Creating and Implementing a Principal Investigator Tool Kit for Enhancing Accrual to Late Phase Clinical Trials: Development and Usability Study.

BACKGROUND: Accrual to oncology clinical trials remains a challenge, particularly during the COVID-19 pandemic. For late phase clinical trials funded by the National Cancer Institute, the development of these research protocols is a resource-intensive process; however, mechanisms to optimize patient accrual after trial activation are underdeveloped across the National Clinical Trial Network (NCTN). Low patient accrual can lead to the premature closure of clinical trials and can ultimately delay the availability of new, potentially life-saving therapies in oncology. OBJECTIVE: The purpose of this study is to formally create an easily implemented tool kit of resources for investigators of oncology clinical trials within the NCTN, specifically the NRG Oncology cooperative group, in order to optimize patient accrual. METHODS: NRG Oncology sought to formally develop a tool kit of resources to use at specific time points during the lifetime of NRG Oncology clinical trials. The tools are clearly described and involve the facilitation of engagement of the study principal investigator with the scientific and patient advocate community during the planning, activation, and accrual periods. Social media tools are also leveraged to enhance such engagement. The principal investigator (PI) tool kit was created in 2019 and thereafter piloted with the NRG Oncology/Alliance NRG-LU005 phase II or III trial in small-cell lung cancer. The PI tool kit was developed by the NRG Oncology Protocol Operations Management committee and was tested with the NRG/Alliance LU005 randomized trial within the NCTN. RESULTS: NRG Oncology/Alliance NRG-LU005 has seen robust enrollment, currently 127% of the projected accrual. Importantly, many of the tool kit elements are already being used in ongoing NRG Oncology trials, with 56% of active NRG trials using at least one element of the PI tool kit and all in-development trials offered the resource. This underscores the feasibility and potential benefits of deploying the PI tool kit across all NRG Oncology trials moving forward. CONCLUSIONS: While clinical trial accrual can be challenging, the PI tool kit has been shown to augment accrual in a low-cost and easily implementable fashion. It could be widely and consistently deployed across the NCTN to improve accrual in oncology clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT03811002; https://clinicaltrials.gov/ct2/show/NCT03811002.

Definitive results of a phase III adjuvant trial comparing six cycles of FEC-100 to four cycles of AC in women with operable node-negative breast cancer: the NSABP B-36 trial (NRG Oncology).

PURPOSE: Results from adjuvant trials evaluating 6 cycles of epirubicin-based chemotherapy regimens suggested these programs may be more effective than 4 cycles of doxorubicin-based chemotherapy. METHOD: NSABP B-36 was a phase III clinical trial originally designed as a 2 × 2 factorial study comparing 6 cycles of 5-FU, epirubicin, and cyclophosphamide (FEC-100) to 4 cycles of conventional doxorubicin and cyclophosphamide (AC) with celecoxib or placebo. Shortly after activation, concerns regarding increased cardiovascular risks among selective COX-2 inhibitors resulted in a decision to remove the celecoxib/placebo from the trial. Women with histologically node-negative invasive breast cancer who had undergone primary surgery with a lumpectomy or total mastectomy were eligible. Primary endpoint was disease-free survival (DFS). RESULTS: Between May 2004 and July 2008, 2722 patients were enrolled. Administration of FEC-100 did not result in improvement in DFS compared to AC (HR 1.09; 95% CI 0.92-1.29, p value = 0.31). The effect of FEC-100 compared to AC on DFS was significantly different for receptor-positive (HR 1.32, 95% CI 1.05-1.66) compared to receptor-negative patients (HR 0.86, 95% CI 0.66-1.11) (treatment-by-receptor status interaction p value = 0.02). There was no statistically significant difference in the effect of treatment on overall survival (OS) with FEC-100 compared to AC (HR 1.06; 95% CI 0.84-1.35, p value = 0.61). Overall, Grade 3 and 4 adverse events were more frequent in the FEC-100 group. CONCLUSION: The results of B-36 do not support use of six-cycle anthracycline-based regimens in node-negative breast cancer. Prolongation of anthracycline-based therapy with FEC-100 does not improve DFS or OS, relative to AC for 4 cycles, and was associated with expected increases in toxicity. A statistically significant interaction between treatment and hormone receptor status favoring AC in hormone-receptor-positive breast cancers is consistent with the hypothesis that optimal duration of chemotherapy may be four cycles in these patients. Late cardiac events and deaths prior to recurrence or second cancer were infrequent on both arms, but slightly higher with FEC-100. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00087178.

Early Local Therapy for the Primary Site in De Novo Stage IV Breast Cancer: Results of a Randomized Clinical Trial (EA2108).

