Disease-Free Survival After Breast Conservation Therapy vs. Mastectomy of Patients with T1/2 Breast Cancer and no Lymph Node Metastases: Our Experience

Several retrospective analyses of large amounts of contemporary data have shown the superiority of breast conservative surgery (BCS) over mastectomy carried out in the early stage of breast cancer. The characteristics of the patients and cancers that are most likely to benefit from BCS remain unclear. In our work, we analyzed the disease-free survival (DFS) of a cohort of patients treated with BCS or mastectomy between 1995 and 2018 in our institute with pT1-2, pN0, or cM0 breast cancer. The DFS curves of patients treated with both mastectomy and quadrantectomy were compared in the different subsamples with respect to the clinical and histopathological characteristics. We identified 188 eligible patients treated with BCS and 64 patients treated with mastectomy. DFS was not found to be statistically higher in patients treated with BCS compared to those treated with mastectomy, who achieved a 5-year DFS of 89.9% vs. 81.3% and a 10-year DFS of 78.9% vs. 79.3%, respectively. No significant differences were detected for the DFS curves when patients were differentiated by the type of surgical treatment received, age, and the tumor histological characteristics. We verified a p-value just above the 10% significance threshold for patients with tumor dimensions between 20 mm and 50 mm and molecular sub-type Luminal B. In our experience, treatment with mastectomy is not associated with improved DFS compared to treatment with BCS in women with early-stage tumors.

Sentinel node involvement with or without completion axillary lymph node dissection: treatment and pathologic results of randomized SERC trial

Based on results of clinical trials, completion ALND (cALND) is frequently not performed for patients with breast conservation therapy and one or two involved sentinel nodes (SN) by micro- or macro-metastases. However, there were limitations despite a conclusion of non-inferiority for cALND omission. No trial had included patients with SN macro-metastases and total mastectomy or with >2 SN macro-metastases. The aim of the study was too analyze treatment delivered and pathologic results of patients included in SERC trial. SERC trial is a multicenter randomized non-inferiority phase-3 trial comparing no cALND with cALND in cT0-1-2, cN0 patients with SN ITC (isolated tumor cells) or micro-metastases or macro-metastases, mastectomy or breast conservative surgery. We randomized 1855 patients, 929 to receive cALND and 926 SLNB alone. No significant differences in patient’s and tumor characteristics, type of surgery, and adjuvant chemotherapy (AC) were observed between the two arms. Rates of involved SN nodes by ITC, micro-metastases, and macro-metastases were 5.91%, 28.12%, and 65.97%, respectively, without significant difference between two arms for all criteria. In multivariate analysis, two factors were associated with higher positive non-SN rate: no AC versus AC administered after ALND (OR = 3.32, p < 0.0001) and >2 involved SN versus ≤2 (OR = 3.45, p = 0.0258). Crude rates of positive NSN were 17.62% (74/420) and 26.45% (73/276) for patient’s eligible and non-eligible to ACOSOG-Z0011 trial. No significant differences in patient’s and tumor characteristics and treatment delivered were observed between the two arms. Higher positive-NSN rate was observed for patients with AC performed after ALND (17.65% for SN micro-metastases, 35.22% for SN macro-metastases) in comparison with AC administered before ALND.

EP.TH.531Occult breast cancer: Breast conservation or Mastectomy in terms of recurrence. A single center experience

Aim We sought to compare breast conservation therapy & mastectomy as treatment of occult breast cancer in terms of recurrence. Methods It is a retrospective cross sectional study conducted on patients diagnosed to have occult breast cancer and going for either breast conservation therapy or mastectomy at The Aga Khan University Hospital Karachi between January 200o to December 2018, patients will be divided into two groups, first group will be consisting of patients who underwent breast conservation therapy and 2nd one will be of patients who had mastectomy. Patients will be included by consecutive sampling technique. Hospital database will be used to identify patients and data collected on a self designed tool using files and electronic patient records. Patients in both groups will be followed to see local recurrence from date of diagnosis to 2 years post operatively in hospital data base and their files, and then their data will be compared with the reference studies reported in this article. Results Awaited as the study is ongoing. Conclusions Awaited as study is ongoing.

