Inflammatory myofibroblastic tumors (inflammatory pseudotumors) of the gastrointestinal tract: how closely are they related to inflammatory fibroid polyps?

Inflammatory Myofibroblastic Tumor of the Sciatic Nerve Mimicking Lumbar Disc Herniation: A Diagnostic Challenge

Inflammatory myofibroblastic tumors (IMTs), which involve the proliferation of fibroblastic-myofibroblastic cells mixed with inflammatory infiltrates, are exceedingly rare in the extremities. There are no reported IMTs involving the sciatic nerve. This type of involvement may cause entrapment of the sciatic nerve, whose symptoms may mimic lumbar disc herniation (LDH), especially when it occurs in patients with lumbar degenerative disc disease. We describe the case of a 40-year-old male with lumbar degenerative disc disease accompanied by IMT involving the sciatic nerve whose symptoms mimicked LDH and posed a diagnostic challenge. We showed the course of the disease as well as the systematic imaging manifestations of IMTs involving the sciatic nerve and discussed their therapeutic management.

Non-gastrointestinal stromal tumor, mesenchymal neoplasms of the gastrointestinal tract: a review of tumor genetics, pathology, and cross-sectional imaging findings

There is a diverse group of non-gastrointestinal stromal tumor (GIST), mesenchymal neoplasms of the gastrointestinal (GI) tract that demonstrate characteristic pathology and histogenesis as well as variable imaging findings and biological behavior. Recent advancements in tumor genetics have unveiled specific abnormalities associated with certain tumors, influencing their molecular pathogenesis, biology, response to treatment, and prognosis. Notably, giant fibrovascular polyps of the esophagus, identified through MDM2 gene amplifications, are now classified as liposarcomas. Some tumors exhibit distinctive patterns of disease distribution. Glomus tumors and plexiform fibromyxomas exhibit a pronounced affinity for the gastric antrum. In contrast, smooth muscle tumors within the GI tract are predominantly found in the esophagus and colorectum, surpassing the incidence of GISTs in these locations. Surgical resection suffices for symptomatic benign tumors; multimodality treatment may be necessary for frank sarcomas. This article aims to elucidate the cross-sectional imaging findings associated with a wide spectrum of these tumors, providing insights that align with their histopathological features.

Large Inflammatory Myofibroblastic Tumor of the Esophagus: A Case Report and Literature Review

Inflammatory myofibroblastic tumor (IMT) is a rare tumor composed of myofibroblasts with inflammatory blood cell infiltration. It commonly occurs in the lungs and rarely in the esophagus. We herein report a valuable case of IMT originating in the esophagus. A 60-year-old Japanese woman with dysphagia had a large subepithelial lesion in the cervical esophagus, which was 15 cm in length. Surgical resection was performed to confirm the pathological diagnosis and improve the symptoms. The postoperative diagnosis was IMT composed of multiple nodules. There was no recurrence or metastasis within one year after surgery.

Gastrointestinal Tract Challenges: Chronic Inflammatory Fibroid Polyps Demystified

An inflammatory fibroid polyp (IFP), also known as Vanek's tumor, is an uncommon benign tumor typically found as a solitary, intraluminal polyp in the gastrointestinal (GI) tract. Chronic IFP is characterized by persistent or recurrent inflammatory features, distinct histopathological findings, and a potential for significant GI tract involvement. Typically, IFPs occur predominantly in the gastric antrum, small intestines, and recto-sigmoid colon. They initiate within the submucosal layer and extend into the lamina propria, resulting in a noticeable bulging of the mucosal layer. They may breach the mucosal barrier on rare occasions, leading to ulceration and bleeding. This ongoing bleeding can induce persistent blood loss and symptoms typical of hypovolemic shock. When of smaller size, these growths might be accidentally detected during an endoscopic examination. Conversely, if the lesions are sizable, they can prompt symptoms of obstruction like queasiness, retching, and abdominal discomfort. Here, we present a case of a 47-year-old female who underwent a screening colonoscopy and was found to have an IFP.

Infantile inflammatory myofibroblastic tumour of the sigmoid colon: a diagnostic dilemma

An inflammatory myofibroblastic tumour (IMT) is an uncommon neoplasm composed of inflammatory cells and myofibroblasts in a fibrous stroma. They are mostly seen in the lungs and rarely involve the gastrointestinal tract. An 8-month-old infant presented with a history of lower abdominal lump for 2 months. Her CT scan confirmed a large, lobulated mass in the retroperitoneum arising from the pelvis. The mass was found to be arising from the sigmoid colon on laparotomy which was excised. Histopathology showed a cellular tumour composed of spindle cells and inflammatory lymphocytic infiltrate. Immunohistochemistry revealed positive staining for anaplastic lymphoma kinase and smooth muscle actin, confirming the diagnosis of IMT. The patient is doing well at her 6-month follow-up. Ours is the youngest case of sigmoid IMT among the only other series of eight cases reported in the literature indicating its rarity.