PURPOSE: Distant metastases are present in 6% or more of patients with newly diagnosed breast cancer. In this context, locoregional therapy for the intact primary tumor has been hypothesized to improve overall survival (OS), but clinical trials have reported conflicting results. METHODS: Women presenting with metastatic breast cancer and an intact primary tumor received systemic therapy for 4-8 months; if no disease progression occurred, they were randomly assigned to locoregional therapy for the primary site (surgery and radiotherapy per standards for nonmetastatic disease) or continuing sysmetic therapy. The primary end point was OS; locoregional control and quality of life were secondary end points. The trial design provided 85% power to detect a 19.3% absolute difference in the 3-year OS rate in randomly assigned patients. The stratified log-rank test and Cox proportional hazards model were used to compare OS between arms. Cumulative incidence of locoregional progression was compared using Gray's test. Quality-of-life assessment used standard instruments. RESULTS: Of 390 participants enrolled, 256 were randomly assigned: 131 to continued systemic therapy and 125 to early locoregional therapy. The 3-year OS was 67.9% without and 68.4% with early locoregional therapy (hazard ratio = 1.11; 90% CI, 0.82 to 1.52; P = .57). The median OS was 53.1 months (95% CI, 47.9 to not estimable) in the systemic therapy arm and 54.9 months (95% CI, 46.7 to not estimable) in the locoregional therapy arm. Locoregional progression was less frequent in those randomly assigned to locoregional therapy (3-year rate: 16.3% v 39.8%; P < .001). Quality-of-life measures were largely similar between arms. CONCLUSION: Early locoregional therapy for the primary site did not improve survival in patients presenting with metastatic breast cancer. Although it was associated with improved locoregional control, this had no overall impact on quality of life.

Comparison of Radiation With or Without Concurrent Trastuzumab for HER2-Positive Ductal Carcinoma In Situ Resected by Lumpectomy: A Phase III Clinical Trial.

PURPOSE: Preclinical studies report that trastuzumab (T) can boost radiotherapy (RT) effectiveness. The primary aim of the B-43 trial was to assess the efficacy of RT alone vs concurrent RT plus T in preventing recurrence of ipsilateral breast cancer (IBTR) in women with ductal carcinoma in situ (DCIS). PATIENTS AND METHODS: Eligibility: Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, DCIS resected by lumpectomy, known estrogen receptor (ER) and/or progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) status by centralized testing. Whole-breast RT was given concurrently with T. Stratification was by menopausal status, adjuvant endocrine therapy plan, and nuclear grade. Definitive intent-to-treat primary analysis was to be conducted when either 163 IBTR events occurred or all accrued patients were on study ≥ 5 years. RESULTS: There were 2,014 participants who were randomly assigned. Median follow-up time as of December 31, 2019, was 79.2 months. At primary definitive analysis, 114 IBTR events occurred: RT arm, 63 and RT plus T arm, 51 (hazard ratio [HR], 0.81; 95% CI, 0.56 to 1.17; P value = .26). There were 34 who were invasive: RT arm, 18 and RT plus T arm, 20 (HR, 1.11; 95% CI, 0.59 to 2.10; P value = .71). Seventy-six were DCIS: RT arm, 45 and RT plus T arm, 31 (HR, 0.68; 95% CI, 0.43 to 1.08; P value = .11). Annual IBTR event rates were: RT arm, 0.99%/y and RT plus T arm, 0.79%/y. The study did not reach the 163 protocol-specified events, so the definitive analysis was triggered by all patients having been on study for ≥ 5 years. CONCLUSION: Addition of T to RT did not achieve the objective of 36% reduction in IBTR rate but did achieve a modest but statistically nonsignificant reduction of 19%. Nonetheless, this trial had negative results. Further exploration of RT plus T is needed in HER2-positive DCIS before its routine delivery in patients with DCIS resected by lumpectomy.

A qualitative study to evaluate physician attitudes regarding omission of surgery among exceptional responders to neoadjuvant systemic therapy for breast cancer (NRG-CC006).

PURPOSE: Accrual to clinical trials that challenge well-established treatment paradigms represents a unique challenge. Physician opinions on investigation of a novel approach to breast cancer treatment, in which patients with complete response to neoadjuvant chemotherapy are offered omission of lumpectomy, are unknown. NRG-CC006 sought to describe physician attitudes toward a novel approach to breast cancer treatment. METHODS: We recruited 18 participants in the fields of surgery, medical oncology, and radiation oncology to participate in the semi-structured telephone interviews. Main outcomes are qualitative themes associated with omission of surgery. RESULTS: Of 18 interview participants, specialty and gender were evenly represented across surgery, medical oncology, and radiation oncology. Qualitative themes included general attitudes toward treatment de-escalation, stakeholder considerations, and trial/protocol considerations. The vast majority of participants expressed interest in investigation of omission of surgery, with all participants endorsing need for further investigation into treatment de-escalation. Stakeholder considerations in opening such a trial emphasized need for multidisciplinary involvement and, particularly, the unique role of surgeons as gatekeepers in breast cancer treatment. Finally, participants endorsed a need for further foundational studies to develop ways to predict complete pathologic response to chemotherapy without surgical intervention. CONCLUSIONS: Physicians expressed interest in investigating a novel approach to breast cancer treatment that would omit surgery in complete responders to neoadjuvant chemotherapy. Multidisciplinary input, and specifically surgeon engagement, will be key to the success of future investigations. Ongoing work to develop approaches to predict pathologic complete response accurately is needed to achieve the promise of this idea. ClinTrials #: BR005: NCT03188393 June 13, 2017.

