Usefulness of the G8 Screening Tool in Determining Treatment Strategies for Definitive Radiotherapy of Esophageal Cancer in the Elderly

Abstract

<h3>Purpose/Objective(s)</h3> Recent clinical trials for chemoradiotherapy (CRT) in esophageal cancer, such as ARTDECO and CONCORDE used elective nodal irradiation (ENI). However, it is often difficult to perform standard CRT for the elderly in the real world, and also there is no clear consensus on the criteria for this decision. Recently the G8 screening tool for geriatric assessment has been attracting attention in the oncology field. This study aimed to investigate the relationship between the treatment strategy of definitive RT and the G8 score for esophageal cancer in the elderly. <h3>Materials/Methods</h3> We analyzed 81 esophageal cancer patients aged ≥65 years (27 aged ≤74 years, 26 aged 75-79 years, and 28 aged ≥80 years) who received definitive RT between 2018 and 2021. The G8 screening tool was performed at the first visit to the radiation oncology department. The treatment strategy was decided by a conference between the radiation oncologist and esophageal surgeon, and the G8 score was not used to determine the treatment strategy. Standard RT was defined as ENI and a total dose ≥50 Gy, and standard chemotherapy (ChT) was defined as two cycles of platinum (70 mg/m2) and 5FU (700 mg/m2 for 4 days) concurrently. Patients who underwent standard RT and standard ChT were defined as the standard group and the rest as the non-standard group. The Mann-Whitney U test was used to compare the two groups, and statistical significance was set at p<0.05. The Receiver Operating Characteristic (ROC) curve was used to calculate the cutoff value. <h3>Results</h3> The mean G8 scores by age were 12.7 (range: 7-17) for ≤74 years, 12.9 (range: 7-17) for 75-79 years, and 10.4 (range: 4.5-15) for ≥80 years, and significantly lower scores for ≥80 years, but no significant difference between ≤74 and 75-79 years. There were 26 patients in the standard group, of which only one was ≥80 years. In the patients ≤79 years, the G8 score was significantly higher in the standard group (mean: 13.9 points in the standard group and 11.6 points in the non-standard group) (p<0.01), but age was not significantly different between the standard and non-standard groups (p=0.94). The cut-off value of the G8 score calculated by the ROC curve was 13 points. In patients ≥80 years, 10 patients received CRT (1 standard ChT, 9 reduced ChT), and 15 of 18 patients in the RT alone group received only local RT. In the patients ≥80 years, the G8 score was significantly higher in the CRT group (mean: 12.5 points in the CRT group and 9.2 points in the RT group) (p<0.01), but age was not significantly different between the CRT and RT groups (p=0.08). The cut-off value of the G8 score calculated by the ROC curve was 12 points. <h3>Conclusion</h3> Our results suggest that the G8 screening tool may be useful in determining the treatment strategy of definitive RT for esophageal cancer in the elderly. Future investigation of the relationship between the G8 score and treatment outcomes is required.