Expression of CA 72-4 (TAG-72) in the fluid contents of pancreatic cysts. A new marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts

Intraductal papillary mucinous neoplasms of the pancreas: is the puzzle solved?

Intraductal papillary mucinous neoplasms (IPMN) are drawing more attention and being detected more frequently. This review focuses on current understanding of the management of IPMN, regarding morphological classification, subclassification by cell lineage features, molecular abnormalities, radiological and imaging evaluation, progression to cancer, incidence and risk factors for malignancy, risk of distinct pancreatic adenocarcinoma and extrapancreatic malignancies, treatment strategy, and types of surgical resection. In particular, missing links in solving the IPMN puzzles are described with regard to differential diagnosis, role of cyst fluid analysis, multifocal IPMN, histological evaluation of the surgical specimen, observation without resection, follow up of patients after resection, role of adjuvant therapy for invasive carcinoma, screening for other neoplasms in patients with IPMN on follow up, prognostic factors influencing long-term outcomes, and role of endoscopic therapy.

[History of tumor markers for cancers of the digestive system]

Tumor markers are gene products which signal the occurrence of tumors in different organs as well as their response to surgery and chemotherapy. The discovery of tumor markers occurred after the demonstration of tumor-specific transplantation antigens in chemically or virally induced tumors in syngenic rodents. The history of currently used tumor markers began in the 1940s, the first discovered being alpha-fetoprotein in 1956, followed by that of carcinoembryonic antigen in 1965. Since then the range of tumor markers has widened continously. Their chemical structure and genetics is now well known. Some may play part in tumor growth and development of metastases. The potential uses of tumor markers are general or high risk population screening, adjunct in diagnosis of cancer, preoperative indicator of tumor burden, indicator of therapeutic success, evidence of postoperative recurrences and use in tumor localization. However, there is no ideal tumor marker fulfilling all the criteria. Isotope-labeled anti-carcinoembryonic antigen antibodies and small molecular E-selectin inhibitors could play a role in the molecular radio- and chemotherapy of colon and pancreatic carcinomas.

Advances in the diagnosis of cystic neoplasms of the pancreas

PURPOSE OF REVIEW

Management of pancreatic cystic neoplasms is challenging due to limitations of current diagnostic tests. There is considerable interest in developing an accurate and cost-effective diagnostic test (or panel of tests) to differentiate cyst types and to identify those which would benefit most from surgical resection.

RECENT FINDINGS

Current multidetector computed tomography scans may have improved accuracy to distinguish between mucinous and nonmucinous cysts. Attempts to generate quantitative criteria from cross-sectional imaging to differentiate cyst types have yielded mixed results. DNA mutations and microRNA show promise in the ability to distinguish between mucinous and nonmucinous cysts. Cyst fluid mucin glycoproteins and cytokines may identify those cysts with high malignant potential. Proteomic analysis may yield other biomarker candidates.

SUMMARY

Analysis of DNA mutations and proteins within pancreatic cyst fluid have identified potential biomarkers to aid with the management of patients with pancreatic cystic neoplasms.

New trends in diffusion-weighted magnetic resonance imaging as a tool in differentiation of serous cystadenoma and mucinous cystic tumor: a prospective study

BACKGROUND/AIMS

Pancreatic cystic lesions are increasingly being recognized. Magnetic resonance imaging (MRI) is the method that brings the greatest amount of information about the morphologic features of pancreatic cystic lesions. To establish if diffusion-weighted MRI (DW-MRI) can be used as a tool to differentiate mucinous from nonmucinous lesions.

METHODS

Fifty-six patients with pancreatic cystic lesions (benign, n = 46; malignant, n = 10) were prospectively evaluated with DW-MRI in order to differentiate mucinous from nonmucinous lesions. Final diagnosis was obtained by follow-up (n = 31), surgery (n = 16) or endoscopic ultrasound-guided fine needle aspiration (n = 9). Serous cystadenoma was identified in 32 (57%) patients.

RESULTS

The threshold value established for the differentiation of mucinous from nonmucinous lesions was 2,230.06 s/mm(2) for ADC of 700. DWI-MRI behavior between mucinous and nonmucinous groups revealed sensitivity, specificity, positive predictive value, negative predictive value and accuracy to be 80, 98, 92, 93 and 93%, respectively (p < 0.01, power of sample = 1.0). In the comparison of the diffusion behavior between mucinous (n = 13) and serous (n = 32) lesions, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 100, 97, 92, 100 and 98%, respectively (p < 0.01, power of sample = 1.0). The results of endoscopic ultrasound-guided fine needle aspiration were similar to those of DW-MRI.

CONCLUSIONS

DW-MRI can be included as part of the array of tools to differentiate mucinous from nonmucinous lesions and can help in the management of pancreatic cystic lesions. and IAP.

The use of protein-based biomarkers for the diagnosis of cystic tumors of the pancreas

Proteomics is a powerful method used to identify, characterize, and quantify proteins within biologic samples. Pancreatic cystic neoplasms are a common clinical entity and represent a diagnostic and management challenge due to difficulties in accurately diagnosing cystic lesions with malignant potential and assessing the risk of malignant degeneration. Currently, cytology and other biomarkers in cyst fluid have had limited success in accurately distinguishing both the type of cystic neoplasm and the presence of malignancy. Emerging data suggests that the use of protein-based biomarkers may have greater utility in helping clinicians correctly diagnose the type of cyst and to identify which cystic neoplasms are malignant. Several candidate proteins have been identified within pancreatic cystic neoplasms as potential biomarkers. Future studies will be needed to validate these findings and move these biomarkers into the clinical setting.

Controversies in the management of pancreatic IPMN

Although considerable progress has been made in our understanding of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, some issues still remain to be resolved. Uncertainty exists regarding the classification of IPMNs. The necessity of the mixed-type category of IPMN and whether such lesions should be defined radiographically or histologically needs to be determined. The preoperative distinction of branch duct IPMNs from nonmucinous cysts should be further investigated so that potentially malignant lesions can be identified and management strategies guided effectively. The role and safety of cystic fluid analysis remains to be clarified in this context. With regard to the diagnosis of malignancy in branch duct IPMNs, criteria for identifying malignancy need to be re-evaluated. The presence of mural nodules is a very reliable predictor; however, controversy exists over the value of size as a reliable indicator. Criteria with increased specificity are needed, perhaps including histological subtype of lesion, to reduce the false-positive rate of the present criteria. Finally, the best modality and interval for surveillance of branch duct IPMNs requires determination because of its significance in terms of malignant transformation, development of distinct ductal adenocarcinoma and disease recurrence after resection.