The ongoing evaluation and evolution of breast cancer surgical care.

Surgery has always been the backbone of breast cancer management. Throughout the past century, there have been great advances in chemotherapy regimens, especially in the neo-adjuvant setting. As a result of this progress, a patient's disease can be potentially down-staged and thus surgical intervention can therefore be de-escalated for the breast as well as the axilla. Current clinical trials are evaluating the role of imaging and core needle biopsy as predictive tools for the efficacy of neo-adjuvant chemotherapy. Results from these trials may help to clarify how the intricate relationship among imaging, pathology, radiotherapy, and surgery will affect the future management of patients undergoing neo-adjuvant chemotherapy for invasive breast cancer.

Long-term primary results of accelerated partial breast irradiation after breast-conserving surgery for early-stage breast cancer: a randomised, phase 3, equivalence trial.

BACKGROUND: Whole-breast irradiation after breast-conserving surgery for patients with early-stage breast cancer decreases ipsilateral breast-tumour recurrence (IBTR), yielding comparable results to mastectomy. It is unknown whether accelerated partial breast irradiation (APBI) to only the tumour-bearing quadrant, which shortens treatment duration, is equally effective. In our trial, we investigated whether APBI provides equivalent local tumour control after lumpectomy compared with whole-breast irradiation. METHODS: We did this randomised, phase 3, equivalence trial (NSABP B-39/RTOG 0413) in 154 clinical centres in the USA, Canada, Ireland, and Israel. Adult women (>18 years) with early-stage (0, I, or II; no evidence of distant metastases, but up to three axillary nodes could be positive) breast cancer (tumour size ≤3 cm; including all histologies and multifocal breast cancers), who had had lumpectomy with negative (ie, no detectable cancer cells) surgical margins, were randomly assigned (1:1) using a biased-coin-based minimisation algorithm to receive either whole-breast irradiation (whole-breast irradiation group) or APBI (APBI group). Whole-breast irradiation was delivered in 25 daily fractions of 50 Gy over 5 weeks, with or without a supplemental boost to the tumour bed, and APBI was delivered as 34 Gy of brachytherapy or 38·5 Gy of external bream radiation therapy in 10 fractions, over 5 treatment days within an 8-day period. Randomisation was stratified by disease stage, menopausal status, hormone-receptor status, and intention to receive chemotherapy. Patients, investigators, and statisticians could not be masked to treatment allocation. The primary outcome of invasive and non-invasive IBTR as a first recurrence was analysed in the intention-to-treat population, excluding those patients who were lost to follow-up, with an equivalency test on the basis of a 50% margin increase in the hazard ratio (90% CI for the observed HR between 0·667 and 1·5 for equivalence) and a Cox proportional hazard model. Survival was assessed by intention to treat, and sensitivity analyses were done in the per-protocol population. This trial is registered with ClinicalTrials.gov, NCT00103181. FINDINGS: Between March 21, 2005, and April 16, 2013, 4216 women were enrolled. 2109 were assigned to the whole-breast irradiation group and 2107 were assigned to the APBI group. 70 patients from the whole-breast irradiation group and 14 from the APBI group withdrew consent or were lost to follow-up at this stage, so 2039 and 2093 patients respectively were available for survival analysis. Further, three and four patients respectively were lost to clinical follow-up (ie, survival status was assessed by phone but no physical examination was done), leaving 2036 patients in the whole-breast irradiation group and 2089 in the APBI group evaluable for the primary outcome. At a median follow-up of 10·2 years (IQR 7·5-11·5), 90 (4%) of 2089 women eligible for the primary outcome in the APBI group and 71 (3%) of 2036 women in the whole-breast irradiation group had an IBTR (HR 1·22, 90% CI 0·94-1·58). The 10-year cumulative incidence of IBTR was 4·6% (95% CI 3·7-5·7) in the APBI group versus 3·9% (3·1-5·0) in the whole-breast irradiation group. 44 (2%) of 2039 patients in the whole-breast irradiation group and 49 (2%) of 2093 patients in the APBI group died from recurring breast cancer. There were no treatment-related deaths. Second cancers and treatment-related toxicities were similar between the two groups. 2020 patients in the whole-breast irradiation group and 2089 in APBI group had available data on adverse events. The highest toxicity grade reported was: grade 1 in 845 (40%), grade 2 in 921 (44%), and grade 3 in 201 (10%) patients in the APBI group, compared with grade 1 in 626 (31%), grade 2 in 1193 (59%), and grade 3 in 143 (7%) in the whole-breast irradiation group. INTERPRETATION: APBI did not meet the criteria for equivalence to whole-breast irradiation in controlling IBTR for breast-conserving therapy. Our trial had broad eligibility criteria, leading to a large, heterogeneous pool of patients and sufficient power to detect treatment equivalence, but was not designed to test equivalence in patient subgroups or outcomes from different APBI techniques. For patients with early-stage breast cancer, our findings support whole-breast irradiation following lumpectomy; however, with an absolute difference of less than 1% in the 10-year cumulative incidence of IBTR, APBI might be an acceptable alternative for some women. FUNDING: National Cancer Institute, US Department of Health and Human Services.

