Biomedical subjects

Charles R Key

Publications and source records attributed to Charles R Key.

5 recordsLinked to original sources

PubMed2003

Discrepancy between consensus recommendations and actual community use of adjuvant chemotherapy in women with breast cancer.

BACKGROUND: Although the efficacy of adjuvant chemotherapy in prolonging survival for women with breast cancer has been well documented, limited population-based information is available on the actual use of chemotherapy. OBJECTIVE: To examine the relationship between age and chemotherapy use. DESIGN: Cohort study. SETTING: New Mexico. PATIENTS: 5101 women 20 years of age or older receiving a diagnosis of stage I, stage II, or stage IIIA breast cancer from 1991 through 1997. MEASUREMENTS: Pattern of chemotherapy use by age; logistic regression analysis to generate the odds and probabilities of receiving chemotherapy; and sensitivity analysis to estimate potential effects of unmeasured confounders. RESULTS: Overall, 29% of women received chemotherapy. The rate of chemotherapy use for women with stage I, stage II, or stage IIIA breast cancer was 11%, 47%, and 68%, respectively. Across all tumor stages, the use of chemotherapy decreased substantially with increasing age (P < 0.001). Overall, 66% of women younger than 45 years of age received chemotherapy compared with 44% of women between 50 and 54 years of age, 31% of women between 55 and 59 years of age, and 18% of women between 60 and 64 years of age. The decreasing pattern of chemotherapy use with age continued after adjustment for prognostic factors and was relatively insensitive to changes in unmeasured factors. CONCLUSIONS: There is considerable discrepancy between the 1990 National Institutes of Health Consensus Conference recommendations for chemotherapy administration in women with breast cancer and the actual use of chemotherapy in the community. The decrease in use with age may relate to the decreasing efficacy of chemotherapy with age, as reported in clinical trials. Outcomes studies should address whether the recommendations are overly aggressive or whether practicing oncologists are too conservative in their use of chemotherapy.

Adult↗

PubMed2003

Effects of misattribution in assigning cause of death on prostate cancer mortality rates.

PURPOSE: Estimate the magnitude of misattribution in death certification and to determine whether misattribution could explain temporal trends in New Mexico prostate cancer mortality. METHODS: Investigators retrospectively reviewed medical records to classify cause of death for men with prostate cancer who died in New Mexico in either 1985 or 1995. The investigator-assigned cause of death, either prostate cancer or another cause, was compared with the New Mexico Bureau of Vital Statistics' (BVS) assignment. Net misattribution was the difference between BVS and investigators in the number of deaths attributed to prostate cancer relative to the number attributed by investigators. RESULTS: Concordance for death certification between BVS and investigators was higher in 1995 (95.8%) than 1985 (85.1%), p <0.01, but net misattribution was higher in 1995 (16.8% vs. 1.9%). During this time, the crude prostate cancer mortality rate in New Mexico increased 33.5%, from 18.5 to 24.7 per 100,000. However, after adjusting for misattribution, mortality increased only 15.9%, from 18.2 to 21.1 per 100,000. CONCLUSIONS: Net misattribution in death certification was higher in 1995 than 1985. The adjusted increase in crude mortality rates was substantially less than the observed increase, suggesting that misattribution explained about half of the observed increase.

Cause of Death↗

PubMed2003

Ethnic differences at risk for gestational trophoblastic disease in New Mexico: A 25-year population-based study.

OBJECTIVE: The purpose of this study was to compare gestational trophoblastic disease incidence rates with the use of population-based data. STUDY DESIGN: All incident cases between 1973 and 1997 and live birth, pregnancy, and women at risk were tabulated with the use of data that were derived from the New Mexico Tumor Registry and Vital Records and Health Statistics Annual Reports. Statistical methods included trends analyses, odds ratios, and Poisson regression. RESULTS: Of 939 total cases, 312 non-Hispanic white women, 399 Hispanic white women, 201 American Indian women, and 27 other women were affected. Age-adjusted incidence rates were significantly higher for American Indian women (11.16%) compared with non-Hispanic (3.57%) or Hispanic white women (5.32%); the probability value was <.001. When live birth (1:438 women) and pregnancy (1:486 women) denominators were considered, American Indian women alone were at increased risk, and the ratio increased by 56% over 25 years. American Indian women were also at increased risk for partial mole (relative risk, 4.03; 95% CI, 2.57-6.31), invasive mole (relative risk, 26.7; 95% CI, 7.81-93.14), and choriocarcinoma (relative risk, 6.29; 95% CI, 1.81-22.66) variants. CONCLUSION: American Indians are at increased risk relative to the other predominant ethnic groups in New Mexico. Age-adjusted standardization provided a reproducible measurement that may be applicable across other registries.

