Promoting informed decisions about cancer screening in communities and healthcare systems

Individuals are increasingly involved in decisions about their health care. Shared decision making (SDM), an intervention in the clinical setting in which patients and providers collaborate in decision making, is an important approach for informing patients and involving them in their health care. However, SDM cannot bear the entire burden for informing and involving individuals. Population-oriented interventions to promote informed decision making (IDM) should also be explored. This review provides a conceptual background for population-oriented interventions to promote informed decisions (IDM interventions), followed by a systematic review of studies of IDM interventions to promote cancer screening. This review specifically asked whether IDM interventions (1) promote understanding of cancer screening, (2) facilitate participation in decision making about cancer screening at a level that is comfortable for individuals; or (3) encourage individuals to make cancer-screening decisions that are consistent with their preferences and values.Fifteen intervention arms met the intervention definition. They used small media, counseling, small-group education, provider-oriented strategies, or combinations of these to promote IDM. The interventions were generally consistent in improving individuals' knowledge about the disease, accuracy of risk perceptions, or knowledge and beliefs about the pros and cons of screening and treatment options. However, few studies evaluated whether these interventions resulted in individuals participating in decision making at a desirable level, or whether they led to decisions that were consistent with individuals' values and preferences. More research is needed on how best to promote and facilitate individuals' participation in health care. Work is especially needed on how to facilitate participation at a level desired by individuals, how to promote decisions by patients that are consistent with their preferences and values, how to perform effective and cost-effective IDM interventions for healthcare systems and providers and in community settings (outside of clinical settings), and how to implement these interventions in diverse populations (such as populations that are older, nonwhite, or disadvantaged). Finally, work is needed on the presence and magnitude of barriers to and harms of IDM interventions and how they might be avoided.

Comparison of screening mammography in the United States and the United kingdom

CONTEXT

Screening mammography differs between the United States and the United Kingdom; a direct comparison may suggest methods to improve the practice.

OBJECTIVE

To compare screening mammography performance between the United States and the United Kingdom among similar-aged women.

DESIGN, SETTING, AND PARTICIPANTS

Women aged 50 years or older were identified who underwent 5.5 million mammograms from January 1, 1996, to December 31, 1999, within 3 large-scale mammography registries or screening programs: the Breast Cancer Surveillance Consortium (BCSC, n = 978 591) and National Breast and Cervical Cancer Early Detection Program (NBCCEDP, n = 613 388) in the United States; and the National Health Service Breast Screening Program (NHSBSP, n = 3.94 million) in the United Kingdom. A total of 27 612 women were diagnosed with breast cancer (invasive or ductal carcinoma in situ) within 12 months of screening among the 3 groups.

MAIN OUTCOME MEASURES

Recall rates (recommendation for further evaluation including diagnostic imaging, ultrasound, clinical examination, or biopsy) and cancer detection rates were calculated for first and subsequent mammograms, and within 5-year age groups.

RESULTS

Recall rates were approximately twice as high in the United States than in the United Kingdom for all age groups; however, cancer rates were similar. Among women aged 50 to 54 years who underwent a first screening mammogram, 14.4% in the BCSC and 12.5% in the NBCCEDP were recalled for further evaluation vs only 7.6% in the NHSBSP. Cancer detection rates per 1000 mammogram screens were 5.8, 5.9, and 6.3, in the BCSC, NBCCEDP, and NHSBSP, respectively. Recall rates were lower for subsequent examinations in all 3 settings but remained twice as high in the United States. A similar percentage of women underwent biopsy in each setting, but rates of percutaneous biopsy were lower and open surgical biopsy higher in the United States. Open surgical biopsies not resulting in a diagnosis of cancer (negative biopsies) were twice as high in the United States than in the United Kingdom. Based on a 10-year period of screening 1000 women aged 50 to 59 years, 477, 433, and 175 women in the BCSC, NBCCEDP, and NHSBSP, respectively, would be recalled; and for women aged 60 to 69 years, 396, 334, and 133 women, respectively. The estimated cancer detection rates per 1000 women aged 50 to 59 years were 24.5, 23.8, and 19.4, respectively, and for women aged 60 to 69 years, 31.5, 26.6, and 27.9, respectively.

