Diffusion weighted imaging (DWI) plays a crucial role in diagnosis and prognosis of cancerous diseases. Proper demarcation of tumour on DWI is therefore necessary for qualitative assessment as well as quantitative image analysis like ADC or IVIM. Manual demarcation of tumour on each DWI slice is time consuming, prone to error and hard to reproduce. Automated and semi-automated algorithms were implemented and tested to segment bone tumours specifically on DWI. Experimental results reveal that semi-automated Active-Contours performed tumor segmentation better than other methods with acceptable levels of accuracy with considerable less time and manual effort.