Pseudoneoplasms of the gastrointestinal tract

[Enteritis cystica profunda]

Enteritis cystica profunda is a rare and benign disease defined as the invagination of the intestinal epithelium into the submucosa and more profound layers of intestinal wall leading to the formation of mucin-filled cystic spaces. We reported the case of a 45-year-old female, suffering from a Crohn's disease, with a Koenig's syndrome, diarrhea, abdominal pain and weight loss. The colonoscopy and the abdominopelvic scan showed a terminal ileal stenosis, with parietal calcifications. A surgical ileocecal resection was decided. Gross examination of the ileocecal resection showed a thickening of the ileal wall, with many mucin-filled cysts measuring 1mm to 2cm, with some calcifications. The ileal mucosa was ulcerated, and showed a stenotic sector extending over 3cm. Histological examination showed acute ulcerated ileitis lesions, with chronic ileitis lesions and stenosis, compatible with the known diagnosis of Crohn's disease. There were also many cysts into the ileal wall. They were lined with a regular ileal epithelium. The cysts contained mucus, with some calcifications. Some cysts were ruptured, with extravasation of mucus within the wall. Cystica profunda can be found anywhere along the digestive tract. The physiopathology is not yet well understood, but it seems to be favored by chronic aggression of the intestinal wall. This pathology most often coexists with Crohn's disease. The main differential diagnosis is mucinous adenocarcinoma. Cystica profunda does not require any specific treatment.

Lymphoglandular Complex-Like Colorectal Carcinoma-A Series of 20 Colorectal Cases, Including Newly Reported Features of Malignant Behavior

Distinguishing colon carcinoma that is surrounded by well-circumscribed lymphoid tissue from adenomas involving lymphoglandular complexes can be difficult. We assessed a multi-institutional international cohort of 20 colorectal carcinomas with associated prominent lymphoid infiltrates, which we referred to as lymphoglandular complex-like carcinoma (LGCC). We collected clinical and endoscopic features, including lesion size, endoscopic appearance, location, procedure, follow-up, AJCC stage, and mismatch repair status. We recorded the presence of the following histologic features: haphazard gland distribution, gland angulation, gland fusion, solid nest formation, single-cell formation, stromal desmoplasia, presence of lymphovascular invasion and perineural invasion, presence of lamina propria, cytologic atypia as low- or high-grade, presence of goblet cells in the invasive component, and the presence of a surface lesion. Most cases (9 of 13) were described endoscopically as sessile polyps with an average size of 1.56 cm. Most cases (90%) were associated with a surface lesion, of which the majority were tubular adenomas, though a subset was associated with sessile serrated lesions with dysplasia (3 of 18). All cases of LGCC demonstrated haphazard gland distribution and either gland angulation, fusion, or solid nest formation. A portion of cases demonstrated single-cell infiltration (35%) and desmoplasia (50%), and rarely lymphovascular invasion was present (5%). A subset (10%) of cases invaded beyond the submucosa. Deficient mismatch repair was present in 22% (2 of 9) of cases for which it was performed. In cases of colectomy or completion colectomy, nodal metastasis was present in 38% (3 of 8). No cases demonstrated disease recurrence or disease-specific mortality. Overall, LGCC represents an enigmatic subset of carcinomas that is important to distinguish from adenomas involving lymphoglandular complexes due to its varying prognostic outcomes.

Malakoplakia of the small intestine presenting as an abdominal mass

Malakoplakia is a rare chronic granulomatous disease that typically involves the urinary and gastrointestinal tracts of immunocompromised individuals. Characteristic histologic features include von Hansemann cells and Michaelis-Gutmann bodies. Clinical manifestations, based on the organ system effected, range from cutaneous lesions, irritative urinary symptoms, and hematochezia. We report a rare example of malakoplakia presenting as an abdominal mass with extensive intestinal and pelvic involvement complicated by a superficial polymicrobial abscess. This case report aims to describe the proposed pathogenesis, variable clinical presentation, and surgical management of malakoplakia.

Pitfalls in the reporting of neoplastic and pseudo neoplastic lesions in the colon and rectum

INTRODUCTION

Colonic biopsies comprise large portion of pathologists' daily work. Within various pathological entities, there are histological ranges and variations. Unawareness of all of these variabilities might lead to misdiagnosis by an inexperienced pathologist and, accordingly, to mismanagement.

