Association between concomitant use of hydrochlorothiazide and adverse chemotherapy-related events among older women with breast cancer treated with cyclophosphamide

Background: The pharmacy reference database, Micromedex, lists concomitant hydrochlorothiazide and cyclophosphamide use as a potential, major drug-drug interaction (DDI), although only one small, single-center study supports this claim. Our objective was to estimate associations between this potential DDI and two adverse chemotherapy-related events, neutropenia-related hospitalizations and treatment regimen discontinuation, among a cohort of women with breast cancer initiating adjuvant chemotherapy containing cyclophosphamide. Methods: Using linked Surveillance, Epidemiology, and End Results Program (SEER)-Medicare data, we included women 66 years and older with breast cancer diagnosis between 2007 and 2011, who initiated a regimen containing cyclophosphamide. Risk ratios (RR) and 95% confidence intervals for adverse outcomes comparing women exposed versus unexposed to the potential DDI were assessed using modified multivariable Poisson regression adjusting for potential confounders. Results: In total, 27% of women receiving cyclophosphamide treatment were exposed to concomitant hydrochlorothiazide, of which 11% experienced a neutropenia-related hospitalization and 21% discontinued their chemotherapy regimen prior to completion. Adjusted risks of both adverse events were similar between those exposed and unexposed to the potential DDI [neutropenia-related hospitalization: adjusted RR (aRR) = 0.92 (0.70-1.21); treatment discontinuation: aRR = 1.00 (0.96-1.05)]. Conclusions: Our results do not support an association between concomitant hydrochlorothiazide use and two clinically relevant adverse chemotherapy-related events. Impact: Our results support reassessing and potentially lowering severity of this potential interaction in drug reference databases

Potential medication-related problems in older breast, colon, and lung cancer patients in the United States

Background: Older adults are often exposed to multiple medications, some of which could be inappropriate or have the potential to interact with each other. Older cancer patients may be at increased risk for medication-related problems due to exposure to cancer-directed treatment. Methods: We described patterns of potentially inappropriate medication (PIM) use and potential drug-chemotherapy interactions among adults age 66+ years diagnosed with stage I-III breast, stage II-III colon, and stage I to II lung cancer. Within the Surveillance, Epidemiology, and End Results-Medicare database, patients had to have Medicare Part D coverage with 1+ prescription in the diagnosis month and Medicare Parts A/B coverage in the prior 12 months. We estimated monthly prevalence of any and cancer-related PIM from 6 months pre- to 23 months post-cancer diagnosis and 12-month period prevalence of potential drug- chemotherapy interactions. Results: Overall, 19,318 breast, 7,283 colon, and 7,237 lung cancer patients were evaluated. Monthly PIM prevalence was stable prediagnosis (37%-40%), but increased in the year following a colon or lung cancer diagnosis, and decreased following a breast cancer diagnosis. Changes in PIM prevalence were driven primarily by cancer-related PIM in patients on chemotherapy. Potential drug-chemotherapy interactions were observed in all cohorts, with prevalent interactions involving hydrochlorothiazide, warfarin, and proton-pump inhibitors. Conclusions: There was a high burden of potential medication-related problems among older cancer patients; future research to evaluate outcomes of these exposures is warranted. Impact: Older adults diagnosed with cancer have unique medication management needs. Thus, pharmacy specialists should be integrated into multidisciplinary teams caring for these patients

Patterns of Sociodemographic and Clinicopathologic Characteristics of Stages II and III Colorectal Cancer Patients by Age: Examining Potential Mechanisms of Young-Onset Disease

