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Jorge Albores-Saavedra

Publications and source records attributed to Jorge Albores-Saavedra.

At least 19 recordsLinked to original sources
PubMed2007

HMB-45 reactivity in conventional uterine leiomyosarcomas.

We studied the human melanoma black-45 (HMB-45) reactivity in 25 uterine leiomyosarcomas including 23 conventional and 2 myxoid variants. Eleven tumors were poorly differentiated, and 14 were well to moderately differentiated. Nine uterine leiomyosarcomas labeled with HMB-45 in 10% or less of the tumor cells. Six were poorly differentiated and 3 were well differentiated. Our study indicates that 36% of conventional leiomyosarcomas focally express HMB-45. HMB-45 reactivity was more common in the poorly differentiated than in the well-differentiated group of leiomyosarcomas. In light of our findings and of those recently reported in the literature, we believe that the term PEComa should not be used for uterine leiomyosarcomas with clear cells or for conventional leiomyosarcomas that stain positively with HMB-45.

Adult↗
PubMed2006

Precancer: a conceptual working definition -- results of a Consensus Conference.

BACKGROUND: Precancers are lesions that precede the appearance of invasive cancers. The successful prevention or treatment of precancers has the potential to eliminate deaths due to cancer. METHODS: A National Cancer Institute-sponsored Conference on Precancer was convened on November 8-9, 2004, at The George Washington University Medical Center, Washington, DC. A definition of precancers was developed over 2 days of Conference discussions. RESULTS: The following five criteria define a precancer: (1) evidence must exist that the precancer is associated with an increased risk of cancer; (2) when a precancer progresses to cancer, the resulting cancer arises from cells within the precancer; (3) a precancer differs from the normal tissue from which it arises; (4) a precancer differs from the cancer into which it develops, although it has some, but not all, of the molecular and phenotypic properties that characterize the cancer; (5) there is a method by which the precancer can be diagnosed. CONCLUSIONS: The Conference participants developed a general definition for precancers that would provide a consistent and clinically useful way of distinguishing precancers from all other types of lesions. It was recognized that many precancerous lesions may not meet this strict definition, but the group felt it was necessary to define criteria that will help standardize clinical and biological studies. Furthermore, a set of defining criteria for putative precancer lesions will permit pathologists to build a diagnostically useful taxonomy of precancers based on specified clinical and biological properties. Precancers thus characterized can be classified into clinically relevant sub-groups based on shared properties (i.e. biomarkers, oncogenes, common metabolic pathways, responses to therapy, etc.). Publications that introduce newly described precancer entities should describe how each of the five defining criteria apply. This manuscript reviews the proposed definition of precancers and suggests how pathologists, oncologists and cancer researchers may determine when these criteria are satisfied.

Humans↗
PubMed2006

Pathology of genetically engineered mouse models of pancreatic exocrine cancer: consensus report and recommendations.

Several diverse genetically engineered mouse models of pancreatic exocrine neoplasia have been developed. These mouse models have a spectrum of pathologic changes; however, until now, there has been no uniform nomenclature to characterize these changes. An international workshop, sponsored by The National Cancer Institute and the University of Pennsylvania, was held from December 1 to 3, 2004 with the goal of establishing an internationally accepted uniform nomenclature for the pathology of genetically engineered mouse models of pancreatic exocrine neoplasia. The pancreatic pathology in 12 existing mouse models of pancreatic neoplasia was reviewed at this workshop, and a standardized nomenclature with definitions and associated images was developed. It is our intention that this nomenclature will standardize the reporting of genetically engineered mouse models of pancreatic exocrine neoplasia, that it will facilitate comparisons between genetically engineered mouse models and human pancreatic disease, and that it will be broad enough to accommodate newly emerging mouse models of pancreatic neoplasia.

Animals↗
PubMed2006

The sclerosing variant of adenoid cystic carcinoma: a previously unrecognized neoplasm of major salivary glands.

