MRI-guided optimisation of neoadjuvant chemotherapy duration in stage II-III HER2-positive breast cancer (TRAIN-3): a multicentre, single-arm, phase 2 study

BACKGROUND

Patients with stage II-III HER2-positive breast cancer have good outcomes with the combination of neoadjuvant chemotherapy and HER2-targeted agents. Although increasing the number of chemotherapy cycles improves pathological complete response rates, early complete responses are common. We investigated whether the duration of chemotherapy could be tailored on the basis of radiological response.

METHODS

TRAIN-3 is a single-arm, phase 2 study in 43 hospitals in the Netherlands. Patients with stage II-III HER2-positive breast cancer aged 18 years or older and a WHO performance status of 0 or 1 were enrolled. Patients received neoadjuvant chemotherapy consisting of paclitaxel (80 mg/m2 of body surface area on day 1 and 8 of each 21 day cycle), trastuzumab (loading dose on day 1 of cycle 1 of 8 mg/kg bodyweight, and then 6 mg/kg on day 1 on all subsequent cycles), and carboplatin (area under the concentration time curve 6 mg/mL per min on day 1 of each 3 week cycle) and pertuzumab (loading dose on day 1 of cycle 1 of 840 mg, and then 420 mg on day 1 of each subsequent cycle), all given intravenously. The response was monitored by breast MRI every three cycles and lymph node biopsy. Patients underwent surgery when a complete radiological response was observed or after a maximum of nine cycles of treatment. The primary endpoint was event-free survival at 3 years; however, follow-up for the primary endpoint is ongoing. Here, we present the radiological and pathological response rates (secondary endpoints) of all patients who underwent surgery and the toxicity data for all patients who received at least one cycle of treatment. Analyses were done in hormone receptor-positive and hormone receptor-negative patients separately. This trial is registered with ClinicalTrials.gov, number NCT03820063, recruitment is closed, and the follow-up for the primary endpoint is ongoing.

FINDINGS

Between April 1, 2019, and May 12, 2021, 235 patients with hormone receptor-negative cancer and 232 with hormone receptor-positive cancer were enrolled. Median follow-up was 26·4 months (IQR 22·9-32·9) for patients who were hormone receptor-negative and 31·6 months (25·6-35·7) for patients who were hormone receptor-positive. Overall, the median age was 51 years (IQR 43-59). In 233 patients with hormone receptor-negative tumours, radiological complete response was seen in 84 (36%; 95% CI 30-43) patients after one to three cycles, 140 (60%; 53-66) patients after one to six cycles, and 169 (73%; 66-78) patients after one to nine cycles. In 232 patients with hormone receptor-positive tumours, radiological complete response was seen in 68 (29%; 24-36) patients after one to three cycles, 118 (51%; 44-57) patients after one to six cycles, and 138 (59%; 53-66) patients after one to nine cycles. Among patients with a radiological complete response after one to nine cycles, a pathological complete response was seen in 147 (87%; 95% CI 81-92) of 169 patients with hormone receptor-negative tumours and was seen in 73 (53%; 44-61) of 138 patients with hormone receptor-positive tumours. The most common grade 3-4 adverse events were neutropenia (175 [37%] of 467), anaemia (75 [16%]), and diarrhoea (57 [12%]). No treatment-related deaths were reported.

INTERPRETATION

In our study, a third of patients with stage II-III hormone receptor-negative and HER2-positive breast cancer had a complete pathological response after only three cycles of neoadjuvant systemic therapy. A complete response on breast MRI could help identify early complete responders in patients who had hormone receptor negative tumours. An imaging-based strategy might limit the duration of chemotherapy in these patients, reduce side-effects, and maintain quality of life if confirmed by the analysis of the 3-year event-free survival primary endpoint. Better monitoring tools are needed for patients with hormone receptor-positive and HER2-positive breast cancer.

FUNDING

Roche Netherlands.

Radiological, pathological and surgical outcomes after neoadjuvant endocrine treatment in patients with ER-positive/HER2-negative breast cancer with a clinical high risk and a low-risk 70-gene signature

OBJECTIVE

This study aims to evaluate the response to and surgical benefits of neoadjuvant endocrine therapy (NET) in ER+/HER2-breast cancer patients who are clinically high risk, but genomic low risk according to the 70-gene signature (MammaPrint).

METHODS

Patients with ER+/HER2-invasive breast cancer with a clinical high risk according to MINDACT, who had a genomic low risk according to the 70-gene signature and were treated with NET between 2015 and 2023 in our center, were retrospectively analyzed. RECIST 1.1 criteria were used to assess radiological response using MRI or ultrasound. Surgical specimens were evaluated to assess pathological response. Two breast cancer surgeons independently scored the eligibility of breast conserving therapy (BCS) pre- and post- NET.

RESULTS

Of 72 included patients, 23 were premenopausal (100% started with tamoxifen of which 4 also received OFS) and 49 were postmenopausal (98% started with an aromatase inhibitor). Overall, 8 (11%) showed radiological complete response. Only 1 (1.4%) patient had a pathological complete response (RCB-0) and 68 (94.4%) had a pathological partial response (RCB-1 or RCB-2). Among the 26 patients initially considered for mastectomy, 14 (53.8%) underwent successful BCS. In all 20 clinical node-positive patients, a marked axillary lymph node was removed to assess response. Four out of 20 (20%) patients had a pathological complete response of the axilla.

CONCLUSION

The study showed that a subgroup of patients with a clinical high risk and a genomic low risk ER+/HER2-breast cancer benefits from NET resulting in BCS instead of a mastectomy. Additionally, NET may enable de-escalation in axillary treatment.

Real-world data on malignant and borderline phyllodes tumors of the breast: A population-based study of all 921 cases in the Netherlands (1989 -2020)

AIM

The aim of our study is to analyze patterns in treatment and outcome in a population-based series of patients with borderline and malignant phyllodes tumors (PT).

MATERIAL AND METHODS

Data on all patients with a borderline or malignant PT (1989-2020) were extracted from the Netherlands Cancer Registry and the Dutch nationwide pathology databank (Palga) and retrospectively analyzed.

RESULTS

We included 921 patients (borderline PT n = 452 and malignant PT n = 469). Borderline PT patients more often had breast-conserving surgery (BCS) as final surgery (81 vs. 46%). BCS rates for borderline PT increased over time (OR 1.08 per year, 95%CI 1.04 - 1.13, P < 0.001). In malignant PT adjuvant radiotherapy was given in 14.7%; this rate increased over time (OR 1.07 per year, 95%CI 1.02 - 1.13, P = 0.012). Local recurrence rate (5-year estimate of cumulative incidence) was 8.7% (95%CI 6.0-11.4) for borderline PT and 11.7% (95%CI 8.6-14.8) for malignant PT (P = 0.187) and was related to tumor size ≥ 20 mm (HR 10.6 (95%CI 1.5-76.8) and positive margin (HR 3.0 (95%CI 1.6-5.6), p < 0.001), but not to negative margin width (HR 1.3 ( 95%CI 0.7-2.3), p = 0.350)). Distant metastasis occurred only in malignant PT with a 5-year cumulative incidence of 4.7% (95%CI 3.3 - 6.1).

CONCLUSION

This population-based series showed an increase in BCS in borderline PT and an increase in adjuvant radiotherapy in malignant PT over time. We identified malignant PT, BCS, larger tumor size and positive final margins as possible risk factors for local recurrence. Small but negative margins can be accepted.

Breast surgery after neoadjuvant chemotherapy in patients with lobular carcinoma: surgical and oncologic outcome

INTRODUCTION

Breast cancer patients with invasive lobular carcinoma (ILC) have an increased risk of positive margins after surgery and often show little response to neoadjuvant chemotherapy (NAC). We aimed to investigate surgical outcomes in patients with ILC treated with NAC.

METHODS

In this retrospective cohort study, all breast cancer patients with ILC treated with NAC who underwent surgery at the Netherlands Cancer Institute from 2010 to 2019 were selected. Patients with mixed type ILC in pre-NAC biopsies were excluded if the lobular component was not confirmed in the surgical specimen. Main outcomes were tumor-positive margins and re-excision rate. Associations between baseline characteristics and tumor-positive margins were assessed, as were complications, locoregional recurrence rate (LRR), recurrence-free survival (RFS), and overall survival (OS).

RESULTS

We included 191 patients. After NAC, 107 (56%) patients had breast conserving surgery (BCS) and 84 (44%) patients underwent mastectomy. Tumor-positive margins were observed in 67 (35%) patients. Fifty five (51%) had BCS and 12 (14%) underwent mastectomy (p value < 0.001). Re-excision was performed in 35 (33%) patients with BCS and in 4 (5%) patients with mastectomy. Definitive surgery was mastectomy in 107 (56%) patients and BCS in 84 (44%) patients. Tumor-positive margins were associated with cT ≥ 3 status (OR 4.62, 95% CI 1.26-16.98, p value 0.021) in the BCS group. Five-year LRR (4.7%), RFS (81%), and OS (93%) were not affected by type of surgery after NAC.

CONCLUSION

Although 33% of ILC breast cancer patients undergoing BCS after NAC required re-excision for positive resection margins, it is considered safe given that five-year RFS remained excellent and LRR and OS did not differ by extent of surgery.

