Potentially Inappropriate Medication Use in Older Patient with Breast and Colorectal Cancer

Our objective was to determine predictors of potentially inappropriate medication (PIM) use and its impact on outcomes (including ER visits, hospitalization, all cause death, and composite of three) in breast and colorectal cancer patients receiving chemotherapy. We used data from the SEER database linked to Medicare claims. Our cohort included patients ≥ 66 years diagnosed with of Stage II/III breast or colorectal cancer between 7/1/2007-12/31/2009. Baseline PIM was defined using the Drugs to Avoid in the Elderly list (DAE) or Beers criteria. Univariate and multivariable logistic regression were used to determine the associations of baseline PIMs with different covariates. Event-free survival (EFS) was defined from the initiation of chemotherapy to outcome, and estimated using the KM method. Cox proportional hazards modeling was used to determine the association of baseline PIMs with EFS. The final analysis included 1595 breast and 1528 colorectal patients. The frequency of baseline PIM was 22.2% (DAE) and 27.6% (Beers) in the breast cohort, and 15.5% (DAE) and 24.8% (Beers) in the colorectal cohort. Baseline PIM was associated with younger age, baseline ≥5 medications, and female gender. In the breast cohort, 37.5% patients had at least one composite outcome. One-year EFS rate was 49%, 62%, 96%, and 45% for ER, hospitalization, death, and composite respectively. Variables associated with increased risk of the composite outcome included baseline ≥5 medications, advanced stage, higher comorbidity, and baseline ER/hospitalization. Baseline PIM using DAE was associated with increased risk of death in the breast cohort, HR 2.31 (95% CI 1.07-4.96). 45% of patients in the colorectal cohort had at least one composite outcome. One-year EFS rate was 42%, 54%, 91%, and 38% respectively. Variables associated with an increased risk of the composite outcome in colorectal patients included baseline ≥ 5 medications, older age, female gender, higher comorbidity. In the time-to-event analysis, we found no association between baseline PIM and most outcomes in either group, aside from baseline PIM using DAE and death in the breast cohort during chemotherapy. Baseline ≥5 medications was associated with increased risks of adverse outcomes in both. Our findings require further prospective confirmation but call into doubt the need to reduce PIM in older patients during chemotherapy

Rapid Breast Cancer Disease Progression Following Cyclin Dependent Kinase 4 and 6 Inhibitor Discontinuation.

Background: CDK 4 and 6 inhibitors (CDK4/6i), which arrest unregulated cancer cell proliferation, show clinical efficacy in breast cancer. Unexpectedly, a patient treated on a CDK4/6i-based trial, as first-line therapy in metastatic breast cancer, developed rapid disease progression following discontinuation of study drug while receiving standard second-line therapy off trial. We thus sought to expand this observation within a population of patients treated similarly at The University of Texas MD Anderson Cancer Center. Methods: Using an IRB-approved protocol, 4 patients previously enrolled on CDK4/6i trials were analyzed for outcomes after discontinuing study drug. These patients were treated on a randomized trial of first-line endocrine therapy +/- a CDK4/6i. Rapid disease progression was defined as progression occurring within 4 months of CDK4/6i discontinuation. Results: In total, 4 patients developed rapid disease progression and died; 2 of whom died within 6 months of CDK4/6i discontinuation. Conclusion: This case series suggests a potential for rapid disease progression following CDK4/6i discontinuation. However, the clinical course following progression must be validated in large CDK4/6i clinical trials and standard-of-care cohorts. If confirmed, such observations may alter the algorithm for subsequent therapy in patients with disease progression on CDK4/6i. Nevertheless, the need remains to define a mechanistic basis for this rapid progression and formulate alternative therapeutic strategies

Understanding cognition in older patients with cancer

Cancer and neurocognitive disorders, such as dementia and delirium, are common and serious diseases in the elderly that are accompanied by high degree of morbidity and mortality. Furthermore, evidence supports the under-diagnosis of both dementia and delirium in older adults. Complex questions exist regarding the interaction of dementia and delirium with cancer, beginning with guidelines on how best measure disease severity, the optimal screening test for either disorder, the appropriate level of intervention in the setting of abnormal findings, and strategies aimed at preventing the development or progression of either process. Ethical concerns emerge in the research setting, pertaining to the detection of cognitive dysfunction in participants, validity of consent, disclosure of abnormal results if screening is pursued, and recommended level of intervention by investigators. Furthermore, understanding the ways in which comorbid cognitive dysfunction and cancer impact both cancer and non-cancer-related outcomes is essential in guiding treatment decisions. In the following article, we will discuss what is presently known of the interactions of pre-existing cognitive impairment and delirium with cancer. We will also discuss identified deficits in our knowledge base, and propose ways in which innovative research may address these gaps

