Specialists have found that a combination of chemotherapy and radiotherapy extends survival in patients with head and neck tumors. However, there is a downside to the treatment, especially radiotherapy. Cellular absorption of ionizing radiation generates toxic free radicals and leads to faulty repair of DNA breaks and cell death. Responses to radiotherapy occur in time frames of hours (nausea, vomiting), days (erythema), weeks (bone marrow supression), months (fibrosis), and years (carcinogenesis). Among survivors of the cancer itself, late effects on "bystander" organs -- such as the thyroid and salivary glands -- have become increasingly prevalent, with secondary malignancies and infections boosting the levels of sickness and death.
Physicians have noted that after neck irradiation, long-term injury commonly occurs in the carotid arteries. Atherosclerotic and thrombotic complications have drawn the most attention. For example, in a study of 910 patients who survived at least five years after irradiation of head and neck tumors, stroke occurred in about six percent and clinically significant carotid stenosis was observed in 17 percent.
A New Study
A new study examines three cases where symptomatic baroreflex failure occurred apparently as a late consequence of neck irradiation. The baroflex is originating from the stimulation of the carotid sinus baroreceptors and plays an important role in maintaining proper blood pressure.
Results Being Presented At Upcoming Conference