Hepatic Inflammatory Pseudotumor-Focusing on Its Heterogeneity

Hepatic inflammatory pseudotumors (IPTs) are defined as benign, non-malignant, non-metastasizing tumors characterized by the presence of myofibroblastic spindle cells, hetorogenous populations of inflammatory cells, particularly plasma cells, lymphocytes and macrophages, as well as locations of fibrosis and necrosis without cellular anaplasia or atypical mitoses. Despite subsequent reports in the references, hepatic IPT remains difficult to diagnose; while posing major issues specifically for its differential diagnosis compared with that of other various benign diseases and malignant hepatic tumors. Histopathological findings are always a requisite for confirming the diagnosis, particularly given that the pathogenesis of IPT remains ambiguous to date. Hepatic IPT is a heterogeneous entity in terms of its clinical features, pathological findings, and pathogenesis. Once the diagnosis is confirmed, however, needless surgery such as wedge resection and lobectomy should be avoided. Here, we discuss the heterogeneity of hepatic IPT, its clinical features, pathological findings, and pathogenesis, and describe its differential diagnosis.

Larynx myofibroblastic tumor, a rare case report

Myofibroblastic tumors are extremely rare in the larynx, with just over 40 published cases. Despite being a benign tumor, it presents with a marked inflammatory character, local destruction, and the possibility of degeneration to malignant histological types with metastatic capacity. Anatomopathological differential diagnosis is fundamental in these cases.

Hepatic inflammatory myofibroblastic tumor: A case report

BACKGROUND

Hepatic inflammatory myofibroblastic tumor (HIMT) is a rare type of hepatic tumor. It is always misdiagnosed and mistreated because it is primarily found with no obvious specific manifestation, and its imaging findings are diverse.

CASE SUMMARY

Here, we report a case of HIMT that was initially diagnosed as liver malignancy but was confirmed as HIMT by histopathology after hepatectomy. Mostly, HIMTs are infiltrated with plasma cells and stain positively for anaplastic lymphoma kinase on immunohistochemistry as well as for some other kinases.

CONCLUSION

HIMT can be treated with single nonsteroidal anti-inflammatory drugs and without surgery when it is diagnosed accurately. Because the etiology of HIMT is unknown and the diagnosis is difficult, the pathogenesis and clinical process need to be further studied.

Jejunal Intussusception Secondary to a Large Inflammatory Fibroid Polyp: A Case Report and Discussion of Differential Diagnosis

Inflammatory fibroid polyp (IFP), initially considered a reactive process, is now recognized as a benign mesenchymal neoplasm of the gastrointestinal tract. We report a case of a 68-year-old woman with medically refractory Crohn disease that presented with intussusception requiring surgical intervention. The resection revealed a jejunal mass consisting of a submucosal proliferation of bland spindle cells in a fibrous stroma infiltrated by numerous eosinophils. By immunohistochemistry, the lesion was positive for vimentin and negative for desmin, smooth muscle actin (SMA), S-100, CD117, DOG1, ALK (D5F3), Melan-A, HMB-45, CD34, and STAT6. Ki-67 proliferative index was low (<1%). The mass was classified as IFP by its characteristic morphology and associated eosinophilia. IFP should be considered in the differential diagnosis of adults with intussusception or bowel obstruction. Definitive treatment typically requires surgical resection of the involved bowel segment.

Case Report: Ileo-Ileal Intussusception Secondary to Inflammatory Fibroid Polyp: A Rare Cause of Intestinal Obstruction

Introduction

Intussusception is a telescoping of a bowel segment into another and it can be a surgical urgency. Most adult intussusceptions arise from a lead point which can be benign or malignant. For this reason, intussusception in adults should undergo surgery. Here we describe a case of ileal inflammatory fibroid polyp (IFP), presenting with ileo-ileal intussusception and obstruction.

Case report

A 54-year-old Caucasian woman presented for acute abdominal pain. A radiography and a CT of the abdomen were performed, which showed signs of occlusion due to an ileo-ileal intussusception. An urgent laparoscopy was performed, the intussusception was extracorporeally reduced, the ileal segment involved was resected, and an ileo-ileal anastomosis was performed. The intussusception seemed to be caused by a 3-cm intra-mural lesion.

Discussion

Intussusception is a surgical concern. While most cases are idiopathic in children, 90% of adult intussusceptions are caused by underlying diseases. Therefore, intussusception in adults should undergo surgery. Radiology is necessary for the diagnosis: the CT scan helps localizing the lesion and shows pathognomonic signs. This case report analyzes an intussusception caused by an inflammatory fibroid polyp. Accurate diagnosis of IFP is only possible with histopathological examination, helped by immunohistochemistry. The differential diagnosis is important because some lesions are malignant.

Conclusion

We reported a case of intussusception caused by an IFP. The diagnosis was made with a CT scan together with intraoperative findings and histopathological examination, which excluded potential differential diagnoses. The patient underwent an explorative laparoscopy, with an ileal resection and anastomosis. Due to the risk of malignancy, surgery is mandatory.

Rare Finding of Inflammatory Fibroid Polyp of the Duodenum: A Complete Diagnostic and Pathological Workup

Inflammatory fibroid polyps (IFP) are solitary benign tumors rarely found in the gastrointestinal (GI) tract. Additionally, duodenal polyps are diagnosed incidentally. We present a case of a 51-year-old female admitted to the department with an initial diagnosis of duodenal polyp on gastroscopy, CT, and positron-emission tomography (PET). COVID-19 pandemics was the reason for delayed treatment which allowed the lesion to progress and almost double its size in an eight-month period. We performed conventional duodenotomy and excision of the polyp. Diseases like gastrointestinal stromal tumor (GIST), inflammatory myofibroblastic tumor, and inflammatory polyp of Crohn’s disease must be considered in the differential diagnosis of IFP because they could be observed in the same location.

