Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

OBJECTIVES

Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality.

DESIGN

Retrospective multinational study including SCN diagnosed between 1990 and 2014.

RESULTS

2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1).

CONCLUSIONS

After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN.

TRIAL REGISTRATION NUMBER

IRB 00006477.

Effects of adjuvant intra-operative radiation therapy after curative resection in pancreatic cancer patients : Results of a randomized study by 11 institutions in Japan

4622

Background: To evaluate the benefits of adjuvant intra-operative radiation therapy after curative resection in advanced pancreatic cancer (APC) patients, a multi-center phase III trial was conducted by 11 participating institutions in Japan. Methods: Eligibility included pts with potentially resectable APC (duct cell origin) by image diagnosis. Patients were randomized in a 1:1 ratio to adjuvant IORT or surgery alone less than a week before surgery. Stratification factors were tumor size (TS1/TS2,3,4), location (head/body and tail), and institution. Patients who were assigned to adjuvant IORT arm received IORT after curative resection before reconstruction. IORT consisted of 25Gy with electron beam energies of more than 6MeV and was delivered by the round shaped acrylic cylinder of 6–8cm diameter. The radiation field included the tumor bed and in most cases included the celiac axis, superior mesenteric artery, and the portal vein. The primary endpoint was overall survival. The secondary endpoint was local control rate at 2 years after surgery. Assuming 65 eligible pts in each arm, the study had 0,8 power to detect 20% difference in 2-year survival rate. Results: Between 05/2002 to 12/2006 198 pts were randomized and 153 pts underwent curative resection with assigned treatment. Among the 153 pts with curative resection, seven pts revealed ineligible by the histological examination. Finally full analysis sets were 144 pts. Seventy three pts were in the IORT arm and 71 pts in the surgery alone arm. There was only one hospital death in the IORT arm. Cause of the death was intraabdominal arterial bleeding due to pancreatic fistula. Conclusions: We now are collecting the final follow up data. The final analyses will be presented at the meeting.

No significant financial relationships to disclose.

In vivo effect of pancreatic phospholipase A2 on the arachidonic acid cascade

BACKGROUND

In acute pancreatitis, pancreatic phospholipase A2 increases in systemic circulation. Yet the pathophysiological significance is controversial, because previous in vitro studies have shown that the enzyme has little cytotoxicity or ability to activate the arachidonic acid cascade by itself in contrast to other isozymes.

AIM OF THE STUDY

The aims of this study are to examine the effect of pancreatic phospholipase A2 on the arachidonic acid cascade in vivo; to explain the discrepancy, if present, between in vitro and in vivo findings; and to reassess the pathophysiological significance of circulating pancreatic phospholipase A2.

METHODS

Pancreatic phospholipase A2 was infused intravenously in guinea pigs, and changes in the arachidonic acid cascade, plasma lipoprotein, and cardiopulmonary function were investigated.

RESULTS

Plasma concentrations of 6-keto-prostaglandin F1alpha, prostaglandin E2, and thromboxane B2 increased after intravenous (iv) infusion of pancreatic phospholipase A2. Some of the plasma phospholipids such as phosphatidylcholine and phosphatidylethanolamine decreased, and free dihomo-gamma-linolenic acid, arachidonic acid, and eicosapentaenoic acid were detected in plasma. These changes were accompanied with decreases in blood pressure, heart rate, and base excess.

CONCLUSION

Circulating pancreatic phospholipase A2 activates the arachidonic acid cascade, probably by supplying free eicosanoid precursors from plasma lipoprotein to eicosanoid-producing cells. It is supposed to be a cause of systemic complications in acute pancreatitis.

Origin of the thoracic duct and pancreaticoduodenal lymphatic pathways to the para-aortic lymph nodes

We investigated the afferent and efferent connections of the para-aortic lymph nodes (group 16 nodes) relative to the origin of the thoracic duct in 85 postmortem cadavers. The origin was usually restricted to groups 16b1-inter and -latero nodes (type I; 90.6%), regardless of whether the union of their efferents occurred at the abdominal or thoracic level. We also occasionally observed thick collecting vessels originating from the dorsal aspect of the pancreaticoduodenal region, running along the right side of and superficial to the celiac plexus and emptying into group 16b1 nodes. The thoracic duct originated occasionally not only from group 16b1 nodes but also from group 16a2 nodes (type II; 9.4%). Moreover, in all 85 specimens, the group 16a2-inter node often received afferents from the celiac plexus itself or the tight connective tissue between the plexus and diaphragmatic crus, or both. The results support the reliability of the extended D2 lymphadenectomy (D2 + group 16b1 nodes + group 16a2-inter node) for curative cancer surgery in the pancreaticoduodenal region.

Primary sclerosing cholangitis successfully treated by resection of the confluence of the hepatic duct

Primary sclerosing cholangitis (PSC) is a cholestatic disease characterized by chronic inflammatory fibrosis of the extra- and intrahepatic bile ducts. Although the prognosis of patients with PSC was believed to be poor, some patients have not experienced the expected rapid clinical progression. A 51-year-old man with PSC was initially hospitalized for jaundice. Laboratory data showed low levels of the complement components C3, C4, and CH50. Percutaneous transhepatic biliary drainage was performed. Cholangiography revealed complete obstruction of the common bile duct below the confluence of the cystic duct. The confluence of the hepatic duct was resected and it was reconstructed by hepaticojejunostomy for palliation of the obstructive jaundice. Increased thickness of the walls of the common bile duct, right hepatic bile duct, and gallbladder was observed. Histopathological examination of the resected specimen revealed periductal fibrosis, with an onion-skin-like appearance. The patient is currently doing well, approximately 7 years after the surgery, without any signs of PSC recurrence. In this extraordinary patient, the laboratory data for C3, C4, and CH50 showed a complete return to normal levels. The positive results in this patient suggest that resection of the confluence of the hepatic duct may be an effective surgical treatment for noncirrhotic PSC patients who have dominant extrahepatic strictures.

Frequent loss of expression without sequence mutations of the DCC gene in primary gastric cancer

Loss of heterozygosity (LOH) on chromosome 18q21 is frequently found in various human cancers, suggesting the presence of tumour suppressor gene(s) in this chromosomal region. DCC is the most likely target of LOH because loss or reduction of DCC expression has been found in many types of cancers. However, few reports have focused on sequence mutations of this gene. We investigated sequence mutations and expression of DCC in primary gastric cancers. We studied mutations in 25 of the 29 DCC exons by PCR-SSCP in 17 primary gastric cancers exhibiting LOH on 18q21. No mutations of DCC were found in any of the tumours, although 78% (47/60) of the primary tumours showed apparent loss or reduction of DCC expression by immunohistochemistry. Analysis of methylation status of DCC revealed that methylation frequently occurred in both primary tumours (75%; 45/60) and corresponding non-cancerous gastric mucosae (72%; 43/60). Methylated status of DCC was significantly correlated with the loss of DCC expression in primary tumours (P< 0.01). These results indicate that DCC is frequently silenced, probably by epigenetic mechanisms instead of sequence mutations in gastric cancer.