Parallel in vivo and in vitro selection using phage display identifies protease-dependent tumor-targeting peptides

We recently developed activatable cell-penetrating peptides (ACPPs) that target contrast agents to in vivo sites of matrix metalloproteinase activity, such as tumors. Here we use parallel in vivo and in vitro selection with phage display to identify novel tumor-homing ACPPs with no bias for primary sequence or target protease. Specifically, phage displaying a library of ACPPs were either injected into tumor-bearing mice, followed by isolation of cleaved phage from dissected tumor, or isolated based on selective cleavage by extracts of tumor versus normal tissue. Selected sequences were synthesized as fluorescently labeled peptides, and tumor-specific cleavage was confirmed by digestion with tissue extracts. The most efficiently cleaved peptide contained the substrate sequence RLQLKL and labeled tumors and metastases from several cancer models with up to 5-fold contrast. This uniquely identified ACPP was not cleaved by matrix metalloproteinases or various coagulation factors but was efficiently cleaved by plasmin and elastases, both of which have been shown to be aberrantly overexpressed in tumors. The identification of an ACPP that targets tumor expressed proteases without rational design highlights the value of unbiased selection schemes for the development of potential therapeutic agents.

Current trends in pancreatic cystic neoplasms

OBJECTIVE

To define how patients with pancreatic cysts are being diagnosed and treated.

DESIGN

Retrospective case series.

SETTING

University-affiliated tertiary care center.

PATIENTS

Four hundred one patients evaluated in the Department of Surgery between January 2004 and December 2007.

MAIN OUTCOME MEASURES

Clinical management, histological diagnosis, and results of surveillance.

RESULTS

Pancreatic cysts were incidentally discovered in 71% (284 of 401) of patients. There was no statistically significant difference in age (60.4 vs 63.1 years; P = .10), cyst size (31 vs 27 mm; P = .12), or histological diagnosis between symptomatic patients and patients with incidentally discovered cysts. Whereas the majority of symptomatic patients had their cystic neoplasms resected on diagnosis, 50% (142 of 284) of incidentally discovered cysts were initially managed nonoperatively. Of the patients who were managed with surveillance, 13 (8%) subsequently underwent resection after a median of 2.1 years because of an increase in cyst size, development of symptoms, increasing tumor markers, worrisome endoscopic ultrasonography findings, or patient anxiety. The most common diagnosis among resected lesions was either main-duct intraductal papillary mucinous neoplasm (25%) or branch-duct intraductal papillary mucinous neoplasm (23%). Invasive cancer was found in 29 of 256 (11%) resected cystic neoplasms, 9 of which were incidentally discovered, and in 7% (1 of 13) of patients who underwent watchful waiting prior to resection.

CONCLUSIONS

Incidentally discovered pancreatic cystic neoplasms composed 71% of our series, of which 50% were immediately resected. Subsequent morphologic changes or development of symptoms prompted an operation in 8% of patients after a period of surveillance. Invasive malignancy was present in 11% of all resected specimens but in 38% of main-duct intraductal papillary mucinous neoplasms.

Cystic Neoplasms of the Pancreas: Current Diagnostic Modalities and Management

Cystic neoplasm of the pancreas is a relatively uncommon condition covering a wide spectrum of pathology. The increasing incidence as a result of routine imaging tests in asymptomatic patients presents a diagnostic and therapeutic problem to the clinician. This paper discusses the role of the various investigative modalities in the management of cystic neoplasia of the pancreas. Key words: Frantz tumour, Intraductal papillary mucinous neoplasm, Mucinous cystadenoma, Mucinous cystadenocarcinoma, Mucinous neoplasm of the pancreas, Solid pseudopapillary neoplasm

Cystic pancreatic tumors (CPT): predictors of malignant behavior

BACKGROUND AND OBJECTIVES

Due to widespread use of imaging studies, increasing cystic pancreatic tumor (CPT) cases are being detected. The diagnosis of malignancy in CPT cases requires pancreatectomy. Clinical and laboratory characteristics of CPT may predict underlying malignancy.

METHODS

CPT cases treated between 1994 and 2004 at our institution were included. Pseudocysts were excluded. Serous cystadenoma (SCA), mucinous cystadenoma (MCA), intrapapillary mucinous tumor, cystic endocrine tumor, and lymphoepithelial cysts were classified as benign or pre-malignant. Serous cystadenocarcinoma (SCACA), mucinous cystadenocarcinoma (MCACA), and adenocarcinoma (ACA) were classified as malignant.

RESULTS

Thirty-five patients had histological confirmation. Median age was 65 years. Male/female ratio was higher in malignant group (P = 0.0284). Weight loss and abdominal mass were more prevalent in malignant group (P = 0.042 and 0.028, respectively). Malignant lesions were larger, associated with local invasion (superior mesenteric artery (SMA), superior mesenteric vein (SMV), portal vein (PV) complex or celiac encasement) and CA 19-9 elevation. On univariate analyses, local invasion (P = 0.0029), negative surgical intervention (P = 0.0010), presence of ACA (P = 0.0044), or malignant CPT (P = 0.0018) were associated with shorter survival. On a multivariate analysis, local invasion was associated with shorter survival [Hazard ratio (HR) = 4.322, P = 0.0218], while surgical intervention was associated with improved survival (HR = 0.179, P = 0.0124).

CONCLUSION

Male sex, abdominal mass, weight loss, larger tumor size, local invasion, and elevated CA 19-9 were associated with malignant CPT.

Cystic tumours of the pancreas

Pancreatic carcinoma accounts for the most dismal survival among all malignancies with 5-year survival rates approaching 5%. The reason for this, besides the inherent biologic nature of the disease, is the fact that the patients tend to present late in the disease. We present a review of the current published data on cystic neoplasms of the pancreas, which though rare, constitute an important subgroup of pancreatic neoplasms that have a better prognosis and are potentially curable lesions.

Natural history of indeterminate pancreatic cysts

BACKGROUND

The optimal treatment for incidental asymptomatic pancreatic cysts is not known. The purpose of this study was to determine whether nonmucinous cysts by cyst-aspiration analysis can be observed safely.

METHODS

A prospective protocol was initiated in September of 1999 for all suspected cystic neoplasms. Asymptomatic patients with negative cyst aspirates (no extracellular mucin, and concentration of carcinoembryonic antigen in the cyst fluid <200 ng/mL) were followed-up clinically and radiographically.