Inflammatory myofibroblastic tumor successfully treated with metformin: A case report and review of literature

BACKGROUND

Inflammatory myofibroblastic tumor (IMT) is a distinct tumor with a low incidence rate, which can be diagnosed at any age with a predilection for children and adolescents. Although IMT is visible in any tissues and organs, it is more commonly found in the lungs. The clinical and radiological manifestations of IMT lack specificity, hence resulting in frequent misdiagnosis. Surgical resection is currently the main therapeutic approach for IMT. Only scarce cases of IMT treated with metformin have been reported. Here we report the case of an IMT patient with partial penile resection treated with metformin.

CASE SUMMARY

A 1-year-old boy was born with a shorter penis, and his foreskin could not be completely turned over. When he was 6 month old, a well-circumscribed mass on the glans was found, while it did not attract the attention of his parents. The mass gradually increased in size over time before he was admitted to the hospital, where physical examination was performed. It was revealed that the glans hidden behind the foreskin had a mass with a diameter of about 4 cm surrounding the penis. The mass appeared to be hard with a smooth surface and poor mobility. The two testicles examined at the bottom of the scrotum were revealed to have a normal size. Magnetic resonance imaging showed a tumor with rich blood supply encircling the cavernosum with a size of 3.5 cm × 2.1 cm × 2.0 cm. A thick urinary line was found without urine dripping, urgency, and urodynia. Surgical treatment was performed. During the operation, it was observed that the mass had surrounded and invaded the cavernosum without obvious boundaries, and that the tumor occupied about one-half of the penis cross-section as well as infiltrated more than one-half of the glans. In addition, the tumor had caused urethral invasion and anterior urethrostenosis. With the intention of keeping the glans and cavernosum, the tumor at the anterior urethra was partially removed, leaving about 30% of the tumor mass. Pathology analysis demonstrated that the tumor was rich in spindle cells with infiltration of inflammatory cells. Immuno-histochemistry analysis indicated that the cells were positive for CD4, CD99, Ki67, BCL2, and CD68, and negative for ALK, MyoG, S100, SOX10, PR, and EMA. Hence, the tumor was diagnosed as IMT. Metformin was prescribed for the patient after the operation, following which an oral dose of 7 mg/kg was given three times a day after meals. Three months later, it was observed that the remaining tumor had completely disappeared and that the urination process from the urethra opening had resumed normal. In addition, there were no side effects observed. There was also no tumor recurrence. The growth and development of the boy were unaffected as a result of the treatment.

CONCLUSION

The tumor was observed to have completely disappeared after treatment with metformin. Our finding is of great significance to facilitate future clinical treatment with IMT.

Gastric tumors in children: single-center study with emphasis on treatment of repeated recurrence

PURPOSE

Analysis of surgical management and survival of pediatric patients with gastric tumors treated at our institution.

METHODS

A retrospective study of patients with primary gastric tumors treated between 1993 and 2018 was conducted.

RESULTS

Eight patients, five girls and three boys, were diagnosed with gastric tumors at an average age of 10.4 years (1 day-15.4 years). Surgical management included Billroth type I procedure in five and tumor excision in three patients. Histology revealed gastrointestinal stromal tumor (GIST) in four patients and one of each of schwannoma, myofibroblastic tumor, hamartoma and teratoma. Microscopically clear margins were reported in six patients. Repeated local recurrence occurred in three patients (2 × GIST, 1 × myofibroblastic tumors) who consequently underwent three, four and six reoperations. One of these patients had liver metastases, which were managed with ligation of the hepatic arteries. This patient was also diagnosed with a lung hamartoma, which was treated with a lobectomy. Survival rate was 100% with a median follow-up of 8.6 years (7 months-25.5 years).

CONCLUSIONS

Gastric tumors are rare in children and represent a management challenge. Repeated recurrence of GISTs and myofibroblastic tumors remains frequent even after complete resection and may necessitate multiple surgeries, therefore patients require a lifelong follow-up.

Giant Ileocecal Inflammatory Fibroid Polyp: Unique Clinical Presentation

Inflammatory fibroid polyps (IFPs) are infrequent gastrointestinal tract benign neoplasms. They mostly occur in the stomach especially the antrum. Signs and symptoms depend on their anatomic location and lesion size. Lesion biopsies are very challenging for accurate diagnosis in these lesions. Histopathological examination of resected tissue along with immunohistochemical studies is the perfect way to confirm the final diagnosis. In this paper, the authors present an unusual case of IFP in a 23-year-old female patient presented to the emergency room (ER) with a picture of intestinal obstruction and severe abdominal pain. Her investigations revealed a huge mass located at the ileocecal valve, with overall features mimic gastrointestinal stromal tumor (GIST) clinical presentation. Surgical resection is considered the most commonly used treatment method. The overall prognosis is good with a low risk of recurrence.

Inflammatory myofibroblastic tumor of ileum with intussusception in adult

A 62-year-old man was referred to our department with suspected intussusception due to an ileal tumor. Tumor markers including soluble interleukin-2 receptor were not elevated. Contrast-enhanced computed tomography and color Doppler ultrasonography showed a distinct ileal tumor without intratumoral blood flow or surrounding lymphadenopathies. Retrograde single-balloon enteroscopy revealed a submucosal tumor in the ileum that was hard and ulcerated. Partial intestinal resection was performed, and the lesion was diagnosed as an inflammatory myofibroblastic tumor. The patient had no recurrence over 2 years without additional treatment after surgery. This rare tumor should be kept in mind as a cause of ileal intussusception in adult and a multidisciplinary approach is vital to characterize it.

