Morphologic and Molecular Findings in Myxoid Hepatic Adenomas.

Myxoid hepatic adenomas are a rare subtype of hepatic adenomas with distinctive deposition of extracellular myxoid material between the hepatic plates. A total of 9 cases were identified in 6 women and 3 men with an average of 59±12 years. The myxoid adenomas were single tumors in 5 cases and multiple in 4 cases.

Metastatic pancreatic cancer with complete response to FOLFIRINOX treatment.

A 59-year-old woman presented with abdominal pain associated with nausea and night sweats. A large mass was found in the pancreatic tail and innumerable liver lesions were identified. Ultrasound-guided biopsy of a liver nodule confirmed moderately differentiated adenocarcinoma consistent with a pancreatobiliary primary.

Differing expression profiles of Notch/enterocyte and Wnt/secretory lineage signallings are associated with morphological diversity of appendiceal tumours.

Background: Tumours of appendix, including classic carcinoid tumour (CCT), goblet cell carcinoid (GCC), low-grade appendiceal mucinous neoplasm, high-grade appendiceal mucinous neoplasm/mucinous carcinoma (MCA) and non-mucinous adenocarcinoma (NMA), show different and sometimes mixed morphological features. It was hypothesised that these tumours originate from common tumour stem cell(s) with potential of various cell lineage differentiation. In normal intestinal epithelium, absorptive lineage (enterocytes) differentiation is driven by Notch-Hes1 pathway, while secretory lineage is driven by Wnt-Math1 pathway and further separated by different downstream signallings into three sublineages (Gfi1-Klf4/Elf3 for goblet cells, Gfi1-Sox9 for Paneth cells and Ngn3-Pdx1/Beta2/Pax4 for enteroendocrine cells).

Ileocaecal junction carcinoma: a clinicopathological study of 199 cases.

Aim: The ileocaecal junction (ICJ) region is an epithelial transition zone in which carcinomas are frequently diagnosed. However, it is currently unknown whether ICJ carcinomas (ICJ-CAs) have distinctive features. This study aimed to characterize the clinicopathological features of ICJ-CAs.

Is pneumatosis cystoides intestinalis gas-distended and ruptured lymphatics? Reappraisal by immunohistochemistry.

Context: Pneumatosis cystoides intestinalis (PCI) is a condition with multiple gas-filled cysts within the bowel wall, associated with diverse background diseases. Its pathogenesis is still a mystery. Some previous observations scattered in the literature have suggested an association of the cystic spaces in PCI with the lymphatics.

Interobserver variability in assessing dysplasia and architecture in colorectal adenomas: a multicentre Canadian study.

Aims: Following the introduction of colorectal cancer screening programmes throughout Canada, it became necessary to standardise the diagnosis of colorectal adenomas. Canadian guidelines for standardised reporting of adenomas were developed in 2011. The aims of the present study were (a) to assess interobserver variability in the classification of dysplasia and architecture in adenomas and (b) to determine if interobserver variability could be improved by the adoption of criteria specified in the national guidelines.

Appendiceal goblet cell carcinoid and mucinous neoplasms are closely associated tumors: lessons from their coexistence in primary tumors and concurrence in peritoneal dissemination.

Background: Goblet cell carcinoid (GCC) and appendiceal mucinous neoplasms (AMNs) are considered as different appendiceal tumors. Coexistence of both tumors was occasionally noted. We further observed the concurrence in both primary tumors and their peritoneal dissemination, that is, peritoneal carcinomatosis (PC) including pseudomyxoma peritonei (PMP).

Solitary lesions with fibrosis and increased IgG4+ plasma cells: part of the expanding spectrum of IgG4-related disease or a nonspecific inflammatory response?

We assessed 6 cases acquired during routine surgical sign-out for IgG4-related disease (IRD) according to criteria from a recent consensus meeting. These cases fulfilled the morphologic criteria-that is, dense lymphoplasmacytic infiltrates, IgG4:IgG ratio greater than or equal to 0.4, and fibrosis (storiform in 4 cases-but were associated with malignancy or did not fulfill the criteria for a new site.

Smad4 deficiency in T cells leads to the Th17-associated development of premalignant gastroduodenal lesions in mice.

