Faculty Bibliography

Although vascular invasion is a well-established indicator of poor prognosis for patients with infiltrating ductal adenocarcinoma of the pancreas (PDAC), the histopathologic characteristics of vascular invasion are not well described. Hematoxylin and eosin-stained slides from 209 surgically resected infiltrating PDACs were systematically evaluated for the presence or absence of microscopic vascular invasion. For the cases with vascular invasion, we further categorized the histologic pattern of invasion into conventional and pancreatic intraepithelial neoplasia-like (PanIN-like). In addition, several histopathologic factors in the surrounding blood vessels, including lymphocytic infiltration and luminal fibrosis, were carefully assessed. Data were compared with clinicopathologic variables, including patient survival. Microscopic vascular invasion was observed in 136 of the 209 PDACs (65.1%). Vascular invasion mimicking pancreatic intraepithelial neoplasia (PanIN-like invasion) was observed in 94 of the 136 cases (69.1%) with vascular invasion. Microscopic vascular invasion was associated with increased tumor size (P=0.04), higher pT classification (P=0.003), lymph node metastasis (P<0.0001), and perineural invasion (P=0.005). Vascular invasion was inversely correlated with neo-adjuvant therapy (P<0.0001). Examination of adjacent blood vessels revealed that peritumoral blood vessels with intimal lymphocytes (P=0.002), intimal (P=0.007) and medial (P=0.001) fibrosis, and cancer cells in vascular wall (P<0.0001) were all highly associated with the intraluminal vascular invasion. In univariate analysis, patients whose cancers had microscopic vascular invasion (median survival, 15.3 mo) had a significantly worse survival than did patients with carcinomas without vascular invasion (25.1 mo; P=0.01, log-rank test). Microscopic vascular invasion is a poor prognostic indicator and can histologically mimic PanIN.

OBJECTIVE:To examine the clinicopathologic features and clonal relationship of multifocal intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. BACKGROUND:Intraductal papillary mucinous neoplasms are increasingly diagnosed cystic precursor lesions of pancreatic cancer. Intraductal papillary mucinous neoplasms can be multifocal and a potential cause of recurrence after partial pancreatectomy. METHODS:Thirty four patients with histologically documented multifocal IPMNs were collected and their clinicopathologic features catalogued. In addition, thirty multifocal IPMNs arising in 13 patients from 3 hospitals were subjected to laser microdissection followed by KRAS pyrosequencing and loss of heterozygosity (LOH) analysis on chromosomes 6q and 17p. Finally, we sought to assess the clonal relationships among multifocal IPMNs. RESULTS:We identified 34 patients with histologically documented multifocal IPMNs. Synchronous IPMNs were present in 29 patients (85%), whereas 5 (15%) developed clinically significant metachronous IPMNs. Six patients (18%) had a history of familial pancreatic cancer. A majority of multifocal IPMNs (86% synchronous, 100% metachronous) were composed of branch duct lesions, and typically demonstrated a gastric-foveolar subtype epithelium with low or intermediate grades of dysplasia. Three synchronous IPMNs (10%) had an associated invasive cancer. Molecular analysis of multiple IPMNs from 13 patients demonstrated nonoverlapping KRAS gene mutations in 8 patients (62%) and discordant LOH profiles in 7 patients (54%); independent genetic alterations were established in 9 of the 13 patients (69%). CONCLUSIONS:The majority of multifocal IPMNs arise independently and exhibit a gastric-foveolar subtype, with low to intermediate dysplasia. These findings underscore the importance of life-long follow-up after resection for an IPMN.

Poorly differentiated neuroendocrine carcinomas (NECs) of the pancreas are rare malignant neoplasms with a poor prognosis. The aim of this study was to determine the clinicopathologic and genetic features of poorly differentiated NECs and compare them with other types of pancreatic neoplasms. We investigated alterations of KRAS, CDKN2A/p16, TP53, SMAD4/DPC4, DAXX, ATRX, PTEN, Bcl2, and RB1 by immunohistochemistry and/or targeted exomic sequencing in surgically resected specimens of 9 small cell NECs, 10 large cell NECs, and 11 well-differentiated neuroendocrine tumors (PanNETs) of the pancreas. Abnormal immunolabeling patterns of p53 and Rb were frequent (p53, 18 of 19, 95%; Rb, 14 of 19, 74%) in both small cell and large cell NECs, whereas Smad4/Dpc4, DAXX, and ATRX labeling was intact in virtually all of these same carcinomas. Abnormal immunolabeling of p53 and Rb proteins correlated with intragenic mutations in the TP53 and RB1 genes. In contrast, DAXX and ATRX labeling was lost in 45% of PanNETs, whereas p53 and Rb immunolabeling was intact in these same cases. Overexpression of Bcl-2 protein was observed in all 9 small cell NECs (100%) and in 5 of 10 (50%) large cell NECs compared with only 2 of 11 (18%) PanNETs. Bcl-2 overexpression was significantly correlated with higher mitotic rate and Ki67 labeling index in neoplasms in which it was present. Small cell NECs are genetically similar to large cell NECs, and these genetic changes are distinct from those reported in PanNETs. The finding of Bcl-2 overexpression in poorly differentiated NECs, particularly small cell NEC, suggests that Bcl-2 antagonists/inhibitors may be a viable treatment option for these patients.

