Cancer Risk Among Residents of Rhineland-Palatinate Winegrowing Communities - Recent Advances and Issues in Environmental Science - page 93

Cancer Registry Data
This study is based on cancer cases registered in the Rhineland-Palatinate cancer reg-
istry which covers a population of approximately 4,000,000 persons. We included all
malignant tumors plus benign brain and central nervous system (CNS) tumors and
brain and CNS tumors of uncertain behavior. Furthermore, we included malignant
bladder tumors plus carcinoma in situ and tumors of uncertain behavior of the blad-
der. Since January, 2000 all Rhineland-Palatinate physicians and dentists are legally
obliged to report incident cancer cases to the cancer registry. Therefore, all above
mentioned cancers diagnosed between 2000 and 2003 and reported until mid-2005
were included. The following items are registered: diagnosis (ICD-10); topography
and morphology (ICD-O-2); staging (TNM); incidence date; most valid basis of di-
agnosis; occasion of first detection; initial treatment; last occupation and longest held
occupation; and date and cause of death (where appropriate). Population figures and
data on area under wine cultivation were obtained from the statistical office of Rhine-
land-Palatinate.
Statistical Methods
Completeness of the Rhineland-Palatinate cancer registry varies with time, region,
physician's specialization and type of cancer. This had to be considered in our analy-
sis. Completeness is estimated by the ratio of reported cases to estimated cases for
Rhineland-Palatinate calculated from a national pooling of cancer registry data [21,
22]. In communities with a small area under wine cultivation, the completeness (ex-
cluding non-melanotic skin cancer) is about 80% in males and 79% in females. Con-
cerning lymphohaematopoetic malignancies, the completeness is considerably lower;
in communities with a small area under cultivation, only 62% of NHL in males and
64% in females are reported to the registry.
Primary “Internal” Analysis of Incidence Ratio—Ratios for Communities with
a Medium or Large Area Under Cultivation in Comparison with Communities
with a Small Area Under Cultivation
To account for regional variations in completeness, in our primary analysis communi-
ties with a small area under wine cultivation served as reference. Provided that the
completeness does not differ systematically between winegrowing communities with
a large area under cultivation and adjoining communities with a small area under cul-
tivation, this allows to calculate valid incidence RRs by Poisson regression.
Population fi gures are reported in 5 year age categories by the State Statisti-
cal Offi ce; due to small numbers, the use of a categorized age variable would have
caused numerical problems in the regression analysis. Instead, age was included as
a continuous variable in the regression analysis (mid-point of each age category).
Many factors, like sociodemographic, lifestyle and environmental factors, might
considerably differ between large cities and villages/small cities. Cities with more
than 100,000 inhabitants (Mainz, Ludwigshafen/Rhein, Koblenz, Kaiserslautern) were
therefore excluded from the analysis. Furthermore, we adjusted for rural (<5,000
inhabitants) versus urban (≥5,000 inhabitants) communities. The proportion