That three dimensional (3D) planning for radiation therapy (RT) of carcinoma of the prostate (CaP) improves radiation dosimetry to the tumour and reduces dose to the rectum and bladder compared with ...2D planning, has not been properly evaluated. We addressed this by downloading the CT data files of twenty-two patients who had completed 2D planned RT for CaP onto a 3D planning system and re-planning RT using the same four field technique and dose prescription as the 2D technique. The radiation dose at 100%, 90%, 50% and 0% volumes (D100, D90, D50 and D0) of the Dose Volume Histograms (DVH's) of the GTV, PTV, rectum and bladder, the area under the curves of each DVH and the field sizes were evaluated and compared between the two sets of plans. Repeated measured t-tests were used to compare the means of the different measurements. The D100, D90 and D50 of the GTV, PTV and rectum were increased for the 3D versus the 2D plans (p < 0.05 for each parameter). The area under the rectal DVH was also greater for the 3D plans (p < 0.05). These changes are attributable to the larger field sizes, particularly the length in the 3D compared with the 2D plans.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Purpose:
Normal tissue complication probability (NTCP) of the rectum, bladder, urethra, and femoral heads following several techniques for radiation treatment of prostate cancer were evaluated ...applying the relative seriality and Lyman models.
Methods:
Model parameters from literature were used in this evaluation. The treatment techniques included external (standard fractionated, hypofractionated, and dose-escalated) three-dimensional conformal radiotherapy (3D-CRT), low-dose-rate (LDR) brachytherapy (I-125 seeds), and high-dose-rate (HDR) brachytherapy (Ir-192 source). Dose-volume histograms (DVHs) of the rectum, bladder, and urethra retrieved from corresponding treatment planning systems were converted to biological effective dose-based and equivalent dose-based DVHs, respectively, in order to account for differences in radiation treatment modality and fractionation schedule.
Results:
Results indicated that with hypofractionated 3D-CRT (20 fractions of 2.75 Gy/fraction delivered five times/week to total dose of 55 Gy), NTCP of the rectum, bladder, and urethra were less than those for standard fractionated 3D-CRT using a four-field technique (32 fractions of 2 Gy/fraction delivered five times/week to total dose of 64 Gy) and dose-escalated 3D-CRT. Rectal and bladder NTCPs (5.2% and 6.6%, respectively) following the dose-escalated four-field 3D-CRT (2 Gy/fraction to total dose of 74 Gy) were the highest among analyzed treatment techniques. The average NTCP for the rectum and urethra were 0.6% and 24.7% for LDR-BT and 0.5% and 11.2% for HDR-BT.
Conclusions:
Although brachytherapy techniques resulted in delivering larger equivalent doses to normal tissues, the corresponding NTCPs were lower than those of external beam techniques other than the urethra because of much smaller volumes irradiated to higher doses. Among analyzed normal tissues, the femoral heads were found to have the lowest probability of complications as most of their volume was irradiated to lower equivalent doses compared to other tissues.
Summary Survival for adults and children with acute lymphoblastic leukaemia has risen substantially in recent years because use of improved risk-directed treatments and supportive care has widened. ...In nearly all developed countries, multidisciplinary panels of leukaemia experts have formulated clinical practice guidelines in which standard treatment approaches are recommended on the basis of current evidence. However, those guidelines do not take into account resource limitations in low-income countries, including financial and technical challenges. In Asia, huge disparities in economy and infrastructure exist between countries, and even among different regions in some large countries. At a consensus session held as part of the 2013 Asian Oncology Summit in Bangkok, Thailand, a panel of experts summarised recommendations for management of adult and paediatric acute lymphoblastic leukaemia. Strategies were developed for Asian countries on the basis of available financial, skill, and logistical resources and were stratified in a four-tier system according to the resources available in a particular country or region (basic, limited, enhanced, and maximum).
Radiation-induced mucositis is a common and serious side effect of radiotherapy. Molecular mechanisms of mucosal injury, however, are still poorly understood and extremely difficult to study in ...humans. A novel Dark Agouti rat model using fractionated radiotherapy to induce mucositis has been developed to investigate the occurrence of alimentary mucosal injury. Twenty-four Dark Agouti rats were randomly assigned to receive either fractionated radiotherapy or no radiotherapy. The irradiated rats received a fractionated course of abdominal radiotherapy at 45 Gy/18 fractions/6 weeks treating thrice weekly (i.e., at a radiation dose of 2.5 Gy per fraction). After each week of radiation, a group of irradiated rats was killed. Histomorphology and mucin distribution in the alimentary tract was investigated. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was used to examine apoptosis in the colon and jejunum, and intestinal morphometry was used to assess villus length, crypt length, and mitotic crypt count. Immunohistochemistry of p53, nuclear factor-kappaB, cyclooxygenase (COX)-1, and COX-2 was also done. The fractionated radiotherapy course induced alimentary mucositis from week 1, with more severe injury seen in the small intestine. The hallmark appearance of apoptosis was present in the crypts of the small and large intestine. In the jejunum and colon, goblet cell disorganization and degeneration was obvious and crypt mitotic counts were severely depleted throughout the treatment. Expression of p53, nuclear factor-kappaB, COX-1, and COX-2 was increased in the irradiated intestinal sections. Fractionated radiation-induced alimentary mucositis has been effectively documented in the Dark Agouti rat for the first time. Further studies investigating the molecular mechanisms underlying radiation-induced mucositis are planned to ultimately achieve anti-mucotoxic-targeted therapies.