RESULTS

Through December 2004, 221 patients have been evaluated, and 80 (36%) initially were operated. There were 141 (64%) patients with indeterminate cysts, 98 have been followed-up for more than 12 months. Compared with resected patients, observed patients were older (62 vs 56 y, P < .006), and had smaller cysts (2.4 vs 4.0, P = .001). At a mean follow-up period of 24 months, 4 patients (4%) were resected. The indication, time to resection, and pathology were as follows: 2 patients for symptoms (abdominal pain and obstructive jaundice) at 24 and 72 months, respectively: mucinous and serous cystadenomas; 1 patient for an increase in size (6.6 to 7.8 cm) at 18 months: lymphoepithelial cyst; and 1 patient for abdominal pain and increase in size (2.0 to 3.7 cm) at 41 months: pseudocyst. The only patient resected for a mucinous neoplasm had a cyst fluid carcinoembryonic antigen level of 896 ng/mL. In the remaining observed patients, 20 (23%) showed a decrease in cyst size, and 16 (19%) showed an increase in size (mean diameter change, 21%).

CONCLUSIONS

Initial follow-up evaluation indicates that asymptomatic patients without evidence of a mucinous neoplasm by cyst aspiration can be followed clinically and with interval imaging.

Pancreatic endocrine tumor coexistent with serous microcystic adenoma: report of a case and review of the literature

Serous cystadenomas of the pancreas have been classified as benign exocrine tumors. There have been rare cases of malignant behavior, and in exceptional cases, coexisting neoplasms have been reported. We report a case of a coexistent neuroendocrine tumor identified within a serous cystadenoma in a 78-year-old woman, which was discovered incidentally after complete resection of the tumor. Given the unpredictable metastatic potential of neuroendocrine tumors of the pancreas, we advocate complete resection of all pancreatic cystic tumors, combined with careful sampling of the pathological specimen to rule out a coexistent potentially malignant neoplasm.

Management of cystic tumours of the pancreas

BACKGROUND

Cystic tumours of the pancreas account for 5% of pancreatic neoplasms and are frequently misdiagnosed as pancreatic pseudocysts. The authors' experience of managing these tumours is presented here, highlighting the clinical presentation, diagnostic difficulties and operative treatment.

METHODS

This is a retrospective study of all patients diagnosed to have cystic tumours of the pancreas treated at The Mater Hospital, during a 5-year period from 1997 to 2002. Literature was reviewed and guidelines for the management of these tumours have been outlined.

RESULTS

Seven patients with cystic pancreatic tumours were treated over this time-period. All patients were women with a median age of 40. Two of these patients were initially diagnosed as having pseudocysts and were treated elsewhere by cystgastrostomy. The tumour was resected in all patients. All but one was benign. At follow up, ranging from 13 to 66 months, all patients were alive and well.

CONCLUSIONS

Cystic tumours of the pancreas are uncommon and generally slow growing. It is important not to assume that a cystic lesion in the pancreas, especially in middle-aged women, is a pseudocyst. Satisfactory surgical resection may be possible even after previous operative procedures on the pancreas. Prognosis after resection remains good.

Evaluation and management of cystic pancreatic tumors: emphasis on the role of EUS FNA

Cystic lesions of the pancreas are increasingly recognized and usually represent pseudocysts or cystic pancreatic tumors (CPTs), but also include congenital cysts, acquired cysts, extrapancreatic cysts, or cystic degeneration of solid tumors. It is important to distinguish CPT lesions given their varied prognosis and therapy. Mucinous varieties of CPTs (mucinous cystic neoplasms and intraductal papillary mucinous tumors) are premalignant or malignant, and surgical resection is generally recommended in good operative candidates. In contrast, nonmucinous CPTs include serous cystadenomas with a very low malignant potential, or pseudocysts, which are always benign. As a result, nonmucinous CPTs are generally resected only when inducing symptoms or complications. Review of the clinical, imaging, laboratory, and pathology information may clarify the specific tumor type. The relatively limited accuracy of any one modality requires that we consider the combined results when making management decisions.

Macrocystic pancreatic cystadenoma: The role of EUS and cyst fluid analysis in distinguishing mucinous and serous lesions

BACKGROUND

Benign pancreatic serous cystadenoma usually is morphologically distinguishable from mucinous cystadenomas, which require resection because of their malignant potential. A macrocystic variant of serous cystadenoma recently has been described, rendering this important distinction more difficult. The aim of this study was to determine the EUS and tumor marker characteristics of mucinous cystadenoma compared with macrocystic serous cystadenomas.

METHODS

Medical records for consecutive patients seen between 1995 and 2002, with a histopathologic diagnosis of mucinous cystadenoma or macrocystic serous cystadenoma after surgery, who had undergone a detailed EUS examination, including EUS-guided FNA, were retrospectively reviewed.

RESULTS

A resection specimen was available for 32 mucinous cystadenomas and 9 macrocystic serous cystadenomas. No significant differences were observed with regard to clinical data (age, gender, presence of symptoms), lesion size, and location within the pancreas. All mucinous cystadenomas had a discernible cyst wall (thickened, 66%; focal parietal nodules, 25%) compared with 56% of macrocystic serous cystadenomas (p<0.0001). A thick echo content also was more frequent in mucinous cystadenoma (56% vs. 11%; p=0.04; statistical significance removed by the Bonferroni correction). Microcysts were only observed in macrocystic serous cystadenomas (44%; p=0.0008). The combination of a cyst wall that is thickened and the absence of microcysts had a sensitivity of 100% and specificity of 78% for the diagnosis of mucinous cystadenoma compared with macrocystic serous cystadenoma. Although intracystic carbohydrate-associated antigen 72-4 and mucins M1 were non-discriminatory, low carcinoembryonic antigen (<5 ng/mL) and carbohydrate-associated antigen 19-9 (<50,000 U/mL) values were found in macrocystic serous lesions (respectively, 100% and 100%; p=0.0002 and p=0.0002).

CONCLUSIONS

Although there is considerable overlap, helpful EUS characteristics that differentiate mucinous cystadenoma from macrocystic serous cystadenoma include a thick cyst wall and microcysts. These features, coupled with analysis of aspirated fluid for tumor markers (especially carcinoembryonic antigen), should help to confirm the diagnosis.

Cystic pancreatic neoplasms: observe or operate

OBJECTIVE

The objectives of this analysis were to define the incidence, natural history, and predictors of neoplasia in pancreatic cysts to determine which patients can safely be observed and which should undergo an operation.

SUMMARY BACKGROUND DATA

With advancements in imaging technology, cystic lesions of the pancreas are being detected with increased frequency. Many of these lesions are small and asymptomatic, but they may be associated with pancreatitis or have malignant potential. Therefore, the management of these patients is complex, and knowledge of pancreatic cyst natural history and predictors of neoplasia are important.

METHODS

From January 1995 through December 2002, all radiologic, surgical, and pathology records were reviewed for the presence of pancreatic cysts. In determining natural history, only patients with 2 scans more than 1 month apart at our institution were included. Patients with a clinical history and laboratory evidence of pancreatitis and/or pathologic confirmation of a pseudocyst were excluded. Factors analyzed as potential predictors of neoplasia included age, gender, cyst size, and symptoms. Serous cystadenomas, solid and cystic papillary (Hamoudi) tumors, lymphoepithelial cysts and simple cysts were all benign, whereas mucinous cystic neoplasms, intraductal papillary mucinous neoplasm, cystic neuroendocrine tumors, and cystadenocarcinomas were considered to be premalignant or malignant.

