Prospective Multicenter Study Validate a Prediction Model for Surgery Uptake Among Women with Atypical Breast Lesions.

BACKGROUND: Diagnosis of atypical breast lesions (ABLs) leads to unnecessary surgery in 75-90% of women. We have previously developed a model including age, complete radiological target excision after biopsy, and focus size that predicts the probability of cancer at surgery. The present study aimed to validate this model in a prospective multicenter setting. - METHODS: Women with a recently diagnosed ABL on image-guided biopsy were recruited in 18 centers, before wire-guided localized excisional lumpectomy. Primary outcome was the negative predictive value (NPV) of the model. RESULTS: The NOMAT model could be used in 287 of the 300 patients included (195 with ADH). At surgery, 12 invasive (all grade 1), and 43 in situ carcinomas were identified (all ABL: 55/287, 19%; ADH only: 49/195, 25%). The area under the receiving operating characteristics curve of the model was 0.64 (95% CI 0.58-0.69) for all ABL, and 0.63 for ADH only (95% CI 0.56-0.70). For the pre-specified threshold of 20% predicted probability of cancer, NPV was 82% (77-87%) for all ABL, and 77% (95% CI 71-83%) for patients with ADH. At a 10% threshold, NPV was 89% (84-94%) for all ABL, and 85% (95% CI 78--92%) for the ADH. At this threshold, 58% of the whole ABL population (and 54% of ADH patients) could have avoided surgery with only 2 missed invasive cancers. CONCLUSION: The NOMAT model could be useful to avoid unnecessary surgery among women with ABL, including for patients with ADH. CLINICAL TRIAL REGISTRATION: NCT02523612.

The actual benefit of intraoperative radiation therapy using 50 kV x-rays in early breast cancer: A retrospective study of 676 patients.

This French study reports the 5-year results of partial-breast irradiation using intraoperative radiation therapy (IORT) with 50 kV x-rays, in select early breast cancer patients. We report a retrospective analysis of 676 consecutive early breast cancer patients treated between November 2011 and December 2015 by partial-breast irradiation using the INTRABEAM® system. Patients were highly selected based on the ASTRO and GEC-ESTRO criteria and underwent breast-conservative surgery and IORT, completed with additional whole-breast irradiation (WBI) when unexpected unfavorable prognostic factors were found at the final pathology report. Patients' outcomes relative to local and distant control, overall and breast cancer-specific survival, and toxicity are presented, as well as rates of additional WBI. Additional WBI was mandatory in one third of patients (31%), mainly due to lymph node involvement and extensive intraductal component. With a median follow-up time of 54 months, the 5-year local recurrence rate was 1.7% [95%CI: 0.9-3.3]; the median time to local recurrence was 23 months; ipsilateral breast recurrences mainly occurred in the same quadrant (7/11); in the restricted population, meeting all predefined criteria and treated with IORT alone (406 patients), the local recurrence rate was 1.5% [95%CI: 0.6-3.6]. Five-year distant tumor control was 98.6% [95%CI: 97.2-99.3], and the median time to distant recurrence was 22 months. Five-year overall survival was 96.5% [95%CI: 94.2-97.8], and 5-year breast cancer-specific survival was 98.9% [95%CI: 97.6-99.7]. In patients treated with IORT alone, there was no grade 3 toxicity, only four grade 3 (mainly fibrosis) affected patients treated with IORT and WBI. Grade 1-2 toxicity rates were 14% and 34.4% in patients treated with IORT alone and IORT plus WBI, respectively. Partial-breast irradiation using IORT by a 50 kV photon device is safe and well-tolerated in select patients with early breast cancer and is a valuable option in patients reluctant for adjuvant WBI.

Robotic Nipple-Sparing Mastectomy and Immediate Breast Reconstruction With Robotic Latissimus Dorsi Flap Harvest: Technique and Results.

