Citations

11534 Background: To date, there are no validated blood-based biomarkers of predicting response to PD-1 blockade. We previously reported that Bim is a downstream signaling molecule of the PD-1 pathway, and that measurement of Bim levels in circulating T-cells may predict and monitor responses to anti–PD-1 therapy in melanoma. We have identified the existence of sPD-L1 in cancer patients and showed that the sPD-L1 is biologically active and capable of triggering apoptosis in activated T-cells. Here we evaluated T cell Bim and sPD-L1 in the peripheral blood (PB) as biomarkers of response in a cohort of patients with metastatic melanoma and lung cancer undergoing anti-PD1 therapy. Methods: 60 pts treated with anti-PD-1 had PB collected at baseline and at radiographic tumor evaluation. Frequencies of Bim+ T cells and Bim median fluorescence intensity (MFI) were measured by flow cytometry in gated tumor-reactive CD11ahighPD1+ CD8+ T cells. We also measured levels of sPD-L1 at baseline and serially during treatment with sPD-L1 ELISA. Baseline Bim and sPD-L1 levels and percent change in Bim levels in patients (pts) who had a radiographic response (CR/PR) were compared to those who had progressive disease (PD) at 12 wks. Results: Similarly to previously reported preliminary data, pts with objective response (CR/PR, 15/60) after 4 cycles of anti-PD1 therapy had higher frequency of Bim T cells at baseline compared to pts with PD (16/60) (mean 43% vs. 30%, P = 0.0484). The frequencies of Bim+ T cells decreased significantly after the first 3 months of treatment in responders compared with progressors (mean -16% vs. + 40% P = 0.0111). High baseline sPD-L1 were associated with progression on anti-PD1 therapy (mean 2.8 ng/mL vs. 0.7 ng/mL, p = 0.07, n = 13) and the levels increased by the first tumor assessment in patients resistant to anti-PD-1. Conclusions: Measurements of Bim and sPD-L1 levels may help to select patients who are likely to benefit from anti-PD1 monotherapy versus combinatorial strategies, and provide a new non-invasive way to monitor response to anti-PD-1 blockade. A larger validation study is underway.

10065 Background: Prospective data regarding fertility and pregnancy after breast cancer are limited. Many young survivors are interested future fertility, but pregnancy rates among women attempting and not attempting pregnancy have not been studied prospectively. Methods: As part of a multicenter cohort study, women diagnosed age ≤40 with stage 0-3 breast cancer are surveyed at baseline then annually regarding fertility interest, attempts, and pregnancies. Chi-square tests were used to compare proportions attempting and achieving pregnancy. Results: At least once in the 5 years (yrs) after Dx, 334/959 (35%) women reported interest in future biologic children. The percent interested was stable in the first 3 yrs then declined: 256 (27%, baseline), 244 (27%, 1 year), 209 (25%, 2 yrs), 176 (25%, 3 yrs), 106 (18%, 4 yrs), and 72 (16%, 5 yrs). Pregnancy was attempted by 104/334 (31%) of women who reported interest and 4/625 (1%) who did not. Pregnancy occurred in 118 women (12%), including 76/108 (70%) who attempted and 42/851 (5%) who did not. Attempts and achieving pregnancy were associated with younger age, partnered status, and not having children prior to Dx (table). Lower stage was associated with attempting pregnancy and ER negative disease with achieving pregnancy. Conclusions: A substantial number of young women become pregnant in the 5 years after a breast cancer diagnosis. Given that over 1/3 of pregnancies were among women who did not report attempting, additional attention to contraception counseling should be considered. Further evaluation of assisted reproductive technology use, pregnancy and disease outcomes in this cohort, and the POSITIVE Trial (NCT02308085) will shed light on the feasibility and safety of pregnancy after breast cancer. [Table: see text]

