Prostate cancer, comorbidity, and participation in randomized controlled trials of therapy

Hydrolysis of ATP, ADP, and AMP is increased in blood plasma of prostate cancer patients

Prostate cancer is among the major malignancies that affect men around the world. Adenine nucleotides are important signaling molecules that mediate innumerous biological functions in pathophysiological conditions, including cancer. These molecules are degraded by several ectoenzymes named ectonucleotidases that produce adenosine in the extracellular medium. Some of these ecto-enzymes can be found in soluble in the blood stream. Thus, the present study aimed to evaluate the hydrolysis of adenine nucleotides (ATP, ADP, and AMP) in the plasma blood of patients with prostate cancer. Peripheral blood samples were collected, and questionnaires were filled based on the clinical data of the medical records. The nucleotide hydrolysis was performed by Malachite Green method using ATP, ADP, and AMP as substrates. Plasma from prostate cancer patients presented an elevated hydrolysis of all nucleotides evaluated when compared to healthy individuals. NTPDase inhibitor (ARL67156) and the alkaline phosphatase inhibitor (levamisole) did not alter ATP hydrolysis. However, AMP hydrolysis was reduced by the CD73 inhibitor, APCP, and by levamisole, suggesting the action of a soluble form of CD73 and alkaline phosphatase. On microvesicles, it was observed that there was a low expression and activity of CD39 and almost absent of CD73. The correlation of ATP, ADP, and AMP hydrolysis with clinic pathological data demonstrated that patients who received radiotherapy showed a higher AMP hydrolysis than those who did not, and patients with lower clinical stage (CS-IIA) presented an elevated ATP hydrolysis when compared to those with more advanced clinical stages (CS-IIB and CS-III). Patients of all clinical stages presented an elevated AMPase activity. Therefore, we can suggest that the nucleotide hydrolysis might be attributed to soluble ecto-enzymes present in the plasma, which, in a coordinate manner, produce adenosine in the blood stream, favoring prostate cancer progression.

Extent of Exclusions for Chronic Conditions in Breast Cancer Trials

Experts have expressed concerns that patients with chronic conditions are being excessively excluded from cancer randomized clinical trials (RCTs), limiting generalizability. Accordingly, we queried clinicaltrials.gov to determine the extent to which patients with chronic conditions were excluded from phase III cancer trials, using National Cancer Institute-sponsored breast cancer RCTs as a test case. Two physicians independently coded for the presence of 19 prevalent chronic conditions within eligibility criteria. They also coded for exclusions based on performance status and vague criteria that could have broadly excluded patients with chronic conditions. The search identified 58 RCTs, initiated from 1993 to 2012. Overall, 88% of trials had at least one exclusion for a chronic condition, performance status, or vague criterion. The three most commonly excluded conditions were chronic kidney disease, heart failure, and ischemic heart disease. Our study demonstrated that patients with prevalent chronic conditions were commonly excluded from National Cancer Institute-sponsored RCTs.

Impact of comorbidity on the outcome in men with advanced prostate cancer treated with docetaxel

Background

Men with metastatic castrate-resistant prostate cancer (mCRPC) may not receive docetaxel in everyday clinical practice due to comorbidities. Here we explore the impact of comorbidity on outcome in men with mCRPC treated with docetaxel in a population-based outcome study.

Methods

Men with mCRPC treated with docetaxel at the Institute of Oncology Ljubljana between 2005 and 2012 were eligible. Comorbidity was assessed by the age-adjusted Charlson comorbidity index (aa-CCI) and adult comorbidity evaluation (ACE-27) index. Hospital admissions due to the toxicity and deaths during treatment with docetaxel were used as a measure of tolerability. Association between comorbidity and overall survival (OS) was tested using the Cox proportional hazards analysis.

Results

Two hundred and eight men were treated with docetaxel. No, mild, moderate and severe comorbidity was present in 2%, 32%, 53% and 13% using aa-CCI and in 27%, 35%, 29% and 8% when assessed by ACE-27. A substantial dose reduction of docetaxel occurred more often in men with moderate or severe comorbidity as compared to those with no or mild comorbidity. At all comorbidity levels about one-third of men required hospitalization or died during treatment with docetaxel. In univariate analysis a higher level of comorbidity was not associated with worse OS (aa-CCI HR 0.99; [95% CI 0.87–1.13], p = 0.93; ACE-27: HR 0.96; [95% CI 0.79–1.17], p = 0.69).

Conclusions

Men with mCRPC, who have comorbidities may benefit from treatment with docetaxel.

Influence of age on incident diabetes and cardiovascular disease in prostate cancer survivors receiving androgen deprivation therapy

PURPOSE

Observational data suggest that androgen deprivation therapy increases the risk of diabetes and cardiovascular disease. Using data from the population based PCOS we evaluated whether age at diagnosis and comorbidity impact the association of androgen deprivation therapy with incident diabetes and cardiovascular disease.

MATERIALS AND METHODS

We identified men with nonmetastatic prostate cancer diagnosed from 1994 to 1995 who were followed through 2009 to 2010. We used multivariable logistic regression models to assess the relationship of androgen deprivation therapy exposure (2 or fewer years, greater than 2 years or none) with incident diabetes and cardiovascular disease, adjusting for age at diagnosis, race, stage and comorbidity.

RESULTS

Of 3,526 eligible study participants 2,985 without diabetes and 3,112 without cardiovascular disease comprised the cohorts at risk. Androgen deprivation therapy was not associated with an increased risk of diabetes or cardiovascular disease in men diagnosed with prostate cancer before age 70 years. Prolonged androgen deprivation therapy and increasing age at diagnosis in older men was associated with an increased risk of diabetes (at age 76 years OR 2.1, 95% CI 1.0-4.4) and cardiovascular disease (at age 74 years OR 1.9, 95% CI 1.0-3.5). Men with comorbidities were at greater risk for diabetes (OR 4.3, 95% CI 2.3-7.9) and cardiovascular disease (OR 8.1, 95% CI 4.3-15.5) than men without comorbidities.

CONCLUSIONS

Prolonged androgen deprivation therapy exposure increases the risk of cardiovascular disease and diabetes in men diagnosed with prostate cancer who are older than approximately 75 years, especially those with other comorbidities. Older men who receive prolonged androgen deprivation therapy should be closely monitored for diabetes and cardiovascular disease.

Comorbidities and Concomitant Medication Use in Men with Prostate Cancer or High Levels of PSA Compared to Matched Controls: A GPRD Analysis

Comorbidity influences screening practice, treatment choice, quality of life, and survival. The presence of comorbidities and medication use could place patients at greater risks of adverse effects from certain interventions. We conducted a longitudinal cohort study in the General Practice Research Database to better understand comorbidities and medication use in men with or at risk of prostate cancer (CaP). Compared with men with similar age but no CaP, CaP patients had higher incidence of urinary tract infection, impotence and breast disorder, and 2.6-fold higher all-cause mortality. Among men with elevated prostate-specific antigen (PSA) but no CaP, the mortality rates were slightly lower, and fewer differences in comorbidities and medication use were noted compared to men without elevated PSA. Many prevalent comorbidities and medications were consistent across groups and are typical of an older male population. These real-world data are broadly applicable throughout the drug development cycle and subsequent patient management.