Introduction. Only few cases of robotic latissimus dorsi flap reconstruction (RLDFR) have been reported in indication of reconstruction for breast cancer (BC). We report our experience of combined robotic nipple-sparing mastectomy (R-NSM) and RLDFR, and analyze technique, indications, and reproducibility. Methods. All patients with R-NSM and RLDFR from November 2016 to August 2, 2018, were analyzed, and technics have been described. Complication rate with Clavien-Dindo grading and postoperative hospitalization length (days) are reported. Results. Thirty-five R-NSM with RLDFR were performed in 22 cases for primitive BC and 13 for local recurrence. In 12 patients, another surgical procedure was performed during the same time (axillary lymph node dissection or contralateral breast surgery). R-NSM was realized through a short axillar incision, with inside-only installation for 12 patients (34.3%): 18 nonautologous and 17 autologous RLDFR associated with implant in 9 patients. In logistic regression, mastectomy weight >330 g was significantly associated with the use of implant (odds ratio [OR] = 17, P = .015), and significant factor of the time of anesthesia ≥380 minutes was 2 installations (OR = 10.4, P = .049). The median duration of hospitalization stay was 4 days. Complications rates were 51.4% (18/35; 9 grade-1, 2 grade-2, and 7 grade-3). In logistic regression, associated other surgical procedure was predictive of grade-3 complications (OR = 6.87, P = .053). Conclusion. We confirmed the reproducibility and safety of R-NSM and RLDFR with a decreased complication rate. NSM was performed in 42.8% of our patients after previous radiotherapy. We observed an increase of grade-3 complications when R-NSM and RLDFR was combined to another surgical procedure.

Adjuvant chemotherapy in lobular carcinoma of the breast: a clinicopathological score identifies high-risk patient with survival benefit.

BACKGROUND: Invasive lobular carcinomas (ILCs) represent approximately 10% of all breast cancers. Despite this high frequency, benefit of adjuvant chemotherapy (CT) is still unclear. METHODS: Our objective was to investigate the impact of CT on survival in ILC. Patients were retrospectively identified from a cohort of 23,319 patients who underwent primary surgery in 15 French centers between 1990 and 2014. Only ILC, hormone-positive, human epidermal growth factor 2 (HER2)-negative patients who received adjuvant endocrine therapy (ET) were included. End-points were disease-free survival (DFS) and overall survival (OS). A propensity score for receiving CT, aiming to compensate for baseline characteristics, was used. RESULTS: Of a total of 2318 patients with ILC, 1485 patients (64%) received ET alone and 823 (36%) received ET + CT. We observed a beneficial effect of addition of CT to ET on DFS and OS in multivariate Cox model (HR = 0.61, 95% confidence interval, CI [0.41-0.90]; p = 0.01 and 0.52, 95% CI [0.31-0.87]; p = 0.01, respectively). This effect was even more pronounced when propensity score matching was used. Regarding subgroup analysis, low-risk patients without CT did not have significant differences in DFS or OS compared to low-risk patients with CT. CONCLUSION: ILC patients could derive significant DFS and OS benefits from CT, especially for high-risk patients.

Isolated ipsilateral local recurrence of breast cancer: predictive factors and prognostic impact.

BACKGROUND: Tumour features associated with isolated invasive breast cancer (BC) ipsilateral local recurrence (ILR) after breast conservative treatment (BCT) and consequences on overall survival (OS) are still debated. Our objective was to investigate these points. METHODS: Patients were retrospectively identified from a cohort of patients who underwent BCT for invasive BC in 16 cancer centres. End-points were ILR rate and OS. The impact of ILR on OS was assessed by multivariate analysis (MVA) for all patients and according to endocrine receptors (ERs) and grade or tumour subtypes. RESULTS: Of 15,570 patients, ILR rate was 3.1%. Cumulative ILR rates differed according to ERs/grade (ERs+/Grade2: HR 1.42, p = 0.010; ERs+/Grade3: HR 1.41, p = 0.067; ERs-: HR 2.14, p < 0.0001), endocrine therapy (HR 2.05, p < 0.0001) and age < 40-years old (HR 2.28, p = 0.005) in MVA. When MVA was adjusted on tumour subtype, the latter was the only independent factor. OS-after-ILR was significantly different according to ILR-free intervals (HR 4.96 for ILR-free interval between 2 and 5-years and HR 9.00 when < 2-years, in comparison with ≥ 5-years). CONCLUSION: ERs/Grade status, lack of endocrine therapy and tumour subtypes predict isolated ILR risk in patients treated with BCT. Short ILR-free-intervals represent a strong pejorative factor for OS. These results may help selecting initial treatment as well as tailoring ILR systemic chemotherapy.

Lymph node positivity in different early breast carcinoma phenotypes: a predictive model.

