Kunio Kameda

Expression of highly polysialylated neural cell adhesion molecule in pancreatic cancer neural invasive lesion

Neurotropism of pancreatic cancer is one of the hypotheses explaining neural invasion, which is one of the characteristics of pancreatic cancer. In these studies, we immunohistochemically examined neural cell adhesion molecules (NCAM), homophilic adhesion molecules expressed on the nerve cells, as a factor of neurotropism, in 15 pancreatic cancer operatively obtained, especially in neural invasive lesions. We also investigated the role of polysialic acid (PSA), which is attached to NCAM and related to the malignant potential of cancers. NCAM was detected in 66.7% of pancreatic cancers, and in all 9 cases with massive perineural invasion. In neural invasive lesions, however, there were perineurium and endoneurium, which do not express NCAM, between the cancer and nerve cells. PSA was also detected in the pancreatic cancers expressing NCAM. Moreover, PSA expression was stronger in the perineural invasive lesions than in the main tumor and was related to the cancer cell proliferation investigated by Ki-67 staining. It is unlikely therefore, that NCAM plays an important role in neurotropism. However, the NCAM expressed on the pancreatic cancer was attached to PSA, which itself plays an important role in the malignant potential of this disease.

Pancreatojejunostomy by Duct-Insertion Method: Clinical and Experimental Study

We have applied the duct-insertion method with complete drainage of pancreatic juice to patients with normal pancreatic tissue and an undilated pancreatic duct, and the duct-mucosal suture method to patients with hard pancreatic tissue and a dilated pancreatic duct. The safety and certainty of this duct-insertion method was examined by experiments with animals. There was no significant difference in bursting pressure of the anastomosis and hydroxyproline content between the two methods. In the histopathological findings, adhesion of the subserosal layer was found at 14 postoperative days and regenerative mucosa at 28 days after operation. In a clinical study, there was no significant difference in frequency of leakage. The value of pancreatic functional diagnostant (PFD) was maintained at a high rate 12 months after operation. It was considered that anastomotic patency was preserved. It is concluded the duct-insertion method is a safe and useful procedure, especially for patients with normal pancreatic tissue and an undilated pancreatic duct.