Abstract OT1-01-05: Endocrine treatment alone as primary treatment for elderly patients with estrogen receptor positive good prognosis operable breast cancer: A single arm phase II, single institution study

Background: It is estimated that approximately 46,000 women age >75 are diagnosed annually with breast cancer. Due to competing co-morbidities, there is wide variation in treatment recommendations which can lead to over- or under-treatment. Though surgery for breast cancer is considered low-morbidity, many elderly women given a choice, choose not to have surgery. Previous randomized trials comparing surgery with tamoxifen versus endocrine therapy alone in women age >70 unselected for ER status demonstrated similar overall survival with poorer local control in the latter group. A new standard of care needs to be defined for elderly women with good prognosis ER+ tumors, since these women may benefit from endocrine therapy alone to treat their cancer without compromising local and distant control.

Hypothesis: We hypothesize that endocrine therapy alone provides adequate local and systemic control of breast cancer in a subpopulation of women age 70 or older with ER+ breast cancer and good prognostic characteristics.

Primary Objective

To correlate response to neoadjuvant endocrine treatment at 6 months with Oncotype DX Recurrence Score (RS) in women with early-stage ER+ breast cancer who are age >70.

Secondary Objective

1. To determine the breast cancer-specific survival of women with early-stage ER+ breast cancer, age >70, treated with endocrine therapy alone.

2. To determine the rate of overall survival of women with early-stage ER+ breast cancer, age >70 treated with endocrine therapy alone.

Study Design: This is a prospective single arm phase II study. Patients with clinical stage I/II ER+ breast cancer, grade 1-2, Ki67<30 or RS <18 (performed on the diagnostic core biopsy) continue to be enrolled and followed for time to progression. A Kaplan-Meier model will be used to estimate the 5-year local progression rate. If the true 5-year progression rate is 10%, then 50 patients will provide power = .90 at a one-sided .05 significance level to demonstrate that the rate is less than 25.5%. Exploratory objectives include: evaluation of the molecular characteristics of breast cancers of responders versus non-responders, determine compliance with medications, evaluate cost-effectiveness, and quality of life.

Results: Between February 2017 and April 2018, 11 patients were enrolled into the study. Two patients could not tolerate endocrine therapy and received standard of care treatment. For the 9 patients on study, average tumor size was 1.7cm, average Ki67 was 15%, average RS was 14. All of the patients received an aromatase inhibitor. At 6 months, 71% of the patients had a partial response, 28% had stable disease. None of the patients developed progressive disease.

Conclusion: A new standard of care needs to be defined for women age >70 with good prognosis ER+ tumors, since these women may benefit from endocrine therapy alone to treat their cancer without compromising local and distant control. We continue to enroll patients to determine the optimal tumor markers for identifying women who can be treated with PET only to control their cancer.

Citation Format: Aft R, Cherian M, Frith A, Suresh R, Glover-Collins K, Naughton M, Moon C, Conant L, Ma C. Endocrine treatment alone as primary treatment for elderly patients with estrogen receptor positive good prognosis operable breast cancer: A single arm phase II, 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 OT1-01-05.

Abstract PD6-02: A randomized, controlled trial of high dose vs. standard dose vitamin D for aromatase inhibitor-induced arthralgia in breast cancer survivors

Background: Approximately half of women on aromatase inihbitor (AI) therapy develop AI-induced arthralgia (AIA), and many discontinue the medication because of this common side effect. While Vitamin D has been studied as a treatment for AIA, trial results have been conflicting thus far.

Patients and Methods: All subjects were post menopausal women who were beginning adjuvant AI therapy for stage I-III hormone receptor positive breast cancer. Patients were randomized 1:1 to receive standard dose vitamin D3 (800 IU daily for 52 weeks) or high dose vitamin D3 (50,000 IU weekly for 12 weeks, followed by 2000 IU daily for 40 weeks). All patients also took oral calcium 600 mg daily. The primary endpoint was development of AIA, as defined by pre-specified changes in the Health Assessment Questionnaire II (HAQ-II). Secondary endpoints include compliance with AI therapy, and correlation between grip strength and development of AIA. Exploratory endpoint was measurement of inflammatory cytokine reduction in each arm. The trial was designed to enroll 184 patients, but this futility analysis was performed after 93 patients were enrolled. The futility boundary for stopping the trial early was calculated as p = 0.47.

