Importance
Irradiation treatment for pediatric patients with neuroblastoma represents a major challenge due to the pediatric dose limits for critical structures and the necessity of sufficient dose coverage of the clinical target volume for local control.
Objective
To investigate dosimetric differences between tomotherapy (TOMO) and volumetric‐modulated arc therapy (VMAT) as retroperitoneal radiotherapy for children with neuroblastoma.
Methods
Eight patients who received retroperitoneal radiotherapy for neuroblastoma were selected for comparison of TOMO and VMAT treatment plans. The D
min
, D
max
, D
mean
, D
95
, D
2
, and D
98
of planning target volume (PTV), conformity index (CI), heterogeneity index (HI), and organs at risk (OARs) parameters were compared. Delivery machine unit (MU) and image‐guide radiotherapy solution results were also compared.
Results
All patients received a cumulative dose of 19.5 Gy to the PTV. VMAT showed higher CI (0.93 ± 0.02), compared with TOMO (0.87 ± 0.03,
P <
0.001). Notably, the average PTV HI was significantly better using TOMO (1.05 ± 0.01) than VMAT (1.08 ± 0.02,
P =
0.003). Compared with VMAT, the D
min
, D
95
, and D
98
all exhibited increases in TOMO; D
max
variation was less than 1% in TOMO. The D
0.1cc
for the spinal cord and D
2cc
for the small intestine were better in TOMO in terms of OARs. However, TOMO had more MUs and required a longer delivery time.
Interpretation
Both planning techniques are capable of producing high‐ quality treatment plans. TOMO is superior for PTV coverage, but inferior for CI. TOMO requires extra treatment time; its cost is greater than the cost of VMAT.