INFLUENCE OF LOCAL TREATMENT ON THE RECURRENCE RATE OF DUCTAL CARCINOMA IN-SITU

BACKGROUND: Screening mammography has resulted in a significant increa se in the diagnosis of ductal carcinoma in situ (DCIS). The role of br east conservation therapy and the long-term recurrence rate are still controversial. This article compares mastectomy, wide excision done, a nd wide excision with radiation as treatments for DCIS. STUDY DESIGN: One hundred twenty-four cases of DCIS were retrospectively reviewed an d were found to be pure DCIS by a senior pathologist. The mean age at diagnosis was 60 years (range, 33 to 81). Originally, 101 patients (81 percent) presented with calcification on mammogram, and 23 (19 percen t) presented with a palpable mass. Histologic data showed that 54 (44 percent) had noncomedo type lesions, 46 (37 percent) had comedo type, and 24 (19 percent) had unknown type DCIS. RESULTS Four of the 124 pat ients had a recurrence during a mean follow-up period of 43 months. Re currence is defined as any development of DCIS or invasive carcinoma i n the ipsilateral breast. There was one (1.3 percent) recurrence in th e 75 patients treated with mastectomy (an adenocarcinoma of the chest wall), which occurred at 59 months. Treatment was 5,750 cGy to the che st wall and the patient is free of disease 37 months postradiation. Th ere were three (II percent) recurrences at 14, 21, and 29 months, resp ectively, in the 28 patients treated with wide excision done. Ah three recurrences were found by calcifications on mammogram and all patient s had comedo type original lesions, Two recurrences were pure DCIS of the breast. Both patients were treated with mastectomy and are free of disease at 33 and five months, respectively. The third recurrence was an invasive colloid carcinoma of the breast. Treatment was a modified radical mastectomy; the patient is free of disease after 62 months. T here were no recurrences in the 21 patients who were treated with wide excision and radiation. Average total dose of radiation was 5,835 cGy (range, 4,500 to 6,480). CONCLUSIONS: The results of this study indic ate that both mastectomy and wide excision with radiation are associat ed with very low recurrence rates. Wide excision alone is associated w ith a higher recurrence rate. However, all recurrences were detected m ammographically and all lesions were salvaged by mastectomy. Therefore , the ultimate local control and survival rates were similar for al th ree modalities.