BACKGROUND: A strong correlation between breast cancer (BC) molecular subtypes and axillary status has been shown. It would be useful to predict the probability of lymph node (LN) positivity. OBJECTIVE: To develop the performance of multivariable models to predict LN metastases, including nomograms derived from logistic regression with clinical, pathologic variables provided by tumor surgical results or only by biopsy. METHODS: A retrospective cohort was randomly divided into two separate patient sets: a training set and a validation set. In the training set, we used multivariable logistic regression techniques to build different predictive nomograms for the risk of developing LN metastases. The discrimination ability and calibration accuracy of the resulting nomograms were evaluated on the training and validation set. RESULTS: Consecutive sample of 12,572 early BC patients with sentinel node biopsies and no neoadjuvant therapy. In our predictive macro metastases LN model, the areas under curve (AUC) values were 0.780 and 0.717 respectively for pathologic and pre-operative model, with a good calibration, and results with validation data set were similar: AUC respectively of 0.796 and 0.725. Among the list of candidate's regression variables, on the training set we identified age, tumor size, LVI, and molecular subtype as statistically significant factors for predicting the risk of LN metastases. CONCLUSIONS: Several nomograms were reported to predict risk of SLN involvement and NSN involvement. We propose a new calculation model to assess this risk of positive LN with similar performance which could be useful to choose management strategies, to avoid axillary LN staging or to propose ALND for patients with high level probability of major axillary LN involvement but also to propose immediate breast reconstruction when post mastectomy radiotherapy is not required for patients without LN macro metastasis.

Skin sparing mastectomy and robotic latissimus dorsi-flap reconstruction through a single incision.

BACKGROUND: Robotic latissimus dorsi-flap reconstruction (RLDFR) after skin-sparing mastectomy (SSM) for breast cancer (BC) has been performed through a single nipple incision. We report results of SSM with RLDFR, mainly with analysis of feasibility, morbidity, indications, and technique standardization. METHODS: We determined characteristics of patients, previous treatment of BC, and type of reconstruction. Surgical technique, duration of surgery, and complication rate were reported according to three successive periods: P1-3. RESULTS: Forty RLDFR, with breast implant for 16 patients, with previous breast radiotherapy in 30% had been performed. In logistic regression, factors significantly associated with duration of surgery ≥ 300 min were P2 (OR 0.024, p = 0.004) and P3 (OR 0.012, p = 0.004) versus P1. The median mastectomy weight was 330 g and 460 g for BMI < and ≥ 23.5 (p = 0.025). Length of hospitalization was 4 days. Total complication rate was 20% (8/40): seven breast complications (four re-operations) and one RLDF complication with re-operation. Periods were significantly predictive of complications (p = 0.045). CONCLUSION: SSM with RLDFR is feasible, safe, and reproducible. We reported a decrease of duration of surgery, length of post-operative hospitalization, and complication rate.

Overview of the pathological results and treatment characteristics in the first 1000 patients randomized in the SERC trial: axillary dissection versus no axillary dissection in patients with involved sentinel node.

BACKGROUND: Three randomized trials have concluded at non inferiority of omission of complementary axillary lymph node dissection (cALND) for patients with involved sentinel node (SN). However, we can outline strong limitations of these trials to validate this attitude with a high scientific level. We designed the SERC randomized trial ( ClinicalTrials.gov , number NCT01717131) to compare outcomes in patients with SN involvement treated with ALND or no further axillary treatment. The aim of this study was to analyze results of the first 1000 patients included. METHODS: SERC trial is a multicenter non-inferiority phase 3 trial. Multivariate logistic regression analysis was used to identify independent factors associated with adjuvant chemotherapy administration and non-sentinel node (NSN) involvement. RESULTS: Of the 963 patients included in the analysis set, 478 were randomized to receive cALND and 485 SLNB alone. All patient demographics and tumor characteristics were balanced between the two arms. SN ITC was present in 6.3% patients (57/903), micro metastases in 33.0% (298), macro metastases in 60.7% (548) and 289 (34.2%) were non eligible to Z0011 trial criteria. Whole breast or chest wall irradiation was delivered in 95.9% (896/934) of patients, adjuvant chemotherapy in 69.5% (644/926), endocrine therapy in 89.6% (673/751) and the proportions were similar in the two arms. The overall rate of positive NSN was 19% (84/442) for patients with cALND. Crude rates of positive NSN according to SN status were 4.5% for ITC (1/22), 9.5% for micro metastases (13/137), 23.9% for macro metastases (61/255) and were respectively 29.36% (64/218), 9.33% (7/75) and 7.94% (10/126) when chemotherapy was administered after cALND, before cALND and for patients without chemotherapy. CONCLUSION: The main objective of SERC trial is to demonstrate non inferiority of cALND omission. A strong interaction between timing of cALND and chemotherapy with positive NSN rate was observed. TRIAL REGISTRATION: This study is registered with ClinicalTrials.gov , number NCT01717131 October 19, 2012.

