Endoscopic ultrasound characteristics of mucinous cystic neoplasms of the pancreas

OBJECTIVE: Mucinous cystic neoplasms of the pancreas have a more favorable prognosis than ductal adenocarcinoma. Management of a subgroup, intraductal papillary-mucinous neoplasms, is controversial. Endoscopic ultrasound (EUS) with fine-needle aspiration biopsy may emerge as the imaging modality of choice. There are few studies describing the EUS features of these tumors. METHODS: A total of 35 consecutive cases of cystic tumors of the pancreas with an established pathological diagnosis were analyzed for characteristic EUS features. RESULTS: Mucinous cystadenocarcinomas (n = 14) were more likely to be characterized by hypoechoic cystic/solid mass or complex cyst and were frequently associated with a dilated main pancreatic duct. Benign mucinous duct ectasia (n = 6) were characterized by a dilated main pancreatic duct in conjunction with hyperechoic thickening of the duct wall. The two cases of intraductal mucinous hyperplasia additionally showed a hypoechoic mass. Intraductal papillary carcinoma (n = 11) had features in common with mucinous cystadenocarcinoma but also had echogenic foci in the mass and intraductal hyperechoic lesions. The two cases of microcystic cystadenoma showed either a mixed hypoechoic solid/cystic mass or a complex cyst without the additional features seen in mucinous cystadenocarcinoma. CONCLUSIONS: EUS features seem to exist that may help to differentiate cystic neoplasms from adenocarcinoma of the pancreas and, thus, to establish the preoperative diagnosis of cystic tumors of the pancreas.     

Malignant serous cystic neoplasm of the pancreas: report of a case and review of the literature

BACKGROUND: In general, serous cystic neoplasms of the pancreas are thought to be benign. Malignant serous cystic neoplasm of the pancreas is a rare clinical entity. CASE REPORT: We report the case of an 87-year-old woman with a serous microcystic neoplasm in the tail of the pancreas that behaved in a malignant fashion. The neoplasm had also invaded the colonic mesentery and splenic hilum. The pancreatic lesion was diagnosed as a large malignant serous cystic neoplasm, and the patient underwent distal pancreatectomy with splenectomy and segmental colectomy. The resected specimen contained a large tumor, 12 x 9 x 8 cm, which occupied the body and tail of the pancreas. Histologically, the tumor was indistinguishable from serous cystadenoma. However, the tumor had invaded surrounding tissues including the splenic vein, and there were splenic invasion and a regional lymph node metastasis. The postoperative course was uneventful. DISCUSSION: There are few reported cases of malignant serous cystic neoplasm, in which malignancy was histologically confirmed in the resected specimen. There are no reports of a negative outcome with complete resection of the tumor. Surgical treatment should be considered for serous cystic neoplasms, especially large ones, because of the malignant potential.     

Cystic lesions in the pancreas: When to watch, when to resect

The diagnosis of cystic lesions in the pancreas is becoming more common, largely due to the increases in diagnostic imaging done for other reasons. This review considers pseudocysts, mucinous cystic neoplasms, intraductal papillary mucinous tumors, and serous cystadenomas in some detail. The emphasis is on the fact that, through a careful history, physical examination, radiologic studies, and, often, cyst fluid analysis, a diagnosis can be reached expeditiously. This pursuit is important because two thirds of pancreatic cystic neoplasms are malignant or premalignant and should be resected, whereas pseudocysts and serous cystadenomas are benign, and, depending on the case, may be treated through observation, resection, or, for pseudocysts, by internal drainage.     

