Kimberly R. Porter
Kaiser Permanente
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Featured researches published by Kimberly R. Porter.
Neuro-oncology | 2010
Kimberly R. Porter; Bridget J. McCarthy; Sally Freels; Yoonsang Kim; Faith G. Davis
Prevalence is the best indicator of cancer survivorship in the population, but few studies have focused on brain tumor prevalence because of previous data limitations. Hence, the full impact of primary brain tumors on the healthcare system in the United States is not completely described. The present study provides an estimate of the prevalence of disease in the United States, updating an earlier prevalence study. Incidence data for 2004 and survival data for 1985-2005 were obtained by the Central Brain Tumor Registry of the United States from selected regions, modeled under 2 different survival assumptions, to estimate prevalence rates for the year 2004 and projected estimates for 2010. The overall incidence rate for primary brain tumors was 18.1 per 100 000 person-years with 2-, 5-, 10-, and 20-year observed survival rates of 62%, 54%, 45%, and 30%, respectively. On the basis of the sum of nonmalignant and averaged malignant estimates, the overall prevalence rate of individuals with a brain tumor was estimated to be 209.0 per 100 000 in 2004 and 221.8 per 100 000 in 2010. The female prevalence rate (264.8 per 100 000) was higher than that in males (158.7 per 100 000). The averaged prevalence rate for malignant tumors (42.5 per 100 000) was lower than the prevalence for nonmalignant tumors (166.5 per 100 000). This study provides estimates of the 2004 (n = 612 770) and 2010 (n = 688 096) expected number of individuals living with primary brain tumor diagnoses in the United States, providing more current and robust estimates for aiding healthcare planning and patient advocacy for an aging US population.
BJUI | 2013
Chun Chao; Steven J. Jacobsen; Lanfang Xu; Lauren P. Wallner; Kimberly R. Porter; Stephen G. Williams
Statins have shown broad spectrum anti‐cancer properties in laboratory studies. In epidemiological studies, use of statins has been associated with reduced risk of advanced prostate cancer. However, the effects of statins on prostate cancer disease progression following curative treatment have not been extensively studied, and previous studies reported conflicting results. This study found no clear association between overall statin use and risk of disease progression, as well as lack of a monotone dose–response relationship between the use of statins, whether it was use before or after prostatectomy, and prostate cancer disease progression.
Neuroepidemiology | 2011
Kimberly R. Porter; Bridget J. McCarthy; Michael L. Berbaum; Faith G. Davis
Background: Survival statistics commonly reflect survival from the time of diagnosis but do not take into account survival already achieved after a diagnosis. The objective of this study was to provide conditional survival estimates for brain tumor patients as a more accurate measure of survival for those who have already survived for a specified amount of time after diagnosis. Methods: Data on primary malignant and nonmalignant brain tumor cases diagnosed from 1985–2005 from selected SEER state cancer registries were obtained. Relative survival up to 15 years postdiagnosis and varying relative conditional survival rates were computed using the life-table method. Results: The overall 1-year relative survival estimate derived from time of diagnosis was 67.8% compared to the 6-month relative conditional survival rate of 85.7% for 6-month survivors (the probability of surviving to 1 year given survival to 6 months). The 10-year overall relative survival rate was 49.5% from time of diagnosis compared to the 8-year relative conditional survival rate of 79.2% for 2-year survivors. Conditional survival estimates and standard survival estimates varied by histology, behavior, and age at diagnosis. The 5-year relative survival estimate derived from time of diagnosis for glioblastoma was 3.6% compared to the 3-year relative conditional survival rate of 36.4% for 2-year survivors. For most nonmalignant tumors, the difference between relative survival and the corresponding conditional survival estimates were minimal. Older age groups had greater numeric gains in survival but lower conditional survival estimates than other age groups. Similar findings were seen for other conditional survival intervals. Conclusions: Conditional survival is a useful disease surveillance measure for clinicians and brain tumor survivors to provide them with better ‘real-time’ estimates and hope.
Cancer Letters | 2013
Chun Chao; Stephen G. Williams; Lanfang Xu; Jergin Chen; Lauren P. Wallner; Kimberly R. Porter; Steven J. Jacobsen
We investigated whether statin use is associated with reduced risk of recurrence in prostate cancer patients who undergo radiotherapy. A retrospective cohort of 774 patients from a California health plan was followed for 5 years. Statin use prior to, during and after radiotherapy was not associated with prostate cancer recurrence [hazard ratio=0.99 (0.70-1.39), 0.87 (0.62-1.22) and 0.78 (0.55-1.09), respectively] in multivariable Cox models. No clear dose-response relationship was observed for average daily statin dose or duration of statin use. Our findings do not support a preventive benefit of statins in prostate cancer recurrence after radiotherapy.
