Application of the apparent diffusion coefficient in preoperative assessment of the proliferative potential of spinal tumors

Abstract

Objective. To analyze and compare the measured values of apparent diffusion coefficient (ADC) in tumors of the spinal canal with cell density and Ki-67 index of proliferative activity. Material and Methods. The study included diffusion-weighted MR images of 36 patients with different types of tumors of the spinal ca- nal. In the morphological study of tumors, the degree of malignancy according to the WHO classification, the value of the Ki-67 index, and cell density were assessed. Results. The average ADC of the extradural tumors G = I–II and G = III–IV was 1390.0 ± 94.8 mm2/s and 821.3 ± 111.1 mm2/sec, respectively. For intradural extramedullary neoplasms G = I–II, the ADC was 1328.7 ± 172.1 mm2/sec, for G = III – 957.6 ± 50.7 mm2/sec. Intramedullary tumors G = I–II had an average ADC value of 1604.6 ± 28.7 mm2/sec, and tumors G = III – 1066.5 ± 74.2 mm2/sec. For extradural tumors G = I–II, the Ki-67 index varied from 2 to 4 %, and for tumors G = III–IV – from 12 to 27 %; in the group of intradural extramedullary tumors G = I–II – from 1 to 5 %, for tumors G = III – from 7 to 11 %; for intramedullary tumors G = I–II – from 2 to 6 %, and for G = III tumors – from 7 to 19 %. Conclusion. The diffusion-weighted MRI with ADC counting can be used as an additional non-invasive method for preoperative evalua- tion of the proliferative potential of a number of spinal canal tumors.

Keywords

• spinal canal tumors
• diffusion-weighted mri
• apparent diffusion coefficient
• diffusion-weighted image
• cell density
• ki-67 index