Loprinzi, CL

Abstract Background: Up to 68% of patients will experience CIPN. There are no FDA or ASCO recommended therapies. The pain (P), numbness (N), and tingling (T) can persist for month, years or even lifetime. Duloxetine reduces pain scores by 0.6-1.0 on the 0-10 scale but does not help N or T. Scrambler therapy (ST) is a novel form of neuromodulation that uses EKG electrodes on the dermatomes to capture the pain c-fiber receptors, and generate an action potential of “non-pain” information to replace the pain information. It appears to reset central sensitization by altering cerebral blood flow and re-establishing the balance of neuropeptides (e.g., NGF, GDNGF) in the blood (Smith et al NEJM 2023). Yet many professionals and patients are unaware of it. Methods: We reviewed all available studies. Results: Smith et al (2010, VCU) noted a 59% P reduction (5.8 to 2.4 at the end of 10 days (P<0.0001)) in 16 subjects, and 4 had 0 pain at day 10. Pachman et al (2015, Mayo) in 37 subjects showed a 53% P reduction by day 10; a 44% reduction in T; and a 37% reduction in N. In a randomized trial of 50 patients using ST versus TENS (transcutaneous electrical nerve stimulation), Loprinzi et al (2020, Mayo), in a randomized trial, showed more than twice as many ST patients reported a 50% improvement (36-56%) vs. TENS (16-28%). At 8 weeks the reductions were important: 33%P, 28%N, 41%T. In a subsequent crossover trial (Childs 2021) of the TENS patients to ST, 6 of 12 ST patients achieved a 50% reduction in P and T. Smith et al (2021 Hopkins) did a randomized sham-controlled trial with 35 patients but observed no lasting effect; in retrospect, the electrodes and electrode placement were incorrect in this trial. Abdi et al (2024, MDACC) did a Phase II trial of ST in 10 patients and found symptoms of N, T, trouble walking, and disturbed sleep had significant improvements at 6 months. Worst pain was reduced at 6 months by 3 points. Pain medication use decreased by 70% at the end of treatment and by 42% at 6 months. Patient satisfaction was high (82%) and no adverse events with ST treatment were reported. Wang Z. et al (Hopkins, unpublished data 2025) showed a 60% reduction in pain (6.2 to 2) in twelve subjects, with one achieving complete remission. Strouse et al (2025, UCLA) will soon report similar results in over 60 patients. Wang E. et al (2023, Hopkins) reviewed 1152 patients treated with ST and found just 3 adverse events: one hematoma and two red spots under the EKG electrodes. The only other therapy that reduces all the symptoms of CIPN is spinal cord stimulation (Gupta 2024) but that is invasive, expensive, and can cause a multitude of adverse events. Conclusions: Scrambler Therapy is a safe and effective treatment for the P, N, and T of CIPN with rare and minimal side effects in a syndrome with no other effective treatment. It is hindered by reimbursement ($32/30 minutes, the same as TENS even though the technology is completely different). Scrambler Therapy should become more available in the future. Citation Format: Z. Wang, C. L. Loprinzi, S. Abdi, T. B. Strouse, T. J. Smith. Scrambler Therapy: a safe and effective way to treat chemo-induced neuropathy [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS1-02-17.