Contribution of intraoperative radiotherapy (IORT) for therapeutic de-escalation in early breast cancer: Report of a single institution's experience.

The spread of systematic screening and the emergence of oncoplastic techniques allow more breast conservative treatment associating lumpectomy and external beam radiation therapy. In order to furthermore facilitate the patient's treatment, intraoperative radiation therapy (IORT) has been developed. The oncological safety of this technique has been studied, and is considered acceptable. Many questions remain unsolved in regard of the toxicity of this procedure as well as the patient's selection criteria. In this study, we present the first results and complications rate of patients treated by IORT in a single French institution. Between 2012 and 2015, all patients with breast cancer treated in a one-step procedure associating lumpectomy and IORT were retrospectively included in a monocentric cohort. Acute and long-term toxicities were evaluated using CTCAE v4.0 classification. 280 breast cancers were treated using IORT procedure. Additional external beam radiation therapy was requested for 45.7% patients. The acute complications rate was 14.6%, with 5 surgical revisions needed (1.78%). With a median follow up of 911 days, the long-term grade-3 toxicity rate was 1.1%. The only risk factor for local fibrosis was external beam radiation therapy (EBRT) (OR = 1.99; IC95 [1.05-3.81], P = 0.036). Three patients (1.07%) were diagnosed with local recurrence. The results from this cohort confirm the low complication and recurrence rate of IORT procedure. A good selection of patients is necessary in order to lower the EBRT rate and allow therapeutic de-escalation. The classification of tumors into IHC subsets seems a good selection gate. Intraoperative radiation therapy appears to have a low toxicity rate with an acceptable local recurrence risk, and should therefore be considered as an option in the treatment of early breast cancer.

Benefit of adjuvant chemotherapy with or without trastuzumab in pT1ab node-negative human epidermal growth factor receptor 2-positive breast carcinomas: results of a national multi-institutional study.

PURPOSE: Benefit of adjuvant trastuzumab-based chemotherapy for node-positive and/or >1 cm human epidermal growth factor receptor 2-positive (HER2+) breast carcinomas has been clearly demonstrated in randomized clinical trials. Yet, evidence that adjuvant chemotherapy with or without trastuzumab is effective in pT1abN0 HER2+ tumors is still limited. The primary objective of this study was to investigate the impact of adjuvant chemotherapy ± trastuzumab on outcome in this subpopulation. PATIENTS AND METHODS: A total of 356 cases of pT1abN0M0 HER2 + breast cancers were retrospectively identified from a large cohort of 22,334 patients, including 1248 HER2+ patients who underwent primary surgery at 17 French centers, between December 1994 and January 2014. The primary end point was disease-free survival (DFS). A multivariate Cox model was built, including adjuvant chemotherapy, tumor size, hormone receptor status, and Scarff Bloom Richardson (SBR) grade. RESULTS: A total of 138 cases (39%) were treated with trastuzumab-based chemotherapy, 29 (8%) with chemotherapy alone, and 189 (53%) received neither trastuzumab nor chemotherapy. Adjuvant chemotherapy ± trastuzumab was associated with a significant DFS benefit (3-year 99 vs. 90%, and 5-year 96 vs. 84%, Hazard ratio, HR 0.26 [0.10-0.67]; p = 0.003, logrank test) which was maintained in multivariate analysis (HR 0.19 [0.07-0.52]; p = 0.001). Metastasis-free survival was also increased (HR 0.25 [0.07-0.86]; p = 0.018, logrank test) at 3-year (99 vs. 95%) and 5-year (98 vs. 89%) censoring. Exploratory subgroup analysis found DFS benefit to be significant in hormone receptor-negative, hormone receptor-positive, and pT1b tumors, but not in pT1a tumors. CONCLUSIONS: Adjuvant chemotherapy ± trastuzumab is associated with a significantly reduced risk of recurrence in subcentimeter node-negative HER2+ breast cancers. Most of the benefit may be driven by pT1b tumors.

A Prospective Study on Skin-Sparing Mastectomy for Immediate Breast Reconstruction with Latissimus Dorsi Flap After Neoadjuvant Chemotherapy and Radiotherapy in Invasive Breast Carcinoma.