Prognostic effect of nodal status before and after neoadjuvant chemotherapy in breast cancer: a Dutch population-based study

PURPOSE

In breast cancer, neoadjuvant chemotherapy (NAC) can downstage the nodal status, and can even result in a pathological complete response, which is associated with improved prognosis. This study aimed to determine the prognostic effect of nodal status before and after NAC.

METHODS

Women with breast cancer treated with NAC were selected from the Netherlands Cancer Registry if diagnosed between 2005 and 2019, and classified based on nodal status before NAC: node-negative (cN0), or node-positive based on fine needle aspiration cytology or core needle biopsy (cN+). Subgroups were based on nodal status after NAC: absence (ypN0) or presence (ypN+) of nodal disease. Five-year overall survival (OS) was assessed with Kaplan-Meier survival analyses, also per breast cancer molecular subtype. To adjust for potential confounders, multivariable analyses were performed.

RESULTS

A total of 6,580 patients were included in the cN0 group, and 11,878 in the cN+ group. The 5-year OS of the cN0ypN0-subgroup was statistically significant better than that of the cN+ypN0-subgroup (94.4% versus 90.1%, p < 0.0001). In cN0 as well as cN+ disease, ypN+ had a statistically significant worse 5-year OS compared to ypN0. For hormone receptor (HR)+ human epidermal growth factor receptor 2 (HER2)-, HR+ HER2+, HR-HER2+, and triple negative disease, respectively, 5-year OS in the cN0ypN+-subgroup was 89.7%, 90.4%, 73.7%, and 53.6%, and in the cN+ypN+-subgroup 84.7%, 83.2%, 61.4%, and 48.8%. In multivariable analyses, cN+ and ypN+ disease were both associated with worse OS.

CONCLUSION

This study suggests that both cN-status and ypN-status, and molecular subtype should be considered to further improve prognostication.

Systematic review of targeted axillary dissection in node-positive breast cancer treated with neoadjuvant systemic therapy: variation in type of marker and timing of placement

BACKGROUND

In node-positive (cN+) breast cancer treated with neoadjuvant systemic therapy, combining sentinel lymph node biopsy and targeted lymph node excision, that is targeted axillary dissection, increases accuracy. Targeted axillary dissection procedures differ in terms of the targeted lymph node excision technique. This systematic review aimed to provide an overview of targeted axillary dissection procedures regarding definitive marker type and timing of placement: before neoadjuvant systemic therapy (1-step procedure) or after neoadjuvant systemic therapy adjacent to a clip placed before the neoadjuvant therapy (2-step procedure).

METHODS

PubMed and Embase were searched, to 4 July 2023, for RCTs, cohort studies, and case-control studies with at least 25 patients. Studies of targeted lymph node excision only (without sentinel lymph node biopsy), or where intraoperative localization of the targeted lymph node was not attempted, were excluded. For qualitative synthesis, studies were grouped by definitive marker and timing of placement. The targeted lymph node identification rate was reported. Study quality was assessed using a National Institutes of Health quality assessment tool.

RESULTS

Of 277 unique records, 51 studies with a total of 4512 patients were included. Six definitive markers were identified: wire, 125I-labelled seed, 99mTc, (electro)magnetic/radiofrequency markers, black ink, and a clip. Fifteen studies evaluated one-step procedures, with the identification rate of the targeted lymph node at surgery varying from 8 of 13 to 47 of 47. Forty-one studies evaluated two-step procedures, with the identification rate of the clipped targeted lymph node on imaging after neoadjuvant systemic therapy varying from 49 to 100%, and the identification rate of the targeted lymph node at surgery from 17 of 24 to 100%. Most studies (40 of 51) were rated as being of fair quality.

CONCLUSION

Various targeted axillary dissection procedures are used in clinical practice. Owing to study heterogeneity, the optimal targeted lymph node excision technique in terms of identification rate and feasibility could not be determined. Two-step procedures are at risk of not identifying the clipped targeted lymph node on imaging after neoadjuvant systemic therapy.

Management of Benign Phyllodes Tumors: A Dutch Population-Based Retrospective Cohort Between 1989 and 2022

BACKGROUND

Phyllodes tumors (PTs) are rare tumors of the breast. The current National Comprehensive Cancer Network (NCCN) guidelines recommend excision of benign PTs, accepting close or positive margins. Controversy about the optimal treatment for benign PTs remains, especially regarding the preferred margin width after surgical excision and the need for follow-up evaluation.

METHODS

A nationwide retrospective study analyzed the Dutch population from 1989 to 2022. All patients with a diagnosis of benign PT were identified through a search in the Dutch nationwide pathology databank (Palga). Information on age, year of diagnosis, size of the primary tumor, surgical treatment, surgical margin status, and local recurrence was collected.

RESULTS

The study enrolled 1908 patients with benign PT. The median age at diagnosis was 43 years (interquartile range [IQR], 34-52 years), and the median tumor size was 30 mm (IQR, 19-40 mm). Most of the patients (95%) were treated with breast-conserving surgery (BCS). The overall local recurrence rate was 6.2%, and the median time to local recurrence was 31 months (IQR, 15-61 months). Local recurrence was associated with bilaterality of the tumor (odds ratio [OR], 4.91; 95% confidence interval [CI], 2.95-28.30) and positive margin status (OR, 2.51; 95% CI 1.36-4.63). The local recurrence rate was 8.9% for the patients with positive excision margins and 4.0% for the patients with negative excision margins. Notably, for 27 patients (22.6%) who experienced a local recurrence, histologic upgrading of the recurrent tumor was reported, 7 (5.9%) of whom had recurrence as malignant lesions.

CONCLUSIONS

This nationwide series of 1908 patients showed a low local recurrence rate of 6.2% for benign PT, with higher recurrence rates following positive margins.

This house believes that: MARI/TAD is better than sentinel node biopsy after PST for cN+ patients

The increasing use and effectiveness of primary systemic treatment (PST) enables tailored locoregional treatment. About one third of clinically node positive (cN+) breast cancer patients achieve pathologic complete response (pCR) of the axilla, with higher rates observed in Human Epidermal growth factor Receptor (HER)2-positive or triple negative (TN) breast cancer subtypes. Tailoring axillary treatment for patients with axillary pCR is necessary, as they are unlikely to benefit from axillary lymph node dissection (ALND), but may suffer complications and long-term morbidity such as lymphedema and impaired shoulder motion. By combining pre-PST and post-PST axillary staging techniques, ALND can be omitted in most cN + patients with pCR. Different post-PST staging techniques (MARI/TAD/SN) show low or ultra-low false negative rates for detection of residual disease. More importantly, trials using the MARI (Marking Axillary lymph nodes with Radioactive Iodine seeds) procedure or sentinel lymph node biopsy (SLNB) as axillary staging technique post-PST have already shown the safety of tailoring axillary treatment in patients with an excellent response. Tailored axillary treatment using the MARI procedure in stage I-III breast cancer resulted in 80% reduction of ALND and excellent five-year axillary recurrence free interval (aRFI) of 97%. Similar oncologic outcomes were seen for post-SLNB in stage I-II patients. The MARI technique requires only one invasive procedure pre-NST and a median of one node is removed post-PST, whereas for the SLNB and TAD techniques two to four nodes are removed. A disadvantage of the MARI technique is its use of radioactive iodine, which is subject to extensive regulations.

High-dose alkylating chemotherapy in BRCA-altered triple-negative breast cancer: the randomized phase III NeoTN trial

Exploratory analyses of high-dose alkylating chemotherapy trials have suggested that BRCA1 or BRCA2-pathway altered (BRCA-altered) breast cancer might be particularly sensitive to this type of treatment. In this study, patients with BRCA-altered tumors who had received three initial courses of dose-dense doxorubicin and cyclophosphamide (ddAC), were randomized between a fourth ddAC course followed by high-dose carboplatin-thiotepa-cyclophosphamide or conventional chemotherapy (initially ddAC only or ddAC-capecitabine/decetaxel [CD] depending on MRI response, after amendment ddAC-carboplatin/paclitaxel [CP] for everyone). The primary endpoint was the neoadjuvant response index (NRI). Secondary endpoints included recurrence-free survival (RFS) and overall survival (OS). In total, 122 patients were randomized. No difference in NRI-score distribution (p = 0.41) was found. A statistically non-significant RFS difference was found (HR 0.54; 95% CI 0.23-1.25; p = 0.15). Exploratory RFS analyses showed benefit in stage III (n = 35; HR 0.16; 95% CI 0.03-0.75), but not stage II (n = 86; HR 1.00; 95% CI 0.30-3.30) patients. For stage III, 4-year RFS was 46% (95% CI 24-87%), 71% (95% CI 48-100%) and 88% (95% CI 74-100%), for ddAC/ddAC-CD, ddAC-CP and high-dose chemotherapy, respectively. No significant differences were found between high-dose and conventional chemotherapy in stage II-III, triple-negative, BRCA-altered breast cancer patients. Further research is needed to establish if there are patients with stage III, triple negative BRCA-altered breast cancer for whom outcomes can be improved with high-dose alkylating chemotherapy or whether the current standard neoadjuvant therapy including carboplatin and an immune checkpoint inhibitor is sufficient. Trial Registration: NCT01057069.