9116 Background: Hot flashes affect 75 % to 90 % of women transitioning to menopause and are a major cause of morbidity among breast cancer survivors. Levetiracetam, a popular anticonvulsant, is a centrally active agent that anecdotally appeared to reduce hot flashes in clinical practice. This phase II trial sought to evaluate the efficacy of levetiracetam in reducing hot flashes among women with a history of breast cancer or women who did not wish to take estrogen therapy for fear of an increased risk of breast cancer. Methods: Women who were experiencing bothersome hot flashes (≥ 14 times per week, for ≥ 1 month) were eligible. A single arm pilot study design based on previous work was used with a planned sample size of 30 patients. The patients did not receive any study medication during the first week (baseline week). At the beginning of the second week, patients were started on levetiracetam (500 mg), and were to increase the dose by 500 mg each week to a goal of 1,000 mg twice daily. Hot flash diaries were completed daily. The primary endpoint was hot flash score (frequency times average severity). The change from week 1 (baseline) to week 5, the last treatment week, was analyzed by paired t-test and related Wilcoxon procedures. Results: A total of 30 women were enrolled onto this study in eight months. All patients were eligible. 19 women completed all 4 weeks of the study treatment and provided complete data. After treatment with levetiracetam for 4 weeks, mean hot flash scores were reduced by 57% (95% CI 39%-75%), while mean hot flash frequencies were reduced by 53% (95% CI 38%-68%), reductions being greater than what would be expected with a placebo. There were significant improvements, compared to baseline week data, in sweating, hot flash distress, and satisfaction with hot flash control. Eight subjects stopped the study drug due to treatment related adverse events (grade I/II), with the most frequently reported being somnolence, fatigue and dizziness. Conclusions: While levetiracetam appears to be a promising therapy for the treatment of hot flashes, further study is needed to better substantiate the toxicity and efficacy of this drug before it can be more definitively recommended for use in clinical practice. No significant financial relationships to disclose.

Abstract Background: The live attenuated non-pathogenic Edmonston MV vaccine strain has advantages as an oncolytic platform given its tumor specificity, potent bystander effect, and ability to be engineered and retargeted. MV-NIS expresses the human thyroidal sodium-iodide symporter (NIS) and is selectively oncolytic, entering tumor cells through CD46 (overexpressed on many cancers, including breast cancer of all subtypes) and Nectin-4. NIS expression in MV-NIS infected cells permits noninvasive monitoring of virus spread by SPECT-CT imaging of Tc-99m pertechnetate or I-123 uptake. Methods: NCT01846091 is a standard 3+3 phase I trial of a single IT administration of MV-NIS in pts with recurrent/metastatic squamous cell carcinoma of the head and neck (SCCHN) or metastatic breast cancer (MBC). Primary objectives are (a) safety and tolerability and (b) maximally tolerated single dose. The secondary clinical objective is to preliminarily assess antitumor efficacy at and away from the MV injection site. Key eligibility criteria were: absence of standard therapy with life prolonging intent; at least one lesion >1 cm amenable to percutaneous injection; and no impending visceral crisis. MV-NIS was administered on D1 with mandatory SPECT-CT at baseline (BL) and on D3&D8; repeat SPECT-CT on D15&D21 if the prior result was positive; mandatory tumor biopsies on D3&D21; optional tumor biopsies on D8&D15; assessments for viremia and viral shedding at BL and on D3,D8,D15,D21; and standard imaging for restaging at BL,D21,W6,W12. Results: Accrual completed with 12 evaluable pts (6 SCCHN and 6 MBC) at 3 dose levels (108, 3x108, 109 TCID50). The MBC group included 5 HR+/HER2- pts and 1 pt with mixed HR+/HER2- and HR+/HER2+ disease. 5 pts had evidence of disease progression prior to study participation. No dose limiting toxicities were observed among the MBC pts; AEs possibly related to MV-NIS in this group were gr2 fatigue, gr1 flu-like illness, gr2 lymphopenia (all n=1). No SCCHN responses were observed. Best response for the MBC pts was: stable disease (SD) >6 wks, n=4; clinical response, n=1; progression, n=1. One MBC pt with SD for 12 wks had positive SPECT/CT imaging at and away from the injection site on D3&D8 and was the only pt seronegative for measles IgG antibodies prior to MV-NIS exposure. The MBC pt who responded after initial MV-NIS exposure was the only pt with low viral RNA in blood (D3); she received additional doses at W9&W13 without toxicity through an expanded access protocol exemption and had disease progression by W19. No viral shedding was detected from mouth rinse or urine in any pt. MV was detected in tumor samples from all pts treated at the highest dose level. Additional blood and tissue analyses are in progress. Conclusion: These results demonstrate the safety of IT MV-NIS administration, provide early evidence of biologic activity in MBC, and support the possibility of viral replication in tumors remote from the IT injection site. A MV strain encoding the immunomodulatory neutrophil activating protein transgene has been constructed (MV-s-NAP) with preclinical evidence of improved antitumor activity and immunogenicity. The phase I MV-s-NAP trial will start recruitment in Fall 2018. Citation Format: Liu MC, Peng K-W, Federspiel MJ, Russell SJ, Brunton BA, Zhou Y, Packiriswamy N, Hubbard JM, Loprinzi CL, Peethambaram PP, Ruddy KJ, Allred JB, Galanis E, Okuno SH. Phase I trial of intratumoral (IT) administration of a NIS-expressing derivative manufactured from a genetically engineered strain of measles virus (MV) [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 P6-21-03.