We report 2 cases of a previously unrecognized sclerosing variant of adenoid cystic carcinoma (ACC) of major salivary glands. One of the tumors arose in the parotid and the other in the submaxillary gland of young adult patients. The tumors were composed predominantly of varying-sized large sclerotic and hypocellular nodules containing myoepithelial cells and pseudovascular spaces, most likely the result of artifactual retraction. In moderately cellular nodules, there were numerous small globules or spherules surrounded by myoepithelial cells similar to those of collagenous or mucinous spherulosis. Focal cribriform areas and ductal structures lined by epithelial cells were also identified. Both tumors showed perineural invasion. Electron microscopy revealed that both large nodules and small globules or spherules were composed of excessive amounts of basement membrane and thick-banded collagen fibers. The myoepithelial cells showed immunoreactivity for smooth muscle actin (SMA), S100 protein, and vimentin. Collagen IV showed variable reactivity in both the large nodules and small spherules. More cases of the sclerosing variant of ACC and long-term follow-up of the patients are needed to determine the biologic behavior of this unusual but distinctive variant of ACC.

Adult↗
PubMed2006

Giant cell tumor of the extrahepatic biliary tree: a clinicopathologic study of 4 cases and comparison with anaplastic spindle and giant cell carcinoma with osteoclast-like giant cells.

We report four previously undescribed primary giant cell tumors of the extrahepatic biliary tree and morphologically compare them with 10 anaplastic spindle and giant cell carcinomas with osteoclast-like giant cells of the gallbladder. Two giant cell tumors were located in the distal common bile duct; one in the cystic duct and one in the gallbladder. The 3 patients with bile duct tumors were male, and the only patient with a gallbladder tumor was a female. The age of the patients ranged from 45 to 60 years with an average of 55 years. The patients with bile duct tumors presented with biliary obstruction, and the patient with a gallbladder tumor presented with symptoms of cholelithiasis and a gallbladder mass. Histologically, the tumors were similar to giant cell tumors of bone. They consisted of a mixture of mononuclear and multinucleated osteoclast-like giant cells. The mononuclear cells showed no atypical features, and their nuclei were similar to those of the multinucleated giant cells. CD163 immunoreactivity was restricted to the mononuclear cells, whereas CD68 and HAM 56 labeled only the multinucleated osteoclast-like giant cells. The mononuclear cells were EMA-positive but did not express cytokeratins. Follow-up showed that 3 patients were alive and disease-free 3.7 to 7 years after surgery. The anaplastic spindle and giant cell carcinomas contained a fewer number of osteoclast-like giant cells, and their mononuclear cells showed considerable variation in size and shape, marked cytologic atypia, and numerous mitotic figures. They were focally cytokeratin positive (AE1/AE3; CAM 5.2) and did not label with CD163, CD68, and HAM 56. The benign osteoclast-like giant cells showed immunoreactivity for CD68 and HAM 56 but were negative for CD163 and cytokeratins. Giant cell tumors of the extrahepatic biliary tree are benign true histiocytic neoplasms that should be distinguished from the highly lethal anaplastic spindle and giant cell carcinomas with osteoclast-like giant cells by detailed cytologic analysis and immunohistochemical stains for CD163, CD68, HAM 56, and cytokeratins.

Adenocarcinoma↗
PubMed2006

The clear cell variant of solid pseudopapillary tumor of the pancreas: a previously unrecognized pancreatic neoplasm.