Annals of Epidemiology | 2014
Kimberly R. Porter; Chun Chao; Virginia P. Quinn; Jin-Wen Y. Hsu; Steven J. Jacobsen
PURPOSE The date of cancer diagnosis is a critical data element for clinical care and research. Because this date can be abstracted from various data sources, its comparability from source to source is unclear. This study compared the date of diagnosis from multiple sources within the same population of prostate cancer patients. METHODS We linked cancer registry, pathology report, and electronic health data sources from the Kaiser Permanente Southern California health data systems for a cohort of 22,666 members diagnosed with prostate cancer between 2000 and 2010. The magnitude and direction of the differences in date of diagnosis were assessed for each date pairwise comparison. We reviewed 454 medical records to determine reasons for date discrepancies. RESULTS Among the date pairwise comparisons, differences in date of diagnosis spanned from 9.6 years earlier to 10 years later than each other. However, the overall median difference ranged from 1 to 16 days, thus suggesting that the vast majority of the date differences were small. Chart review results identified major categories of date discrepancies. CONCLUSIONS These data demonstrate variability in date of diagnosis across these data sources. This variability may have implications for epidemiologic estimates or patient identification in research studies using different data sources.
Urology | 2013
Kimberly R. Porter; Jin-Wen Y. Hsu; Gary W. Chien; Anny H. Xiang; Howard Jung; Chun Chao; Steven J. Jacobsen
OBJECTIVE To investigate the racial/ethnic differences in the time to treatment among patients with prostate cancer. MATERIALS AND METHODS All 3448 men diagnosed with localized prostate cancer at Kaiser Permanente Southern California from 2006 to 2007 were identified. The patients were passively followed up through their electronic health records until definitive treatment, defined as the first treatment given with curative intent within 1 year of diagnosis. Cox proportional hazard models, with PROC SURVEYPHREG procedures, were used to account for the variability in time to the different treatments within multiple medical centers. RESULTS The overall median time to treatment was 102 days, with modest differences for whites (100 days), blacks (104 days), and Hispanics (99 days). In the adjusted model, black men had a significantly longer time to surgery (adjusted hazard ratio 0.74, 95% confidence interval 0.56-0.91) compared with white men. Hispanic men (adjusted hazard ratio 1.44, 95% confidence interval 1.07-1.74) experienced significantly shorter times to radiotherapy compared with white men. No difference was found in the time to radiotherapy or brachytherapy for black men relative to white men. CONCLUSION These data suggest that minimal racial/ethnic differences exist in the time to treatment after the diagnosis of prostate cancer in this equal-access setting. This is encouraging, but does not mean that all men were satisfied with their treatment choice.
Sexual Medicine | 2017
Stephanie R. Reading; Kimberly R. Porter; J.M. Slezak; Teresa N. Harrison; Joy Gelfond; Gary W. Chien; Steven J. Jacobsen
Introduction Many men diagnosed with prostate cancer are concerned with how the disease and its course of treatment could affect their health-related quality of life (HRQOL). To aid in the decision-making process on a course of treatment and to better understand how these treatments can affect HRQOL, knowledge of pretreatment HRQOL is essential. Aims To assess the racial and ethnic variations in HRQOL scores in men newly diagnosed with prostate cancer before electing a course of treatment. Methods Male members of the Kaiser Permanente of Southern California health plan who were newly diagnosed with prostate cancer completed the five-domain specific Expanded Prostate Index Composite–26 (EPIC-26) HRQOL questionnaire from March 1, 2011 through August 31, 2013 (N = 2,579). Domain scores were compared across racial and ethnic subgroups and multiple logistic regression analyses were used to assess the association after adjusting for sociodemographic and clinical characteristics. Main Outcome Measures The five EPIC-26 domain scores (sexual, bowel, hormonal, urinary incontinence, and urinary irritation and obstruction). Results Results from the fully adjusted analyses indicated that non-Hispanic black men were more likely to be above the sample median on the sexual (odds ratio [OR] = 1.43, 95% CI = 1.09–1.88), hormonal (OR = 1.35, 95% CI = 1.03–1.77), and urinary irritation and obstruction (OR = 1.34, 95% CI = 1.03–1.74) domains compared with non-Hispanic white men. The Asian or Pacific Islander men were less likely to be above the sample median on the sexual domain (OR = 0.60, 95% CI = 0.44–0.83) compared with non-Hispanic white men. No additional statistically significant differences were identified. Conclusions Within an integrated health care organization, we found minimal racial and ethnic differences, aside from sexual function, in pretreatment HRQOL in men newly diagnosed with prostate cancer. These findings provide important insight with which to interpret HRQOL changes in men newly diagnosed with prostate cancer during and after prostate cancer treatment. Reading SR, Porter KR, Slezak JM, et al. Racial and Ethnic Variation in Health-Related Quality of Life Scores Prior to Prostate Cancer Treatment. Sex Med 2017;5:e219–e228.