Abstract Cyclin dependent kinase 4 and 6 inhibitors (CDK4/6i) are standard first line (1L) and second line (2L) treatments of ER+ MBC. However, the optimal treatment strategy after progression on a CDK 4/6i is unknown. Given concern for rapid disease progression after discontinuation of CDK4/6is (Bashour, J Cancer 2017), further data on responses to subsequent lines of therapy post CDK4/6i are needed. We performed a single institution retrospective review of patients (pts) with ER+ MBC who received 1L or 2L CDK4/6i to examine the prescribing patterns and clinical responses to post-CDK4/6i treatment. Methods: We identified 136 ER+ MBC pts prescribed a CDK4/6i at Mayo Clinic Rochester (from 12/2014 to 2/2018) on 1L or 2L who received at least 30 days of therapy and ≥ two clinic visits during treatment. For the 1L and 2L cohorts we assessed the time to treatment failure during (TTF-1) and after CDK4/6i therapy (TTF-2). TTF was defined as time from start of therapy to discontinuation for any cause. Additionally, we assessed overall survival (OS) post CDK4/6i discontinuation (defined as the date of TTF-1 to death or last follow up). Results: The study cohort included 81 and 55 pts treated with 1L and 2L CDK4/6is, respectively. In the 1L cohort, palbociclib/letrozole (82.3%) and palbociclib/fulvestrant (13.6%) were most commonly prescribed. Treatment was discontinued in 39/81 pts due to: progression (84.6%), intolerability (7.7%), and other (7.7%). The median TTF-1 was 19.7 mo (95% CI 11.2 – 25.4 mo). Subsequent treatment and response data were available in 37/39 pts that progressed on 1L CDK4/6i. The most commonly prescribed regimens included single-agent hormonal therapy (29.7%), everolimus/exemestane (27.0%), and single agent chemotherapy (21.7%). The overall median TTF-2 were as follows: everolimus/exemestane 13.2 mo [95%CI 0.33 mo – not reached (NR)]; single agent hormonal therapy 3.1 mo (95%CI 1.4 – 5.4 mo); and single agent chemotherapy 4.1 mo (95%CI 1.4 - 5.4 mo). With a median post-CDK4/6i follow up of 11.2 mo, we observed 8 deaths and the median OS-post CDK4/6i was NR. In the 2L cohort, common regimens were palbociclib/letrozole (63.6%) and palbociclib/fulvestrant (27.3%). Treatment was discontinued in 30/55 pts due to: progression (73.3%), intolerability (13.3%), and other (13.3%). The median TTF-1 in the 2L cohort was 8.3 mo (95%CI 4.6 – 12.7 mo). Subsequent treatment data were available in 24/30 pts and included single-agent hormonal therapy [n=7 (29.2%); median TTF-2 4.7 mo; 95%CI 1.9 – 14.0 mo], everolimus/exemestane [n=6 (25.0%); median TTF-2 3.2 mo, 95% CI 0.8-10.1 mo)] and single agent chemotherapy [n=6 (25.0%); median TTF-2 2.6 mo; 95%CI 1.7 mo – NR)]. With a median post-CDK4/6i follow up 18.7 mo in the 2L cohort, we observed 11 deaths, and the median OS-post CDK4/6i was 11.8 mo (95%CI 11.8 mo – NR). Conclusions: Single and combination-based endocrine strategies are commonly administered post-CDK4/6i without clinical evidence for rapid deterioration. The observation of a median treatment duration lasting >12 months in patients receiving everolimus/exemestane post-CDK4/6i supports ongoing studies evaluating drugs that target PI3K/mTOR pathway in combination and following progression on a CDK4/6i. Citation Format: Giridhar KV, Choong GM, Leon-Ferre RA, O'Sullivan CC, Ruddy KJ, Haddad TC, Hobday TJ, Peethambaram PP, Moynihan TJ, Loprinzi CL, Liu MC, Suman VJ, Goetz MP. Clinical management of metastatic breast cancer (MBC) after CDK 4/6 inhibitors: A retrospective single-institution study [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 P6-18-09.

