Abstract P2-09-03: Updated efficacy of first or second-line pembrolizumab (pembro) plus capecitabine (cape) in metastatic triple negative breast cancer (mTNBC) and correlations with baseline lymphocyte and naïve CD4+ T-cell count

Background: In mTNBC, anti-PD-1/L1 monotherapy is most effective when administered early in the course of disease, with recent trials demonstrating overall response rates (ORR) of 23-26% in the first-line setting and 5-6% in later lines. This may reflect iatrogenic lymphopenia from preceding cytotoxic chemotherapy. Furthermore, curative-intent chemotherapy is associated with prolonged suppression of naïve CD4+ cells, a T-cell subset that may play a critical role in the generation of de novo anti-tumor immune responses. We present the final clinical results of a pilot study evaluating the safety and efficacy of combining pembrolizumab plus standard-of-care capecitabine in the first/second-line mTNBC setting. We also explore potential associations between clinical benefit and lymphopenia, preceding chemotherapy, and absolute naïve CD4+ counts.

Methods: In a pilot study, we evaluated the tolerability and preliminary efficacy of concurrent pembro (200mg IV q21 day) plus investigator-selected 1st/2nd line paclitaxel (80mg/m2 IV weekly) or oral cape (2,000mg BID, weekly 1 on/1 off). The primary endpoint was tolerability, defined as the proportion of subjects receiving >6 weeks concurrent therapy without dose discontinuation with toxicities reported per CTCAE v4.0. The secondary endpoint was 12-week objective response rate (ORR) by RECIST1.1. Exploratory endpoints included peripheral blood cell enumeration by real-time flow cytometry and routine clinical laboratory. Naïve CD4+ cells were defined as CD45+ CD3+ TCRab+ CD4+ CD45RA+ CCR7+. Here, we report the results of the pilot phase of the cape cohort (NCT02734290).

Results: Twelve of 14 subjects were treated in the first-line setting. All subjects (14/14, 100%) tolerated cape+pembro for >6 weeks, with toxicities consistent with monotherapy cape experience (diarrhea: grade I-II 50%, grade III 7%; hand-foot: grade I-II 71%) that improved with dose-reduction as needed. At 12 weeks, the ORR was 6/14 (42.9%), and the clinical benefit rate (ORR + stable disease) was 8/14 (57.1%). Depressed absolute lymphocyte count at baseline (ALC<1.0/uL: 33% CBR; ALC≥1.0/uL: 75% CBR) and recent exposure to cytotoxic chemotherapy (<6 months: 33% CBR; >6 months: 75% CBR) were associated with reduced clinical benefit. By flow cytometry, subjects experiencing clinical benefit had higher baseline absolute naïve CD4+ counts (average 283 cells/uL v. 93 cells/uL, p=.069).

Conclusions: This study met the primary endpoint of safety for cape plus pembro in mTNBC, with encouraging clinical activity. These data are supportive of further studies evaluating combination chemotherapy plus anti-PD-1/L1 mTNBC. We observed greater clinical benefit in subjects with non-suppressed ALC, less exposure to recent chemo, and higher baseline naïve CD4+ counts, suggesting that iatrogenic immunosuppression can impair response to immune checkpoint therapy in mTNBC. These findings should be confirmed in ongoing randomized trials of immune checkpoint +/- chemotherapy in mTNBC, and should be considered in the design of future clinical trials.

Citation Format: Page DB, Pucilowska J, Bennetts L, Kim I, Sanchez K, Martel M, Conlin A, Moxon N, Mellinger S, Acheson A, Kemmer K, Mitri Z, Vuky J, Ahn J, Abaya C, Manigault T, Basho R, Urba WJ, McArthur HL. Updated efficacy of first or second-line pembrolizumab (pembro) plus capecitabine (cape) in metastatic triple negative breast cancer (mTNBC) and correlations with baseline lymphocyte and naïve CD4+ T-cell count [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 P2-09-03.