Lymphedema symptoms and limb measurement changes in breast cancer survivors treated with neoadjuvant chemotherapy and axillary dissection: results of American College of Surgeons Oncology Group (ACOSOG) Z1071 (Alliance) substudy.

PURPOSE: Lymphedema is a potential complication of breast cancer treatment. This longitudinal substudy aimed to prospectively assess arm measurements and symptoms following neoadjuvant chemotherapy and axillary dissection in the ACOSOG/Alliance Z1071 trial to characterize the optimal approach to define lymphedema. METHODS: Z1071 enrolled patients with cT0-4, N1-2, M0 disease treated with neoadjuvant chemotherapy. All patients underwent axillary dissection. Bilateral limb volumes, circumferences, and related symptoms were assessed pre-surgery, 1-2 weeks post-surgery, and semiannually for 36 months. Lymphedema definitions included volume increase ≥ 10% or limb circumference increase ≥ 2 cm. Symptoms were assessed by the Lymphedema Breast Cancer Questionnaire. RESULTS: In 488 evaluable patients, lymphedema incidence at 3 years by ≥ 10%-volume-increase was 60.3% (95% CI 55.0-66.2%) and by ≥ 2 cm-circumference increase was 75.4% (95% CI 70.8-80.2%). Symptoms of arm swelling and heaviness decreased from post-surgery for the first 18 months and then were relatively stable. The 3-year cumulative incidence of arm swelling and heaviness was 26.0% (95% CI 21.7-31.1%) and 30.9% (95% CI 26.3-36.3%), respectively. There was limited agreement between the two measurements (kappa 0.27) and between symptoms and measurements (kappa coefficients ranging from 0.05-0.09). CONCLUSIONS: Lymphedema incidence by limb volume and circumference gradually increased over 36 months post-surgery, whereas lymphedema symptoms were much lower. These findings underscore the importance of prospective surveillance and evaluation of both limb measurements and symptom assessment. Lymphedema incidence rates varied by definition. We recommend that ≥ 10% volume change criterion be used for lymphedema evaluation for referral for specialist care. TRIAL REGISTRATION: NCT00881361.

Randomized Phase II Study Evaluating Palbociclib in Addition to Letrozole as Neoadjuvant Therapy in Estrogen Receptor-Positive Early Breast Cancer: PALLET Trial.

PURPOSE: CDK4/6 inhibitors are used to treat estrogen receptor (ER)-positive metastatic breast cancer (BC) in combination with endocrine therapy. PALLET is a phase II randomized trial that evaluated the effects of combination palbociclib plus letrozole as neoadjuvant therapy. PATIENTS AND METHODS: Postmenopausal women with ER-positive primary BC and tumors greater than or equal to 2.0 cm were randomly assigned 3:2:2:2 to letrozole (2.5 mg/d) for 14 weeks (A); letrozole for 2 weeks, then palbociclib plus letrozole to 14 weeks (B); palbociclib for 2 weeks, then palbociclib plus letrozole to 14 weeks (C); or palbociclib plus letrozole for 14 weeks. Palbociclib 125 mg/d was administered orally on a 21-days-on, 7-days-off schedule. Core-cut biopsies were taken at baseline and 2 and 14 weeks. Coprimary end points for letrozole versus palbociclib plus letrozole groups (A v B + C + D) were change in Ki-67 (protein encoded by the  MKI67 gene; immunohistochemistry) between baseline and 14 weeks and clinical response (ordinal and ultrasound) after 14 weeks. Complete cell-cycle arrest was defined as Ki-67 less than or equal to 2.7%. Apoptosis was characterized by cleaved poly (ADP-ribose) polymerase. RESULTS: Three hundred seven patients were recruited. Clinical response was not significantly different between palbociclib plus letrozole and letrozole groups ( P = .20; complete response + partial response, 54.3% v 49.5%), and progressive disease was 3.2% versus 5.4%, respectively. Median log-fold change in Ki-67 was greater with palbociclib plus letrozole compared with letrozole (-4.1 v -2.2; P < .001) in the 190 evaluable patients (61.9%), corresponding to a geometric mean change of -97.4% versus -88.5%. More patients on palbociclib plus letrozole achieved complete cell-cycle arrest (90% v 59%; P < .001). Median log-fold change (suppression) of cleaved poly (ADP-ribose) polymerase was greater with palbociclib plus letrozole versus letrozole (-0.80 v -0.42; P < .001). More patients had grade 3 or greater toxicity on palbociclib plus letrozole (49.8% v 17.0%; P < .001) mainly because of asymptomatic neutropenia. CONCLUSION: Adding palbociclib to letrozole significantly enhanced the suppression of malignant cell proliferation (Ki-67) in primary ER-positive BC, but did not increase the clinical response rate over 14 weeks, which was possibly related to a concurrent reduction in apoptosis.

