Intensity-modulated radiation therapy (IMRT) has become the mainstay of treatment for localized prostate cancer. In IMRT, minimizing differences between the conditions used during planning CT and daily treatment is im...Intensity-modulated radiation therapy (IMRT) has become the mainstay of treatment for localized prostate cancer. In IMRT, minimizing differences between the conditions used during planning CT and daily treatment is important to prevent adverse events in normal tissues. In the present study, we evaluated the impact of variation in bladder volume on the doses to various organs. A total of 35 patients underwent definitive radiotherapy at Saitama Medical Center. A Light Speed RT16 (GE Healthcare) was used for planning and to obtain examination CT images. Such images were acquired after 4 - 6 days of planning CT image acquisition. The IMRT plans were optimized using the planning CT data to satisfy the dose constraints set by our in-house protocols for the PTV and the OARs. The dose distributions were then re-calculated using the same IMRT beams, and checked on examination CT images. It was clear that bladder volume affected the doses to certain organs. We focused on the prostate, bladder, rectum, small bowel, and large bowel. Regression coefficients were calculated for variables that correlated strongly with bladder volume (p < 0.05). We found that variation in bladder volume [cm<sup>3</sup>] predicted deviations in the bladder V<sub>70Gy</sub>, V<sub>50Gy</sub>, and V<sub>30Gy</sub> [%];the maximum dose to the small bowel [cGy];and the maximum dose to the large bowel [cGy]. The regression coefficients were -0.065, -0.125, -0.180, -10.22, and -9.831, respectively. We evaluated the impacts of such variation on organ doses. These may be helpful when checking a patient’s bladder volume before daily IMRT for localized prostate cancer.展开更多
This study aimed to investigate the impact of artificial intelligence-assisted intensity-modulated radiotherapy(IMRT)plan optimization on the radiation doses received by the rectum and bladder as well as radiation-ind...This study aimed to investigate the impact of artificial intelligence-assisted intensity-modulated radiotherapy(IMRT)plan optimization on the radiation doses received by the rectum and bladder as well as radiation-induced injuries in patients with locally advanced cervical cancer.A total of 100 patients with locally advanced cervical cancer were enrolled and divided into a conventional IMRT group and an artificial intelligence-assisted IMRT group.The results showed that in terms of the radiation doses to the rectum and bladder,all dosimetric parameters(such as mean dose,maximum dose,and volume-dose parameters,etc.)in the artificial intelligence-assisted group were significantly lower than those in the conventional group(p<0.05).Regarding radiation-induced injuries,the incidences and severities of both acute and late radiation-induced proctitis and cystitis in the artificial intelligence-assisted group were lower than those in the conventional group(p<0.05).These findings suggest that artificial intelligence-assisted IMRT plan optimization can effectively reduce the radiation doses to the rectum and bladder and decrease radiation-induced injuries in patients with locally advanced cervical cancer,which is expected to provide a more precise and safer treatment strategy for radiotherapy of locally advanced cervical cancer.However,this study has limitations such as a limited sample size and being a single-center study.Future research with multi-center,large-sample,and more in-depth investigations is needed.展开更多
Objective Analyses of bladder cancer mortality in the Black Foot Disease (BFD) endemic area of southwest Taiwan conducted by Morales et al. showed a discontinuity in risk at 400μg/L arsenic in the drinking water in a...Objective Analyses of bladder cancer mortality in the Black Foot Disease (BFD) endemic area of southwest Taiwan conducted by Morales et al. showed a discontinuity in risk at 400μg/L arsenic in the drinking water in a stratified analysis and no discontinuity in a continuous analysis. As the continuous analysis presentation had been used by both the NRC and the EPA to assess the carcinogenic risk from arsenic ingestion, an explanation of the discontinuity was sought. Methods Review of 40 years of published health studies of the BFD-endemic area of SW Taiwan showed that earlier publications had limited their cancer associations with arsenic levels in artesian well waters and that the reports of Morales et al., NRC, and EPA failed to do so. Underlying data for the Morales et al. study were obtained from the appendix to the NRC report. Bladder cancer mortality rates were calculated from case counts and person-years of observation for each study village. Villages were categorized by water source according to the descriptions from the underlying study. Graphic and regression