RESULTS

Among 24,039 CT or MR scans, 290 patients (1.2%) had pancreatic cysts, and 168 of these patients (0.7%) had no documentation of pancreatitis. Seventy-nine of these patients with 103 cysts had more than 1 scan with an average interval of 16 months. These cysts increased in size in 19%, did not change in 59% and decreased in 22% of patients. Forty-nine patients underwent surgery for 14 benign (serous cystadenomas = 10, Hamoudi = 2, lymphoepithelial = 1, simple = 1) 25 premalignant (mucinous cystic neoplasm =16, intraductal papillary mucinous neoplasm = 5, neuroendocrine tumors = 4), or 10 malignant (intraductal papillary mucinous neoplasm = 7, cystadenocarcinomas = 3) lesions. Gender and cyst size did not predict neoplasia. However, presence of symptoms predicted premalignant or malignant pathology (60% vs. 23%, P < 0.05), and age over 70 years was associated with malignancy (60% vs. 21%, P < 0.02).

CONCLUSIONS

These data suggest that cystic pancreatic neoplasms 1) occur in 0.7% of patients, 2) increase in 19% over 16 months, and 3) are likely (60%) to be malignant in patients older than 70 years. Therefore, we recommend surgical excision for pancreatic cysts that are increasing under observation, symptomatic, or detected radiologically in fit older patients.

The role of preoperative biopsy in pancreatic cancer

BACKGROUND

Cyto-histological diagnosis of pancreatic pathology in the management of suspected pancreatic malignancy is re-evaluated in the light of evolving trends in management and tissue sampling.

METHODS

The literature on cyto-histological diagnosis of pancreatic pathology was reviewed over the period 1977-2003.

RESULTS AND CONCLUSION

Endoluminal techniques of tissue sampling carry less risk of tumour seeding and are the sampling methods of choice for potentially resectable lesions if a tissue diagnosis will alter therapy. Endosonar-guided biopsy in expert hands appears to be the most reliable tissue sampling technique. Transcoelomic sampling methods should be reserved for those with un-resectable disease. All methods of cyto-histological diagnosis have high specificity but have a low negative predictive value. Therefore, potentially resectable lesions that are highly suspicious for malignancy should be explored even if pre-operative histology or cytology is negative.

Serous oligocystic adenoma of the pancreas

Cystic neoplasms of the pancreas are uncommon lesions but are becoming increasingly prevalent. Herein we report a case of an oligolocular cystic lesion in the head of the pancreas in a young female that had undergone a cystenteroanastomosis 10 years ago. She underwent a duodenopancreatectomy with an uneventful recovery. The histology showed a serous oligocystic adenoma of the pancreas and the immunohistochemistry study confirmed the diagnosis. There is no sign of recurrence after the surgery. The role of pre-operative diagnosis based on tomographic, echoendoscopy and fine needle aspiration are discussed.

Cystic pancreatic neoplasms: enucleate or resect?

Asymptomatic cystic pancreatic neoplasms are being detected by abdominal imaging with increasing frequency. Enucleation of small cystic neoplasms can be performed without recurrence but has been associated with a higher incidence of pancreatic fistula. Thus the procedure has been modified to include intraoperative ultrasound imaging and closure of the pancreatic defect. This analysis was performed to determine whether these modifications have improved operative outcome. Thirty patients with mucinous cystic neoplasms (n=16), serous cystadenomas (n=10), and cystic islet cell tumors (n=4) were studied. Enucleation was performed in 11 patients (7 with mucinous cystic neoplasms, 2 with serous cystadenomas and 2 with islet cell tumors), whereas 19 underwent resection of cystic tumors (pancreatoduodenectomy in 8 and distal pancreatectomy in 11). The mean groups did not differ with regard to age (57 years), gender (73% female), presentation (63% incidental), or site (43% head, neck, or uncinate). Patients undergoing enucleation had smaller tumors (2.2 vs. 4.7 cm, P<0.01) that were less likely to be in the tail (9% vs. 42%). Operative time was significantly shorter in the enucleation group (199 vs. 298 minutes, P<0.01). Blood loss also was significantly reduced in the enucleation group (114 vs. 450 ml, P<0.001). Pancreatic fistula rates (27% vs. 26%) and length of hospital stay (12.6 vs. 15.7 days) were similar in the two groups. Enucleation of benign cystic pancreatic neoplasms reduces operative time and blood loss without increasing postoperative complications or length of stay. Therefore enucleation should be the standard operation for small benign cystic neoplasms in the uncinate, head, neck, and body of the pancreas.

Aspectos ultra-sonográficos da neoplasia epitelial papilífera sólido-cística do pâncreas

Os autores relatam os aspectos clínicos, macroscópicos e ultra-sonográficos em 11 pacientes com neoplasia epitelial papilífera sólido-cística (NEPSC) de pâncreas avaliados prospectivamente. Dez pacientes eram do sexo feminino e um era do sexo masculino, com idades entre 15 e 75 anos (média de 27 anos). Todos os pacientes tiveram diagnóstico de NEPSC de pâncreas comprovado por exame histopatológico e foram submetidos a exames de ultra-sonografia no pré-operatório. Foram avaliadas as dimensões, a localização e os aspectos ultra-sonográficos dos tumores, realizando-se correlação com suas características macroscópicas. O diâmetro transverso médio das lesões foi de 8,7 cm (variação: 4,2 a 16,0 cm). Três localizavam-se na cabeça, três no corpo e cinco na cauda do pâncreas. Todas as lesões tinham algum grau de hemorragia intratumoral e eram bem delimitadas e encapsuladas. Em todos os casos houve correlação completa entre o aspecto macroscópico dos tumores com os achados da ultra-sonografia. Os tumores eram predominantemente sólidos em três casos (27,3%), císticos em um (9,1%) e com aspecto sólido-cístico em sete (63,6%). Foram identificadas calcificações, predominantemente periféricas, em quatro (36,4%) dos 11 pacientes. Todos os tumores estabeleciam contato com algum segmento do eixo venoso espleno-mesentérico-portal. Em apenas um caso foi confirmada invasão vascular tumoral. Não foram identificadas metástases ganglionares ou a distância em nenhum paciente. Os autores concluem que as características ultra-sonográficas se correlacionaram com os aspectos macroscópicos das lesões em todos os casos, e que, embora não-específicas, elas são bastante sugestivas do diagnóstico de NEPSC se analisadas no contexto clínico apropriado.