A large inflammatory fibroid polyp of the rectum removed by transanal excision

Inflammatory fibroid polyps (IFP) are rare benign lesions arising from the submucosa of the gastrointestinal tract, most commonly found in the stomach and small intestine. IFPs are very rarely found in the rectum, with only a few reported cases, and their presentation is quite varied. The patient is a 53 year old male who underwent routine screening colonoscopy, during which a lobular mass of the proximal rectum was discovered. The patient subsequently underwent an endoscopic ultrasound (EUS) with fine needle aspiration (FNA) biopsy. Pathology displayed scant spindle cells with benign glandular epithelium suspicious for a spindle cell neoplasm. The mass was excised transanally. The morphological and immunohistochemical findings supported the diagnosis of inflammatory fibroid polyp. Although this is not a malignant tumor, the treatment and surveillance guidelines have not been determined and there is no standard of care.

Inflammatory myofibroblastic tumour of the jaw: A rare presentation

Inflammatory Myofibroblastic Tumour (IMT) is a rare entity of unknown aetiology and pathogenesis. It was initially described in the lung, although there have been reported cases affecting extra-pulmonary sites. The aetiology of IMT remains unclear, with current evidence suggesting that IMTs are neoplastic processes resulting from chromosomal translocations that often cause an overexpression of ALK tyrosine kinase. Histologically, a variably cellular myxoid morphology is common in these tumours, with the presence of inflammatory cell infiltrate. Clinically, symptoms are non-specific, although the presence of a swelling is frequently reported. Imaging studies are not very useful in the diagnosis, as they only describe the presence of a mass, and do not provide a definitive diagnosis. This article presents a case, of Inflammatory Myofibroblastic Tumour of the jaw, in a male patient aged 16 years.

Double amplifications of CDK4 and MDM2 in a gastric inflammatory myofibroblastic tumor mimicking cancer with local invasion of the spleen and diaphragm

Inflammatory myofibroblastic tumor (IMT) is currently recognized as an intermediate mesenchymal neoplasm. It can arise anywhere in the body, but it is particularly common in the lungs. Gastric IMT is very rare in adults. In this study, we report a case of a 68-year-old woman with IMT in the gastric cardia, with invasion into the spleen and diaphragm. Because of its location and aggressive clinical features, it was first mistaken for gastric cancer. However, pathology and immunohistochemistry were used to finally confirm the diagnosis of IMT after total resection of the tumor and spleen and partial resection of the diaphragm. In order to provide better understanding of this rare tumor, targeted next-generation sequencing (NGS) and IHC were performed to assess genetic and protein abnormalities of the tumor. Both IHC and NGS were found to be negative for ALK or other gene fusions. However, double amplification of CDK4 and MDM2 were found by NGS, and IHC also found CDK4 and MDM2 to be positive. To the best of our knowledge, this is the first gastric IMT report to show double invasion of the spleen and the diaphragm, and double amplification of CDK4 and MDM2 in IMT are also reported for the first time. This genomic aberration with protein overexpression is the most likely tumorigenic driver of this rare and aggressive tumor.

Invasive inflammatory fibroid polyp of the stomach: a case report and literature review

Background

Inflammatory fibroid polyps (IFPs) are rare mesenchymal lesions that affect the gastrointestinal tract. IFPs are generally considered benign, noninvasive lesions; however, we report a case of an invasive gastric IFP. To the best of our knowledge, this is only the second case report of an invasive gastric IFP.

Case presentation

A 62-year-old woman presented with complaints of epigastric pain and vomiting. Computed tomography showed a 27-mm, hyper-enhancing tumor in the prepyloric antrum. Upper endoscopy also showed a submucosal tumor causing subtotal obstruction of the gastric outlet. Because a gastrointestinal stromal tumor was suspected, distal gastrectomy was performed. Histopathological examination revealed spindle cell proliferation in the submucosal layer. The spindle cells had invaded the muscularis propria layer and extended to the subserosal layer. The tumor was finally diagnosed as an IFP based on immunohistochemical findings. No mutations were identified in the platelet-derived growth factor receptor alpha (PDGFRA) gene via molecular genetic analysis.

Discussion and conclusions

After the discovery that IFPs often harbor PDGFRA mutations, these growths have been considered neoplastic lesions rather than reactive lesions. Based on the present case, IFPs might be considered not only neoplastic but also potentially invasive lesions.

Inflammatory fibroid polyp of the gastric antrum presenting as hypovolemic shock: Case report and literature review

Inflammatory fibroid polyps (IFP) are an extremely rare entity that arise within the submucosa of the gastrointestinal tract, and represent less than 0.1% of all gastric polyps. They are most commonly localized to the gastric antrum, small intestines and recto-sigmoid colon. IFPs are most commonly found incidentally upon endoscopic evaluation in the absence of symptoms. Presenting symptoms depend on the location of the tumor, although polyps located in the stomach most commonly present with epigastric pain and early satiety. Classic histologic features include perivascular onion skinning of spindle cells with an abundance of eosinophilic infiltration. The prompt diagnosis and management of IFP is essential due to its underlying risk for intussusception, outlet obstruction and acute hemorrhage. In addition, recent evidence has shown that IFP is driven by an activating mutation in the platelet derived growth factor receptor alpha (PDGFRA) gene, suggesting a neoplastic etiology. Herein, we discuss a case of a 65-year-old woman with an inflammatory fibroid polyp of the gastric antrum who initially presented with early hypovolemic shock and melena. Diagnosis was made by endoscopic visualization, biopsy and immunohistochemical analysis.

