Impact of age on indication for chemotherapy in early breast cancer patients: results from 104 German institutions from 2008 to 2017.

PURPOSE: Today, the decision to treat patients with chemotherapy for early breast cancer (EBC) is made based on the patient's individual risk stratification and tumor biology. In cases with chemotherapy indication, the neoadjuvant application (NACT) is the preferred option in comparison with primary surgery and adjuvant chemotherapy (ACT). Age remains a relevant factor in the decision-making process. The aim of the present study was to illustrate the impact of age on the use of systemic therapy in clinical routine. METHODS: The study separately analyzed chemotherapy use among six age cohorts of EBC patients who had been treated at 104 German breast units between January 2008 and December 2017. RESULTS: In total, 124,084 patients were included, 46,279 (37.3%) of whom had received chemotherapy. For 44,765 of these cases, detailed information on treatment was available. Within this cohort, chemotherapy was administered as NACT to 14,783 patients (33.0%) and as ACT to 29,982 (67.0%) patients. Due to the higher prevalence of unfavorable tumor subtypes, younger patients had a higher rate of chemotherapy (≤ 29y: 74.2%; 30-39y: 71.3%) and a higher proportion of NACT administration ( ≤ 29y: 66.9%; 30-39y: 56.0%) in comparison with elderly patients, who had lower rates for overall chemotherapy (60-69y: 37.5%; ≥ 70y: 17.6%) and NACT (60-69y: 25.5%; ≥ 70y: 22.8%). Pathologic complete response was higher in younger than in older patients (≤ 29y: 30.4% vs. ≥ 70y: 16.7%), especially for HER2- subtypes. CONCLUSION: The data from the nationwide German cohort reveal relevant age-dependent discrepancies concerning the use of chemotherapy for EBC.

Do hospital type or caseload make a difference in chemotherapy treatment patterns for early breast cancer? Results from 104 German institutions, 2008-2017.

BACKGROUND: Over the past decade, chemotherapy has been used more selectively in early breast cancer (EBC) due to better risk stratification. Neoadjuvant chemotherapy (NACT) has evolved to the primary treatment option. The type and size of hospitals is known to have a substantial influence on the kinds of treatment they provide, and therefore on patient outcomes (e.g. rates for pathological complete response, pCR), but it is not yet known how this has affected delivery of chemotherapy for EBC in Germany. METHODS: This study analyzed chemotherapy use and pCR rates after NACT for EBC patients treated at 104 German institutions 2008-2017. Institutions were separated into associated hospital type (university hospital; teaching hospital; community hospital) and annual caseload (≤100; 101-250; >250 cases/year). RESULTS: Overall, 124,084 patients were included, of whom 11.6% were treated at university hospitals, 63.1% at teaching hospitals, and 25.3% at community hospitals. In total, 46,274 (37.3%) received chemotherapy, of whom 44,765 had information available about systemic treatment and surgery. From 2008 to 2017, chemotherapy use declined from 48.3% to 36.4% for university hospitals, from 40.7% to 30.3% for teaching hospitals, and from 42.4% to 33.7% for community hospitals. Furthermore, the proportion of NACT increased the most in university hospitals (from 32.0% to 68.1%); whereas, the rate of pCR (defined as ypT0 ypN0) increased irrespective of institutional type. Analyses regarding annual caseload did not show any differences. CONCLUSIONS: The results from this large, nationwide cohort reflect a more selective use of chemotherapy in Germany, irrespective of institutional type or case load.

Analyzing non-sentinel axillary metastases in patients with T3-T4 cN0 early breast cancer and tumor-involved sentinel lymph nodes undergoing breast-conserving therapy or mastectomy.

