Miao, Jieling

Abstract Background The phase III RxPONDER trial has affected treatment for node-positive (1-3), hormone receptor-positive, HER2-negative breast cancer with a 21-gene recurrence score (RS) less than 26. We investigated how these findings apply to different racial and ethnic groups within the trial. Methods The trial randomly assigned women to endocrine therapy (ET) or to chemotherapy plus ET. The primary clinical outcome was invasive disease-free survival (IDFS), with distant relapse-free survival (DRFS) as a secondary outcome. Multivariable Cox models were used to evaluate the association between race/ethnicity and survival outcomes, adjusting for clinicopathological characteristics, RS, and treatment. Results A total of 4048 women with self-reported race/ethnicity were included: Hispanic (15.1%), non-Hispanic Black (NHB) (6.1%), Native American/Pacific Islander (0.8%), Asian (8.0%), and non-Hispanic White (NHW) (70%). No differences in RS distribution, tumor size, or number of positive nodes were observed by race/ethnicity. Relative to NHWs, IDFS was worse for NHB participants (5-year IDFS 91.6% vs 87.1%, HR = 1.37; 95% CI = 1.03 to 1.81) and better for Asians (91.6% vs 93.9%, HR = 0.64; 95% CI = 0.46 to 0.91). Relative to NHW, DRFS was worse for NHB participants (5-year DRFS 95.8% vs 91.0%, HR = 1.65; 95% CI = 1.17 to 2.32) and better for Asians (95.8% vs 96.7%, HR = 0.59; 95% CI = 0.37 to 0.95). Adjusting for clinical characteristics, particularly body mass index, diminished the effect of race on outcomes. Chemotherapy treatment efficacy did not differ by race/ethnicity. Conclusions NHB women had worse clinical outcomes compared with NHWs in the RxPONDER trial despite similar RS and comparable treatment. Our study emphasizes the persistent racial disparities in breast cancer outcomes while highlighting complex interactions among contributing factors. Trial Registration ClinicalTrials.gov: NCT01272037.

PURPOSE Phosphatidylinositol 3-kinase/AKT-serine threonine kinase/mammalian target of rapamycin (mTOR) pathway abnormalities contribute to endocrine resistance. Everolimus, an mTOR inhibitor, improved progression-free survival in hormone receptor–positive metastatic breast cancer (BC) when combined with endocrine therapy (ET). In this phase III randomized, placebo-controlled trial, we assessed the efficacy of everolimus + ET as adjuvant therapy in high-risk, hormone receptor–positive, human epidermal growth factor receptor 2–negative BC after adjuvant/neoadjuvant chemotherapy. METHODS Patients were randomly assigned 1:1 to physician's choice ET and 1 year of everolimus (10 mg orally once daily) or placebo stratified by risk group. The primary end point was invasive disease-free survival (IDFS) evaluated by a stratified log-rank test with the hazard ratio (HR) estimated by Cox regression. Subset analyses included preplanned evaluation by risk group and exploratory analyses by menopausal status and age. Secondary end points included overall survival (OS) and safety. Everolimus did not improve IDFS/OS when added to ET in patients with early-stage high-risk, hormone receptor–positive BC. RESULTS One thousand and nine hundred thirty-nine patients were randomly assigned with 1,792 eligible for analysis. Overall, no benefit of everolimus was seen for IDFS (HR, 0.94 [95% CI, 0.77 to 1.14]) or OS (HR, 0.97 [95% CI, 0.75 to 1.26]). The assumption of proportional hazards was not met suggesting significant variability in the HR over time since the start of treatment. In an unplanned subgroup analysis among postmenopausal patients (N = 1,221), no difference in IDFS (HR, 1.08 [95% CI, 0.86 to 1.36]) or OS (HR, 1.19 [95% CI, 0.89 to 1.60]) was seen. In premenopausal patients (N = 571), everolimus improved both IDFS (HR, 0.64 [95% CI, 0.44 to 0.94]) and OS (HR, 0.49 [95% CI, 0.28 to 0.86]). Treatment completion rates were lower in the everolimus arm compared with placebo (48% v 73%) with higher grade 3 and 4 adverse events (35% v 7%). CONCLUSION One year of adjuvant everolimus + ET did not improve overall outcomes. Subset analysis suggests mTOR inhibition as a possible target for patients who remain premenopausal after chemotherapy.

