Elderly patients with lung cancer tolerate radiation therapy well
Until now, it was thought that older patients with lung cancer are more likely than younger patients to suffer from adverse effects of radiation therapy, such as esophagitis or pneumonitis. Currently, a clinical trial has produced unexpected results.
More than 65% of people who have been diagnosed with lung cancer are over 65 years old. However, because of their old age, there are often concerns about the use of aggressive therapy. The issue on what adverse effects of radiation therapy for lung cancer occurred in older people compared with younger patients is now investigated by Payla Soni and his colleagues from the University of Michigan in the city of Ann Arbor (J Thoracic Oncol 2017; online on February 1). To this end, radiology specialists evaluated the prospective data of 125 patients (a group of patients based on a sample) from 2004 to 2013, as well as a larger group of patients, which included 691 patients who received radiation therapy (Michigan Radiation Oncology Quality Consortium, MROQC). The risk of esophageal or pulmonary toxicity due to exposure was expected to increase with age.
However, completely opposite data were obtained. The way the incidence of esophagitis decreases with age is demonstrated by the following calculations made by Sony and his colleagues: A 70-year-old non-smoking patient with a good general state of health, who receives highly elevated radiation therapy in parallel with chemotherapy, becomes ill with esophagitis three times less than compared to him is a patient at the age of 50 years.
Even taking into account various factors, such as dosage, simultaneous chemotherapy, smoker status and general condition, a multivariate regression analysis of a group of selected patients showed a significantly smaller number of cases of esophagitis with increasing patient age. With each passing year of life, the risk ratio (RR) decreased by 0.92-0.93. In general, 39% of all patients in the selected group were diagnosed with esophagitis of the 2 degree, 11% - ≥ 3 degree. Higher toxicity rates have not been reported. In patients under the age of 70 years (82 patients), esophagitis was diagnosed in 48, i.e. 16%, and in patients aged ≥ 70 years (43 patients) - in 23, i.e. 2%.
A similar pattern was observed in the MROQC patient group. Here, 52% of patients were diagnosed with esophagitis of ≥ 2 degree and 1.9% - 3 degree and more. Of the 389 patients aged < 70 years, 55 or 2.1% were diagnosed with this disease, out of 302 elderly patients, it was detected in 47, i.e. in 1.7% of patients. Taking into account various impact factors, the risk ratio (RR) in this group of patients also decreased every year by 0.97-0.98. Age did not affect the occurrence of pneumonitis in any of the patient groups.
Obviously, with age, esophagitis is less common in patients with lung cancer who received radiation therapy. This relationship also remains significant when, for example, chemotherapy is taken into account, which can also contribute to the onset of esophagitis. However, according to Sonya and his colleagues, the prevention of esophagitis as a result of radiation therapy is not due to the patient’s age itself, but rather to an increasingly weaker perception of pain in this area, which decreases with each subsequent year of life, as has been indicated in previous studies. Despite the fact that the reason for this age feature can only be clarified in future studies, according to the authors, elderly patients with lung cancer in good general health should now be offered radiation therapy to the chest area in accordance with standard recommendations, since such patients obviously tolerate such treatment as well as younger patients.