Colorado Central Cancer Registry Research Articles

Building Data Infrastructure for Disease-Focused Health Economics Research.

Data infrastructure for cancer research is centered on registries that are often augmented with payer or hospital discharge databases, but these linkages are limited. A recent alternative in some states is to augment registry data with All-Payer Claims Databases (APCDs). These linkages capture patient-centered economic outcomes, including those driven by insurance and influence health equity, and can serve as a prototype for health economics research. To describe and assess the utility of a linkage between the Colorado APCD and Colorado Central Cancer Registry (CCCR) data for 2012-2017. This cohort study of 91,883 insured patients evaluated the Colorado APCD-CCCR linkage on its suitability to assess demographics, area-level data, insurance, and out-of-pocket expenses 3 and 6 months after cancer diagnosis. The linkage had high validity, with over 90% of patients in the CCCR linked to the APCD, but gaps in APCD health plans limited available claims at diagnosis. We highlight the advantages of the CCCR-APCD, such as granular race and ethnicity classification, area-level data, the ability to capture supplemental plans, medical and pharmacy out-of-pocket expenses, and transitions in insurance plans. Linked data between registries and APCDs can be a cornerstone of a robust data infrastructure and spur innovations in health economics research on cost, quality, and outcomes. A larger infrastructure could comprise a network of state APCDs that maintain linkages for research and surveillance.

Treatment Disparities in Radiation and Hormone Therapy Among Women Covered by Medicaid vs Private Insurance in Cancer Registry and Claims Data

Prior research has reported undertreatment among patients with cancer who are insured by Medicaid, but this finding may be due, in part, to incomplete data in cancer registries. To compare disparities in radiation and hormone therapy between women with breast cancer covered by Medicaid and those with private insurance using the Colorado Central Cancer Registry (CCCR) and CCCR data supplemented with All Payer Claims Data (APCD). This observational cohort study included women aged 21 to 63 years who received breast cancer surgery. We linked the CCCR and Colorado APCD to identify Medicaid and privately insured women who were newly diagnosed with invasive, nonmetastatic breast cancer between January 1, 2012, and December 31, 2017. In the radiation treatment analysis, we narrowed the sample to women who received breast-conserving surgery (Medicaid, n = 1408; private, n = 1984) and in the hormone therapy analysis, we selected women who were hormone-receptor positive (Medicaid, n = 1156; private, n = 1667). We used logistic regression to estimate the likelihood of treatment within 12 months to assess whether the results varied between data sources. There were 3392 and 2823 participants in the radiation and hormone therapy cohorts, respectively. The mean (SD) age was 51.71 (8.30) years in the radiation therapy cohort, and 52.00 (8.16) years in the hormone therapy cohort. Among the participants, there were 140 (4%) and 105 (4%) who were Black non-Hispanic, 499 (15%) and 406 (14%) who were Hispanic, 2602 (77%) and 2190 (78%) were White, and 151 (4%) and 122 (4%) were other/unknown in the radiation and hormone therapy cohorts, respectively. A higher percentage of women were aged 50 years or younger in the Medicaid samples (40% vs 34% in the privately insured sample) and identified as non-Hispanic Black (about 7%) or Hispanic (approximately 24%). Treatment was underreported in both sources, but to a lesser extent in the APCD (2.5% and 2.0% for Medicaid and private insurance, respectively) compared with CCCR (19.5% and 13.3% for Medicaid and private insurance, respectively). Using CCCR data, Women with Medicaid insurance were 4 (95% CI, -8 to -1; P = .02) and 10 (95% CI, -14 to -6; P < .001) percentage points less likely to have a record of radiation and hormone therapy compared with privately insured women, respectively. Using combined CCCR and APCD, no statistically significant disparity was observed in radiation or hormone therapy between Medicaid-insured and privately insured women. Among women with breast cancer covered by Medicaid vs private insurance, cancer treatment disparities may be overestimated if based solely on cancer registry data.