Abstract Background: HF occur in about 75% of midlife women and are associated with quality of life disruption and premature endocrine therapy discontinuation among breast cancer survivors. Estrogen therapy, effective for HF, is contraindicated in hormone receptor-positive breast cancer (BC). Previous studies have suggested that Oxy could be effective in managing HF. Methods: This randomized, placebo (P)-controlled trial enrolled women who had experienced HF ≥28 times per week over >30 days and of sufficient severity to seek treatment. Patients (pts) were randomized to receive oral Oxy at two doses: 2.5mg BID for 6 weeks (Oxy2.5), 2.5mg BID for a week with subsequent increase to 5mg BID (Oxy5), or matching P, in equal ratios. Baseline and monthly questionnaires were administered including a HF diary, the HF related daily interference scale (HFRDIS) and a symptom experience questionnaire. The primary endpoint was intra-patient change in weekly HF score and frequency from baseline to end of study compared using Kruskal-Wallis tests. Results: 150 pts were accrued between 2/23/2017-3/5/2018. 4 pts cancelled before starting treatment and were excluded from analyses. This interim report includes the first 104 pts for which at least one post-baseline evaluation was available. Baseline characteristics were well-balanced between the arms. Sixty-two percent were on tamoxifen or an aromatase inhibitor for the duration of the study. Pts on both Oxy doses had a significantly greater reduction in HF score and frequency compared to P. Pts on Oxy2.5 had a mean change in HF score of -10 (SD 7.4) vs -5.1 (SD 9.7) with P, p=0.003; and a mean change in average weekly number of HF of -4.6 (SD 3.1) vs -2.3 (SD 3.9), p=0.002. Pts on Oxy5 had a mean change in HF score of -16.2 (SD 5.1) vs -5.1 (SD 9.7) with P, p<0.001; and a mean change in average weekly number of HF of -7.0 (SD 4.0) vs -2.3 (SD 3.9), p<0.001. Repeated measures mixed models confirmed that, after adjusting for baseline values, both Oxy arms had significantly lower HF scores and frequency compared to P (p<0.001). HFRDIS revealed that pts in both Oxy arms experienced improvement in the following HF interference measures: work, social activities, leisure activities, sleep, relations, life enjoyment, and overall quality of life. Pts on Oxy5 also had improvement in HF interference with mood. Pts on Oxy2.5 experienced more stomach pain (p=0.031), diarrhea (p=0.007), nausea (p=0.04), headaches (0.032), episodes of confusion (0.012), dry mouth (p=0.003) and dry eyes (0.027) compared to P. Pts on Oxy5 experienced more constipation (0.004), dry mouth (0.001) and difficulty urinating (0.004) compared to P. There were no differences in study discontinuation due to adverse effects between either Oxy arm and P (Oxy2.5 vs P, p=0.653; Oxy5 vs P, p=0.483). Conclusions: Oxy is superior to P for management of HF. Oxy2.5 and 5 were both associated with significant improvements in HF scores and frequency as well as improvement in HF interference with several quality of life measures. While pts on Oxy experienced more side effects than pts on P, rates of discontinuation due to adverse events were low. This study was supported by the Breast Cancer Research Foundation. Citation Format: Leon-Ferre RA, Novotny PJ, Faubion SS, Ruddy KJ, Flora D, Dakhil C, Rowland KM, Graham ML, Le-Lindqwister N, Loprinzi CL. A randomized, double-blind, placebo-controlled trial of oxybutynin (Oxy) for hot flashes (HF): ACCRU study SC-1603 [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 GS6-02.

