Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease.

Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58,515 women with invasive breast cancer and 95,067 controls from 53 studies.

The development of radiotherapy in Slovenia.

The historical data on the development of radiotherapy in Slovenia are presented from its first use in this county in 1902 until the present. The Institute of Oncology in Ljubljana was established in 1938 with the intention of providing a sound development of radium and roentgen cancer treatment. After World War II, the development of radiotherapy was dynamic, which is evident from the data on new radiation sources in external beam therapy (accelerators, telecobalt units), in brachytherapy (various sealed radioisotopes) as well as in the introduction of therapy with unsealed radioisotopes.

Breast-cancer risk and oral contraceptive use in Slovenian women aged 25 to 54.

Results of a previous case-control study in Slovenia showed a significantly elevated risk of breast cancer for ever-OC users aged 25 to 54 years. A further study was conducted in 1988-1990 in the whole of Slovenia, employing more rigorous epidemiological methodology. Cases were 624 women with breast cancer, aged 25 to 54 years, diagnosed at the Institute of Oncology in Ljubljana and other Slovenian hospitals.

A case-control study of breast cancer in relation to oral contraceptive use in Slovenia.

With the aim to investigate a possible association between oral contraceptive (OC) use and breast cancer occurrence, 534 women aged 24--54 years with newly diagnosed breast cancer and 1989 individually matched hospital controls were interviewed during 1980--1983. The overall risk for ever-users vs. never-users estimated by logistic regression and adjusted for several possible confounding factors was 1.

Age at any birth and breast cancer risk.

In an effort to assess the relative importance of age at first birth, age at subsequent births, and total parity to the occurrence of breast cancer, reproductive data from 4,225 women with breast cancer and 12,307 hospitalized women without breast cancer were analyzed by a multiple logistic regression model. Age at first birth was confirmed to be the most important reproductive risk indicator; it was associated with a 3.5% increase of relative risk for every year of increase in age at first birth (the 95% confidence interval of this estimate was 2.