Atypical Presentation of Intestinal Intussusception Caused by Insidious Inflammatory Myofibroblastic Tumor of the Bowel Wall

Introduction:

Inflammatory myofibroblastic tumor (IMT) is a rare but real tumor, which is histologically characterized by myofibroblastic spindle cells proliferation with inflammatory infiltrate. The lung is the most common affected organ, and extrapulmonary IMTs are less common. However, IMT seldom presents in the gastrointestinal tract, and intussusception is a rare complication of this tumor.

Case presentation:

We documented this rare case of a 12-year-old Chinese girl presenting with abdominal pain. The clinical and radiologic impression was bowel intussusception and bowel obstruction. No sign of abdominal mass was found before surgery, neither physical examination nor radiologic images. Operative findings revealed intestinal intussusception secondary to a little mass. Histopathlogic evaluation of this mass revealed IMT.

Conclusion:

In conclusion, IMT may present with bowel intussusception. However, at the intestinal location, the tumor may be found as an abdominal mass or may be insidious; hence, detailed history, physical examination, and imaging studies are necessary for early recognition and diagnosis.

A case report of tracheal inflammatory myofibroblastic tumor in a 34-week pregnant woman misdiagnosed with asthma

RATIONALE

Inflammatory myofibroblastic tumor (IMT) is an uncommon neoplastic entity with a tendency of local recurrence and a low risk of distant metastasis. Involvement of trachea is extremely rare.

PATIENT CONCERNS

A 34-week pregnant woman previously diagnosed with asthma for 2 months was admitted with persistent wheezing and hemoptysis. A computed tomography scan and bronchoscopy revealed a gigantic polyp in the trachea.

DIAGNOSES

Tracheal inflammatory myofibroblastic tumor.

INTERVENTIONS

The mass was removed with an electrocautery snare and identified histologically as an IMT. Further immunochemical staining showed strong positive staining for smooth muscle actin and platelet-derived growth factor receptor α (PDGFRA), weak positive staining for caldesmon, and negative staining for anaplastic lymphoma kinase (ALK)1, desmin, S-100, and CD34. The tracheal IMT strongly expressed estrogen receptor-α (ER-α), which indicated that the development of this rare IMT might have been associated with hormone fluctuations that occurred during the pregnancy.

OUTCOMES

Follow-up and histological analyses revealed no evidence of recurrence and metastasis.

LESSONS

This report describes an extremely rare case of a tracheal IMT that presented a diagnostic dilemma for the clinician and the pathologist. Tracheal IMT is a challenge for the clinician in diagnosis due to the nonspecific clinical presentation. Histology and immunohistochemistry are required to reach an accurate diagnosis of IMT.

Inflammatory myofibroblastic tumor in the head of the pancreas with anorexia and vomiting in a 69-year-old man: A case report

Inflammatory myofibroblastic tumor (IMT) is a rare condition of unclear etiology that is commonly observed in the lung but rarely in the pancreas. WHO classified IMT as a potentially malignant or aggressive tumor. In the present report, the case of a 69-year-old male patient with an IMT in the head of the pancreas, who experienced anorexia, nausea and vomiting, is presented. The patient's clinical symptoms were nonspecific, and the imaging findings revealed a hypovascularized pancreatic mass with stenosis of the descending duodenum. The electronic endoscopy findings revealed protruding lesions in the duodenal bulb and the descending duodenum. Biopsies of the mass were conducted with an electronic endoscope, but were not diagnostic. Subsequent duodenopancreatectomy aided in determining a pathological diagnosis of IMT, based on the histology and immunohistochemistry results. The patient experienced a recovery without further incident, as observed during a regular follow-up 3 years later. IMT in the head of the pancreas is rare, particularly in adults. In the present study, an extremely rare case of IMT involving the head of the pancreas in an adult patient is presented, and the therapeutic options for this condition are discussed.

Locally infiltrative inflammatory fibroid polyp of the ileum: report of a case showing transmural proliferation

Morphologically, an inflammatory fibroid polyp (IFP) is usually centred in the submucosa. Extension of an IFP to the subserosa with destruction of the muscularis propria is exceedingly rare. Herein, we describe a 70-year-old woman who presented with right lower abdominal pain but was finally diagnosed with an IFP. Contrast-enhanced computed tomography revealed a target-like structure with a hypovascular mass at the leading edge, which was consistent with intussusception due to a tumour. Following surgery, the resected specimen displayed a mass measuring 4 × 3 × 3 cm that was protruding into the lumen. Microscopically, the mass was centred in the submucosa, extending up to the mucosal surface and down to the subserosa and serosa. The muscularis mucosae and muscularis propria were destroyed focally. A PDGFRA gene mutation in exon 2 (1837_1851 del) that was found in this case, as well as a highly infiltrative growth pattern, strongly supported the neoplastic nature of IFP.