Abstract BACKGROUND: Abnormalities of the PI3kinase/AKT/mTOR signaling network are common in breast cancer (BC) and are associated with endocrine resistance. Everolimus, an mTOR-inhibitor increased PFS when combined with endocrine therapy (ET) in the metastatic setting and is thought to revert endocrine resistance. S1207 is a phase III randomized, placebo-controlled trial evaluating the role of everolimus in combination with ET in the adjuvant setting among patients with high-risk hormone receptor-positive, HER2-negative BC (NCT01674140). METHODS: Eligible patients were >18 years of age with histologically confirmed invasive hormone receptor-positive and HER2-negative high-risk BC. Four risk groups were defined as: 1) > 2cm node-negative disease (or pN1mi), and either an Oncotype DX® Recurrence Score (RS) > 25 or MammaPrint® high-risk category (MP high); 2) 1-3 positive nodes and either RS >25, MP high or a pathological grade 3 tumor; 3) >4 positive lymph nodes. Patients treated with neoadjuvant chemotherapy were eligible if: 4) after surgery had >1 lymph node involvement. Patients were randomized 1:1 to physician’s choice adjuvant ET in combination with one year of everolimus (10 mg PO daily) or ET plus placebo stratified by risk group. The primary endpoint was invasive disease-free survival (IDFS) evaluated by a stratified log-rank test. Secondary endpoints included overall survival (OS) and safety. The hazard ratio (HR) for treatment efficacy was estimated using Cox regression with stratification by risk groups. Subset analyses included preplanned evaluation within risk group and exploratory analyses of menopausal status and age. RESULTS: 1,939 patients were randomized between September 2013 and May 2019, of them 1,792 were eligible and included in the analysis (896 per arm). Primary reason for ineligibility was timing after chemotherapy/radiation or not high risk. Median age was 54 years (22-85) and 32% were premenopausal. With a median follow-up of 50.5 months, there were 389 IDFS events as of May 2022 (data cutoff). 5-year IDFS was 74.8% among patients treated with everolimus and 73.9% among patients treated with placebo, HR=0.93 (95% CI 0.76-1.14). However, the proportional hazards assumption was violated (p=0.02) suggesting differential treatment effect over time. The HR during the one year of treatment was 0.72 (95% CI 0.47-1.10) while after one year it was 1.00 (95% CI 0.80-1.26). The 5-year OS was 87.6% in the everolimus arm and 85.5% in the placebo arm, HR=0.98 (95% CI 0.75-1.28). Analysis by risk group did not show higher everolimus benefit as risk increased. No difference in IDFS or OS was seen among postmenopausal patients (IDFS HR=1.08 [95% CI 0.85-1.36], OS HR=1.19 [95% CI 0.87-1.61]). Among premenopausal patients, everolimus was associated with improved IDFS (HR=0.63 [95% CI 0.43-0.93]) and OS (HR=0.48 [95% CI 0.26-0.88]). Treatment completion of randomized therapy was lower in the everolimus arm compared to placebo (47.9% v 72.7%). Grade 3 and 4 toxicities were noted in 6.5% and 0.5% of patients in the placebo arm and in 31.2% and 3.7% in the everolimus arm respectively. CONCLUSIONS: Addition of one year of adjuvant everolimus to standard adjuvant ET did not improve IDFS or OS and was associated with low completion rate and increased AEs. Among premenopausal patients there was a benefit in IDFS and OS that is hypothesis generating. Future translational studies will evaluate potential predictors of everolimus benefit and drug toxicity. Citation Format: Marianna Chavez, Jieling Miao, Lajos Pusztai, Matthew P. Goetz, Priya Rastogi, Patricia A. Ganz, Eleftherios (Terry) Mamounas, Soonmyung Paik, Hanna Bandos, Wajeeha Razaq, Anne O’Dea, Virginia Kaklamani, Andrea L.M. Silber, Lisa E. Flaum, Eleni Andreopolu, Joseph Baar, Albert G. Wendt, Jennifer F. Carney, Priyanka Sharma, Julie R. Gralow, Danika L. Lew, William E. Barlow, Gabriel N. Hortobagyi. Results from a phase III randomized, placebo-controlled clinical trial evaluating adjuvant endocrine therapy +/- 1 year of everolimus in patients with high-risk hormone receptor-positive, HER2-negative breast cancer: SWOG S1207 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS1-07.

