[The expression of neural cell adhesion molecule (NCAM), neural invasion and recurrence patterns in rectal cancer--a...

Neural invasion may be one of the main causes of local recurrence, but its mechanism has not been sufficiently clarified. We previously reported that the expression of NCAM on cancer cells was correlated with neural invasion in pancreatic cancer. In this study, we examined the neural affinity of rectal cancer cells and the relationship between neural invasion and recurrence patterns of rectal cancers. A total of 64 rectal adenocarcinoma were examined. Specimens from 17 patients (27%) revealed perineural invasion. The incidence of neural invasion increased with the frequency of venous invasion and the degree of lymph node metastasis, but not significantly. The incidence of the expression of NCAM in rectal cancer cell was 45.3 percent. Neural invasion of rectal carcinoma was significantly related to the expression of NCAM (p < 0.05). NCAM immunocytolocalization was classified into the focal type, and the diffuse type. Concerning the recurrence type, 8 of 9 cases that developed local recurrence showed either presence of neural invasion or expression of NCAM. Liver metastasis was associated with absence of neural invasion or NCAM expression. The expression of NCAM may contribute to local recurrence, whereas the absence of NCAM may predict liver metastasis.