Background and Aims. As a first step toward understanding the increasing incidence of colorectal cancer (CRC) in younger (age < 50) populations, we examined demographic, clinicopathologic, and socioeconomic characteristics and treatment receipt in a population-based sample of patients newly diagnosed with stages II and III CRC. Methods. Patients were sampled from the National Cancer Institute's Patterns of Care studies in 1990/91, 1995, 2000, 2005, and 2010 (n=6,862). Tumor characteristics and treatment data were obtained through medical record review and physician verification. We compared sociodemographic and clinicopathologic characteristics and treatment patterns of younger (age < 50) and older (age 50-69, age ≥ 70) CRC patients. Results. Younger patients were more likely to be black (13%) and Hispanic (15%) than patients aged 50-69 years (11% and 10%, resp.) and ≥70 years (7% each). A larger proportion of young white (41%) and Hispanic (33%) patients had rectal tumors, whereas tumors in the right colon were the most common in young black patients (39%). The majority of younger patients received chemotherapy and radiation therapy, although receipt of microsatellite instability testing was suboptimal (27%). Conclusion. Characteristics of patients diagnosed with young-onset CRC differ considerably by race/ethnicity, with a higher proportion of black and Hispanic patients diagnosed at the age of < 50 years

Inflammatory markers and overall survival in older adults with cancer

Background: Our aim was to evaluate the prognostic impact of three inflammatory markers - neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR) and lymphocyte monocyte ratio (LMR) - on overall survival (OS) in older adults with cancer. Materials and Methods: Our sample includes 144 patients age ≥ 65 years with solid tumor cancer who completed a cancer-specific Geriatric Assessment (GA) from 2010 to 2014 and had pretreatment CBC with differential. NLR was dichotomized a previously reported cut-off value of 3.5, while PLR and LMR were dichotomized at the median. Cox proportional hazards models evaluated whether NLR, PLR and LMR were predictive of OS independent of covariates including a recently developed 3-item GA-derived prognostic scale consisting of (1) “limitation in walking several blocks” (2) “limitation in shopping” and (3) “≥ 5% unintentional weight loss in 6 months”. Results: Median age was 72 years, 53% had breast cancer, 27% had stage 4 cancer, 14% had Karnofsky Performance Status (KPS) 3.5. In univariable analysis, higher NLR and PLR and lower LMR were significantly associated with worse OS. NLR remained a significant predictor of OS (HR = 2.16, 95% CI; 1.10–4.25, p =.025) after adjusting for cancer type, stage, age, KPS, treatment intensity, and the GA-derived prognostic scale. Conclusion: NLR > 3.5 is predictive of poorer OS in older adults with cancer, independent of traditional prognostic factors and the GA-derived prognostic scale

Oncology pharmacist-led medication reconciliation among cancer patients initiating chemotherapy

Background: Pharmacist-led medication reconciliation (PMR) ensures adequate recording and use of medications by patients. PMR may be important for cancer patients initiating new therapies, as they have a high burden of medication use and are more susceptible to inadvertent medication discrepancies. To describe medication changes (additions, discontinuations, and modifications) made to the electronic health record during a PMR among cancer patients initiating chemotherapy. Methods: From October 2011 to March 2012, 397 cancer patients initiating chemotherapy underwent a PMR at the University of North Carolina Cancer Hospital. Self-reported medications and those in the patients’ electronic health record were reviewed. Log-binomial regression models were used to estimate adjusted prevalence ratios and 95% confidence intervals for the associations between patient characteristics and medication changes made to the electronic health record. Results: Mean age at time of the PMR was 58. Median number of medications taken prior to the PMR was 10 and median time to PMR completion was 11 min. Vitamins and herbal supplements accounted for the largest proportion of medication additions (38%) and modifications (20%). Antimicrobials accounted for the largest share of discontinuations (15%). After adjustment for all other covariates, patients aged 60–69 years were more likely to have additions than those aged 50 and under (aPR = 1.47, 95%CI: 1.10–1.97). Patients 70 years and over were more likely to have modifications (aPR = 1.74, 95%CI: 1.07–2.82). Conclusion: Our results show that most cancer patients had a medication change in the electronic health record. A brief oncology PMR can accurately capture and improve medication safety by preventing prescribing and administration errors

The incremental value of a geriatric assessment-derived three-item scale on estimating overall survival in older adults with cancer

