Use of 21-gene recurrence score assay to individualize adjuvant chemotherapy recommendations in ER+/HER2- node positive breast cancer-A National Cancer Database study

The 21-gene Recurrence Score (RS) assay is prognostic and predictive of adjuvant chemotherapy benefit in node positive (N+) breast cancer (BC). We sought to evaluate use patterns of RS assay in N+, ER+/HER2- BC and the impact of RS on recommendations for adjuvant chemotherapy. Patients with T1-T4c,N1mi-N3, ER+/HER2- BC diagnosed 2010-2013 in the National Cancer Database were analyzed. Multivariable logistic regression assessed factors influencing RS testing and chemotherapy recommendations based on RS. Among 72,897 patients, RS was obtained in 20.6%, increasing from 15.0% in 2010 to 24.5% in 2013 (p < 0.001). RS testing was most common in N1mi (43.7%) followed by N1 (22.1%) and rare in N2/N3 (3.3%). Of the 12,536 with quantitative RS results, 61.1% were low RS, 32.3% intermediate RS and 6.6% high RS. Chemotherapy was recommended less frequently in patients with RS testing (50.4%) vs. those not tested (81.0%, p < 0.001). In N1mi/N1 patients, chemotherapy recommendation varied by RS; however, in N2/N3 patients, chemotherapy was recommended in the majority (70.9-87.5%) regardless of RS. Most patients (>85%) with RS ≥ 26 were recommended chemotherapy regardless of nodal stage. For patients with RS < 26, chemotherapy recommendations increased with higher N and T stage, grade, and younger age (p < 0.001). Histology was not associated with chemotherapy recommendation in any RS subset. The RS assay is frequently and increasingly being used for decision making in node positive ER+/HER2- breast cancer patients and its use is associated with lower rates of adjuvant chemotherapy.

Selective Use of Sentinel Lymph Node Surgery in Patients Undergoing Prophylactic Mastectomy Using Intraoperative Pathology

BACKGROUND

Routine sentinel lymph node (SLN) surgery during prophylactic mastectomy (PM) is unnecessary, because most PMs do not contain cancer. Our institution utilizes intraoperative pathology to guide the surgical decision for resection of SLNs in PM. The purpose of this study was to review the effectiveness of this approach.

METHODS

We identified all women aged ≥18 years who underwent bilateral PM (BPM) or contralateral PM (CPM) at our institution from January 2008 to July 2016. We evaluated the frequency of SLN resection and rate of occult breast cancer (DCIS or invasive disease) in the PM. We used the following definitions: over-treatment-SLN surgery in patients without cancer; under-treatment-no SLN surgery in patients with cancer; appropriate treatment-no SLN in patients without cancer or SLN surgery in patients with cancer.

RESULTS

PM was performed on 1900 breasts: 1410 (74.2%) CPMs and 490 (25.8%) BPMs. Cancer was identified in 58 (3.0%) cases (32 invasive disease and 26 DCIS) and concurrent SLN surgery was performed in 44 (75.9%) of those cases. Overall, SLN surgery guided by intraoperative pathology resulted in appropriate treatment of 1787 (94.1%) cases: 1319 (93.5%) CPMs and 468 (95.5%) BPMs, by avoiding SLN in 1743/1842 cases without cancer (94.6%), and performing SLN surgery in 44/58 cases with cancer (75.9%).

CONCLUSIONS

Use of intraoperative pathology to direct SLN surgery in patients undergoing PM minimizes over-treatment from routine SLN in PM and minimizes under-treatment from avoiding SLN in PM, demonstrating the value of intraoperative pathology in this era of focus on appropriateness of care.

Contralateral Prophylactic Mastectomy with Immediate Breast Reconstruction Increases Healthcare Utilization and Cost

BACKGROUND

The rates of contralateral prophylactic mastectomy (CPM) in women with unilateral breast cancer continue to rise, especially in women undergoing immediate breast reconstruction (IBR).

