Adherence in Cancer Screening Trial
False-positive results in a cancer screening trial can significantly affect health-related quality of life (HRQL) and adherence to the trial. A study in the July 21 Journal of the National Cancer Institute examines these two issues in the context of a cancer screening
trial, compared with the more frequently studied trials for cancer treatment, prevention, or symptom management. Dr. Kathryn Taylor and colleagues at Georgetown University School of Medicine assessed HRQL and trial adherence of 432 participants of NCI's Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, designed to assess whether annual screenings will reduce mortality rates. Individuals in both the control and screening groups were interviewed before
the initial screening and requested to complete questionnaires 1 year later. Individuals in the screening group were also interviewed shortly after receiving test results, about 3 months after the baseline assessment.
Researchers found that individuals who received an abnormal, potentially cancerous result experienced a short-term decrease in HRQL. At the 1-year interval, when the abnormal result had been shown to be a false-positive,
these individuals had returned to baseline HRQL levels, indicating that false-positive results did not have lasting
effects on HRQL. False-positive results did have long-term implications
in terms of adherence, however. Of the participants who responded, only 78.7 percent of those who had received abnormal results completed all the required follow-up screenings at the 1-year interval, compared with a 93.7 percent completion rate among individuals receiving normal results. "Focusing additional attention and trial resources on nonadherent subgroups,
including those who received false-positive results, may improve overall adherence rates in a cost-efficient manner," Dr. Taylor said.
Clinical Trials and
Mandated Reimbursement
Cancer patients living in states where legislation mandated third-party reimbursement
for medical costs for clinical trial participants were more likely to enroll in phase II clinical trials than patients in states where reimbursement was not mandated, according to a study in the July 21 Journal of the National Cancer Institute, funded in part by NCI. Dr. Cary P. Gross and colleagues at Yale University studied whether effects of state-issued reimbursement plans were associated with an increase in NCI Clinical Trials Cooperative Group enrollment from 1996-2001.
Researchers analyzed 72,709 patient records in phase II and III clinical trials to assess trends associated with reimbursement legislation and trial enrollment. States with mandated repayment
policies showed a statistically significant increase in trial enrollment during the study period over those states without such legislation. Investigators
also analyzed a study sample of privately insured patients and found a statistically significant increase in both phase II and III trial enrollment in states with and without mandatory
reimbursement policies; the rate of increase in states with mandated reimbursement was found to be significantly
higher compared with states without mandated reimbursement.
Though enrollment in phase II trials was increased in states with mandatory
reimbursement policies, overall trial enrollment and enrollment in phase III studies did not increase substantially. Researchers suggest that "…physician and patient knowledge, beliefs, and attitudes concerning trials,
as well as logistical barriers, have a greater influence on patient participation
than legislative mandates."
High-Dose Chemo for
Advanced Breast Cancer
High-dose chemotherapy does not improve survival rates for women with metastatic breast cancer and multiple positive lymph nodes, compared with conventional adjuvant chemotherapy. A randomized trial of 605 patients with high-risk breast cancer compared treatment
with high-dose chemotherapy using
stem cell transplant versus conventional
chemotherapy, and showed that there were no significant differences in survival rates at the 6-year follow-up.
Dr. Robert Leonard and colleagues from the Anglo-Celtic Cooperative Oncology Group noted in the July 21 Journal of the National Cancer Institute that previous uncontrolled studies suggested better results with high-dose chemotherapy.
The two groups of women - all with four or more positive lymph nodes - were randomly assigned to receive either conventional therapy or high-dose therapy with stem cell transplant. Most women in both groups were prescribed 5 years of tamoxifen treatment.
Breast cancer patients with four or more positive lymph nodes have a poor prognosis - approximately two-thirds will develop fatal metastases. Adjuvant therapy using the anthracycline-containing
combination chemotherapies
is the currently accepted standard.
"There was no statistically significant difference in relapse-free survival between
the arms of the trial," the authors noted. "These results indicate that the single, high-dose…chemotherapy strategy confers extra cost and toxicity
without added anticancer benefit." The study was conducted with support from Amgen Limited (UK).
Screening Saved 5,500 Lives, Study Says
A national cervical cancer screening
program in the United Kingdom (UK) has prevented an estimated 5,500 deaths annually among women born after 1950, according to a study in the July 17 Lancet. The study, funded by Cancer Research UK, was conducted to determine whether the screening program, launched in 1988, was an economically and socially sound investment of resources.
Using age-cohort modeling, the
researchers, led by Dr. Julian Peto of the London School of Hygiene and
Tropical Medicine, looked at all uterine
cancer mortality rates obtained from
the World Health Organization
database from 1985-1999 for 38 countries in Europe, North America, and Australia, and cervical cancer death rates among women in the UK. Overall, the UK had the highest mortality rate for women aged 30-34, compared with Western Europe,
North America, and Australia. However,
10 years after the UK national screening program was initiated, the mortality rate in this birth cohort had the smallest increase of any developed
country. Without any screening, the researchers concluded, an estimated 11,000 women in the UK would have had invasive cancers, resulting in 5,500 deaths per year by 2030. The screening program has saved 1 in 65 women from dying of cervical cancer in the UK, they wrote, at a cost per life saved of $67,000 (US).
|