The P&S Journal: Spring 1998, Vol.18, No.2
Breast Cancer Radiation Treatment Raises Risk for Esophageal Cancer
Radiation treatment for breast cancer slightly raises a woman's long-term risk for esophageal cancer, according to findings published in the Jan. 15, 1998, issue of the Annals of Internal Medicine.
That does not suggest that patients should avoid lumpectomy and radiation, the standard therapy for early-stage breast cancer. Rather, physicians should be especially alert to symptoms suggestive of esophageal cancer in patients who have received radiation treatment, says the principal investigator, Dr. Habibul Ahsan, assistant professor of clinical public health. This is particularly important for patients who smoke cigarettes or drink alcohol, the two major risk factors for esophageal cancer.
The researchers examined the records of more than 220,000 breast cancer patients diagnosed between 1973 and 1993. Ten or more years after diagnosis, irradiated patients were roughly four to five times more likely to develop esophageal cancer than non-irradiated patients or women in the general population, according to Dr. Ahsan and his co-investigator, Dr. Alfred Neugut, associate professor of clinical medicine and public health. This is the first study to link radiation therapy for breast cancer with an increased risk for esophageal cancer.
In an earlier study, the researchers demonstrated that breast cancer irradiation raises one's risk for lung cancer. The risk was substantially higher among patients who smoked. The same pattern may hold true with esophageal cancer, says Dr. Neugut. In the lung cancer study, the effect of smoking turned out to be multiplicative. That is, you ended up with 40 times the risk if you were both a smoker and had radiation therapy. With esophageal cancer, the combined effect of irradiation and smoking may turn out to be even more dramatic. We don't know that yet. We're just starting a study that will give us some answers in a couple of years. The researchers also plan to analyze the effect of radiation dosage, alcohol consumption, and body mass index on the incidence of esophageal cancer.