METHODS

We utilized administrative claims data from a large US commercial insurance database (OptumLabs) to identify women age 18-64 years who underwent IBR between January 2004 and December 2013. We compared 2-year unadjusted utilization rates and total costs of care between unilateral mastectomy (UM) and bilateral mastectomy (BM) for implant-based and autologous reconstruction. Comparisons were tested using t-test and differences in cost were estimated using the Wilcoxon rank-sum test.

RESULTS

Overall, 11,235 women undergoing mastectomy with IBR were identified; 7319 with implant reconstruction [1923 UM (26%) and 5396 BM (74%)] and 3916 with autologous reconstruction [1687 UM (43%) and 2229 BM (57%)]. The overall rate of office visits (2386 vs. 2391 per 100 women, p = 0.42) and hospital readmission rate (29.1 per 100 women vs. 27.4, p = 0.06) were similar between BM + IBR and UM + IBR. Women undergoing BM + IBR had a higher emergency room (ER) visit rate (34.1 per 100 women vs. 29.8, p < 0.0001). The total 2-year cost of care was higher for BM + IBR than UM + IBR for implant reconstruction ($106,711 vs. $97,218, p < 0.0001) and for autologous reconstruction ($114,725 vs. $87,874, p < 0.0001).

CONCLUSIONS

BM + IBR (autologous or implant) was associated with increased ER visits and higher total cost of care over 2 years compared with UM + IBR. Patients considering CPM should be counseled on the additional risks and costs associated with BM + IBR.

Predicting Nodal Positivity in Women 70 Years of Age and Older with Hormone Receptor-Positive Breast Cancer to Aid Incorporation of a Society of Surgical Oncology Choosing Wisely Guideline into Clinical Practice

PURPOSE

One of the Society of Surgical Oncology Choosing Wisely guidelines recommends avoiding routine sentinel lymph node (SLN) surgery in clinically node-negative women ≥70 years of age with hormone receptor-positive (HR+) breast cancer. We sought to assess the impact of tumor stage and grade on nodal positivity, and to develop a model to identify patients at low-risk of nodal positivity to aid adoption of the guideline.

METHODS

We identified women ≥70 years of age with HR+ cN0 invasive breast cancer in the National Cancer Database (NCDB; 2010-2013) and examined the impact of tumor stage and grade on nodal positivity to identify low-risk combinations. A multivariable logistic regression model was developed to incorporate additional factors. The area under the curve (AUC) and relative risks (RR) were used to assess performance.

RESULTS

Among 71,834 cases, the pathologic nodal positivity (pN+) rate was 15.3%. We identified low-risk criteria as grade 1, cT1mi-T1c (≤2.0 cm), or grade 2, cT1mi-T1b (≤1.0 cm), with pN+ rates of 7.8% compared with 22.3% in patients not meeting these criteria (RR 2.86, p < 0.001). On multivariable analysis, factors associated with pN+ status included clinical T stage, grade, and histology (each p < 0.001). The resulting model had AUC 0.70 and identified women with low predicted probability (<10%) of positive nodes, of whom 6.3% were pN+, versus 21.2% in those with predicted probability ≥10% (RR 3.34, p < 0.001).

CONCLUSION

The simple clinical rule (grade 1, cT1mi-T1c, or grade 2, cT1mi-T1b), as well as the predictive model, both identify women at low risk of nodal positivity where SLN surgery can be omitted.

Clinical Decision-Making in Patients with Variant of Uncertain Significance in BRCA1 or BRCA2 Genes

BACKGROUND

How diagnosis with a variant of uncertain significance (VUS) in a BRCA gene impacts clinical decision-making is not well known.

METHODS

We queried for all patients attending Mayo Clinic Rochester from 2004 to 2016 who tested positive for BRCA1 or BRCA2 VUS and reviewed patient management choices. Groups were compared by using Wilcoxon rank-sum and Chi-square tests.