Abstract Background: We previouslyreported that invasive disease-free survival (IDFS), the primary outcome, and distantdisease-free survival (DDFS), a secondary outcome, differed by menopausalstatus in a pre-specified analysis. Here,we report updates on IDFS and DDFS with additional follow-up, as well as distantrecurrence-free interval (DRFI) and post hoc analyses in premenopausal women.Methods: Eligibilitycriteria included women > 18 years of age with HR+, HER2-BC and 1-3 +LN and no contraindications to taxane and/or anthracycline basedCT. DRFI was defined as time to distant recurrence or death from breast cancer.Analyses were intent-to-treat among eligible pts. We performed a post hocanalysis evaluating IDFS between treatment arms in premenopausal pts with pN1mi.In addition, we conducted a two-year landmarked IDFS analysis by ovarianfunction suppression (OFS) or not in the ET arm, as well as by regularmenstrual periods or not in both treatment arms.Results: Among the 4,984eligible pts, there were 553 IDFS events and median follow-up of 6.1 years.Postmenopausal women do not have any IDFS or DDFS benefit with CT; however, 5-yearabsolute benefits for IDFS and DDFS with CT for premenopausal pts were 5.9% and3.3%, respectively. In pre-menopausal pts, CT was associated with improved DRFIfor all RS values < 25, with an absolute improvement of 2.3% for RS0-13 and of 2.8% for RS 14-25. Among premenopausal pts, 12.4% (n=206) had pNmi)disease. In a post hoc analysis, there was a trend for CT benefit for thosewith pNmi [hazard ratio (HR)=0.44, confidence interval (CI)=0.18-1.08]. Therewere only 22 IDFS events. Only 17.2% of premenopausal pts assigned to ETunderwent OFS in the first 24 months and in two-year landmarked analysis, therewas no IDFS difference in those who underwent OFS or not (HR=0.88,CI=0.47-1.63). In premenopausal women assigned to ET, 58.9% stopped havingperiods within the first 24 months, and have anumerically improved IDFS compared to those who continued regular periods (HR=1.48,CI: 0.92-2.40). Among premenopausal assigned to CT followed by ET, 80.8%stopped having periods within the first 24 months and have a numericallyimproved IDFS compared to those who continue to have regular periods (HR=1.56, CI:0.85-2.86).Discussion: In accordancewith the differential IDFS and DDFS benefit based upon menopausal status inS1007, premenopausal pts with 1-3+LN and RS < 25 had a statisticallysignificant improvement in DRFI with the addition of CT. A small proportion of S1007premenopausal participants underwent OFS. The role of OFS as it relates to CTbenefit cannot be determined from this study. A future randomized trial should address the clinical question if OFScan replace CT in premenopausal pts with HR+/HER2-, node-positive breast cancer.Funding: Supported by National Cancer Institute grants U10CA180888, U10CA180819,U10CA180820, U10CA180821, U10CA180868, U10CA180863, and in part by Susan G.Komen for the Cure® Research Program, The Hope Foundation for Cancer Research,Breast Cancer Research Foundation, and Genomic Health, Inc. Citation Format: Kevin M Kalinsky, William E Barlow, Julie R Gralow, Funda Meric-Bernstam, Kathy S Albain, Daniel F Hayes, Nancy U Lin, Edith A Perez, Lori A Goldstein, Stephen KL Chia, Sukhbinder Dhesy-Thind, Priya Rastogi, Emilio Alba, Suzette Delaloge, Miguel Martin, Catherine M Kelly, Manuel Ruiz-Borrego, Miguel Gil-Gil, Claudia H Arce-Salinas, Etienne GC Brain, Eun Sook Lee, Jean-Yves Pierga, Begoña Bermejo, Manuel Ramos-Vasquez, Kyung Hae Jung, Jean-Marc Ferrero, Anne Schott, Steven Shak, Priyanka Sharma, Danika Lew, Jieling Miao, Debasish Tripathy, Lajos Pusztai, Gabriel Hortobagyi. Updated results from a phase 3 randomized clinical trial in participants (pts) with 1-3 positive lymph nodes (LN), hormone receptor-positive (HR+) and HER2-negative (HER2-) breast cancer (BC) with recurrence score (RS) ≤ 25 randomized to endocrine therapy (ET) +/- chemotherapy (CT): SWOG S1007 (RxPONDER) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS2-07.