Objective: A geriatric assessment (GA) assesses functional age of older patients with cancer and is a well-established tool predictive of toxicity and survival. The objective of this study was to investigate the prognostic value of individual GA items. Materials and Methods: 546 patients with cancer ≥ 65 years completed GA from 2009 to 2014 and were followed for survival status for a median of 3.7 years. The GA consisted of function, nutrition, comorbidity, cognition, psychological state, and social activity/support domains. GA items with p < 0.05 in univariable analyses for overall survival (OS) were entered into multivariable stepwise selection procedure using a Cox proportional hazards model. A prognostic scale was constructed with significant GA items retained in the final model. Results: Median age was 72 years, 49% had breast cancer, and 42% had stage 3–4 cancer. Three GA items were significant prognostic factors, independent of traditional factors (cancer type, stage, age, and Karnofsky Performance Status): (1) “limitation in walking several blocks”, (2) “limitation in shopping”, and (3) “≥ 5% unintentional weight loss in 6 months”. A three-item prognostic scale was constructed with these items. In comparison with score 0 (no positive items), hazard ratios for OS were 1.85 for score 1, 2.97 for score 2, and 8.67 for score 3. This translated to 2-year estimated survivals of 85%, 67%, 51% and 17% for scores of 0, 1, 2 and 3, respectively. Conclusions: This three-item scale was a strong independent predictor of survival. If externally validated, this could be a streamlined tool with broader applicability

Antibacterial Use Is Associated with an Increased Risk of Hematologic and Gastrointestinal Adverse Events in Patients Treated with Gemcitabine for Stage IV Pancreatic Cancer

Background: Preclinical evidence has demonstrated that common intratumor bacteria metabolize the chemotherapeutic drug gemcitabine. The significance of this bacterial metabolism pathway, relative to the known metabolic pathways by host enzymes, is not known. We hypothesized that bacterial metabolism is clinically significant and that “knockdown” by antibacterial therapy has the unintended effect of increasing the effective dose of gemcitabine, thereby increasing the risk for gemcitabine-associated toxicities. Materials and Methods: We reanalyzed the comparator arm of the MPACT trial (NCT01442974), made available through Project Data Sphere, LLC (CEO Roundtable on Cancer's Life Sciences Consortium, Cary, NC; www.projectdatasphere.org). In this arm, 430 patients with metastatic pancreatic adenocarcinoma were treated with gemcitabine. We used the Anderson-Gill survival model to compare the risk of developing an adverse event after antibacterial prescription with time unexposed to antibacterials. Adverse events of grade 3 and greater were considered at three levels of granularity: all aggregated into one endpoint, aggregated by class, and taken individually. Antibiotic exposures were analyzed in aggregate as well as by class. Results: Antibacterial exposure was associated with an increased risk of adverse events (hazard ratio [HR]: 1.77; confidence interval [CI]: 1.46–2.14), any hematologic adverse event (HR: 1.64; CI: 1.26–2.13), and any gastrointestinal adverse event (HR: 2.14; CI: 1.12–4.10) but not a constitutional (HR: 1.33; CI: 0.611–2.90) or hepatologic adverse event (HR: 0.99; CI: 0.363–2.71). Among specific adverse events, antibacterial exposure was associated with an increased risk of anemia (HR: 3.16; CI: 1.59–6.27), thrombocytopenia (HR: 2.52; CI: 1.31–4.85), leukopenia (HR: 3.91; CI: 1.46–10.5), and neutropenia (HR: 1.53; CI: 1.07–2.17) but not any other specific adverse events. Conclusion: Antibacterial exposure was associated with an increased risk of gemcitabine-associated, dose-limiting adverse events, including aggregate hematologic and gastrointestinal events, as well as four specific hematologic adverse events, suggesting that intratumor bacteria may be responsible for a clinically significant portion of gemcitabine metabolism. Alternative avenues of evidence will be necessary to confirm this preliminary finding and assess its generalizability. There is plentiful opportunity for similar analyses on other clinical trial data sets, where gemcitabine or other biomimetic small molecules were used. Implications for Practice: Patients treated with gemcitabine for metastatic pancreatic ductal adenocarcinoma have an increased rate of gemcitabine-associated toxicity during and after antibiotic therapy. This observation is consistent with preclinical evidence that intratumor bacteria metabolize gemcitabine to an inactive form. Further research is needed to determine whether this observation merits any changes in clinical practice

