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Purpose: In AAPM Task Group 204, the size-specific dose estimate (SSDE) was developed by providing size adjustment factors which are applied to the Computed Tomography (CT) standardized dose metric, CTDI vol . However, that work focused on fixed tube current scans and did not specifically address tube current modulation (TCM) scans, which are currently the majority of clinical scans performed. The purpose of this study was to extend the SSDE concept to account for TCM by investigating the feasibility of using anatomic and organ specific regions of scanner output to improve accuracy of dose estimates. Methods: Thirty-nine adult abdomen/pelvis and 32 chest scans from clinically indicated CT exams acquired on a multidetector CT using TCM were obtained with Institutional Review Board approval for generating voxelized models. Along with image data, raw projection data were obtained to extract TCM functions for use in Monte Carlo simulations. Patient size was calculated using the effective diameter described in TG 204. In addition, the scanner-reported CTDI vol (CTDI vol,global ) was obtained for each patient, which is based on the average tube current across the entire scan. For the abdomen/pelvis scans, liver, spleen, and kidneys were manually segmented from the patient datasets; for the chest scans, lungs and for female models only, glandular breast tissue were segmented. For each patient organ doses were estimated using Monte Carlo Methods. To investigate the utility of regional measures of scanner output, regional and organ anatomic boundaries were identified from image data and used to calculate regional and organ-specific average tube current values. From these regional and organ-specific averages, CTDI vol values, referred to as regional and organ-specific CTDI vol , were calculated for each patient. Using an approach similar to TG 204, all CTDI vol values were used to normalize simulated organ doses; and the ability of each normalized dose to correlate with patient size was investigated. Results: For all five organs, the correlations with patient size increased when organ doses were normalized by regional and organ-specific CTDI vol values. For example, when estimating dose to the liver, CTDI vol,global yielded a R 2 value of 0.26, which improved to 0.77 and 0.86, when using the regional and organ-specific CTDI vol for abdomen and liver, respectively. For breast dose, the global CTDI vol yielded a R 2 value of 0.08, which improved to 0.58 and 0.83, when using the regional and organ-specific CTDI vol for chest and breasts, respectively. The R 2 values also increased once the thoracic models were separated for the analysis into females and males, indicating differences between genders in this region not explained by a simple measure of effective diameter. Conclusions: This work demonstrated the utility of regional and organ-specific CTDI vol as normalization factors when using TCM. It was demonstrated that CTDI vol,global is not an effective normalization factor in TCM exams where attenuation (and therefore tu...

BackgroundData from the California Health Interview Survey (CHIS) indicate that levels and temporal trends in colorectal cancer (CRC) screening prevalence vary among Asian American groups; however, the reasons for these differences have not been fully investigated.MethodsUsing CHIS 2001, 2003 and 2005 data, we conducted hierarchical regression analyses progressively controlling for demographic characteristics, English proficiency and access to care in an attempt to identify factors explaining differences in screening prevalence and trends among Chinese, Filipino, Vietnamese, Korean and Japanese Americans (N = 4,188).ResultsAfter controlling for differences in gender and age, all Asian subgroups had significantly lower odds of having ever received screening in 2001 than the reference group of Japanese Americans. In addition, Korean Americans were the only subgroup that had a statistically significant decline in screening prevalence from 2001 to 2005 compared to the trend among Japanese Americans. After controlling for differences in education, marital status, employment status and federal poverty level, Korean Americans were the only group that had significantly lower screening prevalence than Japanese Americans in 2001, and their trend to 2005 remained significantly depressed. After controlling for differences in English proficiency and access to care, screening prevalences in 2001 were no longer significantly different among the Asian subgroups, but the trend among Korean Americans from 2001 to 2005 remained significantly depressed. Korean and Vietnamese Americans were less likely than other groups to report a recent doctor recommendation for screening and more likely to cite a lack of health problems as a reason for not obtaining screening.ConclusionsDifferences in CRC screening trends among Asian ethnic groups are not entirely explained by differences in demographic characteristics, English proficiency and access to care. A better understanding of mutable factors such as rates of doctor recommendation and health beliefs will be crucial for designing culturally appropriate interventions to promote CRC screening.

ObjectivesTo propose and evaluate a technique for automatic quantification of fissural completeness from chest computed tomography (CT) in a database of subjects with severe emphysema.MethodsNinety-six CT studies of patients with severe emphysema were included. The lungs, fissures and lobes were automatically segmented. The completeness of the fissures was calculated as the percentage of the lobar border defined by a fissure. The completeness score of the automatic method was compared with a visual consensus read by three radiologists using boxplots, rank sum tests and ROC analysis.ResultsThe consensus read found 49% (47/96), 15% (14/96) and 67% (64/96) of the right major, right minor and left major fissures to be complete. For all fissures visually assessed as being complete the automatic method resulted in significantly higher completeness scores (mean 92.78%) than for those assessed as being partial or absent (mean 77.16%; all p values <0.001). The areas under the curves for the automatic fissural completeness were 0.88, 0.91 and 0.83 for the right major, right minor and left major fissures respectively.ConclusionsAn automatic method is able to quantify fissural completeness in a cohort of subjects with severe emphysema consistent with a visual consensus read of three radiologists.Key Points• Lobar fissures are important for assessing the extent and distribution of lung disease• Modern CT allows automatic lobar segmentation and assessment of the fissures• This segmentation can also assess the completeness of the fissures.• Such assessment is important for decisions about novel therapies (eg for emphysema).

Introduction This study examined the association between sociodemographic, cancer treatment, and care delivery factors on young adult cancer survivors’ confidence in managing their survivorship care. Methods Survivors aged 18-39 years (n=376) recruited from the LIVESTRONG™ Survivorship Center of Excellence Network sites completed a survey assessing self-reported receipt of survivorship care planning, expectations of their providers, and confidence in managing their survivorship care. Multivariate logistic regression identified characteristics of those reporting low confidence in managing their survivorship care. Results Mean age was 28 years; mean interval from diagnosis was 9 ± 8 years. Seventy-one percent reported currently attending an oncology survivorship clinic. Regarding survivorship care planning, 33% did not have copies of their cancer-related medical records, 48% did not have a treatment summary, and 55% had not received a survivorship care plan. Seventy percent identified the oncologist as the most important health care provider for decisions regarding test and treatment decisions, while 10% reported using a “shared-care model” involving both primary care providers and oncologists. Forty-one percent were classified as having low confidence in managing survivorship care. In multivariate analysis, low confidence was associated with non-white ethnicity and lack of a survivorship care plan (both p<.05). Discussion/Conclusion Findings suggest that provision of survivorship care plans for young adult cancer survivors can be used to improve confidence in managing survivorship care, particularly for ethnic minorities. Implications for Cancer Survivors Survivors should consider advocating for receipt of a survivorship care plan as it may facilitate confidence as a consumer of survivorship care.