Urology | 2016
Stephanie R. Reading; Kimberly R. Porter; Jin Wen Y Hsu; Lauren P. Wallner; Ronald K. Loo; Steven J. Jacobsen
OBJECTIVE To examine the racial and ethnic variation in time to prostate biopsy after an elevated screening level of serum prostate-specific antigen (PSA). METHODS Male members of the Kaiser Permanente of Southern California health plan, 45 years of age or older, with no history of prostate cancer or a prostate biopsy, and at least 1 elevated screening level of serum PSA between January 1, 1998 and December 31, 2007 were retrospectively identified (n = 59,506). All participants were passively followed via electronic health records until their time of prostate biopsy, death, membership disenrollment, or study conclusion (December 31, 2014), whichever was the initial event. Proportional hazard regression analyses were used to estimate the association between time from an elevated screening level of serum PSA to prostate biopsy, adjusting for age, benign prostatic hyperplasia, prostatitis, type 2 diabetes mellitus, hypertension, and Charlson Comorbidity Index score. RESULTS Median time until biopsy was 0.6 years (214 days), with approximately 41% of participants receiving a prostate biopsy within the study period. Results from the fully adjusted analysis indicated that the non-Hispanic Asian or Pacific Islanders (hazard ratio: 1.10, 95% confidence interval: [1.04, 1.15]) and the non-Hispanic blacks (hazard ratio: 1.04, 95% confidence interval: [1.00, 1.08]) had a slightly shorter time to prostate biopsy after an elevated screening level of serum PSA compared to the non-Hispanic whites. CONCLUSION These data suggest that, within an integrated healthcare organization, minimal differences exist between racial and ethnic subgroups in their time to prostate biopsy after an elevated screening level of serum PSA.
Journal of Clinical Oncology | 2016
Stephanie R. Reading; Kimberly R. Porter; Jeffrey M. Slezak; Gary W. Chien; Steven J. Jacobsen
232 Background: To compare the racial and ethnic variations in baseline health-related quality of life (HRQOL) scores among men newly-diagnosed with prostate cancer prior to their prostate cancer treatment. METHODS Male members of the Kaiser Permanente of Southern California (KPSC) health plan, newly-diagnosed with prostate cancer, completed the five-domain specific Expanded Prostate Index Composite (EPIC-26) health-related quality of life (HRQOL) questionnaire between March 1, 2011 and August 31, 2013 (n=2,225). The five EPIC-26 domain scores (sexual, bowel, hormonal, urinary incontinence and urinary irritation) were compared across racial and ethnic subgroups and multiple logistic regression analyses were used to assess the association, adjusting for socio-demographic and clinical characteristics. RESULTS Within each racial and ethnic subgroup,higher baseline HRQOL scores were seen on the bowel, hormonal, urinary incontinence and urinary irritation domains (median score range: 87.5 - 100) as compared to the sexual domain (median score range: 49.3 - 62.5). Asian or Pacific Islander men were less likely to be above the sample median on the sexual (OR=0.51; 95% CI [0.36, 0.74]; p<0.001) and urinary incontinence domains (OR=0.65; 95% CI [0.46, 0.92]; p=0.015) as compared to the non-Hispanic white men. No additional statistically significant differences (p<0.05) were identified. CONCLUSIONS These data suggest that few differences exist in baseline HRQOL scores across racial and ethnic subgroups among men newly-diagnosed with prostate cancer in an integrated health care organization. This finding provides important insight into the pre-treatment HRQOL status among these men with which to interpret HRQOL changes during and after prostate cancer treatment.
Supportive Care in Cancer | 2014
Kimberly R. Porter; Usha Menon; Nicholas A. Vick; John L. Villano; Michael L. Berbaum; Faith G. Davis