Relationship between the computed tomography-measured initial primary tumor volume, urine VMA level and stage in neuroblastoma patients

Background: Nowadays, volumetric data acquisition has allowed for the accurate quantification of volumetric tumor burden. However, few studies have focused on the relationship between neuroblastoma tumor volume and relevant clinical parameters. Objectives: The purpose of this study was to investigate the relationship of initial computed tomography-measured primary tumor volume (CT_PTV) with 24-hour urine vanillylmandelic acid (VMA) level and stage in patients with neuroblastoma. Patients and Methods: This retrospective study included 24 patients. The patients’ age, gender, urine VMA levels and stage at diagnosis were collected, and the CT_PTVs were calculated. The correlation between urine VMA level and CT_PTV was assessed. The differences in CT_PTVs with respect to age of the patients (≤ 1.5 and > 1.5 years old), gender, urine VMA levels (≤ 9.8 and > 9.8 mg/24 hours) and stage (stage 4 and non-stage 4) were analyzed. Multivariate linear regression was conducted to estimate the effect of age, gender, urine VMA level, and stage at diagnosis for CT_PTV. Finally, a comparison of demographic characteristics and stage between various CT_PTV ranges (< 35 and ≥ 35 cm³ ) was performed. Results: A moderate correlation was observed between urine VMA level and CT_PTV in patients with neuroblastoma (r = 0.673). The median CT_PTVs were significantly larger in patients with urine VMA > 9.8 mg (P = 0.03) and in patients who were diagnosed with stage 4 (P = 0.002). The most effective variable for CT_PTV was urine VMA level. When the urine VMA level increases 1 mg every 24 hours, the CT_PTV will increase 4.85 cm³. Among the patients with a CT_PTV ≥ 35 cm³, the median age was significantly higher (P = 0.011), and median urine VMA level was significantly higher (P = 0.001) than in patients with a CT_PTV < 35 cm³. Additionally, all patients with a CT_PTV ≥ 35 cm³ had stage 4 disease at the time of diagnosis (P = 0.001). Conclusion: A moderate positive quantitative correlation was observed between 24-hour urine VMA levels and initial CT_PTV. A CT_PTV ≥ 35 cm³ may therefore be used as an indicator of advanced tumor stage in neuroblastoma.