Abstract Background: Aromatase inhibitors are a mainstay hormone receptor-positive breast cancer treatment. AIA occur in up to 50% of patients (pts), adversely affecting quality of life and treatment compliance. A small phase II clinical trial of oral testosterone unedeconate appeared to improve AIA over placebo (P), with no significant androgenic side effects. The current study was performed to confirm these findings. Methods: This randomized P-controlled trial enrolled postmenopausal women on adjuvant anastrozole or letrozole and experiencing moderate-to-severe AIA (≥5 on 0-10 scale). Pts were initially randomized to receive a subcutaneous pellet containing T 120 mg + anastrozole 8 mg (T+AIpellet) or P at the end of the first week on study (after obtaining baseline hot flash data) and at 3 months (mo). Due to slow accrual, the protocol was amended to change the route of delivery to topical T or P applied to the skin once daily for 6 mo. Baseline and monthly questionnaires were administered, including: Modified Brief Pain Inventory for aromatase arthralgia (BPI-AIA), prolife of mood states (POMS), the menopause specific quality of life questionnaire (MENQOL), a hot flash diary, the hot flash related daily interference scale (HFRDIS) and a symptom experience questionnaire. The primary endpoint was intra-patient change in joint pain at 3 mo, compared using a two-sample t-test. Results: 227 pts were accrued between 9/1/2013-11/29/2017. 55 pts were randomized prior to the protocol amendment and received T+AIpellet or P. Baseline characteristics were balanced between arms, with the exceptions of median weight, BMI, hemoglobin (all higher in T arm), and breast tenderness, dissatisfaction with personal life/depression, and skin changes (all higher in P arm). Compared to baseline, there were no significant differences between T and P in average pain or joint stiffness at 3 (p=0.483) or 6 mo (p=0.573). Average pain was significantly lower each month compared to baseline, irrespective of treatment arm. There were no significant differences in any other items evaluated by BPI-AIA, POMS, MENQOL, hot flash diary or HFRDIS. Similarly, there were no substantial differences in toxicity. A subset analysis of the 55 pts randomized to receive T+AIpellet or P identified significant reductions in average pain scores with T+AIpellet during the first month (p=0.038), but not thereafter. T+AIpellet pts had significantly more reduction in reported % of baseline hot flash frequency (p=0.034) and score (p=0.031), nausea (p=0.019), fatigue (p=0.042), mood swings (p=0.026), hand/feet swelling (p=0.009), stress urinary incontinence (p=0.039) and changes in appearance, texture or tone of their skin (p=0.0083), than pts on P. Conclusions: Overall, T did not improve AIA or menopausal symptoms compared to P. While there was significant improvement in AIA over the study period, T did not facilitate this process. However, T+AIpellet was associated with improvement in short-term AIA and several menopausal symptoms compared to P, suggesting that subcutaneous T combined with anastrozole may be superior to transdermal T alone. Support: UG1CA189823, U10CA180820, U10CA189809; ClinicalTrials.gov Identifier: NCT01573442 Citation Format: Leon-Ferre RA, Le-Rademacher J, Terstriep S, Glaser R, Novotni P, Giuliano A, Copur MS, Jones C, Page S, Mitchell W, Birrell SN, Loprinzi CL. A randomized, double-blind, placebo-controlled trial of testosterone (T) for aromatase inhibitor-induced arthralgias (AIA) in postmenopausal women: Alliance A221102 [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 P4-16-01.