Diffuse reflectance spectroscopy for accurate margin assessment in breast-conserving surgeries: importance of an optimal number of fibers

During breast-conserving surgeries, it remains challenging to accomplish adequate surgical margins. We investigated different numbers of fibers for fiber-optic diffuse reflectance spectroscopy to differentiate tumorous breast tissue from healthy tissue ex vivo up to 2 mm from the margin. Using a machine-learning classification model, the optimal performance was obtained using at least three emitting fibers (Matthew's correlation coefficient (MCC) of 0.73), which was significantly higher compared to the performance of using a single-emitting fiber (MCC of 0.48). The percentage of correctly classified tumor locations varied from 75% to 100% depending on the tumor percentage, the tumor-margin distance and the number of fibers.

Biopsy-Guided Pathological Response Assessment in Breast Cancer is Insufficient: Additional Pathology Findings of the MICRA Trial

BACKGROUND

Neoadjuvant systemic treatment (NST) leads to pathologic complete response (pCR) in 10-89% of breast cancer patients depending on subtype. The added value of surgery is uncertain in patients who reach pCR; however, current imaging and biopsy techniques aiming to predict pCR are not accurate enough. This study aims to quantify the residual disease remaining after NST in patients with a favorable response on MRI and residual disease missed with biopsies.

METHODS

In the MICRA trial, patients with a favorable response to NST on MRI underwent ultrasound-guided post-NST 14G biopsies followed by surgery. We analyzed pathology reports of the biopsies and the surgical specimens. Primary outcome was the extent of residual invasive disease among molecular subtypes, and secondary outcome was the extent of missed residual invasive disease.

RESULTS

We included 167 patients. Surgical specimen showed residual invasive disease in 69 (41%) patients. The median size of residual invasive disease was 18 mm (interquartile range [IQR] 12-30) in hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) patients, 8 mm (IQR 3-15) in HR+/HER2-positive (HER2+) patients, 4 mm (IQR 2-9) in HR-negative (HR-)/HER2+ patients, and 5 mm (IQR 2-11) in triple-negative (TN) patients. Residual invasive disease was missed in all subtypes varying from 4 to 7 mm.

CONCLUSION

Although the extent of residual invasive disease is small in TN and HER2+ subtypes, substantial residual invasive disease is left behind in all subtypes with 14G biopsies. This may hamper local control and limits adjuvant systemic treatment options. Therefore, surgical excision remains obligatory until accuracy of imaging and biopsy techniques improve.

The Safe Use of 125I-Seeds as a Localization Technique in Breast Cancer during Pregnancy

INTRODUCTION

Some aspects of the treatment protocol for breast cancer during pregnancy (PrBC) have not been thoroughly studied. This study provides clarity regarding the safety of the use of ¹²⁵I-seeds as a localization technique for breast-conserving surgery in patients with PrBC.

METHODS

To calculate the exposure to the fetus of one ¹²⁵I-seed implanted in a breast tumor, we developed a model accounting for the decaying ¹²⁵I-source, time to surgery, and the declining distance between the ¹²⁵I-seed and the fetus. The primary outcome was the maximum cumulative fetal dose of radiation at consecutive gestational ages (GA).

RESULTS

The cumulative fetal dose remains below 1 mSv if a single ¹²⁵I-seed is implanted at a GA of 26 weeks. After a GA of 26 weeks, the fetal dose can be at a maximum of 11.6 mSv. If surgery takes place within two weeks of implantation from a GA of 26 weeks, and one week above a GA of 32 weeks, the dose remains below 1 mSv.

CONCLUSION

The use of ¹²⁵I-seeds is safe in PrBC. The maximum fetal exposure remains well below the threshold of 100 mSv, and therefore, does not lead to an increased risk of fetal tissue damage. Still, we propose keeping the fetal dose as low as possible, preferably below 1 mSv.

The Areola study: design and rationale of a cohort study on long-term health outcomes in women with implant-based breast reconstructions

BACKGROUND

Implant-based breast reconstructions contribute considerably to the quality of life of breast cancer patients. A knowledge gap exists concerning the potential role of silicone breast implants in the development of so called 'breast implant illness' and autoimmune diseases in breast cancer survivors with implant-based reconstructions. Breast implant illness (BII) is a constellation of non-specific symptoms reported by a small group of women with silicone breast implants.

METHODS/DESIGN

The Areola study is a multi-centre retrospective cohort study with prospective follow-up aiming to assess the risk of BII and autoimmune diseases in female breast cancer survivors with and without silicone breast implants. In this report, we set out the rationale, study design and methodology of this cohort study. The cohort consists of breast cancer survivors who received surgical treatment with implant-based reconstruction in six major hospitals across the Netherlands in the period between 2000 and 2015. As comparison group, a frequency-matched sample of breast cancer survivors without breast implants will be selected. An additional group of women who received breast augmentation surgery in the same years will be selected to compare their characteristics and health outcomes with those of breast cancer patients with implants. All women still alive will be invited to complete a web-based questionnaire covering health-related topics. The entire cohort including deceased women will be linked to population-based databases of Statistics Netherlands. These include a registry of hospital diagnostic codes, a medicines prescription registry and a cause-of-death registry, through which diagnoses of autoimmune diseases will be identified. Outcomes of interest are the prevalence and incidence of BII and autoimmune diseases. In addition, risk factors for the development of BII and autoimmune disorders will be assessed among women with implants.

DISCUSSION

The Areola study will contribute to the availability of reliable information on the risks of BII and autoimmune diseases in Dutch breast cancer survivors with silicone breast implants. This will inform breast cancer survivors and aid future breast cancer patients and their treating physicians to make informed decisions about reconstructive strategies after mastectomy.

REGISTRATION

This study is registered at ClinicalTrials.gov on June 2^nd 2022 (NCT05400954).

Immediate or delayed oncoplastic surgery after breast conserving surgery at the Netherlands Cancer Institute: a cohort study of 251 cases

PURPOSE

Oncoplastic surgery (OPS) after breast conserving surgery is preferably performed during the same operation. Offering delayed OPS instead of mastectomy to patients with a high risk of tumor-positive margins allows breast conservation with the option of margin re-excision during OPS, without having to dismantle the reconstruction. We aimed to evaluate surgical outcomes after immediate and delayed OPS.

METHODS

We included early-stage breast cancer patients who underwent OPS at the Netherlands Cancer Institute between 2016 and 2019. Patients were selected for delayed OPS after multidisciplinary consultation if the risk of tumor-positive margins with immediate OPS was considered significant (> 30%). Groups were compared on baseline characteristics and short-term surgical outcomes.

RESULTS

Of 242 patients with 251 OPS, 130 (52%) OPS had neoadjuvant chemotherapy. Immediate OPS was performed in 176 (70%) cases and delayed OPS in 76 (30%). Selection for delayed OPS was associated with tumor size (OR 1.03, 95% CI 1.01-1.04), ILC (OR 2.61, 95% CI 1.10-6.20), DCIS (OR 3.45, 95% CI 1.42-8.34) and bra size (OR 0.76, 95% CI 0.62-0.94). Delayed and immediate OPS differed in tissue weight (54 vs. 67 g, p = 0.034), tissue replacement (51% vs. 26%, p < .001) and tumor-positive margins (66% vs. 18%, p < .001). Re-excision was performed in 48 (63%) delayed OPS and in 11 (6%) immediate OPS. Groups did not differ in complications (21% vs. 18%, p = 0.333). Breast conservation after immediate and delayed OPS was 98% and 93%, respectively.

CONCLUSION

Performing delayed OPS in selected cases facilitated simultaneous margin re-excision without increasing complications, and resulted in an excellent breast conservation rate.

De-ESCAlating RadioTherapy in breast cancer patients with pathologic complete response to neoadjuvant systemic therapy: DESCARTES study

PURPOSE

Neoadjuvant systemic therapy (NST) is increasingly used in breast cancer patients and depending on subtype, 10-89% of patients will attain pathologic complete response (pCR). In patients with pCR, risk of local recurrence (LR) after breast conserving therapy is low. Although adjuvant radiotherapy after breast conserving surgery (BCS) reduces LR further in these patients, it may not contribute to overall survival. However, radiotherapy may cause early and late toxicity. The aim of this study is to show that omission of adjuvant radiotherapy in patients with a pCR after NST will result in acceptable low LR rates and good quality of life.

METHODS

The DESCARTES study is a prospective, multicenter, single arm study. Radiotherapy will be omitted in cT1-2N0 patients (all subtypes) who achieve a pCR of the breast and lymph nodes after NST followed by BCS plus sentinel node procedure. A pCR is defined as ypT0N0 (i.e. no residual tumor cells detected). Primary endpoint is the 5-year LR rate, which is expected to be 4% and deemed acceptable if less than 6%. In total, 595 patients are needed to achieve a power of 80% (one-side alpha of 0.05). Secondary outcomes include quality of life, Cancer Worry Scale, disease specific and overall survival. Projected accrual is five years.

CONCLUSION

This study bridges the knowledge gap regarding LR rates when adjuvant radiotherapy is omitted in cT1-2N0 patients achieving pCR after NST. If the results are positive, radiotherapy may be safely omitted in selected breast cancer patients with a pCR after NST.

