Polypoid stromal lesions of the intestines

Calcified Fibrous Tumor of Jejunum: A Rare Case Report

A calcifying fibrous tumor (CFT) is a benign fibroblastic tumor of soft tissues occurring at all ages with no gender predilection. Earlier, it was called a pseudotumor. It may or may not present with symptoms. It can occur anywhere in the body - the most common sites are the stomach, pleura, and intestines. Our study is presented as a case of Intussusception in a young male with symptoms of pain, abdomen, and nausea. The patient underwent an excision of the tumor, and the tumor was examined histo-pathologically and immunohistochemically, showing spindle-shaped cells in dense collagenous tissue with mild inflammation. In this case, a study we are explaining the Clinical and morphological features of the CFT and how to differentiate it from other mesenchymal tumors.

NF1-Associated Inflammatory Polyp of the Colon: First Report of a Sporadic Case

"Juvenile-like (hyperplastic/inflammatory) mucosal polyp" is a term proposed for rare benign mesenchymal lesions of the gastro-intestinal tract so far reported only in patients with type 1 neurofibromatosis (NF1). We report here a first sporadic case of NF1-associated mucosal inflammatory polyp of the colon. The diagnosis was made in a 53-year old female patient with a large polypoid tumor of the cecum. The lesion was predominantly mucosal, made of fibroblast-like cells associated with inflammatory infiltrates rich in eosinophils and containing entrapped, distorted epithelial glands, responsible for the juvenile-like appearance. Whole exome sequencing showed a pathogenic variant of NF1. The patient had no evidence of NF1; no NF1 mutation was detected in normal tissues. Our observation may support the existence of juvenile-like inflammatory polyps associated with NF1 alterations, either germline or somatic. This justifies to test NF1 in difficult-to-classify gastrointestinal mesenchymal tumors.

Spindle cell proliferations of the sigmoid colon, rectum and anus: a review with emphasis on perineurioma

A wide range of spindle cell proliferations are found uncommonly in the sigmoid colon, rectum and anus. They usually present as polyps, and include reactive lesions and benign and malignant neoplasms which may be primary or metastatic. They are less frequently described in the literature compared to those in the upper gastrointestinal tract, and may be underdiagnosed. The widespread use of sigmoidoscopy in symptomatic patients and bowel cancer screening programmes means that histopathologists must be aware of, and adopt a logical approach to, diagnosing spindle cell proliferations in biopsy and polypectomy specimens. This is particularly relevant given the strong association of some mesenchymal polyps with hereditary cancer syndromes. This review article will focus on perineurioma and the recent debate in relation to its overlap with fibroblastic polyp. The clinical, endoscopic, histological and immunohistochemical features of spindle cell proliferations which should be considered in the differential diagnosis of perineurioma will be discussed. There is also a brief reference to malignant spindle cell tumours of diagnostic importance.

Benign epithelioid peripheral nerve sheath tumour arising in the rectum: A cytological and histological description

A 57-year old man presented with a 3.6 cm submucosal rectal cystic mass detected on colonoscopy and MRI. The lesion was deroofed, with rectal cyst fluid and cyst wall received for examination. Smears contained atypical cells occurring singly and in small aggregates, with epithelioid and spindled cells with hyperchromatic nuclei. Occasional cells exhibited intranuclear cytoplasmic inclusions. The concurrent histopathology specimen from the rectal cyst wall showed good correlation with the cytologic findings. The lesion was confined to the muscularis propria, with predominantly epithelioid cells and occasional spindled forms arranged in sheets, nests, and trabeculae with intervening fibrillary and fibrous stroma. Mitotic figures were scant, with no atypical mitoses or necrosis. An extensive immunohistochemical panel was performed, showing strong and diffuse nuclear and cytoplasmic staining with S100 and moderate to strong intensity nuclear staining with SOX10, in keeping with a benign epithelioid peripheral nerve sheath tumour. The patient remains well 3 years following diagnosis, and two subsequent biopsies at the site show no evidence of recurrent disease. We herein provide the first cytologic description of this lesion, with histopathologic correlation and a brief review of other differential diagnostic possibilities.

Colonic perineurioma (benign fibroblastic polyp): case report and review of the literature

BACKGROUND

Colorectal perineuriomas are uncommon benign mucosal-based proliferations of mesenchymal cells that express perineurial markers, often associated with colonic crypts displaying a serrated/hyperplastic architecture. The vast majority of cases arise distal to the splenic flexure and have been described as sessile polyps. Using molecular analysis, BRAF mutations have been demonstrated in the serrated crypt epithelium. We report a new case of perineurioma presenting as a pedunculated polyp in the transverse colon, with prominent hemosiderin deposits in the uninvolved lamina propria that separated the perineurial proliferation from the surface epithelium, a previously unreported histological finding. By using immunohistochemistry, we demonstrated the presence of BRAF V600E mutated protein in the serrated crypt epithelium. In addition, a review of the literature on colorectal perineurioma is provided.

