[Clinical characteristics and prognosis of patients with ipsilateral breast tumor recurrence after breast conservation therapy].

Objective: To analyze the clinical features and prognosis of the ipsilateral breast tumor recurrence (IBTR) after breast conserving surgery. Methods: From 1999 to 2013, 63 women with IBTR after breast conserving surgery were retrospectively reviewed. All patients had adequate information on tumor location both at first presentation and at recurrence, with or without regional recurrence or distant metastasis. The histologic changes between true local recurrence and elsewhere recurrence groups were compared. The local recurrence, the overall survival after IBTR (IBTR-OS), the disease-free survival after IBTR (IBTR-DFS) were also compared. Results: All patients had undergone lumpectomy, including 38 cases with additional axillary lymph node dissection and 13 cases with sentinel lymph node biopsy. There were 11.3% (7/63) cases received neoadjuvant systemic therapy, 68.3% (43/63) had adjuvant radiotherapy, 60.3% (38/63) underwent adjuvant chemotherapy and 47.6% (30/63) received hormonal therapy. Forty-five cases (71.4%) had recurrence in the same quadrant, and 18 cases (28.6%) had elsewhere recurrence. Compared with histology at presentation, 10.3% of the patients (6/58) had different ones at recurrence and 28.9% of patients (13/45) had different molecular subtypes. The conversion rate of estrogen receptor status (33.3% vs 9.5%, P=0.012) and progesterone receptor status (56.3% vs 19.0%, P=0.005) in patients with elsewhere recurrence was significantly higher than that in patients with same quadrant recurrence. Fifty-nine cases had undergone surgery after IBTR, with 48 cases of secondary breast-conserving surgery and 11 cases of salvage mastectomy. The median time to IBTR of same quadrant recurrence and elsewhere recurrence groups were 26 months and 62 months (P=0.012), respectively. There were 84.4% and 44.4% cases who had local recurrence within 5 years after breast conserving surgery, respectively. Of all cases, the overall 5-year IBTR-OS and 5-year IBTR-DFS rates were 79.4% and 60.4%, respectively. There were no significant differences in 5-year IBTR-OS (77.4% vs. 83.6%, P=0.303) or 5-year IBTR-DFS (60.0% vs. 62.8%, P=0.780) between same quadrant recurrence and elsewhere recurrence groups. Univariate analysis showed that pN0-1 (P<0.001), luminal subtype (P=0.026), adjuvant endocrine therapy (P=0.007) at first presentation, recurrent tumor < 3 cm (P=0.036) and having surgery after IBTR(P=0.002) were favorable factors of IBTR-OS. pN0-1 (P<0.001) at first presentation, recurrent tumor stage Ⅰ-Ⅱ (P<0.001) and having surgery after IBTR(P=0.001) were favorable factors of IBTR-DFS. There was no significant difference between second breast-conserving surgery and salvage mastectomy in IBTR-OS and IBTR-DFS (P>0.05). Conclusions: The IBTR after breast conserving surgery mainly occurred at the original quadrant. Second breast-conserving surgery did not affect patient's prognosis. There were significant differences in biological features between the same quadrant recurrence and elsewhere recurrence, requiring different therapeutic strategies in the future.