TRIAL REGISTRATION

This study is registered at ClinicalTrials.gov on June 13th 2022 (NCT05416164). Protocol version 5.1 (15-03-2022).

Toward Intraoperative Margin Assessment Using a Deep Learning-Based Approach for Automatic Tumor Segmentation in Breast Lumpectomy Ultrasound Images

There is an unmet clinical need for an accurate, rapid and reliable tool for margin assessment during breast-conserving surgeries. Ultrasound offers the potential for a rapid, reproducible, and non-invasive method to assess margins. However, it is challenged by certain drawbacks, including a low signal-to-noise ratio, artifacts, and the need for experience with the acquirement and interpretation of images. A possible solution might be computer-aided ultrasound evaluation. In this study, we have developed new ensemble approaches for automated breast tumor segmentation. The ensemble approaches to predict positive and close margins (distance from tumor to margin ≤ 2.0 mm) in the ultrasound images were based on 8 pre-trained deep neural networks. The best optimum ensemble approach for segmentation attained a median Dice score of 0.88 on our data set. Furthermore, utilizing the segmentation results we were able to achieve a sensitivity of 96% and a specificity of 76% for predicting a close margin when compared to histology results. The promising results demonstrate the capability of AI-based ultrasound imaging as an intraoperative surgical margin assessment tool during breast-conserving surgery.

[Breast cancer; article for education and training purposes]

Breast cancer is the most commonly occurring malignancy in women. Every year, this type of cancer is newly diagnosed in almost 15,000 women and over 100 men in the Netherlands. Survival depends on the stage of disease and has improved over time. However, every year approximately 3100 women die of breast cancer in the Netherlands. Recent developments in breast cancer care focus on more breast and axilla conserving treatments, and the omission or more limited application of adjuvant chemotherapy or additional radiotherapy if it is deemed safe. In this educational article we discuss aspects of detection, diagnosis, treatment and follow-up of breast cancer.

Short-Term Surgical Complications of Skin-Sparing Mastectomy and Direct-to-Implant Immediate Breast Reconstruction in Women Concurrently Treated with Adjuvant Radiotherapy for Breast Cancer

Background  Postmastectomy radiotherapy (PMRT) is allegedly associated with a higher risk of complications of combined nipple-sparing or skin-sparing mastectomy and subpectoral direct-to-implant immediate breast reconstruction ([N]SSM/SDTI-IBR). For this reason, this combination is usually advised against or, even, refused in women who need to undergo PMRT. Because this advice has never been justified, we assessed the short-term complications that may potentially be associated with PMRT after [N]SSM/SDTI-IBR.

Methods  We compared the complications requiring reintervention and implant loss occurring after 273 [N]SSM/SDTI-IBR that were exposed to PMRT within the first 16 postoperative weeks (interventional group) to those occurring in 739 similarly operated breasts that were not (control group). Additionally, we compared the fraction of complications requiring reintervention occurring after the onset of radiotherapy in the interventional group to that occurring after a comparable postoperative period in the control group.

Results  The fraction of breasts requiring unscheduled surgical reinterventions for complications and the loss of implants did not differ significantly between both groups but significantly more reinterventions were needed among the controls ( p  = 0.00). The fraction of events after the onset of radiotherapy in the interventional group was higher than the fraction of events after 6.2 weeks in the control group, but not significantly so.

Conclusion  We found no prove for the alleged increase of short-term complications of adjuvant radiotherapy. Therefore, we advise that these should not be considered valid arguments to advice against [N]SSM/SDTI-IBR.

Discriminating healthy from tumor tissue in breast lumpectomy specimens using deep learning-based hyperspectral imaging

Achieving an adequate resection margin during breast-conserving surgery remains challenging due to the lack of intraoperative feedback. Here, we evaluated the use of hyperspectral imaging to discriminate healthy tissue from tumor tissue in lumpectomy specimens. We first used a dataset obtained on tissue slices to develop and evaluate three convolutional neural networks. Second, we fine-tuned the networks with lumpectomy data to predict the tissue percentages of the lumpectomy resection surface. A MCC of 0.92 was achieved on the tissue slices and an RMSE of 9% on the lumpectomy resection surface. This shows the potential of hyperspectral imaging to classify the resection margins of lumpectomy specimens.

Transparency in quality of radiotherapy for breast cancer in the Netherlands: a national registration of radiotherapy-parameters

Background

Radiotherapy (RT) is part of the curative treatment of approximately 70% of breast cancer (BC) patients. Wide practice variation has been reported in RT dose, fractionation and its treatment planning for BC. To decrease this practice variation, it is essential to first gain insight into the current variation in RT treatment between institutes. This paper describes the development of the NABON Breast Cancer Audit-Radiotherapy (NBCA-R), a structural nationwide registry of BC RT data of all BC patients treated with at least surgery and RT.

Methods

A working group consisting of representatives of the BC Platform of the Dutch Radiotherapy Society selected a set of dose volume parameters deemed to be surrogate outcome parameters, both for tumour control and toxicity. Two pilot studies were carried out in six RT institutes. In the first pilot study, data were manually entered into a secured web-based system. In the second pilot study, an automatic Digital Imaging and Communications in Medicine (DICOM) RT upload module was created and tested.

Results

The NBCA-R dataset was created by selecting RT parameters describing given dose, target volumes, coverage and homogeneity, and dose to organs at risk (OAR). Entering the data was made mandatory for all Dutch RT departments. In the first pilot study (N = 1093), quite some variation was already detected. Application of partial breast irradiation varied from 0 to 17% between the 6 institutes and boost to the tumour bed from 26.5 to 70.2%. For patients treated to the left breast or chest wall only, the average mean heart dose (MHD) varied from 0.80 to 1.82 Gy; for patients treated to the breast/chest wall only, the average mean lung dose (MLD) varied from 2.06 to 3.3 Gy. In the second pilot study 6 departments implemented the DICOM-RT upload module in daily practice. Anonymised data will be available for researchers via a FAIR (Findable, Accessible, Interoperable, Reusable) framework.

Conclusions

We have developed a set of RT parameters and implemented registration for all Dutch BC patients. With the use of an automated upload module registration burden will be minimized. Based on the data in the NBCA-R analyses of the practice variation will be done, with the ultimate aim to improve quality of BC RT.

Trial registration Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02043-0.

Three-year follow-up of de-escalated axillary treatment after neoadjuvant systemic therapy in clinically node-positive breast cancer: the MARI-protocol

Purpose

In clinically node-positive (cN+) breast cancer patients, evidence supporting response-guided treatment after neoadjuvant systemic therapy (NST) instead of axillary lymph node dissection (ALND) is increasing, but follow-up results are lacking. We assessed three-year axillary recurrence-free interval (aRFI) in cN+ patients with response-adjusted axillary treatment according to the ‘Marking Axillary lymph nodes with Radioactive Iodine seeds’ (MARI)-protocol.

Methods

We retrospectively assessed all stage II–III cytologically proven cN+ breast cancer patients who underwent the MARI-protocol between July 2014 and November 2018. Pre-NST axillary staging with FDG-PET/CT (less- or more than four suspicious axillary nodes; cALN < 4 or cALN ≥ 4) and post-NST pathological axillary response measured in the pre-NST largest tumor-positive axillary lymph node marked with an iodine seed (MARI-node; ypMARI-neg or ypMARI-pos) determined axillary treatment: no further treatment (cALN < 4, ypMARI-neg), axillary radiotherapy (ART) (cALN < 4, ypMARI-pos and cALN ≥ 4, ypMARI-neg) or ALND plus ART (cALN ≥ 4, ypMARI-pos).

Results

Of 272 women included, the MARI-node was tumor-negative in 56 (32%) of 174 cALN < 4 patients and 43 (44%) of 98 cALN ≥ 4 patients. According to protocol, 56 (21%) patients received no further axillary treatment, 161 (59%) received ART and 55 (20%) received ALND plus ART. Median follow-up was 3.0 years (IQR 1.9–4.1). Five patients (one no further treatment, four ART) had axillary metastases. Three-year aRFI was 98% (95% CI 96–100). The overall recurrence risk remained highest for patients with ALND (HR 4.36; 95% CI 0.95–20.04, p = 0.059).

Conclusions

De-escalation of axillary treatment according to the MARI-protocol prevented ALND in 80% of cN+ patients with an excellent three-year aRFI of 98%.

De-Escalating Axillary Surgery in Node-Positive Breast Cancer Treated with Neoadjuvant Systemic Therapy

Background

There is a trend towards de-escalating axillary staging and treatment in breast cancer patients. On account of neoadjuvant systemic therapy, node-positive breast cancer patients can achieve a pathological complete response of the axilla. It is hypothesized that these patients do not benefit from an axillary lymph node dissection (ALND), and thus may be spared the risk of severe post-surgical morbidity. In an effort to omit standard ALND, less invasive axillary staging procedures are being implemented to establish response-guided treatment. However, it is unclear which less invasive staging procedure is most accurate, and long-term data are missing with regard to their oncologic safety.

Summary

This article provides an overview of the literature on currently used less invasive axillary staging procedures, the accuracy and feasibility of these procedures in clinical practice, important issues concerning axillary treatment, and issues to be addressed in ongoing or future studies.

