DETERMINANT FACTORS BETWEEN MASTECTOMY AN D BREAST-CONSERVING TREATMENT IN THE FRENCH DEPARTEMENT OF COTE-DOR FROM 1982 TO 1990 - GYNECOLOGICAL-TUMORS-REGISTRY OF COTE-DOR

The aim of this study is to check, for a defined period and within a g eographic area, whether the increased use of breast conserving treatme nt was related to changes in tumor characteristics, or whether changes in therapeutical practice persisted after adjustment on patients and tumor characteristics. From 1982 to 1990 1,952 women with invasive car cinomas were registered in the French ''departement'' of Cote-d'Or. Se venteen hundred and seven non metastatic patients were treated by loco -regional surgery. A breast conserving surgery was performed in 60% of cases. The incidence of this treatment raised from 32% in 1982 to 73% in 1987. In univariate analysis, factors determining the type of tumo r excision were: age, hormonal status, tumor size, tumor location, ''c linical seriousness'', nodal status, multiple tumors, inflammatory tum ors, neoadjuvant treatments and year of diagnosis. Age and tumoral fac tors remained significant in a logistic regression analysis. Other fac tors being constant, the odds ratios of mastectomy was 12.9 times lowe r in 1987-1990 than in 1982, and 2.1 times lower than in 1985-1986, sh owing a ''period effect''. Ninety four percents of patients treated by breast conserving surgery were irradiated post operatively, showing t hat the clinical research recommendations were well transfered to the clinical practice in this department.