Abstract Funding: Supported by National Cancer Institute grants U10CA180888, U10CA180819, U10CA180820, U10CA180821, U10CA180868, U10CA180863; and in part by Susan G. Komen for the Cure® Research Program, The Hope Foundation for Cancer Research, Breast Cancer Research Foundation, and Genomic Health, Inc. Acknowledgement: The authors wish to thank Dr. Ana M. Gonzalez-Angulo, MD, for her invaluable contributions to the design and implementation of this study. Background: The clinical utility of the RS to determine CT benefit is well established in pts with HR+, HER2-, axillary lymph node (LN)-negative BC. Retrospective analyses from SWOG S8814 support the potential prognostic and predictive role of RS for CT benefit in postmenopausal pts with LN+ BC. SWOG S1007 is a prospective, randomized trial of endocrine therapy (ET) vs. chemoendocrine therapy (CET) in women with 1-3 +LN and a RS < 25 (NCT01272037). Methods: Eligibility criteria included women > 18 years of age with HR+, HER2- BC and 1-3 +LN and no contraindications to taxane and/or anthracycline based CT. Women with a RS < 25 were randomized to receive ET or CET in 1:1 randomization using 3 stratification factors: (1) RS (0-13 vs.14-25); (2) menopausal status; and (3) axillary nodal dissection vs. sentinel node biopsy. The primary objective was to determine the effect of CT on invasive disease-free survival (IDFS) and whether the effect depended on the RS. The primary analysis was to test for a significant interaction of the treatment arm and continuous RS using a Cox regression model for IDFS, adjusting for treatment, RS, and menopausal status. A total of 832 IDFS events were expected for the final analysis. Secondary objectives included overall survival (OS). The protocol specified that interaction between treatment and the stratification variables was to be tested and, if significant, separate analyses performed by stratum. Annual interim analyses were planned starting at 24% of events. At the third interim analysis with 410 IDFS events, the Data and Safety Monitoring Committee recommended reporting results, with a decision by the NCI’s Cancer Therapy Evaluation Program, the study sponsor. Results: Of the 9,383 women screened from 2/28/11-9/29/17, 5,083 pts (54.2%) were randomized. With a median follow-up of 5.1 years, 447 IDFS events have been observed. For the primary analysis, the interaction test for CT benefit and continuous RS was not statistically significant, p=0.30. In a model with CT, RS, and menopausal status (no interaction term), higher continuous RS was associated with worse IDFS [HR 1.06, 2-sided p<0.001, 95% Confidence Interval (CI) 1.04-1.07], and CT was associated with an improvement in IDFS (HR 0.81, p=0.026, 95% CI 0.67-0.98). In a pre-specified analysis, a significant interaction was identified between CT and menopausal status (p=0.004), necessitating separate analyses by menopausal status. In postmenopausal pts (N=3350, 67%), adjusting for continuous RS, the HR for CET vs. ET was not significant (HR=0.97, p=0.82, 95% CI 0.78-1.22; 5-year IDFS 91.6% vs. 91.9%) indicating no benefit from CT. In premenopausal pts (N=1665, 33%), the HR (0.54) was statistically significant (p=0.0004, 95% CI 0.38-0.76; 5-year IDFS 94.2% vs. 89.0%), indicating CT benefit. In premenopausal pts, ovarian suppression was performed in 15.9% vs. 3.7% (ET vs. CET), and 47.9% vs. 26.4% reported menstruation after 6 months of treatment. Although the number of events is limited, the HR for treatment adjusted by RS for OS in premenopausal pts was 0.47 (p=0.032, 95% CI 0.24-0.94). At this time, there is no differential effect with CT in regard to other stratification factors. Conclusions: There is a significant differential treatment effect of CT benefit based on RS for premenopausal vs. postmenopausal women requiring separate analyses. While only 54% of the protocol specified events are recorded and pts will be followed for 15 years, the current data show that adjuvant therapy can be de-escalated to ET alone in postmenopausal pts with a RS < 25 and 1-3 +LN. However, there is a strong IDFS benefit for CET in premenopausal pts, with an early indication of an OS improvement. Citation Format: Kevin Kalinsky, William E Barlow, Funda Meric-Bernstam, Julie R Gralow, Kathy S Albain, Daniel Hayes, Nancy Lin, Edith A Perez, Lori J Goldstein, Stephen Chia, Subkhbinder Dhesy-Thind, Priya Rastogi, Emilio Alba, Suzette Delaloge, Miguel Martín, Miguel Gil Gil, Claudia Arce-Salinas, Etienne Brain, In Hae Park, Jean-Yves Pierga, Ana Hernandez Lluch, Manuel Ramos Vasquez, Manuel Ruiz Borrego, Kyung Hae Jung, Jean-Marc Ferrero, Anne Schott, Steve Shak, Priyanka Sharma, Danika L Lew, Jieling Miao, Debu Tripathy, Gabriel Hortobagyi, Lajos Pusztai. First results from a phase III randomized clinical trial of standard adjuvant endocrine therapy (ET) +/- chemotherapy (CT) in patients (pts) with 1-3 positive nodes, hormone receptor-positive (HR+) and HER2-negative (HER2-) breast cancer (BC) with recurrence score (RS) < 25: SWOG S1007 (RxPonder) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS3-00.

