Pathological features related to onco-immunity and their clinical significance of pancreatic ductal adenocarcinoma / 中华病理学杂志

Objective: To investigate the tumor immunity-related pathologic features and clinical significance in pancreatic ductal adenocarcinoma (PDAC). Methods: All pathologic materials and clinical information of 192 PDAC patients from the Cancer Hospital of the University of Chinese Academy of Sciences from January 2010 to December 2020 were collected. The onco-immune microenvironment associated morphologic features were evaluated, and MHC-Ⅰ, PD-L1, CD3, and CD8 expression were detected by immunohistochemistry (IHC). Then the correlation between the factors and their influence on prognosis was analyzed. Results: There were 163 cases of non-specific adenocarcinoma (163/192, 84.90%), 18 cases of adeno-squamous carcinoma (18/192, 9.37%), and 11 cases of other rare subtypes (11/192, 5.73%). Perineural invasion was observed in 110 cases (110/192, 57.29%) and vascular invasion in 86 cases (86/192, 44.79%). There were 84 cases (84/182, 46.15%) with severe chronic inflammation. Tumor infiltrating immune cell numbers (TII-N) were increased in 52 cases (52/192, 27.08%). Lymphocytes and plasma cells were the main infiltrating immune cells in 60 cases (60/192, 31.25%), whereas in 34 cases (34/192, 17.71%) the tumors were mainly infiltrated by granulocytes, and 98 cases (98/192, 51.04%) showed mixed infiltration. CD3+T cells were deficient in 124 cases (124/192, 66.31%). CD8+T cells were deficient in 152 cases (152/192, 79.58%). MHC-Ⅰ expression was down-regulated in 156 cases (156/192, 81.25%), and PD-L1 was positive (CPS≥1) in 46 cases (46/192, 23.96%). Statistical analysis showed that TII-N was negatively correlated with vascular invasion (P=0.035), perineural invasion (P=0.002), stage (P=0.004) and long-term alcohol consumption (P=0.039). The type of immune cells correlated positively with chronic pancreatic inflammation (P=0.002), and negatively with tumor differentiation (P=0.024). CD8+T cells were positively correlated with CD3+T cells (P=0.032), MHC-Ⅰ expression (P<0.001) and PD-L1 expression (P=0.001), and negatively correlated with long-term smoking (P=0.016). Univariate analysis showed that histological nonspecific type (P=0.013) and TII-N (P<0.001) were the factors for good prognosis. Vascular invasion (P=0.032), perineural invasion (P=0.001), high stage (P=0.003) and long-term alcohol consumption (P=0.004) were adverse prognostic factors. COX multivariate risk analysis found that TII-N was an independent favorable factor for PDAC, while perineural invasion was an independent adverse risk factor. Conclusions: TII-N is an independent superior prognostic factor for PDAC, and significantly correlated with many factors; chronic alcohol consumption and smoking may inhibit onco-immunity in PDAC patients.

A pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) (NET and undifferentiated carcinoma of the pancreas with osteoclast-like giant cells) with metastatic neuroendocrine component to the liver

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UCOGCs) is an extremely rare morphologically and clinically distinct variant of pancreatic ductal adenocarcinoma (PDAC), exhibiting a characteristic component of reactive osteoclast-like giant cells admixed with neoplastic mononuclear cells. Sommers and Meissner first described it in 1954 as an "unusual carcinoma of the pancreas". Later it acquired many different names. In 2010, the WHO classified these tumors as a variant of PDAC under the heading of "undifferentiated carcinoma with osteoclast-like giant cells". Here we describe the first case of pancreatic mixed neuroendocrine-non-neuroendocrine neoplasms (MiNEN) composed of UCOGC and pancreatic neuroendocrine tumor (NET), which occurred in a 78-year-old man with biliary colic and pancreatitis. The mass did not respond to the chemotherapy, and he soon developed liver metastasis from the NET component, and unfortunately, the patient passed away 10 months later. Since UCOGC is extremely rare, and its association with NET has not been reported yet, our case expands the knowledge regarding its unusual presentation and poor prognosis.