Solid pseudopapillary tumor is a rare but distinctive pancreatic neoplasm whose cell phenotype remains a mystery. We report 3 cases of a previously undescribed variant of solid pseudopapillary tumor of the pancreas composed almost entirely of multivacuolated clear cells (>90%). The cytoplasmic vacuoles did not contain glycogen, mucin, or lipid but seemed to be formed by dilatation of the endoplasmic reticulum and mitochondria. The tumors displayed prominent trabeculae and a solid growth pattern but lacked the characteristic pseudopapillary pattern of the classical solid pseudopapillary tumor. In contrast, the clinical features, gross characteristics, and immunoprofile were similar to those of classical solid pseudopapillary tumor. Two of the patients were young adult females with well-demarcated tumors involving the body and tail of the pancreas. Tumor cells showed immunoreactivity for vimentin, CD10, CD56, synaptophysin, and nuclear accumulation of beta catenin. In 2 patients, 1 male and 1 female, the tumors were discovered incidentally. Despite vascular invasion in one of the tumors all 3 patients are disease free after distal pancreatectomy. Clues to distinguish the clear cell variant of solid pseudopapillary tumor from endocrine pancreatic tumor composed of clear cells, clear and foamy cell variants of ductal carcinoma, metastatic renal cell carcinoma, serous cystadenoma and ectopic adrenocortical nodules are provided.

Adenocarcinoma, Clear Cell↗
PubMed2006

The many faces and mimics of papillary thyroid carcinoma.

This article provides an overview of the 15 histologic variants of papillary thyroid carcinoma listed by the 2004 World Health Organization (WHO) monograph on endocrine tumors. The histologic features, differential diagnosis, and clinical course of each variant are discussed in some detail. The follicular variants (conventional and macrofollicular) constitute a morphologic challenge because the majority of these tumors are encapsulated and, also, because, in many tumors, not all neoplastic cells show the nuclear features considered to be diagnostic of papillary carcinoma. As a result, most of these tumors are missed even by experienced pathologists. Moreover, hyperplastic thyroid lesions, follicular adenomas, and Hashimoto's thyroiditis may contain cells with clear nuclei resembling those of papillary carcinoma. Papillary carcinomas composed entirely of hyperchromatic cells have been overlooked. The WHO monograph defines papillary carcinoma with focal spindle and giant cell carcinoma components but its clinical behavior is unknown. Papillary carcinoma with an insular pattern that does not show the artifactual separation of the cell nests has been misinterpreted as the solid variant of papillary carcinoma. Papillary microcarcinomas include not only the conventional type and the follicular variants but also the tall cell and columnar cell variants.

Adenocarcinoma, Papillary↗
PubMed2005

Classification of types of intraductal papillary-mucinous neoplasm of the pancreas: a consensus study.

Now that more than two decades have passed since the first reports of intraductal papillary-mucinous neoplasms (IPMNs), it has become clear that IPMN consists of a spectrum of neoplasms with both morphological and immunohistochemical variations. At a meeting of international experts on pancreatic precursor lesions held in 2003, it was agreed that a consensus classification of IPMN subtypes should be established to enable a more detailed analysis of the clinicopathological significance of the variations. Based on our experience and on information from the literature, we selected representative histological examples of IPMNs and defined a consensus nomenclature and criteria for classifying variants as distinctive IPMN subtypes including gastric type, intestinal type, pancreatobiliary type, and oncocytic type. These definitions can be used for further analyses of the clinicopathological significance of the variations of IPMN.

Biomarkers, Tumor↗
PubMed2005

Intestinal and oncocytic variants of pancreatic intraepithelial neoplasia. A morphological and immunohistochemical study.