Macrocystic form of serous pancreatic cystadenoma

OBJECTIVES

Macrocystic serous cystadenoma of the pancreas are benign lesions with sometimes difficult diagnostic issues. We aimed to describe clinicopathological and imaging features with cyst fluid analysis in a series of patients undergoing surgery for macrocystic serous cystadenoma.

METHODS

Eight patients underwent pancreatic resection for a macrocystic lesion of the pancreas diagnosed on ultrasonography or CT. Endoscopic ultrasonography and preoperative fine-needle aspiration were performed in seven patients. Immunohistochemical analysis of the surgical specimen with antibodies to carcinoembryonic-antigen (CEA), carbohydrate antigen (CA) 19-9, estrogen receptor, and progesterone receptor antibodies was performed in all cases.

RESULTS

Patients included seven women and one man, with a mean age of 48 yr. Lesions were incidentally discovered on ultrasonography in six patients and had a mean size of 3 cm (range, 1.5-5 cm). Endoscopic ultrasonography revealed millimetric cysts in three cases. In the seven aspirated cysts, cytological analysis was non-contributive, but biochemical analysis showed low content of CEA (< 5 ng/ml) and CA72.4 (< 40U/ml) in all but two. At histology, cysts were lined by clear cuboidal cells. They focally expressed CA19-9 but were negative for anti-CEA, antiestrogen receptor, and antiprogesterone receptor antibodies. Microscopic cysts in the wall of the lesions were demonstrated in five cases.

CONCLUSIONS

Macrocystic serous cystadenoma is a particular variant of pancreatic serous cystadenoma. Endoscopic ultrasonography may be useful in detecting peripherally located millimetric cysts in unilocular lesions, and measurement of enzymes and tumor markers in cyst fluid may also contribute to the diagnosis showing low concentrations.

Role of endoscopic ultrasound (EUS) and EUS-guided fine needle aspiration in the diagnosis and treatment of cystic lesions of the pancreas

INTRODUCTION AND AIMS

Cystic neoplasms of the pancreas may be inadvertently treated as benign pseudocysts in clinical practice, often without the use of cytology, cyst tumor markers, or histopathology. We assessed the utility of EUS-guided fine-needle aspiration (EUS-FNA) to assist in the diagnosis and management of pancreatic cysts.

METHODOLOGY

All patients who had pancreatic cysts detected by EUS over a 24-month period were analyzed. Preoperative diagnosis was derived from an algorithm combining clinical history and endosonographic features. In selected cases, EUS-FNA was performed and cyst fluid aspirates were analyzed. Surgical specimens served as diagnostic standard.

RESULTS

A total of 43 patients with pancreatic cysts underwent 45 EUS examinations. Surgical specimens were obtained from 9 patients (mucinous cystadenocarcinoma, 3; adenocarcinoma, 3; pancreatic endocrine tumor, 2; and benign cyst, 1); diagnostic EUS correctly predicted malignant cysts in 8/9 (88.9%). One case inaccurately interpreted by EUS as cystic neoplasm turned out to be a benign cyst on resection. Twenty-one patients underwent EUS-FNA. The cytologic interpretation was adenocarcinoma in 9.5% (2/21); suspicious for malignancy or atypical cells in 19.0% (4/21); benign in 66.6% (14/21); and insufficient cells in 4.8% (1/21).

CONCLUSION

The information gathered from clinical history and EUS, complemented by fluid analysis after EUS-guided FNA, predicts neoplastic pancreatic cysts and assists in decision-making for medical or surgical approach.

Histology of cystic tumors of the pancreas

The cystic tumors of the pancreas constitute a considerable diagnostic challenge because of their overlapping clinical, radiologic, and pathologic features. They may be difficult to differentiate from one another and from benign lesions such as pseudocysts. Because many of the tumors in this group are potentially curable, correct diagnosis is essential for proper patient management. Even when correctly diagnosed, thorough microscopic evaluation is required for the mucin-producing tumors to correctly determine their degree of malignant progression in any given case. Most recently, molecular analysis of these tumors has demonstrated definitively that the serous and mucinous types of cystic neoplasms of the pancreas are unrelated pathogenetically. Conversely, molecular data indicate similarities between the mucinous types of cystic tumors and ductal adenocarcinoma of the pancreas, but the essential molecular differences that underlie the differences in biological behavior are as yet undetermined.

Role of tumor markers in the diagnosis of cystic and intraductal neoplasms

Despite recent advances in imaging procedures, the correct diagnosis of cystic lesions of the pancreas is lacking in about one third of cases. Cyst fluid analysis can help in the differential diagnosis, particularly in patients with unilocular or paucilocular lesions, thus precluding unjustified resection in patients with benign cystic lesions of the pancreas. Although use of cystic fluid marker analysis is helpful in several situations, it is crucial to carefully evaluate the clinical context with appraisal of patient's demographics, clinical symptoms, and morphologic data. A multidisciplinary approach is advised and should improve the overall diagnostic performance and lead to better management strategies in patients presenting with such tumors of the pancreas.

Benign inflammatory pancreatic mucinous cystadenomas mimicking locally advanced cystadenocarcinomas. Presentation of 3 cases

We report 3 cases of benign mucinous cystadenoma of the pancreas mimicking, both clinically and on imaging findings, locally advanced cystadenocarcinoma spreading to neighbouring organs (stomach, splenic and mesenteric vessels, and diaphragm). Surgical resection was performed in light of the suspicion of invasive carcinoma in all 3 cases. Histological examination of the resected specimens showed entirely benign mucinous cystadenomas associated with marked peri-tumoural inflammation that accounted for the pre-operative misdiagnoses. All 3 patients are alive 40, 47 and 54 months after surgery without evidence of tumour relapse. These cases indicate that surgery must be considered in patients with cystic tumour of the pancreas suggesting locally advanced cystadenocarcinoma, even when pre-operative imaging findings suggest tumour extension into neighbouring organs.

Cystic neoplasms of the pancreas

Cystic tumors of the pancreas have become increasingly prevalent. In large series, more than 90% of pancreatic cystic neoplasms are accounted for by mucinous cystadenomas and cystadenocarcinomas, serous cystadenomas, and intraductal papillary mucinous tumors. Differentiating cystic neoplasms from pseudocysts can almost always be accomplished by clinical and radiological means, but in doubtful cases, when observation is contemplated, or when it is important to determine preoperatively the type of cystic neoplasm, cyst fluid analysis is useful. This can be readily obtained by endoscopic ultrasound, and analysis of enzymes, viscosity, cytology and a variety of tumor markers allows for a better differential diagnosis.

