Breast conservation has become well-established in the treatment of early mammary carcinoma. However, a standardised treatment modality has not emerged. We have analysed the data from 1,973 patients treated in three consecutive randomised trials by four different radiosurgical procedures: Halsted mastectomy, quadrantectomy plus radiotherapy, lumpectomy plus radiotherapy, and quadrantectomy without radiotherapy, to compare the outcomes of these procedures in terms of local recurrence rate and overall survival. Eligibility criteria were similar in the three trials, and comparability between the four subgroups was excellent. Median follow-up for all patients was 82 months. The annual rates of local recurrence varied markedly according to the treatment. Patients treated with Halsted mastectomy and quadrantectomy plus radiotherapy had low annual rates of local recurrence (0.20 and 0.46, respectively) while both lumpectomy plus radiotherapy and quadrantectomy without radiotherapy had significantly higher rates (2.45 and 3.28, respectively). Patients under 45 years of age had a much higher incidence of local recurrences, while in women over 55 years local recurrences were much less frequent. Overall survival curves were identical in the four groups of patients, so that the three breast conserving radiosurgical procedures had the same survival rates as Halsted mastectomy. However, local recurrence rates were markedly influenced by the treatment method, patient age and specific histological features.