analyses were conducted of the bladder cancer mortality rates using exposure as a continuous variable and simultaneously stratifying by water source. Results The median village well arsenic levels ranged from 350 to 934μg/L for villages solely dependent on artesian well water and from 10 to 717μg/L for villages not solely dependent on artesian well water. Bladder cancer mortality rates were found to be dependent upon the arsenic level only for those villages that were solely dependent on artesian well water for their water source. Bladder cancer mortality rates were found to be independent of arsenic level for villages with non-artesian well water sources. Conclusions The data indicate that arsenic exposure levels do not explain the bladder cancer mortality risk in SW Taiwan among villages not dependent upon artesian well water. The association for villages dependent upon artesian well water may be explained either by arsenic acting as a high-dose carcinogen or in artesian well water as a co-carcinogen with some other aspect of artesian well water (possibly humic acid). Arsenic exposure level alone appears to be an insufficient exposure measure to describe the risk of bladder cancer mortality in the BFD-endemic area. Risk analyses that fail to take water source into account are likely to misrepresent the risk characterization, particularly at low arsenic levels.展开更多
Aim: To explore in daily clinical practice the evolution in time of the fesoterodine and solifenacin dose pattern and assess the therapeutic benefit provided by the highest dose of these anti-muscarinics. Patients and...Aim: To explore in daily clinical practice the evolution in time of the fesoterodine and solifenacin dose pattern and assess the therapeutic benefit provided by the highest dose of these anti-muscarinics. Patients and Methods: This was a post-hoc analysis of data from an observational, cross-sectional, retrospective and multicenter study. Adult patients diagnosed with over active bladder (OAB) who initiated fesoterodine or solifenacin treatment were included. Data on the prescribed treatment and dose, change of dose, reasons for switching and treatment benefit were recorded. Results: A total of 828 subjects were analyzed (262 receiving solifenacin and 566 fesoterodine). Most subjects were women with a mean time since diagnosis of more than one year and aged around 60 years old. The majority of patients initiated the OAB treatment with the lowest available dose (64% fesoterodine vs. 77% solifenacin). At the follow-up visit 54% of the fesoterodine group and 66% of the solifenacin opted for dose escalation. At the study visit, 70.1% fesoterodine vs. 43.3% solifenacin remained on the highest dose. A significantly greater proportion of subjects receiving fesoterodine 8 mg, reported higher improvement in terms of both patient-reported-treatment benefit and clinical global impression compared with solifenacin 10 mg (p < 0.05). Conclusion: In routine clinical practice more than half of the patients opted for the higher dose and remained on it over time, suggesting a desire for greater efficacy. Fesoterodine 8 mg seems to provide greater benefits from the physician’s and the patient’s point of view compared with those provided by solifenacin 10 mg.展开更多
文摘Intensity-modulated radiation therapy (IMRT) has become the mainstay of treatment for localized prostate cancer. In IMRT, minimizing differences between the conditions used during planning CT and daily treatment is important to prevent adverse events in normal tissues. In the present study, we evaluated the impact of variation in bladder volume on the doses to various organs. A total of 35 patients underwent definitive radiotherapy at Saitama Medical Center. A Light Speed RT16 (GE Healthcare) was used for planning and to obtain examination CT images. Such images were acquired after 4 - 6 days of planning CT image acquisition. The IMRT plans were optimized using the planning CT data to satisfy the dose constraints set by our in-house protocols for the PTV and the OARs. The dose distributions were then re-calculated using the same IMRT beams, and checked on examination CT images. It was clear that bladder volume affected the doses to certain organs. We focused on the prostate, bladder, rectum, small bowel, and large bowel. Regression coefficients were calculated for variables that correlated strongly with bladder volume (p < 0.05). We found that variation in bladder volume [cm<sup>3</sup>] predicted deviations in the bladder V<sub>70Gy</sub>, V<sub>50Gy</sub>, and V<sub>30Gy</sub> [%];the maximum dose to the small bowel [cGy];and the maximum dose to the large bowel [cGy]. The regression coefficients were -0.065, -0.125, -0.180, -10.22, and -9.831, respectively. We evaluated the impacts of such variation on organ doses. These may be helpful when checking a patient’s bladder volume before daily IMRT for localized prostate cancer.