Role of endoscopic ultrasound in the diagnosis of cystic lesions of the pancreas

Endoscopic ultrasound (EUS) is an ideal imaging technique for pancreatic cystic lesions. Ultrasound is exquisitely sensitive for detecting and characterizing cysts arising in solid organs, and when the transducer is placed on an endoscope, high resolution imaging of the pancreas is achieved. Linear EUS can also guide needle aspiration of pancreatic cystic lesions and through the use of aspiration cytology, cystic tumors of the pancreas can be diagnosed. Since cytology is a relatively insensitive test, cyst fluid tumor markers such as CEA have been employed to improve the sensitivity for the detection of malignancy. Cyst fluid CEA values are uniformly low in serous cystadenomas, higher in mucinous lesions, and markedly elevated in mucinous cystadenocarcinomas. Through the use of these techniques, the ability to detect and diagnose early malignancies of the pancreas will be greatly enhanced.

Cystic tumors of the pancreas: the radiologist

In this article, the author reviews the effect of contemporary imaging techniques on the diagnosis of various pancreatic neoplasms. Histologic detail and the relationship to other means of diagnosis are included.

Surveillance of pre-malignant disease of the pancreatico-biliary system

Technical advancements in ultrasonography, contrast-enhanced computed tomography and magnetic resonance imaging, as well as the wider availability of these ultramodern imaging techniques, have resulted in the early detection and a better classification of various asymptomatic and symptomatic pancreatico-biliary lesions. Pre-malignant biliary and pancreatic lesions are rare disorders, and no clear data are available to define their malignant potential. Because of the lack of controlled epidemiological data, the time span for malignant transformation and its frequency cannot be defined in the majority of these lesions. Adenomyomatosis of the gallbladder and gallbladder polyps larger than 10 mm should be treated by cholecystectomy even in asymptomatic patients because of an increased risk of malignant transformation. Chronic cholangitis, primary sclerosing cholangitis and choledochal cysts are also pre-malignant conditions. The timing of surgery, once it is advised for a pre-malignant condition that is still benign, should, however, be individualized to the particular patient situation. In patients with chronic pancreatitis, surgery may be indicated for disease-related complications. In as much as chronic pancreatitis predisposes to a higher risk of pancreatic cancer, any suspicion of malignancy should warrant a surgical exploration. Intraductal papillary tumours and mucin-producing pancreatic tumours are other pre-malignant pancreatic lesions whose malignant potential cannot be precisely determined pre-operatively. They should be resected in situations where there is a high degree of suspicion even without a clear objective diagnosis. In conclusion, pre-malignant hepato-biliary and pancreatic lesions of uncertain pathology should undergo early resection in view of treatment limitations and the dismal prognosis of established cancers. While hepato-biliary and pancreatic surgery is nowadays performed in specialized centres, with a low post-operative morbidity and mortality, it is equally important to understand that observation alone with regular computed tomography or magnetic resonance imaging control can no longer be recommended in the management of these lesions.

Cystic Neoplasms of the Pancreas

Pancreatic cystic neoplasms are uncommon, but are being detected at an increased rate in the current era of sophisticated abdominal imaging. The selection of appropriate treatment depends on the ability to distinguish benign from malignant cysts. The most common clinical mistake is to treat a cystic neoplasm as a benign pseudocyst. The identification of a cyst as a cystic neoplasm should be suspected on clinical grounds, but the differentiation from a benign cyst is often difficult based on clinical features and imaging alone. Analysis of cystic fluid for tumor markers and cytology should be considered, using newer approaches such as endoscopic ultrasound-guided fine needle aspiration (FNA), in those patients in whom this information may guide appropriate therapy. Surgical excision of a cystic pancreatic neoplasm is the treatment of choice in patients fit for surgery. Inappropriate treatment of these lesions as pseudocysts, by radiographic, endoscopic, or surgical drainage, is to be avoided. Resection of the lesion should be seriously considered even in the absence of symptoms, as these lesions have malignant potential and are often curable.

Simultaneous mucinous cystadenoma of ovary and mucinous cystadenocarcinoma of pancreas

Mucinous cystic tumors were discovered synchronously in the tail of the pancreas and in the right ovary of an adult female. Both tumors were amenable to surgical resection. The pancreatic tumor was a noninvasive mucinous cystadenocarcinoma and the ovarian tumor was a mucinous cystadenoma. We feel these tumors represent two primaries, an uncommon occurrence, and not a single primary tumor with metastasis.

Macrocystic serous cystadenoma of the pancreas: clinicopathologic features in seven cases

BACKGROUND

Serous cystic neoplasms of the pancreas are uncommon tumors classified as microcystic adenomas. In this article, the authors report clinico-pathologic features of seven cases of macrocystic variant of the serous cystadenoma.

METHODS

Seven patients (5 females and 2 males) with a diagnosis of cystic lesion of the pancreas were observed after 1995. Clinical, radiological, and pathologic features, including immunohistochemistry, were reported. Enzymes and tumor markers CEA, CA 19-9, CA 125, CA 15-3, CA 72-4, and mucin-like carcinoma-associated antigen (MCA) were investigated in the serum and cyst fluid of the patients. Cytology was also performed.

RESULTS

Six patients were symptomatic complaining abdominal pain. All cases had radiologic evidence of unilocular cyst of the pancreas. The suspected diagnosis was consistent with mucinous cystic neoplasm. Serum tumor markers were all in the normal range. After surgery, pathology showed in all cases a cyst lined with cuboidal, periodic acid-Schiff (PAS)-positive epithelium, without mucin content or atypia. Minute microcysts were found surrounding the main cavity. Immunohistochemical stains were positive for cytokeratin, CA19-9, CA15-3, CA 72-4, and MCA. CEA was unexpressed. CA 125 in the cyst fluid were found elevated in three cases and CA 19-9 in three cases. Cytology was negative in all cases.

CONCLUSION

When a unilocular pancreatic cyst is found, without history of pancreatitis and gallstones, having low serum tumor markers levels and negativity of CA 72-4 and MCA in the cyst fluid, the diagnosis of the macrocystic variant of the serous cystadenoma may be suggested. At present, the diagnosis is still based on pathological examination after cyst removal.

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.

Telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts

BACKGROUND

Pancreatic serous cystadenoma, mucinous cystic neoplasms, ductal adenocarcinoma with cystic change, and pseudocysts are a spectrum of pancreatic cystic lesions. Their management strategy and prognosis are extremely diverse. Imaging study, cytology, and analysis of the tumor markers of cyst fluid are not always reliable in differentiation of these disease entities.