Effects of Radiotherapy in Early-Stage, Low-Recurrence Risk, Hormone-Sensitive Breast Cancer.

Background: Radiotherapy after breast conservation has become the standard of care. Prior meta-analyses on effects of radiotherapy predated availability of gene expression profiling (GEP) to assess recurrence risk and/or did not include all relevant outcomes. This analysis used GEP information with pooled individual-level data to evaluate the impact of omitting radiotherapy on recurrence and mortality. Methods: We considered trials that evaluated or administered radiotherapy after lumpectomy in women with low-risk breast cancer. Women included had undergone lumpectomy and were treated with hormonal therapy for stage I, ER+ and/or PR+, HER2- breast cancer with Oncotype scores no greater than 18. Recurrence-free interval (RFI), type of RFI (locoregional or distant), and breast cancer-specific and overall survival were compared between no radiotherapy and radiotherapy using adjusted Cox models. All statistical tests were two-sided. Results: The final sample included 1778 women from seven trials. Omission of radiotherapy was associated with an overall adjusted hazard ratio of 2.59 (95% confidence interval [CI] = 1.38 to 4.89, P = .003) for RFI. There was a statistically significant increase in any first locoregional recurrence (P = .001), but not distant recurrence events (P = .90), or breast cancer-specific (P = .85) or overall survival (P = .61). Five-year RFI rate was high (93.5% for no radiotherapy vs 97.9% for radiotherapy; absolute reduction = 4.4%, 95% CI = 0.7% to 8.1%, P = .03). The effects of radiotherapy varied across subgroups, with lower RFI rates for those with Oncotype scores of less than 11 (vs 11-18), older (vs younger), and ER+/PR+ status (vs other). Conclusions: Omission of radiotherapy in hormone-sensitive patients with low recurrence risk may lead to a modest increase in locoregional recurrence event rates, but does not appear to increase the rate of distant recurrence or death.

Simulation Modeling of Cancer Clinical Trials: Application to Omitting Radiotherapy in Low-risk Breast Cancer.

Background: We used two models to simulate a proposed noninferiority trial of radiotherapy (RT) omission in low-risk invasive breast cancer to illustrate how modeling could be used to predict the trial's outcomes, inform trial design, and contribute to practice debates. Methods: The proposed trial was a prospective randomized trial of no-RT vs RT in women age 40 to 74 years undergoing lumpectomy and endocrine therapy for hormone receptor-positive, human epidermal growth factor receptor 2-negative, stage I breast cancer with an Oncotype DX score of 18 or lower. The primary endpoint was recurrence-free interval (RFI), including locoregional recurrence, distant recurrence, and breast cancer death. Noninferiority required the two-sided 90% confidence interval of the RFI hazard ratio (HR) for no-RT vs RT to be entirely below 1.7. Model inputs included published data. The trial was simulated 1000 times, and results were summarized as percent concluding noninferiority and mean (standard deviation) of hazard ratios for Model GE and Model M, respectively. Results: Noninferiority was demonstrated in 18.0% and 3.7% for the two models. The respective means (SD) of the RFI hazard ratios were 1.8 (0.7) and 2.4 (0.9); most were locoregional recurrences. The mean five-year RFI rates for no-RT vs RT (SD) were 92.7% (2.9%) vs 95.5% (2.2%) and 88.4% (2.0%) vs 94.5% (1.6%). Both models showed little or no difference in breast cancer-specific or overall survival. Alternative definitions of low risk based on combinations of age and grade produced similar results. Conclusions: The proposed trial was unlikely to show noninferiority of omitting radiotherapy even using alternative definitions of low-risk, as the endpoint included local recurrence. Future trials regarding radiotherapy should address absolute reduction in recurrence and impact of type of recurrence on the patient.

Long-term Peripheral Neuropathy in Breast Cancer Patients Treated With Adjuvant Chemotherapy: NRG Oncology/NSABP B-30.