CONCLUSIONS

Recall and negative open surgical biopsy rates are twice as high in US settings than in the United Kingdom but cancer detection rates are similar. Efforts to improve US mammographic screening should target lowering the recall rate without reducing the cancer detection rate.

Risk of cervical cancer associated with extending the interval between cervical-cancer screenings

BACKGROUND

Although contemporary guidelines suggest that the intervals between Papanicolaou tests can be extended to three years among low-risk women with previous negative tests, the excess risk of cervical cancer associated with less frequent than annual screening is uncertain.

METHODS

We determined the prevalence of biopsy-proven cervical neoplasia among 938,576 women younger than 65 years of age, stratified according to the number of previous consecutive negative Papanicolaou tests. Using a Markov model that estimates the rate at which dysplasia will progress to cancer, we estimated the risk of cancer within three years after one or more negative Papanicolaou tests, as well as the number of additional Papanicolaou tests and colposcopic examinations that would be required to avert one case of cancer given a particular interval between screenings.

RESULTS

Among 31,728 women 30 to 64 years of age who had had three or more consecutive negative tests, the prevalence of biopsy-proven cervical intraepithelial neoplasia of grade 2 was 0.028 percent and the prevalence of grade 3 neoplasia was 0.019 percent; none of the women had invasive cervical cancer. According to our model, the estimated risk of cancer with annual Papanicolaou tests for three years was 2 in 100,000 among women 30 to 44 years of age, 1 in 100,000 among women 45 to 59 years of age, and 1 in 100,000 among women 60 to 64 years of age; these risks would be 5 in 100,000, 2 in 100,000, and 1 in 100,000, respectively, if screening were performed once three years after the last negative test. To avert one additional case of cancer by screening 100,000 women annually for three years rather than once three years after the last negative test, an average of 69,665 additional Papanicolaou tests and 3861 colposcopic examinations would be needed in women 30 to 44 years of age and an average of 209,324 additional Papanicolaou tests and 11,502 colposcopic examinations in women 45 to 59 years of age.

CONCLUSIONS

As compared with annual screening for three years, screening performed once three years after the last negative test in women 30 to 64 years of age who have had three or more consecutive negative Papanicolaou tests is associated with an average excess risk of cervical cancer of approximately 3 in 100,000.

Validation of self-reported screening mammography histories among women with and without breast cancer

As part of a case-control study of the efficacy of screening mammography, the authors validated the mammography histories of 2,495 women aged 40-64 years with incident breast cancer diagnosed in 1994-1998 and a 25% random sample of 615 controls never diagnosed with breast cancer, all reporting a mammogram in the past 5 years. Subjects from five metropolitan areas of the United States were cross-classified by facility records ("gold standard") and self-report according to history of a recent screening mammogram (within 1 year or within 2 years). Sensitivity and specificity of self-reported screening at 1 year were 0.93 and 0.82, respectively, for cases and 0.92 and 0.80 for controls. At 2 years, sensitivity and specificity were 0.97 and 0.78 for both cases and controls. Confidence intervals for the differences in sensitivity and specificity were narrow and included zero. Scant evidence was found of telescoping (recollection of events as more recent than actual). Findings suggest that, in an interview-based case-control study of the efficacy of screening mammography, 1) estimated true prevalences of recent screening mammography adjusted for sensitivity and specificity will be slightly lower than self-reported prevalences, and 2) differential misclassification of exposure status is slight. Therefore, odds ratios will likely be biased toward the null, underestimating screening efficacy.

Risk factors for failure to detect a cancer during clinical breast examinations (United States)

BACKGROUND

Although clinical breast examinations (CBEs) provide important opportunities to detect breast cancer, little is known about factors that affect cancer detection during CBEs performed in community settings. To evaluate several potential factors, we analyzed data from 1,056,153 cancer screening records reported to the National Breast and Cervical Cancer Early Detection Program (NBCCEDP).

METHODS

Using case-series methods, we compared 2159 cancers missed during CBEs with 3161 cancers detected during CBEs. Cancers missed during CBE were found by mammography and confirmed by biopsy or fine needle aspiration.