MATERIALS AND METHODS

Fifteen patients with pancreatic cystic neoplasms (including six mucinous cystadenocarcinomas, two mucinous cystic neoplasms with borderline malignancy, two mucinous cystadenomas, and five serous cystadenomas), 4 patients with pancreatic ductal adenocarcinomas with cystic change, and 10 patients with pseudocysts were studied. Echo-guided or computed tomography-guided biopsies of pancreatic cystic lesions and their normal counterparts were conducted on all patients prior to operation or other management. The specimens were assayed for telomerase activity by using TRAP (telomere repeat amplification protocol). The level of telomerase activity in each specimen was semiquantitated as strong, moderate, weak, and none. The final diagnoses were made from histopathological examination of surgically resected or biopsied specimens. The efficacy of telomerase activity as a tumor marker to predict malignancy of pancreatic cystic lesions was evaluated.

RESULTS

Three of the four pancreatic ductal adenocarcinomas with cystic change had strong or moderate telomerase activity; four of the six mucinous cystadenocarcinomas had moderate or weak telomerase activity; one of the two mucinous cystadenomas with borderline malignancy had weak telomerase activity; and none of their normal counterparts had detectable telomerase activity. In contrast, none of the two mucinous cystadenomas, five serous cystadenomas, and 10 pseudocysts had detectable telomerase activity. Based on these results, the sensitivity of telomerase activity for prediction of malignancy or premalignancy of pancreatic cystic lesions was 67%, the specificity was 100%, and the positive and negative predictive values were 1.0 and 0.81, respectively. The overall accuracy was 86%.

CONCLUSIONS

The differential expressions of telomerase activity have been detected specifically in malignant and premalignant pancreatic cystic tumors, but not in benign cystic neoplasms or pseudocysts. The implications of these results are that telomerase activation takes part in the malignant transformation of pancreatic cystic neoplasms and that telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.

Large cystic pancreatic neoplasms: pathology, resectability, and outcome

BACKGROUND

Cystic pancreatic neoplasms may be benign, premalignant, or malignant. These lesions may remain asymptomatic for long periods and can be quite large at the time of presentation.

METHODS

A retrospective analysis was used to determine whether preoperative evaluation can predict pathology and determine resectability and outcome.

RESULTS

Over 12 years, 145 cystic pancreatic neoplasms, of which 24 (17%) were larger than 10 cm, were managed at the Johns Hopkins Hospital. Those 24 large tumors included 9 of 73 cystadenomas (12%), 7 of 27 cystadenocarcinomas (26%), 2 of 35 adenocarcinomas producing mucin or associated with a cyst (6%), 5 of 9 Hamoudi tumors (55%), and 1 dermoid cyst. Clinical symptoms, liver function tests, and computed tomographic scans did not distinguish benign from malignant pathology. On 18 angiograms, 2 malignant and 4 benign neoplasms demonstrated encasement or occlusion; however, 3 of these 6 tumors were resectable. Twenty of 22 patients (91%) who were explored underwent resection with no hospital mortality. For the entire series, 5-year survival for those with cystadenomas, cystadenocarcinomas, and cystic adenocarcinomas was 97%, 38%, and 9%, respectively. Three-year survival for those 7 with cystadenocarcinomas larger than 10 cm was 54%, compared with 51% for those 20 with smaller cystadenocarcinomas.

CONCLUSIONS

Preoperative evaluation usually does not predict pathology, resectability, or outcome. Moreover, resectability is high and morbidity is low, irrespective of size. Large cystic pancreatic tumors should be explored to determine pathology, attempt resection, and provide an opportunity for long-term survival.

Nonoperative management of pancreatic pseudocysts. Problems in differential diagnosis

CONCLUSION

The evaluation of pancreatic cystic lesions entails a misdiagnosis risk. Awareness of the problem, knowledge of the natural history of these lesions, and meticulous posttreatment follow-up can reduce the consequences of diagnostic errors. If all these precautions are adopted, pancreatic pseudocysts can be safely treated nonoperatively.

BACKGROUND

The accurate diagnosis of pancreatic cystic lesions remains a problem. The aim of this study was to ascertain the incidence of and the reasons the diagnostic errors occurred in a series of pseudocysts drained percutaneously and to compare these data to those reported in the literature.

METHODS

Data from 70 patients bearing one or more pseudocysts who underwent a percutaneous drainage were reviewed. The pretreatment workup included medical history, physical examination, ultrasound (US) and computed tomography (CT) scans, amylase assay in both the serum and the cystic fluid, culture and cytology of the cystic fluid. After removal of the drainage, the minimum follow-up period was 12 mo.

RESULTS

Four patients died, and two cancer-associated pseudocysts were identified before removal of the drainage. Sixty-four patients were followed up for a mean of 51.9 mo (range 12-154 mo). A third cancer and a mucinous cystic tumor, fully communicating with the main duct, were further detected during this period.

Mucinous cystic neoplasm (mucinous cystadenocarcinoma of low-grade malignant potential) of the pancreas: a clinicopathologic study of 130 cases

Mucinous cystic neoplasms (MCNs) of the pancreas are uncommon tumors. The classification and biologic potential of these neoplasms remain the subject of controversy. Attempts to classify these tumors in a similar manner to ovarian MCNs remains controversial, as even histologically benign-appearing pancreatic MCNs metastasize and are lethal. One hundred thirty cases of MCNs were identified in the files of the Endocrine Pathology Tumor Registry of the Armed Forces Institute of Pathology from the years 1979 to 1993. The pathologic features, including hematoxylin and eosin staining, histochemistry, immunohistochemistry (IHC), cell cycle analysis, and K-ras oncogene determination were reviewed. These findings were correlated with the clinical follow-up obtained in all cases. There were 130 women, aged 20-95 years (mean age at the outset, 44.6 years). The patients had vague abdominal pain, fullness, or abdominal masses. More than 95% of the tumors were in the pancreatic tail or body and were predominantly multilocular. The tumors ranged in size from 1.5 to 36 cm in greatest dimension, with the average tumor measuring >10 cm. A spectrum of histomorphologic changes were present within the same case and from case to case. A single layer of bland-appearing, sialomucin-producing columnar epithelium lining the cyst wall would abruptly change to a complex papillary architecture, with and without cytologic atypia, and with and without stromal invasion. Ovarian-type stroma was a characteristic and requisite feature. Focal sclerotic hyalinization of the stroma was noted. This ovarian-type stroma reacted with vimentin, smooth muscle actin, progesterone, or estrogen receptors by IHC analysis. There was no specific or unique epithelial IHC. K-ras mutations by sequence analysis were wild type in all 52 cases tested. Ninety percent of patients were alive or had died without evidence of disease (average follow-up 9.5 years), irrespective of histologic appearance; 3.8% were alive with recurrent disease (average 10 years after diagnosis); and 6.2% died of disseminated disease (average 2.5 years from diagnosis). Irrespective of the histologic appearance of the epithelial component, with or without stromal invasion, pancreatic MCNs should all be considered as mucinous cystadenocarcinomas of low-grade malignant potential. Pancreatic MCNs cannot be reliably or reproducibly separated into benign, borderline, or malignant categories.