Results: All 93 patients (46 in the high dose arm, and 47 in the standard dose arm) enrolled in the study at the time of the interim analysis were evaluable. The HAQ-II was completed at 12 weeks in 76% on the high dose arm, and 68% in the standard dose arm. Subjects who did not complete the questionnaire were deemed as study failures (i.e. development of AIA was assumed). In the high dose arm, 25 patients (54%) developed AIA, compared to 27 patients (57%) in the standard dose arm. The one-tailed p value is 0.3818, and the Z-score is 0.3, yielding only a 38% conditional power that that study would find a significant difference between the two arms. Thus, the study was terminated early for futility. There was no significant difference between the two arms in adherence to AI therapy. The grip strength and inflammatory cytokine data are pending at this time. They will be ready by the time of the conference.

Conclusions: There was no significant signal for benefit of high dose vitamin D supplementation, as compared to standard dose vitamin D, for AIA prevention in post menopausal women taking adjuvant AI therapy. These results further characterize the role of Vitamin D in AIA, and they inform future clinical trials in this arena. Further research is necessary, as this remains an important cause of non-adherence to this highly effective therapy.

Citation Format: Niravath P, Wang T, Hilsenbeck SG, Lipscomb K, Pavlick A, Jiralerspong S, Nangia J, Ellis M, Ademuyiwa F, Cherian M, Frith A, Ma C, Park H, Rigden C, Suresh R, Osborne CK, Rimawi MF. A randomized, controlled trial of high dose vs. standard dose vitamin D for aromatase inhibitor-induced arthralgia in breast cancer survivors [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 PD6-02.

Abstract P5-21-30: Retrospective review of palbociclib (Pal) efficacy and benefit from subsequent treatments following Pal progression in patients (pts) with hormone receptor positive (HR+) and HER2 negative (HER2-) metastatic breast cancer (MBC)

Background

The cyclin-dependent kinase (CDK) 4/6 inhibitor Pal is approved for HR+ HER2- MBC. However, the optimal therapy following Pal progression is unknown. Therefore we conducted this retrospective study to review Pal efficacy and summarize the practice pattern and responses to subsequent treatments post Pal progression.

Methods

We performed a chart review of pts with HR+ HER2- MBC who began Pal treatment at Washington University Siteman Cancer Center between Feb 16, 2015 and July 13, 2016 and collected information on pts demographics, diagnosis, and treatment history. Duration of therapy was used to calculate the progression free survival (PFS) for each regimen. Treatment was considered first-line if administered without any prior systemic therapy or at least 1 year from completion of adjuvant hormonal therapy (HT). Treatments received after progression on 1st line therapy or upon relapse during or within 1 year from the completion of adjuvant HT were considered second-line regimens.

Statistical analyses were performed on SAS software, version 9.4. The Kaplan-Meier method was used to generate time-to-event curves, from which median PFS was calculated. A stratified log-rank test was used for all comparisons, and the P value derived from the comparison was reported.

Results

We completed a chart review for 81 pts (78 female and 3 male; 63 Caucasian, 14 African American, and 4 other races) with HR+ HER2- MBC (68 were ER+PR+, 13 were ER+PR-) who received Pal plus letrozole (n=65) or fulvestrant (n=15) or anastrozole (n=1), with a median age of 62.0 years (range 28.1 - 85.6) at the start of Pal.

The median follow up was 20.0 months (mos) (range 10.8 – 27.9). 25 pts were still on Pal treatment. The median PFS on Pal was 19.9 mos in the first-line setting (n=20), compared to 12.1 mos and 4.4 mos in the second-line (n=14) and subsequent lines (n=47), respectively (p=0.0287). Among the 54 pts who progressed on Pal, 38 moved on to the next treatment. 20 pts received chemotherapy and 16 pts received HT or a HT combination. 2 pts received fulvestrant plus Pal upon progression on letrozole plus Pal, and treatment was still ongoing at 4 mos and 7 mos of follow up, respectively. The most common treatments post Pal were single-agent capecitabine (Cape) (n=9) and the combination of exemestane (Exe) and everolimus (Eve) (n=8). The median PFS was 4.7 mos with Cape compared to 8.4 mos with Exe and Eve (p=0.60). The median PFS was 4.7 mos for the 20 pts who received chemo, whereas the median PFS was 4.9 mos with subsequent HT (n=16) (p=0.75).