Delayed initiation of adjuvant chemotherapy in older women with breast cancer

Abstract Background Adjuvant chemotherapy benefits early‐stage breast cancer (BC) patients. Older women receive guideline‐adherent treatment less frequently and experience treatment delays more frequently. We evaluated factors associated with delaying adjuvant chemotherapy and the delays’ survival impact in a large population–based cohort of elderly BC patients. Methods Patients age >66 years diagnosed 2001‐2015 with localized or regional BC were identified in the SEER‐Medicare and Texas Cancer Registry‐Medicare databases. Time from surgery to chemotherapy (TTC) was categorized into four groups: 0‐30, 31‐60, 61‐90, and >90 days. We identified predictors of delays, estimated overall (OS) and BC‐specific (BCSS) survival, and determined the association between TTC and outcome adjusting for other variables. Results Among 28,968 women (median age 71 years), median TTC was 43 days. 10.7% of patients experienced TTC >90 days. Older age, Black or Hispanic race/ethnicity, unmarried status, more comorbidities, hormone receptor‐positivity, mastectomy, Oncotype DX testing, and full state buy‐in were associated with increased risk of delay. Five‐year OS estimates by TTC group were 0.82, 0.81, 0.80, and 0.74, respectively (p<.001). BCSS demonstrated a similar trend (p<.001). Chemotherapy delay was associated with worse OS (HR=1.33, 95%CI 1.25‐1.40) and BCSS (HR=1.39, 95%CI 1.27‐1.53). In subgroup analysis, delayed chemotherapy was associated with worse OS and BCSS among patients with hormone receptor–positive (HR=1.56, 95%CI 0.97‐2.51), HER2‐positive (HR=1.99, 95%CI 1.04‐3.79), and triple‐negative (HR=2.15, 95%CI 1.38‐3.36) tumors. Conclusion Chemotherapy delays are associated with worse survival in older BC patients. Providers should avoid delays and initiate chemotherapy ≤90 days after surgery regardless of patients’ BC subtype or age

Real-World Analysis of Clinical and Demographic Characteristics, Treatment Patterns, and Outcomes in Predominantly Older Patients with HR+/HER2− Metastatic Breast Cancer Receiving Abemaciclib in Routine Clinical Practice

Abstract Introduction Hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2−) is the most frequently diagnosed metastatic breast cancer (mBC) subtype. Combinations of endocrine therapy (ET) with cyclin-dependent kinase 4/6 inhibitors (CDK4 & 6is) improve outcomes compared with ET alone. The efficacy and safety of abemaciclib among patients with HR+/HER2− mBC has been demonstrated in the MONARCH clinical trials; however, there is a paucity of real-world evidence, particularly in older patients. Methods and Materials This retrospective cohort study analyzed the electronic medical record data/charts of adult patients with HR+/HER2− mBC receiving abemaciclib in US-based community oncology settings (1 September 2017 to 30 September 2019). Patients with other primary malignancies, clinical trial enrollment, and incomplete charts were excluded. Patient characteristics, treatment attributes and patterns, and real-world outcomes (clinical benefit rate [CBR] and stable disease among patients with response data available, time to chemotherapy [TTC], time to treatment discontinuation [TTD], and progression-free survival [PFS]) were summarized. Multivariable models evaluated the association between demographic/clinical characteristics and outcomes. Results Of the 448 final patients, 99% were female, with a median age of 67 years (25% were ≥ 75 years) and median follow-up of 11 months; most (60%) initiated abemaciclib within 2 years of mBC diagnosis. Patients received a median of 1 (P25 = 0, P75 = 3) prior line of therapy for mBC before abemaciclib, including other CDK4 & 6is (48%) and prior chemotherapy (31%); most (57%) had visceral disease. The CBR for the overall population was 53%, with 48% achieving stable disease. The median TTC was not reached; median TTD was 249 days (95% confidence interval [CI]: 202, 304). The median PFS was 329 days (95% CI 266, 386). The discontinuation rate of abemaciclib owing to adverse events (30%) trended higher with age (years) (P = 0.027): 18–49 (n = 42; 19%), 50–64 (n = 155; 25%), 65–74 (n = 138; 32%), 75–84 (n = 82; 37%), ≥ 85 (n = 31; 49%); only 23% of patients overall had a dose hold or reduction prior to discontinuation. Conclusions These patients were older than those in the MONARCH studies with substantial visceral disease, and prior chemotherapy and CDK4 & 6i use. Discontinuation rates were higher than in previous real-world studies (11.9%), highlighting the need for proactive management to optimize outcomes, particularly in older patients with mBC

Efficacy and safety of palbociclib in patients with estrogen receptor–positive/human epidermal growth factor receptor 2–negative advanced breast cancer with preexisting conditions: A post hoc analysis of PALOMA-2