CCAT2 is an oncogenic long non-coding RNA in pancreatic ductal adenocarcinoma

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is highly aggressive with poor prognosis. Long non-coding RNAs (lncRNAs), a group of non-coding RNAs, play important roles in the progression of PDAC. This study aimed to investigate the potential involvement of lncRNA CCAT2 in PDAC tumorigenesis. Methods Expression of CCAT2 was detected by quantitative real-time PCR (qRT-PCR) in 80 human PDAC tissues and three PDAC cell lines. The effects of CCAT2 silencing in PANC-1 cells on cell proliferation and invasion were studied using MTT assay and transwell assay, respectively. The effect of CCAT2 silencing on tumorigenesis was assessed by PANC-1 xenograft in vivo. Using si-KRAS, the role of KRAS to regulate CCAT2 was evaluated by qRT-PCR and luciferase reporter assay. The involvement of MEK/ERK and PI3K/AKT signaling in CCAT2 regulation was investigated by pathway inhibitors PD98059 and LY294002, respectively. Results CCAT2 was significantly elevated in high-grade PDAC tissues and higher CCAT2 expression was correlated with lower survival rate in PDAC patients. CCAT2 was up-regulated in PDAC cell lines, as compared with normal pancreatic cells. Silencing of CCAT2 inhibited cell proliferation and invasion in PANC-1 cells in vitro, and attenuated tumorigenesis of PANC-1 xenograft in vivo. Furthermore, CCAT2 was regulated by KRAS through MEK/ERK signaling pathway. Conclusions CCAT2 is an oncogenic lncRNA in PDAC likely regulated by the KRAS-MEK/ERK pathway. It could be a potential diagnostic biomarker and therapeutic target for PDAC.

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells reported in an asymptomatic patient: a rare case and literature review

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UC-OGC) is a rare and poorly described pancreatic malignancy. It is comprised of mononuclear, pleomorphic, and undifferentiated cells as well as osteoclast-like giant cells (OGC's). It constitutes less than 1% of pancreatic non-endocrine neoplasia and is twice as likely to occur in females as in males. Its histopathologic properties remain poorly understood. It is suspected that UC-OGC is of epithelial origin that can then transition to mesenchymal elements. As part of this study, we describe a case of a malignant pancreatic neoplasm that was discovered in a 69-year old patient as an incidental finding. We also provide an overview of previously published data to highlight UC-OGC's clinical and pathologic features.

Evaluation of microvessel density and p53 expression in pancreatic adenocarcinoma

OBJECTIVE: To evaluate the prognostic significance of microvessel density and p53 expression in pancreatic cancer. METHODS: Between 2008 and 2012, 49 patients with pancreatic adenocarcinoma underwent resection with curative intention. The resected specimens were immunohistochemically stained with anti-p53 and anti-CD34 antibodies. Microvessel density was assessed by counting vessels within ten areas of each tumoral section a highpower microscope. RESULTS: The microvessel density ranged from 21.2 to 54.2 vessels/mm2. Positive nuclear staining for p53 was found in 20 patients (40.6%). The overall median survival rate after resection was 24.1 months and there were no differences in survival rates related to microvessel density or p53 positivity. Microvessel density was associated with tumor diameter greater than 3.0 cm and with R0 resection failure. CONCLUSIONS: Microvessel density was associated with R1 resection and with larger tumors. p53 expression was not correlated with intratumoral microvessel density in pancreatic adenocarcinoma.

Synchronous Pancreatic Ductal Adenocarcinomas Diagnosed by Endoscopic Ultrasound-Guided Fine Needle Biopsy

Cases of pancreatic ductal adenocarcinoma with multiple masses accompanying underlying pancreatic diseases, such as intraductal papillary mucinous neoplasm, have been reported. However, synchronous invasion without underlying pancreatic disease is very rare. A 61-year-old female with abdominal discomfort and jaundice was admitted to our hospital. Abdominal computed tomography (CT) revealed cancer of the pancreatic head with direct invasion of the duodenal loop and common bile duct. However, positron emission tomography-CT showed an increased standardized uptake value (SUV) in the pancreatic head and tail. We performed endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) for the histopathologic diagnosis of the pancreatic head and the evaluation of the increased SUV in the tail portion of the pancreas, as the characteristics of these lesions could affect the extent of surgery. As a result, pancreatic ductal adenocarcinomas were confirmed by both cytologic and histologic analyses. In addition, immunohistochemical analysis of the biopsy specimens was positive for carcinoembryonic antigen and p53 in both masses. The two masses were ultimately diagnosed as pancreatic ductal adenocarcinoma, stage IIB, based on EUS-FNB and imaging studies. In conclusion, the entire pancreas must be evaluated in a patient with a pancreatic mass to detect the rare but possible presence of synchronous pancreatic ductal adenocarcinoma. Additionally, EUS-FNB can provide pathologic confirmation in a single procedure.