Post-Acute Care Outcomes of Cancer Patients

Background: Post-acute care outcomes for patients with cancer <65 with multiple payers are largely unknown. Objective: Describe the population and outcomes of younger adults discharged to skilled nursing facility (SNF) and those discharged home or with home health care six months following hospitalization. Design: Descriptive cohort analysis. Setting/Subjects: Using a linkage between the Colorado All Payers Claims Database and the Colorado Central Cancer Registry, we studied patients <65 with stage III or IV advanced cancer between 2012 and 2017. Measurements: Receipt of cancer treatment, 30-day readmission, death, and hospice use. Groups of interest were compared by patient demographics and disease characteristics using chi-square tests. Logistic regression was used to describe unadjusted and adjusted outcome rates among discharge setting. Kaplan-Meier method was used to estimate survival by discharge destination. Results: Three percent of patients were discharged to SNF, 79.0% to home, and 18.0% to home health care. SNF discharges were less likely to receive cancer treatment. Among decedents, 39.0%, 51.0%, and 58.0% of SNF, home, and home health care discharges received hospice, respectively. Patients with Medicaid were more likely to be discharged to an SNF. Black/Hispanic patients were more likely to have Medicaid and received less radiation and hospice care, irrespective of discharge location. Those who were discharged to SNF were more likely to receive radiation compared to White patients. Conclusions: Younger patients with cancer discharged to SNF were unlikely to receive cancer treatment and hospice care before death. Racial disparities exist in cancer treatment receipt and hospice use warranting further investigation.

Pre-implementation evaluation for an HPV vaccine provider communication intervention among primary care clinics

ObjectivesInterventions to improve health care provider communication about HPV vaccination can increase vaccine acceptance. Our objectives were to (1) identify clinics in locations with high HPV-associated cancer and low HPV-vaccination rates that would potentially benefit from dissemination of a proposed HPV Provider Communication intervention and (2) use qualitative interviews and a dissemination and implementation framework to assess readiness for change and fit of the HPV Provider Communication intervention to the context of these clinics. MethodsLocal HPV-associated cancer and HPV vaccination rates were assigned to Practice-Based Research Network clinics using data from the Colorado Central Cancer Registry, the Colorado Immunization Information System, and the American Community Survey. Staff from 38 clinics located in areas with high numbers of adolescents not up-to-date for HPV vaccine and high rates of HPV-associated cancers were recruited for qualitative interviews. Interview questions used the Promoting Action on Research Implementation in Health Services (PARIHS) conceptual framework and addressed the proposed intervention, current vaccination practices and prior quality improvement (QI) experience. ResultsTwenty-seven interviews were completed with clinicians, clinic managers, and other staff across 17 clinics (9 pediatric, 5 family medicine, 3 public/school-based health). Most clinics had some prior QI experience and there were few thematic differences between sites with more or less foundation for QI/immunization work. Participants were motivated to improve the health of their patients and valued both guidelines and local experience as important evidence to consider adopting an intervention. Interviewees were more interested in implementing the proposed intervention if it aligned with existing priorities and fit within clinic workflows. Facilitation needs included adequate time and external facilitation support for data tracking and analysis. ConclusionsQualitative interviews to understand clinic context and fit of an HPV Provider Communication intervention can inform implementation in settings with the highest potential for clinical impact.

Chemotherapy delivery in early-onset colorectal cancer is impacted by urban versus rural settings in Colorado.

19 Background: While colorectal cancer (CRC) incidence has been decreasing overall, incidence in adults under age 50 has been rising both nationally and across Colorado. National guidelines have adapted to recognize this trend, but knowledge gaps regarding early-onset CRC remain. This group has previously established rising early-onset CRC incidence in Colorado, as well as later stage at diagnosis and worse prognosis. This study examines demographics, treatment, survival, and concomitant disease among patients &lt; 50 and diagnosed with CRC across a multicenter healthcare system in Colorado in order to better understand early-onset CRC. Methods: We analyzed 1,192 CRC cases in patients &lt; 50 from the Colorado Health Data Compass database and cross-referenced these cases with the Colorado Central Cancer Registry to examine for association of gender, race/ethnicity, BMI, zip code, insurance type, stage, and concomitant medical conditions with overall survival and oncologic treatment modality. Logistic regressions were used to evaluate the relationships between chemotherapy and the important variables while adjusting for covariates, with 95% confidence intervals reported. Cox proportional hazard regressions were used to evaluate the relationships between overall survival and the important variables while adjusting for covariates, with 95% confidence intervals reported. Results: Overall, early-onset CRC in our population was 2.8% stage I, 6.3% stage II, 12.7% stage III, 18.5% stage IV, and 59.8% were unstageable or no stage recorded. Surgical treatment was associated with a 52% improvement in overall survival. Chemotherapy treatment was not associated with any survival changes in stage II disease. Radiation treatment, insurance type, number of concomitant conditions, geographic location, and race/ethnicity were not associated with overall survival. Upon exploring chemotherapy relationships, patients from urban areas were significantly more likely to receive chemotherapy than patients from rural areas, while adjusting for ethnicity, inpatient encounters, and stage (OR 5.55, p = 0.001). Conclusions: While less is known about CRC in patients &lt; 50, trends are emerging that are not as well described in a traditional CRC population. The difference between urban and rural patients and their rates of chemotherapy points to a potential disparity in access to care, particularly when considering advanced stage CRC. This persisted through insurance type, indicating that distance from an infusion center, rather than ability to pay, is more likely to be driving this relationship. Further research is needed to determine if these findings are generalizable to the larger early-onset CRC population, and how access may be affecting care for this population.

