Multiple sclerosis and breast cancer.

Multiple sclerosis (MS) and breast cancer (BC) share common features; most notably, both are more frequent in women than in men. In addition to the involvement of sex hormones, a number of genetic and pharmacological studies support a possible relationship between these two diseases. However, there are no conclusive epidemiological findings related to MS and BC worldwide, and there are no recent data for the US population. We conducted a case-control study using a hospital inpatient discharge dataset (21,536 cases and two control series totaling 59,581 controls) from the Texas Health Care Information Collection. We assessed occurrence of MS in BC cases and in two control series: diabetes mellitus type II, and open wounds. After controlling for age, race-ethnicity, and health insurance status, a statistically-significant protective association was detected: BC cases were 45% less likely than diabetic controls to have MS (OR=0.55, 95% CI=0.37-0.81), and 63% less likely than open wound controls to have MS (OR=0.37, 95% CI=0.21-0.66). Our study presented here is the only current assessment of the association between MS and BC in the USA and suggests a protective effect of MS on BC in the hospitalized population.

Spline regression in clinical research / La regresión por spline en la investigación clínica

OBJECTIVE: The objective of this article is to illustrate the statistical technique of spline regression, an under-utilized tool in clinical research. Spline regression was used to assess the dose-response association between serum albumin and hospital mortality. METHODS: Data from a previous study of patients hospitalized throughout Florida, United States of America (U.S.A.), for invasive group A streptococcal disease were accessed. For the current analysis, serum albumin (SA) at the time of admission was the risk factor of interest. The outcome was unadjusted hospital mortality among 117 patients. First, a traditional, suboptimal approach was employed by breaking SA into three groups and calculating the crude hospital mortality rate in each SA category. The second approach involved the creation of a curve using a quadratic spline model. RESULTS: The traditional approach yielded only three points of information: the hospital mortality rate for the three SA groups. Among patients whose SA upon admission was < 2.5 g/l00 mL, 2.5 to 3.4, and 3.5 or greater, the hospital mortality rate was 40.7, 14.8, and 8.3, respectively. The spline model, however, resulted in a smooth curve which was more clinically plausible. CONCLUSION: The goal of this paper is to expose clinicians to splines. Spline regression, unlike categorical analysis, does not impose the unrealistic assumption of a homogenous risk within categories. Another disadvantage of categorical analyses is that they allow large changes in risk between categories...

Primary malignancies of the thyroid: epidemiologic analysis of the Florida Cancer Data System registry.

PURPOSE: Descriptive epidemiology of thyroid cancer in Florida. METHODS: The Florida Cancer Data System (FCDS) registry was used to identify patients with the different histologic subtypes of thyroid cancer occurring in Florida from 1981 through 1993. RESULTS: The FCDS recorded 5746 primary malignancies of the thyroid. The average annual incidence of all types of thyroid cancer was 37.0 cases/1,000,000 population. One type of thyroid cancer (papillary carcinoma) accounted for the overall increase during the 13 years of this study. There was no difference in incidence based on Hispanic ethnicity, but the incidence in Blacks was half that of Whites, and Blacks showed less advanced disease at the time of diagnosis. CONCLUSIONS: The increase in incidence of only one histologic type of thyroid cancer suggests that the increasing rate is not an artifact related to the utilization of new diagnostic technologies. The lower incidence and tendency to have less advanced thyroid cancer in Blacks would indicate that racial differences in thyroid cancer are not likely explained by socioeconomic factors such as access to medical care. A substantial amount of the difference in incidence between Whites and Blacks is explained by differences in age distribution.

Malignant tumors of the eyelid: a population-based study of non-basal cell and non-squamous cell malignant neoplasms.

OBJECTIVE: To determine the relative frequencies, average annual incidences, and patient characteristics of non-basal cell and non-squamous cell malignant neoplasms of the eyelid in a defined geographic population. DESIGN AND SETTING: A retrospective study using the Florida Cancer Data System to identify malignant tumors of the eyelid, except for basal cell and squamous cell carcinomas, from 1981 through 1994. Cases were limited to persons who resided within Florida. MAIN OUTCOME MEASURE: Incidence of histologically confirmed malignant eyelid tumors. RESULTS: Two hundred six primary malignant eyelid tumors were identified. The 3 most common, in order of frequency, were melanoma, sebaceous carcinoma, and lymphoma. The median age at diagnosis for all patients was 73 years. Only 3 of the 206 malignant neoplasms occurred in blacks. The annual incidence of eyelid melanoma and sebaceous carcinoma in whites older than 20 years was 0.6 and 0.5 per million, respectively. Kaposi sarcoma was the most common type of mesenchymal tumor. Eleven different histologic types of lymphoma were found in the eyelid. Only 2 of 27 lymphomas had T-cell lineage. CONCLUSIONS: Malignant tumors of the eyelid other than basal cell and squamous cell carcinoma are uncommon and usually occur in elderly white persons. Primary eyelid tumors of any type are rare in blacks. The risk of a non-basal cell and non-squamous cell malignant neoplasm of the eyelid in Florida is 6.4 times greater for whites than for blacks (95% confidence interval [CI], 2.1-20.2). A variety of B-cell lymphomas can be manifested as primary eyelid tumors.

Malignant tumors of the orbit. Analysis of the Florida Cancer Registry.

PURPOSE: The purpose of the study is to determine the relative frequency and incidence of primary malignant tumors of the orbit occurring in Florida. METHODS: Cases of primary orbital malignancy were identified in the Florida Cancer Data System registry from 1981 through 1993. Analysis was restricted to persons who reside within the state. RESULTS: Three hundred fourteen primary orbital malignancies were reported; 55% of malignant orbital tumors were lymphoma. The average annual incidence for all malignancies was 2 cases per million. There was a steady increase in the annual incidence of orbital malignancy during the 13 years of the study. Lymphoma showed the greatest rise in annual incidence. The average annual incidence of lymphoma increased 166% the last 6 years of the study compared to the first 6 years. CONCLUSIONS: A large increase in orbital lymphoma was documented in the Florida cancer registry from 1981 through 1993. The increase in incidence cannot be explained by improved compliance in reporting or by the small increase in incidence of systemic lymphoma during the survey period. Additional studies are needed to determine whether the observed increase in incidence in orbital lymphoma is genuine or spurious.