recommended. Pragmatically, this reflected how TARGIT would be practiced in the real world. PARTICIPANTS: Women who were >=45 years of age with unifocal invasive ductal carcinoma preferably <= 3.5cm in size; 3451 patients were recruited between March 2000 and June 2012. OUTCOMES: Primary: absolute difference in local recurrence, with a non-inferiority margin of 2.5%. Secondary: included toxicity, breast cancer specific and non-breast-cancer mortality. RESULTS: Values below are 5-year Kaplan-Meier rates for TARGIT vs. EBRT. There was no statistically significant difference in local recurrence between TARGIT and EBRT. TARGIT was non-inferior to EBRT overall (3·3%(2·1–5·1) vs. 1·3%(0·7–2·5),p=0.04,Pnoninferiority =0.00000012) and in the prepathology stratum(n=2298) when TARGIT was given concurrently with lumpectomy(2·1%(1·1–4·2) vs. 1·1%(0·5–2·5),p=0.31,Pnoninferiority =0.0000000013). With delayed TARGIT postpathology,(n=1153) the between-group difference was larger than 2·5% and non-inferiority was not established for this stratum((5·4%(3·0–9·7) vs. 1·7%(0·6–4·9),p=0.069,Pnoninferiority= 0.06640). The local-recurrence-free survival when TARGIT was given with lumpectomy was 93.9%(95%CI 90.9 – 95.9) vs. EBRT: 92.5%(95%CI 89.7 – 94.6),p=0.35. In a planned subgroup analysis, progesterone (PgR) receptor status was found to be the only predictor of outcome - hormone responsive patients (PgRpositive) had similar 5-year local recurrence with TARGIT during lumpectomy 1.4%(0.5-3.9) vs. EBRT 1.2%(0.5-2.9),p=0.77. Grade 3 or 4 radiotherapy toxicity was significantly reduced with TARGIT. Overall, breast cancer mortality was much the same between groups (2·6%[1·5–4·3] vs. 1·9%[1·1–3·2];p=0·56) but there were significantly fewer non-breast-cancer deaths with TARGIT (1·4% [0·8–2·5] vs 3·5%[2·3–5·2];p=0·0086), attributable to fewer deaths from cardiovascular causes and other cancers, leading to a trend in reduced overall mortality in the TARGIT arm 37 deaths, 3·9%(2·7–5·8) vs. 51 deaths, 5·3%(3·9–7·3),p=0.099). Health economic analyses suggest that TARGIT was statistically significantly less costly than EBRT, produced similar QALYs, had a positive incremental Net Monetary Benefit that was borderline statistically significant from zero, and had a probability of over 90% of being cost-effective. There appears to be little uncertainty in the point estimates, based on deterministic and probabilistic sensitivity analyses. If TARGIT were given instead of EBRT in suitable patients, it might potentially reduce costs to the health care providers by £8 million to £9.1 million each year. This does not include environmental, patient and societal costs. LIMITATIONS: The number of local recurrences is small however, the number of events for local-recurrence-free survival is not small (59 vs. 61); Occurrence of only a few events implies that the treatments are effective and any difference is unlikely to be large. The follow up not all 3451 patients is 5 years, although the number required to answer the main trial question (n=585) have more than 5 years follow up. FUTURE WORK: We shall repeat the analyses with longer follow up. Although this may not change the primary result, the larger number of events may confirm the effect on mortality and allow more detailed subgroup analyses. The TARGIT-B trial is testing whether TARGIT-Boost is superior to EBRT boost. CONCLUSION: For patients with breast cancer (women who are 45 years of age and older with hormone sensitive invasive ductal carcinoma that is up to 3.5cm in size), TARGIT concurrent with lumpectomy within a risk-adapted approach is as effective, safer and less expensive alternative to postoperative EBRT. TRIAL REGISTRATION: ISRCTN34086741, ClinicalTrials.gov NCT00983684

    Correlating 3D porous structure in polymer films with mass transport properties using FIB-SEM tomography

