Predictive toxicity markers in elderly patients underwent RT and managed by an oncogeriatric model

ABSTRACT

Purpose or Objective A growing number of elderly patients every year is treated with radiation therapy (RT), but little is known about side effects and outcome of irradiation in this potentially frail population. The identification of predictive factors of toxicity and frailty could offer a personalized treatment approach, thanks also to a multidisciplinary management of patients with increased risk of adverse outcomes. In this study we investigated the correlation of patient parameters with acute toxicities in elderly aged > 75 years treated with curative RT. Materials and Methods A prospective observational study was designed in our Center for patients with > 75years, candidate for curative RT. To these patients the radiation oncologist submitted the Geriatric 8 questionnaire (G8q) before and at the end of RT. Patients with G8 score < 14 were then evaluated by a multidimensional geriatric assessment, investigating cognitive (MMSE, GDS), functional (ADL, IADL, Tinetti) and nutritional (MNA short) domains, to define the frailty phenotype. In this setting, we retrospectively analyzed parameters like body mass index (BMI), number of comorbidities, total blood count, neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR) and basal G8 score, and correlated these parameters to acute toxicity. Results G8q was administered to 150 patients from December 2019 to April 2021. In this study we included 98 patients who started and completed RT in our Unit in this period. Of them, 38 (38.8%) had a baseline G8 score < 14 (range 4-14) and 23 agreed to underwent a multidimensional assessment, while 15 could not be evaluated due to COVID-19 dispositions or their refusal. Eleven patients resulted fit, while 12 patients were classified as vulnerable. Acute toxicity grade was < grade 2 in 67 patients (68.4%) (Table 1). We evaluated associations between BMI, number of comorbidities, total blood count, NLR, PLR, G8 score and acute toxicity (Table 2). Total blood count, NLR, PLR and G8 score resulted not significantly correlated to toxicity. Instead, a higher BMI was associated with worse acute toxicity (p=0.031) considering the 31 patients reporting toxicity > grade 2, 17 patients were over-weighted (54.8%), 1 patient was under-weighted (3.2%). Overall, the 63.3% of population (62 patients) was over-weighted, with a median BMI of 26.3. (Table Presented) (Table Presented) Conclusion Although G8q considers under-weight as a possible responsible of frailty, our study suggested that attention should be paid to over-weight too, due to its prevalence in elderly patients. Furthermore our results suggested that in elderly patients > 75years the BMI correlates with worse acute toxicity, according to literature data. The 38.8% of patients needed a multidimensional evaluation;this approach resulted useful in order to obtain compliance to the treatment without increased toxicity. The study is still ongoing and further analysis will be done.