Abstract Background: Breast cancer care imposes a significant financial burden to U.S. healthcare systems and has become a key focus in the health care debate. Therapies for breast cancer are expensive, and the economic burden of these therapies may be rising due to the rapid introduction of pricey new drugs and techniques. There are limited data on the health care costs of individuals with breast cancer after initial diagnosis and how these costs have changed over time. Methods: We conducted a retrospective analysis of commercially insured adult women with newly diagnosed non-metastatic breast cancer (identified via previously published claims-based algorithms) using 2007-2016 data from a large US health plan available in OptumLabs® Data Warehouse. We included patients with continuous health plan coverage for at least 2 years after initial diagnosis 2007-2014 and assessed how total health care spending and out-of-pocket costs (paid amounts) changed over this time. Costs were adjusted to 2016 US dollars using the general Consumer Price Index. Inpatient, outpatient, and outpatient pharmacy costs were evaluated. A multivariable logistic regression model was used to examine predictors of above average cost (cost > mean for that year of diagnosis). Results: A total of 12,446 newly diagnosed breast cancer patients were identified (mean age, 51.6 years). Forty percent had undergone mastectomy, 38% chemotherapy, and 63% radiation. After adjustment for inflation, total healthcare costs increased 29.7% from 2007 to 2014 (Table 1), with increases primarily observed during the first year after diagnosis. Out-of-pocket costs remained relatively stable, and accounted for 5.3% of the total spending. Approximately 80% of the total costs were related to care received in the outpatient setting. Factors independently associated with above average spending included treatment with mastectomy [OR 1.78 (95% CI 1.5-2.1)], reconstruction [OR 3.0 (95% CI 2.6-3.5)], radiation [OR 4.0 (95% CI 3.4-4.7)] and chemotherapy [OR 18.4 (95% CI 16.6-20.3]. Table 1.Average healthcare spending over time Mean cost during first year after diagnosisMean cost during second year after diagnosisYear of diagnosistotalout-of-pockettotalout-of-pocket2007$80,296.17$4,271.25$16,559.21$1,907.012008$84,126.70$4,445.78$16,785.43$2,205.982009$88,331.45$4,728.42$17,005.68$2,214.932010$91,502.58$5,067.78$17,243.91$2,126.192011$93,826.40$5,089.45$16,862.45$2,027.962012$96,690.06$5,449.91$17,814.09$2,179.262013$104,064.93$5,678.19$17,087.47$2,115.972014$104,169.74$5,620.51$16,714.12$1,590.67 Conclusions: Breast cancer care is increasingly expensive during the first year after diagnosis, and costs are greatest for the recipients of more aggressive treatments. Costs during the second year after diagnosis have remained relatively stable. Citation Format: Ruddy KJ, Sangaralingham LR, Freedman RA, Jemal A, Mougalian SS, Keegan T, Loprinzi CL, Gross CP, Henk HJ, Shah N. Trends in the cost of care for breast cancer among women with commercial insurance [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 PD6-07.

Abstract Purpose: Prevention of chemotherapy-induced nausea and vomiting (CINV) is essential to preserve quality of life in cancer patients receiving highly emetogenic chemotherapy (HEC) such as doxorubicin-cyclophosphamide (AC) or cisplatin. Recently, new drugs (e.g. fosaprepitant and newer neurokinin 1 receptor antagonists [NK1RAs], rolapitant and netupitant) and updated guidelines for antiemetic use (e.g. adding olanzapine) have emerged. However, trends in real world antiemetic use are understudied. Methods: We performed a retrospective study using the OptumLabs Data Warehouse (OLDW), which includes administrative claims for privately insured and Medicare Advantage enrollees in the U.S. We identified 34,236 patients age 18 years or older treated with either AC or cisplatin between January 2006 and June 2016. Data collected included baseline demographics (age, gender, census region and race), chemotherapy administered, and presence/absence of a central intravenous access device. Trends of anti-emetic use were presented overall and separately for 5-HT receptor antagonists (5HT3RAs) and NK1RAs. Results: 23,030 patients (67.3%) received an anthracycline-based regimen (AC with or without docetaxel or paclitaxel), and 11,206 (32.7%) patients received cisplatin. Approximately two thirds of patients were female (n= 23,392). Dexamethasone use was stable over the decade (used by 85-90% in all years). Use of 5HT3RAs, primarily palonosetron and ondansetron, occurred in at least 95% of patients in all study years, consistent with guideline recommendations. NK1RAs were underutilized early on compared with guideline recommendations, but use increased to approximately 80% in the most recently evaluated year. Fosaprepitant use rose precipitously starting in 2009, preceding a sharp fall in aprepitant use beginning in 2011. The use of olanzapine, rolapitant and netupitant was minimal throughout the study period. Conclusions: Dexamethasone and 5-HT3RAs were used in the vast majority of patients receiving HEC, in accordance with guideline recommendations. Less compliance with guidelines was seen with NK1RA use. Citation Format: O'Sullivan CC, Van Houten HK, Sangaralingham L, Leal AD, Shinde S, Liu H, Ettinger D, Loprinzi CL, Ruddy KJ. Ten year trends in antiemetic prescribing in cancer patients receiving highly emetogenic chemotherapy (HEC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-11-18.