Surgical anatomy of the pancreas for limited resection

The fusion fascia of the head of the pancreas is called the "fusion fascia of Treitz" and that of the body and tail of the pancreas is termed the "fusion fascia of Toldt". The fusion fascia is histologically composed of a loose connective tissue membrane. All of the important pancreaticoduodenal arcades of arteries and veins are situated on this membrane, i.e., between this membrane and the pancreatic parenchyma. The topography of the head of the pancreas shows that, after departing from the gastroducodenal artery, the anterior superior pancreaticoduodenal artery runs toward a point 1.5 cm below the papilla of Vater, then turns to the posterior aspect of the pancreas to join the anterior inferior pancreaticoduodenal artery. For preserving the duodenum, the artery toward the papilla is very important. The artery toward the papilla of Vater runs along the right side of the common bile duct after departing from the posterior superior pancreaticoduodenal artery. The gastrocolic trunk of Henle has been reported to be found in about 60% of individuals. It is possible that the gastroepiploic vein and anterior superior pancreaticoduodenal vein (ASPDV) can be divided at pancreaticoduodenectomy, with preservation of the superior right colic vein, if this area is free of carcinoma. The ASPDV and anterior inferior pancreaticoduodenal vein form an arcade on the anterior surface of the pancreas. However, arcade formation was not found between the posterior superior pancreaticoduodenal vein and posterior inferior pancreaticoduodenal vein in many of the individuals examined. The vein joined by the inferior mesenteric vein was also investigated.

Molecular characterization of undifferentiated-type gastric carcinoma

As the great majority of gastric cancers develop histologically differentiated, and a significant proportion of differentiated-type carcinomas progress to become undifferentiated, both histological types are likely to share several common genetic abnormalities, such as p53 mutations at advanced stages. However, a subset of gastric cancers develop as undifferentiated carcinomas, including signet-ring cell carcinoma and poorly differentiated adenocarcinoma, and the molecular pathogenesis of this tumor type remains largely unknown. To characterize the molecular features of undifferentiated-type gastric carcinomas that developed as undifferentiated-type, we examined for p53, APC, and epithelial (E)-cadherin gene mutations, microsatellite alterations including loss of heterozygosity (LOH) and microsatellite instability (MSI), and hypermethylation of the E-cadherin gene promoter in 26 early undifferentiated gastric carcinomas, consisting of 14 signet-ring cell carcinomas and 12 poorly differentiated adenocarcinomas. E-cadherin expression was evaluated immunohistochemically. p53 mutations were detected in only one poorly differentiated adenocarcinoma sample (3.8%; 1/26), whereas no APC or E-cadherin mutations were found. LOH was present only at D8S261 on the short arm of chromosome 8 in 2 of 14 (14%) informative tumors, both of which were poorly differentiated adenocarcinomas, and MSI was not observed in any of the tumors. No signet-ring cell carcinomas have been found to carry gene mutations or microsatellite alterations. In contrast, hypermethylation of the E-cadherin promoter occurred in 69% (18/26) of the tumors; 57% (8/14) of signet-ring cell carcinomas, and 83% (10/12) of poorly differentiated adenocarcinomas, and was significantly associated with loss or reduced expression of E-cadherin. Thus, whereas tumor suppressor gene mutation, LOH, and MSI were less common in undifferentiated-type early gastric carcinomas, epigenetic inactivation of E-cadherin via promoter hypermethylation may be an early critical event in the development of undifferentiated tumors.

Successful resection of a liver metastasis from gastric leiomyoblastoma: report of a case

A 20-year-old woman was referred to our hospital for detailed investigation of a gastric submucosal tumor. A leiomyoma was preoperatively diagnosed and laparoscopic-assisted enucleation was performed. The resected tumor was 4 x 3 x 1.5 cm in size and postoperative histological examination identified it as a gastric leiomyoblastoma. Therefore, a secondary resection in the form of a distal gastrectomy was carried out. No tumor cells were found in the gastric specimen or in the lymph nodes; however, 5 months after the operation, an abdominal computed tomography scan revealed a recurrence in the liver, and she was readmitted for further examinations. The lesion was diagnosed as a single liver metastasis from the gastric leiomyoblastoma and successfully resected. The histopathological findings of the liver tumor resembled those of the primary gastric tumor. Her postoperative course was uneventful and she has been well, without any evidence of recurrence, to date. Only 12 other cases of leiomyoblastoma of the stomach with liver metastasis have been reported in Japan, all of which were associated with a very poor prognosis. Therefore, patients with this unusual disease entity should be carefully followed up after resection of the primary tumor.

Long descending lymphatic pathway from the pancreaticoduodenal region to the para-aortic nodes: its laterality and topographical relationship with the celiac plexus

In 6 of 15 postmortem-treated cadaveric specimens, we found macroscopically thick lymphatic collecting vessels that originated from not only the nodes along the common hepatic artery (No. 8 nodes) but also from the pancreaticoduodenal region, and which drained directly into the para-aortic nodes immediately below the left renal vein (No. 16b1-inter or -latero nodes). The collecting vessels, if they originated from the ventral (dorsal) visceral side, passed to the left (right) of the superior mesenteric and celiac arteries. Moreover, the right-side vessels (5 specimens) were classified into superficial and deep courses to the celiac plexus, whereas they were superficial in the left side (2 specimens). One of the deep (right) courses continued to the thoracic duct without any intercalated nodes. In addition, another deep route drained into the para-aortic node immediately above the left renal vein (No. 16a2-inter node). We consider that these collecting vessels form "direct descending pathways" from the relatively peripheral lymphatics in the upper abdomen toward the thoracic duct origin. The pathway seems to be a collateral, or even major drainage route, and it appears responsible for skipped metastasis of primary cancer. Since the classical, limited entity of the intestinal lymph trunk does not coincide with our pathway, it should be reconsidered. The proposed entity of the direct, long descending pathway will influence the selection and modification of lymphadenectomy methods in cancer surgery in the pancreaticoduodenal region.

Drainage for acute pancreatitis

In severe acute pancreatitis, the drainage of activated pancreatic enzymes, infectious substances and necrotic tissue from the abdominal cavity is critical, especially after the operation. We use Faycon drainage tubes together with multi-use feeding tubes. Just after the operation, normal saline is added through the feeding tube and the Faycon drainage tube is suctioned continuously. Irrigation is necessary for more than two weeks.

