[The treatment of carcinoma in situ of the breast].

In reference to a series of 36 in situ breast carcinomas, the current therapeutic possibilities are considered: 8 lobular carcinomas in situ (LCIS) and 28 ductal carcinomas in situ (DCIS) were diagnosed between January 1985 and July 1988. These are infraclinical forms in 80% of the cases, representing 20% of the breast carcinomas treated during the same period of time. The natural history of carcinomas in situ is presented; LCIS rarely evolve toward an invasive carcinoma and they should not be considered as risk factors. DCIS evolve, after biopsy, toward an infiltrating ductal carcinoma in 26 to 28% of the cases. Axillary node invasion is present in 3% of the cases. After diagnostic biopsy of a LCIS, a subcutaneous mastectomy with prosthetic reconstruction will be offered only if there are bilateral foci or diffuse microcalcifications. Supervision will be recommended in all other cases. The results of the mastectomy-node excision procedure are well known for the LCIS: less than 5% recurrence and a mortality under 1.5%. The current tendency goes toward a limited surgical act: axillary dissection is discussed for small LCIS; lumpectomy is more and more advocated with long-term results still not well known; in case of lumpectomy, two prospective trials are currently in progress in the world, in order to assess the efficacy of radiotherapy.