Masato Kayahara

An evaluation of radical resection for pancreatic cancer based on the mode of recurrence as determined by autopsy and diagnostic imaging.

Background. To determine the extent of dissection in curative resection for cancer of the pancreatic head, the mode of recurrence was determined at autopsy and by radiographic examinations.

Results of extensive surgery for pancreatic carcinoma

Since 1973, 210 patients with pancreatic carcinoma have undergone surgery in our clinic, including 144 with carcinoma of the head of the pancreas. Of these 144 patients, macroscopic curative resections were performed on 53 (36.8%). Five patients (9.4%) died within 30 postoperative days, and an additional 3 (5.7%) died within 60 days. The overall median survival was 13 months. Eight of the patients who underwent macroscopic curative resection survived 5 years, giving a 5‐year survival rate of 27.4% using the Kaplan–Meier method. The 5‐year survival rate was 39.7% after a microscopically curative resection and 0% after a microscopically noncurative resection.

Guidelines for the management of biliary tract and ampullary carcinomas: surgical treatment

The only curative treatment in biliary tract cancer is surgical treatment. Therefore, the suitability of curative resection should be investigated in the first place. In the presence of metastasis to the liver, lung, peritoneum, or distant lymph nodes, curative resection is not suitable. No definite consensus has been reached on local extension factors and curability. Measures of hepatic functional reserve in the jaundiced liver include future liver remnant volume and the indocyanine green (ICG) clearance test. Preoperative portal vein embolization may be considered in patients in whom right hepatectomy or more, or hepatectomy with a resection rate exceeding 50%–60% is planned. Postoperative complications and surgery-related mortality may be reduced with the use of portal vein embolization. Although hepatectomy and/or pancreaticoduodenectomy are preferable for the curative resection of bile duct cancer, extrahepatic bile duct resection alone is also considered in patients for whom it is judged that curative resection would be achieved after a strict diagnosis of its local extension. Also, combined caudate lobe resection is recommended for hilar cholangiocarcinoma. Because the prognosis of patients treated with combined portal vein resection is significantly better than that of unresected patients, combined portal vein resection may be carried out. Prognostic factors after resection for bile duct cancer include positive surgical margins, especially in the ductal stump; lymph node metastasis; perineural invasion; and combined vascular resection due to portal vein and/or hepatic artery invasion. For patients with suspected gallbladder cancer, laparoscopic cholecystectomy is not recommended, and open cholecystectomy should be performed as a rule. When gallbladder cancer invading the subserosal layer or deeper has been detected after simple cholecystectomy, additional resection should be considered. Prognostic factors after resection for gallbladder cancer include the depth of mural invasion; lymph node metastasis; extramural extension, especially into the hepatoduodenal ligament; perineural invasion; and the degree of curability. Pancreaticoduodenectomy is indicated for ampullary carcinoma, and limited operation is also indicated for carcinoma in adenoma. The prognostic factors after resection for ampullary carcinoma include lymph node metastasis, pancreatic invasion, and perineural invasion.

Surgical strategy for carcinoma of the pancreas head area based on clinicopathologic analysis of nodal involvement and plexus invasion.

BACKGROUND The pattern of tumor spread, vis-à-vis nodal involvement and invasion of the extrapancreatic plexus (Plx), has not been thoroughly described for carcinoma of the pancreatic head area. METHODS From 1973 to 1991, 110 patients (49 with carcinoma of the pancreatic head [Ph], 29 with distal bile duct cancer [Bi], and 32 with carcinoma of the papilla of Vater [Pv]) underwent pancreatectomy at Kanazawa University Hospital. Nodal involvement and Plx invasion were precisely evaluated by histopathologic examination. RESULTS Thirty-seven (76%) of the 49 patients with Ph, 20 (69%) of the 29 with Bi, and 14 (44%) of the 32 with Pv had nodal involvement. The lymph nodes most commonly involved for Ph were the posterior pancreaticoduodenal lymph nodes (numbers 13a [superior] and 13b [inferior]), the superior mesenteric lymph nodes (number 14), the paraaortic lymph nodes (number 16), and the anterior pancreaticoduodenal lymph nodes (number 17) (13a, 51%; 13b, 47%; 14, 36.7%; 16, 18.4%; 17a, 33%; 17b, 22%). In patients with Bi, lymph nodes around the hepatoduodenal ligament (number 12) and lymph nodes numbers 13a and 14 were most commonly involved (12, 27.6%; 13a, 51.7%; 14, 34.5%). In patients with Pv, lymph node numbers 13b and 14 were most frequently involved (13b, 34.4%; 14, 15.6%). No significant correlation was noted between the tumor size and nodal involvement in these three lesions. Nodal involvement was an important prognostic factor for carcinoma of the pancreatic head area. Plx invasion in these three carcinomas was observed in 61% of patients with Ph, 29% of patients with Bi, and 3% of patients with Pv. CONCLUSIONS Nodal involvement and Plx invasion differed significantly among carcinomas of the pancreatic head area. We believe that nodal dissection of at least group number 14 is needed for Ph, Bi, and Pv cancers. In addition, dissection of lymph nodes of number 16 and the Plx around the superior mesenteric artery and celiac axis are needed in Ph cancer. Plx dissection of the first portion of plexus pancreaticus capitalis is needed in Bi cancer.

Role of nodal involvement and the periductal soft-tissue margin in middle and distal bile duct cancer.