Enteritis cystica profunda with lipoma in the second portion of the duodenum

Enteritis cystica profunda (ECP), a rare and benign condition, is defined as the displacement of the glandular epithelium into the submucosa and more profound layers of the small intestinal wall leading to the formation of mucin-filled cystic spaces. ECP frequently occurs in the ileum or jejunum and is associated with diseases such as Crohn disease and Peutz-Jeghers syndrome. ECP also develops in the absence of known pathology. ECP in the duodenum is very rare and mostly occurs without associated conditions. In this report, we present a rare case of ECP without an associated disease, in the second portion of the duodenum distal to the ampulla of Vater and coexisting with lipoma within the polypoid lesion.

Endoscopic mucosal resection of a large inflammatory fibroid polyp (Vanek's tumor): a case report

Vanek’s Tumor (inflammatory fibroid polyp) is a rare benign mesenchymal lesion occurring throughout the digestive tract. Classical Vanek’s tumor (“gastric”) contains concentric formations of proliferating spindle cells, which are CD34 positive. Atypical-inflammatory pseudotumor-like Vanek’s tumor (“intestinal”) lacks concentric formations and is CD34 negative. A 70-years-old man patient presented during hematochemical routine tests, sideropenic anemia and leukopiastrinosis. The patient performed osteomyelitis biopsy and esophagogastroduodenoscopy (EGD) showing a gastric wall with nodular appearance and, in antrum pre-pyloric, a polypoid pedunculated lesion, measuring approximately 3 cm in diameter, surrounded by hyperemic mucosa. The lesion then was removed by en bloc endoscopic mucosal resection (EMR) and histo-morphological, immune-cytochemical and biomolecular evaluations were performed. The data were compatible with a benign polyp fibroid inflammatory (Vanek’s Tumor). The results of this study suggest that endoscopic mucosal resection is a safe and efficacy solution for the resection of these gastrointestinal polyps and the two morphological patterns of Vanek’s tumor more probably represent only variants of one type of tumor than two different lesions. BRAF mutations were not shown growth PDGFRA wild-type Vanek’s tumor. (www.actabiomedica.it)

Incidental mesonephric remnant hyperplasia of the jejunal mesentery: A diagnostic challenge

Mesonephric remnants are embryonic vestiges of the mesonephric (Wolffian) ducts which regress during normal development. These remnants have been uncommonly reported in the female and male reproductive tract as a spectrum of morphologic lesions that can be misdiagnosed as carcinoma. One case of mesonephric remnant hyperplasia of the jejunal mesentery incidentally found in a 47-year-old man is herein reported. This is the first description of mesonephric hyperplasia arisen in the mesentery. The presence of ducts, tubules, and cysts lined by bland, epithelial, cuboidal cells with scant cytoplasm, and diffuse pseudoinfiltrative growth pattern can raise the possibility of neoplasia. Immunohistochemically, mesonephric epithelia have a characteristic staining. CD10 highlights the apical-luminal aspect of the cells. Besides, intense reactivity is showed for high-molecular-weight cytokeratin (CK), CK7, bcl2, and vimentin. The main differential diagnosis includes mesothelial hyperplasia, epithelial mesothelioma, well-differentiated neuroendocrine tumor, and infiltration due to acinar adenocarcinoma of the prostate. However, a detailed microscopic study with the aid of immunohistochemistry helps separate mesonephric remnants from malignant processes. The mesonephric hyperplasia of the mesentery we have reported adds to the spectrum of mesonephric remnants a new location. Familiarity with this lesion is indispensable to avoid overdiagnosis.

Bizarre stromal cells in Crohn's disease

Lesions with bizarre stromal cells (BSC) have been described in many organs and, although benign, they are frequently misdiagnosed as malignancy. We present the first case of BSC in Crohn’s disease with a rare submucosal topography and we review the related literature. We hypothesize that, in Crohn’s disease, BSC of myofibroblastic origin may be related to the development of submucosal fibrosis.

Florid Vascular Proliferation of the Small Bowel and Colon, a Potential Masquerader of Malignancy: Report of Three Cases

Vascular abnormalities and lesions of the small bowel and colon are rare. A florid vascular proliferation (FVP) associated with colon obstruction and intussusception has been described and can mimic malignant vascular tumors such as angiosarcoma. In this article, we report a case of colonic FVP associated with colon obstruction, a case of small bowel FVP associated with a Meckel's diverticulum, and a case of small bowel FVP with intussusception. All cases occurred in older adults (mean 73 years of age, range 62-80 years of age). FVP grossly appeared as a mass-like lesion in one small bowel case, while the other cases did not demonstrate a grossly identifiable mass. Histologically, all cases demonstrated a transmural vascular proliferation with plump endothelial cells. No significant cytologic atypia was seen, and mitotic figures were rare. No recurrence was seen in all cases with an average follow-up of 22 months. It is important to be aware of this entity as it appears to be a nonneoplastic reactive process, unlike some of its histologic mimics.