Remission of ALK-negative primary pulmonary inflammatory myofibroblastic tumor on treatment with clarithromycin: A case report and review of the literature

Inflammatory myofibroblastic tumors (IMTs) belong to an intermediate group of soft-tissue tumors, they are relatively rare but exhibit a wide range of pathologies, from benign to malignant. At present, no standard treatment has been established, however, it is known to be important to determine the grade of malignancy of the tumor, prior to treatment. The present study reports a 73-year-old female patient with no clinical manifestations, who, when examined radiographically at a health check exhibited bilateral thoracic infiltrative shadows and nodular shadows by chest CT. A metastatic tumor or an organizing pneumonia were suspected. Blood examination showed no abnormal findings, and a pathological diagnosis of IMT was given from the histological findings of the tissue extracted by video-assisted thoracic surgery. Histological analysis established the lack of expression of anaplastic lymphoma kinase (ALK1) and immunoglobulin subtype G4 (IgG4). Alteration of the radiological shadows was observed over several weeks, and after concluding that chronic inflammation was worsening the patient's condition, clarithromycin was administered as a long-term macrolide therapy. The IMT decreased in size, and eight months later it had almost resolved. The patient was last reported to be maintaining a stable condition with no relapse. Some IMT cases have malignant pathology, and should be carefully followed-up. However, in the present case, where the IMT is both ALK1-negative and IgG4-negative, its biological immune responsiveness appears to differ from positive cases, and an inflammatory response was predominant. Clarithromycin, has immunomodulatory and anti-inflammatory effects and appeared to be effective in treating the IMT of the patient in the present study.

Co-existence of acute appendicitis and inflammatory myofibroblastic tumor of the small intestine: A case report

INTRODUCTION

Inflammatory myofibroblastic tumor as a rare neoplastic lesion is seen most commonly in the pulmonary system. Beside the presence of limited number of inflammatory myofibroblastic tumors of the gastrointestinal tract in the literature, co-existence with acute appendicitis has not been reported before.

PRESENTATION OF CASE

A 27-year-old woman admitted to emergency department with acute abdominal pain at the right lower quadrant. The initial diagnosis was as acute appendicitis. Intraoperatively, a mass with a diameter of almost 5 cm originated from the distal ileal segments neighboring the appendix was seen. The patient was managed by segmental resection of the small intestine including the mass with appendectomy. Histologically, there were bundles of spindle cells accompanied by lymphoplasmocytic infiltration. The immunohistochemical studies showed that tumor cells were positive for smooth muscle actin, vimentin, perinuclear activity for anaplastic lymphoma kinase and CD 68. The final pathologic diagnosis was inflammatory myofibroblastic tumor.

DISCUSSION

Concomitant resection of tumoral lesions detected in the neighbor intestinal segments during appendectomy should be considered to diagnose and treat. For the diagnosis of inflammatory myofibroblastic tumor, immunohistochemistry pattern including positivity for actin, vimentin, CD 68 and anaplastic lymphoma kinase plays a crucial role. Therefore, detailed immunohistochemistry analysis should be performed in suspicious cases.

CONCLUSION

Coexistence of inflammatory myofibroblastic tumor located in the gastrointestinal system with acute appendicitis is a rare event. Complete surgical excision should be regarded as the mainstay of the treatment. Long-term follow up with serial imaging techniques is recommended.

Inflammatory myofibroblastic tumor of the thigh: presentation of a rare case and review of the literature

Inflammatory myofibroblastic tumors are uncommon neoplasms; presentation of these tumors in the lower extremities is extremely rare. We present a case of a 47-year-old male with fever, fatigue, and a slow-growing thigh mass. The inflammatory markers were elevated and the MR images showed a well-defined intermuscular lesion with mild heterogeneous enhancement. The lesion was excised and histologic examination was consistent with an inflammatory myofibroblastic tumor. No adjuvant therapy was needed and the patient remained asymptomatic with no evidence of tumor recurrence during the 2 years of follow-up.

Clinical, endoscopic and pathologic features of inflammatory fibroid polyps of the digestive system

AIM: To investigate the clinical, endoscopic and pathologic features, as well as differential diagnosis of gastrointestinal inflammatory fibroid polys (IFPs).

METHODS: The clinical data for 16 cases of IFPs were analyzed. The findings of endoscopy, endoscopic ultrasound, and histopathology were reviewed. Immunohistochemistry studies for Vimentin, CD34, CD117, discovered on GIST-1 (DOG-1), smooth muscle actin (SMA), S-100, and Desmin and cytokeratin (CK) were performed.

RESULTS: IFPs were mainly found in adults aged 40-60 years (56.25%), slightly more frequently in women. IFPs occurred mainly in the stomach (56.25%), small bowel (25%), and colon (18.75%), with the antrum being the most common place. The tumor might present as a polyp, submucosal mass or neoplasm-like mass. Endoscopic ultrasound showed hypoechoic lesions in the third or the second sonographic layer of the gastric wall but without involving the fourth layer, and the margin was poorly circumscribed. Histopathology showed that the tumor was mainly located in the submucosa and could invade the mucosa, but not the muscle layer. Microscopically, the main tumor components were fibroblast-like spindle cells, vascular and polymorphic inflammatory cells, usually dominant by eosinophils. The specific pathologic findings included eosinophils and concentric fibroblast-like spindle cells with an 'onion-skin'-like appearance around vessels. Immunohistochemical staining of the spindle cells of IFPs showed 100% positivity for vimentin and 87.5% positivity for CD34. Treatments for IFPs included surgery and endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR).

CONCLUSION: There are similar patterns for patient age and tumor location in IFPs. Endoscopy and endoscopic ultrasound can provide specific findings. The histopathological and immunohistochemical characteristics are useful for accurately diagnosing IFPs and differential diagnosis of the tumors occurring in the submucosa.