Abstract Background: Evidence from randomized trials, including a recent meta-analysis, suggests that adjuvant bisphosphonates can decrease recurrence and death in postmenopausal women with early-stage breast cancer. Bisphosphonates (BP) have been included as adjuvant therapy for postmenopausal breast cancer patients in multiple guidelines. SWOG S0307 compared efficacy of 3 BPs in early stage breast cancer, with no evidence of differences in efficacy on breast cancer outcomes by type of bisphosphonate, either in the overall analysis or subgroups. BPs are generally well tolerated, with a relatively low risk of serious adverse effects. Treatment for hormone sensitive breast cancer frequently includes treatment with an aromatase inhibitor (AI) or ovarian function suppression (OFS), both of which can accelerate bone loss, decrease bone density, and increase fractures. In addition to decreasing breast cancer events, BPs have been shown to decrease fractures in breast cancer patients receiving AIs or OFS. However, concerns have been raised about the risk of atypical femur fractures (AFF), a rare subtype of fragility fractures, which appear to increase with longer BP use (3-100/100,000 person-years) (Shane 2013). This substudy evaluated all fractures occurring in patients enrolled on S0307. Methods: Patients with stage I-III breast cancer who were receiving adjuvant systemic therapy were randomized to receive 3 years of intravenous zoledronic acid (ZA) 4 mg IV given every 4 weeks for the first six months, and then every 3 months for the following 2.5 years, oral clodronate (CLOD) 1,600 mg/day orally, or oral ibandronate (IBAN) 50 mg/day orally. The primary endpoint was disease-free survival (DFS). On-treatment data collection forms specifically queried whether a fracture had occurred during the reporting period, the site of the fracture, and whether or not it was associated with trauma. Results: A total of 6,097 patients were randomized to S0307, with a median age of 53 years. Rates for overall fractures at 7.7 years were higher for CLOD (9.3%) compared to IBAN (7.4%) and ZA (7.1%) (p=0.02), with differences being mostly in the spine. Traumatic fracture differences were not significant (CLOD 2.0%, ZA 1.9%, IBAN 1.7%; p=0.83). Fragility fracture rates were 5.2% with ZA, 7.2% with CLOD, and 5.6% with IBAN. Ankle fractures were the most common fracture site at 2.8% overall. Leg fractures, including femur fractures, were relatively low with a rate of 1.5% overall and not different between agents. AFF were not specifically queried/determined. Conclusion: In S0307, BPs were used in higher doses than is recommended for treatment of postmenopausal osteoporosis. There is limited data comparing the long-term effects across BP drugs used at these higher doses on the skeleton. In S0307, an overall fracture rate of 8% was seen in early stage breast cancer patients despite receiving BPs along with conventional systemic therapy. Fracture rates were slightly higher for CLOD than ZA and IBAN for fragility and overall fractures, but similar for traumatic fractures. This may reflect the potency of CLOD or the dosing schedule. Rates of femur fractures were relatively low in all arms without evidence of excess femur fractures. Funding: NIH/NCI CA180888, CA180819, CA180820, CA180821, CA180868, CA180863, CA196175; BCRF, Komen, Berlex (Bayer), Roche/Genentech, Novartis. Citation Format: Rachel L (MD) Yung, Jieling Miao, Alexander HG Paterson, Mark Clemons, Elizabeth C Dees, James N Ingle, Carla I Falkson, William Barlow, Gabriel N Hortobagyi, Julie R Gralow. Fractures in women with breast cancer receiving high-dose bisphosphonates to prevent breast cancer metastases as part of the SWOG S0307 trial (ClinicalTrials.gov Identifier: NCT00127205) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P2-18-02.

