[Long term follow-up to identify the rectal potentially malignant nodules in female by digital rectal examination]

Objective: To investigate the characteristics of the rectal potentially malignant nodules in female by digital rectal examination (DRE). Methods: Retrospectively, we collected the medical information and follow-up of rectal nodules cases diagnosed as benign by DRE during the health check-up in our hospital from Jan 2002 to Dec 2015. All nodules were recorded position, size, shape, hardness and mobility. Statistical analysis was performed to select the potentially malignant cases of postoperative pathological diagnosis and disappeared nodules followed up by DRE. Results: We followed up 190 cases with 195 nodules finally. Twenty-five cases were potentially malignant, including 14 (56.0%) of polyps, 9 (36.0%) neuroendocrine tumors, and 2 (8.0%) gastrointestinal stromal tumors. The sizes of the nodules were <1.0 cm of 23 (92%) cases, among them 12 (48%) cases were ≤0.5 cm, while 23 nodules (92%) were mobile.There were two cases of potentially malignancy in both groups with enlarged and unchanged modules.There were 69 cases of nodules disappeared during follow-up. The size of these nodules were <1.0 cm, 63(91.3%) cases ≤0.5 cm. while 32 (46.4%) were fixed. The univariate analysis showed that the detection rate of potentially malignant group was higher than that of disappeared group in age (t=-3.691, P<0.01), size (Z=-3.537, P<0.01) and mobility (χ(2)=13.315, P=0.001). On multivariate analysis, the risk of potentially malignant increased with age (OR=2.324, P=0.004) and the size (OR=1.537, P=0.003) of the nodules. The risk of fixed small nodules (OR=0.081, P=0.020) was lower than that of the mobile nodules. All the above differences were statistically significant. Conclusions: The risk of potential malignancy increased with age and the size of the nodule in female. The risk of fixed small nodules, which were regard as malignant, was lower than that of mobile nodules. Potential malignancy should exclude in small, enlarged or unchanged nodules during follow-up.