- Maury Breecher
- Cancer Epidemiology, Biomarkers & Prevention (Vol. 10: 823-829)
Lower Second Tumor Occurrence in Head and Neck Cancer Patients who have never smoked
Patients with head and neck cancer are known to have a significant risk of developing a second primary cancer (SPT), especially in the head and neck area. The good news, however, is that former smokers and those who have never smoked develop fewer of these second primary tumors than active smokers, according to a report in Cancer Epidemiology, Biomarkers & Prevention (Vol. 10: 823-829).
This is first large-scale randomized study to evaluate the impact of smoking history on the development of SPTs and recurrence in patients with head and neck cancers.
Smoking Increases Second Cancer Risk
“Controversy has existed about the role of continued smoking in the development of SPTs, but our study provides the first objective evidence proving that continued smoking increases the risks of SPTs,” Edward Kim, MD, an author of the study, tells ACS News Today. Recurring tumors are the return of an original tumor. SPTs are new tumors with a different histology (different cell types) which occur at locations anywhere in the body greater than two centimeters away from the site of the first tumor, says Kim.
Active Smokers Have Highest Risk
“Significantly different smoking-related SPT development rates were observed in current, former, and never-smokers,” Kim says. “The results showed significantly higher SPT rates in active smokers versus patients who had never smoked and showed former smokers had a survival advantage over active smokers.” “This is important information because it reinforces the idea that individuals who develop cancer — in this case head and neck cancer — are at increased risk of developing second primary tumors if they are active smokers,” says Michael Thun, MD, vice president of epidemiology and surveillance research for the American Cancer Society. Those tumors pose substantial risks to life.” Thun points out that surgery and radiation therapies are usually effective therapies in early-stage head and neck cancer. “However, secondary tumors cause much of the mortality that occurs in this type of cancer,” Thun says. “That’s why the development of SPTs is something that we want to prevent. The study shows that even in long-term smokers who had already developed one cancer, quitting is beneficial in reducing the risk of occurrence of SPTs. Thus quitting smoking provides a survival advantage to head and neck cancer patients.”
The researchers studied 1,191 cancer patients who had been treated for an initial cancer in the head and neck area, and who, at the time of their entry into the study, were disease free. The patients were randomly assigned to receive either a medication or a placebo — a medication with no active ingredient—to determine if the medication under study decreased the recurrence of head and neck cancers after primary treatment, or the later development of SPTs. SPTs developed in 172 patients at various sites throughout their bodies. Of those patients, 121 (70.3%) were determined to have smoking-related tumors located in the head and neck, esophagus, lungs, or bladder. Of the active smokers, 4.2% developed second primary tumors compared to 3.2% of former smokers and 1.9% of the never smokers. The remaining 51 cases included cancers determined not to be tobacco-related.
The study is continuing, with patients receiving either the placebo or the experimental medication, a retinoid called 13cRA (taken from the A vitamin). Researchers hope the medication will have a significant impact on preventing the development of SPTs. “The final results of this trial will help tremendously in establishing the optimal, post therapeutic intervention in this population,” says Kim. “Should the results be positive, a new, unequivocal standard of care will be set for prevention therapy.”