Background: The long-term effects of chemotherapy are sparsely reported. Peripheral neuropathy (PN) is one of the most frequent toxicities associated with taxane use for the treatment of early-stage breast cancer. We investigated the impact of the three different docetaxel-based regimens and patient characteristics on long-term, patient-reported outcomes of PN and the impact of PN on long-term quality of life (QOL). Methods: The National Surgical Adjuvant Breast and Bowel Project Protocol B-30 was a randomized trial comparing sequential doxorubicin (A) and cyclophosphamide (C) followed by docetaxel (T) (AC→T), concurrent ACT, or AT in women with node-positive, early-stage breast cancer. The AC→T group had a higher cumulative dose of T. PN was one of the symptoms assessed in a QOL substudy. Statistical methods included simple and mixed ordinal logistic regression and general linear models. All statistical tests were two-sided. Results: Of 1512 patients, 41.9% reported PN two years after treatment initiation. Treatment with AT and ACT was associated with less severe long-term PN compared with AC→T (odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.35 to 0.58; OR = 0.59, 95% CI = 0.46 to 0.75). Preexisting PN, older age, obesity, mastectomy, and greater number of positive nodes were also associated with higher risk of long-term PN. Patients who reported worse PN symptoms at 24 months had statistically significantly worse QOL (Ptrend < .001). Conclusions: The administration of docetaxel is associated with long-term PN. The lower rate of long-term PN in AT and ACT patients might be an important consideration in supporting choosing these therapies for individuals with preexisting neuropathic symptoms or other risk factors for neuropathy.

Short-Term Follow-Up Mammography in Breast Conservation Therapy Likely Leads to Unnecessary Downstream Workup: A Longitudinal Study.

PURPOSE: To analyze the effect of post-radiation therapy (XRT) mammographic timing and radiation technique in relation to additional downstream workup for 569 breast conservation therapy patients treated with adjuvant XRT after their initial surveillance mammogram (MMG). METHODS AND MATERIALS: From January 2011 to December 2014, 569 breast cancer patients treated with breast conservation surgery and adjuvant XRT with a follow-up MMG were reviewed. Patients were stratified by the time interval until their first post-XRT MMG, and by XRT technique-whole breast (472), accelerated partial breast (96), conventional fractionation (373), hypofractionation (94), surgical cavity boosts (407), or no boost (66). The primary endpoint was further imaging after the initial MMG. RESULTS: Additional workup for those receiving an MMG within 3 months of completing XRT was 51% (73 of 143), compared with 40% (84 of 210) with MMG between 3 and 6 months and 34.5% (75 of 216) with MMG after 6 months (P=.04). Radiation boost to the postoperative bed was associated with further downstream imaging, whereas accelerated partial-breast irradiation and hypofractionated treatment were not. CONCLUSIONS: Breast conservation therapy patients who underwent screening MMG before 6 months after completion of XRT were more likely to undergo downstream workup, including additional biopsies. Accelerated and hypofractionated radiation techniques were not associated with supplementary workup. Further study is needed to assess appropriate selection of high-risk patients and possible negative implications of earlier post-XRT screening MMG.

21-Gene Recurrence Score for prognosis and prediction of taxane benefit after adjuvant chemotherapy plus endocrine therapy: results from NSABP B-28/NRG Oncology.

BACKGROUND: The 21-gene recurrence score (RS) predicts outcome and benefit from adjuvant chemotherapy benefit in breast cancer patients treated with adjuvant endocrine therapy. In the NSABP B-28 study, we evaluated the 21-gene RS for its prognostic impact and its ability to predict benefit from paclitaxel (P) in node-positive, estrogen receptor-positive (ER+) breast cancer patients treated with adjuvant chemotherapy plus tamoxifen. METHODS: The B-28 trial compared doxorubicin/cyclophosphamide (AC) with AC followed by P in 3060 patients. Tamoxifen for 5 years was also given to patients > 50 years and those < 50 years with ER+ and/or progesterone receptor-positive (PR+) tumors. The present study includes 1065 ER-positive, tamoxifen-treated patients with RS assessment. Median follow-up time was 11.2 years. RESULTS: In univariate analyses, RS was a significant predictor of outcome. In multivariate analyses, RS remained a significant independent predictor of outcome beyond clinico-pathologic factors, age, and type of surgery (p < 0.001). In the study population (n = 1065), the disease-free survival (DFS) hazard ratio (HR) with adding P to AC was 0.87 (95% CI 0.72-1.05; p = 0.14). RS was not a significant predictor of P benefit: for DFS, HRs for adding P to AC in RS low, intermediate, and high subgroups were 1.01 (95% CI 0.69-1.47; p = 0.99), 0.84 (95% CI 0.62-1.14; p = 0.26), and 0.81 (95% CI 0.60-1.10; p = 0.21), respectively (interaction p = 0.64). Similar findings were observed for the other study endpoints. CONCLUSIONS: RS maintains significant prognostic impact in ER-positive, node-positive patients treated with adjuvant chemotherapy plus tamoxifen. However, RS did not significantly predict benefit from adding paclitaxel to AC chemotherapy. (Trial Registration: PDQ: NSABP-B-28).

Tumor Biology and Response to Chemotherapy Impact Breast Cancer-specific Survival in Node-positive Breast Cancer Patients Treated With Neoadjuvant Chemotherapy: Long-term Follow-up From ACOSOG Z1071 (Alliance).