New onset acute pulmonary edema after methylergonovine given during cesarean delivery of a patient with undiagnosed Raynaud's disease

Raynaud's disease is a medical condition in which arterial spasm causes episodes of reduced blood flow, in the setting of certain triggers such as cold weather. Patients with this condition are at risk of adverse reactions if they receive medications with vasoactive properties. Methylergonovine maleate is one drug used during cesarean delivery to treat postpartum hemorrhage due to uterine atony. By acting directly on uterine and vascular smooth muscle, it produces cardiovascular responses such as coronary vasospasm, myocardial infarction, and even cardiac arrest. However, pulmonary events have rarely been reported. We report our anesthetic management of a 36-year-old patient, with undiagnosed Raynaud's disease and undergoing cesarean delivery, who experienced new onset acute pulmonary edema after methylergonovine administration to manage postpartum hemorrhage.

Parkinson's disease and the risk of osteoporotic vertebral compression fracture: a nationwide population-based study

Patients with Parkinson's disease (PD) were at higher risk of osteoporotic vertebral compression fractures (OVCF) compared to controls and had elevated mortality rates. Compared to conservative treatment, surgical treatment for OVCF in PD patients seemed to be associated with better outcomes.

INTRODUCTION

The purpose of this study was to evaluate the risk of OVCF in patients with PD.

METHODS

Data from patients over the age of 60 years who were diagnosed with PD were collected between 2004 and 2013 from the Korean National Health Insurance Database (n = 3370). The comparison group (non-PD) consisted of randomly selected patients (five per patient with PD; n = 16,850) matched to the PD group, who were newly diagnosed annually according to age and sex. Cox proportional hazard regressions were used to examine the relationships between osteoporosis, OVCF, surgery for OVCF, and PD. Household income and residential area of patients were also assessed. Overall survival rates were calculated after adjusting for confounding factors, such as hypertension, diabetes mellitus, and chronic kidney disease.

RESULTS

OVCF was developed in 12.5% of patients in the PD group and in 7.4% of patients in the control group. PD was associated with increased risk of osteoporosis (hazard ratio [HR], 1.32; 95% confidence interval [CI], 1.21-1.43; p < 0.001), OVCF (HR 1.66; 95% CI, 1.47-1.87; p < 0.001), and surgery for OVCF (HR 2.69; 95% CI, 1.78-4.08; p < 0.001). Household income was not significantly related with development of osteoporosis, incidence of OVCF, or surgery for OVCF. Residential area was statistically associated with osteoporosis, OVCF, and surgery for OVCF. The mortality rate of the PD group was about 1.7 times higher than that of the non-PD group after adjusting for potential confounders, and the mortality rate of the PD with OVCF group was higher than that of the non-PD group, but not significantly (p = 0.09). The survival rate of the PD group with surgery for OVCF showed a trend toward a more positive prognosis compared with that of the PD group with conservative treatment.

CONCLUSIONS

Patients with PD had significantly increased risk of osteoporosis and OVCF. Surgical treatment for OVCF in PD patients was associated with a better prognosis than conservative treatment.

Serum LDH and LDH Isoenzymes in Chronic Renal Failure: Effect of Hemodialysis

Serum levels of several commonly measured enzymes are abnormal in patients with end-stage renal disease (ESRD). In the present study we measured serum total LDH activity and LDH isoenzymes in a group of 25 ESRD patients shortly before, during, and immediately after hemodialysis. Baseline serum total LDH activity in the ESRD group was midly but significantly higher than that found in the normal control group. The observed elevation was associated with an isomorphic pattern. Single passage of blood through the extracorporeal apparatus led to a rise in total LDH, LDH-3, LDH-2 and LDH-4, a pattern consistent with release from the platelets. A steady increase was noted in total LDH, LDH-5 and LDH-1 of arterial blood during hemodialysis. This was thought to be due to ultrafiltration-induced hemoconcentration, enzyme release from the formed elements within the extracorporeal circuit and complement-mediated leukocyte activation and pulmonary leukostasis. These observations should be taken into consideration with regards to interpretation of LDH and LDH isoenzyme values and proper time of blood sampling in ESRD patients.