A histopathologic study of 65 resected malignant lesions of the pancreas was done to search for a histologic predictor for the presence of extra‐pancreatic neural plexus involvement by carcinoma cells. Extra‐pancreatic neural plexus invasion by pancreas carcinoma cells, p/x(+), was detected in 28 of 65 cases (43).plx(+) was not significantly associated with tumor location, tumor size, histologic type, or lymph vessel invasion (ly) by carcinoma cells but was significantly associated withrpe.P/x(+) was also significantly associated with mixed moderate and severe degrees of intra‐pancreatic neural invasion (ne2/ne3group), but not with mixed no and slight degrees (ne0/ne, group). However, fourteen p/x(+) cases were excluded in thene2/ne3group; they were found in the ne, group. Therefore,nefactors appear to have a certain but limited usefulness for the prediction ofplx(+). When a perineural invasion by tumor cells was found within the pancreas but outside of the major mass of cancer, it was designated “intra‐pancreatic, extra‐tumoral perineural invasion (nex)”. The presence of nex(+) was found in 37 cases, in which 24 out of the 28p/x(+) cases (85.7) were included. A statistically significant association was found betweenp/x(+) and nex(+). In particular, 12 out of the 14p/x‐ positive ne, cases werenex(+). In ne, cases, 33.3 (14/42) werep/x(+), whereas inne1andnex(+) cases, 60 (12/20) werep/x(+). There was a statistical significance between these two figures (p<0.05). Thus, nex(+) appears to be a useful indicator forp/x(+), particula
展开▼