BACKGROUND: Skin-sparing mastectomy (SSM) with immediate breast reconstruction (IBR) is increasingly used in invasive breast cancer. However, adjuvant chemotherapy (CT) and radiotherapy (RT) can increase the rate of local complications. OBJECTIVE: The aim of this study was to assess the morbidity of SSM-IBR after neoadjuvant CT and RT. METHODS: A French prospective pilot study of women aged 18-75 years with invasive breast cancer requiring mastectomy after CT and RT. Reconstruction was performed using autologous latissimus dorsi flap with or without prosthesis. The primary endpoint was the skin necrosis rate within 6 months, while secondary endpoints included pathological complete response rate (pCR) and global morbidity. RESULTS: Among 94 patients included in this study, 83 were analyzed (mean age 45.2 ± 9.5 years, T1 23.6 %, T2 55.6 %, T3 18.1 %). All but one patient received anthracyclines and taxanes, and all patients received RT (49.3 ± 5.2 Gy) before SSM-IBR. Prostheses were used for IBR in 32 patients (mean volume 256 ± 73 mm(3)). Five patients had necrosis (≤2 cm(2), 2-10 cm(2) and >10 cm(2), in three, one, and one cases, respectively), and they all recovered without revision surgery. Among 50 patients who underwent upfront mastectomy, 36 % achieved pCR. CONCLUSIONS: SSM-IBR performed after CT and RT is safe, with an acceptable local morbidity rate. Long-term data are needed to evaluate recurrence rates.

Exclusive intraoperative radiotherapy for invasive breast cancer in elderly patients (>70 years): proportion of eligible patients and local recurrence-free survival.

BACKGROUND: To estimate the proportion of elderly patients (>70 years) with breast cancer eligible for an Exclusive IntraOperative RadioTherapy (E-IORT) and to evaluate their local recurrence-free survival rate. METHODS: This retrospective study examining two cohorts focuses on patients over 70 years old: a multi-centric cohort of 1411 elderly patients and a mono-centric cohort of 592 elderly patients. All patients underwent conservative surgery followed by external radiotherapy for T0-T3 N0-N1 invasive breast cancer, between 1980 and 2008. RESULTS: Within each cohort two groups were identified according to the inclusion criteria of the RIOP trial (R group) and TARGIT E study (T group). Each group was divided into two sub-groups, patients eligible (E) or non-eligible (nE) for IORT. The population of patients that were eligible in the TARGIT E study but not in the RIOP trial were also studied in both cohorts. The proportion of patients eligible for IORT was calculated, according to the eligibility criteria of each study. A comparison of the 5-year local or locoregional recurrence-free survival rate between eligible vs non-eligible patients was made. In both cohorts, the proportion of patients eligible according to the RIOP trial's eligibility criteria was 35.4 and 19.3%, and according to the TARGIT E study criteria was 60.9 and 45.3%. The 5-year locoregional recurrence-free survival rate was not significantly different between RE and RnE groups, TE and TnE groups. In both cohorts RE and (TE-RE) groups were not significantly different. CONCLUSIONS: Our results encourage further necessary studies to define and to extend the eligibility criteria for per operative exclusive radiotherapy.

Eligibility criteria for intraoperative radiotherapy for breast cancer: study employing 12,025 patients treated in two cohorts.

BACKGROUND: We wished to estimate the proportion of patients with breast cancer eligible for an exclusive targeted intraoperative radiotherapy (TARGIT) and to evaluate their survival without local recurrence. METHODS: We undertook a retrospective study examining two cohorts. The first cohort was multicentric (G3S) and contained 7580 patients. The second cohort was monocentric (cohort 2) comprising 4445 patients. All patients underwent conservative surgery followed by external radiotherapy for invasive breast cancer (T0-T3, N0-N1) between 1980 and 2005. Within each cohort, two groups were isolated according to the inclusion criteria of the TARGIT A study (T group) and RIOP trial (R group).In the multicentric cohort (G3S) eligible patients for TARGIT A and RIOP trials were T1E and R1E subgroups, respectively. In cohort number 2, the corresponding subgroups were T2E and R2E. Similarly, non-eligible patients were T1nE, R1nE and T2nE, and R2nE.The eligible groups in the TARGIT A study that were not eligible in the RIOP trial (TE-RE) were also studied. The proportion of patients eligible for TARGIT was calculated according to the criteria of each study. A comparison was made of the 5-year survival without local or locoregional recurrence between the TE versus TnE, RE versus RnE, and RE versus (TE-RE) groups. RESULTS: In G3S and cohort 2, the proportion of patients eligible for TARGIT was, respectively, 53.2% and 33.9% according the criteria of the TARGIT A study, and 21% and 8% according the criteria of the RIOP trial. Survival without five-year locoregional recurrence was significantly different between T1E and T1nE groups (97.6% versus 97% [log rank=0.009]), R1E and R1nE groups (98% versus 97.1% [log rank=0.011]), T2E and T2nE groups (96.6% versus 93.1% [log rank<0. 0001]) and R2E and R2nE groups (98.6% versus 94% [log rank=0.001]). In both cohorts, no significant difference was found between RE and (TE-RE) groups. CONCLUSIONS: Almost 50% of T0-2 N0 patients could be eligible for TARGIT.