Cancer Treatment Data in Central Cancer Registries: When Are Supplemental Data Needed?

Background:We evaluated treatment concordance between the Colorado All Payer Claims Database (APCD) and the Colorado Central Cancer Registry (CCCR) to explore whether APCDs can augment registry data. We compare treatment concordance for breast cancer, an extensively studied site with an inpatient reporting source and select leukemias that are often diagnosed outpatient.Methods:We analyzed concordance by cancer type and treatment, patient demographics, reporting source, and health insurance, calculating the sensitivity, specificity, positive predictive values (PPV) and Kappa statistics. We estimated an adjusted logistic regression model to assess whether the APCD statistically significantly reports additional cancer-directed treatments.Results:Among women with breast cancer, 14% had chemotherapy treatments that were absent from the CCCR. Missing treatments were more common among women younger than age 50 (15%) and patients aged 75 and older (19%), rural residents (17%), and when the reporting source was outpatient (22%). Similar and more pronounced patterns for people with leukemia were observed. Concordance for oral treatments was lower for each cancer. Sensitivity and PPVs were high, with moderate Kappa statistics. The APCD was 5.3 percentage points less likely to identify additional treatments for breast cancer patients and 10 percentage points more likely to identify additional treatments when the reporting source was an outpatient facility.Conclusion:A robust data infrastructure is needed to investigate research questions that require population-level analyses, particularly for questions seeking to reduce health inequity and comparisons across payers, including Medicare Advantage and fee-for-service. APCD data are a step toward creating an infrastructure for cancer, particularly for patients who reside in rural areas and/or receive care from outpatient centers.

The role of all-payer claims databases to expand central cancer registries: Experience from Colorado.

To evaluate the quality of a multiyear linkage between the Colorado all-payer claims database (APCD) and the Colorado Central Cancer Registry. Secondary 2012-2017 data from the APCD and the Colorado Cancer Registry. Descriptive analysis of the proportion of cases captured by the linkage in relation to the cases reported by the registry. We used probabilistic linkage to combine records from both data sources for all patients diagnosed with cancer. We successfully linked 93% of the 146,884 patients in the registry. Approximately 63% of linked patients were perfect matches on five identifiers. Of partial matches, 81.6% were matched on four identifiers with missing or partial Social Security Numbers. The linkage rate was lower for uninsured patients at diagnosis (74.7%) or patients with private plans (89.4%) but close to 100% for Medicare and Medicaid enrollees. Most of the 29% of patients who did not have claims at the time of diagnosis were covered by private plans that may not submit claims. APCD-registry linkages are a promising source of data to conduct population-based research from multiple payers. However, not all payers submit claims, and the quality of the data may vary by state.

Pediatric melanoma: Characterizing 256 cases from the Colorado Central Cancer Registry.