[Heterotopic tissue in the gastrointestinal tract]

Heterotopia of the gastrointestinal tract is a common finding. This is due to the complex embryogenesis and the relative ease to detect heterotopic tissue during endoscopy. The reason for biopsy is mostly to rule out neoplasms or to define specific causes of inflammation. Heterotopic tissue can occur in any location of the gastrointestinal tract. The most frequent are gastric heterotopia, pancreatic heterotopia, and heterotopia of Brunner's gland. On rare occasions, heterotopic tissue of salivary gland type as well as heterotopias of apocrine glands, thyroid, and prostatic tissue have been described. The most frequently involved organs are the small intestine, in particular the duodenum, the esophagus, and the stomach. Heterotopia of the large bowel occurs exclusively in the rectum. Most heterotopias do not cause symptoms and are easily diagnosed by biopsy and histology. However, depending on location, size, and the kind of underlying heterotopic tissue, they may cause significant complications, such as inflammation, ulceration and perforation, obstruction, intussusception, and severe life-threatening bleeding. Another rare but significant complication is neoplasia. Gastric heterotopias may give rise to pyloric gland adenomas within the bowel or rarely adenocarcinomas of the esophagus. Pancreatic heterotopia can be complicated by ductal type pancreatic adenocarcinomas, by acinus cell carcinomas, by intraductal papillary mucinous neoplasias, and also by endocrine tumors. The present paper summarizes our current knowledge about heterotopias in a topographic clinico-pathological manner.

Celiac Disease Associated with a Benign Granulomatous Mass Demonstrating Self-Regression after Initiation of a Gluten-Free Diet

Celiac disease is a chronic immune-mediated enteropathy in which dietary gluten induces an inflammatory reaction predominantly in the duodenum. Celiac disease is known to be associated with benign small bowel thickening and reactive lymphadenopathy that often regresses after the institution of a gluten-free diet. A 66-year-old male patient with celiac disease presented with abdominal pain and diarrheal illness. Computerized tomography of the abdomen revealed a duodenal mass. Endoscopic ultrasound-guided fine needle aspiration of the mass revealed bizarre stromal cells which represent a nonspecific tissue reaction to inflammation. This inflammatory mass regressed after the institution of a gluten-free diet. This case report describes a unique presentation of celiac disease in the form of a granulomatous self-regressing mass. Also, this is the first reported case of bizarre stromal cells found in association with celiac disease. In addition to lymphoma and small bowel adenocarcinoma, celiac disease can present with a benign inflammatory mass, which should be serially monitored for resolution with a gluten-free diet.

Small bowel intussusception in 2 adults caused by inflammatory polyps

Inflammatory fibroid polyps are rare, benign pseudotumors of the gastrointestinal tract of unknown etiology, which may rarely present as bowel intussusception and obstruction. The authors describe the clinical, radiologic, and pathologic features of 2 patients with ileal inflammatory fibroid polyps presenting as small bowel intussusception.

Identification of Signet Ring Cell Change in Colonic Subserosa in the Setting of Clostridium difficile Colitis

Signet ring cell change of intestinal epithelial cells is a rare but well-known mimicker of signet ring cell carcinoma and is often associated with ischemic and/or pseudomembranous colitis. Instead, signet ring cell change involving nonepithelial cells in the subserosa of the intestine is an extremely rare finding with only a single case report in the literature to date. We report a new case of benign signet ring cell change localized in the subserosa of the large bowel incidentally identified in a resection specimen for Clostridium difficile colitis mimicking a metastatic signet ring cell carcinoma. Based on the morphologic features and immunohistochemical profile, we propose that these signet ring cells may possibly represent modified/degenerated fat cells. Furthermore, we discuss how to differentiate benign signet ring cells from a signet ring cell carcinoma.

Inflammatory myofibroblastic tumor of the small-bowel mesentery: A case report of nonspecific clinical presentation and a review of the literature

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Inflammatory myofibroblastic tumors most frequently arises from the lung.

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Previously described in the literature as inflammatory pseudotumor, the current term for the condition is IMT.

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There are a very small number of IMT in the small intestine mesentery cases reported in the literature.

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The differential diagnosis of IMT includes reactive/reparative lesions and mesenchymal tumors of the gastrointestinal tract.

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The principal therapy in patients with IMT is surgical resection.

INTRODUCTION

Inflammatory myofibroblastic tumor (IMT) is a rare neoplasm of various anatomical sites, which is histopathologically characterized by spindle-shaped cells with myofibroblastic proliferation and inflammatory infiltration.