Abstract Background Activating mutations in PIK3CA occur in approximately 40% ER+BC. MK-2206 (M), a pan-AKT inhibitor, induced apoptosis of ER+ BC under estrogen deprivation in preclinical studies. We conducted this neoadjuvant trial to determine the pathologic complete response (pCR) rate of M plus anastrozole (A) for PIK3CA mutant (Mut) ER+ BC. Methods This single arm open label study of M+A used a 2-stage Simon phase II design (stage 1, n=16; stage 2, n=13, alpha=0.10, power=0.90) to test whether pCR rate <1% (based on historical data with A alone), against the alternative that pCR rate ≥15% in PIK3CA Mut ER+ BC. At least 1 pCR in stage 1 was required to proceed to stage 2. Eligible patients (pts) with clinical stage II or III ER+HER2- BC were pre-registered and proceeded to a research tumor biopsy for PIK3CA sequencing, followed by treatment with daily A monotherapy for 28 days (cycle 0). Pts with PIK3CA Mut BC were subsequently registered, underwent a second biopsy, and started M (150mg PO weekly) with daily A on cycle 1 day 1 (C1D1) for a maximum of four 28-day cycles followed by surgery. Goserelin was added for premenopausal pts. A tumor biopsy on C1D17, 17 days post the start of M, was performed. Those with C1D17 Ki67 >10% discontinued study treatment. pCR was defined as no invasive cancer in the breast and the lymph nodes. Tumor specimens collected at all timepoints are being analyzed for markers of proliferation, apoptosis, and PI3K pathway activity, gene expression microarray, intrinsic subtypes, and next generation sequencing of 83 genes. Results Of the 51 pts pre-registered, 35 pts did not register due to no PIK3CA mutation (n=22), inadequate specimen for testing (n=6), physician/pt decision (n=7). The remaining 16 pts (median age: 58, range: 40-77 years) received combination therapy. Three pts did not complete 4 cycles due to C1D17 Ki67 >10% (n=2) and intolerability (grade (Gr) 4 transaminase elevation in C1, n=1). Other severe toxicities possibly related to M included Gr 3 rash (25%) and pruritus (12.5%). Of the 13 pts completed study therapy and underwent surgery, all had residual disease in the breast and 7 also had positive nodes. Table 1 summarized changes in Ki67 during treatment. ComparisonsnAbsolute changes in Ki67 median (range)Wilcoxon signed rank p-valueC1D1 relative to pre-registration11-17.0% (-49.8 to 4.1%)0.0020C1D17 relative to pre-registration14-16.4% (-51.4 to 4.1%)0.0004C1D17 relative to C1D112-1.5% (-18.6 to 15.8%)0.9697C1D1, biopsy post 28 days of A alone; C1D17 biopsy post 17 days on combination therapy Although Ki67 levels post A monotherapy (C1D1) or M+A (C1D17) were significantly lower than that of pre-registration samples, Ki67 did not differ between C1D17 and C1D1 samples. Other correlative studies are ongoing and results will be presented. Conclusion Despite the small sample size, biomarker analysis on serial biopsy specimens demonstrated that M+A is unlikely to be more effective than A alone in PIK3CA Mut ER+ BC. This trial demonstrated the feasibility of genomic sequencing for pt selection and the value of a small, well-designed proof-of-principle neoadjuvant trial for the evaluation of targeted agents. Citation Format: Ma CX, Suman VJ, Goetz M, Northfelt D, Burkard M, Ademuyiwa F, Naughton M, Margenthaler J, Aft R, Gray R, Tavaarwerk A, Wilke L, Haddad T, Moynihan T, Loprinzi C, Hieken T, Hoog J, Guo Z, Han J, Vij K, Mardis E, Sanati S, Al-Kateb H, Doyle L, Erlichman C, Ellis MJ. A phase II neoadjuvant trial of MK-2206, an AKT inhibitor, in combination with anastrozole for clinical stage 2 or 3 PIK3CA mutant estrogen receptor positive HER2 negative (ER+HER2-) breast cancer (BC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-13-04.