Melanoma is a rare diagnosis in the pediatric population. Differences in incidence, presentation, and survival distinguish pediatric melanoma from adult melanoma. In order to improve our understanding of pediatric melanoma, our case series investigates differences in incidence, age of onset, and anatomic site between male and female pediatric melanoma patients in Colorado between 1988 and 2015. All data were gathered from the Colorado Central Cancer Registry. A request for de-identified data on pediatric melanoma patients between 1988 and 2015 was made by the University of Colorado Department of Dermatology. Chi-square tests were used to compare the differences reported in melanoma between sex, age-groups, and site of lesion. A total of 256 cases of melanoma were reported in Colorado in patients <20years of age between 1988 and 2015. Overall incidence of pediatric melanoma in Colorado increased from 1988 to 1999 but declined from 2001 to 2011. There was a significant predominance of female cases in the 10-14 age-group (P=0.0477) and 15-19 age-group (P=0.0472). Both groups had increased incidence of melanoma with increasing age. The mean age of onset for both sexes was 16years old. Boys were more likely to have melanoma of the scalp and neck (P=0.0523) and less likely to have melanoma of the leg (P=0.0049). Among the pediatric population, girls 10-14 and 15-19years old are at a significantly increased risk of melanoma compared to boys in these age-groups. Our study found sex-specific differences in anatomic site consistent with prior literature. Further investigations should aim to identify causes for these sex-specific differences in order to better guide public health initiatives.

The impact of young adult colorectal cancer: incidence and trends in Colorado

Aim: Far less is known about colorectal cancer (CRC) incidence in individuals under the age of 50. This study examined CRC incidence in order to better understand the changing CRC population. Methods: This study analyzed 39,525 CRC cases from the Colorado Central Cancer Registry from 1992 through 2013. Age-adjusted incidence, observed and relative 5-year survival, and estimated annual percentage change was analyzed. Results: Age-adjusted rates averaging 1.7% per year were observed in the under-50 population, while falling on average 4.3% per year (p &lt; 0.05) in the over-50 population. Average-adjusted incidence rose in males under 50 by 2.7% per year (p &lt; 0.05). Conclusion: The absolute incidence of CRC continues to fall in Colorado, however incidence is rising in individuals under 50, particularly males.

Prevalence and Predictors of Distress in Posttreatment Adult Leukemia and Lymphoma Survivors

This paper examines predictors of cancer-specific distress among posttreatment adult leukemia and lymphoma survivors (LLS). Using a survey mailed to LLS in the Colorado Central Cancer Registry (N = 477), the authors developed a multivariable risk profile for distress. Thirty one percent of LLS reported indicators of distress. Significantly higher distress was associated with younger age (p < 0.001) in bivariate analyses. The risk profile included fear of recurrence, financial burden, and younger age. Distress did not attenuate based on time since treatment completion and may persist up to 4 years posttreatment, suggesting a need for intervention, particularly among high-risk LLS.

A novel approach to increase awareness about hereditary colon cancer using a state cancer registry

PurposeThe aim of this project was to conduct educational outreach about hereditary colon cancer to a targeted high risk population identified through a state cancer registry. MethodsIndividuals who met one of the first three Bethesda criteria guidelines were identified through the Colorado Central Cancer Registry. The physician of record received a brochure, survey and form to provide written consent to contact patient(s). Cases were mailed an educational brochure, initial and follow-up survey. ResultsFive hundred seventy-five cases and 412 physicians were identified; 81% provided consent. Ninety percent of physicians felt the registry should provide this information to at-risk patients. Twenty-three percent of the cases returned the survey. Cases were generally glad to get the information. Only four cases reported concern. The majority agreed the cancer registry should send the information, however most preferred their physicians be consented first. At follow-up, 20 cases reported having or intending to have a risk assessment. ConclusionsResponse from physicians and cases was positive, suggesting that targeted outreach using cancer registries, in combination with physician notification, may be a viable approach to educational outreach about cancer genetics. A proportion of cases sought risk assessment, suggesting that mail-based outreach may be effective in increasing uptake of information and/or genetic services.

