Twenty percent of British adult survivors of childhood cancer smoke despite hazards

Jul 29 2008

Twenty percent of British adult survivors of childhood cancers are current smokers, and nearly a third have been regular smokers at some point in their lives, according to a study in the July 29 online issue of the Journal of the National Cancer Institute.

Adult survivors of childhood cancer are at increased risk of developing cardiovascular disease, lung problems, and second malignancies, relative to the general public. These increased risks are due to long-term effects of the original cancer and its treatment, as well as to genetic conditions that predispose the survivors to multiple cancers. Smoking would be an additional source of risk for this population.

To learn what fraction of adult survivors are current smokers or have smoked regularly in the past, Clare Frobisher, Ph.D., of the University of Birmingham, UK, and colleagues sent surveys to all those who could be contacted from among 14,836 eligible survivors of childhood cancer in the National Registry of Childhood Tumors. To be eligible for the study, survivors had to have been diagnosed with their primary cancer between 1940 and 1991 and be aged 16 years or older at the time of the survey. Of those survivors, 10,326 returned completed study questionnaires and were included in the current analysis.

Of the respondents, 20 percent were current regular smokers and 29.8 percent were regular smokers at some time in their life prior to the completion of the survey. When the researchers analyzed the responses by tumor site, they found that survivors of central nervous system cancers or heritable retinoblastoma were least likely to smoke, while survivors of Wilms tumor, Hodgkin lymphoma, or soft tissue sarcomas were most likely to report being a regular current smoker. Individuals who had been treated with radiation or chemotherapy were less likely to smoke than those who had not received that type of therapy. Also, those who did not have regular hospital follow-up appointments were more likely to smoke than those who did.

The rate of current smoking in the survivors was approximately half of the rate in the general British population. The socioeconomic factors that are associated with an increased risk of smoking in the general public, though, are the same as those in the adult survivor group, including manual occupations compared with managerial or professional work, lower educational attainment, and being widowed, divorced, or separated.

The relatively high rate of smoking in survivors of Wilms tumor, Hodgkin lymphoma, and soft tissue sarcomas is concerning because previous research suggests that these survivors are at a particularly high risk for second malignancies.

The researchers conclude that although the rate of smoking in adult survivors of childhood cancer is lower than in the general public, further efforts are needed to reduce the smoking prevalence in this group. In general, any program of clinical follow-up for survivors of childhood cancer should include advice on the health risks of smoking, the authors assert. "Smoking cessation interventions would be more appropriate for the [British Childhood Cancer Survivor Study] cohort than smoking prevention interventions because a high proportion of the survivors were older than the age at which most individuals initiate smoking (i.e., ¡Ü20 years of age)," the authors write.

In an accompanying editorial, Karen Emmons, Ph.D., of the Dana-Farber Cancer Institute and Harvard School of Public Health in Boston notes that the new findings are remarkably similar to data from the U.S. Childhood Cancer Survivor Study, in which 17 percent of adult survivors reported being current smokers and 28 percent reported being ever smokers. The good news is that the rates are lower than the general public. The bad news, according to Emmons, is that for the survivors who do smoke, the habit is likely to exacerbate the already negative long-term effects of cancer treatment.

More needs to be done to reduce the rate of smoking in adult cancer survivors, Emmons writes, noting that fewer than half of the survivorship programs in the U.S. currently offer smoking cessation services. Beyond just treating this issue specifically, however, Emmons argues that broader efforts are needed to improve the socioeconomic pressures and social disadvantages that encourage smoking and reduce public health. "It is time to think well beyond our disciplinary boundaries and implement interventions that we know are efficacious, such as provider-delivered counseling and pharmacotherapy, and seek solutions for the social conditions that serve as a trajectory for a lifetime of smoking," she writes.