OBJECTIVE To determine the pattern of middle (Bm) and distal (Bi) bile duct cancers in an attempt to optimize surgical treatment. SUMMARY BACKGROUND DATA Lymph node involvement and neural plexus invasion are the prognostic factors most amenable to surgery in Bm and Bi disease. However, a detailed analysis of these factors has not been conducted. METHODS Fifty patients with Bm and Bi disease (Bm 14 patients, Bi 36 patients) were examined histopathologically. A precise determination was made of lymph node involvement and neural plexus invasion. Important prognostic factors were examined by clinicopathologic study to apply these findings to surgical management. RESULTS Frequencies of nodal involvement for Bm and Bi disease were 57% and 71%, respectively. The inferior periductal and superior pancreaticoduodenal lymph nodes were most commonly involved. Neural plexus invasion occurred in 20% of patients, particularly involving the plexus in the hepatoduodenal ligament and pancreatic head. Tumor was present at the surgical margin in 50% and 14% of patients with Bm and Bi disease, respectively. Five-year survival rates were 65% in the absence of nodal metastasis and 21% with nodal metastasis. A significant correlation existed between absence of tumor at the surgical margin and survival. A Cox proportional hazard model projected absence of tumor at the surgical margin, followed by nodal involvement, as the strongest prognostic variables. CONCLUSIONS Absence of tumor at the surgical margin and nodal involvement are important independent prognostic factors in Bm and Bi disease. Skeletonization of the hepatoduodenal ligament, including portal vein resection, is necessary for patients with Bm disease, and a wide nodal dissection is essential in all patients.

Clinical study of lymphatic flow to the paraaortic lymph nodes in carcinoma of the head of the pancreas

Background. At Kanazawa University, the authors have been developing an appropriate radical operation for the treatment of cancer of the head of the pancreas. As a result of previous research, it was believed that lymphatic metastasis of carcinoma of the head of the pancreas should be investigated more thoroughly to improve the surgical results.

A clinicopathologic study on neural invasion in cancer of the pancreatic head

Thirty‐four patients who had resection of cancer of the pancreatic head were examined clinicopathologically to elucidate neural invasion of cancer of the pancreatic head to the extrapancreatic nerve plexus. Invasion of cancer to the retropancreatic tissue (rp+) was observed in 29 (85%) of the 34 patients, and neural invasion to the extrapancreatic nerve plexus was observed in 21 (72%) of the 29 patients with rp+. The incidence of invasion to the second region of the nerve plexus of the pancreatic head was high (14 patients; 67%). The degree of the neural invasion tended to increase as the intrapancreatic neural invasion became more severe and lymph vessel invasion more marked. Based on these findings, en bloc resection of the retropancreatic tissue involving the nerve plexus and fat tissue is necessary in the surgical treatment of cancer of the pancreatic head. Cancer 1992; 69:930–935.

Lymphatic flow in carcinoma of the head of the pancreas.

The lymphatic pathway from the head of the pancreas to the para‐aortic lymph nodes was examined on the basis of the frequency of lymph node involvements. Forty‐four patients were examined. All patients had extended radical operations. Thirty‐one of 44 (70.5%) patients had lymph node involvement. The lymph nodes that had a high metastatic rate included the following: (1) lymph nodes around the common hepatic artery (number 8 lymph node); (2) lymph nodes of the hepatoduodenal ligament (number 12 lymph node); (3) the posterior pancreaticoduodenal lymph node (number 13 lymph node); (4) lymph nodes around the superior mesenteric artery (number 14 lymph node); (5) para‐aortic lymph nodes (number 16 lymph node); and (6) the anterior pancreaticoduodenal lymph node (number 17 lymph node). Twenty‐eight of these 31 patients had disease in the posterior pancreaticoduodenal lymph node. The patterns of lymph node involvement consisted of four combinations: number 13‐number 17, number 13‐number 14, number 14‐number 16, and number 17‐number a. All of the patients with number 16 nodal involvement had number 14 lymph node metastasis. However, there was no relationship between tumor size and lymph node involvement.

Recent trends of gallbladder cancer in Japan : An analysis of 4770 patients

Gallbladder cancer is the most common cancer of the biliary tract and has a particularly high incidence in Chile, Japan, and northern India. Many Japanese surgeons have reported that aggressive surgery improves the outcome of patients with gallbladder cancer. Differences in survival rates between Japan and other countries have been noted. The objective of this study was to determine whether there were any changes over time in the incidence, therapeutic approach, stage at diagnosis, or prognosis of gallbladder cancer in an unselected, community‐based series of patients in Japan.

The nature of neural invasion by pancreatic cancer.

Objectives: Neural invasion is one of the most important modes of tumor extension in pancreatobiliary tract cancer. However, the precise pattern of neural invasion and the relationship between neural invasion and nodal involvement are unknown. Methods: Using 8 surgical specimens from patients with pancreatic cancer, 4973 sections were created and examined histopathologically. A total of 961 sections of VX2 tumor grown in the retroperitoneum of rabbits also were examined histologically. The precise mechanism by which neural invasion occurs and the relationship between nerve fascicle and lymph node involvement were determined by histological examination of serial sections. Results: Histological evaluation of the surgical specimens revealed continuity between the cancer cells between the inside and the outside of the perineurium. Tumor cells grew mainly in a continuous fashion along the branches of nerves. An advancing tip of the tumor cells was identified. The pattern of tumor spread in the experimental study was similar to that in the clinical study. Continuity was found between the cancer cells inside some lymph nodes and the cancer cells within the perineural space. This finding suggests that neural invasion might be a pathway to lymphatic involvement. Conclusions: Neural invasion is a common, but not a specific, feature of pancreatic cancer. Tumor cells in the perineural space grow in a continuous fashion and may be responsible for some cases of lymphatic spread.