The anatomic distribution of melanoma and relationships with childhood nevus distribution in Colorado

The nature of the relationship between nevus development in childhood and later development of melanoma is unclear. Data on melanoma diagnoses by histologic type and anatomic site were obtained for 2351 white, non-Hispanics in Colorado from the Colorado Central Cancer Registry between 2000 and 2004. Nevus size and body site were ascertained during skin exams conducted in the summer of 2007 on 717 white, non-Hispanic children aged 8-9 years. Chi-square goodness-of-fit analysis was used to assess the association between the anatomic site distributions of nevi versus melanoma. Superficial spreading melanoma was the most frequent histology, followed by lentigo maligna melanoma. Nodular melanoma was the least common histology. For males, there was no significant difference between the distribution of medium-sized (> or =2 mm) nevi and the distribution of both superficial spreading and nodular melanomas. For females, there was no significant difference between the anatomic distribution of small-sized (<2 mm) nevi and the distribution of nodular melanoma, and there was marginal evidence for a difference between the distribution of medium-sized (> or =2 mm) nevi and the distribution of nodular melanoma. There was evidence for a difference between all of the nevus distributions and the distributions of superficial spreading and lentigo maligna melanoma in females. The similarities between the nevus and melanoma distributions are interesting findings, but it is difficult to interpret the significance of these findings based on the current state of knowledge of melanoma etiology.

Abstract PR-10: Poverty, insurance status, and colorectal cancer in Colorado: 1995-2006.

Abstract PR-10 Background Poverty in Colorado is an important factor that lowers the advantages of being diagnosed with colorectal cancer (CRC) at the earlier stage of disease and decreases survival due to CRC. Health insurance status can also lead to disparities in early detection of CRC. Methods Data from the Colorado Central Cancer Registry in the Colorado Department of Public Health and Environment and information from the 2000 U.S. census were used to determine the proportions of Colorado residents with CRC residing in areas designated as “less than 10% poverty” or wealthier areas, “10-19% poverty” or middle poverty areas, and “20+% poverty” or poorest areas. Since income was not reported to the cancer registry, the poverty level of the census block group area, obtained through the 2000 U.S. Census, where each cancer case resided was used to assign the poverty level for that case. The analyses presented included CRC cases over a 12-year period, from 1995-2006, in order to compare early stage diagnosis by area poverty level and age (less than 65 vs. 65 and older). Early stage at CRC diagnosis and insurance status by area poverty level for 1998-2006 and five-year cause-specific survival among Colorado CRC cases from 1999-2002 were also analyzed. Results Among the 21,212 colorectal cancer cases reported to the cancer registry from 1995-2006, 64.5% resided in wealthier areas, 24.8% were from middle poverty areas, and 10.7 % were from the poorest areas of the state. The proportion of early stage diagnosis was lower among the CRC cases from the poorest areas (42.0%) compared to those from the wealthier areas (44.2%). Among those less than aged 65, there was a substantial decrease in early stage at CRC diagnosis as poverty level increased (42.0% from wealthier areas vs. 37% from poorest areas). This is in contrast to those aged 65 and older (45.5% from wealthier areas vs. 44.4% from the poorest areas). In addition, of those younger than age 65 whose insurance status was available from the cancer registry for 1998-2006 (n=5,288), having no insurance or only Medicaid coverage was a disadvantage for early stage diagnosis compared to those with private insurance in all three poverty groups. More importantly, five-year cause-specific survival decreased as poverty level increased (64.1% from wealthier areas, 58.1% from middle poverty areas, 50.8% from the poorest areas of the state). This association between survival differences and socioeconomic status was apparent in those younger than 65 (67.8%, 66.9%, 48.7%) and in those 65 and older (61.5%, 53.9%, 51.9%). Conclusions Poverty and lack of health insurance are disadvantages that lead to disparities in early detection of and survival from colorectal cancer. Citation Information: Cancer Prev Res 2008;1(7 Suppl):PR-10.

The impact of physical and psychosocial factors on work characteristics after cancer

Most previously employed cancer survivors continue to work after treatment, but the impact of cancer symptoms or psychosocial concerns on their work has seldom been assessed. We conducted a community-based survey of cancer survivors from the Colorado Central Cancer Registry to assess the changes in their work and the demographic, clinical, and psychosocial characteristics associated with work changes over the 2 years following diagnosis. Of 100 survivors, 92 returned to work, but 57% of those reduced their work by more than 4 h/week, and 56% noted a change in some aspect of their occupational role. Physical symptoms, particularly lack of energy or nausea/vomiting, and psychological symptoms, particularly feeling bored or useless or feeling depressed, were significantly associated with a reduction in work hours or a change in occupational role. Since changes in work are common and are associated with both physical and psychosocial symptoms, strategies are needed to reduce symptom burden and barriers to work and to improve work capacity for working-age cancer survivors.

Physician sex and other factors associated with type of breast cancer surgery in older women.

