A recent report in the Centers for Disease Control and Prevention's January 26 Morbidity and Mortality Weekly Report found that mammography rates among women 40 and older significantly declined from 2000 to 2005.
The report summarized the findings from the Behavioral Risk Factor Surveillance System, a state-based, randomly dialed telephone survey of the adult population. The survey, conducted from 2000 to 2005, asked adult female respondents whether they had ever had a mammogram. The women who responded yes to the question were then asked the length of time since their last mammogram.
Mammography rates in women aged 40 and over have declined from 76.4 percent in 2000 to 74.6 percent in 2005, a statistically significant decrease. However, the editors noted that these findings are subject to five limitations: 1) the results might overestimate actual breast cancer screening rates, 2) the results might not be representative of all women since the survey was conducted by telephone, 3) the responses are self-reported and not confirmed by medical records review, 4) the survey response rate was low, and 5) the results might not represent the entire U.S. population because the data only included states from the Women's Health Module.
Additionally, the editors commented that the decline in screening from 2000 to 2005 suggests a need for more careful monitoring because mammography screening every 1 to 2 years can significantly reduce breast cancer mortality.
Study Describes How Virus Evades Body's Defenses
A new study describes how a virus that causes T-cell leukemia and lymphoma evades one of the body's natural defense mechanisms. The study found that an enzyme that would normally inhibit viral replication is excluded from virus particles by human T-cell leukemia virus type 1 (HTLV-1). Resistance to the enzyme, called APOBEC3G or hA3G, may contribute to the persistence, dissemination, and potentially lethal nature of the virus.
Dr. David Derse of NCI's HIV Drug Resistance Program in the Center for Cancer Research in Frederick, MD, and his colleagues reported their findings online in the Proceedings of the National Academy of Sciences during the week of February 5. HTLV-1 infects 20 million people worldwide and is endemic in southern Japan, the Caribbean, and Africa. Most cases in the U.S. are found in the Southeast. Approximately 1 in 1,500 infected individuals develops HTLV-1-associated leukemia each year, usually decades after the initial infection.
Several human and nonhuman viruses that cause cancer or AIDS are susceptible to hA3G-mediated destruction. Some viruses have adapted ways to avoid this defense mechanism, however. Both HTLV-1 and the AIDS virus (HIV-1) are known to infect T lymphocyte white blood cells, and each has developed a different way of thwarting the antiviral effects of hA3G. When hA3G is incorporated into viral particles, it can start a process that will degrade and deactivate the virus itself.
"Our ultimate goal is to try to find a way to block the HTLV-1 virus from being active in the body," said Dr. Derse. "But, before we can do that, we must have a better understanding of how the virus evades the natural defenses in the cell that should be fighting off infection."
Future studies will investigate how hA3G gets packaged into the virus particle. "The next step will be to look at other viruses in relation to HTLV-1 and examine the mechanisms for evading the body's natural defenses," said Dr. Derse.
Brain Region Involved in Smoking Addiction Identified
Despite modern interventions, cigarette smoking remains difficult to quit, and relapse after an attempt at smoking cessation is common, in large part due to the many regions of the brain that play a role in addictive behavior. A new study from the University of Iowa published in the January 26 Science has identified a region of the brain - the insula - that may play an important role in the conscious urge to smoke and provide a potential target for new antismoking therapies.
Researchers compared 19 smokers who had experienced brain damage that included the insula with 50 smokers who had damage to other parts of the brain. They specifically assessed disruptions of smoking addition - cessation of smoking within 1 day of experiencing brain damage, a loss of the urge to smoke, ease in quitting, and lack of relapse to smoking.
Patients with damage to either the left or the right insula were significantly more likely to experience disruption of smoking addiction than those with damage to other regions. Twelve of the 13 patients who quit smoking after damage to the insula reported a disruption of smoking addiction, compared with only 4 of the 19 patients who quit smoking after damage to other regions of the brain. Damage to regions other than the insula was not significantly associated with disruption of smoking addiction.
The experience of their patients "suggests that the insula plays a role in the feeling that smoking is a bodily need," explained the authors. "Our findings suggest that therapies that modulate the function of the insula will be useful in helping smokers quit."
Radiation Fails to Add Benefit in Localized Lymphoma
Following chemotherapy for localized aggressive lymphoma, many clinicians have used radiotherapy targeted at the area near the tumor on the principle that better local control of disease will yield better outcomes. However, a European trial reported early online this week in the Journal of Clinical Oncology has shown that the addition of radiotherapy does not improve either event-free or overall survival.
The study included 576 patients who were randomly assigned to receive either CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy alone or CHOP and localized radiotherapy. Event-free and overall survival did not differ between the two groups of patients. Writing for the Groupe d'Etude des Lymphomes de l'Adulte (GELA), lead author Dr. Christophe Bonnet at the Centre Hospitalier Universitaire in Liege, Belgium, said that GELA has decided "to abandon radiotherapy as first-line treatment of localized aggressive lymphoma."
The GELA trial, known as GELA LNH 93-4, is the fourth randomized trial to compare chemotherapy alone with chemotherapy followed by radiation therapy in patients with stage I-II aggressive lymphoma. Overall, these trials have failed to support a role for radiotherapy in patients with localized aggressive disease.
In an accompanying editorial, however, Drs. Andrea Ng and Peter Mauch from the Dana-Farber Cancer Institute point out that CHOP chemotherapy in combination with the monoclonal antibody rituximab is the current standard of care for this disease. They state further that the most informative trial to clarify the role of radiation therapy in localized aggressive lymphoma will be one that compares CHOP plus rituximab followed by radiation therapy or no additional treatment.
IP Chemo Diminishes Well-Being in Ovarian Cancer Patients
A recent randomized phase III trial comparing intravenous (IV) plus intraperitoneal (IP) chemotherapy with IV chemotherapy alone in women with stage III epithelial ovarian cancer found that IP treatment significantly lengthened progression-free and overall survival. The researchers from the Gynecologic Oncology Group (GOG) also assessed the health-related quality of life (HRQOL) of participants during the trial.
Study results appearing in the February 1 Journal of Clinical Oncology indicate that women in the IP arm of the trial experienced more adverse side effects for a longer period of time than the women in the IV arm.
GOG researchers randomly assigned 429 patients to either the IV or IP chemotherapy treatment group between March 1998 and January 2001. Among this group, 415 were eligible to participate in the patient-reported HRQOL assessment. Researchers evaluated physical and functional well-being, ovarian cancer symptoms, neurotoxicity (Ntx), and abdominal discomfort (AD) at four time points: before random assignment, before chemotherapy cycle 4, 3 to 6 weeks after treatment, and 12 months after treatment.
While all women in the study reported negative side effects from treatment, women in the IP treatment group reported significantly worse physical and functional well-being before chemotherapy cycle 4 and 3 to 6 weeks after treatment. Women in this group also reported significantly worse AD before cycle 4 and significantly worse Ntx 3 to 6 weeks and 12 months after treatment. However, only the Ntx symptoms remained significantly greater for IP patients 12 months after treatment.
The study's authors wrote, "This HRQOL cluster, as well as patient-reported outcomes of Ntx and AD, should be targeted in future trials not only to evaluate treatment arm differences, but also to measure a patient's responsiveness to new supportive care strategies or surgical techniques aimed at making IP therapy more tolerable."