PRESENTATION OF CASE

In this case report, a 37-year-old man presented with nonspecific systemic symptoms, including abdominal pain and weakness, which was diagnosed by multislice computed tomography and ultrasonography. An 8 cm × 5 cm × 5 cm nodular gray-white firm noninfiltrative mass, which was well localized in the mesentery tissues of small bowel, was observed and the patient underwent surgical resection.

DISCUSSION

A review of the literature on IMT of the small-bowel mesentery yielded a small number of previously described cases. This tumor most frequently involves the lungs and arises most commonly in extrapulmonary locations such as the mesentery and omentum. The etiopathogenesis and the clinical course of the disease are unclear. The histological and clinical differential diagnosis of IMT also includes reactive processes and mesenchymal tumors of the gastrointestinal tract. Follow-up after surgical removal documented local recurrence and metastasis.

CONCLUSION

The preferred primary treatment is complete surgical excision, and patients require close clinicoradiological follow-up. In general, cases treated with complete surgical resection have a good prognosis.

Inflammatory pseudotumours of the oesophagus--histological and immunohistochemical findings

AIMS

Inflammatory oesophageal pseudotumours are rare lesions, thought to be reactive. Due to marked atypia of the stromal cells, these can be misdiagnosed as malignancies. The objective of this study was to characterize histological and immunohistochemical features of a series of inflammatory pseudotumours of the oesophagus.

METHODS AND RESULTS

We present 12 cases of inflammatory oesophageal pseudotumours, occurring in seven females and five males, with a mean age of 57.3 years. Clinical presentations were variable; dysphagia, abdominal pain and weight loss and upper gastrointestinal bleed. In a majority of the cases, nodules or masses in the distal oesophagus were identified at endoscopy. Microscopically, the lamina propria in all 12 cases contained inflammation and granulation tissue. Ten of 12 cases showed mucosal ulceration and 11 of 12 cases had acutely inflamed epithelium. Markedly atypical pleomorphic stromal cells with prominent nucleoli were identified in all 12 cases. Immunohistochemistry showed uniform positivity for vimentin in 11 of 11 cases, and two of seven cases demonstrated weak focal positivity for smooth muscle actin. The cells were negative for all other markers.

CONCLUSIONS

Reactive oesophageal lesions can show marked nuclear atypia in stromal fibroblasts/myofibroblasts, which are easily mistaken for malignancies. Pathologists must consider the diagnosis of an inflammatory pseudotumour if stromal atypia is present in an inflammatory background.

Supratentorial calcified pseudotumour: experience of a single institution and review of the literature

BACKGROUND

Calcified pseudotumours (CPTs) are rarely found in the central nervous system (CNS). Information on supratentorial CPT is limited. We add our experience treating three supratentorial CPTs. Clinical presentation, pathological findings and clinical course are discussed, and a literature review is provided.

METHOD

Between September 2011 and December 2012, three patients (age range 33-60 years) were diagnosed with symptomatic supratentorial CPTs, for which they underwent resection. Their clinical, radiological, and surgical data were retrospectively retrieved from their medical records and reported.

RESULTS

Symptoms at presentation included headache (n = 1), blurred vision (n = 1), and cognitive decline (n = 1). One tumour was in the left frontal lobe very close to the convexity surface, and the other two were in the midline adjacent to the corpus callosum. Radiological features included a calcified mass on computerised tomography (n = 3), a hypointense (n = 2) or hyperintense (n = 1) signal on T2 and a rim of enhancement with some non-homogenous lesional enhancement on T1-gadolinium (Gd) sequences on magnetic resonance imaging (n = 2). Two patients underwent gross total resection and had an uneventful postoperative course. The third underwent partial removal due to the tumour's adherence to adjacent vascular structures and suffered postoperative complications. On pathology, all lesions had low cellularity fibrovascular tissue mixed with lobules of a haematoxylinophilic, chondromyxoid-like matrix surrounded at its periphery by a variable layer of palisading spindle, epithelioid or multinucleated giant cells. All three CPTs had focal inflammatory infiltrates and variable degrees of metaplastic calcification and ossification.

CONCLUSIONS

Surgical removal is recommended for benign intracranial CPTs that are symptomatic, are associated with brain oedema, or show tumour growth. Stable and asymptomatic CPTs can be followed.