Measurement of pS2 protein in pancreatic cyst fluids. Evidence for a potential role of pS2 protein in the pathogenesis of mucinous cystic tumors

CONCLUSION

Elevated levels of the growth factor pS2 protein in the cyst fluids of mucinous cystic tumors correlate with earlier observations using immunohistochemical techniques showing that pS2 protein is expressed by these tumors. The markedly elevated levels of pS2 protein compared to normal plasma values suggest that this growth factor may be important in the pathogenesis of pancreatic mucinous cystic tumors.

BACKGROUND

Cystic lesions of the pancreas include inflammatory pseudocysts, serous cystadenomas, and mucinous cystic tumors, some of which are malignant. Previous studies using immunohistochemical techniques have shown that virtually all pancreatic mucinous tumors express pS2 protein. pS2 protein is a growth factor that is believed to be important in the normal process of inflammation and repair. We measured pS2 protein and other growth factors in pancreatic cyst fluids to assess their potential pathophysiologic and diagnostic significance.

METHODS

Levels of pS2 protein were measured in 54 pancreatic cyst fluids by radioimmunoassay. The growth factors, epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha), and insulin-like growth factors I and II (IGF-I, IGF-II) were measured in 22 cyst fluids using commercial immunoassays.

RESULTS

Mucinous cysts exhibited significantly higher levels of cyst fluid pS2 protein than nonmucinous lesions, including pseudocysts and serous cystadenomas (median: 78,303 pg/mL; range: 218-361,176 pg/mL vs median: 886 pg/mL; range: 0-14,206 pg/mL; p = 0.0001). The level of pS2 in mucinous tumors was markedly higher than plasma values (median: 392 pg/mL). Levels of pS2 protein in malignant mucinous lesions tended to be higher than those in benign mucinous cysts, but this difference was not statistically significant (median: 88,817 vs 64,350 pg/mL; p = 0.159). Levels of other growth factors, including EGF, TGF-alpha, IGF-I, and IGF-II, did not discriminate among the different cyst types, and the values were within normal plasma ranges.

Cystic tumours of the pancreas

BACKGROUND

Cystic pancreatic tumours may be misdiagnosed as pseudocysts.

METHODS

From August 1990 to January 1998, 21 patients (16 women) with a median age of 60 years underwent operation for a cystic mass in the pancreas with histological confirmation of neoplasia (six serous cystadenoma (SCA), three mucinous cystic adenoma (MCA), ten mucinous cystadenocarcinoma (MCAC), one ductal adenocarcinoma with cystic degeneration, one cystic islet cell tumour).

RESULTS

While the lesion had been labelled as a pseudocyst in eight patients, only one patient (MCA in the pancreatic head) had had acute pancreatitis previously. In seven patients the computed tomogram (CT) lacked suspicious neoplastic features, while endoscopic retrograde cholangiopancreatography, angiography and percutaneous cyst fluid analysis were unhelpful or misleading in 16 of 18 investigations with respect to differentiating tumour from pseudocyst. Attempted operation for cure was performed in 18 patients despite diagnostic delays of up to 6 years and initial treatment with cystenterostomy in two cases.

CONCLUSION

Retrospective review revealed that all 21 cystic neoplasms could be diagnosed before operation by a history excluding previous pancreatitis (20 of 21 patients) or a CT suspicious for neoplasia (14 of 21). The diagnosis relies more on absence of previous pancreatitis and a suspicious clinician who errs on the side of resecting a pseudocyst rather than watching or draining a cystic neoplasm.

K-ras oncogene mutations indicate malignancy in cystic tumors of the pancreas

OBJECTIVE

To evaluate clinical parameters, presurgical diagnostic tests, histologic findings, and the presence of K-ras oncogene mutations in cystic tumors of the pancreas to determine which best predict malignancy.

SUMMARY BACKGROUND DATA

Because presurgical, intraoperative, and final pathologic differentiation is difficult in cystic tumors of the pancreas, it would be a major benefit to identify markers that accurately predict malignancy in these rare tumors. The role of K-ras oncogene mutations as an indicator of malignancy has not been determined in these tumors.

METHODS

Nineteen patients with cystic tumors of the pancreas were evaluated, including K-ras mutation analysis based on polymerase chain reaction and restriction digestion assays and direct DNA sequencing, to screen for parameters that accurately predict malignancy.

RESULTS

All malignant cystic pancreatic tumors (five cystadenocarcinomas and three mucin-producing adenocarcinomas) harbored K-ras mutations at codon 12 or 13. K-ras mutations were also detected in the percutaneous fine-needle aspirates of two of these patients. In contrast, none of nine benign cystadenomas or the solid-papillary neoplasm had K-ras mutations. None of the patients with a benign tumor carrying K-ras wild-type sequences developed recurrent disease after a mean follow-up of 50 months. Seven of the 8 malignant cystic pancreatic tumors, but none of the 11 benign tumors, showed dilatation of the main pancreatic duct on computed tomography or endoscopic retrograde cholangiopancreatography.

CONCLUSIONS

K-ras mutation analysis seems to be a powerful tool to determine the malignant potential of cystic pancreatic tumors before and after surgery. Dilatation of the main pancreatic duct on computed tomography or endoscopic retrograde cholangiopancreatography is highly suggestive for malignancy in these rare tumors.

Serum tumor markers and cyst fluid analysis are useful for the diagnosis of pancreatic cystic tumors

BACKGROUND

This study was performed to evaluate the utility of serum and cyst fluid analysis for enzymes (amylase and lipase) and tumor markers (carcinoembryonic antigen, CA 19-9, CA 125, and CA 72-4) in the differential diagnosis of cystic pancreatic lesions.

METHODS

Serum and cyst fluid were obtained from 48 patients with pancreatic cysts (21 pseudocysts, 14 mucinous cystic neoplasms, 6 ductal carcinomas, and 7 serous cystadenomas), observed between 1989 and 1994.

RESULTS

Serum CA 19-9 levels were significantly higher in ductal carcinomas (all > 100 U/mL) and mucinous cystic neoplasms (P < 0.05). CA 72-4 cyst fluid levels were significantly higher in mucinous cystic tumors (P < 0.005), with 95% specificity and 80% sensitivity in detecting mucinous or malignant cysts. A combined assay of serum CA 19-9 and cyst fluid CA 72-4 correctly identified 19 of 20 (pre-) malignant lesions (95%), with only 1 false-positive result (3.6%). Cytology showed a sensitivity of 48% and specificity of 100%.

CONCLUSIONS

Any pancreatic cyst with high serum CA 19-9 values, positive cytology, or high CA 72-4 in the fluid should be considered for resection.