A case report of cribriform carcinoma of the pancreas with long time survival

A 62-year-old man had complained of left abdominal pain and tenderness and a body weight loss. Abdominal ultrasonography and computed tomography revealed homogeneous tumor with clear margin, and an irregular shape (3.5 x 2.0 cm) in the body of the pancreas. Endoscopic retrograde cholangiopancreatography showed a shadow defect in the main pancreatic duct adjacent to the tumor, which suggested intraductal tumor spread. Distal pancreatectomy with splenectomy and left paraaortic lymph node dissection was performed. Microscopically, the tumor showed microtubular carcinoma, which was characterized by a cribriform pattern, medullary growth, and little interstitium. The tumor was encapsulated by a relatively thick fibrous capsule. The patient was discharged uneventfully, and he is alive 33 months after operation without a distinct sign of recurrence. In conclusion, cribriform carcinoma of the pancreas has specific characteristics, such as good prognosis, expansive growth with little invasion, intraductal growth and spread without mucin production and histological marked cribriform pattern. This type of carcinoma should be classified as a new disease entity of carcinoma of the pancreas.

[Diseases of the biliary tract and pancreas in the aged--results obtained by investigation of the autopsy cases]

Gross and histological examination of the autopsy cases in the aged revealed that: 1. Acute interstitial pancreatitis, which was characterized by rupture of the ducts and ductules associated with profuse intraluminal exudation of polymorphonuclear leucocytes and protein plugs formation, was found in nine cases (0.62%) out of 1457 autopsies. There was scarce parenchymal or fat necrosis which might be caused by impaired secretion by atrophic parenchyma. The interstitial type may represent characteristics of acute pancreatitis in the aged. 2. Pancreatic lithiasis was found in six of 85 cases, or 7.1%. 3. Sites of isolated islets of Langerhans were found in an incidence of 26.5% (53/200), which increased with age. 4. Incidence of endocrine tumors was 10% (6/60) in individuals having histological studies of all sections and 1.6% (12/738) in individuals having histological studies of three random sections of the pancreas. The facts that multiple hormone production was found in as much as 70% and glucagon cells in as much as 85% were characteristics. 5. The atypical epithelia were observed with the highest incidence in the common pancreaticobiliary channel of the papilla of Vater, where carcinoma may arise most frequently. 6. The incidence of cystic lesions increased with age. Small cystic lesions appear to have the potential to progress to malignancy. 7. it may be possible to remove the head of the pancreas while preserving of the vascular arcades and their branches to the duodenum, the bile duct and the papilla of Vater. The artery toward the papilla of Vater is very important for the blood supply of both the papilla and second portion of the duodenum, and should be preserved in duodenum-preserving subtotal resection of the head of the pancreas. Gallbladder carcinoma was found in 94 cases, or 2.1% and gallbladder stone was found in 957 cases, or 21.4% among 4482 cases. Incidence of gallbladder carcinoma was six times higher in the cases with cholecystolithiasis than those without stone.

Significance of K-ras mutation and CEA level in pancreatic juice in the diagnosis of pancreatic cancer

The early diagnosis of pancreatic carcinoma is essential for increasing patient survival rates. In this study, 52 patients with suspected pancreatic diseases were examined to investigate the value of K-ras codon 12 point mutation, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9), and cytology of pancreatic juice in the diagnosis of pancreatic carcinoma. Pancreatic juice was taken without secretin stimulation. K-ras mutation was detected by enriched polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). K-ras mutation in pancreatic juice was more frequent in carcinoma than in benign diseases (P = 0.0448). The positive predictive value of K-ras mutation for the diagnosis of neoplastic disease was 83%. The CEA level in pancreatic juice in carcinoma was significantly greater than that in benign disease (P< 0.0001). When the cutoff level of CEA was set at 50 ng/ml, its accuracy for the diagnosis of carcinoma was 85%. A multivariate analysis showed that K-ras mutation and CEA level in pancreatic juice, as well as serum CA19-9 level and age of the patient were independent variables for the diagnosis of carcinoma, and the accuracy of diagnosis by this analysis was increased to 90%. In conclusion, both K-ras mutation and CEA level in pancreatic juice may be valuable for the diagnosis of carcinoma. Better discrimination was possible with a multivariate analysis.

Distinct methylation patterns of two APC gene promoters in normal and cancerous gastric epithelia

The adenomatous polyposis coli (APC) tumor suppressor gene is mutationally inactivated in both familial and sporadic forms of colorectal cancers. In addition, hypermethylation of CpG islands in the upstream portion of APC, a potential alternative mechanism of tumor suppressor gene inactivation, has been described in colorectal cancer. Because a subset of both gastric and colorectal cancers display the CpG island methylator phenotype, we hypothesized that epigenetic inactivation of APC was likely to occur in at least some gastric cancers. APC exhibits two forms of transcripts from exons 1A and 1B in the stomach. Therefore, we investigated CpG island methylation in the sequences upstream of exons 1A and 1B, i.e., promoters 1A and 1B, respectively. We evaluated DNAs from 10 gastric cancer cell lines, 40 primary gastric cancers, and 40 matching non-cancerous gastric mucosae. Methylated alleles of promoter 1A were present in 10 (100%) of 10 gastric cancer cell lines, 33 (82.5%) of 40 primary gastric cancers, and 39 (97.5%) of 40 noncancerous gastric mucosae. In contrast, promoter 1B was unmethylated in all of these same samples. APC transcripts from exon 1A were not expressed in nine of the 10 methylated gastric cancer cell lines, whereas APC transcripts were expressed from exon 1B. Thus, expression from a given promoter correlated well with its methylation status. We conclude that in contrast to the colon, methylation of promoter 1A is a normal event in the stomach; moreover, promoter 1B is protected from methylation in the stomach and thus probably does not participate in this form of epigenetic APC inactivation.

Significance of thymidine phosphorylase/platelet-derived endothelial cell growth factor in carcinoma of the papilla of Vater

The expression of thymidine phosphorylase (TP) in carcinoma of the papilla of Vater was studied to clarify its significance in tumor progression and in determining prognosis. Fifty-nine cases of surgically resected carcinoma of the papilla of Vater were studied. Immunohistochemical staining was performed to evaluate the expression of TP, microvessel count and p53 overexpression. TP expression was demonstrated in tumor cells in 62.7% (37/59) of the cases. A higher frequency of regional lymph node metastasis was found in TP-positive tumors than in TP-negative tumors (P = 0.006). TP-positive tumors were more advanced than TP-negative tumors with regard to clinical stage (P = 0.035). TP-positive tumors had significantly higher microvessel density (27.6 +/- 10.1) than TP-negative tumors (20.4 +/- 10.0, P = 0.01). Moreover, TP expression was significantly correlated with a poor prognosis (P = 0. 02). These suggest that in carcinoma of the papilla of Vater, TP production by tumor cells is correlated with tumor progression through its regulatory effect on neovascularization.