Análise da expressão de RNAs não codificadores longos em adenocarcinoma de pâncreas / Expression analysis of long noncoding RNAs in pancreatic adecarcinoma

RNAs não codificadores longos (lncRNAs) compõem uma fração significativa do transcriptoma. Alterações na expressão de lncRNAs já foram observadas em vários cânceres humanos, mas ainda não foram exploradas no adenocarcinoma pancreático ductal (PDAC), uma doença devastadora e agressiva para a qual faltam métodos para diagnóstico precoce e tratamentos efetivos. Utilizando uma plataforma de microarranjo de cDNA com sondas para 984 lncRNAs e 2371 mRNAs, o presente estudo identificou conjuntos de lncRNAs expressos em 38 amostras clínicas pancreáticas. O enriquecimento de (i) elementos regulatórios associados às regiões promotoras (H3K4me3); (ii) possíveis inícios de transcrição (CAGE-tags); (iii) presença de elementos conservados sugere que ao menos uma fração desses RNAs seja originada a partir de unidades transcricionais independentes, reguladas e possivelmente funcionais. Foram identificadas assinaturas de expressão gênica compostas por mRNA e lncRNAs associadas ao tumor primário e à metástase pancreática. A assinatura gIenica associada à metástase apresentou enriquecimento RNAs intrônicos de loci gênicos associados à via MAPK quinase. O aumento de expressão dos transcritos intrônicos dos loci PPP3CB, MAP3K14 e DAPK1 foi confirmado por qPCR em metástases. Em conjunto, este trabalho aponta para a importância de lncRNAs intrônicos no PDAC e para a necessidade de estudos mais aprofundados para uma melhor compreensão do papel dessa classe de transcritos na biologia da doença

Long noncoding RNAs (lncRNAs) compose a significant fraction of transcriptome. Altered expression of lncRNAs has been observed in diverse human cancers, but has not being investigated in pancreatic ductal adenocarcinoma (PDAC), a devastating and aggressive disease that lack early diagnosis methods and effective treatments. Using a cDNA microarray platform with probes interrogating 984 lncRNAs and 2371 mRNA, the present study identified subsets of lncRNAs expressed in 38 pancreatic clinical samples. Enrichment of (i) regulatory elements associated to promoter region (H3K4me3); (ii) putative transcription start site (CAGEtags) and (iii) conserved elements, suggest that at least a fraction of these RNAs could be independent transcriptional unit, regulated, an possibly functional. Gene expression signatures comprised of mRNAs and lncRNAs and associated to primary or metastatic tumors were found. A gene signature associated to metastasis was enriched in intronic ncRNAs mapping to gene loci associated to the MAPK pathway. Over expression of intronic RNAs from PPP3CB, MAP3K14 and DAPK1 was confirmed by qPCR in metastatic samples. Taken together, this study points to the importance of intronic lncRNAs in PDAC and for the need to study this class of ncRNAs in greater detail to better understand its role in the biology of PDAC

Comparison of Efficacy of Enucleation and Pancreaticoduodenectomy for Small (<3 cm) Branch Duct Type Intraductal Papillary Mucinous Neoplasm Located at the Head of Pancreas and the Uncinate Process

PURPOSE: Accurate indications and the extent of surgery for branch duct intraductal papillary mucinous neoplasm (IPMN) of the pancreas are still debatable. In particular, small tumor is located at the head portion of pancreas presents a dilemma. The purpose of this study is to compare the efficacy of enucleation (EN) with that of pancreaticoduodenectomy (PD) in patients with small (2 cm

Resultados actuales de la pancreatoduodenectomía para el tratamiento de los tumores periampulares y análisis de factores pronósticos de sobrevida / Results of pancreaticoduodenectomy in the treatment of periampullary tumors

