Relationship between the Computed Tomography - Measured Initial Primary Tumor Volume, Urine VMA Level and Stage in Neuroblastoma Patients

Abstract

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 (CTPTV) 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 CTPTVs were calculated. The correlation between urine VMA level and CTPTV was assessed. The differences in CTPTVs 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 CTPTV. Finally, a comparison of demographic characteristics and stage between various CTPTV ranges (< 35 and ≥ 35 cm3) was performed. Results: A moderate correlation was observed between urine VMA level and CTPTV in patients with neuroblastoma (r = 0.673). The median CTPTVs 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 CTPTV was urine VMA level. When the urine VMA level increases 1 mg every 24 hours, the CTPTV will increase 4.85 cm3. Among the patients with a CTPTV ≥ 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 CTPTV < 35 cm3. Additionally, all patients with a CTPTV ≥ 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 CTPTV. A CTPTV ≥ 35 cm3 may therefore be used as an indicator of advanced tumor stage in neuroblastoma.