BACKGROUND: Women with node-positive breast cancer are at high risk for recurrence. We evaluate the impact of approximated tumor subtype and response to chemotherapy on long-term outcomes in a node-positive cohort receiving neoadjuvant chemotherapy. METHODS: ACOSOG Z1071 enrolled cT0-4N1-2 breast cancer patients treated with neoadjuvant chemotherapy from 2009 to 2011. Factors impacting breast cancer-specific survival (BCSS) and overall survival (OS) were analyzed. RESULTS: Median follow-up of 701 eligible patients was 4.1 years (0.4-6.5). Ninety patients (12.8%) died from breast cancer. Approximated subtype and chemotherapy response were significantly associated with BCSS and OS (P < 0.0001). BCSS and OS were highest in patients who achieved pathologic complete response (pCR) (P < 0.0001 and P < 0.0001, respectively).Five-year BCSS was highest in human epidermal growth factor receptor 2 (HER2)-positive disease [95.8%; 95% confidence interval (CI): 87.7-98.6], followed by hormone receptor-positive/HER2-negative (80.4%; 95% CI: 73.2-85.9) and lowest in triple-negative (TNBC) (74.8%; 95% CI: 66.6-81.2; P < 0.0001). Similar patterns were seen in OS.In TNBC (n = 174), 5-year BCSS was higher in patients with pCR versus residual disease (89.8%; 95% CI: 78.8-95.3 vs 65.8%; 95% CI: 54.5-74.9; P = 0.0013). In hormone receptor-positive/HER2-negative (n = 318) disease, BCSS was 100% in patients with pCR and 78.3% (95% CI: 70.4-84.3) in those with residual disease (P = 0.018). In HER2-positive disease (n = 204) there was no difference between pCR and residual disease (96.0%; 95% CI: 83.6-99.1 vs 95.8%; 95% CI: 81.4-99.1; P = 0.77). CONCLUSIONS: In node-positive breast cancer patients treated with neoadjuvant chemotherapy, BCSS and OS were associated with approximated subtype and chemotherapy response and were lowest in TNBC patients with residual disease. Five-year BCSS was > 95% in HER2-positive disease independent of chemotherapy response.

Local failure and acute radiodermatological toxicity in patients undergoing radiation therapy with and without postmastectomy chest wall bolus: Is bolus ever necessary?

PURPOSE: Postmastectomy chest wall radiation therapy has historically used bolus to increase dose at the skin surface. Despite the theoretical benefits of bolus, the clinical implications of locoregional tumor control, cosmesis, and the incidence of radiodermatitis are less well characterized. We hypothesized that treatment in the presence or absence of bolus results in equivalent chest wall recurrence rates, but its presence results in more severe acute dermatologic toxicity. METHODS AND MATERIALS: Locally advanced breast cancer patients undergoing chest wall radiation therapy were retrospectively reviewed from 2005 to 2015 (n = 106; 53 with bolus, 53 without). Outcomes including local failure, acute skin toxicity, and treatment interruptions were recorded. Median age was 59 years (range, 28-91) and median follow-up was 34 months. Histology was invasive ductal carcinoma (73%), invasive lobular carcinoma (20%), inflammatory (6%), and neuroendocrine (1%). Fifty-nine percent were T3/T4 primary tumors and 29.2% had clinical/pathologic skin involvement. Node-positive patients accounted for 80.2%. Chemotherapy was administered in 84.0%. All patients had 3-dimensional conformal radiation therapy and received a median dose of 61Gy (range, 50-63 Gy). RESULTS: Local failure was 6.6% (n = 7) overall, with 4 failures in the bolus group and 3 in the no bolus group. No pathological factors were associated with local failure. Acute grade 2 and 3 skin toxicities (37 vs 22) and treatment interruptions (20 vs 3) were more common in the bolus group (P < .05). Mean treatment interruption (14.5 vs 5 days) was longer for patients receiving bolus. Patients undergoing treatment interruption were more likely to fail locally than patients not requiring a treatment interruption (17.4% vs 3.6%, P = .0322). CONCLUSIONS: Bolus omission in adjuvant chest wall radiation therapy may be a reasonable approach to avoid acute skin toxicity and treatment interruptions while preserving local control; however, further study will be needed to reach a definitive conclusion.

Milestone clinical trials of the National Surgical Adjuvant Breast and Bowel Project (NSABP).

The National Surgical Adjuvant Breast and Bowel Project (NSABP) has made significant contributions in reducing the extent of breast surgery and in improving outcomes of patients with early-stage breast cancer through the conduct of large randomized clinical trials evaluating local and systemic therapy. In 2014, the NSABP merged with two other US National Cancer Institute-funded cooperative groups, the Radiation Therapy Oncology Group (RTOG) and the Gynecologic Oncology Group (GOG), to form NRG Oncology. The combined organization has 218 member institutions with more than 600 affiliate centers located throughout the United States, Canada, Puerto Rico, and other international sites. Over the past half century, the NSABP has entered more than 150,000 women into clinical trials of breast cancer treatment and breast cancer prevention. Many of these trials have been instrumental in establishing new standards of care for patients with breast cancer.