    Get PDF
    Porous polymer coatings are used to control drug release from pharmaceutical products. The coating covers a drug core and depending on the porous structure, different drug release rates are obtained. This work presents mass transport simulations performed on porous ethyl cellulose films with different porosities. The simulations were performed on high spatial resolution 3D data obtained using a focused ion beam scanning electron microscope. The effective diffusion coefficient of water was determined using a diffusion chamber. Lattice Boltzmann simulations were used to simulate water diffusion in the 3D data. The simulated coefficient was in good agreement with the measured coefficient. From the results it was concluded that the tortuosity and constrictivity of the porous network increase with decreasing amount of added hydroxypropyl cellulose, resulting in a sharp decrease in effective diffusion. This work shows that high spatial resolution 3D data is necessary, and that 2D data is insufficient, in order to predict diffusion through the porous structure with high accuracy

    Cavity QED with a Bose-Einstein condensate

    Full text link
    Cavity quantum electrodynamics (cavity QED) describes the coherent interaction between matter and an electromagnetic field confined within a resonator structure, and is providing a useful platform for developing concepts in quantum information processing. By using high-quality resonators, a strong coupling regime can be reached experimentally in which atoms coherently exchange a photon with a single light-field mode many times before dissipation sets in. This has led to fundamental studies with both microwave and optical resonators. To meet the challenges posed by quantum state engineering and quantum information processing, recent experiments have focused on laser cooling and trapping of atoms inside an optical cavity. However, the tremendous degree of control over atomic gases achieved with Bose-Einstein condensation has so far not been used for cavity QED. Here we achieve the strong coupling of a Bose-Einstein condensate to the quantized field of an ultrahigh-finesse optical cavity and present a measurement of its eigenenergy spectrum. This is a conceptually new regime of cavity QED, in which all atoms occupy a single mode of a matter-wave field and couple identically to the light field, sharing a single excitation. This opens possibilities ranging from quantum communication to a wealth of new phenomena that can be expected in the many-body physics of quantum gases with cavity-mediated interactions.Comment: 6 pages, 4 figures; version accepted for publication in Nature; updated Fig. 4; changed atom numbers due to new calibratio

    Telemonitoring for Patients With COVID-19:Recommendations for Design and Implementation

    Get PDF
    Despite significant efforts, the COVID-19 pandemic has put enormous pressure on health care systems around the world, threatening the quality of patient care. Telemonitoring offers the opportunity to carefully monitor patients with a confirmed or suspected case of COVID-19 from home and allows for the timely identification of worsening symptoms. Additionally, it may decrease the number of hospital visits and admissions, thereby reducing the use of scarce resources, optimizing health care capacity, and minimizing the risk of viral transmission. In this paper, we present a COVID-19 telemonitoring care pathway developed at a tertiary care hospital in the Netherlands, which combined the monitoring of vital parameters with video consultations for adequate clinical assessment. Additionally, we report a series of medical, scientific, organizational, and ethical recommendations that may be used as a guide for the design and implementation of telemonitoring pathways for COVID-19 and other diseases worldwide

    Spatio-Temporal Characteristics of Global Warming in the Tibetan Plateau during the Last 50 Years Based on a Generalised Temperature Zone - Elevation Model

    Get PDF
    Temperature is one of the primary factors influencing the climate and ecosystem, and examining its change and fluctuation could elucidate the formation of novel climate patterns and trends. In this study, we constructed a generalised temperature zone elevation model (GTEM) to assess the trends of climate change and temporal-spatial differences in the Tibetan Plateau (TP) using the annual and monthly mean temperatures from 1961-2010 at 144 meteorological stations in and near the TP. The results showed the following: (1) The TP has undergone robust warming over the study period, and the warming rate was 0.318°C/decade. The warming has accelerated during recent decades, especially in the last 20 years, and the warming has been most significant in the winter months, followed by the spring, autumn and summer seasons. (2) Spatially, the zones that became significantly smaller were the temperature zones of -6°C and -4°C, and these have decreased 499.44 and 454.26 thousand sq km from 1961 to 2010 at average rates of 25.1% and 11.7%, respectively, over every 5-year interval. These quickly shrinking zones were located in the northwestern and central TP. (3) The elevation dependency of climate warming existed in the TP during 1961-2010, but this tendency has gradually been weakening due to more rapid warming at lower elevations than in the middle and upper elevations of the TP during 1991-2010. The higher regions and some low altitude valleys of the TP were the most significantly warming regions under the same categorizing criteria. Experimental evidence shows that the GTEM is an effective method to analyse climate changes in high altitude mountainous regions