e20092 Background: More than 5,000 premenopausal women are diagnosed (dx’d) with lung cancer annually in the United States. Improvements in treatment are contributing to a growing population of young survivors. Limited data exist regarding the risk of treatment-related amenorrhea, a surrogate for infertility and early menopause, after systemic therapies for lung cancer. Methods: Since 1997, we mailed annual surveys to patients seen at Mayo Clinic for lung cancer who consented to join a research cohort. Surveys queried menopausal status and age of menopause. Those who were dx’d under age 50, who were treated with curative intent, and who reported that they were premenopausal at the time of the cancer dx were included in this analysis. “Immediate” treatment-related menopause was defined as reporting age of menopause as the same as the age at diagnosis or 1 year (yr) older. Results: Of 182 survey respondents to date (mean time from dx to 1st survey: 26 mos, SD 24 mos, range 12-202 mos), 85 (mean age 44 yrs, SD 5, range 34-48) received chemo during the yr after diagnosis, 26 of whom also received targeted therapy during that yr. Lung cancer dx occurred 1958-2016. Platinum drugs, taxanes, and etoposide were the most common chemotherapies. 46% of chemo recipients (mean age 47, SD 2, range 41-49) experienced immediate menopause, 9% (mean age 43 yrs, SD 5, range 35-48) experienced menopause at least 2 yrs after the age of dx, and 45% (mean age 40 yrs, SD 5, range 25-48) remained pre- or peri-menopausal at their final survey (on average 3 years after dx, SD 2, range 1-10). Only 3 patients received targeted therapy alone, and the remaining 94 (mean age 42 yrs, SD 6 years) received no systemic therapy within a year of diagnosis. 15% of these 94 (mean age 45 yrs, SD 3, range 41-49) experienced immediate menopause, 16% (mean age 43 yrs, SD 4, range 36-49) experienced menopause 2+ yrs after the age of diagnosis, and 69% (mean age 41 yrs, SD 7, range 20-49) remained pre- or perimenopausal at their final survey (on average 4 yrs after dx, SD 3, range 1-10). Conclusions: Chemotherapy for lung cancer causes amenorrhea in a substantial proportion of women dx’d with lung cancer while premenopausal. Further research on fertility and menopausal symptoms after lung cancer treatment, and on differences between regimens, is warranted.

TPS8053 Background: The advent of proteasome inhibitors and immunomodulatory drugs (IMiDs) have significantly improved outcomes in MM, and the first monoclonal antibodies for MM have been recently approved (daratumumab, elotuzumab). Despite novel therapies and improved disease management, MM is still considered incurable and most pts relapse, confirming the need for additional treatment options. MM cells express PD-L1, with higher levels observed after relapse and with advanced disease. Additionally, PD-L1–expressing immune cells in the microenvironment promote MM cell survival and potential immune escape. However, anti–PD-1 monotherapy did not result in objective responses in the MM cohort of a Ph I study, suggesting that MM pts need combination therapy. Daratumumab has activity as a single agent, as well as in combination with IMiDs plus dexamethasone and bortezomib plus dexamethasone in R/R MM. Immunomodulatory activity for daratumumab has also been reported. Thus, disruption of the PD-L1/PD-1 pathway may be additive or synergistic. The safety and efficacy of atezo (anti–PD-L1) alone or with lenalidomide or pomalidomide and/or daratumumab will be evaluated in a Ph Ib study of MM pts. NCT02431208. Methods: R/R MM pts with ≤ 3 prior therapies will be enrolled in Cohorts A (atezo), B (atezo + lenalidomide), D (atezo + daratumumab) and E (atezo + daratumumab + lenalidomide); MM pts with measurable disease after ASCT (Cohort C: atezo) or ≥ 3 prior therapies (Cohort F: atezo + daratumumab + pomalidomide) will also be enrolled. Cohorts B, D, E and F include a safety run-in (D) or dose escalation phase (B, E, F) and an expansion. Lenalidomide and pomalidomide will be dose escalated and the MTD evaluated in expansion phases. Atezo will be given at 1200 mg IV (A, B, C) or 840 mg IV (D, E, F); pts will get daratumumab at 16 mg/kg IV (D, E, F). All pts will be ECOG PS ≤ 2. Primary endpoints are ORR and the RP2D of lenalidomide and pomalidomide with atezo and daratumumab and the RP2D of lenalidomide with atezo. DOR and PFS are secondary endpoints; safety, PK and the relationship between biomarkers and other endpoints, including efficacy, will be assessed. Pts will be enrolled at 19 US sites. Clinical trial information: NCT02431208.