Omission of Completion Axillary Lymph Node Dissection for Patients with Breast Cancer Treated by Upfront Mastectomy and Sentinel Node Isolated Tumor Cells or Micrometastases.

Omission of completion axillary lymph node dissection (cALND) in patients undergoing mastectomy with sentinel node (SN) isolated tumor cells (ITC) or micrometastases is debated due to potential under-treatment, with non-sentinel node (NSN) involvement detected in 7% to 18% of patients. This study evaluated the survival impact of cALND omission in a cohort of breast cancer (BC) patients treated by mastectomy with SN ITC or micrometastases. Among 554 early BC patients (391 pN1mi, 163 ITC), the NSN involvement rate was 13.2% (49/371). With a median follow-up of 66.46 months, multivariate analysis revealed significant associations between cALND omission and overall survival (OS, HR: 2.583, p = 0.043), disease-free survival (DFS, HR: 2.538, p = 0.008), and metastasis-free survival (MFS, HR: 2.756, p = 0.014). For Her2-positive or triple-negative patients, DFS was significantly affected by cALND omission (HR: 38.451, p = 0.030). In ER-positive Her2-negative BC, DFS, OS, recurrence-free survival (RFS), and MFS were significantly associated with cALND omission (DFS HR: 2.358, p = 0.043; OS HR: 3.317; RFS HR: 2.538; MFS HR: 2.756). For 161 patients aged ≤50 years with ER-positive/Her2-negative cancer, OS and breast cancer-specific survival (BCSS) were notably impacted by cALND omission (OS HR: 103.47, p = 0.004; BCSS HR: 50.874, p = 0.035). These findings suggest a potential negative prognostic impact of cALND omission in patients with SN micrometastases or ITC. Further randomized trials are needed.

Neoadjuvant chemotherapy for breast cancer: Pathologic response rates but not tumor size, has an independent prognostic impact on survival.

AIM: We investigated the pathologic complete response rates (pCR) and survival outcomes of early breast cancer patients who underwent neoadjuvant chemotherapy (NAC) over 14 years at a French comprehensive cancer center and reported pCR and survival outcomes by tumor subtypes and size. METHODS: From January 2005 to December 2018, 1150 patients receiving NAC were identified. Correlations between cT stage, breast tumor response, axillary lymph node response, pCR, surgery, and outcomes were assessed. pCR was defined as (ypT0/ypTis) and (ypN0/pN0sn). RESULTS: A pCR was reached in 31.7% (365/1150) of patients and was strongly associated with tumor subtypes, but not with tumor size (pretreatment cT category). Luminal-B Her2-negative and triple-negative (TN) subtypes, cN1 status, older age, and no-pCR had an independent negative prognostic value. Overall survival (OS), relapse-free survival (RFS), and metastasis-free survival (MFS) were not significantly different for cT0-1 compared to cT2 stages. In Cox-model adjusted on in-breast pCR and pN status, ypN1 had a strong negative impact (OS, RFS, and MFS: HR = 3.153, 4.677, and 6.133, respectively), higher than no in-breast pCR (HR = 2.369, 2.252, and 2.323). A negative impact of no pCR on OS was observed for cN0 patients and TN tumors (HR = 4.972) or HER2-positive tumors (HR = 11.706), as well as in Luminal-B Her2-negative tumors on MFS (HR = 2.223) and for Luminal-A on RFS (HR = 4.465) and MFS (HR = 4.185). CONCLUSION: Achievement of pCR, but not tumor size (pretreatment cT category), has an independent prognostic impact on survival. These results suggest potential NAC benefits in patients with small tumors (<2 cm), even in absence of clinically suspicious lymph nodes. Residual lymph node disease after NAC is the most powerful adverse prognostic factor.