RESULTS

After controling for cancer stage, tumor size, and breast symptoms at time of CBE, we found that patient age and CBE history were significantly associated with the likelihood of cancer detection. Compared to women 50-59, women 40-49 were more likely to have their cancer detected during CBE (odds ratio (OR) = 1.84, 95% confidence interval (95% CI) 1.47-2.29), while women 70 and older were less likely to have it detected (OR = 0.74, 95% CI: 0.55-1.00). Among women receiving their first NBCCEDP-funded CBE, 67.5% had their cancer detected by CBE. Among women receiving their second or third CBE, the values were 59.3 and 48.8%, respectively. In an adjusted logistic model, a significant inverse relationship was observed between number of prior CBEs and percent of cancers detected in the index CBE (OR = 0.79, 95% CI: 0.72-0.88).

CONCLUSIONS

Among women diagnosed with breast cancer, older women and those who have had multiple CBEs were more likely to have their cancer missed during CBE.

Progress in cancer screening practices in the United States: results from the 2000 National Health Interview Survey

BACKGROUND

Understanding differences in cancer screening among population groups in 2000 and successes or failures in reducing disparities over time among groups is important for planning a public health strategy to reduce or eliminate health disparities, a major goal of Healthy People 2010 national cancer screening objectives. In 2000, the new cancer control module added to the National Health Interview Survey (NHIS) collected more detailed information on cancer screening compared with previous surveys.

METHODS

Data from the 2000 NHIS and earlier surveys were analyzed to discern patterns and trends in cancer screening practices, including Pap tests, mammography, prostate specific antigen (PSA) screening, and colorectal screening. The data are reported for population subgroups that were defined by a number of demographic and socioeconomic characteristics.

RESULTS

Women who were least likely to have had a mammogram within the last 2 years were those with no usual source of health care (61%), women with no health insurance (67%), and women who immigrated to the United States within the last 10 years (61%). Results for Pap tests within the last 3 years were similar. Among both men and women, those least likely to have had a fecal occult blood test or endoscopy within the recommended screening interval had no usual source of care (14% for men and 18% for women), no health insurance (20% for men and 18% for women), or were recent immigrants (20% for men and 18% for women). An analysis of changes in test use since the 1987 survey indicates that the disparities are widening among groups with no usual source of care.

CONCLUSIONS

No striking improvements have been observed for the groups with greatest need. Although screening use for most groups has increased since 1987, major disparities remain. Some groups, notably individuals with no usual source of care and the uninsured are falling further behind; and, according to the 2000 data, recent immigrants also experience a significant gap in screening utilization. More attention is needed to overcome screening barriers for these groups if the population benefits of cancer screening are to be achieved.

Building the infrastructure for nationwide cancer surveillance and control--a comparison between the National Program of Cancer Registries (NPCR) and the Surveillance, Epidemiology, and End Results (SEER) Program (United States)

OBJECTIVE

In preparation for jointly publishing official government cancer statistics, the Centers for Disease Control and Prevention (CDC) and the National Cancer Institute (NCI) compared incidence rates from NCI's Surveillance Epidemiology and End Results (SEER) Program and CDC's National Program of Cancer Registries (NPCR).

METHODS

Data for 1999 covering 78% of the US population were obtained from SEER and selected NPCR registries that met high quality data criteria. Incidence rates (per 100,000 population) were age-adjusted to the 2000 US standard population, and 95% gamma confidence intervals were estimated.

RESULTS

NPCR rates for all sites combined were higher than SEER rates (males: NPCR 553.6, SEER 538.7; females: NPCR 420.8, SEER 412.5), but rates for specific cancer sites varied by registry program. Rates for colon cancer (males: NPCR 47.0, SEER 42.7; females: NPCR 36.5, SEER 33.8) and tobacco-related cancers were higher in NPCR than SEER. In contrast, NPCR rates were lower than SEER rates for cancers of the female breast (NPCR 134.0, SEER 135.9), prostate (NPCR 162.0, SEER 170.2), and melanoma as well as for cancers more common among Asians and Pacific Islanders (e.g., stomach cancer).

CONCLUSIONS

Rate differences may arise from population differences in socio-demographic characteristics, screening use, health behaviors, exposure to cancer causing agents or registry operations factors.

