title: [Should all younger patients with breast cancer be offered adjuvant cytotoxic chemotherapy?].
abstract: The aim of the study was to investigate whether young age at diagnosis is a negative prognostic factor in primary breast cancer and how stage of disease at diagnosis and treatment may influence such an association. It was conducted as a retrospective cohort study based on a population-based data-base of breast cancer diagnosis with detailed information on tumour characteristics, treatment regimens, and vital status and included 10,356 patients with primary breast cancer less than 50 years of age at diagnosis. The main outcome measures were relative risk of dying within the first ten years after diagnosis according to age at diagnosis, adjusted for effect of known prognostic factors and expected mortality. Overall, young patients with low risk disease who did not receive adjuvant treatment had a significantly increasing risk of dying with decreasing age at diagnosis (adjusted relative risk: 45-49 years: 1 (reference); 40-44 years: 1.12 (0.89-1.40); 35-39 years: 1.40 (1.10-1.78); < 35 years: 2.18 (1.64-2.89). However, a similar trend was not seen in young patients who received adjuvant cytotoxic therapy. We found the same difference as above when comparing women receiving no treatment with those receiving adjuvant cytotoxic therapy within strata of node negative patients and patients with the same tumour size. In conclusion, the negative prognostic effect of young age is almost exclusively seen in women diagnosed with low risk disease not receiving adjuvant cytotoxic therapy, whereas young women who receive adjuvant cytotoxic therapy have the same prognosis as middle-aged women. These results suggest that young women with breast cancer, on the basis of age alone, should be regarded as high risk patients and be given adjuvant cytotoxic therapy.
authors.affiliation: Afdelingen for epidemiologisk forskning, Statens Serum Institut, København.
authors.forename: N T
authors.initials: NT
authors.lastname: Kroman
authors.forename: M B
authors.initials: MB
authors.lastname: Jensen
authors.forename: J
authors.initials: J
authors.lastname: Wohlfahrt
authors.forename: H
authors.initials: H
authors.lastname: Mouridsen
authors.forename: P K
authors.initials: PK
authors.lastname: Andersen
authors.forename: M
authors.initials: M
authors.lastname: Melbye
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000601:surgery; D017024:Chemotherapy, Adjuvant; D003718:Denmark; D005260:Female; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D000970:Antineoplastic Agents
vernacular_title: Bør alle yngre mammacancerpatienter tilbydes adjuverende cytotoksisk kemoterapi?