Postoperative Outcomes of Pre-Pectoral Versus Sub-Pectoral Implant Immediate Breast Reconstruction.

INTRODUCTION: Immediate breast reconstruction (IBR) techniques are rapidly evolving. We compared the results from a single-center implant IBR cohort between subpectoral and prepectoral implants with and without a mesh. METHODS: We analyzed all complications and grade 2-3 complications, the implant loss rate, the surgery time, the length of stay (LOS), patient satisfaction, the interval time to adjuvant therapy and cost, with a comparison between subpectoral and prepectoral implant IBR. RESULTS: Subpectoral implant IBR was carried out in 529 mastectomies (62.0%) and prepectoral in 324, with a significant increase in prepectoral placement in recent years. Mesh was used in 176 prepectoral placements (54.3%). Any grade of complication was reported in 147 mastectomies (17.2%), with a significantly higher rate for prepectoral implant IBR (p = 0.036). Regression analysis showed that prepectoral implant was not significantly associated with any grade of complication or with grade 2-3 complications. Prepectoral implant IBR was associated with a significantly shorter operative time and lower LOS. Grade 2-3 complications were significantly associated with lower satisfaction. Higher costs were significantly associated with the subpectoral placement and mesh. A complication rate predictive score identified five groups with a significant increase in grade 2-3 complications. CONCLUSIONS: Prepectoral-M-IBR increased over time with no difference in complication rates compared to subpectoral-M-IBR. Prepectoral implant placement can be considered a safe technique.

Eligibility for Adjuvant Cyclin-Dependent Kinase 4/6 Inhibitors in Endocrine Receptor-Positive and HER2-Negative Early Breast Cancer by Age and Type of Surgery.

Background: Despite early diagnosis, approximately 20% of patients with ER-positive and HER2-negative breast cancer (BC) will experience disease recurrence. Improved survival has been reported with adjuvant treatment combining cyclin-dependent kinase 4/6 inhibitors with endocrine therapy, in high-risk patients with ER-positive and HER2-negative BC, regardless of age. Older patients have higher rates of ER-positive/HER2-negative BC than younger patients. Methods: In this real-world data analysis, MonarchE and NataLEE high-risk patients accounted for 9.5% and 33% of patients undergoing upfront surgery, respectively. Significantly higher eligibility rates were observed in patients who underwent a mastectomy, >70 years and ≤40 years for adjuvant abemaciclib and ribociclib, and in patients >80 years for ribociclib. Results: Eligibility rates in patients ≤40 years and >80 years who underwent mastectomy were 27.8% and 24.7% for abemaciclib, respectively, and 56.6% and 65.2% for ribociclib, respectively. A higher discontinuation rate for abemaciclib was reported in patients aged ≥65 years and it can be assumed that discontinuation rates may increase in even older patients. Conclusions: If the results of the NataLEE trial translate into clinical practice, the number of patients potentially eligible for adjuvant CDK4/6 inhibitors may increase, especially in the elderly population.

Does Breast Surgery Type Alter Incidental Axillary Irradiation? A Dosimetric Analysis of the "Sentinel Envahi et Randomisation du Curage" SERC Trial.

BACKGROUND: An incidental axillary dose of adjuvant radiotherapy using tangential beams is usually given after breast-conserving surgery for breast cancer. The goal of this sub-study was to evaluate this incidental dose in the setting of post-mastectomy radiotherapy (PMRT) according to two different radiotherapy techniques. METHODS: Patients participating in a randomized SERC trial who received PMRT in a single center were included. We collected the incidental axillary dose delivered to the Berg level 1 using different dosimetric parameters and compared two techniques using Student's t-test: three-dimensional conformal radiotherapy (3D-CRT) and volumetric arc therapy (VMAT). RESULTS: We analyzed radiotherapy plans from 52 patients who received PMRT from 2012 to 2021. The mean dose delivered to the Berg level 1 was 37.2 Gy. It was significantly higher with VMAT than with 3D-CRT-43.6 Gy (SD = 3.1 Gy) versus 34.8 Gy (SD = 8.6 Gy) p < 0.001. Eighty-four percent of the Berg level 1 was covered by 40 Gy isodose in the VMAT group versus 55.5% in the 3D-CRT group p < 0.001. CONCLUSIONS: On the Berg level 1, PMRT gives a dose at least equivalent to the one given by post-breast-conserving surgery radiotherapy, making it possible to limit completion axillary lymph node dissections in select pN1a patients treated with a mastectomy. Modern radiotherapy techniques like VMAT tend to increase this incidental dose.