Background: The diagnosis and treatment of periampullary tumors represents a challenge for current medicine. Aim: To review the results of pancreaticoduodenectomy (PDD) in the treatment of periampullary tumors and to identify risk factors that impact the long-term survival. Patients and Methods: We performed a retrospective study of patients who underwent a PDD for periampullary tumors between 1993 and 2009. We reviewed perioperative results and long term survival. We performed a multivariate analysis for long-term survival. Results: A PDD was performed in 181 patients aged 58 ± 12 years (98 females). Piloric preservation was done in 53 percent and a pancreatogastric anastomosis was used in 94 percent of cases. Morbidity was 62 percent and postoperative mortality was 5.5 percent. Pancreatic cancer was the most frequent pathological finding in 41 percent, followed by ampullary cancer in 28 percent and distal bile duct cancer in 16 percent. Median survival was 17 months, with a five years survival of 24 percent. Survival for ampullary tumors was 28 months with a five years survival of 32 percent. The median and five years survival were 14 months and 16 percent for bile duct cancer and 11 months and 14 percent for pancreatic cancer. Multivariate analysis identified tumor type (pancreas /bile duct) and lymph node dissemination as independent predictors of mortality. Conclusions: One quarter of patients experienced long term survival. Mortality predictors were tumor type and lymph node dissemination.

Determination of Malignant and Invasive Predictors in Branch Duct Type Intraductal Papillary Mucinous Neoplasms of the Pancreas: A Suggested Scoring Formula

Prediction of malignancy or invasiveness of branch duct type intraductal papillary mucinous neoplasm (Br-IPMN) is difficult, and proper treatment strategy has not been well established. The authors investigated the characteristics of Br-IPMN and explored its malignancy or invasiveness predicting factors to suggest a scoring formula for predicting pathologic results. From 1994 to 2008, 237 patients who were diagnosed as Br-IPMN at 11 tertiary referral centers in Korea were retrospectively reviewed. The patients' mean age was 63.1 +/- 9.2 yr. One hundred ninty-eight (83.5%) patients had nonmalignant IPMN (81 adenoma, 117 borderline atypia), and 39 (16.5%) had malignant IPMN (13 carcinoma in situ, 26 invasive carcinoma). Cyst size and mural nodule were malignancy determining factors by multivariate analysis. Elevated CEA, cyst size and mural nodule were factors determining invasiveness by multivariate analysis. Using the regression coefficient for significant predictors on multivariate analysis, we constructed a malignancy-predicting scoring formula: 22.4 (mural nodule [0 or 1]) + 0.5 (cyst size [mm]). In invasive IPMN, the formula was expressed as invasiveness-predicting score = 36.6 (mural nodule [0 or 1]) + 32.2 (elevated serum CEA [0 or 1]) + 0.6 (cyst size [mm]). Here we present a scoring formula for prediction of malignancy or invasiveness of Br-IPMN which can be used to determine a proper treatment strategy.

Neoplasia mucinosa intraductal del páncreas: [revisión] / Intraductal papillary mucinous neoplasm of the pancreas: [review]

Intraductal papillary mucinous neoplasm of the pancreas is characterized by a dilatation of the main pancreatic duct and/or secondary ducts, mucin production and the absence of ovarian ¡ike struma. The symptoms are non-specific and often the diagnosis is incidental. The treatment of choice is surgery, since these tumors may become malignant. The prognosis depends on the type of lesion, whether the excision is complete and lymph node involvement. The aim of this review is to analyze the clinical, diganostic, therapeutic and pathological characteristics of this disease.

Pancreatic intraepithelial neoplasia and ductal adenocarcinoma induced by DMBA in mice: effects of alcohol and caffeine

PURPOSE: To evaluate the effects of alcohol and caffeine in a pancreatic carcinogenesis mouse model induced by 7,12-dimethylbenzantracene (DMBA), according to the PanIN classification system. METHODS: 120 male, Mus musculus, CF-1 mice were divided into four groups. Animals received either water or caffeine or alcohol or alcohol + caffeine in their drinking water. In all animals, 1 mg of DMBA was implanted into the head of the pancreas. After 30 days, euthanasia was performed; excised pancreata were then fixed in formalin, stained with hematoxylin-eosin and categorized as follows: normal ducts, reactive hyperplasia, PanIN-1A, PanIN-1B, PanIN-2, PanIN-3 or adenocarcinoma. RESULTS: PanIN lesions were verified in all groups. Adenocarcinoma was detected in 15 percent of animals in the caffeine group, 16.6 percent in the water group, 23.8 percent in the alcohol + caffeine group and 52.9 percent in the alcohol group (P<0.05). CONCLUSIONS: The experimental pancreatic carcinogenesis mouse model using DMBA effectively induces PanIN lesions and pancreatic adenocarcinoma. This study verified the association between alcohol use and pancreatic adenocarcinoma; caffeine did not present the same effect.