Risk of malignancy in serous cystic neoplasms of the pancreas

BACKGROUND: In contrast to mucinous cystic neoplasms of the pancreas, which are known to have considerable malignant potential, the serous variant is generally thought to be benign. There are, however, several reports of malignancy in serous cystic neoplasms of the pancreas. AIMS: To assess the risk of malignancy of serous cystic tumors of the pancreas and to investigate specific clinical and histological features. METHODS: Clinical and pathological characteristics of benign and malignant serous cystic neoplasms of the pancreas were investigated by a review of the literature and documented by a case of a serous cystadenocarcinoma and immunohistochemical analysis of a series of serous cystadenomas. Reviewing the literature prevalence, age and sex distribution of serous cystic neoplasms were analyzed. RESULTS: The prevalence of cancer among serous cystic neoplasms reported since 1989 was 3%. Serous cystadenoma of the pancreas present at an earlier age (61 years) than serous cystadenocarcinoma (66 years; p = 0.056) and are symptomatic in the majority of patients.Pathological examination of the primary tumor was not able to distinguish cystadenoma from cystadenocarcinoma in 38% of cases. In 25% the diagnosis of cancer was established only after growth of metachronous metastases. In the present case, nuclear atypia, papillary structures, proliferation marker Ki-67 and p53 protein were increased in the primary tumor and/or metachronous metastasis. CONCLUSION: Serous cystic neoplasms of the pancreas do have malignant potential with a risk of malignancy of 3% and should be surgically treated if the operative risk is acceptable. Routine analysis of genetic and proliferation markers may improve diagnosis of malignancy in these tumors.     

A discrepant finding between magnetic resonance imaging and other imaging modalities suggests a microcystic serous cystadenoma of the pancreas.

BACKGROUND: Serous cystadenoma of the pancreas is generally considered as having no malignant potential. Thus, of clinical importance is a differential diagnosis of this neoplasm from other solid tumors that are often malignant. RESULTS: We report a case of microcystic serous cystadenoma of the pancreas. Abdominal ultrasonography, computed tomography, and endoscopic ultrasonography showed a solid mass in the body of the pancreas with a diameter of 15 mm, but magnetic resonance imaging revealed it as a unilocular cystic lesion. Histological examinations on the surgically resected tissue specimen showed a honeycombed tumor with innumerable tiny cysts appearing grossly as a solid mass. The discrepant finding between magnetic resonance imaging and other imaging modalities observed in this case is suggestive of and might be specific to microcystic serous cystadenoma of the pancreas. CONCLUSIONS: Magnetic resonance imaging is a mandatory modality to identify pancreatic serous cystadenoma that contains no visible cystic compartments on computed tomography and ultrasonography.     

Cystic pancreas adenoma. On the clinical relevance of histologic typing

Although pancreatic cystadenomas are rare neoplasms, they are found today in rising frequencies due to improvement of diagnostic tools. There exist two types of cystadenoma: microcystic serous cystadenoma and mucinous cystadenoma. Usually, histological distinction from cystadenocarcinoma is readily made, but it may be difficult in the case of the mucinous variant. This subtype is supposed to be potentially malignant, whereas microcystic serous cystadenoma is always benign. In order to elucidate the characteristics of both variants, 5 own cases are reported in this article.     

A discrepant finding between magnetic resonance imaging and other imaging modalities suggests a microcystic serous cystadenoma of the pancreas

Summary Background. Serous cystadenoma of the pancreas is generally considered as having no malignant potential. Thus, of clinical importance is a differential diagnosis of this neoplasm from other solid tumors that are often malignant. Results. We report a case of microcystic serous cystadenoma of the pancreas. Abdominal ultrasonography, computed tomography, and endoscopic ultrasonography showed a solid mass in the body of the pancreas with a diameter of 15 mm, but magnetic resonance imaging revealed it as a unilocular cystic lesion. Histological examinations on the surgically resected tissue specimen showed a honeycombed tumor with innumerable tiny cysts appearing grossly as a solid mass. The discrepant finding between magnetic resonance imaging and other imaging modalities observed in this case is suggestive of and might be specific to microcystic serous cystadenoma of the pancreas. Conclusions. Magnetic resonance imaging is a mandatory modality to identify pancreatic serous cystadenoma that contains no visible cystic compartments on computed tomography and ultrasonography.     