Acute erythroid leukemia (AEL) is a high-risk leukemia of poorly understood genetic basis, with controversy regarding diagnosis in the spectrum of myelodysplasia and myeloid leukemia. We compared ...genomic features of 159 childhood and adult AEL cases with non-AEL myeloid disorders and defined five age-related subgroups with distinct transcriptional profiles: adult, TP53 mutated; NPM1 mutated; KMT2A mutated/rearranged; adult, DDX41 mutated; and pediatric, NUP98 rearranged. Genomic features influenced outcome, with NPM1 mutations and HOXB9 overexpression being associated with a favorable prognosis and TP53, FLT3 or RB1 alterations associated with poor survival. Targetable signaling mutations were present in 45% of cases and included recurrent mutations of ALK and NTRK1, the latter of which drives erythroid leukemogenesis sensitive to TRK inhibition. This genomic landscape of AEL provides the framework for accurate diagnosis and risk stratification of this disease, and the rationale for testing targeted therapies in this high-risk leukemia.
The Hong Kong government has launched the Elderly Health Care Voucher (EHCV) scheme to facilitate primary care in the private sector for older adults. This study aimed to examine whether voucher use ...was associated with a shift of healthcare burden from the public to the private sector, vaccine uptake and continuity of care.
This cross-sectional survey recruited older adults with ≥3 chronic diseases through convenience sampling from seven general outpatient clinics, seven geriatric day hospitals, and five specialist outpatient clinics of the public healthcare sector in Hong Kong. We used multiple logistic regression to address the study objective.
A total of 1032 patients participated in the survey. We included 714 participants aged 70 or above in the analysis. EHCV use was associated with higher utilization of private primary care services, including general practitioner and family doctor (Adjusted Odds Ratio (AOR) 2.67, 95% Confidence Interval (95%CI) 1.51-4.72) and Chinese medicine clinic (AOR 3.53, 95%CI 1.47-8.49). There were no significant associations of EHCV use with public general outpatient clinic attendance, Accident & Emergency attendance, and hospitalization. Furthermore, EHCV users were more likely to receive pneumococcal vaccination (AOR 2.17, 95%CI 1.22-3.85) and were less likely to visit the same doctors for chronic disease management (AOR 0.10, 95%CI 0.01-0.73).
While the EHCV may promote private primary care utilization and preventive care, older patients continue to rely on public services and the EHCV may worsen continuity of care. Policy-makers should designate voucher usage for chronic disease management and continuity of care.
Radiation-induced mucositis is a common and serious side effect of radiotherapy. Molecular mechanisms of mucosal injury, however, are still poorly understood and extremely difficult to study in ...humans. A novel Dark Agouti rat model using fractionated radiotherapy to induce mucositis has been developed to investigate the occurrence of alimentary mucosal injury. Twenty-four Dark Agouti rats were randomly assigned to receive either fractionated radiotherapy or no radiotherapy. The irradiated rats received a fractionated course of abdominal radiotherapy at 45 Gy/18 fractions/6 weeks treating thrice weekly (i.e., at a radiation dose of 2.5 Gy per fraction). After each week of radiation, a group of irradiated rats was killed. Histomorphology and mucin distribution in the alimentary tract was investigated. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay was used to examine apoptosis in the colon and jejunum, and intestinal morphometry was used to assess villus length, crypt length, and mitotic crypt count. Immunohistochemistry of p53, nuclear factor-B, cyclooxygenase (COX)-1, and COX-2 was also done. The fractionated radiotherapy course induced alimentary mucositis from week 1, with more severe injury seen in the small intestine. The hallmark appearance of apoptosis was present in the crypts of the small and large intestine. In the jejunum and colon, goblet cell disorganization and degeneration was obvious and crypt mitotic counts were severely depleted throughout the treatment. Expression of p53, nuclear factor-B, COX-1, and COX-2 was increased in the irradiated intestinal sections. Fractionated radiation-induced alimentary mucositis has been effectively documented in the Dark Agouti rat for the first time. Further studies investigating the molecular mechanisms underlying radiation-induced mucositis are planned to ultimately achieve anti-mucotoxic-targeted therapies. Mol Cancer Ther 2007; 6(8):2319-27
Purpose
The aim of this project was to review the available literature and define clinical practice guidelines for the use of anti-inflammatory agents for the prevention and treatment of oral ...mucositis in cancer patients.