Molecular and clinical characterization of a claudin-low subtype of gastric cancer

Purpose Claudin-low molecular subtypes have been identified in breast and bladder cancers and are characterized by low expression of claudins, enrichment for epithelial-to-mesenchymal transition (EMT), and tumor-initiating cell (TIC) features. We evaluated whether the claudin-low subtype also exists in gastric cancer. Materials and Methods Four hundred fifteen tumors from The Cancer Genome Atlas (TCGA) gastric cancer mRNA data set were clustered on the claudin, EMT, and TIC gene sets to identify claudin-low tumors. We derived a 24-gene predictor that classifies gastric cancer into claudin-low and non-claudin-low subtypes. This predictor was validated with the Asian Cancer Research Group(ACRG)data set. We characterized molecular and clinical features of claudin-low tumors. Results We identified 46 tumors that had consensus enrichment for claudin-low features in TCGA data set. Claudin-low tumors were most commonly diffuse histologic type (82%) and originally classified as TCGA genomically stable(GS)subtype (78%). Compared with GS subtype, claudin-low subtype had significant activation in Rho family of GTPases signaling, which appears to play a key role in its EMT and TIC properties. In the ACRG data set, 28 of 300 samples were classified as claudin-low tumors by the 24-gene predictor and were phenotypically similar to the initially derived claudin-low tumors. Clinically, claudin-low subtype had the worst overall survival. Of note, the hazard ratios that compared claudin-low versus GS subtype were 2.10 (95% CI, 1.07 to 4.11) in TCGA and 2.32 (95% CI, 1.18 to 4.55) in the ACRG cohorts, with adjustment for age and pathologic stage. Conclusion We identified a gastric claudin-low subtype that carries a poor prognosis likely related to therapeutic resistance as a result of its EMT and TIC phenotypes

Effectiveness of adjuvant FOLFOX vs 5FU/LV in adults over age 65 with stage II and III colon cancer using a novel hybrid approach

Purpose: Estimates of cancer therapy effects can differ in clinical trials and clinical practice, partly due to underrepresentation of certain patient subgroups in trials. We utilize a hybrid approach, combining clinical trial and real-world data, to estimate the comparative effectiveness of two adjuvant chemotherapy regimens for colon cancer. Methods: We identified patients aged 66 and older enrolled in the Multicenter International Study of Oxaliplatin/5FU-LV in the Adjuvant Treatment of Colon Cancer. Similar patients were identified in the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, initiating adjuvant chemotherapy with either 5-fluorouracil (5FU) alone or in combination with oxaliplatin (FOLFOX). We used logistic regression to estimate the likelihood of trial enrollment as a function of age, sex, and substage. Using inverse odds of sampling weights (IOSW), we compared 5-year mortality in patients randomized to FOLFOX vs 5FU using weighted Cox proportional hazards regression, the Nelson-Aalen estimator for cumulative hazards, and bootstrapping for 95% confidence intervals (CIs). Results: There were 690 trial participants and 3834 SEER-Medicare patients. The SEER-Medicare population was older and had a higher proportion of stage IIIB and IIIC patients than the trial. After controlling for differences between populations, the IOSW 5-year HR was 1.21 (0.89, 1.65), slightly farther from the null than the trial estimate (HR = 1.14, 95%CI: 0.87, 1.49). Conclusions: This study supports mounting evidence of little to no incremental reduction in 5-year mortality for FOLFOX vs 5FU in older adults with stage II-III colon cancer, emphasizing the importance of combining clinical trial and real-world data to support such conclusions