Cross-border referral for early breast cancer: an analysis of radiation fractionation patterns

Because of increasing waiting times for adjuvant radiation in the province of Ontario, patients from one Canadian centre were referred to two centres in the United States. This situation provided an opportunity to compare radiation practices.We performed a retrospective review of radiation prescribed to patients following breast-conserving surgery for invasive breast cancer. Patients with positive margins, 4 or more positive lymph nodes, recurrent disease, or large tumours (>5 cm) were excluded. For comparison, we reviewed a random sample of similar patients treated at the Canadian centre during the same period. A total of 120 referred and 217 non-referred patients were eligible for comparison. The analysis included 98 pairs of patients (N = 196), fully matched on age, nodal status, T stage, grade, and estrogen receptor (er) status.Mean patient age was 60.7 years. The median total dose and number of fractions differed between centres [6040 cGy in 32 fractions (United States) vs. 4250 cGy in 16 fractions (Canadian), both p < 0.001). Boost was used more often in the United States (97% vs. 9%, p < 0.001). Variation in prescribing patterns was seen. In the United States, seven different schedules for whole-breast irradiation were used; at the Canadian centre, two schedules were prescribed. Predicted radiobiologic effects of these schedules were calculated to be similar.Differences in fractionation patterns were observed between and within U.S. and Canadian centres. Such variability is likely to affect patient convenience and resource utilization. Although patient selection, referring surgeon, and change in policies may account for some of the observed differences, further research is necessary to better understand the causes.     

MRI/PET Imaging in elevated PSA and localized prostate cancer: a narrative review

ObjectiveTo review the recent milestones in MRI and PET based imaging and evaluate their evolving role in the setting of elevated PSA as well as localized prostate cancer.BackgroundThe importance of multiparametric MRI (mpMRI) and PET based imaging for the diagnosis and staging of prostate cancer cannot be understated. Accurate staging has become another significant milestone with the use of PET scans, particularly with prostate specific radiotracers like 68-Gallium Prostate Specific Membrane Antigen (68Ga-PSMA). Integrated PET/MRI systems are commercially available and can be modulated to evaluate the unique needs of localized as well as recurrent prostate cancer.MethodsA literature search was performed using PubMed and Google Scholar using the MeSH compliant and other keywords that included prostate cancer, PSA, mpMRI, PET CT, PET/MRI.ConclusionsmpMRI has now established itself as the gold-standard of local prostate imaging and has been incorporated into international guidelines as part of the diagnostic work-up of prostate cancer. PSMA PET/CT has shown superiority over conventional imaging even in staging of localized prostate cancer based on recent randomized control data. Imaging parameters from PET/MRI have been shown to be associated with malignancy, Gleason score and tumour volume. As mpMRI and PSMA PET/CT become more ubiquitous and established; we can anticipate more high-quality data, cost optimization and increasing availability of PET/MRI to be ready for primetime in localized prostate cancer.     

Translational initiation in Leishmania tarentolae and Phytomonas serpens (Kinetoplastida) is strongly influenced by pre-ATG triplet and its 5' sequence context

To investigate the influence of sequence context of translation initiation codon on translation efficiency in Kinetoplastida, we constructed a library of expression plasmids randomized in the three nucleotides prefacing ATG of a reporter gene encoding enhanced green fluorescent protein (EGFP). All 64 possible combinations of pre-ATG triplets were individually stably integrated into the rDNA locus of Leishmania tarentolae and the resulting cell lines were assessed for EGFP expression. The expression levels were quantified directly by measuring the fluorescence of EGFP protein in living cells and confirmed by Western blotting. We observed a strong influence of the pre-ATG triplet on the level of protein expression over a 20-fold range. To understand the degree of evolutionary conservation of the observed effect, we transformed Phytomonas serpens, a trypanosomatid parasite of plants, with a subset of the constructs. The pattern of translational efficiency mediated by individual pre-ATG triplets in this species was similar to that observed in L. tarentolae. However, the pattern of translational efficiency of two other proteins (red fluorescent protein and tetracycline repressor) containing selected pre-ATG triplets did not correlate with either EGFP or each other. Thus, we conclude that a conserved mechanism of translation initiation site selection exists in kinetoplastids that is strongly influenced not only by the pre-ATG sequences but also by the coding region of the gene.     

Public knowledge of heart attack in a Nepalese population survey

OBJECTIVE: Limited knowledge of heart attack symptoms may prevent patients from seeking time-dependent thrombolytic therapy, an intervention that offers impressive survival benefit. Previous studies carried out in developed countries demonstrated a deficit of knowledge about a wide range of heart attack symptoms. The aim of this study was to describe knowledge of heart attack, knowledge of heart attack symptoms, and anticipated first response to symptoms among the lay public in Nepal. METHODS: A total of 1192 participants (657 men and 535 women age 16 to 88 years old) were interviewed in a cross-sectional manner. Those <16 years of age, all health professionals, and individuals with a history of heart attack were excluded. RESULTS: A total of 862 (72.3%) participants had heard of heart attack. Significantly more male than female participants had heard of heart attack (P <.001). Of the respondents, 91.7% with >or=10 years of education (ED-2) had heard of heart of attack, whereas only 54% respondents with <10 years of education or who were illiterate (unable to read and write) (ED-1) had heard of heart attack, and in both the male and female populations, a higher percentage of the ED-2 group had heard of heart attack than the ED-1 group (92.6% vs. 60% and 85.6% vs. 49.6%, respectively). A significantly higher number of respondents from 31 to 50 years of age (AGE-2) had heard of heart attack than those 16 to 30 years of age (AGE-1) and those >50 years of age (AGE-3) (P <.001). Among 862 respondents who had heard of heart attack, 21.3% could not name any heart attack symptoms. A total of 16 different heart attack symptoms were named. Fainting or collapsing (48%), chest pain (22.4%), shortness of breath (9%), dizziness (8.4%), palpitations (7.4%), and sweating (7.4%) were the leading symptoms named by respondents. Fainting or collapsing and chest pain and shortness of breath were named more frequently among the ED-2 group respondents and the AGE-3 group men. Only 3.7% could name >or=2 typical heart attack symptoms. A significantly larger number of the ED-2 group named >or=2 typical symptoms than their counterparts (P <0.001). A large number (77.6%) of respondents preferred immediate hospital referral and/or doctor consultation after a heart attack. CONCLUSIONS: In Nepal, better-educated men are more aware of heart attack. Fainting or collapsing and chest pain and shortness of breath were leading heart attack symptoms named by the general population. Public heart attack awareness is not adequate and knowledge of wide range of heart attack symptoms is deficient in the Nepalese general population.