BACKGROUND:Surgical resection remains the only potentially curative option for patients with pancreatic adenocarcinoma (PAC). Advances in surgical technique and perioperative care have reduced perioperative mortality; however, temporal trends in perioperative morbidity and the use of adjuvant therapy on a population basis remain ill-defined. STUDY DESIGN/METHODS:Using Surveillance, Epidemiology, and End Results-Medicare data, 2,461 patients with resected PAC were identified from 1991 to 2005. We examined trends in preoperative comorbidity indices, adjuvant treatment, type of pancreatic resection, and changes in morbidity and mortality during 4 time intervals (ie, 1991-1996, 1997-2000, 2001-2003, and 2003-2005). RESULTS:The majority of patients underwent pancreaticoduodenectomy (n = 1,945; 79%). There was a temporal increase in mean patient age (p < 0.05) and the number of patients with multiple preoperative comorbidities (Elixhauser comorbidities ≥3: 1991-1996, 10% vs 2003-2005, 26%; p < 0.001). Perioperative morbidity (53%) did not, however, change over time (p = 0.97) and 30-day mortality decreased by half (1991-1996: 6% vs 2003-2005: 3%; p = 0.04). Overall, 51% (n = 1,243) of patients received adjuvant therapy, with the majority receiving chemoradiation (n = 817; 33%). Among patients who received adjuvant therapy, factors associated with receipt of adjuvant chemotherapy alone relative to chemoradiation included older patient age (odds ratio = 1.75; p < 0.001) and ≥3 medical comorbidities (odds ratio = 1.57; p = 0.007). Receipt of adjuvant chemotherapy alone also increased over time (2003-2005 vs 1991-1996, odds ratio = 2.21; p < 0.001). CONCLUSIONS:Perioperative 30-day mortality associated with resection for PAC decreased by one-half from 1991 to 2005. Although patients undergoing resection for PAC were older and had more preoperative comorbidities, the incidence of perioperative complications remained stable. The relative use of adjuvant chemotherapy alone vs chemoradiation therapy for PAC has increased in the United States during the 15 years examined.

INTRODUCTION/BACKGROUND:Solid pseudopapillary neoplasms are rare pancreatic neoplasms with low malignant potential and favorable prognosis that are typically seen in young women. PRESENTATION OF CASE/METHODS:We report a case of two large solid pseudopapillary neoplasms in a 23-year old woman who was treated successfully with a total pancreatectomy. CONCLUSION/CONCLUSIONS:To the best of our knowledge, this is the first report of two discrete solid pseudopapillary neoplasms in the same patient.

OBJECTIVE:Autoimmune pancreatitis (AIP) is an inflammatory, IgG4-associated condition that often overlaps clinically and radiographically with pancreatic ductal adenocarcinoma. We reviewed our institutional experience with fine needle aspiration (FNA) cytology in patients subsequently diagnosed with AIP. STUDY DESIGN/METHODS:A retrospective review was conducted of FNA results correlating to all surgical pancreatic specimens diagnosed as AIP or lymphoplasmacytic sclerosing pancreatitis from 1984 to 2011. RESULTS:AIP was diagnosed in 15 cases by surgical resection and in 2 by combined clinical findings and nondiagnostic biopsies. Of 20 aspirates from 17 patients, 1 was diagnosed as malignant, 1 as neoplasm (mucinous), 10 as atypical, 5 as benign, and 3 as scant or nondiagnostic. Of the 10 aspirates diagnosed as atypical, 1 was suspicious for malignancy, 1 could not exclude neuroendocrine neoplasm, 1 was markedly atypical, and 7 demonstrated scattered ductal atypia. Common morphologic features included hypocellularity, focal-to-marked ductal epithelial atypia, fibrous tissue fragments, and a smear background lacking red blood cells. CONCLUSION/CONCLUSIONS:On FNA, AIP most often leads to an 'atypical' cytopathologic interpretation and rarely may be diagnosed as adenocarcinoma. Thus, caution is warranted to avoid overdiagnosis on FNA when a mass lesion is reported in a patient with clinical or radiographic suspicion of AIP.

PURPOSE:To analyze a single-center experience with locally advanced pancreatic cancer (LAPC) patients treated with chemoradiation (CRT) and to evaluate predictive variables of outcome. METHODS AND MATERIALS:LAPC patients at our institution between 1997 and 2009 were identified (n = 109). Progression-free survival (PFS) and overall survival (OS) were assessed using Kaplan-Meier analysis. Cox proportional hazard models were used to evaluate predictive factors for survival. Patterns of failure were characterized, and associations between local progression and distant metastasis were explored. RESULTS:< .0001). CONCLUSIONS:LAPC patients who suffer local progression following definitive CRT may experience inferior OS and increased risk of metastasis, warranting efforts to improve control of local disease. However, patients with poor pretreatment performance status, elevated CA19-9 levels, and treatment interruptions may experience poor outcomes despite aggressive management with CRT, and may optimally be treated with induction chemotherapy or supportive care. Novel therapies aimed at controlling both local and systemic progression are needed for patients with LAPC.