Reducing disparities in breast cancer survival: a Columbia University and Avon Breast Cancer Research and Care Network Symposium

On November 8th, 2001, faculty from Universities, government and non-profit community organizations met to determine how, separately and together, they could address disparities in survival of women with breast cancer in the diverse patient populations served by their institutions. Studies and initiatives directed at increasing access had to date met modest success. The day was divided into three sections, defining the issues, model programs, government initiatives and finally potential collaborations. By publishing these proceedings, interested readers will be aware of the ongoing programs and studies and can contact the investigators for more information. The Avon Foundation funded this symposium to bring together interested investigators to share programmatic experiences, data and innovative approaches to the problem.

Application of population screening principles to genetic screening for adult-onset conditions

Recent advances in molecular genetics have highlighted the potential use of genetic testing to screen for adult-onset chronic diseases. Several issues must be addressed, however, before such tests can be recommended for population-based prevention programs. These issues include the adequacy of the scientific evidence, the balance of risks and benefits, the need for counseling and informed consent, and the costs and resources required. Ongoing assessment of the screening program and quality assurance of laboratory testing are also needed. This paper considers the application of general principles for mass screening to genetic testing for susceptibility to adult-onset chronic diseases. Evaluation of proposals for genetic screening in context of these principles reveals that needed evidence is often absent, particularly with respect to the predictive value of tests, efficacy of interventions, and social consequences of testing. The principles of population screening are developed into a framework for public health policy on genetic screening that has three stages: assessment of the screening test and interventions for those who test positive, including assessment of risks and costs, policy development, and program evaluation. Essential elements are identified, including evaluation of evidence and processes for consensus development and program evaluation. The proposed framework for public health policymaking outlined in this commentary, when combined with future efforts that involve an authoritative consensus process, may be useful for the evaluation and planning of genetic screening programs aimed at reducing morbidity and mortality from adult-onset chronic diseases.

Pre-existing tumor-sensitized T cells are essential for eradication of established tumors by IL-12 and cyclophosphamide plus IL-12

The antitumor immune response activated by IL-12, especially by a combination of cyclophosphamide and IL-12 (Cy+IL-12), is clinically significant in certain experimental tumor models, in that a number of well-established (10-20 mm in diameter) s.c. tumors are completely eradicated. Furthermore, Cy+IL-12 treatment is also able to eradicate well-established grossly detectable experimental lung metastases and advanced ascites tumors. Despite the dramatic antitumor effects seen in some tumor models, Cy+IL-12 fails to induce regression of other established tumors. Characterization of tumor immunogenicity shows that all tumors responding to IL-12 and Cy+IL-12 treatments are immunogenic tumors, in that an antitumor immune response is detectable in tumor-bearing hosts upon tumor establishment. In contrast, none of the nonimmunogenic tumor responds to IL-12 and Cy+IL-12 treatments. Analysis of cellular requirements for successful tumor rejection through an adoptive cell transfer approach reveals that the presence of tumor-sensitized, but not naive, T cells is essential for tumor rejection by IL-12 and Cy+IL-12. Transfer of these tumor-sensitized T cells must be conducted before, but not after, IL-12 treatment in order for tumor rejection to occur. The requirement of sensitized T cells is also tumor specific. In mice bearing immunogenic tumors, the presence of pre-existing tumor-sensitized T cells is demonstrated by adoptive cell transfer experiments using purified spleen T cells from these mice. Results from our study show that Cy+IL-12-based immunotherapy of cancer may be highly effective and that pre-existing tumor-sensitized T cells are essential for the success of the therapy.

Factors associated with continued participation in mammography screening

BACKGROUND

Relatively little is known about factors that predict ongoing participation in mammography screening at regular intervals. Members of managed care plans have access to this preventive service; yet, many still do not receive it routinely.

METHODS

Using administrative data from HIP Health Plan of New York, a group model HMO, 24,215 women ages 50-80 years identified as having a screening mammogram during the baseline period were followed for 2 years to determine demographic and utilization factors that might be related to having a subsequent mammogram within the recommended time interval.

RESULTS

Of the 24,215 women with an index mammogram, 71.8;pc had a subsequent screening mammogram within 2 years. Women ages 65-74 years and those with Medicare coverage had the highest mammogram rates among the age and coverage categories. Number of primary care and gynecology physician visits was strongly related to having a subsequent mammogram. The average (mean) time between index and subsequent mammogram was 14.4 months.