21-Gene Recurrence Score and Locoregional Recurrence in Node-Positive/ER-Positive Breast Cancer Treated With Chemo-Endocrine Therapy.

Background: The 21-gene recurrence score (RS) predicts risk of locoregional recurrence (LRR) in node-negative, estrogen receptor (ER)-positive breast cancer. We evaluated the association between RS and LRR in node-positive, ER-positive patients treated with adjuvant chemotherapy plus tamoxifen in National Surgical Adjuvant Breast and Bowel Project B-28. Methods: B-28 compared doxorubicin/cyclophosphamide (AC X 4) with AC X 4 followed by paclitaxel X 4. Tamoxifen was given to patients age 50 years or older and those younger than age 50 years with ER-positive and/or progesterone receptor-positive tumors. Lumpectomy patients received breast radiotherapy. Mastectomy patients received no radiotherapy. The present study includes 1065 ER-positive, tamoxifen-treated patients with RS assessment. Cumulative incidence functions and subdistribution hazard regression models were used for LRR to account for competing risks including distant recurrence, second primary cancers, and death from other causes. Median follow-up was 11.2 years. All statistical tests were one-sided. Results: There were 80 LRRs (7.5%) as first events (68% local/32% regional). RS was low: 36.2%; intermediate: 34.2%; and high: 29.6%. RS was a statistically significant predictor of LRR in univariate analyses (10-year cumulative incidence of LRR = 3.3%, 7.2%, and 12.2% for low, intermediate, and high RS, respectively, P < .001). In multivariable regression analysis, RS remained an independent predictor of LRR (hazard ratio [HR] = 2.59, 95% confidence interval [CI] = 1.28 to 5.26, for a 50-point difference, P = .008) along with pathologic nodal status (HR = 1.91, 95% CI = 1.20 to 3.03, for four or more vs one to three positive nodes, P = .006) and tumor size (HR = 1.28, 95% CI = 1.05 to 1.55, for a 1 cm difference, P = .02). Conclusions: RS statistically significantly predicts risk of LRR in node-positive, ER-positive breast cancer patients after adjuvant chemotherapy plus tamoxifen. These findings can help in the selection of appropriate candidates for comprehensive radiotherapy.

Anastrozole versus tamoxifen in postmenopausal women with ductal carcinoma in situ undergoing lumpectomy plus radiotherapy (NSABP B-35): a randomised, double-blind, phase 3 clinical trial.

BACKGROUND: Ductal carcinoma in situ is currently managed with excision, radiotherapy, and adjuvant hormone therapy, usually tamoxifen. We postulated that an aromatase inhibitor would be safer and more effective. We therefore undertook this trial to compare anastrozole versus tamoxifen in postmenopausal women with ductal carcinoma in situ undergoing lumpectomy plus radiotherapy. METHODS: The double-blind, randomised, phase 3 National Surgical Adjuvant Breast and Bowel Project (NSABP) B-35 trial was done in 333 participating NSABP centres in the USA and Canada. Postmenopausal women with hormone-positive ductal carcinoma in situ treated by lumpectomy with clear resection margins and whole-breast irradiation were enrolled and randomly assigned (1:1) to receive either oral tamoxifen 20 mg per day (with matching placebo in place of anastrozole) or oral anastrozole 1 mg per day (with matching placebo in place of tamoxifen) for 5 years. Randomisation was stratified by age (<60 vs ≥60 years) and patients and investigators were masked to treatment allocation. The primary outcome was breast cancer-free interval, defined as time from randomisation to any breast cancer event (local, regional, or distant recurrence, or contralateral breast cancer, invasive disease, or ductal carcinoma in situ), analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00053898, and is complete. FINDINGS: Between Jan 1, 2003, and June 15, 2006, 3104 eligible patients were enrolled and randomly assigned to the two treatment groups (1552 to tamoxifen and 1552 to anastrozole). As of Feb 28, 2015, follow-up information was available for 3083 patients for overall survival and 3077 for all other disease-free endpoints, with median follow-up of 9·0 years (IQR 8·2-10·0). In total, 212 breast cancer-free interval events occurred: 122 in the tamoxifen group and 90 in the anastrozole group (HR 0·73 [95% CI 0·56-0·96], p=0·0234). A significant time-by-treatment interaction (p=0·0410) became evident later in the study. There was also a significant interaction between treatment and age group (p=0·0379), showing that anastrozole is superior only in women younger than 60 years of age. Adverse events did not differ between the groups, except for thrombosis or embolism--a known side-effect of tamoxifen-for which there were 17 grade 4 or worse events in the tamoxifen group versus four in the anastrozole group. INTERPRETATION: Compared with tamoxifen, anastrozole treatment provided a significant improvement in breast cancer-free interval, mainly in women younger than 60 years of age. This finding means that women will benefit from having a choice of effective agents for ductal carcinoma in situ. FUNDING: US National Cancer Institute and AstraZeneca Pharmaceuticals LP.