文摘This study aimed to investigate the impact of artificial intelligence-assisted intensity-modulated radiotherapy(IMRT)plan optimization on the radiation doses received by the rectum and bladder as well as radiation-induced injuries in patients with locally advanced cervical cancer.A total of 100 patients with locally advanced cervical cancer were enrolled and divided into a conventional IMRT group and an artificial intelligence-assisted IMRT group.The results showed that in terms of the radiation doses to the rectum and bladder,all dosimetric parameters(such as mean dose,maximum dose,and volume-dose parameters,etc.)in the artificial intelligence-assisted group were significantly lower than those in the conventional group(p<0.05).Regarding radiation-induced injuries,the incidences and severities of both acute and late radiation-induced proctitis and cystitis in the artificial intelligence-assisted group were lower than those in the conventional group(p<0.05).These findings suggest that artificial intelligence-assisted IMRT plan optimization can effectively reduce the radiation doses to the rectum and bladder and decrease radiation-induced injuries in patients with locally advanced cervical cancer,which is expected to provide a more precise and safer treatment strategy for radiotherapy of locally advanced cervical cancer.However,this study has limitations such as a limited sample size and being a single-center study.Future research with multi-center,large-sample,and more in-depth investigations is needed.
文摘Objective Analyses of bladder cancer mortality in the Black Foot Disease (BFD) endemic area of southwest Taiwan conducted by Morales et al. showed a discontinuity in risk at 400μg/L arsenic in the drinking water in a stratified analysis and no discontinuity in a continuous analysis. As the continuous analysis presentation had been used by both the NRC and the EPA to assess the carcinogenic risk from arsenic ingestion, an explanation of the discontinuity was sought. Methods Review of 40 years of published health studies of the BFD-endemic area of SW Taiwan showed that earlier publications had limited their cancer associations with arsenic levels in artesian well waters and that the reports of Morales et al., NRC, and EPA failed to do so. Underlying data for the Morales et al. study were obtained from the appendix to the NRC report. Bladder cancer mortality rates were calculated from case counts and person-years of observation for each study village. Villages were categorized by water source according to the descriptions from the underlying study. Graphic and regression analyses were conducted of the bladder cancer mortality rates using exposure as a continuous variable and simultaneously stratifying by water source. Results The median village well arsenic levels ranged from 350 to 934μg/L for villages solely dependent on artesian well water and from 10 to 717μg/L for villages not solely dependent on artesian well water. Bladder cancer mortality rates were found to be dependent upon the arsenic level only for those villages that were solely dependent on artesian well water for their water source. Bladder cancer mortality rates were found to be independent of arsenic level for villages with non-artesian well water sources. Conclusions The data indicate that arsenic exposure levels do not explain the bladder cancer mortality risk in SW Taiwan among villages not dependent upon artesian well water. The association for villages dependent upon artesian well water may be explained either by arsenic acting as a high-dose carcinogen or in artesian well water as a co-carcinogen with some other aspect of artesian well water (possibly humic acid). Arsenic exposure level alone appears to be an insufficient exposure measure to describe the risk of bladder cancer mortality in the BFD-endemic area. Risk analyses that fail to take water source into account are likely to misrepresent the risk characterization, particularly at low arsenic levels.
文摘Aim: To explore in daily clinical practice the evolution in time of the fesoterodine and solifenacin dose pattern and assess the therapeutic benefit provided by the highest dose of these anti-muscarinics. Patients and Methods: This was a post-hoc analysis of data from an observational, cross-sectional, retrospective and multicenter study. Adult patients diagnosed with over active bladder (OAB) who initiated fesoterodine or solifenacin treatment were included. Data on the prescribed treatment and dose, change of dose, reasons for switching and treatment benefit were recorded. Results: A total of 828 subjects were analyzed (262 receiving solifenacin and 566 fesoterodine). Most subjects were women with a mean time since diagnosis of more than one year and aged around 60 years old. The majority of patients initiated the OAB treatment with the lowest available dose (64% fesoterodine vs. 77% solifenacin). At the follow-up visit 54% of the fesoterodine group and 66% of the solifenacin opted for dose escalation. At the study visit, 70.1% fesoterodine vs. 43.3% solifenacin remained on the highest dose. A significantly greater proportion of subjects receiving fesoterodine 8 mg, reported higher improvement in terms of both patient-reported-treatment benefit and clinical global impression compared with solifenacin 10 mg (p < 0.05). Conclusion: In routine clinical practice more than half of the patients opted for the higher dose and remained on it over time, suggesting a desire for greater efficacy. Fesoterodine 8 mg seems to provide greater benefits from the physician’s and the patient’s point of view compared with those provided by solifenacin 10 mg.