CONCLUSION

The significance of health plan visits in subsequent mammography underscores the importance of physician-patient communication in a managed care plan and the integration of health plan members into the HMO delivery system. Even in this environment with equal access for all types of coverage, Medicaid members were less likely to receive this preventive service.

A randomized intervention to improve ongoing participation in mammography

OBJECTIVE

To test the effectiveness of interventions intended to increase rates of regular breast cancer screening, according to recommended guidelines.

STUDY DESIGN

A randomized controlled trial of 2 outreach interventions (a mail reminder and a telephone reminder plus appointment scheduling) compared with a routine publicity campaign to encourage continued participation in mammography screening.

PARTICIPANTS AND METHODS

Participants were 1908 women aged 50 to 75 years continuously enrolled in a large group-model HMO during the study who underwent a bilateral mammogram during the first quarter of 1994 and no subsequent mammogram during the next 18 to 21 months. Data were obtained from health plan administrative data files supplemented by medical chart review. Women were randomly assigned to receive (1) a mail reminder, (2) a telephone reminder, or (3) routine publicity on mammography for all women. The outcome measure was a mammogram received after the intervention period and within 2 years of the initial mammogram date.

RESULTS

Bivariate and multivariate statistical analyses showed that participation was significantly higher for women contacted by telephone than through routine publicity. Mail reminders were no more effective than a routine publicity campaign. Primary care physician and gynecologist visits increased the likelihood of a subsequent mammogram for women in all intervention groups.

CONCLUSIONS

Telephone contact by regular health plan staff was more successful than publicity in encouraging continued participation in mammography screening in women enrolled in a group-model managed health care plan. Because mailings did not influence participation in mammography screening, health plans should be cautious about investing in member mailings without first evaluating their effectiveness in the context of existing outreach efforts.

Early-stage breast cancer treatment among medically underserved women diagnosed in a national screening program, 1992-1995

BACKGROUND

Little research has been conducted on the breast cancer treatment of low income, underserved women. This study was designed to describe initial treatment of breast cancer among low-income women diagnosed through federally funded screening programs in Detroit, Michigan, and the states of New Mexico and California; and to compare the treatment received by program women with early-stage breast cancer with that of all women diagnosed in those regions.

METHODS

Data from the three screening programs were linked with cancer registry data from the corresponding geographic areas. All women diagnosed between 1992 and 1995 through the state-based screening programs and all women contemporaneously diagnosed with breast cancer in the three regions were studied. Descriptive analyses were done of the proportion of women with breast cancer receiving treatment; the proportion of early-stage breast cancer (stage I or II) cases treated with breast-conserving surgery, and the proportion treated with mastectomy; and among women with breast-conserving surgery, the proportion receiving radiation therapy. Logistic regression models controlled for age and stage at diagnosis, race or ethnicity and geographic region.

RESULTS

Less than 2% of program women diagnosed with breast cancer received no treatment. More than two of five women with early-stage breast cancer underwent breast-conserving surgery, with 72% of these women receiving radiation therapy. Multivariate regression analysis revealed that women with stage IIA or IIB breast cancer had lower odds of undergoing breast-conserving surgery than women with stage I (0.51 [95% CI = 0.30-0.87] and 0.36 [95% CI = 0.19-0.70], respectively). Women over age 65 and those with incompletely staged cancer had the lowest odds for receiving radiation therapy after breast-conserving surgery (0.29 [95% CI = 0.09-0.99] and 0.14 [95% CI = 0.03-0.72], respectively). Women diagnosed through the screening programs had odds of undergoing breast-conserving surgery similar to those of all women in the regions (1.11 [95% CI= 0.89-1.39]).

CONCLUSIONS

Treatment patterns for women diagnosed with early-stage breast cancer through three state-based screening programs appear to have been similar to those reported in the literature. In addition, their treatment appears to have been similar to that of other women during the same time period.