Magnetic resonance imaging in the detection of pancreatic neoplasms

Recently, with the rapid scanning time and improved image quality, outstanding advances in magnetic resonance (MR) methods have resulted in an increase in the use of MRI for patients with a variety of pancreatic neoplasms. MR multi-imaging protocol, which includes MR cross-sectional imaging, MR cholangiopancreatography and dynamic contrast-enhanced MR angiography, integrates the advantages of various special imaging techniques. The non-invasive all-in-one MR multi-imaging techniques may provide the comprehensive information needed for the preoperative diagnosis and evaluation of pancreatic neoplasms. Pancreatic neoplasms include primary tumors and pancreatic metastases. Primary tumors of the pancreas may be mainly classified as ductal adenocarcinomas, cystic tumors and islet cell tumors (ICT). Pancreatic adenocarcinomas can be diagnosed in a MRI study depending on direct evidence or both direct and indirect evidence. The combined MRI features of a focal pancreatic mass, pancreatic duct dilatation and parenchymal atrophy are highly suggestive of a ductal adenocarcinoma. Most cystic neoplasms of the pancreas are either microcystic adenomas or mucinous cystic neoplasms. Intraductal papillary mucinous tumors are the uncommon low-grade malignancy of the pancreatic duct. ICT are rare neoplasms arising from neuroendocrine cells in the pancreas or the periampullary region. ICT are classified as functioning and non-functioning. The most frequent tumors to metastasize to the pancreas are cancers of the breast, lung, kidney and melanoma. The majority of metastases present as large solitary masses with well-defined margins.     

An extremely rare cause of acute abdomen in pregnancy: ruptured pancreatic mucinous cystadenocarcinoma

Pancreatic cystadenocarcinoma is an extremely rare neoplasm in pregnancy. To our knowledge, there have been 2 published cases of pancreatic mucinous cystadenocarcinoma (PMC) during pregnancy in the literature; one of which was reported to have ruptured into the abdominal cavity. We present a second case of ruptured PMC resulting in acute abdomen in 36 weeks of pregnancy. Rupture of mucinous cystic neoplasms of pancreas including PMC should be remembered in acute abdomen during pregnancy.     

Management of the rare entity of primary pancreatic cystic neoplasms

Primary cystic neoplasms of the pancreas constitute a rare entity and are composed of a variety of neoplasms with a wide range of malignant potential. Approximately 90% of these lesions are serous cystic neoplasms or mucin-producing neoplasms. In contrast to serous cystadenomas which are nearly always benign, the mucinous cystic neoplasms represent a more diverse, heterogenous spectrum of related neoplasms. Intraductal papillary mucinous neoplasms manifest a much greater latent or overt malignant potential than other cystic neoplasms of the pancreas. The various subgroups of cystic neoplasms of the pancreas are evaluated and compared through a review of current literature. No symptoms or signs are pathognomonic for the cystic pancreatic neoplasms. While identification of a cystic tumor is relatively easy, the identification of the specific tumor type may be difficult. Most investigators agree that accurate differentiation of benign from malignant neoplasms can be made only at histopathologic examination of the entire resected segment of the pancreas. Because of the low mortality and low postoperative morbidity, surgical resection is indicated in all patients with cystic tumors.     

Cystic neoplasms of the pancreas: a series.

MATERIAL AND METHODS: a series of 23 cases with cystic pancreatic neoplasms studied and treated between December 1977 and December 2001 out of 297 cases of pancreatic neoplasms is presented. RESULTS: 16/23 were true pancreatic cystic neoplasms: 9 microcystic adenomas and 6 mucinous cystoadenoma type. There were also 2 hydatid cysts, 1 lymphangioma, 2 cases of tuberculosis involving de pancreas, 1 lymphoma and 1 papillary cystic tumor type. CONCLUSIONS: true cystic tumors of the pancreas accounts for 5,8% of the neoplasms studied in our hospital.     

