Palliative radiotherapy for children: Symptom response and treatment‐associated toxicity according to radiation therapy dose and fractionation

Abstract

Background/objectives Radiotherapy is an effective palliative treatment in advanced cancer. Shorter palliative treatment courses are recommended for adults, though pediatric data addressing treatment efficacy and toxicity according to radiation therapy (RT) dose and fractionation are limited. Design/methods Total 213 patients aged 21 years or younger receiving 422 palliative radiotherapy treatment courses from 2003 to 2016 were included. Symptom response and treatment‐associated toxicity were recorded and analyzed in relationship to demographic and treatment variables. Results Common diagnoses included sarcoma (32.5%), neuroblastoma (24.9%), leukemia/lymphoma (14.9%), and central nervous system tumors (10.9%). The most common indication for treatment was pain (46.7%). Patients received a median of 10 fractions, 2.5 Gy dose per fraction, and 21 Gy total dose. Number of RT fractions was five or less in 166 (39.3%), six to 10 fractions in 117 (27.2%), and 10 or more fractions in 139 (32.9%) of courses. Complete or partial pain relief was achieved in 85% (151 of 178 evaluable patients), including 77.8% receiving five or less fractions and 89.6% receiving more than five fractions. Highest toxicity was grade 1 in 159 (38.9%), grade 2 in 26 (6.4%), and grade 3 in two (0.5%) treatments. On multivariable analysis, RT delivered 30 or more days from death (OR 12.13, 95% CI: 2.13–69.2, p = .005) and no adjuvant chemotherapy (OR 0.14, 95% CI: 0.03–0.54, p = .005) were significantly associated with pain response, and five or less fractions were significantly associated with lower toxicity (OR 0.24, 95% CI: 0.06–0.97, p = .045). Conclusions Palliative RT courses of five or less fractions result in high rates of pain control and are associated with low toxicity in pediatric patients with cancer.

Thirty-day mortality as a metric for palliative radiotherapy in pediatric patients

“…Of polled pediatric oncologists, 83% stated the theoretical concern for potential treatment toxicity was the most frequently reported barrier to delivery of palliative RT [14]. This is discordant with most available data which report acceptable toxicity levels with excellent response rates [19, 21▪▪]. However, it appears that palliative radiation is more effective when delivered prior to the last 30 days of life than within the last 30 days, likely because of the time required to elicit a response from RT.…”

“…The article was excluded if the studied population contained patients over the age of 21. This search revealed three studies that reported their institutional rates of 30DM in pediatric patients receiving RT with the first being published as recently as 2015 (Table 1) [13, 21▪▪, 22]. Similar to adult patient data, 30DM rates among children vary greatly based on institutional practices, and 30DM ranged from 0.7% to 30%.…”

“…Despite less frequent utilization of palliative RT among pediatric patients, some data appear to indicate these patients have excellent rates of symptom response (72–100%) when radiation is used early to palliate pain, dyspnea, and neurologic symptoms [21▪▪,22,23]. However, when assessing symptom response near the EOL, these success rates decrease dramatically as demonstrated in two retrospective studies (Table 1).…”

“…Among those who died within 30 days of receiving RT, the success rate of pain palliation similarly decreased; however, the response rates among these two cohorts were not specifically reported. On multivariate analysis, radiation delivery >30 days from death (OR 12.13, 95% CI: 2.12–69.2, P = 0.005) and chemotherapy (OR 0.14, 95% CI 0.03–0.54, P = 0.005) were the only factors associated with higher palliation success [21▪▪].…”

Comment on: Palliative radiotherapy for children: Symptom response and treatment‐associated toxicity according to radiation therapy dose and fractionation

“…We read the article titled "Palliative radiotherapy for children: Symptom response and treatment-associated toxicity according to radiation therapy dose and fractionation" with great interest. 1 There has been a paucity of data regarding the optimal palliative radiotherapy (RT) schedule for the pediatric population and this largest study in the literature could shed light on this subject. However, there are some points to be clarified.…”