RESULTS

We identified 97 patients (95 females, 2 males) with BRCA VUS. For patients without cancer history (n = 20), 80% had a mother or sister with breast cancer, and median Tyrer-Cuzick (IBIS) lifetime breast cancer risk score was 27% (range 16-62%). Management included bilateral prophylactic mastectomy (BPM) in 39%, where choice for BPM was significantly associated with IBIS score (median 32 vs. 24%, p = 0.02) and first-degree family history of breast cancer (100 vs. 64%, p = 0.03) but not Gail score or total number of family members with cancer. For patients with breast cancer who had known VUS status prior to surgery (n = 9), the rate of contralateral prophylactic mastectomy (CPM) was 22% compared with 25% without known VUS and 83% with known BRCA pathogenic mutation. In 21 of 97 (22%) patients, the BRCA VUS has been reclassified (95% benign, 5% deleterious).

CONCLUSIONS

BRCA VUS carriers with cancer elected surgical choices similar to average-risk breast cancer patients. However, VUS carriers without cancer had high rates of BPM, associated with first-degree family history and IBIS score. Over time, a significant proportion of BRCA VUS were reclassified, illustrating the importance of appropriate counseling regarding VUS.

Localizing the Clipped Node in Patients with Node-Positive Breast Cancer Treated with Neoadjuvant Chemotherapy: Early Learning Experience and Challenges

BACKGROUND

Placement of a clip in the positive node in patients presenting with node-positive breast cancer treated with neoadjuvant chemotherapy (NAC) allows resection of the clipped node at SLN surgery and improves the accuracy of surgical staging. We sought to evaluate our experience with SLN surgery with resection of the clipped node since incorporation into our practice.

METHODS

With Institutional Review Board approval, we evaluated all breast cancer patients with a percutaneous biopsy-positive axillary lymph node, clipped at the time of diagnosis, who underwent NAC followed by surgery.

RESULTS

Fifty-six node-positive patients were identified. Eighteen patients (32.1%) underwent axillary dissection without sentinel lymph node (SLN) surgery, and 38 patients underwent SLN surgery (18 patients underwent SLN surgery alone, and 20 patients underwent SLN surgery and axillary lymph node dissection). In 25 patients, preoperative localization of the clipped node with an ¹²⁵I radioactive seed was attempted. This was performed by ultrasound guidance in 18 cases (72%), computed tomography (CT) guidance in two cases (8%), and was unable to be localized in five cases (20%). In all 20 seed-localized cases, the seed and the clipped node were resected along with additional SLNs. In 14 patients without seed localization (nine not attempted, five unable to be localized), the clipped node was resected in 11 cases (79%)-as one of the SLNs (6), by intraoperative ultrasound (4), or by palpation (1). Overall, the clipped node was resected in 31/34 (91%) cases.

CONCLUSION

Preoperative ultrasound localization of the clipped node was successful in 72% of cases. Alternatively, the clipped node can be identified by preoperative CT, routine SLN surgery, intraoperative ultrasound, or palpation.

Breast Cancer-Related Lymphedema Risk is Related to Multidisciplinary Treatment and Not Surgery Alone: Results from a Large Cohort Study

BACKGROUND

Breast cancer-related lymphedema (BCRL) is a significant complication for women undergoing treatment. We assessed BCRL incidence and risk factors in a large population-based cohort.

METHODS

We utilized the Olmsted County Rochester Epidemiology Project Breast Cancer Cohort from 1990-2010 and ascertained BCRL and risk factors. The cumulative incidence estimator was used to estimate the rate of BCRL; competing risks regression was used for multivariable analysis.

RESULTS

A total of 1794 patients with stage 0-3 breast cancer with a median of 10 years follow-up were included. The cumulative incidence of BCRL diagnosis within 5 years was 9.1% [95% confidence interval (CI) 7.8-10.5%]. No BCRL events occurred among patients without axillary surgery. In the axillary surgery subset (n = 1512), the 5-year incidence of BCRL was 5.3% in sentinel lymph node (SLN) surgery and 15.9% in axillary dissection (ALND) patients (p < 0.001). In patients treated with surgery only, BCRL rates were not different between ALND versus SLN (3.5 and 4.1% at 5 years, p = 0.36). Addition of breast or chest wall radiation more than doubled the BCRL rate in ALND patients (3.5 vs. 9.5% at 5 years, p = 0.01). The groups with highest risk (>25% at 5 years) all involved ALND with nodal RT and/or anthracycline/cytoxan + taxane chemotherapy. In multivariable analysis of patients with any axillary surgery factors significantly associated with BCRL were ALND, chemotherapy, radiation, and obesity.