In the PALOMA-2 trial, palbociclib in combination with letrozole prolonged progression-free survival (PFS) and exhibited an acceptable safety profile in patients with estrogen receptor–positive/human epidermal growth factor receptor 2–negative advanced breast cancer (ABC). This post hoc analysis of PALOMA-2 evaluated the efficacy and safety of palbociclib plus letrozole in patients with preexisting conditions grouped by Medical Dictionary for Regulatory Activities (MedDRA) System Organ Class (SOC). Postmenopausal patients without prior treatment for ABC were randomized 2:1 to receive palbociclib (125 mg/d on a 3 weeks on/1 week off schedule) plus letrozole (2.5 mg/d, continuous) or placebo plus letrozole. Patients were grouped by the following MedDRA SOC preexisting conditions: gastrointestinal, musculoskeletal, metabolic, and vascular/cardiac. Median PFS was estimated by the Kaplan-Meier method, and treatment emergent adverse events (AEs) were compared between treatment arms within each preexisting condition subgroup. At baseline, 276 (41.4 %) patients had preexisting gastrointestinal disorders, 390 (58.6 %) had musculoskeletal disorders, 259 (38.9 %) had metabolic disorders, and 382 (57.4 %) had vascular/cardiac disorders. Baseline characteristics were similar between subgroups and between each arm within subgroups. Regardless of baseline preexisting condition, palbociclib plus letrozole prolonged PFS compared with placebo plus letrozole. Treatment-emergent AEs associated with palbociclib plus letrozole and dose modifications due to AEs were similar across preexisting condition subgroups. This post hoc analysis of PALOMA-2 demonstrated a favorable effect of palbociclib on PFS and a safety profile consistent with previous observations, regardless of underlying preexisting condition. Pfizer Inc (NCT01740427). •Preexisting conditions can affect the safety and efficacy of breast cancer therapies.•This is a post hoc analysis of patients with preexisting conditions from PALOMA-2.•Palbociclib prolonged median PFS, regardless of preexisting condition.•Within each treatment arm, AEs were similar regardless of preexisting condition

Abstract PS10-14: Efficacy and safety of palbociclib (PAL) in patients (pts) with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) with preexisting conditions: A post hoc analysis of PALOMA-2

Abstract Background: In the PALOMA-2 trial, PAL + letrozole (LET) significantly prolonged progression-free survival (PFS) vs placebo (PBO) + LET in pts with ER+/HER2– ABC. This post hoc analysis assessed efficacy and safety of PAL + LET in pts from PALOMA-2 with baseline preexisting conditions grouped by Medical Dictionary for Regulatory Activities (MedDRA) System Organ Class (SOC). Methods: Postmenopausal pts with ER+/HER2– ABC received PAL (125 mg/d, 3/1 schedule) + LET (2.5 mg/d, continuous) or PBO + LET. Pts were grouped by the following MedDRA SOC preexisting conditions: Gastrointestinal, Musculoskeletal, Metabolism, and Vascular/Cardiac. Baseline characteristics, PFS, and safety were assessed. Results: At baseline, 41.4% of pts had preexisting gastrointestinal disorders, 58.6% musculoskeletal disorders, 38.9% metabolism disorders, and 57.4% vascular/cardiac disorders. Baseline characteristics were similar between treatment arms within each subgroup and also between subgroups. Within each subgroup, ≥40% of pts also had ≥1 of the other coexisting conditions. Median PFS (mPFS) was significantly longer with PAL + LET vs PBO + LET regardless of preexisting condition (Table). In general, adverse events (AEs) were more frequent with PAL + LET in all subgroups; neutropenia was most common. Within each treatment arm, AEs and dose modifications due to AEs were similar regardless of preexisting condition. Conclusion: PAL + LET showed prolonged PFS and a consistent safety profile regardless of baseline preexisting condition in pts with ER+/HER2– ABC. Clinical trial identification: Pfizer Inc (NCT01740427) TablePreexisting ConditionPAL + LETPBO + LETPAL + LET vs PBO + LETnmPFS (95% CI)nmPFS (95% CI)HR (95% CI)P ValueGastrointestinal17627.6 (17.5–33.1)10013.6 (11.0–18.5)0.57 (0.42–0.78)<0.001Musculoskeletal25227.6 (21.4–33.1)13816.3 (11.2–19.1)0.53 (0.41–0.69)<0.001Metabolism18627.6 (19.3–30.6)7313.8 (8.3–27.4)0.62 (0.44–0.87)0.003Vascular/Cardiac25430.4 (25.1–36.2)12814.5 (11.0–18.5)0.51 (0.39–0.66)<0.001 Citation Format: Karen Gelmon, Janice M Walshe, Reshma Mahtani, Anil A Joy, Meghan Karuturi, Patrick Neven, Dongrui Ray Lu, Sindy Kim, Patrick Schnell, Eustratios Bananis, Lee Schwartzberg. Efficacy and safety of palbociclib (PAL) in patients (pts) with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) with preexisting conditions: A post hoc analysis of PALOMA-2 [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 PS10-14