Patterns of Recurrence and Predictors of Survival in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy, Surgery, and Radiation.

Neoadjuvant chemotherapy (NAC) is standard of care for locally advanced breast cancer. There is wide variation in radiation therapy (RT) practice and limited data describing locoregional relapse (LRR) after NAC. We hypothesized a low LRR risk with modern NAC, surgery, and RT and aimed to elucidate patterns of LRR and predictors of disease-free survival (DFS) and overall survival (OS) in these patients. Data from 416 patients with stage II/III breast cancer treated between 2008 and 2015 with NAC, surgery, and adjuvant RT were reviewed retrospectively. DFS and OS rates were calculated using the Kaplan-Meier method. The LRR rate was estimated using the cumulative incidence function, treating death as a competing risk. Multivariable survival analysis was performed using Cox regression. Median follow-up was 4.7 years. Most patients had cT2/3 (74%) cN1 (61%) disease and underwent mastectomy (75%) and axillary dissection (84%). Pathologic complete response (pCR) was achieved in 22% of patients. There were 27 LRRs (including 4 isolated LRRs) and 89 distant failures. Two patients developed LRR 2 months after surgery, before adjuvant RT. LRR could be mapped in 23 patients: most (20) recurred within the RT field; 1 in- and out-of-field; and 2 out-of-field. Five-year LRR, DFS, and OS were 6.4%, 77%, and 90%, respectively. On multivariable analysis, triple-negative subtype (hazard ratio [HR] 2.82; 95% confidence interval [CI], 1.78-4.47; P < .001), stage III disease (HR 1.72; 95% CI, 1.11-2.69; P = .016), and non-pCR (HR 4.76; 95% CI 2.13-10.0; P < .001) were associated with poor DFS and OS (HR 4.13 [95% CI, 2.21-7.72; P < .001]; HR 1.94 [95% CI, 1.001-3.75; P = .049]; and HR 2.38 [95% CI, 0.98-5.88; P = .055], respectively). Patients with breast cancer treated with modern NAC, surgery, and RT have a low 5-year LRR risk, with the majority occurring in-field. Triple-negative subtype, stage III disease, and non-pCR were associated with inferior DFS and OS.

Keilty D ，Nezafat Namini S ，Swain M ，Maganti M ，Cil TD ，McCready DR ，Cescon DW ，Amir E ，Fleming R ，Mulligan AM ，Fyles A ，Croke JM ，Liu FF ，Levin W ，Koch CA ，Han K ... -  《-》

Impact of Radiation on Locoregional Control in Women with Node-Positive Breast Cancer Treated with Neoadjuvant Chemotherapy and Axillary Lymph Node Dissection: Results from ACOSOG Z1071 Clinical Trial.

Use of adjuvant radiation therapy (RT) after neoadjuvant chemotherapy (NAC) in node-positive breast cancer (BC) is highly variable. In ACOSOG Z1071, RT after NAC was used at the discretion of treating physicians. Herein, we report the impact of RT and pathologic response on locoregional recurrence (LRR) after NAC. ACOSOG Z1071 enrolled women with cT0-4N1-2 BC treated with NAC from 2009 to 2011. Patients underwent sentinel node surgery and completion axillary lymph node dissection. The RT was at the discretion of the treating physicians. Patient outcomes were analyzed as a function of clinical-pathologic factors and use of RT. Of 701 eligible patients, mastectomy was performed in 423 (59.6%) and breast-conserving surgery in 277 (40.4%). After NAC, residual disease was observed in 506 (72.2%), and 195 (27.8%) had a pathologic complete response. Of the patients, 591 (85.3%) received adjuvant RT and 102 (14.7%) did not. Median follow-up was 5.9 years. Forty-three patients (6.1%) experienced LRR, 145 (20.7%) experienced distant metastasis, and 142 (20.4%) died. Patients with pathologic complete response had the best LRR-relapse-free survival (hazard ratio [HR], 0.32; 95% confidence interval, 0.12-0.81; P = .016), distant metastasis-free survival (HR, 0.31; 95% CI, 0.19-0.52; P < .0001), BC-specific survival (HR, 0.34; 95% CI, 0.19-0.59; P = .0001) and overall survival (HR, 0.39; 95% CI, 0.240-0.63; P = .001) compared to patients with residual disease after NAC. Patients with triple-negative BC had a higher LRR rate compared to those with hormone receptor-positive BC (HR, 5.91; 95% CI, 2.80-12.49). There was a trend toward lower LRR with the use of postmastectomy and regional nodal RT, but there was no impact on overall, disease-free, or BC-specific survival. In the ACOSOG Z1071 trial, in which the use of RT after NAC was at the discretion of the treating physicians, RT was associated with a trend toward decreased LRR. There was no association of RT with overall survival, BC-specific survival, or Disease Specific Survival. Triple-negative BC was associated with higher locoregional relapse rates.