Conclusion

Pal plus letrozole or fulvestrant is effective for the treatment of HR+ HER2- MBC, with activity observed beyond the 1st and 2nd line treatment settings. The PFS of Pal observed in this single center retrospective study is consistent with that of published data. Single-agent cape or the Exe and Eve combination were common treatment choices following progression on Pal. Although the study is limited by its small sample size, the median PFS of 8.4 mos with Exe and Eve indicates its potential efficacy in the setting of Pal progression. Additional pts and followup data will be presented.

Citation Format: Xi J, Oza A, Thomas S, Naughton M, Ademuyiwa F, Weilbaecher KN, Suresh R, Bose R, Cherian MA, Hernandez-Aya L, Frith A, Peterson LL, Krishnamurthy J, Ma CX. Retrospective review of palbociclib (Pal) efficacy and benefit from subsequent treatments following Pal progression in patients (pts) with hormone receptor positive (HR+) and HER2 negative (HER2-) metastatic breast cancer (MBC) [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 P5-21-30.

Incidence of migraine relative to menstrual cycle phases of rising and falling estrogen

OBJECTIVE

To investigate the association between urinary hormone levels and migraine, with particular reference to rising and falling levels of estrogen across the menstrual cycle in women with menstrual and menstrually related migraine.

METHODS

Women with regular menstrual cycles, who were not using hormonal contraception or treatments and who experienced between one and four migraine attacks per month, one of which regularly occurred on or between days 1 +/- 2 of menstruation, were studied for three cycles. Women used a fertility monitor to identify ovulation, conducting a test each day as requested by the monitor, using a sample of early morning urine. Urine samples were collected daily for assay of estrone-3-glucuronide, pregnanediol 3-glucuronide, follicle-stimulating hormone, and luteinizing hormone. All women kept a daily migraine diary and continued their usual treatment for migraine.

RESULTS

Of 40 women recruited, data from 38 women were available for analysis. Compared with the expected number of attacks, there was a significantly higher number of migraine attacks during the late luteal/early follicular phase of falling estrogen and lower number of attacks during rising phases of estrogen.

CONCLUSION

These findings confirm a relationship between migraine and changing levels of estrogen, supporting the hypothesis of perimenstrual but not postovulatory estrogen "withdrawal" migraine. In addition, rising levels of estrogen appear to offer some protection against migraine.

Prevention of menstrual attacks of migraine: A double-blind placebo-controlled crossover study

OBJECTIVE

To assess the effect of perimenstrual estradiol supplements on menstrual attacks of migraine associated with estrogen withdrawal.

METHODS

Women with regular menstrual cycles and menstrual migraine or menstrually related migraine completed an initial three-cycle assessment confirming eligibility for a six-cycle crossover study using estradiol or placebo to prevent menstrual attacks of migraine. Women collected early morning samples of urine daily for laboratory assay and used a fertility monitor to identify peak fertility associated with ovulation. Estradiol gel or placebo was first applied on the tenth day following the first day of peak fertility and continued daily until, and including, the second full day of menstruation. Women kept a daily migraine diary and continued their usual treatment for migraine. The main outcome was the number of days during gel use on which a migraine occurred.

RESULTS

Data from 35 women were available for a paired analysis. Percutaneous estradiol was associated with a 22% reduction in migraine days (RR 0.78, 95% CI 0.62 to 0.99, p = 0.04); these migraines were less severe and less likely to be associated with nausea. This was, however, followed by a 40% increase in migraine in the 5 days following estradiol vs placebo (RR 1.40, 95% CI 1.03 to 1.92, p = 0.03).

CONCLUSION

Although perimenstrual percutaneous estradiol showed benefit during treatment, this was offset by deferred estrogen withdrawal, triggering post-dosing migraine immediately after the gel was stopped. Further work could assess if this could be avoided by extending the duration of treatment with estradiol.