MRI reliability in pediatric abdominal lymph node metastases?

Although positron emission tomography-computed tomography (PET-CT) is an effective imaging method used in the detection of lymph node metastases, repeated imaging increases X-ray exposure, especially in pediatric patients. Magnetic resonance imaging (MRI) may detect abdominal lymph nodes and provide subtle anatomic detail, and functional information without radiation.

To evaluate the reliability of MRI in detecting lymph node metastases in pediatric abdominal malignancies and to determine whether X-ray dose can be reduced by comparing its effectiveness with PET-CT.

Patients aged <18 years, diagnosed with abdominal malignant solid lesions between January 2015 and 2022 were included in this retrospective single-center study. A total of 14 A total of 14 different anatomic locations were defined for lymph nodes in MRI and PET-CT examinations. Cohen's kappa test was used to evaluate the consistency between PET-CT and MRI. P < 0.05 was considered statistically significant.

In total, 25 patients (18 [72%] girls, 7 [28%] boys; mean age = 9.32 ± 16.9 years; age range = 1-18 years) with abdominal solid malignant tumors were included. The reliability of MRI and inter-observer reliability differed depending on the location of the lymph nodes. The reliability was almost perfect for the internal iliac (k = 0.915), porta hepatis, and aortocaval lymph node stations, while fair reliability was observed for the mesenteric lymph nodes (k = 0.525).

The results showed that MRI was as reliable as PET-CT in detecting some intra-abdominal metastatic lymph nodes, while its reliability was lower in some lymph node stations.