We report 2 previously undescribed morphological variants of pancreatic intraepithelial neoplasia (PanIN). The first variant with an intestinal phenotype was associated with mucinous carcinomas that occurred in the tail of the pancreas of 2 men (60 and 65 years old). The carcinomas lacked the characteristic ovarian-like stroma of mucinous cystic neoplasms observed in female patients and did not show a papillary architecture. Whether they represent mucinous cystadenocarcinomas or mucinous carcinomas that arose from the flat variant of intraductal papillary mucinous neoplasms could not be determined with certainty. Microscopically, the intestinal type of PanIN was composed of pseudostratified columnar cells similar to those of colonic adenomas and showing variable degrees of dysplasia. A significant increase in the MIB-1 labeling index correlated with the severity of dysplasia. In contrast to conventional PanIN, the intestinal variant expressed MUC-2 and was MUC-1 negative. The second type of PanIN had an oncocytic phenotype, coexpressed MUC-2 and MUC-1 mucins, and was associated with intraductal oncocytic papillary carcinomas that showed a similar immunohistochemical mucin profile. Both intestinal and oncocytic types of PanIN expressed DPC4 and lacked p53 reactivity. The anatomical separation of the PanINs from the carcinomas and the gradual progression of cytological and architectural abnormalities in both variants of PanIN argue against ductal spread (cancerization of the ducts). The intestinal and oncocytic variants of PanIN broaden the morphological spectrum of this intraductal lesion. Although their significance is unknown, the possibility that these PanIN variants represent cancer precursors should be considered.

Adenocarcinoma, Mucinous↗
PubMed2005

CD56 reactivity in small cell carcinoma of the uterine cervix.

Small cell carcinoma (SCC) of the uterine cervix, like its pulmonary counterpart, is a rare but distinctive neoplasm that should be separated from nonendocrine carcinomas because of its highly aggressive clinical course and response to chemotherapy and irradiation. CD56 (neural cell adhesion molecule) has recently been shown to be the best marker for the diagnosis of pulmonary SCC. In this study, we assessed the sensitivity and specificity of CD56 in the diagnosis of SCC of the uterine cervix compared with those of chromogranin and synaptophysin. Twenty-two (88%) of 25 SCCs of the uterine cervix labeled with CD56 in a predominantly membranous and diffuse pattern, whereas 16 of 25 (64%) stained with synaptophysin in a predominantly diffuse pattern and 8 of 25 (32%) showed predominantly focal immunoreactivity for chromogranin. In contrast, 3 of 21 (14%) moderately to poorly differentiated squamous cell carcinomas and 1 of 16 (6%) moderately differentiated adenocarcinomas showed focal immunoreactivity for CD56. Although not specific, CD56 seems to be the most sensitive marker for the diagnosis of SCC of the uterine cervix. Moreover, its diffuse reactivity reduces the possibility of obtaining negative results in small biopsy samples.

Biomarkers, Tumor↗
PubMed2005

High-grade neuroendocrine carcinoma of the ampulla of vater: a clinicopathologic and immunohistochemical analysis of 14 cases.

We describe the clinical and pathologic features of 14 cases of high-grade neuroendocrine carcinoma (HGNEC) of the ampulla of Vater classified according to WHO classification of lung tumors into small cell carcinoma (SCC, 6 cases) and large cell neuroendocrine carcinoma (LCNEC, 8 cases) types. The immunohistochemical findings were compared with those of 13 cases of primary poorly differentiated ampullary adenocarcinomas (PDACA) lacking neuroendocrine morphology. The mean age of 10 males and 4 females was 70 years. The mean tumor size was 2.5 cm. Ten of 13 patients had lymph node metastases (mean, 2.3 nodes involved). Documented sites of distant metastases included brain and liver. Overall, 64% of patients with ampullary HGNEC died of disease (mean follow-up, 14.5 months). Four patients had no evidence of disease after resection (mean, 20 months). Half of the tumors were associated with adenomas of the adjacent mucosa, 2 with high-grade dysplasia. Two HGNECs were combined with a conventional adenocarcinoma and another with a squamous cell carcinoma component. By immunohistochemistry, the HGNECs were positive for cytokeratins (AE1/AE3, 100%; Cam5.2, 67%; CK7, 87%; CK20, 38%), similar to the pattern found in PDACAs. p27 expression was lost in 1 case of HGNEC and in all PDACAs. Retinoblastoma (Rb) protein expression was lost in 60% of HGNECs and in none of the PDACA cases. In conclusion, HGNECs of the ampulla are rare (2%-3% of ampullary tumors in our material). The clinical course parallels that of their pulmonary counterparts and appears to be worse than that of locally advanced ampullary adenocarcinomas. The association with adenoma and or conventional adenocarcinoma components may suggest a common pathway in the initial carcinogenesis of these two types of tumors. Loss of Rb expression, a characteristic finding in pulmonary SCCs, is present in almost half of ampullary HGNECs. In contrast, p27 expression is lost in PDACAs and retained in most HGNECs. Thus, there are differences in the molecular phenotypes of these two types of ampullary carcinoma, supporting the distinction of poorly differentiated carcinomas with a neuroendocrine phenotype from those without.