Physician-related factors as well as patient characteristics may explain why women aged 65 years or older with early-stage breast cancer undergo lumpectomy less often than younger women, despite National Institutes of Health recommendations favoring lumpectomy over mastectomy. A descriptive and analytical retrospective computer-assisted telephone survey. A population-based random sample of breast cancer survivors in Colorado, identified from the Colorado Central Cancer Registry. Women aged 65 to 84 years when diagnosed as having stage I or II breast cancer, treated 1 to 6 years previously with mastectomy or lumpectomy, and without recurrence or second primary cancers. Among women contacted, 58% participated. Results of 198 interviews are reported. Survey questions included patient decision-making participation and physician recommendations, sources and amount of treatment information provided by physicians, physician characteristics, and patient surgery preferences and demographic characteristics. A multivariate logistic regression model identified factors independently associated with lumpectomy. Lumpectomy was strongly associated with higher patient education, female physician sex, patient age 75 years or older, and amount of physician-provided information. The number of physician-provided information sources was associated with surgery explanations, and female physicians provided more sources of information. A physician decision or recommendation for surgery type was reported by 61% of women, of whom 93% underwent the recommended procedure. A subset of patients (13%) reported deferring the surgery decision to someone else. These results suggest that better-educated and better-informed older women are more likely to undergo lumpectomy, and that physicians may influence breast cancer patients' decisions about surgery type.

Alteration of the p53 Tumor Suppressor Gene and Activation of c-K-ras-2 Protooncogene in Endometrial Adenocarcinoma From Colorado

The authors previously reported a significant frequency of activating point mutations in codon 12 and 13 of the K-ras gene in endometrial carcinoma and endometrial atypical hyperplasia from Osaka, Japan. They also showed that alterations of the p53 gene are found frequently in those tumors. This study was designed to reveal possible demographic differences in the prevalence of K-ras and p53 mutations in endometrial carcinoma. Tumor-enriched areas of paraffin-embedded histologic sections obtained through the Colorado Central Cancer Registry were isolated and extracted for DNA. Fragments amplified by polymerase chain reaction (PCR) were screened for transforming mutations in codon 12, 13, or 59-63 of K-ras by direct sequencing. Of 38 endometrial adenocarcinomas that were analyzed, K-ras activation was detected in 4 cases (11%), three in codon 12 (a single case with a GGT-->AGT transition, a single case with a GGT-->GAT transition, and a single case with a GGT-->TGT transversion) and one in codon 13 (a GGC-->GAC mutation). The prevalence of K-ras mutations was significantly lower in endometrial carcinomas from Colorado (4 of 38, 11%) than in those from Osaka, Japan (17 of 57, 31%; P = .02). Mutations in exons 5-8 of p53 were screened by PCR-SSCP analysis, and subsequently confirmed by direct sequencing. Mutations in the p53 gene were detected in 5 of 38 endometrial carcinomas from Colorado (13%), including a single base substitution mutation in 3 cases (60%) and a deletion mutation in 2 cases (40%). Mutations in the p53 gene were significantly more frequently found in G3 cancers (3 of 7, 43%) than G1-G2 cancers combined (2 of 31, 6%; P = .025). Although the prevalence of p53 mutations in endometrial carcinomas from Colorado was not significantly different compared to that from Osaka, Japan (9 of 40, 23%), a G:C-->A:T transition at a CpG site, which was the most common base substitution mutation among Japanese, was not included in any tumors from Colorado. A rare polymorphism in codon 213 (CGA-->CGG) was observed in three cases. These observations may indicate that genetic or environmental factors may significantly influence the pathway of endometrial carcinogenesis.

Laryngeal cancer in Colorado.