Abstract Background Adjuvant bisphosphonates, when given in a low-estrogen environment, can decrease breast cancer recurrence and death. Treatment guidelines include recommendations for adjuvant bisphosphonates in postmenopausal patients. SWOG/Alliance/Canadian Cancer Trials Group/ECOG-ACRIN/NRG Oncology study S0307 compared the efficacy of three bisphosphonates in early-stage breast cancer. Methods Patients with stage I–III breast cancer were randomly assigned to 3 years of intravenous zoledronic acid, oral clodronate, or oral ibandronate. The primary endpoint was disease-free survival (DFS) with overall survival as a secondary outcome. All statistical tests were two-sided. Results A total of 6097 patients enrolled. Median age was 52.7 years. Prior to being randomly assigned, 73.2% patients indicated preference for oral vs intravenous formulation. DFS did not differ across arms in a log-rank test (P = .49); 5-year DFS was 88.3% (zoledronic acid: 95% confidence interval [CI] = 86.9% to 89.6%), 87.6% (clodronate: 95% CI = 86.1% to 88.9%), and 87.4% (ibandronate: 95% CI = 85.6% to 88.9%). Additionally, 5-year overall survival did not differ between arms (log rank P = .50) and was 92.6% (zoledronic acid: 95% CI = 91.4% to 93.6%), 92.4% (clodronate: 95% CI = 91.2% to 93.5%), and 92.9% (ibandronate: 95% CI = 91.5% to 94.1%). Bone as first site of recurrence did not differ between arms (P = .93). Analyses based on age and tumor subtypes showed no treatment differences. Grade 3/4 toxicity was 8.8% (zoledronic acid), 8.3% (clodronate), and 10.5% (ibandronate). Osteonecrosis of the jaw was highest for zoledronic acid (1.26%) compared with clodronate (0.36%) and ibandronate (0.77%). Conclusions We found no evidence of differences in efficacy by type of bisphosphonate, either in overall analysis or subgroups. Despite an increased rate of osteonecrosis of the jaw with zoledronic acid, overall toxicity grade differed little across arms. Given that patients expressed preference for oral formulation, efforts to make oral agents available in the United States should be considered.

552 Background: Bisphosphonates reduce the risk of bone metastases in postmenopausal women with early-stage breast cancer but carry the risk of osteonecrosis of the jaw (ONJ). We used the data collected in the S0307 trial to describe factors associated with provoked and unprovoked ONJ. Methods: In S0307, 6097 patients with Stage I-III breast cancer who had surgery were randomized to receive zoledronic acid (ZA) 4mg IV monthly for 6 months, then every 3 months, clodronate (CL) 1600mg daily, or ibandronate (IB) 50mg daily for three years, with no difference in bone metastases or disease-free survival. Patients completed dental procedures prior to and had a dental exam at enrollment. Pearson’s Chi-squared and Student’s T-test were used to test differences in categorical and continuous variables, respectively; logistic regression was used test independent association. Results: Of 5836 evaluable women, 48 developed ONJ, which was associated with bisphosphonate type (28/2124 (1.26%) for ZA, 8/2185 (0.36%) for CL and 12/1527 (0.77%) for IB (p = 0.002). Median time to onset of ONJ was 24.9 (1.4-66.6) for ZA, 41.2 months (range 33.8-67.4) for CL, 23.9 (2.1-75.3) for IB (p = 0.0447). Infection was present in 21 (43.8%) and absent in 20. ONJ was considered unprovoked in 20 (41.7%) and provoked by dental extraction in 20 (41.7%), periodontal disease in 14 (29.2%), denture trauma in 6 (12.5%), other dental surgery in 3 (6.3%). ONJ was associated with dental calculus (OR 2.03 (95% CI: 1.08-3.81), gingivitis (OR 2.11, 95% CI: 1.12-3.98), and periodontal disease (OR 2.87, 95% CI 1.45-5.53) that were moderate/severe and > 4mm periodontitis (OR 2.20, 95% CI 1.18-4.08). Patients with provoked and unprovoked ONJ had similar amounts of dental disease and lesion location. ONJ was not associated with dentures, plaque, chemotherapy, corticosteroids or renal adverse events. In multivariate analysis (limited by small sample), only bisphosphonate type was associated with ONJ. Conclusions: ONJ prevalence was low, likely due to patients completing dental procedures before enrollment. ZA carried a higher risk of ONJ (though current adjuvant dosing interval recommendations are less frequent), with time to onset similar to IB. Oral CL and IB (not currently available in the United States) are thus likely more appropriate for patients with poor dental health. Clinical trial information: NCT00127205.

