[MR imaging in patients with bone marrow metastases of neuroblastoma]

Sixty patients with neuroblastoma or ganglioneuroblastoma underwent MRI 87 procedures to detect and follow up bone marrow metastases. The detection of bone marrow metastases by MRI was evaluated with aspiration cytology. Relationships were investigated between bone metastases and bone marrow metastases that were morphologically classified as nodular and diffuse by MRI findings. The usefulness of MRI was also studied in evaluating the effect of chemotherapy. MRI showed bone marrow metastases in all of 17 patients, but aspiration cytology proved metastases in only 7 of 17. Bone metastases were proven by bone scintigraphy or bone X-ray in 5 of 15 patients, and only diffuse bone marrow metastases were accompanied with bone metastases. After or during chemotherapy, 10 patients were examined by MRI more than two times. Bone marrow metastases disappeared in 9, decreased in size in 3, did not change in one and recurred at another site in one. It was observed from MRI findings that in the early stage, bone marrow metastases are nodular, but along with progress of the disease, they become diffuse and invade the bone cortex. If chemotherapy was effective, bone marrow metastases were decreased in size or disappeared completely.