Clinicopathological and molecularbiological study of perineural invasion in pancreatic cancer.

目的：周围神经侵犯被认为是胰腺癌局部复发的一个相关因素。我们对胰腺癌的神经周围浸润进行了病理和临床检查。方法：观察24例手术切除的胰腺癌患者神经周围浸润程度、分化程度、间质结缔组织、淋巴结转移程度与生存率的关系。6例感兴趣病例连续制作5 μm连续切片（n=1072）。结果：周围神经侵犯17例（70.8%；ne0-7例；ne1-6例；ne2-9例；ne3-2例）。5例乳头状癌中3例未见神经周围浸润，而14例中分化癌中有12例可见神经周围浸润。ne0组生存率较其他组好，3年生存率为57.1%。2例神经周围间隙癌腺体不连续发展。结论：周围神经侵犯是胰腺癌的重要预后因素，随着肿瘤未分化而增加。即使手术时胰腺边缘没有癌细胞，癌细胞也可能进一步扩散到未癌变的胰腺或腹膜后。可能需要充分的神经丛解剖或术中放射治疗。

Purpose : Perineural invasion is regarded as a factor associated with local recurrence of pancreatic cancer. We examined perineural invasion of pancreatic cancer pathologically and clinically.Method : In 24 cases of surgically resected pancreatic cancer, correlations among the degree of perineural invasion, differentiation, interstitial connective tissue, lymph node metastasis and survival rate were examined. Consecutive 5-μm serial sections (n=1072) were made in 6 interesting cases.Results : Perineural invasion was observed in 17 cases (70.8% ; ne0-7 ; ne1-6 ; ne2-9 ; and ne3-2 cases). Perineural invasion was absent in 3 of 5 cases of papillary carcinoma, but was observed in 12 out of 14 cases of moderately differentiated carcinoma. The survival rate for ne0 was better than that of the other groups, the 3-year survival rate being 57.1%. Cancer glands in the perineural space had developed discontinuously in 2 cases.Conclusions : Perineural invasion is an important prognostic factor in pancreatic cancer, increasing as the cancer becomes undifferentiated. Even if there are no cancer cells at the margin of the pancreas at the time of surgery, the cancer may spread further to the non-cancerous pancreas or retroperitoneum. Sufficient dissection of the neural plexus or intraoperative radiation may be required.