Abstract Purpose: Statins may mediate suppression of molecular pathways conferring benefit in cancer. Statins have shown anti-tumor effects in preclinical studies and have been associated with decreased recurrence and improved disease-specific survival. While designed to target cholesterol biosynthesis, statins can also have liver, bone and brain effects. We collected data on statin use in the S0307 adjuvant bisphosphonate trial to test the hypothesis that statin use may decrease risk of recurrence to liver, bone and brain as well as second primary (contralateral) breast cancers, and may act synergistically with bisphosphonates to decrease the risk of recurrence to bone. Patients and Methods: In S0307, 6097 patients diagnosed with Stage I-III breast cancer who had undergone surgery and were receiving adjuvant systemic therapy were randomized to receive zoledronic acid, clodronate, or ibandronate for 3 years. No significant difference was found in disease-free survival (DFS) among the 3 groups, including a sub-analysis of patients > age 55. Statin use was infrequent in younger women in S0307, consequently we analyzed statin use in those > age 55. Cox proportional hazard models were used to determine which variables were independently associated with DFS and to estimate hazard ratios (HR) and 95% confidence intervals (CI). Results: Among women aged ≥ 55 years, 684 (27%) reported taking a statin at baseline and 1,848 did not. Both groups were similar in terms of hormone receptor and HER2 status (p = 0.82). Median age in the statin group was 64.3 versus 61.0 years in the no statin group, mean BMI 31.2 v. 29.5, mean tumor size 2.1cm v. 2.3cm, negative lymph nodes 60% v. 54%, Stage I disease 47% v. 36%, and receipt of chemotherapy 62% v. 71% (all p < 0.01). In the statin group, 122 (17.8%) experienced a DFS event compared to 313 (16.9%) in the no statin group (HR 1.18, CI 0.95-1.46). No difference was observed by statin use in overall recurrence (p=0.28), distant recurrence (p=0.64), or recurrences to the bone (p=0.64), liver (p=0.38) or brain (p=0.65) at initial recurrence. There was no synergy between statin use and specific bisphosphonates. Recurrence and statin useOutcomeGroup 1: On stan at baseline n=684Group 2: No statin at baseline n=1848DFS events122 (17.8%)313 (16.9%)Died without recurrence51 7.5%)97 (5.2%)Recurrence71 (10.4%)216 (11.7%)Contralateral breast cancer9 (1.3%)17 (0.9%)Distant recurrence48 (7%)157 (8.5%)Bone as 1st site of distant recurrence (% distant recurrence)31 (65%)76 (48%)Liver as 1st site of distant recurrence (% distant recurrence)6 (13%)24 (16%)Brain/CNS as 1st site of distant recurrence (% distant recurrence)5 (10%)17 (11%) Conclusions: We found no evidence that statins reduce risk of second primary breast cancers or distant metastases among post-menopausal women with early-stage breast cancer. Despite promising preclinical data, they did not appear to act in synergy with a specific bisphosphonate. Though women in the statin group had less advanced disease at study entry, statin use was not associated with improved DFS. Results are limited by lack of information about type of statin used, adherence, or initiation of statin in control group. Citation Format: Kizub D, Miao J, Stopeck A, Thompson P, Paterson AH, Clemons M, Dees EC, Ingle JN, Falkson CI, Barlow W, Hortobagyi GN, Gralow JR. Statin use, site of recurrence, and survival among post-menopausal women taking bisphosphonates as adjuvant therapy for breast cancer (SWOG S0307) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-17-03.