A case of pancreatic carcinoma with marked ductal dilatation: what contributed to the dilatation?

BACKGROUND

We report the case of an 82-yr-old man with invasive ductal carcinoma of the pancreatic head, in which the main pancreatic duct and duct of Santorini were markedly dilated, measuring 1.6 and 1.1 cm, respectively, in diameter on computed tomography.

METHODS

A preoperative diagnosis of ductal carcinoma of the pancreatic head was made, and Whipple's procedure was carried out.

RESULTS

Histopathologically, the tumor was diagnosed as moderately differentiated tubular adenocarcinoma, and the resected pancreatic parenchyma showed low papillary mucous cell hyperplasia and atypical hyperplasia in dilated ductular branches. Conclusion. Even among patients with tubular adenocarcinoma, the most common type of pancreatic ductal carcinoma, if the patient is aged and has chronic pancreatitis, the main pancreatic duct and duct of Santorini may dilate to the same degree as in mucin-hypersecreting neoplasm.

Appraisal of two-staged pancreatoduodenectomy: its technical aspects and outcome

BACKGROUND/AIMS

Leakage from the pancreaticoenteric anastomosis after pancreatoduodenectomy is closely associated with intraabdominal hemorrhage, thus contributing to mortality. Recently, two-staged pancreatoduodenectomy including exteriorization of the pancreatic juice and second-look pancreaticojejunostomy was performed in high-risk patients.

METHODOLOGY

The authors reviewed 24 patients who underwent two-staged pancreatoduodenectomy from November 1994 to April 1999.

RESULTS

Oral intake could be instituted on the 6th (mean) postoperative day. In 23 of the 24 patients, the pancreatic juice leakage stopped within a mean of 10 days without any complications. In the remaining 1, the leakage lasted over 4 weeks and intraabdominal bleeding from the gastroduodenal artery occurred. The median interval between pancreatoduodenectomy and the second operation was 124 days (range: 93-323 days). In 15 patients, a stent tube was placed at the site of pancreaticojejunostomy: 1 patient developed acute pancreatitis due to dislocation of the stent tube, in 3, pancreatic juice leakage necessitated exteriorization of the juice, and the remaining 11 recovered uneventfully. In the other 9 patients, the pancreatic juice was exteriorized: 1 patient had leakage and the other 8 recovered uneventfully. Overall, there was no mortality.

CONCLUSIONS

Our two-staged pancreatoduodenectomy is considered to make pancreatoduodenectomy performable safely without any mortality. This procedure is recommended for selected patients, including those who require concomitant major hepatectomy or resection of other organs or who have liver cirrhosis, and may be indicated for patients who have a soft and fragile pancreas or pancreatic trauma.

Comparison of diclofenac and fluorometholone in preventing cystoid macular edema after small incision cataract surgery: a multicentered prospective trial

PURPOSE

To compare a nonsteroidal topical solution (0.1% diclofenac) to a steroidal topical solution (0.1% fluorometholone) in preventing cystoid macular edema (CME) and disruption of the blood-aqueous barrier.

METHODS

A multicentered, prospective clinical trial was performed on eyes undergoing phacoemulsification followed by implantation of a foldable acrylic intraocular lens by the envelope technique. The presence and degree of cystoid macula edema (CME) was determined by fluorescein angiography. A breakdown of the blood-aqueous barrier was determined by laser flare-cell photometry.

RESULTS

Five weeks after surgery, CME was present in 3 of 53 eyes (5.7%) receiving diclofenac and in 29 of 53 eyes (54.7%) receiving fluorometholone. This difference was statistically significant (P < .001). The amount of flare in the anterior chamber at 3 days, 1, 2, 5, and 8 weeks after surgery was also significantly lower (P < .01-P < .001) in the diclofenac group. The degree of flare at 3 days, 1, 2, 5, and 8 weeks after surgery was significantly higher in eyes with CME (P < .001).

CONCLUSIONS

These findings suggest that diclofenac effectively prevents CME following cataract surgery and that CME is closely related to the breakdown of the blood-aqueous barrier.

Giant solid cystic tumor of the pancreas with a fibrous septum caused by extracapsular growth in middle-aged woman: report of a case

We report herein the case of a 57-year-old female who was admitted to our hospital for treatment of rectal carcinoma and incidentally found to have a giant cystic tumor, 20 cm in diameter, in the body and tail of the pancreas. Several imaging procedures, including ultrasonography, computed tomography, and magnetic resonance imaging, showed that this tumor was round and hypovascular, and had a septum with protuberant lesions. The capsule was 3-4 mm thick with partial calcification. A preoperative diagnosis of a solid cystic tumor (SCT) of the pancreas was made, even though these tumors are rarely found in females in their fifties. Moreover, few reports of SCT with a septum have been described. Distal pancreatectomy and splenectomy were performed, and the tumor was found to be filled with massive necrotic tissue. Microscopically, the tumor was confirmed to be a SCT with a fibrous septum. We present this case due to the atypical findings, including the age of the patient and the existence of a septum caused by extracapsular growth.

Management of severe acute pancreatitis with a somatostatin analog in a patient undergoing surgery for dissecting thoracic aneurysm: report of a case

A patient who was admitted to our hospital to undergo surgery for a dissecting thoracic aneurysm suffered preoperatively from severe acute pancreatitis with pancreatic pseudocysts. Computerized tomography (CT) demonstrated the presence of new fluid collection around the cyst with the absence of pancreatic necrosis. He was given a somatostatin analog (sandostatin), which was effective in decreasing the abdominal symptoms, leukocyte counts, and the serum C-reactive/protein level. A CT scan revealed that the pancreatic pseudocyst and peripancreatic fluid collection had disappeared. Although somatostatin has been reported to be ineffective for acute pancreatitis with necrosis, pancreatitis without necrosis may regress after treatment with sandostatin. This is probably due to its suppressive effect on the exocrine function, thus resulting in a decrease of pancreatic juice infiltration.

p53 and p21/Waf1 protein expression and K-ras codon 12 mutation in carcinoma of the papilla of Vater

OBJECTIVE

There have been few studies on the molecular biological characteristics of carcinoma of the papilla of Vater. In this study, p53 and p21/Waf1 expression and K-ras codon 12 mutation in carcinoma of the papilla of Vater were investigated.

METHODS

Thirty-seven cases of carcinoma of the papilla of Vater were studied. Macroscopically, the carcinoma was ulcerative in 15 cases and nonulcerative in 22 cases. Histologically, nine were intestinal type, 27 were pancreaticobiliary type, and one was undifferentiated. Formalin-fixed, paraffin-embedded sections were immunohistochemically stained for p53 and p21. K-ras codon 12 mutation was detected with the two-step polymerase chain reaction-restriction fragment length polymorphism method, followed by direct sequencing.