Antimetastatic efficacy of adjuvant gemcitabine in a pancreatic cancer orthotopic model

Gemcitabine is a promising new agent that has been recently studied for palliation of advanced (stage IV) unresectable pancreatic cancer. We hypothesized that adjuvant gemcitabine would reduce recurrence and metastases following surgical resection of pancreatic cancer. To test this hypothesis, we evaluated gemcitabine on a green fluorescent protein (GFP) transductant of the human pancreatic cancer cell line BxPC-3 (BxPC-3-GFP) using surgical orthotopic implantation (SOI) in nude mice. GFP enabled high resolution fluorescent visualization of primary and metastatic growth. Five weeks after SOI, the mice were randomized into three groups: Group I received exploratory laparotomy only. Group II underwent surgical resection of the pancreatic tumor without further treatment. Group III underwent tumor resection followed by adjuvant treatment with gemcitabine, 100 mg/kg every three days for a total of four doses, starting two days after resection. The mice were sacrificed at thirteen weeks following implantation and the presence and location of recurrent tumor was recorded. Gemcitabine reduced the recurrence rate to 28.6% compared to 70.6% with resection only (P = 0.02) and reduced metastatic events 58% in the adjuvant group compared to resection only. This study, demonstrating that gemcitabine is effective as adjuvant chemotherapy post-pancreatectomy, suggests this new indication of the drug clinically.

Self-reported Papanicolaou smears and hysterectomies among women in the United States

OBJECTIVE

To evaluate the potential overuse of Papanicolaou smears among women who have had a hysterectomy.

METHODS

We analyzed two surveys of US women aged 18 years or older, the Behavioral Risk Factor Surveillance System (1992-1997) and the National Health Interview Survey (1993-1994), and one survey of US hospitals (National Hospital Discharge Survey, 1980-1997). We examined the number of women who have had a hysterectomy who had a recent (within 3 years) Papanicolaou smear. We also examined trends in the proportions and rates of hysterectomies by diagnoses and type of procedure that potentially could require a Papanicolaou smear.

RESULTS

From the Behavioral Risk Factor Surveillance System, an estimated 21.2% of US women have had a hysterectomy. Among women who have had a hysterectomy, 78.3% had a recent Papanicolaou smear. Among those reporting no hysterectomy, 82.1% had a recent Papanicolaou smear. Estimates from the National Health Interview Survey were similar. From the National Hospital Discharge Survey, an estimated 6.7% to 15.4% of women with a history of hysterectomy would require a subsequent Papanicolaou smear because they had a diagnosis related to cervical neoplasia or because they had undergone a supracervical hysterectomy. For an estimated 10.6-11.6 million of the 12.5 million women who had a hysterectomy and a recent Papanicolaou smear, that test could be considered unnecessary.

CONCLUSION

Continued Papanicolaou screening of women without an intact uteri may result in excessive use of resources in time and money with minimal impact on decreasing cervical cancer.

Race-specific results of Papanicolaou testing and the rate of cervical neoplasia in the National Breast and Cervical Cancer Early Detection Program, 1991-1998 (United States)

OBJECTIVE

To describe differences in cervical screening and biopsy results by race or ethnicity from women in the National Breast and Cervical Cancer Early Detection Program (NBCCEDP).

METHODS

We examined the percentage of abnormalities detected by Papanicolaou (Pap) tests and the rate of biopsy-diagnosed high-grade precancerous or cancerous lesions by racial or ethnic group.

RESULTS

Almost half the 628,085 women screened were members of racial or ethnic minority groups. American Indian or Alaska Native women were more likely than others to report never having had a prior Pap test. American Indian or Alaska Native women had the highest proportion of abnormal Pap tests for first program screens (4.4%), followed by blacks (3.2%), whites (3.0%), Hispanics (2.7%), and Asians or Pacific Islanders (1.9%). Whites had the highest biopsy detection rate of high-grade lesions for first program screens (9.9 per 1000 Pap tests), followed by Hispanics (7.6), blacks (7.1), American Indians or Alaska Natives (6.7), and Asians or Pacific Islanders (5.4).

CONCLUSIONS

This program provides important data on the prevalence of cervical neoplasia among diverse populations. Our findings that black women with a high-grade Pap test were less likely to get a work-up are disconcerting and merit further study and ultimate correction.