Endoscopic diagnosis and treatment of inflammatory fibroid polyps

AIM: To investigate the clinical manifestations, endoscopic and ultrasonographic features, and endoscopic therapy of gastric inflammatory fibroid polyps (IFPs).

METHODS: A total of 13 patients with IFPs treated at our center were collected between January 2007 January and April 2014. The clinical data for these patients were reviewed. All patients underwent digestive endoscopy, and 5 patients whose lesions were located at the antrum underwent endoscopic ultrasonography before therapy. Therapeutic methods were selected based on endoscopic morphology of the lesion.

RESULTS: IFPs had a modest female predominance (8 women and 5 men), with the majority of patients (11) being more than 50 years. Involved sites included the stomach (10), ileum (2), and colon (1). The tumors ranged in size from 6-60 mm (mean, 21.62 mm). Endoscopic features of the 13 lesions were submucosal tumors (7), polyps (3) and neoplasms (3). All lesions were located in the second (2) or third (3) sonographic layer of the antrum without involvement of the fourth layer. Endoscopic ultrasonographic features were hypoechoic/homogeneous echo pattern and unclear boundary. Four patients underwent endoscopic mucosal resection (EMR), 6 underwent endoscopic submucosal dissection (ESD) and 3 partial gastrointestinalresection. All were confirmed histologically as IFPs.

CONCLUSION: IFPs can occur throughout the gastrointestinal tract, commonly in the antrum. Understanding the characteristic digestive endoscopy and EUS features of IFP scan be helpful to IFP diagnosis. Treatmentby EMR or ESD iseffective and safe.

An unusual presentation of an inflammatory fibroid polyp of the ileum: A case report

Inflammatory fibroid polyps (IFP) are rare, benign lesions of the gastrointestinal tract. Recent molecular studies of IFPs identified platelet-derived growth factor receptor α (PDGFRA)-activating mutations, suggesting possible neoplastic qualities to IFPs. IFPs originate from the submucosa and often extend into the overlying mucosa. Although certain IFPs infiltrate the muscularis propria focally, disruption of the muscularis propria and penetration into the subserosa is extremely rare. The current study presents an unusual case of an ileal IFP. A 48-year-old female visited the Department of Surgery, Chonbuk National University Hospital (Jeonju, Republic of Korea) due to abdominal pain. Radiological study demonstrated an ileocecal-type intussusception due to a luminal polypoid mass of the ileum. The excised tumor consisted of haphazardly arranged epithelioid and spindled cells in a fibromyxoid stroma, with an abundant vascular network, accompanied by an inflammatory reaction predominantly composed of eosinophilic infiltrates. The infiltrating tumor cells disrupted the muscularis mucosa above the tumor cells and the muscularis propria below the tumor cells, and extended into the subserosa. Immunohistochemically, the tumor cells were positive for vimentin and cluster of differentiation 34, while they were negative for keratin, PDGFRA, smooth muscle actin, desmin, S-100 protein, DOG-1 and c-kit. Sequencing analysis of c-kit exons 9, 11, 13 and 17, and PDGFRA exons 12 and 18 indicated a wild-type status. The patient has remained well for 12 months after surgery without further treatment, with no recurrence of the tumor. Although spread of IFP under the muscularis propria is rare, identification of similar cases and further study will enhance our understanding of the nature of this tumor.

Follicular Dendritic Cell Sarcoma of the Inflammatory Pseudotumor-like Variant Presenting as a Colonic Polyp

Follicular dendritic cell (FDC) sarcoma is rare and is classified either as conventional type or inflammatory pseudotumor (IPT)-like variant. Extranodal presentation is uncommon and nearly all gastrointestinal FDC tumors are of the conventional type. IPT-like variant tumors occur almost exclusively in the liver and spleen and are consistently associated with Epstein-Barr virus (EBV). Here we report the case of a 78-year-old woman with an IPT-like FDC sarcoma presenting as a pedunculated colonic polyp. Histologically, scanty atypical ovoid to spindle cells were mixed with a background of florid lymphoplasmacytic infiltrate, which led to an initial misdiagnosis of pseudolymphoma. These atypical cells expressed CD21, CD23, CD35, and D2-40, and were positive for EBV by in situ hybridization, confirming the diagnosis. The patient was free of disease five months after polypectomy without adjuvant therapy. Although extremely rare, the differential diagnosis for colonic polyp should include FDC sarcoma to avoid an erroneous diagnosis. A review of the 24 cases of IPT-like FDC sarcoma reported in the literature reveal that this tumor occurs predominantly in females with a predilection for liver and spleen, and has a strong association with EBV.

Mesenchymal Tumors of the Gastrointestinal Tract Other than GIST

Mesenchymal tumors involve the gastrointestinal (GI) tract more frequently than other visceral organs. Many such tumors are small, and are benign and increasingly being detected incidentally during colonoscopic screening. Some tumors show distinctive features at this site, such as schwannoma and clear cell sarcoma-like tumor of the GI tract. Without knowledge of these features, recognition of these tumor types can be difficult. This reviews addresses recent developments and diagnostic features of mesenchymal tumors of the GI tract other than gastrointestinal stromal tumor (GIST).

