Introduction. L'association cancer du sein et grossesse est un évènement rare, défini par la survenue d'un cancer du sein durant la grossesse ou durant l'année suivant l'accouchement. La prise en charge doit être effectuée par une équipe multidisciplinaire associant gynéco-obstétriciens et cancérologues.

Matériel et Méthodes. Il s'agit d'une revue de la littérature.

Résultats.

Conclusion. Les données de la littérature permettent aujourd'hui de répondre à un certain nombre de questions concernant le cancer du sein au cours de la grossesse et la grossesse après un cancer du sein. Ces cas doivent être gérés par des équipes multidisciplinaires, permettant de prendre en charge au mieux les dimensions carcinologique, obstétricale et psychologique de cette association difficile.

The association of breast cancer with pregnancy is rare. It is defined as the occurrence of breast cancer during pregnancy or during the year following delivery. Patient management must be ensured by a multidisciplinary team including gynecologists, obstetricians and clinical oncologists.

• Breast cancer associated with pregnancy: Between 0.2 and 3.8% of breast cancers diagnosed in France are associated with pregnancy, representing 250 to 300 cases annually. The most frequent forms in this setting are infiltrating ductal tumors. There is a higher frequency of inflammatory forms (14 to 28%), multifocal involvement and node involvement, and the histoprognostic grade is generally higher than in non pregnant women of the same age.
  • The diagnosis is based on clinical (routine breast examination during the first trimester of pregnancy), radiological (mammography and especially ultrasound) and histologic examination.
  • The maternal prognosis is influenced by the frequent diagnostic delay and the higher frequency of poor-prognosis forms in these young patients. The overall survival rate is reduced by 10 to 15% compared with non pregnant women with comparable tumors. The main foetal risks are linked to prematurity (usually iatrogenic) and hypotrophy.
  • Treatment must strike a balance between the need to treat the mother without delay, and the need to respect the foetus. Termination must not be systematically recommended, because it does not, in itself, improve the maternal prognosis. Treatment is based on surgery (always possible, except near term), radiotherapy (if possible, during the post-partum period), and chemotherapy (possible from the fourth month of pregnancy). Strict maternofetal monitoring is necessary. Breast-feeding is contraindicated.
• Pregnancy after breast cancer. This situation concerns a growing number women, as 10% of new cases of breast cancer in France affect women under 40. Adjuvant treatments of breast cancer can cause ovarian insufficiency, and the fertility rate after chemotherapy is estimated at approximately 8% before 40 years of age and 11% before 35. The occurrence of pregnancy after correctly treated good-prognosis breast cancer does not seem to worsen the prognosis. The optimal interval between breast cancer treatment and conception is controversial, ranging from one year for carcinoma in situ, to 3-5 years for invasive forms. These pregnancies must be planned: reliable contraception must be used until pregnancy is feasible, and women should be advised by a multidisciplinary team, mainly on the basis of initial prognostic factors.