The authors report on a total of 199 consecutive patients diagnosed with pure DCIS treated with nipple-sparing mastectomy and immediate breast reconstruction. All patients in the cohort underwent both a frozen section and permanent section showing no evidence of tumor in the retroareolar resection margin. Over 90% of the patients had sentinel node biopsies, and none were positive on frozen section. Fifteen patients and adjuvant hormonal therapy and no patient had radiation therapy before locoregional recurrence. Sixty-five percent of patients had flap reconstruction, and 35% had reconstruction with implant or expander.
Only 5% (10 patients) had a locoregional recurrence. Of these, 6 patients had an invasive recurrence. Of the 10 patients, 5 had isolated nipple recurrence (2.5% of the total). At 10 years, the locoregional recurrence rate was 4.5%, and the nipple recurrence rate was 3%. The overall survival for the entire cohort of patients was 98.5%. The average time to local recurrence was 47 months. All patients with locoregional recurrence underwent wide local excision. The one patient who succumbed to disease presented with bilateral axillary metastases and simultaneous nipple recurrence dying with metastatic disease to the lung.
When the researchers applied univariate analysis to the study, the factors found to increase locoregional, and nipple recurrence included the following: tumor size greater than or equal to 4 cm, high nuclear grade, negative estrogen receptor status (ER), negative progesterone receptor status (PR), and Her2 positive status. When using multivariate analysis, only negative progesterone receptor status was significant with 4 cm or greater tumor size, almost reaching significance. Because the number of recurrences were small it was difficult to evaluate tumor to nipple distance as a risk factor for local recurrence. Nonetheless, they found no statistical difference in recurrence for tumors greater than or less than 1 mm from the nipple.
In summary, this study showed that the incidence of sentence structures locoregional recurrence in patients undergoing nipple-sparing mastectomy for pure DCIS was quite low. In examining the entire cohort, the 10 – year local recurrence rate was only 4.5%, and the nipple recurrence rate was also low at 3%. The researchers found that tumors greater than or equal to 4 cm, high nuclear grade, ER-negative status, PR- negative status, and Her2 positive status all impacted the risk of recurrence. When multivariate analysis was applied, only negative progesterone receptor status reached significance.