Serous cystic neoplasms of the whole pancreas in a patient with von Hippel-Lindau disease

We describe here a case of von Hippel-Lindau (VHL) disease with a serous cystic neoplasm of the whole pancreas. The patient was a 35-year-old woman suffering from a palpable abdominal tumor. She had a history of hemangioblastomas of the cerebellum. CT revealed large solid tumors in the pancreatic head and body, and multiple cystic lesions in the whole pancreas as well as a right renal tumor. When endoscopic retrograde cholangiopancreatography (ERCP) was performed, bleeding from the duodenal papilla was detected. Since she had some distinguishing clinical features, the diagnosis of VHL disease was made. The preoperative diagnosis of the pancreatic lesion was serous cystic neoplasms with hemosuccus pancreaticus and total pancreatectomy was performed. Histological examination of the specimen revealed serous cystic neoplasms which occupied the entire pancreas. VHL cases operated on for serous cystic neoplasms of the entire pancreas are very rare.     

Cystic ductal adenocarcinoma of pancreas: an unusual variant.

Cystic lesions of the pancreas are usually pseudocysts (90%); only 10% of them are cystic tumors. These cystic tumors constitute less than 10% of all pancreatic neoplasms, making them an extremely uncommon type of pancreatic malignancy. What is more important is that these tumors are very easily misdiagnosed as pseudocysts because their characteristics are very similar to those of the benign pseudocysts. This gains importance as the cystic tumors have a high cure rate and good prognosis if diagnosed and treated on time. Of all the cystic tumors, the most common are the benign serous cystadenomas, mucinous cystic tumors, intraductal papillary mucinous neoplasms etc. Ductal adenocarcinoma of pancreas presenting in cystic form is an uncommon type of cystic tumor, making it extremely rare among all pancreatic malignancies (solid or cystic). We present the following case report. The review of literature concerning the diagnosis and management has also been discussed.     

Resektion zystischer Pankreastumoren

Cystic tumors of the pancreas are diagnosed increasingly more due to increasing life expectancy and the moderate use of modern radiological diagnostics. Intraductal papillary mucinous neoplasms of the pancreas (IPMN), mucinous cystic neoplasms (MCN), solid pseudopapillary neoplasms (SPN) and serous cystic neoplasms (SCN) represent over 90?% of all cystic neoplasms of the pancreas. Although serous cystic lesions have a low or even no potential for malignant transformation, they are mostly resected when symptomatic. In contrast, mucinous lesions have an increased malignant potential and should therefore be resected in almost all cases. While this is true for all cases of MCNs and SPNs this is controversial for all IPMNs as they show a wide spectrum of morphological variants. The IPMNs may arise in the main pancreatic duct, major side branches or in both (mixed type). Although all IPMNs are considered to be precursor lesions to pancreatic adenocarcinomas it is not clear what the time course of such potential neoplastic transformation might be and whether all lesions progress to malignant tumors. As no currently used diagnostic test can reliably differentiate between benign and malignant tumors, the majority of newly diagnosed IPMNs should undergo surgical resection. According to current treatment guidelines (Sendai criteria), asymptomatic side branch IPMNs of less than 3 cm in diameter without suspicious radiological features, such as nodules, thickness of the cystic wall or size progression can be treated conservatively without the need for surgical resection. Recently, this approach has become controversial due to a relevant number of IPMNs reported as Sendai negative that showed malignant transformation on final histological examination.     

