Prognostic factors in ductal carcinoma in situ of the breast: results of aretrospective study of 575 cases

Objective. Conservative treatment for ductal carcinoma in situ of the breas t exposes patients to the risk of infiltrating recurrence which can lead to metastasis. The primary purposes of this retrospective study were to evalu ate diagnostic and therapeutic methods over a 10-year period and to validat e prognostic factors. This information should greatly improve patient selec tion for conservative treatment or mastectomy. Study design. A multi-instit utional data base including 575 patients treated between 1983 and 1993 was established by combining data from 16 French institutions. Survival at 5 an d 7 years was studied as a function of various prognostic factors. Results. Recurrence-free survival at 7 years was 0.96 after modified radical mastec tomy and 0.83 after breast-conserving treatment and radiotherapy (P=0.003). Metastasis-free survival at 7 years was 0.99 after modified radical mastec tomy and 0.94 after breast-conserving treatment and radiotherapy (not signi ficant). No factor was predictive of local recurrence after mastectomy. Cli nical stage was the only; factor significantly correlated with metastasis a fter mastectomy. Recurrence-free survival after breast-conserving treatment with radiotherapy was significantly lower for patients with comedo carcino ma, multifocal lesions, or unclear resection margins, regardless of whether the histological type was comedo or non-comedo carcinoma. Metastasis-free survival was significantly lower for patients with multifocal lesions and f or patients with unclear margins after excision of comedo carcinoma. Conclu sions. Breast-conserving treatment with radiotherapy is a valid alternative to mastectomy. Patients must be selected carefully on the basis of morphol ogical criteria. Swift gains in therapeutic outcome can be obtained by stre ssing quality control at each stage of diagnosis and treatment. (C) 1999 El sevier Science Ireland Ltd. All rights reserved.