OBJETIVO: Avaliar os efeitos do álcool e da cafeína na carcinogênese pancreática induzida pelo 7,12-dimetilbenzantraceno (DMBA) em camundongos, descrevendo as lesões de acordo com a classificação das neoplasias pacreáticas intraepiteliais (PanIN). MÉTODOS: 120 camundogos machos, Mus musculus, CF-1 foram divididos em quatro grupos. Animais receberam água ou cafeína ou álcool ou álcool + cafeína para beber. Em todos animais, 1 mg de DMBA foi implantado na cabeça do pâncreas. Após 30 dias, eutanásia foi realizada, o pâncreas foi removido, fixado em formalina e corado com hematoxilina e eosina sendo classificado em: ductos normais, hiperplasia reativa, PanIN-1A, PanIN-1B, PanIN-2, PanIN-3 ou adenocarcinoma. RESULTADOS: Neoplasias pancreáticas intraepiteliais foram encontradas em todos grupos. Adenocarcinoma foi detectado em 15 por cento dos animais do grupo cafeína, 16,6 por cento do grupo água, 23,8 por cento do grupo álcool + cafeína e 52,9 por cento do grupo álcool (P<0,05). CONCLUSÕES: O modelo experimental de carcinogênese pancreática em camundongos utilizando DMBA induz neoplasias pancreáticas intraepiteliais (PanIN) e adenocarcinoma pancreático. Este estudoverificou associação entre álcool e adenocarcinoma pancreático, enquanto a cafeína não demonstrou este efeito.

Clinicopathological Aspects of 542 Cases of Pancreatic Cancer: a Special Emphasis on Small Pancreatic Cancer

Small pancreatic cancers (longest diameter < or =2 cm) have been regarded as preliminary to early pancreatic cancer, which was thought to be highly curable. During our experience since 1989, we evaluated 542 cases of pancreatic cancer. Among them we found 74 cases of tumors < or =2 cm in diameter, small pancreatic cancer (TS1 pancreatic cancer). Well-differentiated adenocarcinomas (18.9%) and absence of symptoms (8.1%) were more frequent in patients with TS1 than in those with larger pancreatic tumors. Only 16 of the 74 patients (21.6%) with small pancreatic cancers had T1 tumors. According to the International Union Against Cancer (UICC) staging, only 11 patients (14.9%) were stage IA: their 5-yr survival rate was 23.3% and their median survival was 30.0 months. Among these 11 patients, 3 had tumors <1 cm; their median survival time was 30.0 months and their 5-yr survival rate was 50.0%. These findings may indicate that 'small' pancreatic cancer is not equivalent to 'early' pancreatic cancer.

Natural History of Branch-Duct Type Intraductal Papillary Mucinous Neoplasms of the Pancreas / 대한소화기학회지

BACKGROUND/AIMS: Intraductal papillary mucinous neoplasms of the pancreas (IPMNs) are consisted of two types; branch-duct type and main-duct type. Branch-duct type is more common and follows a better course than main-duct type. However, the natural history of branch-duct type IPMN has not been exactly verified yet. The aim of this study was to investigate the natural course of branch-duct type IPMN. METHODS: The medical records of 45 patients with branch-duct type IPMN diagnosed by pancreatogram were reviewed retrospectively. The mean age was 62.9+/-8.3 years old and the mean follow-up duration was 27.4+/-18.9 months. Demographic, clinical and radiologic characteristics were evaluated. The histological findings of specimens resected during the follow-up period were also analyzed. RESULTS: Ten (22.2%) out of 45 patients showed enlargement of the cysts during follow-up. Initial size of the cyst in patients with cyst enlargement were smaller than in patients without it in univariate analysis (p<0.01). Cysts less than 1.0 cm were significantly associated with cyst enlargement with odds ratio of 4.48 in multivariate analysis. Ten patients underwent surgical resection and pathologic examination revealed one carcinoma in situ and one invasive adenocarcinoma. The presence of mural nodule was associated with malignant change of IPMNs (p=0.02). None of unresected cases showed metastasis or disease-related death. CONCLUSIONS: Natural history of branch-duct type IPMNs is generally good. The occurrence of mural nodule is associated with the malignant change of the cyst but not the speed of size increment.