Diagnostic dilemmas in patients with cystic neoplasms of the pancreas

Cystic neoplasms of the pancreas (CNP) are rare lesions that can be difficult to diagnose preoperatively. Twenty patients with cystic neoplasms of the pancreas including five microcystic adenomas, six benign mucinous cystic neoplasms, three malignant mucinous cystic neoplasms, two solid and papillary epithelial neoplasms, and four cystic neuroendocrine tumors were treated at a single institution between 1962 and 1987. The average duration of symptoms prior to diagnosis was 10 months. Five patients were asymptomatic. Forty percent of patients presented with an abdominal mass. Plain abdominal x-rays and UGI barium contrast studies were never diagnostic. Ultrasonography, computerized tomography (CT) and visceral angiography aided in the correct diagnosis in 28%, 36%, and 75% of patients studied, respectively. Overall a correct diagnosis was made preoperatively in only 35% of patients. Twelve of 13 patients were correctly diagnosed at laparotomy with intraoperative biopsy. Without biopsy the mass was misdiagnosed at laparotomy in five of six cases. CNP must be suspected in any patients who present with an upper abdominal mass with or without abdominal pain and no history of pancreatitis. CT may be diagnostic in up to one third of cases and should be obtained routinely to demonstrate the proximity of the lesion to other structures. Visceral angiography should also be obtained prior to operation. A generous incisional biopsy should be obtained of all pancreatic cysts that are not to be resected.     

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.     

Intraductal papillary mucinous tumors and mucinous cystic tumors of the pancreas: imaging

Most cystic lesions of the pancreas are nonneoplastic and inflammatory in nature. However, approximately 5%–15% of cystic pancreatic masses may be neoplastic. Among the cystic neoplasms are the mucin-producing tumors, both the intraductal papillary mucinous neoplasms and the mucinous cystic neoplasms. Their imaging features on contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) can assist in the differentiation of these lesions. The imaging findings of both intraductal papillary mucinous neoplasm and mucinous cystic neoplasm are reviewed with attention to CT and MRI.     

Diagnostic dilemmas in patients with cystic neoplasms of the pancreas

Summary Cystic neoplasms of the pancreas (CNP) are rare lesions that can be difficult to diagnose preoperatively. Twenty patients with cystic neoplasms of the pancreas including five microcystic adenomas, six benign mucinous cystic neoplasms, three malignant mucinous cystic neoplasms, two solid and papillary epithelial neoplasms, and four cystic neuroendocrine tumors were treated at a single institution between 1962 and 1987. The average duration of symptoms prior to diagnosis was 10 months. Five patients were asymptomatic. Forty percent of patients presented with an abdominal mass. Plain abdominal x-rays and UGI barium contrast studies were never diagnostic. Ultrasonography, computerized tomography (CT) and visceral angiography aided in the correct diagnosis in 28%, 36%, and 75% of patients studied, respectively. Overall a correct diagnosis was made preoperatively in only 35% of patients. Twelve of 13 patients were correctly diagnosed at laparotomy with intraoperative biopsy. Without biopsy the mass was misdiagnosed at laparotomy in five of six cases. CNP must be suspected inany patients who present with an upper abdominal mass with or without abdominal pain and no history of pancreatitis. CT may be diagnostic in up to one third of cases and should be obtained routinely to demonstrate the proximity of the lesion to other structures. Visceral angiography should also be obtained prior to operation. A generous incisional biopsy should be obtained of all pancreatic cysts that are not to be resected.     

MRI对胰腺囊性肿瘤的诊断价值

目的探讨MRI对胰腺囊性肿瘤的诊断价值。方法回顾分析23例经手术病理证实的胰腺囊性肿瘤资料,总结其影像表现。结果黏液性囊性肿瘤10例,囊性肿块较大,肿块平均直径超过10 cm,由较厚的纤维壁分隔成多房囊肿,外壁光滑,边界清楚。浆液性囊腺瘤6例,病灶较小,囊内有分隔而呈放射状排列,中心瘢痕为其特征性表现。胰腺囊性转移瘤3例,均有肿瘤病史,表现不典型,需结合肿瘤病史定性。胰胚细胞瘤2例,幼儿发病,肿块巨大,肿瘤坏死囊变,形成假-假性囊肿。胰腺乳头状囊实性肿瘤1例,表现为边界清楚的囊实性肿块,囊壁上有壁结节。胰腺毛细血管瘤1例,表现与浆液性囊腺瘤相似,难以术前诊断。结论MRI对胰腺囊性肿瘤具有高度敏感性,不同病变有一定的特征性表现, 对术前定性极有价值。