Key messages

More evidence is needed regarding the safety of replacing standard ALND by less invasive axillary staging procedures in terms of long-term prognosis. These less invasive staging procedures not only serve to select patients who may benefit from treatment de-escalation, but also to select patients who may benefit from treatment escalation.

[18F]FDG-PET/CT in prone compared to supine position for optimal axillary staging and treatment in clinically node-positive breast cancer patients with neoadjuvant systemic therapy

PURPOSE

Axillary staging before neoadjuvant systemic therapy in clinically node-positive breast cancer patients with tailored axillary treatment according to the Marking Axillary lymph nodes with radioactive iodine seeds (MARI)-protocol, a protocol developed at the Netherlands Cancer Institute, is performed with [¹⁸F] fluorodeoxyglucose (FDG) positron emission tomography and computed tomography (PET/CT). We aimed to assess the value of FDG-PET/CT in prone compared to standard supine position for axillary staging.

METHODS

We selected patients with FDG-PET/CT in supine and prone position who underwent the MARI-protocol. One hour after administration of 3.5 MBq/kg, [¹⁸F]FDG-PET was performed with a low-dose prone position CT-thorax followed by a supine whole-body scan. Scans were separately reviewed by two nuclear medicine physicians and categorized by number of FDG-positive axillary lymph nodes (ALNs; cALN<4 or cALN≥4). Main outcome was axillary up- or downstaging.

RESULTS

Of 153 patients included, 24 (16%) patients were up- or downstaged at evaluation of prone images: One observer upstaged 14 patients, downstaged 3  patients and reported a higher number of ALNs (3.6 vs. 3.2, p < 0.001), while staging (4 up- and 5 downstaged) and number of ALNs (2.8 vs. 2.8) did not differ for the other. Observers agreed on up- or downstaging in only 1 (1%) patient. Irrespective of supine or prone position scanning, observers agreed on axillary staging in 124 (81%) patients and disagreed in 5 (3%). Interobserver agreement was lower with prone assessments (86%, K = 0.67) than supine (92%, K = 0.80).

CONCLUSIONS

Axillary staging with FDG-PET/CT in prone compared to supine position did not result in concordant up- or downstaging. Therefore, FDG-PET/CT in supine position only can be considered sufficient for axillary staging.

MINImal vs. MAXimal Invasive Axillary Staging and Treatment After Neoadjuvant Systemic Therapy in Node Positive Breast Cancer: Protocol of a Dutch Multicenter Registry Study (MINIMAX)

BACKGROUND

Node positive breast cancer (cN+) patients with an axillary pathologic complete response after neoadjuvant systemic therapy (NST) are not expected to benefit from axillary lymph node dissection (ALND). Therefore, less invasive axillary staging procedures have been introduced to establish response-guided treatment. However, evidence is lacking with regard to their oncologic safety and impact on quality of life (QoL). We hypothesize that if response-guided treatment is given, less invasive staging procedures are non-inferior to standard ALND in terms of oncologic safety, and superior to standard ALND in terms of QoL.

PATIENTS AND METHODS

MINIMAX is a Dutch multicenter registry study that includes patients with cN1-3M0 unilateral invasive breast cancer, who receive NST, followed by axillary staging and treatment according to local protocols. In a retrospective registry of ±4000 patients, the primary endpoint is oncologic safety at 5 and 10 years (disease-free, breast-cancer-specific and overall survival, and axillary recurrence rate). In a prospective multicenter registry, the primary endpoints are QoL at 1 and 5 years, and we aim to verify the 5-year oncologic safety. With an estimated 5-year disease-free survival of 72.5% and anticipated loss to follow-up of 10%, a sample size of 549 is needed to have 80% power to detect non-inferiority (with a 10% margin) of less invasive staging procedures.

CONCLUSION

In cN+ patients treated with NST, less invasive axillary staging procedures are already implemented globally. Evidence is needed to support the assumed oncologic safety and superior QoL of such procedures. This study will contribute to evidence-based guidelines.

Minimally Invasive Complete Response Assessment of the Breast After Neoadjuvant Systemic Therapy for Early Breast Cancer (MICRA trial): Interim Analysis of a Multicenter Observational Cohort Study

BACKGROUND

The added value of surgery in breast cancer patients with pathological complete response (pCR) after neoadjuvant systemic therapy (NST) is uncertain. The accuracy of imaging identifying pCR for omission of surgery, however, is insufficient. We investigated the accuracy of ultrasound-guided biopsies identifying breast pCR (ypT0) after NST in patients with radiological partial (rPR) or complete response (rCR) on MRI.

METHODS

We performed a multicenter, prospective single-arm study in three Dutch hospitals. Patients with T1-4(N0 or N +) breast cancer with MRI rPR and enhancement ≤ 2.0 cm or MRI rCR after NST were enrolled. Eight ultrasound-guided 14-G core biopsies were obtained in the operating room before surgery close to the marker placed centrally in the tumor area at diagnosis (no attempt was made to remove the marker), and compared with the surgical specimen of the breast. Primary outcome was the false-negative rate (FNR).

RESULTS

Between April 2016 and June 2019, 202 patients fulfilled eligibility criteria. Pre-surgical biopsies were obtained in 167 patients, of whom 136 had rCR and 31 had rPR on MRI. Forty-three (26%) tumors were hormone receptor (HR)-positive/HER2-negative, 64 (38%) were HER2-positive, and 60 (36%) were triple-negative. Eighty-nine patients had pCR (53%; 95% CI 45-61) and 78 had residual disease. Biopsies were false-negative in 29 (37%; 95% CI 27-49) of 78 patients. The multivariable associated with false-negative biopsies was rCR (FNR 47%; OR 9.81, 95% CI 1.72-55.89; p = 0.01); a trend was observed for HR-negative tumors (FNR 71% in HER2-positive and 55% in triple-negative tumors; OR 4.55, 95% CI 0.95-21.73; p = 0.058) and smaller pathological lesions (6 mm vs 15 mm; OR 0.93, 95% CI 0.87-1.00; p = 0.051).

CONCLUSION

The MICRA trial showed that ultrasound-guided core biopsies are not accurate enough to identify breast pCR in patients with good response on MRI after NST. Therefore, breast surgery cannot safely be omitted relying on the results of core biopsies in these patients.

Breast-Conserving Therapy in Patients with cT3 Breast Cancer with Good Response to Neoadjuvant Systemic Therapy Results in Excellent Local Control: A Comprehensive Cancer Center Experience

BACKGROUND

Many cT3 breast cancer patients are treated with mastectomy, regardless of response to neoadjuvant systemic therapy (NST). We evaluated local control of cT3 patients undergoing breast-conserving therapy (BCT) based on magnetic resonance imaging (MRI) evaluation post-NST. In addition, we analyzed predictive characteristics for positive margins after breast-conserving surgery (BCS).

METHODS

All cT3 breast cancer patients who underwent BCS after NST between 2002 and 2015 at the Netherlands Cancer Institute were included. Local recurrence-free interval (LRFI) was estimated using the Kaplan-Meier method, and predictors for positive margins were analyzed using univariable analysis and multivariable logistic regression.

RESULTS

Of 114 patients undergoing BCS post-NST, 75 had negative margins, 16 had focally positive margins, and 23 had positive margins. Of those with (focally) positive margins, 12 underwent radiotherapy, 6 underwent re-excision, and 21 underwent mastectomy. Finally, 93/114 patients were treated with BCT (82%), with an LRFI of 95.9% (95% confidence interval [CI] 91.5-100%) after a median follow-up of 7 years. Predictors for positive margins in univariable analysis were hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) subtype, lobular carcinoma, and non-mass enhancement (NME) on pre-NST MRI. MRI response was not correlated to positive margins. In multivariable regression, the odds of positive margins were decreased in patients with HER2-positive (HER2+; odds ratio [OR] 0.27, 95% CI 0.10-0.73; p = 0.01) and TN tumors (OR 0.17, 95% CI 0.03-0.82; p = 0.028). A trend toward positive margins was observed in patients with NME (OR 2.38, 95% CI 0.98-5.77; p = 0.055).

CONCLUSION

BCT could be performed in 82% of cT3 patients in whom BCT appeared feasible on post-NST MRI. Local control in these patients was excellent. In those patients with HR+/HER2- tumors, NME on MRI, or invasive lobular carcinoma, the risk of positive margins should be considered preoperatively.

Impact of the COVID-19 pandemic on diagnosis, stage, and initial treatment of breast cancer in the Netherlands: a population-based study

BACKGROUND

The onset of the COVID-19 pandemic forced the Dutch national screening program to a halt and increased the burden on health care services, necessitating the introduction of specific breast cancer treatment recommendations from week 12 of 2020. We aimed to investigate the impact of COVID-19 on the diagnosis, stage and initial treatment of breast cancer.

METHODS

Women included in the Netherlands Cancer Registry and diagnosed during four periods in weeks 2-17 of 2020 were compared with reference data from 2018/2019 (averaged). Weekly incidence was calculated by age group and tumor stage. The number of women receiving initial treatment within 3 months of diagnosis was calculated by period, initial treatment, age, and stage. Initial treatment, stratified by tumor behavior (ductal carcinoma in situ [DCIS] or invasive), was analyzed by logistic regression and adjusted for age, socioeconomic status, stage, subtype, and region. Factors influencing time to treatment were analyzed by Cox regression.