Early breast cancer in women aged 35 years or younger: A large national multicenter French population-based case control-matched analysis.

BACKGROUND: There is a scarcity of data exploring early breast cancer (eBC) in very young patients. We assessed shared and intrinsic prognostic factors in a large cohort of patients aged ≤35, compared to a control group aged 36 to 50. METHODS: Patients ≤50 were retrospectively identified from a multicentric cohort of 23,134 eBC patients who underwent primary surgery between 1990 and 2014. Multivariate Cox analyses for DFS and OS were built. To assess the independent impact of age, 1 to 3 case-control analysis was performed by matching ≤35 and 36-50 years patients. RESULTS: Of 6481 patients, 556 were aged ≤35, and 5925 from 36 to 50. Age ≤35 was associated with larger tumors, higher grade, ER-negativity, macroscopic lymph node involvement (pN + macro), lymphovascular invasion (LVI), mastectomy, and chemotherapy (CT) use. In multivariate analysis, age ≤35 was associated with worse DFS [HR 1.56, 95% CI 1.32-1.84; p < 0.001], and OS [HR 1.29, 95% CI 1.03-1.60; p = 0.025], as were high grade, large tumor, LVI, pN + macro, ER-negativity, period of diagnostic, and absence of ET or CT (for DFS). Adverse prognostic impact of age ≤35 was maintained in the case control-matched analysis for DFS [HR 1.56, 95%CI 1.28-1.91, p < 0.001], and OS [HR 1.33, 95%CI 1.02-1.73, p = 0.032]. When only considering patients ≤35, ER, tumor size, nodal status, and LVI were independently associated with survival in this subgroup. CONCLUSIONS: Age ≤35 is associated with less favorable presentation and more aggressive treatment strategies. Our results support the poor prognosis value of young age, which independently persisted when adjusting for other prognostic factors and treatments.

Negative Survival Impact of Occult Lymph Node Involvement in Small HER2-Positive Early Breast Cancer Treated by Up-Front Surgery.

(1) Background: The independent negative prognostic value of isolated tumor cells or micro-metastases in axillary lymph nodes has been established in triple-negative breast cancers (BC). However, the prognostic significance of pN0(i+) or pN1mi in HER2-positive BCs treated by primary surgery remains unexplored. Therefore, our objective was to investigate the impact of pN0(i+) or pN1mi in HER2-positive BC patients undergoing up-front surgery on their outcomes. (2) Methods: We retrospectively analyzed 23,650 patients treated in 13 French cancer centers from 1991 to 2013. pN status was categorized as pN0, pN0(i+), pN1mi, and pNmacro. The effect of pN0(i+) or pN1mi on outcomes was investigated both in the entire cohort of patients and in pT1a-b tumors. (3) Results: Of 1771 HER2-positive BC patients included, pN status distributed as follows: 1047 pN0 (59.1%), 60 pN0(i+) (3.4%), 118 pN1mi (6.7%), and 546 pN1 macro-metastases (30.8%). pN status was significantly associated with sentinel lymph node biopsy, axillary lymph node dissection, age, ER status, tumor grade, and size, lymphovascular invasion, adjuvant systemic therapy (ACt), and radiation therapy. With 61 months median follow-up (mean 63.2; CI 95% 61.5-64.9), only pN1 with macro-metastases was independently associated with a negative impact on overall, disease-free, recurrence-free, and metastasis-free survivals in multivariate analysis. In the pT1a-b subgroup including 474 patients, RFS was significantly decreased in multivariate analysis for pT1b BC without ACt (HR 2.365, 1.04-5.36, p = 0.039) and for pN0(i+)/pN1mi patients (HR 2.518, 1.03-6.14, p = 0.042). (4) Conclusions: Survival outcomes were not adversely affected by pN0(i+) and pN1mi in patients with HER2-positive BC. However, in the case of pT1a-b HER2-positive BC, a negative impact on RFS was observed specifically for patients with pN0(i+) and pN1mi diseases, particularly among those with pT1b tumors without ACt. Our findings highlight the importance of considering the pN0(i+) and pN1mi status in the decision-making process when discussing trastuzumab-based ACt for these patients.