Bizarre Stromal Cells in the Esophagus: A New Case

Esophageal bizarre stromal cells (BSCs) represent an important diagnostic pitfall, since they can closely resemble a malignancy, thus leading to a significant overtreatment. We recently encountered a case in a healthy 38-year-old man, with a normal blood count, who underwent an upper gastrointestinal endoscopy during the follow-up of a grade I esophagitis and hiatus hernia. The endoscopy revealed an ulcerated sessile polyp that, on histology, consisted of a proliferation of round atypical discohesive cells, with a variable amount of cytoplasm, large nuclei, and prominent eosinophilic nucleoli. They were intermingled with many granulocytes and plump vessels, in a background of granulation tissue. Immunohistochemical stains with pan-cytokeratin, S100, and CD31 were negative and Ki67 stained only very few nuclei. At variance with other anatomical sites and despite the putative fibroblastic or myofibroblastic origin, BSCs in esophagus can have a striking epithelioid appearance, mimicking a carcinoma or a melanoma. Awareness of BSCs can prevent serious misdiagnoses.

Bizarre stromal cells in the esophagus: report of 2 cases and literature review

A significant mimicker of malignancy in the esophagus is the presence of atypical/bizarre stromal cells (BSCs). Two patients, a 60-year-old woman and a 59-year-old man, with esophageal polyps at the gastroesophageal junction showed highly atypical/bizarre cells in the polyps' stroma. BSCs were admixed with inflammatory cells and had large atypical nuclei, prominent nucleoli, and variably abundant amphophilic cytoplasm. Immunohistochemical studies showed that BSCs expressed vimentin whereas S-100, CD68, HMB45, CD45, Pan-cytokeratin, CK5/6, p63, CD10, EMA, MART-1, desmin, smooth muscle actin, CD31, CD34, and CMV were negative. Ki-67 showed low proliferative rate (less than 1% positivity). No evidence of intracellular mucin was found after histochemical stains (AB/PAS and mucicarmine). Follow-up endoscopic mucosal resection was available in both cases and showed benign esophageal mucosa and submucosa with disappearance, in one case, or marked decrease of BSCs. Esophageal BSCs reports in the literature invariably locate them in distal esophagus polyps or masses. Awareness of BSCs, of their location and associations, may help to prevent misdiagnosis of malignancy. The literature of esophageal BSCs is reviewed and the approach to this abnormality is discussed.

Polyps and polypoid lesions of the colon

CONTEXT

A significant portion of colorectal biopsies are performed for evaluation of polyps or polypoid lesions. Accurately identifying these lesions will promote better patient care.

OBJECTIVE

Review of the pathology of major colon polyps and polypoid lesions and highlight the most diagnostically useful features and their molecular biology.

DATA SOURCE

Review of recent literature.

CONCLUSIONS

Polypoid lesions of the colon can be thought of to be under 3 broad categories: syndromic, mesenchymal, and epithelial.

[Inflammatory esophageal polyp with bizarre stromal cells: possible diagnostic pitfall]

In the gastrointestinal tract an accurate diagnosis of tumor-like lesions can be challenging. In patients with reflux disease regenerative hyperplasia of esophageal squamous epithelium may show marked pleomorphism and atypia thereby simulating malignancy. Bizarre stromal cells are another diagnostic pitfall. We present the case of a 46-year-old patient with symptoms of reflux disease who was diagnosed with a benign inflammatory polyp at the distal end of the esophagus. Histology revealed bizarre cells within the stroma of the polyp characterized by nuclear hyperchromatism and enlargement. Mitoses were not observed. The atypical cells were positive for vimentin. The Ki67/MIB-1 proliferation rate was low. The morphology and etiology of bizarre stromal cells, including helpful features for differential diagnosis are thoroughly discussed.

Adult intussusception of the descending colon due to inflammatory myofibroblastic proliferation

We present a case of an asymptomatic 70-year-old man with intussusception of the descending colon due to inflammatory myofibroblastic proliferation. Abdominal ultrasound examination showed a hypoechoic mass, 32 × 19 mm in size, accompanied by intussusception in the descending colon, and power Doppler sonography detected blood flow signals in the mass. Computed tomography revealed a hypervascular lesion, which was confirmed by barium enema and colonoscopy. The surgically excised mass was histologically diagnosed as inflammatory myofibroblastic proliferation. Although intussusception due to inflammatory myofibroblastic proliferation is rare, it should be considered in cases of adult colonic intussusception.

Ileal Vanek's Tumor Mimicking Cecal Carcinoma

Inflammatory fibroid polyps or Vanek's tumors are rare benign pseudotumoral lesions with morphological characteristics similar to those of submucosal mesenchymal tumors. They have been described in the gastrointestinal tract, most frequently in the gastric antrum. We present a case of ileal Vanek's tumor associated with a raised carcinoembryonic antigen level and with radiological and endoscopic features mimicking cecal carcinoma.