Adenocarcinoma↗
PubMed2005

Cylindroma (dermal analog tumor) of the breast: a comparison with cylindroma of the skin and adenoid cystic carcinoma of the breast.

We compared 4 breast cylindromas with 50 dermal cylindromas and 8 adenoid cystic breast carcinomas. Except for a modest increase in the number of eccrine ducts and reactive Langerhans cells in dermal cylindromas, breast and dermal cylindromas showed identical histologic and immunohistochemical features. Both were characterized by epithelial islands containing central basaloid cells and peripheral myoepithelial cells surrounded by a thickened, continuous, periodic acid-Schiff-positive basement membrane that was immunoreactive for collagen IV. Clusters of sebaceous cells and a few eccrine ducts are described in breast cylindromas. Cytokeratin 7 labeled predominantly the central basaloid cells, and smooth muscle actin stained peripheral myoepithelial cells in breast and dermal cylindromas. Eccrine ducts were highlighted by epithelial membrane antigen and carcinoembryonic antigen. S-100 protein and CD1a showed a variable number of dendritic Langerhans cells. Cylindromas of the breast and skin did not express cytokeratin 20, gross cystic disease fluid protein 15, or estrogen or progesterone receptor. Breast cylindroma might be confused with the solid variant of adenoid cystic carcinoma, especially in needle core biopsy specimens, because they share nodular and trabecular patterns, basaloid cells, myoepithelial cells, eccrine ducts, and hyaline globules of basement membrane material. However, adenoid cystic carcinoma displays an infiltrative growth pattern, cytologic atypia, and mitotic figures and lacks the continuous, thickened basement membrane.

Aged↗
PubMed2005

Plexiform neurofibroma of the uterine cervix: a case report and review of the literature.

The female genital system is rarely affected in von Recklinghausen neurofibromatosis. The vulva is the most frequent genital location, but vaginal, cervical, uterine, and ovarian neurofibromas have rarely been reported. We describe a case of plexiform neurofibroma affecting the uterine cervix in a patient with chronic pelvic pain and menorrhagia who had multiple cutaneous neurofibromas and 1 large paraspinal neurofibroma. A small plexiform neurofibroma, which was not grossly visible, was confined to the uterine cervix and coexisted with a uterine leiomyoma and adenomyosis. There were no neurofibromas in the myometrium, fallopian tubes, or ovaries. Plexiform neurofibroma is a neoplasm that should be considered in the differential diagnosis of spindle cell neoplasms of the uterine cervix, especially in specimens from patients with neurofibromatosis.

Actins↗
PubMed2005

Papillary carcinomas of the gallbladder: analysis of noninvasive and invasive types.