6520 Background: Breast cancer follow-up guidelines recommend imaging for distant metastases only in the presence of signs/symptoms. However, data supporting this recommendation predates the current era of improved imaging and targeted therapies based on molecular subtype. The objective was to assess the relationship between mode of distant recurrence detection and survival. Methods: A stage-stratified random sample of Stage II-III breast cancer patients diagnosed in 2006-7 was selected from NCDB records from 1,217 CoC-accredited facilities (10/hospital n = 10,853). Women were categorized by subtype: 1) ER or PR+/HER2-; 2) ER and PR-/Her2- (triple negative); 3) HER2+. Medical records abstracted for 5-years post-surgery supplemented NCDB data and assessed distant recurrence and mode of detection (prompted by signs/symptoms or surveillance imaging), imaging (chest CT, abdomen/pelvis CT/MRI, head CT/MRI, bone scan, PET/CT), death date. The relationship between mode of recurrence detection and days from initial cancer diagnosis to death was assessed using propensity-weighted multivariable Cox proportional hazards regression stratified by subtype. Propensity weights, based on receipt of surveillance systemic imaging, accounted for sociodemographic and tumor/treatment factors. Results: 5-year distant recurrence was 22.3% for triple negative, 14.8% HER2+, and 11.2% for ER or PR+/ HER2- patients. Asymptomatic imaging detected recurrence in 22.9% and signs/symptoms in 77.1%. Patients with asymptomatic as compared to sign/symptom detected recurrences had reduced risk of death in 5 years if triple negative (HR = 0.68, 95% CI = 0.50-0.93) or HER2+ (HR = 0.40, 95% CI = 0.24-0.65) with no significant association for ER or PR+/HER2- (HR = 1.2, 95% CI = 0.88-1.51). This translated to a between-group difference in weighted median survival of 5 months for triple negative and 13 months for HER2+ patients. Conclusions: This is the first nationally representative study to show a survival advantage with asymptomatic detection of distant metastases for patients, with the benefit limited to triple negative and HER2+ disease. Further research to confirm observational findings is warranted.

e15641 Background: CC pts with biliary stents or catheters are prone to have obstruction/infection and studies show 20-40% present with fever/or jaundice requiring urgent treatment for which there is no uniform guideline. We aimed to develop an expert panel consensus on this topic using the modified RAND/UCLA Delphi process to rate treatment appropriateness. Methods: We recruited 13 physician experts from relevant specialty, geography, and practice settings. Patient scenarios were developed and panelists rated the therapies before and after a face-to-face discussion. The appropriateness of various therapies was rated on a 1-9 scale and classified as appropriate, inappropriate, or uncertain. Scenarios with > 2 ratings of 1-3 (inappropriate) and > 2 ratings of 7-9 (appropriate) were considered to have disagreement and were not assigned an appropriateness rating. Results: Panelists were from all US regions (92%) and the UK (8%); had practiced for a mean 16.5 years (4-33 years). Panelists rated 480 scenarios before the meeting, but re-rated only 288 clinical scenarios as they felt that ongoing treatment with chemotherapy did not influence decision-making. Disagreement decreased from 37.5% before the meeting to 10.4% after. Consensus statements are summarized in the table below. Conclusions: The Delphi process produced consensus guidelines to fill an unmet need in urgent management of ascending cholangitis in pts with CC. (Support: The Cholangiocarcinoma Foundation). [Table: see text]