RESULTS

p53 overexpression was found in 17 of 37 cases (46%) and was more frequent in the ulcerative type than in the nonulcerative type (67% vs 32%, p < 0.05). p21/Waf1 protein expression was found in 15 of 37 cases (41%), and was not correlated with that of p53. K-ras codon 12 mutation was found in 14 of 37 cases (38%), and was more frequently detected in the intestinal type than in the pancreaticobiliary type (66% vs 30%, p < 0.05). On direct sequencing, the mutations were mainly GGT to GAT (9/14) and GGT to GTT (4/14). The type of mutation did not correlate with the histological type.

CONCLUSIONS

In carcinoma of the papilla of Vater, p53 overexpression may play a role in tumor ulceration. p21/Waf1 expression is induced via a p53-independent pathway. Carcinomas of the intestinal and pancreaticobiliary types may develop via different mechanisms, and K-ras mutation is mainly associated with the intestinal type.

Rescue of liver grafts from hepatic artery occlusion in living-related liver transplantation

BACKGROUND

Hepatic artery thrombosis after liver transplantation remains a significant cause of graft loss and death. Retransplantation is a difficult option after living-related liver transplantation in Japan.

METHODS

Twenty-seven patients underwent living-related liver transplantation with left-sided liver grafts donated from their relatives. The hepatic artery was anastomosed end to end under a surgical microscope. Anticoagulant therapy was maintained for 2 weeks after operation. Routine post-transplant Doppler ultrasonography together with serum blood tests were performed twice a day during the first 2 weeks.

RESULTS

Three patients developed hepatic artery occlusion, which was identified by routine Doppler ultrasonography before the serum transaminase values increased on days 7, 7 and 3 after surgery respectively. In two of the three patients, no apparent arterial thrombosis was recognized and vasospasm was therefore considered to be the cause of the occlusion. Arterial patency was restored by urgent revascularization with reanastomosis in all patients, but one patient with a functional graft died from a cerebral haemorrhage on day 47.

CONCLUSION

Early diagnosis of hepatic artery occlusion by routine Doppler ultrasonography and revascularization of the graft is an indispensable strategy for preventing graft loss after living-related liver transplantation.

Proposal on the extent of lymph node dissection for gallbladder carcinoma

BACKGROUND/AIMS

To evaluate the value of performing extended regional lymph node dissection for gallbladder carcinoma, the mode of recurrence after curative resection was analyzed.

METHODOLOGY

Records of 45 patients who underwent surgical resection for gallbladder carcinoma from 1973 to August 1997 were reviewed.

RESULTS

Thirty-three cases underwent a curative resection and 12 received a non-curative resection. Among the 32 patients who survived the curative resection, cancer recurred in 7 with lymph node metastasis, whereas recurrence was found in only 1 of the remaining 25 patients without lymph node metastasis (p < 0.0001). At the 1st diagnosis of recurrence in these 8 patients, lymph node recurrence was detected in 7, and the site of recurrence was limited to the lymph nodes, which were confined to the peripancreatic region and the interaortocaval nodes near the left renal vein in 4 cases.

CONCLUSIONS

In view of the site of the metastatic lymph nodes and the lymphatic drainage system of the gallbladder, it was considered that lymph node dissection was inadequate in 5 of the 8 patients and that 2 might have been cured by extended regional lymph node dissection, including complete resection of the retroportal, posterior pancreatoduodenal, right celiac and interaortocaval nodes.

A rare combination consisting of primary hyperaldosteronism and glucagonoma

A 59-yr-old man with multiple pancreatic tumors is presented. Previously, he had undergone left adrenalectomy for primary hyperaldosteronism and left nephrectomy for renal cell carcinoma at the ages of 39 and 55 yr, respectively. This time, 3 yr after removal of renal cancer, two solid lesions in the pancreas associated with hyperglucagonemia were detected. Under a diagnosis of pancreatic metastasis from renal cell carcinoma or islet cell tumor of the pancreas, distal pancreatectomy with splenectomy and enucleation of the tumor in the pancreas head were performed. Microscopically, a glucagonoma, measuring 2.3 mm in diameter, was detected among five pancreatic metastases from renal cell carcinoma. Four years after surgery, the patient remains well, without signs of recurrence despite multiple pancreatic metastases. This is the first report of such a rare combination consisting of aldosterone-secreting adrenal adenoma and glucagonoma.

The development of a pancreatic abscess, suppurative pylethrombosis, and multiple hepatic abscesses after a pancreatojejunostomy for chronic pancreatitis: report of a case

We present herein an autopsy case of 63-year-old Japanese man who died as a result of pancreatic abscess, suppurative pylethrombosis, and multiple liver abscesses that had developed 10 years after a pancreato- and cystojejunostomy with side-to-side anastomosis for chronic pancreatitis. Even after this operation, the patient had continued to consume excessive amounts of alcohol. He had first experienced back pain with leukocytosis 9 years after the operation, which relapsed the following year. Despite percutaneous transhepatic gallbladder drainage, his icterus had deteriorated into hepatic insufficiency. Computed tomographic scans of the abdomen had disclosed multiple liver abscesses. At autopsy, a pancreatic abscess and suppurative pylethrombosis as well as multiple liver abscesses were found. There have been few reported cases of such lethal complications developing after a pancreato- and cystojejunostomy for chronic pancreatitis. As the consumption of alcohol would have exacerbated the chronic pancreatitis, such patients should be strongly advised to abstain from drinking alcohol.

Three generations of hereditary chronic pancreatitis

The patient was a 22 year-old male. Hereditary chronic pancreatitis was suspected as a diagnosis since his mother's uncle had been operated on for chronic pancreatitis 14 years previously at the age of 64 years and his mother had been operated on for chronic pancreatitis with calculi 5 years previously at the age of 40 years. Surgery was needed, since: 1) he had experienced abdominal pain for 8 years; 2) endoscopic retrograde cholangiopancreatography (ERCP) revealed a marked irregular dilatation in the main pancreatic duct and a marked irregular dilatation and protein plugs in the ductule of the tail of the pancreas; and, 3) pancreatic functional diagnostic (PFD) test examination showed a 75% decrease in exocrine function. If a surgical procedure had not been performed, the patient would likely have experienced calculi formation in the pancreas and a further decrease in exocrine function. Since the patient was very young and had many protein plugs in the dilated ductule of the tail of the pancreas, we decided to perform a spleen-preserving Puestow's procedure with removal of the tail of the pancreas. Clinical and pathological findings of hereditary pancreatitis are reviewed.

Endoscopic resection of adenoma of the minor papilla

Tumors of the minor papilla of the duodenum are rare. We successfully and safely treated a 16 mm sessile adenoma of the minor papilla using endoscopic resection. Endoscopic retrograde cholangiopancreatography (ERCP) yielded a normal cholangiopancreatogram with blind termination of the duct of Santorini in the minor papilla. We recommend endoscopic resection and histological examination of the entire lesion for adenomas of the minor papilla in patients without pancreas divisum.