CONTEXT: Although papillary carcinomas have been recognized as distinct morphologic variants of gallbladder neoplasms, they have been lumped together in a single group despite the recognition of noninvasive and invasive types. As a result, the biologic behavior of each type remains undescribed. OBJECTIVE: To compare the biologic behavior of noninvasive and invasive papillary carcinomas of the gallbladder. DESIGN: The clinical and morphologic features of 16 noninvasive papillary carcinomas (>1 cm) of the gallbladder were analyzed, and their clinical behavior was compared with that of 370 invasive papillary carcinomas recorded in the Survey Epidemiology and End Results (SEER) Program of the National Cancer Institute from 1973 through 2001. The biologic behavior of invasive papillary carcinomas was compared with that of invasive nonpapillary carcinomas of the gallbladder recorded in SEER. Hematoxylin-eosin-stained sections were available for review in the 16 noninvasive papillary carcinomas. The number of slides examined per case varied from 3 to 16, with an average of 7. RESULTS: The 16 patients with noninvasive papillary carcinomas included 11 women and 5 men, aged 34 to 83 years (mean age, 61 years). Thirteen patients had cholelithiasis. Laparoscopic cholecystectomy was performed on 12 patients and open cholecystectomy on 4. The tumors measured from 1.3 to 8.6 cm and were well to moderately differentiated. Fourteen noninvasive papillary carcinomas showed biliary phenotype, and 2 showed intestinal phenotype. Follow-up was obtained in 11 patients; 6 were asymptomatic 5 to 11 years after surgery, 2 were symptom free 9 months to 4 years following cholecystectomy, and 3 died of unrelated causes 2 to 3 years after surgery. Three hundred seventy cases of invasive papillary carcinomas were recorded in SEER. The 10-year relative survival rate for 225 patients with invasive papillary carcinomas confined to the gallbladder wall was 52%, while the 10-year relative survival rate for 83 patients with papillary carcinomas that had spread to the lymph nodes was less than 10%. Of the remaining 62 invasive papillary carcinomas, 58 had distant metastases and 4 were not staged. The 10-year relative survival rate for invasive nonpapillary carcinomas confined to the gallbladder wall was 30%. CONCLUSION: Noninvasive papillary carcinomas of the gallbladder-regardless of size, cell phenotype, and degree of differentiation-do not metastasize, and a simple cholecystectomy appears to be a curative procedure. In contrast, invasive papillary carcinomas do metastasize and are associated with a poor prognosis (10-year relative survival rate for tumors confined to the gallbladder wall was 52%, while the 10-year relative survival rate for tumors with lymph node metastasis was <10%). The separation of papillary carcinomas into noninvasive and invasive types is clinically relevant and therefore fully justified.

Adult↗
PubMed2004

Intraductal tubular adenoma, pyloric type, of the pancreas: additional observations on a new type of pancreatic neoplasm.

Three cases of a distinctive intraductal tubular adenoma, pyloric type, of the main pancreatic duct are reported. The patients, two women and a man, whose ages ranged from 63 to 70 years, complained of abdominal pain attributed to chronic pancreatitis in two patients. The patient with the largest tumor also had symptoms of gastric outlet obstruction. The tumors, two of which arose in the head and one in the tail of the pancreas, led to occlusion and cystic dilatation of the main pancreatic duct. Two adenomas were sessile and one was attached to the wall of the pancreatic duct by a thin fibrous stalk. Microscopically, they were composed of lobules of closely packed tubular glands similar to pyloric glands. In one tumor, nearly all glands were lined by columnar mucin-secreting cells with abundant clear cytoplasm and basally oriented nuclei. In addition to pyloric glands, two adenomas contained glands lined by cells with little or no mucin as well as by pink oncocytic cells. Focal intestinal differentiation was identified in one tumor. Both intracellular and extracellular mucin was detected with the mucicarmine, periodic acid-Schiff, and alcian blue stains. All three adenomas were CK7 positive and CK20 negative. Focal carcinoembryonic antigen linear reactivity along the apical cytoplasm was seen in many cells, but few cells expressed cytoplasmic carcinoembryonic antigen. All three adenomas showed low proliferative activity as measured by the MIB-1 labeling index. The three adenomas were p53 negative and showed loss of DPC4 expression. No endocrine cells were identified in any of the tumors. All patients are alive and symptom free from 4 months to 5 years following surgical treatment.

Adenoma↗
PubMed2004

In situ and invasive adenocarcinomas of the gallbladder extending into or arising from Rokitansky-Aschoff sinuses: a clinicopathologic study of 49 cases.