Adolescent↗

PubMed2002

Prostate-specific antigen testing accuracy in community practice.

BACKGROUND: Most data on prostate-specific antigen (PSA) testing come from urologic cohorts comprised of volunteers for screening programs. We evaluated the diagnostic accuracy of PSA testing for detecting prostate cancer in community practice. METHODS: PSA testing results were compared with a reference standard of prostate biopsy. Subjects were 2,620 men 40 years and older undergoing (PSA) testing and biopsy from 1/1/95 through 12/31/98 in the Albuquerque, New Mexico metropolitan area. Diagnostic measures included the area under the receiver-operating characteristic curve, sensitivity, specificity, and likelihood ratios. RESULTS: Cancer was detected in 930 subjects (35%). The area under the ROC curve was 0.67 and the PSA cutpoint of 4 ng/ml had a sensitivity of 86% and a specificity of 33%. The likelihood ratio for a positive test (LR+) was 1.28 and 0.42 for a negative test (LR-). PSA testing was most sensitive (90%) but least specific (27%) in older men. Age-specific reference ranges improved specificity in older men (49%) but decreased sensitivity (70%), with an LR+ of 1.38. Lowering the PSA cutpoint to 2 ng/ml resulted in a sensitivity of 95%, a specificity of 20%, and an LR+ of 1.19. CONCLUSIONS: PSA testing had fair discriminating power for detecting prostate cancer in community practice. The PSA cutpoint of 4 ng/ml was sensitive but relatively non-specific and associated likelihood ratios only moderately revised probabilities for cancer. Using age-specific reference ranges and a PSA cutpoint below 4 ng/ml improved test specificity and sensitivity, respectively, but did not improve the overall accuracy of PSA testing.

Adult↗

PubMed2002

Is there a difference in survival for IA1 and IA2 adenocarcinoma of the uterine cervix?

OBJECTIVE: The goal of this study was to determine if International Federation of Obstetrics and Gynecology (FIGO) subdivision into IA1 versus IA2 is predictive of survival differences for early invasive adenocarcinoma. METHODS: The Surveillance, Epidemiology, and End-Results (SEER) Public-Use Database was used to identify all cases of IA1 and IA2 adenocarcinoma diagnosed between 1983 and 1997. A systematic literature search (MEDLINE 1966-2000) was used to identify all previously published cases. Stage, depth of invasion, node status, therapy, and survival were analyzed using Fisher's exact and log-rank tests. RESULTS: In SEER, 560 cases were identified: 200 IA1, 286 IA2, and 74 localized. Simple hysterectomy was performed in 272 (48.6%) and radical hysterectomy in 210 (37.5%). Positive lymph nodes were found in 3 of 197 (1.5%) who underwent lymphadenectomy, 2 of whom died. The censored survival by stage (mean follow-up 51.6 months) was not significantly different (P = 0.77) for IA1 versus IA2 (98.5% vs 98.6%). Combining these data with all other published series of early cervical adenocarcinoma, 1170 cases were identified, including 585 IA1, 358 IA2, and 227 "others," with less defined early disease. Of 531 (45.4%) who underwent lymphadenectomy, 15 (1.28%) had one or more positive nodes; of these, 11 (73.3%) recurred or died. For IA1 versus IA2 disease, there were no significant differences in the frequency of positive lymph nodes, recurrence, or death. However, "others," those with less well-defined lesions, or larger than IA2, were at increased risk. CONCLUSION: Early invasive adenocarcinoma (IA1 and IA2) has an excellent prognosis and conservative surgery may be appropriate. Since current FIGO staging definitions do not distinguish high- from low-risk disease, individualization of therapy based on pathology review, risk assessment, and patient preference is recommended.

Adenocarcinoma↗