CASE PRESENTATION

A 5 mm pedunculated polyp was removed from the transverse colon of a 42 year old man who presented with epigastric pain, weight loss and rectal bleeding. A proliferation of uniform plump spindled cells expanded the lamina propria and separated serrated colonic crypts. The epithelial component closely resembled microvesicular hyperplastic polyp. Immunohistochemical stains for epithelial membrane antigen (EMA), glucose transporter 1 (GLUT1) and collagen IV were positive in the stromal proliferation. A mutation-specific monoclonal antibody directed against BRAF V600E showed positive cytoplasmic staining in the serrated crypt epithelium but not in the perineurial proliferation. Conspicuous hemosiderin deposition was seen in the inflamed lamina propria between the perineurial proliferation and the surface epithelium.

CONCLUSION

Although the majority of colorectal perineuriomas occur in the sigmoid colon and rectum and are described as sessile polyps, colorectal perineurioma can present as a pedunculated polyp proximal to the splenic flexure as described in this case. Conspicuous hemosiderin deposition can be seen in the superficial lamina propria. BRAF mutations are limited to the serrated crypt epithelium.

Calcifying fibrous tumor of stomach: A case report

RATIONALE

Calcifying fibrous tumor (CFT) is a rare benign soft tissue mesenchymal neoplasm. Although the gastrointestinal (GI) tract is the most common predilection site of CFT, the clinicians, even including pathologist, generally consider it as GI stromal tumor (GIST) or other submucosal tumors such as schwannoma and leiomyoma.

PATIENT CONCERNS

A 55-year-old man presented with complaints of epigastric discomfort and abdominal distention for more than 1 year.

DIAGNOSES

On the basis of endoscopic and computed tomography examination, preliminary diagnosis was GIST.

INTERVENTIONS

Endoscopic submucosal dissection (ESD) surgery was performed to remove the gastric mass.

OUTCOMES

The histopathological examination revealed a gastric CFT.

LESSONS

We present a case of gastric CFT, which was misdiagnosed as GIST based on endoscopic and radiologic findings.

Cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal neoplasms occurring in the gastrointestinal tract

The purpose of the present review is to analyze the cytohistological and immunohistochemical characteristics of spindle-shaped mesenchymal gastrointestinal neoplams (MGNs), a group of unusual neoplastic conditions with different biological behavior. These tumors exhibit clinical pictures strictly related to the site of origin and dimensions, even if they appear generally with an intramural localization. This latter point may suggest an useful application of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), mainly followed by the cell-block procedure (CBP) in the differential diagnostic approach. First of all, we discuss the most common entity of MGNs represented by gastrointestinal stromal tumors (GISTs), analyzing the morphologic characteristics and stressing the strength of immunohistochemical algorithm for diagnostic purposes. Successively, we have reported the less common group of spindle-shaped MGNs comprehensive of those arising elsewhere the soft tissues, such as leiomyomas, leiomyosarcomas, schwannomas, inflammatory myofibroblastic tumor and intra-abdominal desmoid fibromatosis. Finally, very uncommon spindle-shaped MGNs, like clear cell, follicular dendritic cell, undifferentiated pleomorphic and radiation-induced sarcomas as well as spindle cell dedifferentiated liposarcomas, have been briefly mentioned.

Clinicopathologic study of calcifying fibrous tumor of the gastrointestinal tract: a case series

Calcifying fibrous tumor (CFT) is a rare benign mesenchymal lesion known to arise at multiple body sites that may clinically mimic other more aggressive lesions in the gastrointestinal (GI) tract. In this study we describe the clinicopathologic findings of 28 GI tract CFTs. Tumors predominantly arose in middle-aged adults with a slight female predominance. The most commonly involved sites were small bowel and colon, followed by stomach and appendix. Tumors ranged from 0.3 to 9.3 cm (median 1.4 cm), and submucosa was the most commonly involved layer. All tumors were well circumscribed and unencapsulated. Microscopically, tumors were hypocellular and composed of spindle cells with abundant, haphazardly arranged hyalinized collagen. No necrosis and less than one mitosis per 10 HPF were identified in all cases. Calcification was present in most (81%) of the cases. All cases had lymphoplasmacytic inflammatory infiltrates either scattered throughout the lesion with occasional perivascular conglomeration or in the form of lymphoid aggregates. A lymphoplasmacytic cuff was usually present (81%). Immunostains showed variable CD34 immunoreactivity and variable numbers of IgG4-positive plasma cells. The lesional cells were negative for DOG-1, ALK-1, S100, C-kit, Sox10, Melan A, HMB45, desmin, CK7, and CK20, and showed cytoplasmic staining for β-catenin. Follow-up information was available in 5 cases with no recurrences reported to date (mean follow-up, 3 years). CFT is a rare benign tumor that can occur in part of the GI tract and should be distinguished from other mesenchymal tumors due to its low risk of recurrence.