We report 49 cases of gallbladder carcinomas that extended into or originated from Rokitansky-Aschoff sinuses (RAS), all of which were resected by laparoscopic cholecystectomy. Twenty-one tumors were in situ carcinomas that extended along RAS; six in situ carcinomas arose in adenomyomatous hyperplasia and 22 were invasive adenocarcinomas with extension into RAS. Thirty-seven patients were women and 12 men. Forty patients had cholelithiasis. The age of the patients ranged from 55 to 84 years (mean 67 years). All in situ carcinomas were incidental microscopic findings in gallbladders removed for cholelithiasis and/or cholecystitis. No patient with in situ carcinoma died as a result of the tumor, including two with in situ carcinoma that originated in adenomyomatous hyperplasia and showed microinvasion. In contrast, of 15 patients with invasive well to moderately differentiated adenocarcinoma extending into RAS and invading the muscle layer or subserosal connective tissue, 8 died 2 to 4 years after surgery. Seven patients survived 1 to 8 years after cholecystectomy. Useful clues to separate RAS with in situ carcinoma from tubular neoplastic invasive glands were the following: connection of the epithelial invaginations to the surface epithelium, recognition of normal biliary epithelium admixed with neoplastic epithelium, presence of inspissated bile in long dilated spaces, and lack of invasion to the smooth muscle bundles. In situ carcinoma spreading along RAS consisted of long tubular often dilated structures extending through the intermuscular connective tissue, whereas neoplastic glands were usually small or of medium size that invaded smooth muscle bundles or intermuscular connective tissue. Perineural invasion was seen only in invasive glands located in the subserosal connective tissue. Two cases of in situ carcinoma that arose in adenomyomatous hyperplasia and three invasive adenocarcinomas that were composed predominantly of tall columnar mucin containing cells similar to gastric foveolar cells with varying degrees of atypia and cells with biliary phenotype bear some resemblance to intraductal papillary mucinous carcinoma of the pancreas or to mucinous cystic pancreatic neoplasm. Metaplastic pyloric glands often seen in the muscle layer and subserosal connective tissue maintain their lobular pattern and should not be confused with invasive glands. Our findings indicate that distinction of in situ carcinoma spreading into RAS from tubular neoplastic glands of invasive adenocarcinomas is crucial to determine prognosis in this group of patients with gallbladder carcinoma.

Adenocarcinoma↗
PubMed2004

An illustrated consensus on the classification of pancreatic intraepithelial neoplasia and intraductal papillary mucinous neoplasms.

Invasive pancreatic ductal adenocarcinoma is an almost uniformly fatal disease. Several distinct noninvasive precursor lesions can give rise to invasive adenocarcinoma of the pancreas, and the prevention, detection, and treatment of these noninvasive lesions offers the potential to cure early pancreatic cancers. Noninvasive precursors of invasive ductal adenocarcinoma of the pancreas include pancreatic intraepithelial neoplasias (PanINs), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms. Diagnostic criteria, including a distinct ovarian-type stroma, and a consistent nomenclature are well established for mucinous cystic neoplasms. By contrast, consistent nomenclatures and diagnostic criteria have been more difficult to establish for PanINs and IPMNs. Because both PanINs and IPMNs consist of intraductal neoplastic proliferations of columnar, mucin-containing cells with a variable degree of papilla formation, the distinction between these two classes of precursor lesions remains problematic. Thus, considerable ambiguities still exist in the classification of noninvasive neoplasms in the pancreatic ducts. A meeting of international experts on precursor lesions of pancreatic cancer was held at The Johns Hopkins Hospital from August 18 to 19, 2003. The purpose of this meeting was to define an international acceptable set of diagnostic criteria for PanINs and IPMNs and to address a number of ambiguities that exist in the previously reported classification systems for these neoplasms. We present a consensus classification of the precursor lesions in the pancreatic ducts, PanINs and IPMNs.

Carcinoma in Situ↗