Operative indications for cystic lesions of the pancreas with malignant potential--our experience

BACKGROUND/AIMS

There are still many important but unclear points regarding the differential diagnosis and operative indications of cystic lesions of the pancreas with malignant potential. Studies of the clinicopathological and molecular biological characteristics of such diseases are necessary. In this paper, we discuss operative indications for this condition based on a review of the literature and our own experience.

METHODOLOGY

Seven cases of serous cystadenoma and 9 cases of mucinous cystadenoma or cystadenocarcinoma of the pancreas that were operated on or autopsied in our department from 1980 to 1996 were analyzed clinicopathologically. Small cystic lesions incidentally found in 300 autopsied cases were also studied. Finally, mucin-producing tumors described in several reports were reviewed, and the branch type of this tumor was especially investigated.

RESULTS

A marked disappearance of pancreatic acini in the upstream pancreas was found when serous cystadenoma became large. Papillary projection was histologically found in all of the cases. Tumorous invasion to the interstitium was suspected in tumors more than 5 cm in diameter, and malignancy was reported when tumors were larger than 6 cm. As for mucinous cystadenocarcinoma, the patients had a poor prognosis. In 2 of 42 cases with a pseudocyst, small duct cell carcinoma was incidentally found adjacent to the pseudocyst on the duodenal side. With regard to branch-type intraductal papillary neoplasm, 80% of the tumors larger than 4 cm were malignant. Most of the small cystic lesions found in elderly autopsy cases were accompanied by hyperplastic epithelia without evidence of malignancy.

CONCLUSIONS

Based on our experience, an operation should be considered and resection is recommended under the following circumstances: 1) cystic lesions in the body and tail of the pancreas in middle-aged women; 2) typical serous cystadenoma larger than 4 cm; 3) mucinous cystadenoma of any size; 4) branch-type intraductal papillary neoplasm larger than about 3 cm; and, 5) pseudocysts of unknown cause. Small cystic lesions in elderly patients should not necessarily be operated on, but should be followed-up carefully.

Significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas

The significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas is still unclear. The aim of this study was to evaluate the significance of K-ras codon 12 point mutation in pancreatic juice in the diagnosis of carcinoma of the pancreas. All of the 78 reports written from 1988 to 1996 on K-ras point mutation of carcinoma, mucin-producing tumors, and hyperplastic epithelia of the pancreas in both surgical or autopsy specimens and pancreatic juice are reviewed. As results, in surgical or autopsy specimens, K-ras mutation was found in 81% of ordinary duct cell carcinoma and in 53% of mucin-producing tumor of the pancreas; this mutation was also found in hyperplastic epithelia in chronic pancreatitis (7%) and in autopsy cases without pancreatic diseases. In pancreatic juice, K-ras mutation was found in 72% of ordinary pancreatic carcinoma and in 53% of mucin-producing tumor, respectively. In conclusion, most previous reports have indicated that K-ras mutation in pancreatic juice is useful for a diagnosis of pancreatic carcinoma. However, since K-ras gene mutation was also detected in non-tumorous lesions, the diagnosis of pancreatic carcinomas is not necessarily correct if it is based solely on the detection of K-ras mutation in pancreatic juice. Future studies should focus on analyzing the amino acid sequence of K-ras mutation or the combination of this mutation with other parameters such as tumor markers in pancreatic juice, to enhance its specificity and accuracy.

Pancreatic mucin-producing adenocarcinoma associated with a pancreatic stone: report of a case

We present an autopsy case of an 83-year-old Japanese man with a mucin-producing adenocarcinoma accompanied by pancreatolithiasis in the head of the pancreas. He suffered from obstructive jaundice and died of disseminated intravascular coagulation. He did not normally drink alcohol and had no history of chronic pancreatitis. The autopsy findings revealed a mucinous cystic tumor, composed of multiple dilatated branches, in the head of the pancreas. Histological examinations showed papillary adenocarcinoma, which scirrhously infiltrated the distal common bile duct with perineural invasion and lymph node involvement. He was thus diagnosed to have mucin-producing branch-type cancer in the head of the pancreas. The main pancreatic duct was dilated, and the residual pancreatic tissue showed moderate fibrosis and parenchymal atrophy. A stone was observed in a dilated branch of the primary lesion. To the best of our knowledge, there have only been five previously reported cases of mucin-producing tumor associated with pancreatolithiasis. Intraductal calcification is a major characteristic of chronic pancreatitis, but it is clinically important not to misdiagnose cancers associated with pancreatolithiasis such as chronic pancreatitis.

Enteral administration of glutamine in purulent peritonitis

The intestinal hypomotility associated with purulent peritonitis is generally regarded as a contraindication to enteral nutrition. However, enteral nutrition may be feasible in suppurative peritonitis if administered with great caution, i.e., assuring the appropriate amount, delivery speed, and osmolality of the enteral formulation. Glutamine (Gln) increases muscle protein synthesis and decreases muscle protein degradation in sepsis, regardless of the route of administration. Therefore, administering small amounts of supplemental Gln via the enteral route to peritonitis patients may be beneficial. Two purulent peritonitis patients received L-Gln through a jejunostomy tube. The average amount of supplemental Gln was 16 g/d. Systemic inflammatory responses, i.e., high temperature and a high serum C-reactive protein level, persisted throughout the treatment period. Femoral arterial and venous blood samples were drawn simultaneously for determination of amino acid levels before and after 7 d of Gln supplementation. Enterally administered Gln was well-tolerated by both patients. There was an increase in plasma Gln levels after Gln supplementation. Moreover, the release of Gln, alanine, and phenylalanine from the lower extremities was lower after as compared to before Gln supplementation. Enteral administration of Gln may be feasible even in purulent peritonitis.

Characteristics and treatment of mucin-producing tumor of the pancreas

BACKGROUND/AIMS

There has been no thorough clinicopathological analysis of a large number of cases with mucin-producing tumor of the pancreas. The aim of this study was to investigate the clinicopathological features of and therapeutic strategy for this ailment.

METHODOLOGY

Two hundred and fifty-nine cases of mucin-producing tumor of the pancreas were analyzed clinicopathologically.

RESULTS

Mucin-producing tumor of the pancreas was found in 177 males and 82 females (M:F=2.2:1). The mean age was 65.5 years. Jaundice, diabetes mellitus and a past history of pancreatitis were found in 15-19% of the cases. The tumor was most frequently (62%) found in the head of the pancreas. Pathologically, hyperplasia or adenoma was found in 58 cases, and adenocarcinoma in 160 cases. Five-year survival rate by the Kaplan-Meier method was 82.6% in all of the cases, and the post-operative survival curve was much better in cases with this type of carcinoma than in cases with ordinary pancreatic duct cell carcinoma (5-year survival rate: 17.3%). Organ-function preserving procedures, such as duodenum preserving subtotal resection of the head of the pancreas or spleen preserving distal pancreatectomy, might be recommended for this disease without infiltration.