CONCLUSIONS

BCRL is a sequelae of multimodal breast cancer treatment and risk is multifactorial. BCRL rates are higher in patients receiving chemotherapy, radiation, ALND, more advanced disease stage, and higher body mass index.

Tumor Sequencing and Patient-Derived Xenografts in the Neoadjuvant Treatment of Breast Cancer

Background

Breast cancer patients with residual disease after neoadjuvant chemotherapy (NAC) have increased recurrence risk. Molecular characterization, knowledge of NAC response, and simultaneous generation of patient-derived xenografts (PDXs) may accelerate drug development. However, the feasibility of this approach is unknown.

Methods

We conducted a prospective study of 140 breast cancer patients treated with NAC and performed tumor and germline sequencing and generated patient-derived xenografts (PDXs) using core needle biopsies. Chemotherapy response was assessed at surgery.

Results

Recurrent "targetable" alterations were not enriched in patients without pathologic complete response (pCR); however, upregulation of steroid receptor signaling and lower pCR rates (16.7%, 1/6) were observed in triple-negative breast cancer (TNBC) patients with luminal androgen receptor (LAR) vs basal subtypes (60.0%, 21/35). Within TNBC, TP53 mutation frequency (75.6%, 31/41) did not differ comparing basal (74.3%, 26/35) and LAR (83.3%, 5/6); however, TP53 stop-gain mutations were more common in basal (22.9%, 8/35) vs LAR (0.0%, 0/6), which was confirmed in The Cancer Genome Atlas and British Columbia data sets. In luminal B tumors, Ki-67 responses were observed in tumors that harbored mutations conferring endocrine resistance ( p53, AKT, and IKBKE ). PDX take rate (27.4%, 31/113) varied according to tumor subtype, and in a patient with progression on NAC, sequencing data informed drug selection (olaparib) with in vivo antitumor activity observed in the primary and resistant (postchemotherapy) PDXs.

Conclusions

In this study, we demonstrate the feasibility of tumor sequencing and PDX generation in the NAC setting. "Targetable" alterations were not enriched in chemotherapy-resistant tumors; however, prioritization of drug testing based on sequence data may accelerate drug development.

Is axillary surgery beneficial for patients with adenoid cystic carcinoma of the breast?

BACKGROUND AND OBJECTIVES

Adenoid cystic carcinoma (ACC) is a rare, typically triple-negative, breast cancer reported to have a favorable prognosis and low rate of nodal metastasis. No consensus guidelines exist for axillary staging and treatment.

METHODS

We identified all patients with ACC evaluated at our institution from January 1994 to August 2016. Patient, tumor, and treatment variables were abstracted and analyzed.

RESULTS

We identified 20 pure ACCs (0.13% of all invasive breast cancers) with size range 0.2-4.8 cm, in 19 women, median age 59 years. Preoperative axillary ultrasound was normal in 10/13 women and suspicious in 3/13 who had a subsequent negative lymph node fine needle aspiration (FNA). Fifteen patients (75%) had sentinel lymph node surgery and were pathologically node-negative, while the remaining five had no axillary surgery. With 3.6 years median follow-up (range 0.2-38.6 years), three patients experienced an in-breast recurrence at 2, 16, and 17 years, respectively, while none recurred in regional nodes.

CONCLUSIONS

We observed no cases of nodal metastasis in 20 consecutive cases of ACC of the breast. Preoperative axillary ultrasound with FNA of suspicious nodes accurately predicted pathologic nodal stage. These data suggest axillary surgery might be omitted safely in patients with pure ACC and a clinically negative axilla.

ACS CRP Dissemination and Implementation Committee issues call for participants in pilot project

According to HHS, dissemination and implementation research is designed “to bridge the gap between public health, clinical research, and everyday practice by building a knowledge base about how health information, interventions, and new clinical practices and policies are transmitted and translated for public health and health care service use in specific settings".