Multiple endocrine neoplasia type 2B — genetic basis and clinical expression

Multiple endocrine neoplasia (MEN) type 2B is a heritable endocrine disorder characterized by medullary thyroid carcinoma (MTC), pheochromocytoma, multiple mucosal neuromas, and a marfanoid habitus. Intestinal ganglioneuromatosis, corneal nerve thickening and skeletal abnormalities are also often present. The disease is inherited in an autosomal dominant fashion and is caused by a single mutation in the RET proto-oncogene, with a methionine to threonine substitution at codon 918. The MTC in MEN 2B presents at an earlier age and tends to be more aggressive than the MTC in MEN 2A. It is multicentric and bilateral and occurs as young as age 3, with early lymph node metastases. Pheochromocytoma is also often bilateral but is rarely malignant. If pheochromocytoma is detected, adrenalectomy should precede thyroidectomy to avoid intraoperative catecholamine crisis. Patients at risk for MEN 2B should undergo genetic screening in infancy. Total thyroidectomy should be performed on all patients positive for RET mutations even prior to the onset of clinical symptoms.

Colorectal cancer screening participation by older women

OBJECTIVE

Although recent screening guidelines recommend annual fecal occult blood testing (FOBT) for adults aged > or = 50, a number of studies report that these tests are underused. Systematic efforts to increase awareness of colorectal cancer (CRC) and to promote screening participation are needed to meet national objectives for CRC control.

METHODS

This study examined CRC-screening practices and evaluated factors related to recent participation in screening by FOBT in a sample of women aged 50 to 80 who were surveyed about their use of clinical preventive services at Group Health Cooperative, a managed care organization in western Washington State.

RESULTS

Of the 931 women eligible for analysis, 75% reported ever having been screened by FOBT and 48% reported having been screened within 2 years before the survey. Participation in screening did not vary by demographic characteristics or by perceived or actual risk of CRC. Women with a positive attitudes toward CRC screening had sevenfold greater odds of recent screening by FOBT (odds ratio=7.1; 95% confidence interval, 4.4 to 11.6). Only 58% of study women reported that their physicians encouraged CRC screening, but this factor was strongly related to participation (odds ratio=12.7; 95% confidence interval, 6.6 to 24.4).

CONCLUSIONS

We identified several areas in which understanding of CRC risk may be low. As a whole, these findings suggest that effective strategies to control CRC may include efforts to improve knowledge of risk and prevention, but must also appeal directly to primary care physicians to identify and address their barriers to screening recommendations.

Mammography and breast cancer detection by race and Hispanic ethnicity: results from a national program (United States)

OBJECTIVE

Some of the racial and ethnic variation in breast cancer incidence rates may reflect differential use of mammography. We report breast cancer rates using mammography and diagnostic data from five race/ethnicity groups.

METHODS

Mammography data were analyzed for 573,751 women who received breast cancer screening between July 1991 and March 1998 from the National Breast and Cervical Cancer Early Detection Program (NBCCEDP). Abnormal mammography rates, breast cancer detection rates, and cancer stage distribution data are presented by race/ethnicity and screening round (first or subsequent).

RESULTS

For the first screening round, percentages of abnormal mammographies ranged from 7.3% among black women to 9.3% among Asian/Pacific Islander women. Cancer detection rates ranged from 4.9 cancers per 1000 mammograms for Hispanic and American Indian/Alaska Native (AI/AN) women to 7.7 per 1000 for white women. Subsequent round rates were lower but varied similarly. AI/AN women had the highest percentage (68%) of first-round cancers detected in the early stage (range for the other groups: 52-63%).

CONCLUSIONS

Breast cancer detection rates for racial and ethnic groups in this program varied less than published population-based incidence rates. Differential use of mammography among these groups may account for some of the variation reported for breast cancer incidence.

Frequency of cervical smear abnormalities within 3 years of normal cytology

OBJECTIVE

To compare cervical screening outcomes associated with age and three screening intervals, 1, 2, and 3 years.

METHODS

We did a prospective cohort study comprising 128,805 women at community-based clinics throughout the United States who were screened for cervical cancer within 3 years of normal smears through the National Breast and Cervical Cancer Early Detection Program. We determined the incidence of cytologic abnormalities defined as atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (SIL), high-grade SIL, and suggestive of squamous cell cancer.