CONCLUSIONS

Mucin-producing tumor has unique clinicopathological characteristics, such as the dilated main pancreatic duct or branches, dilatation of the orifice of the papilla of Vater, or a good prognosis. Organ-function preserving procedures should be recommended in some cases with this ailment.

Long-term follow-up of primary anterior chamber intraocular lens implantation

PURPOSE

To evaluate the long-term outcome in eyes having primary anterior chamber intraocular lens (AC IOL) implantation.

SETTING

Kimura Eye and Internal Medicine Hospital, Hiroshima, Japan.

METHODS

Primary AC IOL implantation was performed in 171 eyes from 1983 to 1988. Two lenses were implanted: the open C-loop Simcoe lens and the 4-point fixation Kelman lens. In 86 eyes that had a mean follow-up of 9 years 7 months, visual acuity, corneal endothelial cell density, pupil shape, and the presence of associated complications were examined.

RESULTS

Although the final visual acuity was 0.5 or better in 60 eyes (69%), corneal endothelial cell density was less than 2000 cells/mm2 in 46 eyes (57%). Postoperative complications included a deformed pupil in 48 eyes (56%) and bullous keratopathy in 12 eyes (14%). In 14 eyes the AC IOL was explanted; 11 of these were the open C-loop Simcoe lens.

CONCLUSION

Although our findings show that the open C-loop AC IOL (Simcoe) is contraindicated, implantation of the 4-point fixation AC IOL may be acceptable in selected cases.

Serous cystadenoma of the pancreas with invasive growth: benign or malignant?

We describe a case of serous cystadenoma, that invaded a lymph node and adipose tissue. Preoperatively, the cystic lesion of the pancreas was diagnosed as a serous cystadenoma and subsequently the patient, a 71-yr-old woman, underwent distal pancreatectomy with splenectomy. Macroscopically, a greyish white, externally lobulated and partly ovoid tumor, measuring 12 x 8.5 x 5 cm, occupied the pancreatic body and tail extensively. In cross-section, multiple nodules were observed, which measured from 0.5 to 3 cm in diameter, were separated by hyalinized fibrous septa and were filled with numerous microcysts. Light microscopic findings were consistent with those for serous cystadenoma. At the splenic hilus, the tumor was found to have invaded the lymph node and adipose tissue. Based on the clinicopathological features of the six reported cases, including the present case (which behaved in a malignant fashion in terms of pathological findings of invasion or metastasis), serous cystadenoma should be regarded as having the potential for malignant growth.

Measuring the anterior capsule opening after cataract surgery to assess capsule shrinkage

PURPOSE

To measure anterior capsule opening (ACO) size after acrylic intraocular lens (IOL) implantation and study the natural course of ACO reduction.

SETTING

Kimura Eye and Internal Medicine Hospital, Hiroshima, Japan.

METHODS

This study comprised 32 patients (38 eyes) having continuous curvilinear capsulorhexis, phacoemulsification, acrylic IOL implantation, and a self-sealing incision performed by 1 surgeon. A retroillumination photograph of the ACO was obtained with the Anterior Eye Segment Analysis System and converted to a computer image. The images were used to measure ACO size postoperatively and calculate the reduction ratio. Follow-up was 6 months.

RESULTS

The postoperative reduction ratio in ACO size was 2.14% at 1 week, 3.83% at 1 month, 4.29% at 3 months, and 5.03% at 6 months. In a few cases, the reduction was progressively severe throughout the follow-up.

CONCLUSIONS

The anterior capsule opening shrank rapidly during the first month after acrylic IOL implantation, followed by a slower progressive reduction in the subsequent 6 months. When severe, progressive shrinkage occurs, an anterior neodymium:YAG laser capsulotomy should be performed within 2 months postoperatively.

Hepatic resection for hepatocellular carcinoma -- Japanese experience

In the past 20 years, thanks to the early detection of hepatocellular carcinomas (HCCs), good perioperative care, the evaluation of functional liver reserve, preoperative portal embolization and the improvement in surgical techniques such as intraoperative ultrasonography, the surgical resection of HCC has become very safe. We have performed 367 hepatectomies on 352 patients since 1990 with a surgical mortality, hospital mortality, blood transfusion rate and 5-year survival rate of 0.27, 0.82, and less than 10 and 47.4%, respectively. Our standard method for selecting surgical procedures and perioperative care resulting in low blood transfusion rates and almost no mortality are described. Since 1990, ethanol injection for HCC ablation has been extensively used in Europe and Japan, but results are poorer than with surgical intervention. Therefore, in patients with small HCCs and good liver function, the first choice treatment should not be ethanol injection, but surgical resection.

[Preventive effects of diclofenac ophthalmic solution on post-cataract-surgical cystoid macular edema]

Using eyes undergoing phacoemulsification followed by implantation of a foldable acrylic intraocular lens (IOL) designed for small-incision cataract surgery, a multi-center study was performed to compare a non-steroidal ophthalmic solution (0.1% diclofenac) to a steroidal ophthalmic solution (0.1% fluorometholone) in preventing cystoid macular edema (CME) and inducing disruption of the blood-aqueous barrier determined by laser flare cellmetry. The incidence of CME, noted in 3 out of 53 eyes (5.7%) receiving diclofenac and in 29 out of 53 eyes (54.7%) receiving fluorometholone, was significantly lower in the diclofenac group. The flare in the anterior chamber was also significantly lower in the diclofenac group; when compared between eyes with and without CME, the amount of flare was significantly higher in the former group. These findings suggest that diclofenac effectively prevents CME following cataract surgery and that CME is closely related to the breakdown of the blood-aqueous barrier.

Histologic and biologic patterns of microscopic pancreatic ductal adenocarcinomas detected incidentally at autopsy

BACKGROUND

The major clinical problems with pancreatic carcinoma are its silent course and late, fatal clinical manifestation. The results of treatments of small pancreatic carcinomas (<2 cm in greatest dimension) have led to the assumption that the detection of these cancers at earlier stages would lead to better survival and possible cure. Currently, there is no information about the histologic and biologic patterns of early stage pancreatic carcinoma, and the available data on incidentally detected tumors are fragmentary. The authors observed two incidental microscopic pancreatic ductal adenocarcinomas in female patients who died of advanced gastric carcinoma (Case 1) and renal carcinoma (Case 2).

METHODS

The pancreatic lesions were examined histologically in serial sections and immunocytochemically for islet cells. Microdissection was performed so that the lesions could be examined for c-Ki-ras mutation.

