A colonic mass cannot be judged as benign or malignant on the basis of its size. It can be judged according to whether the shape of the mass is regular or not, the degree of differentiation, the way of growth and other aspects. 1. Shape, if the shape of the colon mass is irregular, and the boundary with other tissues is not clear, it may be malignant. On the contrary, if the shape of the mass is regular and the boundary is clear, then the mass may be benign. 2. The degree of differentiation, the best way to determine the benign and malignant nature of the mass is to do pathological examination, to clarify the degree of differentiation of the mass, as well as heterogeneity. Benign masses are well differentiated and have low heterogeneity, while malignant masses are relatively poorly differentiated and have high heterogeneity. 3. growth mode, if the growth of the mass is exogenous growth, and slow growth rate, it is mostly benign; if the growth mode is erosive, infiltrative growth, fast, it is mostly malignant. In conclusion, to determine the benign or malignant nature of colonic masses, it is necessary to do a pathologic biopsy, combined with clinical symptoms and other test results. If you feel unwell, please seek immediate medical attention for further diagnosis.