RESULTS

Incidence declined across all age groups and tumor stages (except stage IV) from 2018/2019 to 2020, particularly for DCIS and stage I disease (p < 0.05). DCIS was less likely to be treated within 3 months (odds ratio [OR]wks2-8: 2.04, ORwks9-11: 2.18). Invasive tumors were less likely to be treated initially by mastectomy with immediate reconstruction (ORwks12-13: 0.52) or by breast conserving surgery (ORwks14-17: 0.75). Chemotherapy was less likely for tumors diagnosed in the beginning of the study period (ORwks9-11: 0.59, ORwks12-13: 0.66), but more likely for those diagnosed at the end (ORwks14-17: 1.31). Primary hormonal treatment was more common (ORwks2-8: 1.23, ORwks9-11: 1.92, ORwks12-13: 3.01). Only women diagnosed in weeks 2-8 of 2020 experienced treatment delays.

CONCLUSION

The incidence of breast cancer fell in early 2020, and treatment approaches adapted rapidly. Clarification is needed on how this has affected stage migration and outcomes.

Breast conservation and axillary management after primary systemic therapy in patients with early-stage breast cancer: the Lucerne toolbox

Primary systemic therapy is increasingly used in the treatment of patients with early-stage breast cancer, but few guidelines specifically address optimal locoregional therapies. Therefore, we established an international consortium to discuss clinical evidence and to provide expert advice on technical management of patients with early-stage breast cancer. The steering committee prepared six working packages to address all major clinical questions from diagnosis to surgery. During a consensus meeting that included members from European scientific oncology societies, clinical trial groups, and patient advocates, statements were discussed and voted on. A consensus was reached in 42% of statements, a majority in 38%, and no decision in 21%. Based on these findings, the panel developed clinical guidance recommendations and a toolbox to overcome many clinical and technical requirements associated with the diagnosis, response assessment, surgical planning, and surgery of patients with early-stage breast cancer. This guidance could convince clinicians and patients of the major clinical advancements purported by primary systemic therapy, the use of less extensive and more targeted surgery to improve the lives of patients with breast cancer.

Effect of Case-Mix and Random Variation on Breast Cancer Care Quality Indicators and Their Rankability

OBJECTIVES

Hospital comparisons to improve quality of care require valid and reliable quality indicators. We aimed to test the validity and reliability of 6 breast cancer indicators by quantifying the influence of case-mix and random variation.

METHODS

The nationwide population-based database included 79 690 patients with breast cancer from 91 Dutch hospitals between 2011 and 2016. The indicator-scores calculated were: (1) irradical breast-conserving surgery (BCS) for invasive disease, (2) irradical BCS for ductal carcinoma-in-situ, (3) breast contour-preserving treatment, (4) magnetic resonance imaging (MRI) before neo-adjuvant chemotherapy, (5) radiotherapy for locally advanced disease, and (6) surgery within 5 weeks from diagnosis. Case-mix and random variation adjustments were performed by multivariable fixed and random effect logistic regression models. Rankability quantified the between-hospital variation, representing unexplained differences that might be the result of the level of quality of care, as low (<50%), moderate (50%-75%), or high (>75%).

RESULTS

All of the indicators showed between-hospital variation with wide (interquartile) ranges. Case-mix adjustment reduced variation in indicators 1 and 3 to 5. Random variation adjustment (further) reduced the variation for all indicators. Case-mix and random variation adjustments influenced the indicator-scores of individual hospitals and their ranking. Rankability was poor for indicator 1, 2, and 5, and moderate for 3, 4, and 6.

CONCLUSIONS

The 6 indicators lacked validity and/or reliability to a certain extent. Although measuring quality indicators may stimulate quality improvement in general, comparisons and judgments of individual hospital performance should be made with caution if based on indicators that have not been tested or adjusted for validity and reliability, especially in benchmarking.

From Multiple Quality Indicators of Breast Cancer Care Toward Hospital Variation of a Summary Measure

OBJECTIVES

To improve quality in breast cancer care, large numbers of quality indicators are collected per hospital, but benchmarking remains complex. We aimed to assess the validity of indicators, develop a textbook outcome summary measure, and compare case-mix adjusted hospital performance.

METHODS

From a nationwide population-based registry, all 79 690 nonmetastatic breast cancer patients surgically treated between 2011 and 2016 in 91 hospitals in The Netherlands were included. Twenty-one indicators were calculated and their construct validity tested by Spearman's rho. Between-hospital variation was expressed by interquartile range (IQR), and all valid indicators were included in the summary measure. Standardized scores (observed/expected based on case mix) were calculated as above (>100) or below (<100) expected. The textbook outcome was presented as a continuous and all-or-none score.

RESULTS

The size of between-hospital variation varied between indicators. Sixteen (76%) of 21 quality indicators showed construct validity, and 13 were included in the summary measure after excluding redundant indicators that showed collinearity with others owing to strong construct validity. The median all-or-none textbook outcome score was 49% (IQR 42%-54%) before and 49% (IQR 48%-51%) after case-mix adjustment. From the total of 91 hospitals, 3 hospitals were positive (3%) and 9 (10%) were negative outliers.

CONCLUSIONS

The textbook outcome summary measure showed discriminative ability when hospital performance was presented as an all-or-none score. Although indicator scores and outlier hospitals should always be interpreted cautiously, the summary measure presented here has the potential to improve Dutch breast cancer quality indicator efforts and could be implemented to further test its validity, feasibility, and usefulness.

Local staging of ipsilateral breast tumor recurrence: mammography, ultrasound, or MRI?

BACKGROUND

Despite increasingly effective curative breast-conserving treatment (BCT) regimens for primary breast cancer, patients remain at risk for an ipsilateral breast tumor recurrence (IBTR). With increasing interest for repeat BCT in selected patients with IBTR, a reliable assessment of the size of IBTR is important for surgical planning.

AIM

The primary aim of this study is to establish the performance in size estimation of XMG, US, and breast MRI in patients with IBTR. The secondary aim is to compare the detection of multifocality and contralateral lesions between XMG and MRI.

PATIENTS AND METHODS

The sizes of IBTR on mammography (XMG), ultrasound (US), and magnetic resonance imaging (MRI) in 159 patients were compared to the sizes at final histopathology. The accuracy of the size estimates was addressed using Pearson's coefficient and Bland-Altman plots. Secondary outcomes were the detection of multifocality and contralateral lesions between XMG and MRI.

RESULTS

Both XMG and US significantly underestimated the tumor size by 3.5 and 4.8 mm, respectively, while MRI provided accurate tumor size estimation with a mean underestimation of 1.1 mm. The sensitivity for the detection of multifocality was significantly higher for MRI compared to XMG (25.5% vs. 5.5%). A contralateral malignancy was found in 4.4% of patients, and in 1.9%, it was detected by MRI only.

CONCLUSION

The addition of breast MRI to XMG and US in the preoperative workup of IBTR allows for more accurate size estimation. MRI provides a higher sensitivity for the detection of multifocality compared to XMG.

Association between initiation of adjuvant chemotherapy beyond 30 days after surgery and overall survival among patients with triple-negative breast cancer

Delayed time to chemotherapy (TTC) is associated with decreased outcomes of breast cancer patients. Recently, studies suggested that the association might be subtype‐dependent and that TTC within 30 days should be warranted in patients with triple‐negative breast cancer (TNBC). The aim of the current study is to determine if TTC beyond 30 days is associated with reduced 10‐year overall survival in TNBC patients. We identified all TNBC patients diagnosed between 2006 and 2014 who received adjuvant chemotherapy in the Netherlands. We distinguished between breast‐conserving surgery (BCS) vs. mastectomy given the difference in preoperative characteristics and outcomes. The association was estimated with hazard ratios (HRs) using propensity‐score matched Cox proportional hazard analyses. In total, 3,016 patients were included. In matched patients who underwent BCS (n = 904), 10‐year overall survival was favorable for patients with TTC within 30 days (84.4% vs. 76.9%, p = 0.001). Patients with TTC beyond 30 days were more likely than those with TTC within 30 days to die within 10 years after surgery (HR 1.69 (95% CI 1.22–2.34), p = 0.002). In matched patients who underwent mastectomy (n = 1,568), there was no difference in 10 years overall survival between those with TTC within or beyond 30 days (74.5% vs. 74.7%, p = 0.716), nor an increased risk of death for those with TTC beyond 30 days (HR 1.04 (95% CI 0.84–1.28), p = 0.716). Initiation of adjuvant chemotherapy beyond 30 days is associated with decreased 10 years overall survival in TNBC patients who underwent BCS. Therefore, timelier initiation of chemotherapy in TNBC patients undergoing BCS seems warranted.

What's new?

Current breast cancer treatment guidelines recommend that chemotherapy is initiated between 6‐12 weeks after surgery. Delayed treatment can lead to poorer outcome, but there's no precise definition of the optimal window. Recent work suggests that for patients with triple negative breast cancer (TNBC), it's best to initiate chemotherapy within 30 days. Here, the authors evaluated outcomes for TNBC patients correlated with time to chemotherapy. They found that in patients undergoing breast‐conserving surgery, an interval of more than 30 days before chemotherapy was associated with decreased survival. If the patient had undergone a mastectomy, a longer delay before chemotherapy did not impact survival.