    Predictors of linkage to care following community-based HIV counseling and testing in rural Kenya

    Get PDF
    Despite innovations in HIV counseling and testing (HCT), important gaps remain in understanding linkage to care. We followed a cohort diagnosed with HIV through a community-based HCT campaign that trained persons living with HIV/AIDS (PLHA) as navigators. Individual, interpersonal, and institutional predictors of linkage were assessed using survival analysis of self-reported time to enrollment. Of 483 persons consenting to follow-up, 305 (63.2%) enrolled in HIV care within 3 months. Proportions linking to care were similar across sexes, barring a sub-sample of men aged 18–25 years who were highly unlikely to enroll. Men were more likely to enroll if they had disclosed to their spouse, and women if they had disclosed to family. Women who anticipated violence or relationship breakup were less likely to link to care. Enrolment rates were significantly higher among participants receiving a PLHA visit, suggesting that a navigator approach may improve linkage from community-based HCT campaigns.Vestergaard Frandse

    Anaesthetic considerations of adults with Morquio's syndrome - a case report

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The anaesthetic management of patients with Morquio syndrome is complicated by a number of factors including odontoid hypoplasia, atlantoaxial instability, thoracic kyphosis, and deposition of mucopolysaccharides in the soft tissue of the oropharnyx.</p> <p>Case presentation</p> <p>Herein we describe the anaesthetic considerations and management of a 26 year old adult with Morquio syndrome, who presented for an elective hip replacement.</p> <p>Conclusion</p> <p>This report details an awake fiberoptic intubation in an adult with Morquio syndrome. We recommend that this approach be considered in patients with Morquio syndrome undergoing general anaesthesia.</p

    The correlation and level of agreement between end-tidal and blood gas pCO2 in children with respiratory distress: a retrospective analysis

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>To investigate the correlation and level of agreement between end-tidal carbon dioxide (EtCO<sub>2</sub>) and blood gas pCO<sub>2 </sub>in non-intubated children with moderate to severe respiratory distress.</p> <p>Methods</p> <p>Retrospective study of patients admitted to an intermediate care unit (InCU) at a tertiary care center over a 20-month period with moderate to severe respiratory distress secondary to asthma, bronchiolitis, or pneumonia. Patients with venous pCO<sub>2 </sub>(vpCO<sub>2</sub>) and EtCO<sub>2 </sub>measurements within 10 minutes of each other were eligible for inclusion. Patients with cardiac disease, chronic pulmonary disease, poor tissue perfusion, or metabolic abnormalities were excluded.</p> <p>Results</p> <p>Eighty EtCO<sub>2</sub>-vpCO<sub>2 </sub>paired values were available from 62 patients. The mean ± <smcaps>SD</smcaps> for EtCO<sub>2 </sub>and vpCO<sub>2 </sub>was 35.7 ± 10.1 mmHg and 39.4 ± 10.9 mmHg respectively. EtCO<sub>2 </sub>and vpCO<sub>2 </sub>values were highly correlated (r = 0.90, p < 0.0001). The correlations for asthma, bronchiolitis and pneumonia were 0.74 (p < 0.0001), 0.83 (p = 0.0002) and 0.98 (p < 0.0001) respectively. The mean bias ± <smcaps>SD</smcaps> between EtCO<sub>2 </sub>and vpCO<sub>2 </sub>was -3.68 ± 4.70 mmHg. The 95% level of agreement ranged from -12.88 to +5.53 mmHg. EtCO<sub>2 </sub>was found to be more accurate when vpCO<sub>2 </sub>was 35 mmHg or lower.</p> <p>Conclusion</p> <p>EtCO<sub>2 </sub>is correlated highly with vpCO<sub>2 </sub>in non-intubated pediatric patients with moderate to severe respiratory distress across respiratory illnesses. Although the level of agreement between the two methods precludes the overall replacement of blood gas evaluation, EtCO<sub>2 </sub>monitoring remains a useful, continuous, non-invasive measure in the management of non-intubated children with moderate to severe respiratory distress.</p
    • …
    corecore