PURPOSE: In the ACOSOG Z0011 trial, completing axillary lymph node dissection (cALND) did not benefit patients with T1-T2 cN0 early breast cancer and 1-2 positive sentinel lymph nodes (SLN) undergoing breast-conserving surgery (BCT). This paper reports cALND rates in the clinical routine for patients who had higher (T3-T4) tumor stages and/or underwent mastectomy but otherwise met the ACOSOG Z0011 eligibility criteria. Aim of this study is to determine cALND time trends and non-sentinel axillary metastases (NSAM) rates to estimate occult axillary tumor burden. METHODS: Data were included from patients treated in 179 German breast cancer centers between 2008 and 2015. Time-trend rates were analyzed for cALND of patients with T3-T4 tumors separated for BCT and mastectomy and regarding presence of axillary macrometastases or micrometastases. RESULTS: Data were available for 188,909 patients, of whom 19,009 were identified with 1-2 positive SLN. Those 19,009 patients were separated into 4 cohorts: (1) Patients with T1-T2 tumors receiving BCT (ACOSOG Z0011 eligible; n = 13,741), (2) T1-T2 with mastectomy (n = 4093), (3) T3-T4 with BCT (n = 269), (4) T3-T4 with mastectomy (n = 906). Among patients with T3-T4 tumors, cALND rates declined from 2008 to 2015: from 88.2 to 62.6% for patients receiving mastectomy and from 96.6 to 58.1% in patients receiving BCT. Overall rates for any NSAM after cALND for cohorts 1-4 were 33.4%, 42.3%, 46.9%, 58.8%, respectively. CONCLUSIONS: The cALND rates have decreased substantially in routine care in patients with 'extended' ACOSOG Z0011 eligibility criteria. Axillary tumor burden is higher in these patients than in the ACOSOG Z0011 trial.

Time trends of neoadjuvant chemotherapy for early breast cancer.

Neoadjuvant chemotherapy (NACT) in early breast cancer (EBC) enables in vivo sensitivity testing and less radical surgery as compared to primary surgery and adjuvant chemotherapy (ACT). The aim of our study is to illustrate trends of systemic treatment of EBC. The study analyzed chemotherapy usage and time trends for patients with EBC treated at 104 German breast units between January 2008 and December 2017. The data were obtained through a quality-controlled benchmarking process. Altogether, 124 084 patients were included, of whom 46 279 (37.3%) received chemotherapy. For 44 765 of these cases, detailed information on systemic treatment and surgery were available. Overall use of chemotherapy declined from 42.0% in 2008 to 32.0% in 2017. During that same time, the proportion of NACT increased from 20.0% to 57.7%, irrespective of tumor subtype. The pathological complete response (pCR) rate (defined as ypT0 ypN0) at surgery after NACT increased from 15.0% to 34.2%. The results from this large cohort from the clinical routine reflect the refined indications for chemotherapy in EBC.

Non-sentinel axillary tumor burden applying the ACOSOG Z0011 eligibility criteria to a large routine cohort.

PURPOSE: In the ACOSOG Z0011 trial, patients with primary breast cancer (BC) and 1-2 tumor-involved sentinel lymph nodes (SLN) undergoing breast-conserving surgery gained no benefit from completing axillary lymph node dissection (cALND). This paper reports cALND rates performed in clinical routine on patients who would meet the Z0011 criteria. Further, patients still received cALND were analyzed concerning the number of non-sentinel metastases (NSM) to estimate occult axillary tumor burden. METHODS: Data were retrospectively analyzed from patients treated in 179 German breast centers between 2008 and 2015. Time-trend rates were determined for cALND regarding the presence of axillary macrometastases or micrometastases. Descriptive statistics were used to report the number of NSM depending on the number of SLN removed, tumor-involved SLN, tumor stage (pT1-2), and immunohistochemical subtype. Factors associated with NSM were identified using multivariable logistic regression. RESULTS: Altogether, data for 188,909 patients were available, of whom 13,741 (7.3%) were identified eligible for the Z0011 criteria. For these patients, the cALND rate for macrometastases declined from 96.4% in 2008 to 49.7% in 2015, for micrometastases from 86.7 to 5.9%. In total 9773 patients still received cALND, 33.4% of whom had NSM. The NSM rates were: 38.8% for pN(1/1sn), 28.6% for pN(1/2sn), and 50.9% for pN(2/2sn). Hormone receptor (HR) positive/HER2+ showed the highest NSM rate (41.6%), HR-/HER2- the lowest rate (29.4%). CONCLUSIONS: The rate of cALND for ACOSOG Z0011 eligible patients has decreased substantially in routine care in our nationwide cohort. Our data reveal a relatively high prevalence of additional axillary NSM tumor burden.