Natural History of Branch-Duct Type Intraductal Papillary Mucinous Neoplasm of the Pancreas / 대한소화기학회지

No abstract available.

Pancreaticoduodenectomy of Pancreatic Ductal Adenocarcinoma in the Elderly

PURPOSE: Pancreatic ductal adenocarcinoma has the highest incidence between the ages of 60 and 70 years. As the elderly population has been increasing in the last several decades, the proportion of patients older than 70 years of age with resectable pancreatic cancer is expected to increase in our society. This retrospective observation was performed to evaluate surgical value of pancreaticoduodenectomy for the elderly patients with pancreatic ductal adenocarcinoma. MATERIALS AND METHODS: From January 1990 to June 2005, among the patients who underwent pancreaticoduodenectomy for pancreatic ductal adenocarcinoma, the elder patients older than 70 years of age were retrospectively reviewed. Perioperative surgical outcomes, including general clinicopathologic features, morbidity, mortality, and survival outcomes, were investigated based on available medical records. RESULTS: Seventy-seven patients underwent pancreaticoduodenenctomy (PD) for pancreatic ductal adenocarcinoma. Among them, 11 patients (14.3%) were 70 years older. More frequent incidences of morbidity (8 out of 11 vs. 25 out of 65, p=0.049), especially delayed gastric emptying (3 out of 8 vs. 3 out of 66, p=0.035), were observed and overall length of hospital stay was also longer in the elderly (49.2 +/- 13.9 days vs. 36.1 +/- 13.2, p=0.012). However, no significant differences in mortality rate and survival outcomes were noted when comparing with those of the younger patients (p > 0.05). CONCLUSION: We agree with the opinion that age factor can not be absolute contraindication for pancreaticoduodenectomy, however, appropriate preoperative evaluations, proper patient selection considering life expectancy, advanced surgical techniques and detailed perioperative management are mandatory to guarantee the safety of pancreaticoduodenectomy performed in the elderly with pancreatic ductal adenocarcinoma.

Prótesis metálicas autoexpandibles en el manejo poliativo de la ictericia obstructiva maligna: experiencia local / Self-expandable metallic stents in the management of poliativo malignant obstructive jaundice: local experience

La ictericia obstructiva es una manifestación frecuente de las neoplasias que afectan la vía biliar. La obstrucción maligna del tracto biliar puede ser causada por Carcinoma ampular, Carcinoma Pancreático, Carcinoma del ducto biliar y Enfermedad metastásica. Estos tumores suelen tener mal pronóstico, de forma que una minoría son resecables en el momento del diagnóstico (10-20 por ciento) y, de ellos sólo una escasa proporción tienen expectativas de curación. Desde su primera descripción en el año 1979 las endoprótesis biliares se han tornado en un importante componente del manejo multimodal de este complejo problema clínico. Las prótesis biliares endoscópicas proveen pilación efectiva en estos pacientes, aliviando la ictericia y mejorando el estado nutricional y calidad de vida durante el tiempo restante de vida del paciente. Las prótesis metálicas autoexpandibles ofrecen un diámetro mayor que las plásticas y se asocian a una tasa de oclusión mas baja, eliminando la necesidad de recambio. En este trabajo presentamos nuestra experiencia en el tratamiento paliativo definitivo de la ictericia obstructiva maligna. Desde el 20-10-2000 hasta mayo del 2003, hemos colocado un total de 22 prótesis metálicas autoexpandibles en vía biliar. Un caso correspondió a una estenosis "benigna" del ducto hepático común que complicó una Cirugía de vesícula biliar. Los restantes 21 casos correspondieron a estenosis malignas siendo discriminadas de la siguiente manera: 12 casos de Tumores de cabeza de páncreas, 6 tumores del ducto biliar, 2 tumores de papila duodenal y un caso de infiltración de la pared coledociana por tumor de Vesicula biliar. El rango de edad de estos pacientes osciló entre 49 y 94 años con una edad promedio de 66 años. La sobrevida de estos pacientes ha oscilado entre 5 dìas y 2 años. No se presentaron complicaciones en el momento de la colocación de la prótesis. De los Tumores del ducto biliar, dos estaban localizados en la bifurcación.