Previous studies of laryngeal cancer have shown a decrease in the male-to-female ratio and that the sex ratio in glottic tumors is higher than that for other laryngeal sites. The purpose of this study was to characterize and identify changes in the demographics, laryngeal site predilection, geographic distribution, trends in tumor stage at diagnosis, and surgical caseload distribution in Colorado. The Colorado Central Cancer Registry for the years 1979 to 1990 was reviewed for cases of laryngeal cancer. The data were analyzed using chi-square and gradient-in-proportions methods. One-thousand two-hundred sixty-five (1265) cases were identified with a male-to-female ratio of 4.3:1. There was a significant trend of an increasing proportion of cases attributable to women. Glottic carcinoma accounted for 50.1% of cases, with a male-to-female ratio of 7.6:1. The Denver metropolitan area accounted for 57% of all cases, which was not disproportionate to the population. From 1981 to 1990 there was a significant decrease in the proportion of stage I cases and an increase in stage II cases. The teaching hospitals associated with the University of Colorado were responsible for performing 44.5% of all surgery for laryngeal cancer. The results indicate that laryngeal cancer in Colorado shares similar epidemiologic characteristics to those reported in other studies. Of most concern is the increasing proportion of women with laryngeal cancer and the decrease in cases diagnosed at stage I.

Are modified radical mastectomies done for T1 breast cancers because of surgeon's advice or patient's choice?

Clinical trials show that T1 breast cancers are equally well treated with breast-conserving surgery as with modified radical mastectomy. However, the Colorado Central Cancer Registry indicates that, for the past 5 years, the majority of women (72%) with T1 breast cancer in Colorado have undergone modified radical mastectomies. A questionnaire was sent to 175 general surgeons to determine the reasons for the high number of modified radical mastectomies still being performed. The results indicate that one group of surgeons (34% of those responding) believes each type of surgery has equal survival rates but unknowingly influences the patient to choose modified radical mastectomy, with a subtly biased presentation. Education of both surgeons and patients is needed to increase the number of patients with T1 breast lesions who can benefit from breast-conserving therapy.

Evaluation of Prostatic Cancer Histology and Grade Distribution: Experience With the Colorado Central Cancer Registry

Although well-defined grading schemes for prostatic adenocarcinoma have been developed, they are not yet universally accepted by practicing surgical pathologists. The complexity of these schemes often leads surgical pathologists to develop their own modified Broders scheme. This study compared the grade distribution as obtained by a community of surgical pathologists with that obtained using the National Prostatic Cancer Project (NPCP) and Gleason grading schemes. In 1978, 308 cases of prostate cancer were reported to the Colorado Central Cancer Registry (CCCR) from the Denver Standard Metropolitan Statistical Area. Two hundred eighteen of these cases were regraded. The grade distribution as reported by the CCCR revealed a predominance of low-grade tumors (grade I-41%, grade II-28%, grade III-17%, grade IV-3%). Regrading of these same cases revealed a shift to higher grades (NPCP: grade I-14%, grade II-11%, grade III-37%, grade IV-29%; Gleason: pattern scores less than 6-30%, score 6-24%, score 7-12%, score 8-11%, score 9-10%, score 10-4%). Twenty-one cases of histologic variants which were not originally diagnosed were also noted (six mucinous, 12 ductal, two endometroioid, one squamous). There were 18 cases in which no evidence of carcinoma was confirmed. These results suggest that there is a tendency to underestimate grade and potentially malignant behavior when well-defined prostatic cancer grading schemes are not applied.

Risk factors for adenocarcinoma of the lung.

The relation between various risk factors and adenocarcinoma of the lung was evaluated in a case-control study. Subjects were selected from the Colorado Central Cancer Registry from 1979-1982 in the Denver metropolitan area. A total of 102 (50 males and 52 females) adenocarcinoma case interviews and 131 (65 males and 66 females) control interviews were completed. The control group consisted of persons with cancers of the colon and bone marrow. The risk estimates associated with cigarette smoking were significantly elevated among males (odds ratio (OR) = 4.49) and females (OR = 3.95) and were found to increase significantly (p less than 0.01) with increasing levels of cigarette smoking for both males and females. For adenocarcinoma in females, the age- and smoking-adjusted odds ratios at different levels of passive smoke exposure followed an increasing overall trend (p = 0.05). After additional adjustment for potential confounders, prior cigarette use remained the most significant predictor of risk of adenocarcinoma among males and females. Analysis restricted to nonsmoking females revealed a risk of adenocarcinoma of 1.68 (95% confidence interval (Cl) = 0.39-2.97) for passive smoke exposure of four or more hours per day. Neither sex showed significantly elevated risk for occupational exposures, although males bordered on significance (OR = 2.23, 95% Cl = 0.97-5.12). The results suggest the need to develop cell type-specific etiologic hypotheses.