RESULTS

In Case 1, the pancreatic lesion was composed of cystic and solid components. The cystic component consisted of four small cysts compatible with a mucinous cystic tumor and showed no invasion. The solid component was a well-differentiated adenocarcinoma that occupied a 4 x 2 mm area. In Case 2, the pancreatic lesion contained two small, separate cysts, one of which was surrounded by two apparently separate, invasive adenocarcinomas 2.6 x 0.7 mm and 1.2 x 0.5 mm in greatest dimension. There was invasion of pancreatic islets and perineural spaces in both cases; and in Case 2, there was invasion of peripancreatic fatty tissue. In both cases, the epithelia of the cystic components and tumors showed mutation of the c-Ki-ras oncogene at codon 12, with GGT-to-GAT transition. CONCLUSIONS. Pancreatic carcinoma seems to occur under occult circumstances and maintain a silent course. Even in its early developmental stage, the cancer is invasive, primarily affects islets and nerves, and exhibits mutation of the c-Ki-ras oncogene. These findings call for urgency in the development of preventive modalities.

Histologic and biologic patterns of microscopic pancreatic ductal adenocarcinomas detected incidentally at autopsy

BACKGROUND

The major clinical problems with pancreatic carcinoma are its silent course and late, fatal clinical manifestation. The results of treatments of small pancreatic carcinomas (<2 cm in greatest dimension) have led to the assumption that the detection of these cancers at earlier stages would lead to better survival and possible cure. Currently, there is no information about the histologic and biologic patterns of early stage pancreatic carcinoma, and the available data on incidentally detected tumors are fragmentary. The authors observed two incidental microscopic pancreatic ductal adenocarcinomas in female patients who died of advanced gastric carcinoma (Case 1) and renal carcinoma (Case 2).

METHODS

The pancreatic lesions were examined histologically in serial sections and immunocytochemically for islet cells. Microdissection was performed so that the lesions could be examined for c-Ki-ras mutation.

RESULTS

In Case 1, the pancreatic lesion was composed of cystic and solid components. The cystic component consisted of four small cysts compatible with a mucinous cystic tumor and showed no invasion. The solid component was a well-differentiated adenocarcinoma that occupied a 4 x 2 mm area. In Case 2, the pancreatic lesion contained two small, separate cysts, one of which was surrounded by two apparently separate, invasive adenocarcinomas 2.6 x 0.7 mm and 1.2 x 0.5 mm in greatest dimension. There was invasion of pancreatic islets and perineural spaces in both cases; and in Case 2, there was invasion of peripancreatic fatty tissue. In both cases, the epithelia of the cystic components and tumors showed mutation of the c-Ki-ras oncogene at codon 12, with GGT-to-GAT transition. CONCLUSIONS. Pancreatic carcinoma seems to occur under occult circumstances and maintain a silent course. Even in its early developmental stage, the cancer is invasive, primarily affects islets and nerves, and exhibits mutation of the c-Ki-ras oncogene. These findings call for urgency in the development of preventive modalities.

Problems in the diagnosis and treatment of a so-called mucin-producing tumor of the pancreas

Reports of a so-called "mucin-producing tumor of the pancreas" are increasing worldwide. Although the clinicopathologic features and therapeutic strategies of this tumor have been enthusiastically investigated, there are still many unanswered questions regarding this ailment. In this study, problems in the diagnosis and treatment of mucin-producing tumor were analyzed, based on the 259 reported cases of this tumor. The overall 5-year survival rate for resected cases is 83%, which is much higher than that for ordinary duct cell carcinoma (17.3%). However, the 5-year survival rate for carcinoma cases with infiltration into other organs is 28%, which is much lower than those for carcinoma cases without infiltration (86%) and carcinoma cases with infiltration that remained within the pancreatic parenchyma (74%). These results demonstrate that patients with this tumor have a poor prognosis if the tumor infiltrates other organs. In addition, when the spread of the tumor is >6 cm, the prognosis is significantly worse than when the tumor has a spread of <6 cm. The significance of using the presence of K-ras mutation in the pancreatic juice for diagnosis of this tumor and problems of duodenum-preserving pancreatic head resection are discussed.

Surgical indications for small polypoid lesions of the gallbladder

BACKGROUND

To determine which polyps of the gallbladder should be operated upon, we investigated the size and number of polyps in resected gallbladders, and studied changes in gallbladder polyps using ultrasonography (US).

METHODS

We studied 74 resected gallbladders with small polypoid lesions less than 20 mm in diameter, and 60 patients with gallbladder polyps by US. The polyps in resected gallbladders were classified into four groups histologically, and clinical features, maximum diameter, and number of lesions were compared among the groups. In the followed-up cases with gallbladder polyps, the size and number of polyps were examined by US, and changes during the observation period were studied.

RESULTS

The mean diameter of adenoma was 6.00 +/- 3.39 mm (mean +/- SD) and that of cancer 10.8 +/- 4.16 mm; 97% of cholesterol polyps were less than 10 mm in diameter (3.66 +/- 2.68 mm). Neoplastic polyps tended to be single (adenoma, n = 1.40 +/- 0.89; cancer, n = 1.16 +/- 0.40), whereas half of the cholesterol polyps were multiple (n = 3.09 +/- 3.31). However, when there were fewer than 3 lesions, the incidence of neoplasm was 37% among polyps 5 to 10 mm in diameter. A low incidence (6%) of neoplasm was also observed among polyps less than 5 mm in diameter.

CONCLUSIONS

These data indicate that an aggressive surgical approach for small gallbladder polyps is warranted when there are fewer than 3 polyps, regardless of their size.

Heterogeneity of DNA ploidy pattern in carcinoma of the gallbladder: primary and metastatic sites

There are few detailed reports on the heterogeneity of the nuclear DNA ploidy pattern in carcinoma of the gallbladder. We studied twelve autopsied cases who died of extended gallbladder carcinoma. Multiple samples were taken from the primary site (Pri), from direct invasion of the liver (Hinf), from hematogenous metastasis to the liver (H), from lymphatic metastasis (LN) and from peritoneal dissemination (P). The DNA ploidy pattern was investigated by image cytometry. Heterogeneity of the DNA ploidy pattern in Pri, Hinf, H, LN and P was found in 7/11, 2/10, 5/10, 2/6 and 3/6 cases, respectively. Aneuploidy was more frequently found in Hinf than at the Pri. The DNA index of Hinf was significantly higher than that of Pri. Several stemlines, with different quantities of DNA, were found in Pri. Most of these stemlines were also observed in other sites. These facts may suggest that polyclonal cancer cells rather than one cancer cell or monoclonal cancer cells of a Pri metastasize or infiltrate, and that various polyclonal cancer cells proliferate to different degrees under different circumstances.