Usefulness of postoperative surveillance MR for women after breast-conservation therapy: Focusing on MR features of early and late recurrent breast cancer

Purpose To investigate the imaging characteristics of early and late recurrent breast cancer and the detectability of mammography, ultrasonography, and breast magnetic resonance imaging (MRI) in patients who underwent breast-conservation therapy (BCT). Materials and methods Total of 1312 women with 2026 surveillance breast MRI after BCT between January 2014 and September 2018 were studied. Early recurrence was defined as newly diagnosed breast cancer and/or axillary metastasis within 12 months of surgery. Late recurrence was defined as recurrence after 12months of surgery. We assessed the detectability of recurrent lesions in each postoperative imaging modality and evaluated characteristics of recurrent lesions on postoperative MRI by comparing early and late recurrence groups. Result Of the 2026 cases, 103 were confirmed as recurrent breast cancer by biopsy or surgery. Thirty-one cases were early recurrence, and 72 cases were late recurrence. MRI showed significantly higher detectability for recurrent lesions (102 cases, 99%) than mammography (59.4%, p < 0.001) or ultrasound (68.9%, p < 0.001), or both mammography and ultrasound (81.6%, p < 0.001). The recurrent lesions did not have typical malignant morphologic features, but variable features on MRI. However, early recurrent lesions showed fast enhancement in early dynamic phase regardless of the kinetic pattern of delayed dynamic phase; and late recurrence lesions showed early fast enhancement and delayed washout pattern. There were 19 cases which were not detected on mammography or ultrasound but could only be detected with MRI. Conclusion Postoperative breast MRI showed significantly higher detectability for recurrent lesions than mammography and ultrasound. Early fast enhancement is the most important feature of recurrent lesions on postoperative breast MRI for both early and late recurrence groups. Due to its high possibility of recurrence, further work-up should be considered regardless of their morphologic features.

Does timing of chemotherapy impact breast satisfaction after breast conservation therapy and mastectomy with immediate reconstruction?

589 Background: Receipt of chemotherapy is associated with decreased postoperative breast satisfaction, but whether timing as neoadjuvant (NAC) versus adjuvant (AC) affects this outcome after breast conservation therapy (BCT) and mastectomy with immediate reconstruction (M-IR) is unclear. Methods: We retrospectively identified patients treated with chemotherapy and breast surgery (BCT and M-IR), from 1/2017-12/2019, who completed ≥ 1 BREAST-Q survey through 12/2020. Mean (standard deviation [SD]) Q-scores for satisfaction with breasts (SATBR) were compared between NAC versus AC groups in BCT and M-IR cohorts, respectively. Higher Q-scores on a 0-100 scale indicate superior satisfaction. A minimum 4-point difference was considered clinically important. Chemotherapy timing and significant covariates on univariate analyses were entered in multivariable linear regressions of 1- and 2-year SABTR. Results: 640 patients had BCT and 602 had M-IR; 210 (33%) BCT patients and 294 (49%) M-IR patients had NAC. Compared with M-IR, SATBR was higher after BCT in both NAC and AC groups, at all postoperative timepoints (Table). Following BCT, SABTR was highest in both NAC and AC groups at 6 months and returned to baseline in the NAC group by year 3. In the M-IR cohort, 331 (55%) patients had radiation and 120 (20%) had complications requiring re-operation or hospitalization. Compared with baseline, mean (SD) Q-scores were substantially lower at 6 months but improved to near baseline at 3 years in both NAC and AC groups. On multivariable analysis, radiation was associated with decreased SABTR at 1 year (Beta, -11; 95% CI, -17, -5.0; p<0.001) and 2 years (Beta, -12; 95% CI, -19, -5.5; p<0.001), as were complications at 1 year (Beta, -6.1; 95% CI, -12, -0.34; p=0.038) but not 2 years (Beta, -5.5; 95% CI, -12, 0.92; p=0.09). After multivariable adjustment, NAC was not significantly associated with 1- or 2-year SABTR after M-IR or BCT. Conclusions: SABTR was higher in BCT compared with M-IR cohorts, independent of chemotherapy timing. Following BCT, SABTR was lower in the NAC group at years 2-3 but remained at baseline or higher at all timepoints. In the M-IR cohort, both groups endorsed lower than baseline SABTR in years 0-2 but returned to near baseline at 3 years. Radiation and complications were independent predictors of decreased SABTR, but our findings suggest that patients who experience complications after M-IR can expect return to baseline breast satisfaction by 2 years.[Table: see text]