RESULTS

Over the 3 years after normal smear results, the incidence of new smears interpreted as high-grade SIL or suggestive of squamous cell cancer (high-grade SIL or worse) was 66 of 10,000 for women under 30 years old, 22 of 10, 000 for those 30-49 years, 15 of 10,000 for those 50-64 years, and 10 of 10,000 for those over 65 years. Age-adjusted incidence rates of high-grade SIL or worse were similar for women screened at 9-12 months (25 of 10,000), 13-24 months (29 of 10,000), and 25-36 months (33 of 10,000) after normal smears (P =.46). Age-adjusted incidence rates of ASCUS, the most common cytologic abnormality, did not change (P =.36). Incidence of smears interpreted as low-grade SIL increased as time from the normal smear increased (P =.01).

CONCLUSIONS

Within 3 years after normal cytology results, cervical smears interpreted as high-grade SIL or worse are uncommon, and the incidence rate is unrelated to the time since last normal smear. Optimal screening strategies for women with recent normal cytology results should be based on comprehensive modeling studies that incorporate the true risks and benefits of repetitive screening.

Findings from 752,081 clinical breast examinations reported to a national screening program from 1995 through 1998

BACKGROUND AND METHODS

Mammography programs have received extensive study, but little is known about the outcome of clinical breast examinations (CBEs) performed in community settings. Consequently, we analyzed data from the National Breast and Cervical Cancer Early Detection Program on CBEs provided to low-income women from 1995 through 1998 and determined the percentage of CBEs considered to be abnormal, suspicious for cancer; the rates of cancer detection; and the sensitivity, specificity, and positive predictive value of CBEs.

RESULTS

We analyzed data from 752081 CBEs and found that 6.9% of all CBEs were coded abnormal, suspicious for cancer, and that 5.0 cancers were detected per 1000 examinations (95% confidence interval [CI] = 4.9-5.2). The values observed for sensitivity (58.8%) and specificity (93.4%) were comparable to those reported for the CBE component of clinical trials. The observed positive predictive value was 4.3%. About 74% of all records also reported mammography results. The cancer-detection rate among records reporting an abnormal CBE and normal mammography was 7.4 cancers per 1000 records (95% CI = 6. 3-8.4). When the CBE was normal but the mammography was abnormal, the rate was 42.0 cancers per 1000 records (95% CI = 39.9-44.1). When both CBE and mammography results were abnormal, the rate was 170.3 cancers per 1000 records (95% CI = 162.7-177.9). Cancer detection could not be attributed entirely to CBE or mammography on 38% of the records in the latter subset because the tests were performed on the same day.

CONCLUSION

CBEs performed in community-based screening programs can detect breast cancers as effectively as CBEs performed in clinical trials and may modestly improve early-detection campaigns.

A meta-analysis of estrogen replacement therapy and risk of epithelial ovarian cancer

Estrogen replacement therapy (ERT) has not been associated with epithelial ovarian cancer in most reported epidemiologic studies that have looked for an association. Some studies may have found weak statistically nonsignificant associations because the number of cases or number of women who reported estrogen use was small. We performed a meta-analysis of data from 15 case-control studies that provided data on ERT and risk of epithelial ovarian cancer. The 15 combined studies were statistically heterogeneous (chi(2) (14) = 26. 3, P < 0.05) in terms of the effect they found. When we combined these studies using a random effects model, we did not find a significant association of ERT with ovarian cancer (odds ratio = 1.1, 95% confidence interval = 0.9-1.3). There was no clear evidence of a dose-response relation with increasing duration of estrogen use in a subset of five studies that reported estrogen use by duration (overall slope = 0.0012, 95% confidence interval = -0.0055 to 0. 0080). The influences of statistical outliers, study design (hospital or clinic controls vs. community controls), and location (U.S. and Canada vs. Europe and Australia) were examined. The odds ratio was 1.3 (95% confidence interval = 1.0-1.6) in the relatively homogeneous subset of four U.S. case-control studies with community controls, but we cannot rule out the possibility of uncontrolled confounding. The odds ratios for estrogen use for other subgroups defined by geographic location and type of control group were not significantly different from one.