Multifocality in ipsilateral breast tumor recurrence - A study in ablative specimens

BACKGROUND

The incidence and clinical significance of multifocality in ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy (BCT) are unclear. With growing interest in repeat BCT, this information has become of importance. This study aimed to gain insight in the incidence of multifocality in IBTR, to identify patient- and tumor-related predicting factors and to investigate the prognostic significance of multifocality.

METHODS

Two hundred and fifteen patients were included in this analysis. All had an IBTR after BCT and were treated by salvage mastectomy and appropriate adjuvant therapy. Predictive tumor- and patient-related factors for multifocality in IBTR were identified using X2 test and univariate logistic regression analyses. Prognostic outcomes were calculated using Kaplan Meier analysis and compared using the log rank test.

RESULTS

Multifocality was present in 50 (22.9%) of IBTR mastectomy specimens. Axillary positivity in IBTR was significantly associated with multifocality in IBTR. Chest wall re-recurrences occurred more often after multifocal IBTR (14% versus 7% after unifocal IBTR, p = 0.120). Regional re-recurrences did not differ significantly between unifocal and multifocal IBTR (8% vs. 6%, p = 0.773). Distant metastasis after salvage surgery occurred more frequently after multifocal IBTR (15% vs. 24%, p = 0.122). Overall survival was 132 months after unifocal IBTR and 112 months after multifocal IBTR (p = 0.197).

CONCLUSION

The prevalence of multifocality in IBTR is higher than in primary breast cancer. Axillary positivity in IBTR was associated with a multifocal IBTR. Chest wall re-recurrences and distant metastasis were, although not statistically significant, more prevalent after multifocal IBTR.

Influence of neoadjuvant chemotherapy on diffuse reflectance spectra of tissue in breast surgery specimens

Diffuse reflectance spectroscopy (DRS) can discriminate different tissue types based on optical characteristics. Since this technology has the ability to detect tumor tissue, several groups have proposed to use DRS for margin assessment during breast-conserving surgery for breast cancer. Nowadays, an increasing number of patients with breast cancer are being treated by neoadjuvant chemotherapy. Limited research has been published on the influence of neoadjuvant chemotherapy on the optical characteristics of the tissue. Hence, it is unclear whether margin assessment based on DRS is feasible in this specific group of patients. We investigate whether there is an effect of neoadjuvant chemotherapy on optical measurements of breast tissue. To this end, DRS measurements were performed on 92 ex-vivo breast specimens from 92 patients, treated with neoadjuvant chemotherapy and without neoadjuvant chemotherapy. Generalized estimating equation (GEE) models were generated, comparing the measurements of patients with and without neoadjuvant chemotherapy in datasets of different tissue types using a significance level of 5%. As input for the GEE models, either the intensity at a specific wavelength or a fit parameter, derived from the spectrum, was used. In the evaluation of the intensity, no influence of neoadjuvant chemotherapy was found, since none of the wavelengths were significantly different between the measurements with and the measurements without neoadjuvant chemotherapy in any of the datasets. These results were confirmed by the analysis of the fit parameters, which showed a significant difference for the amount of collagen in only one dataset. All other fit parameters were not significant for any of the datasets. These findings may indicate that assessment of the resection margin with DRS is also feasible in the growing population of breast cancer patients who receive neoadjuvant chemotherapy. However, it is possible that we did not detect neoadjuvant chemotherapy effect in the some of the datasets due to the small number of measurements in those datasets.

Feasibility of radioguided occult lesion localization of clip-marked lymph nodes for tailored axillary treatment in breast cancer patients treated with neoadjuvant systemic therapy

Background

Selective removal of initially tumor-positive axillary lymph nodes in breast cancer patients who underwent neoadjuvant systemic treatment (NST) improves the accuracy of nodal staging and provides the opportunity for more tailored axillary treatment. This study evaluated whether radioguided occult lesion localization (ROLL) of clip-marked lymph nodes is feasible in clinical practice.

Methods

Prior to NST, a clip marker was placed inside a proven tumor-positive lymph node in all breast cancer patients (cTis-4N1-3 M0). After NST, technetium-99m-labeled macroaggregated albumin was injected in the clip-marked lymph nodes. The next day, these ROLL-marked nodes were selectively removed at surgery to evaluate the pathological response of the axilla.

Results

Thirty-seven patients (38 axillae) underwent clip insertion. After NST, the clip was visible by ultrasound in 36 procedures (95%). In the other two patients, the ROLL-node injection was performed in a sonographically suspicious unclipped node (1), and near the clip under computed tomography guidance (1). Initial surgery successfully identified the ROLL-marked node with clip in 33 procedures (87%). Removed specimens in the other five procedures contained only the sonographically suspicious tumor-positive unclipped node (1), a node with signs of complete response but no clip (2), a clip without node (1), and tissue without node nor clip, and a second successful ROLL-node procedure was performed (1). Overall, 10 ROLL-marked nodes had no residual disease.

Conclusions

This study demonstrates that the ROLL procedure to identify clip-marked lymph nodes is feasible. This facilitates selective removal at surgery and may tailor axillary treatment in patients treated with NST.

Feasibility of Micro-Computed Tomography Imaging for Direct Assessment of Surgical Resection Margins During Breast-Conserving Surgery

BACKGROUND

To analyze the feasibility and accuracy of micro-computed tomography (micro-CT) for surgical margin assessment in breast excision specimen.

MATERIALS AND METHODS

Two data sets of 30 micro-CT scans were retrospectively evaluated for positive resection margins by four observers in two phases, using pathology as a gold standard. Results of phase 1 were evaluated to define micro-CT evaluation guidelines for phase 2. Interobserver agreement was also assessed (kappa). In addition, a prospective study was conducted in which 40 micro-CT scans were directly acquired, reconstructed, and evaluated for positive resection margins by one observer. A suspect positive resection margin on micro-CT was annotated onto the specimen with ink, enabling local validation by pathology. Main outcome measures were accuracy, sensitivity, specificity, and positive predictive value (PPV).

RESULTS

Average accuracy, sensitivity, specificity, and PPV for the four observers were 63%, 38%, 70%, and 22%, respectively, in phase 1 and 72%, 40%, 78%, and 26%, respectively, in phase 2. The interobserver agreement was fair [kappa (range), 0.31 (0.12-0.80) in phase 1 and 0.23 (0-0.43) in phase 2]. In the prospective study 70% of the surgical resection margins were correctly evaluated. Ten specimens were annotated for positive resection margins, which correlated with three positive and three close (<1 mm) margins on pathology. Sensitivity, specificity, and PPV were 38%, 78%, and 30%, respectively.

CONCLUSIONS

Micro-CT imaging of breast excision specimen has moderate accuracy and considerable interobserver variation for analysis of surgical resection margins. Especially sensitivity and PPV need to be improved before micro-CT-based margin assessment can be introduced in clinical practice.

Internal Mammary Chain Sentinel Nodes in Early-Stage Breast Cancer Patients: Toward Selective Removal

BACKGROUND

Removal of internal mammary chain sentinel nodes (IMCSNs) affects prognosis and treatment of breast cancer, and internal mammary chain radiotherapy (IMCRT) can improve survival for selected patients. This study aimed to determine the effect of IMCSN biopsy on recurrence-free survival (RFS) and overall survival (OS) and to identify predictive factors for IMCSN and distant metastasis.

METHODS

Patients with IMCSNs were selected from a prospective database for the period 1999-2007. Lymphoscintigraphy was performed after intratumoral technetium-99 m injection, and all sentinel nodes were removed. Both RFS and OS were calculated for subgroups with tumor-positive, tumor-negative, or non-removed IMCSNs. Predictive factors were identified for tumor-positive IMCSNs and distant metastasis by regression analysis.

RESULTS

For 287 (85%) of 336 patients, IMCSN biopsy was performed, and metastasis was detected in 38 patients (13%). The patients with tumor-positive IMCSNs had poorer OS than the patients with no IMCSN metastasis or non-removed IMCSNs (p = 0.002). These patients also had worse RFS due to distant metastasis (p = 0.002). Axillary metastasis was predictive for tumor-positive IMCSNs (positive predictive value, 38.5%). The predictive factors for distant metastasis were tumor-positive IMCSNs (hazard ratio [HR], 2.5), non-removed IMCSNs (HR, 2.3), tumor diameter greater than 1.5 cm (HR, 3.5), and age older than 65 years (HR, 3.1; reference, < 50 years).

CONCLUSIONS

Patients with IMCSNs have worse survival due to distant metastasis. The clinically relevant predictive factor for distant metastasis is tumor larger than 1.5 cm. According to the authors' current protocol, IMCSN biopsy is performed for patients younger than 70 years who have a tumor larger than 1.5 cm, with the cardiotoxicity of the adjuvant IMCRT weighed against the survival benefit.

Breast conserving therapy after neoadjuvant chemotherapy; data from the Dutch Breast Cancer Audit

INTRODUCTION

NAC has led to an increase in breast conserving surgery (BCS) worldwide. This study aims to analyse trends in the use of neoadjuvant chemotherapy (NAC) and the impact on surgical outcomes.