Haffty BG ，McCall LM ，Ballman KV ，Buchholz TA ，Hunt KK ，Boughey JC ... -  《-》

The role of postmastectomy radiation therapy after neoadjuvant chemotherapy in clinical stage II-III breast cancer patients with pN0: a multicenter, retrospective study (KROG 12-05).

The purpose of this study was to investigate the role of postmastectomy radiation therapy (PMRT) after neoadjuvant chemotherapy (NAC) in clinical stage II-III breast cancer patients with pN0. We retrospectively identified 417 clinical stage II-III breast cancer patients who achieved an ypN0 at surgery after receiving NAC between 1998 and 2009. Of these, 151 patients underwent mastectomy after NAC. The effect of PMRT on disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), and overall survival (OS) was evaluated by multivariate analysis including known prognostic factors using the Kaplan-Meier method and compared using the log-rank test and Cox proportional regression analysis. Of the 151 patients who underwent mastectomy, 105 (69.5%) received PMRT and 46 patients (30.5%) did not. At a median follow-up of 59 months, 5 patients (3.3%) developed LRR (8 sites of recurrence) and 14 patients (9.3%) developed distant metastasis. The 5-year DFS, LRRFS, and OS rates were 91.2, 98.1, and 93.3% with PMRT and 83.0%, 92.3%, and 89.9% without PMRT, respectively (all P values not significant). By univariate analysis, only age (≤40 vs >40 years) was significantly associated with decreased DFS (P=.027). By multivariate analysis, age (≤40 vs >40 years) and pathologic T stage (0-is vs 1 vs 2-4) were significant prognostic factors affecting DFS (hazard ratio [HR] 0.353, 95% confidence interval [CI] 0.135-0.928, P=.035; HR 2.223, 95% CI 1.074-4.604, P=.031, respectively). PMRT showed no correlation with a difference in DFS, LRRFS, or OS by multivariate analysis. PMRT might not be necessary for pN0 patients after NAC, regardless of clinical stage. Prospective randomized clinical trial data are needed to assess whether PMRT can be safely omitted in pN0 patients after NAC and mastectomy for clinical stage II-III breast cancer.

Shim SJ ，Park W ，Huh SJ ，Choi DH ，Shin KH ，Lee NK ，Suh CO ，Keum KC ，Kim YB ，Ahn SD ，Kim SS ，Ha SW ，Chie EK ，Kim K ，Shin HS ，Kim JH ，Lee HS ... -  《-》

The Effect of Molecular Subtype and Residual Disease on Locoregional Recurrence in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy and Postmastectomy Radiation.

Yang TJ ，Morrow M ，Modi S ，Zhang Z ，Krause K ，Siu C ，McCormick B ，Powell SN ，Ho AY ... -  《-》

[The role of postmastectomy radiotherapy in clinical T1-3N1M0 breast cancer patients with pathological negative lymph nodes after neoadjuvant chemotherapy and mastectomy].

Rong QL ，Wang SL ，Tang Y ，Jin J ，Song YW ，Wang WH ，Liu YP ，Fang H ，Ren H ，Liu XF ，Yu ZH ，Li YX ... -  《-》