While there is evidence that specific T cell populations can promote the growth of established tumors, instances where T cell activity causes neoplasms to arise de novo are infrequent. Here, we employed two conditional mutagenesis systems to delete the TGF-β signaling pathway component Smad4 in T cells and observed the spontaneous development of massive polyps within the gastroduodenal regions of mice. The epithelial lesions contained increased levels of transcripts encoding IL-11, IL-6, TGF-β, IL-1β, and TNF-α, and lamina propria cells isolated from lesions contained abundant IL-17A+CD4+ T cells.

Goblet cell carcinoids at extraappendiceal locations of gastrointestinal tract: an underrecognized diagnostic pitfall.

Background: Goblet cell carcinoid (GCC) is a clinicopathologically distinctive tumor that typically arises in appendix and metastasizes frequently. Although rare cases of ostensibly primary extraappendiceal GCC (EGCC) have been reported, the distinction from extraappendiceal metastasis of occult appendiceal primary may be problematic and has not been dealt with systematically in literature.

Methods: We reviewed our combined experience with EGCC at four North American hospitals and reevaluated all EGCC cases published in literature.

Juvenile polyposis of the stomach--a novel cause of hypergastrinemia.

Background: A 38-year-old female presented with a 3-year history of postprandial abdominal pain, refractory nausea, vomiting and hematemesis. She appeared malnourished and her symptoms were refractory to previous treatment with acid-suppressive drugs, prokinetics and antiemetics. Her medical history was significant for a diagnosis of juvenile polyposis syndrome at the age of 14 resulting in a transverse colectomy, and a diagnosis of Crohn's disease in her residual colon at the age of 35 resulting in a total colectomy.

Clinical experience of the multimodality management of anaplastic thyroid cancer and literature review.

Anaplastic Thyroid Carcinoma (ATC) is a rare thyroid tumor with a very aggressive clinical course. The following is a report of five patients with inoperable locally advanced disease treated at our institution using multimodality management consisting of chemotherapy and hyperfractionated accelerated radiotherapy. A flow diagram with management recommendations for inoperable ATC is suggested.

Autoimmune pancreatitis associated with renal lesions mimicking metastatic tumours.

Autoimmune pancreatitis is a chronic inflammatory disorder that is often misdiagnosed as pancreatic cancer. Since autoimmune pancreatitis is benign and responds to steroid management, it is important to diagnose it to avoid unnecessary surgical intervention. We describe a novel case of IgG4-associated autoimmune pancreatitis presenting with tubulointerstitial nephritis as renal lesions mimicking metastatic tumours but with no change in renal function.

Sessile serrated polyp mimicry in patients with solitary rectal ulcer syndrome: is there evidence of preneoplastic change?

Context: Solitary rectal ulcer syndrome (SRUS) is associated with erythema and ulceration of the rectal wall. Serrated lesions of the colon are divided into conventional hyperplastic polyps and a new set of lesions that are variably called sessile serrated polyps (SSPs) and sessile serrated adenomas. The SSPs are epithelial proliferative lesions that appear to act as a unique pathway to colorectal carcinogenesis.

Herpes simplex virus type II infection of ileum mesothelium: a case report and review of the literature.

Disseminated herpes simplex virus (HSV) infection usually manifests in the immunocompromised. However, anecdotal examples of visceral HSV disease and viremia have complicated type I diabetes. A case of a 53-year-old type I diabetic patient with bowel obstruction one week subsequent to bronchitis is reported.

Angiosarcoma of the colon and rectum: report of a case and review of the literature.

Angiosarcoma is a malignancy that occurs rarely in the gastrointestinal tract. We present a case of a 77-year-old male who had rectal bleeding and obstructive bowel symptoms. A large near-obstructing mass was seen endoscopically, but biopsies were inconclusive.

Verrucous carcinoma of the esophagus eluding multiple sets of endoscopic biopsies and endoscopic ultrasound: a case report and review of the literature.

A 56-year-old woman was noted to have a 5 cm to 6 cm long, irregular narrowing of the distal esophagus on an upper gastrointestinal series. Initial endoscopy revealed a polypoid mass in the distal esophagus and concurrent endoscopic ultrasound revealed changes typical of inflammation but no evidence of an obvious neoplastic process. Repeated biopsies revealed only inflammation with no evidence of malignancy.

Acute acalculous cholecystitis--a clinical-pathological disease spectrum.

Objective: To assess the influence of disease setting on clinical and pathological features of acute acalculous cholecystitis (AAC).

Design: Analysis of prospectively accumulated clinical data. Blinded histopathological review.