Materials and methods
A systematic review was conducted by the Mucositis Study Group of the Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology. The body of evidence for use of each intervention, in each cancer treatment setting, was assigned an evidence level. Based on the evidence level, one of the following three guideline determinations was possible: recommendation, suggestion, and no guideline possible.
Results
Forty-one papers were reviewed. There was sufficient evidence to recommend the use of benzydamine mouthwash for the prevention of oral mucositis in head and neck cancer patients receiving moderate-dose radiation therapy (up to 50 Gy), without concomitant chemotherapy. A new suggestion was developed against the use of misoprostol mouthwash for the prevention of oral mucositis in head and neck cancer patients receiving radiation therapy. Positive results were reported for some other anti-inflammatory agents. However, no guidelines were able to be developed for any other agents due to insufficient and/or conflicting evidence.
Conclusions
The use of anti-inflammatory agents continues to be a promising strategy for the prevention and treatment of oral mucositis. Additional well-designed studies are needed to examine the use of this class of agents for oral mucositis.
We estimate that there will be 13·7 million new cases of childhood cancer globally between 2020 and 2050. At current levels of health system performance (including access and referral), 6·1 million ...(44·9%) of these children will be undiagnosed. Between 2020 and 2050, 11·1 million children will die from cancer if no additional investments are made to improve access to health-care services or childhood cancer treatment. Of this total, 9·3 million children (84·1%) will be in low-income and lower-middle-income countries. This burden could be vastly reduced with new funding to scale up cost-effective interventions. Simultaneous comprehensive scale-up of interventions could avert 6·2 million deaths in children with cancer in this period, more than half (56·1%) of the total number of deaths otherwise projected. Taking excess mortality risk into consideration, this reduction in the number of deaths is projected to produce a gain of 318 million life-years. In addition, the global lifetime productivity gains of US$2580 billion in 2020–50 would be four times greater than the cumulative treatment costs of $594 billion, producing a net benefit of $1986 billion on the global investment: a net return of $3 for every $1 invested. In sum, the burden of childhood cancer, which has been grossly underestimated in the past, can be effectively diminished to realise massive health and economic benefits and to avert millions of needless deaths.
Purpose: To evaluate prospectively the prevalence and pathophysiology of anorectal dysfunction following radiation therapy (RTH) for localized carcinoma of the prostate.
Methods and Materials: The ...following parameters of anorectal function were evaluated in each of 35 patients (aged 55–82 years) with localized prostatic carcinoma treated with RTH either to a dose of 55 Gy/20 fractions/4 weeks (18 patients) or 64 Gy/32 fractions/6.5 weeks (17 patients), before RTH and 4–6 weeks and at a mean (± SD) of 1.4 (± 0.2) years after its completion: (
1) anorectal symptoms (questionnaire), (
2) anorectal pressures at rest and in response to voluntary squeeze and increases in intra-abdominal pressure (multiport anorectal manometry), (
3) rectal sensation (balloon distension) and (
4) anal sphincteric morphology (endoanal ultrasound).
Results: All but 1 patient completed three series of measurements. RTH had no effect on anal sphincteric morphology. The increase in frequency of defecation and fecal urgency and incontinence scores previously reported in the patients 4–6 weeks after RTH were sustained 1 year later (
p < 0.001,
p < 0.001, and
p < 0.05, cf. baseline, respectively). At this time, 56% (19 of 34), 50% (17 of 34) and 26% (9 of 34) of the patients had increased frequency of defecation, fecal urgency, and incontinence, respectively. Decreases in anal sphincteric pressures at rest and in response to voluntary squeeze recorded in the patients 4–6 weeks after RTH were not sustained 1 year later but the volumes of rectal distension associated with perception of the stimulus and desire to defecate were lower compared with baseline volumes (
p < 0.01 and
p < 0.05, respectively), reflecting heightened rectal sensitivity in the patients. There was no difference in measurements between the two radiation dose regimens. Univariate logistical regression analysis was performed on patients who had experienced increased symptom scores or decreases in recorded motor and sensory manometric parameters at 1 year, cf. baseline. The predictor variables used included individual patient tumor and treatment characteristics as well as individual patient symptom scores and parameters of anorectal motor and sensory function at baseline and 4–6 weeks after RTH. The results of the univariate logistical regression analysis showed that (
1) frequency of defecation at 4–6 weeks and (
2) rectal volumes at baseline both for (
a) perception (
p < 0.001) and (
b) desire to defecate (
p < 0.001), predicted significantly for the patients who had symptoms and signs of anorectal dysfunction at 1 year. Individual patient tumor and treatment-related variables tested, in contrast, had no predictive significance.
Conclusions: Anorectal symptoms following RTH for prostatic carcinoma are common and persist at least until 1 year after its completion and are associated with objective evidence of heightened rectal sensitivity.
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