METHODS

We reviewed all records of cT1-4N0-3M0 breast cancer patients diagnosed between July 2011 and June 2016 who have been registered in the Dutch National Breast Cancer Audit (NBCA) (N = 57.177). The surgical outcomes of 'BCS after NAC' were compared with 'primary BCS', using a multivariable logistic regression model.

RESULTS

Between 2011 and 2016, the use of NAC increased from 9% to 18% and 'BCS after NAC' (N = 4170) increased from 43% to 57%. We observed an involved invasive margin rate (IMR) of 6,7% and a re-excision rate of 6,6%. As compared to 'primary BCS', the IMR of 'BCS after NAC' is higher for cT1 (12,3% versus 8,3%; p < 0.005), equal for cT2 (14% versus 14%; p = 0.046) and lower for cT3 breast cancer (28,3% versus 31%; p < 0.005). Prognostic factors associated with IMR for both 'primary BCS' as for 'BCS after NAC' are: lobular invasive breast cancer and a hormone receptor positive receptor status (all p < 0,005).

CONCLUSION

The use of NAC and the incidence of 'BCS after NAC' increased exponentially in time for all stages of invasive breast cancer in the Netherlands. This nationwide data confirms that 'BCS after NAC' compared to 'primary BCS' leads to equal surgical outcomes for cT2 and improved surgical outcomes for cT3 breast cancer. These promising results encourage current developments towards de-escalation of surgical treatment.

Tumor Resection Margin Definitions in Breast-Conserving Surgery: Systematic Review and Meta-analysis of the Current Literature

Worldwide, various guidelines recommend what constitutes an adequate margin of excision for invasive breast cancer or for ductal carcinoma-in-situ (DCIS). We evaluated the use of different tumor resection margin guidelines and investigated their impact on positive margin rates (PMR) and reoperation rates (RR). Thirteen guidelines reporting on the extent of a positive margin were reviewed along with 31 studies, published between 2011 and 2016, reporting on a well-defined PMR. Studies were categorized according to the margin definition. Pooled PMR and RR were determined with random-effect models. For invasive breast cancer, most guidelines recommend a positive margin of tumor on ink. However, definitions of reported positive margins in the clinic vary from more than focally positive to the presence of tumor cells within 3 to 5 mm from the resection surface. Within the studies analyzed (59,979 patients), pooled PMRs for invasive breast cancer ranged from 9% to 36% and pooled RRs from 77% to 99%. For DCIS, guidelines vary between no DCIS on the resection surface to DCIS cells found within a distance of 2 mm from the resection edge. Pooled PMRs for DCIS varied from 4% to 23% (840 patients). Given the differences in tumor margin definition between countries worldwide, quality control data expressed as PMR or RR should be interpreted with caution. Furthermore, the overall definition for positive resection margins for both invasive disease and DCIS seems to have become more liberal.

Nonoperative Management for Invasive Breast Cancer After Neoadjuvant Systemic Therapy: Conceptual Basis and Fundamental International Feasibility Clinical Trials

With current advances in neoadjuvant systemic therapy (NST) and improved breast imaging, the potential of nonoperative therapy for invasive breast cancer has emerged as a viable option when utilizing meticulous image-guided percutaneous biopsy to document pathologic complete response. Feasibility clinical trials utilizing this approach are being performed by teams of investigators from single and multicenter/cooperative groups around the world. Imaging alone after NST lacks sufficient sensitivity and specificity in predicting pCR and therefore cannot be utilized for clinical selection of patients for omission of surgery. Imaging with adequate sampling after NST of the residual lesions (or around the remaining clip if a complete radiologic response occurs) appears to be essential in selecting patients with pCR to lower the false-negative rates based on initial reported feasibility studies to identify pCR without surgery that range from 5 to 49%. In this manuscript, recently completed, ongoing, and planned clinical feasibility trials and a new omission of surgery trial are described. Drastic rethinking of all diagnostic and therapeutic management strategies that are ordinarily utilized for patients who receive standard breast cancer surgery is required. A roadmap of essential questions and issues that will have to be resolved as the field of nonoperative breast cancer management advances is described in detail.

Trastuzumab in combination with weekly paclitaxel and carboplatin as neo-adjuvant treatment for HER2-positive breast cancer: The TRAIN-study

AIM

To determine the efficacy and safety of an anthracycline-free neo-adjuvant regimen consisting of weekly paclitaxel, carboplatin and trastuzumab in HER2-positive breast cancer.

PATIENTS AND METHODS

Patients with stage II or III HER2-positive breast cancer received weekly paclitaxel ([P], 70 mg/m²), trastuzumab ([T], 2 mg/kg, loading dose 4 mg/kg) and carboplatin ([C], AUC = 3 mg ml^-1 min) for 24 weeks. In weeks 7, 8, 15, 16, 23 and 24, trastuzumab was administered without chemotherapy. The primary end-point was pathologic complete response in the surgical resection specimen, defined as the absence of invasive tumour cells in breast and axilla.

RESULTS

One hundred and eleven patients were included in the study, and 108 were evaluable for the primary end-point. The pathologic complete response rate was 43% (95% confidence interval [CI]: 33-52). Median follow-up was 52 months, and the 3-year event-free survival was 88% (95% CI: 82-94), and the 3-year overall survival was 92% (95% CI: 88-98). The most common grade 3-4 adverse events were neutropenia (67%) and thrombocytopenia (43%). Less than five percent of patients experienced febrile neutropenia. No symptomatic left ventricular systolic dysfunction was observed during neo-adjuvant treatment.

CONCLUSION

An anthracycline-free neo-adjuvant regimen of weekly paclitaxel, trastuzumab and carboplatin is highly effective in HER2-positive breast cancer with manageable toxicity.

Survival is associated with complete response on MRI after neoadjuvant chemotherapy in ER-positive HER2-negative breast cancer

Background

Pathological complete remission (pCR) of estrogen receptor (ER)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer is rarely achieved after neoadjuvant chemotherapy (NAC). In addition, the prognostic value of pCR for this breast cancer subtype is limited. We explored whether response evaluation by magnetic resonance imaging (MRI) is associated with recurrence-free survival after NAC in ER-positive/HER2-negative breast cancer.

Methods

MRI examinations were performed in 272 women with ER-positive/HER2-negative breast cancer before, during and after NAC. MRI interpretation included lesion morphology at baseline, changes in morphology and size, and contrast uptake kinetics. These MRI features, clinical characteristics and final pathology were correlated with recurrence-free survival.

Results

The median follow up time was 41 months. There were 35 women with events, including 19 breast-cancer-related deaths. On multivariable analysis, age younger than 50 years (hazard ratio (HR) = 2.55, 95 % confidence interval (CI) 1.3, 5.02, p = 0.007), radiological complete response after NAC (HR = 14.11, CI 1.81, 1818; p = 0.006) and smaller diameters of washout/plateau enhancement at MRI after NAC (HR = 1.02, CI 1.00, 1.04, p = 0.036) were independently associated with best recurrence-free survival. Pathological response was not significant; HR = 2.12, CI 0.86, 4.64, p = 0.096.

Conclusions

MRI after NAC in ER-positive/HER2-negative tumors may be predictive of recurrence-free survival. A radiological complete response at MRI after NAC is associated with an excellent prognosis.

Heading toward radioactive seed localization in non-palpable breast cancer surgery? A meta-analysis

Wire-guided localization is the most commonly used technique for intraoperative localization of non-palpable breast cancer. Radioactive seed localization (RSL) is becoming more popular and seems to be a reliable alternative for intraoperative lesion localization. The purpose of the present meta-analysis was to evaluate the use of RSL. Primary study outcomes were irradicality and re-excision rates. In total 3168 patients were included. The clinical adaptation shows growing confidence in RSL and further growth is expected.

Accuracy of 18F-FDG PET/CT for primary tumor visualization and staging in T1 breast cancer

BACKGROUND

The aim of this study was to assess the accuracy of 18F-FDG PET/CT in T1 breast cancer regarding visualization of the primary tumor and the detection of locoregional and distant metastases.

METHODS

Sixty-two women with invasive T1 breast cancer underwent a PET/CT. Image acquisition of the thorax was done in prone position with hanging breasts, followed by whole-body scanning in supine position. Primary tumor FDG uptake was evaluated and compared with clinical and histopathological characteristics. Presence of locoregional and distant metastases was assessed and compared with conventional imaging procedures.

RESULTS

The primary tumor was visible with PET/CT in 54 (87%) of 62 patients, increasing from 59% (10/17) in tumors ≤ 10 mm to 98% (44/45) in tumors over 10 mm. All triple negative and HER2-positive tumors and 40/48 (83%) ER-positive/HER2-negative tumors were visualized. Sensitivity and specificity of PET/CT in the detection of axillary metastases were 73% and 100%, respectively. PET/CT depicted periclavicular nodes in two patients. Of 12 distant lesions, one was confirmed to be a lung metastasis, three were false positive, and eight were new primary proliferative lesions.

CONCLUSION

Using optimal imaging acquisition, the majority of T1 breast carcinomas can be visualized with PET/CT. Specificity in the detection of axillary metastases is excellent, but sensitivity appears to be limited. Additional whole body imaging has a low yield in this specific patient group.