Evolution of the Use of Completion Axillary Lymph Node Dissection in Patients with T1/2N0M0 Breast Cancer and Tumour-Involved Sentinel Lymph Nodes Undergoing Mastectomy: A Cohort Study.

BACKGROUND: In breast cancer, completion axillary lymph node dissection (cALND) was previously recommended for patients with at least one tumour-affected sentinel lymph node (SLN). Several prospective trials predominantly in patients undergoing breast-conserving surgery showed no benefit and increased arm morbidity with this procedure. We report the influence of these trials on clinical practice of patients undergoing mastectomy. METHODS: We analysed prospectively collected data from patients with primary invasive breast cancer treated at German breast cancer units between January 2008 and December 2015. Time trends of cALND rates were analysed in patients undergoing mastectomy for T1/2N0M0 breast cancer with one or two tumour-involved SLNs. Multivariable logistic regression was used to determine factors influencing the decision not to perform cALND. RESULTS: Among the entire study cohort of 166,074 patients treated at 179 breast cancer units, 4093 patients (2%) had T1/2N0M0 breast cancer with one or two tumour-involved SLNs and underwent mastectomy. cALND rates decreased from 89.9% in 2010 to 55.5% in 2015 (p < 0.001). Rates decreased from 82% to 8% in patients with micrometastatic SLN disease and from 93% to 63% in those with macrometastasis (p < 0.001). In multivariable analysis, factors associated with omission of cALND were treatment at a general, nonacademic hospital, pT1 status, older age, higher number of removed SLNs, fewer tumour-affected SLNs, and SLN micrometastasis (all p < 0.001). CONCLUSIONS: Despite limited evidence from prospective trials relating to the omission of cALND specifically in patients undergoing mastectomy, our nationwide data show that use of cALND decreased in these patients in routine clinical practice.

Which patients with sentinel node-positive breast cancer after breast conservation still receive completion axillary lymph node dissection in routine clinical practice?

PURPOSE: In the American College of Surgeons Oncology Group (ACOSOG) Z0011 trial, patients with 1 or 2 tumour-involved sentinel lymph nodes (SLNs) gained no benefit from completion axillary lymph dissection (cALND). We examined implementation of evidence from this trial into routine clinical management. METHODS: Data were included from patients diagnosed with primary breast cancer in German breast cancer units between 2008 and 2015 and analysed retrospectively from a prospective maintained database. Descriptive analyses assessed time-trend changes in axillary surgery. Factors associated with cALND in patients with 1 or 2 positive SLNs were identified using multivariable logistic regression analysis. RESULTS: Overall, 179 breast cancer units provided data for 188,909 patients, of whom 13,741 (7.3%) had pT1/2cN0M0 invasive breast cancer with 1 or 2 tumour-involved SLNs and underwent breast-conserving surgery and adjuvant radiotherapy. cALND use decreased from 94.6% in 2008 to 46.9% in 2015 (p < 0.001). In multivariable analyses, the following factors were associated with cALND: fewer removed SLNs; two tumour-affected SLNs; younger age; lower annual case volume per hospital; higher tumour grade and lymphovascular invasion. No statistically significant influence was detected for hormone receptor or HER2 status. CONCLUSION: In our cohort, 7.3% of patients with primary breast cancer met the ACOSOG Z0011 inclusion criteria and could potentially have been spared the morbidity of cALND. cALND tended to be performed in patients with a higher axillary tumour burden. This study shows a shift towards less extensive axillary surgery through rapid implementation of new clinical trial evidence into routine clinical practice.