Inflammatory fibroid polyp of rectum mimicking rectal cancer

Inflammatory fibroid polyps (IFPs) are rare benign tumors of the rectum. Mutation and activating platelet-derived growth factor receptor alpha (PDGFRA) contribute to tumor development. We present a case of IFPs in the middle rectum that mimic rectal cancer. A 65-year-old woman presented with the symptom of fresh blood in the stool and body weight loss of 6 kg in the preceding 3 weeks. A rectal polypoid tumor was noted upon digital examination. Sigmoidoscopy showed a middle rectal tumor measuring 3 × 2.7 cm with obstruction. Computed tomography (CT) scans of the abdomen showed a rectal tumor that had invaded the sacral bone and was associated with four enlarged lymph nodes greater than 1 cm. The radiological report suggested a diagnosis of rectal cancer with lymph node metastases. To remove the obstruction, the patient was initially treated with excision of the tumor and loop sigmoidal colostomy to the abdomen wall. Total mesorectal resection of rectal and sacral tumor followed 10 days later. Histopathological examination of the rectal and sacral tumor showed proliferation of vessels, fibroblast-like spindle cells, and mixed inflammatory cells, including the plasma cells and eosinophils. The spindle cells were diffusely positive to PDGFRA and were focal positive to CD34 and smooth muscle actin. Based on histopathological and immunohistochemical findings, the diagnosis of IFP is indicated. This was the first reported case of IFPs of the rectum presenting with lymph node enlargement and attachment to the sacrum mimicking rectal cancer.

Primary inflammatory myofibroblastic tumor of the breast with rapid recurrence and metastasis: A case report

Primary inflammatory myofibroblastic tumor (IMT) of the breast is extremely rare; only 19 cases have been reported in the English literature. In the present study, we present a case of IMT in a 56-year-old female patient who was admitted to our hospital due to a mass found in her right breast. Mammogram and ultrasound revealed a well-circumscribed mass and surgery was performed. Histopathologically, the lesion was composed of spindle and inflammatory cells, including plasma cells and lymphocytes. Mitotic figures were not observed. Immunohistochemically, the tumor cells were positive for SM-actin, anaplastic lymphoma kinase (ALK) and vimentin and focal positive for desmin, but negative for NSE, S-100, CD117, CD34, NF, CD21, CD35 and CD68. Thus, we made a diagnosis of IMT and advised regular follow-up. However, the patient had local recurrence and metastasis to the left groin area 3, 7 and 10 months after the initial surgery. Notably, the histopathological characteristics of the recurrent and metastatic foci were similar to those of the initial specimen, but mitotic figures were clearly observed. Thus, we conclude that IMT shows occasionally malignant biological behavior although it is a neoplasm of intermediate biological potential that frequently recurs and rarely metastasizes. We advise that clinical physicians should regularly follow up patients after focal resection for IMT.

Inflammatory Fibroid Polyp in the Duodenum of a Common Marmoset (Callithrix jacchus)

A 32-month-old male common marmoset had a firm and white-colored mass in the duodenal wall. The cut surface was smooth and grayish white in color. Histologically, the mass consisted of a proliferation of spindle cells with an oval to spindle-shaped nucleus and scant eosinophilic cytoplasm in a loose myxoid or fibrotic background. Most of the lesion displayed no specific growth pattern whereas some of the cells concentrated around the vessels and created an onion-bulb structure. Additionally, marked inflammatory cellular infiltration, mainly eosinophils, was observed throughout the lesion. Immunohistochemically, the spindle cells were positive for vimentin, α-smooth muscle actin, fascin, and cyclin D1, and negative for S-100, factor VIII–related antigen, and c-kit. These histological and immunohistochemical features did not meet any differential diagnoses such as gastrointestinal stromal tumor, inflammatory myofibroblastic tumor, solitary fibrous tumor/hemangiopericytoma, smooth muscle tumor, schwannoma, and hemangiosarcoma. Collectively, the authors diagnosed the mass as a lesion that corresponded to an inflammatory fibroid polyp (IFP) in humans. IFP is defined as a mesenchymal proliferation composed of spindle stromal cells, small blood vessels, and inflammatory cells, particularly eosinophils, and is currently classified as a nonneoplastic lesion. To the best of our knowledge, this is the first case of spontaneous IFP in nonhuman primates.

Rare gastric inflammatory myofibroblastic tumor in an adult woman: a case report with review of the literature

Inflammatory myofibroblastic tumor (IMT) of the stomach is extremely rare and its prognosis is unpredictable. We present a 37-year-old woman with a gastric IMT. She presented epigastric pain since 2 months, anemia and weight loss associated. Physical examination showed cutaneous pallor and mild abdominal tenderness in the epigastrium. Abdominal ultrasonography showed a tumor near the pancreas and the CT scan revealed that the lesion was arising from the stomach. Upper endoscopy showed a submucosal lesion of approximately 7.5 cm located in the posterior wall of the gastric body such as a gastrointestinal stromal tumor (GIST). The patient underwent a subtotal gastrectomy and Billroth I reconstruction. The histopathological and immunohistochemical analysis revealed an IMT that originated from the gastric wall.

An inflammatory fibroid polyp in the hepatic flexure of the colon treated with argon plasma coagulation, endoscopic clipping and polypectomy

Inflammatory fibroid polyp (IFP) is a rare benign polypoid lesion of the gastrointestinal tract. Most IFPs occur in the stomach and colonic occurrence is very rare. Histologically IFP is characterized by a mixture of numerous small vessels, fibroblasts and edematous connective tissue associated with marked inflammatory infiltration by eosinophils. We present a rare case of a pedunculated IFP in the hepatic flexure of the colon treated successfully with a combination of argon plasma coagulation, endoclipping and polypectomy. A 74-year-old asymptomatic female underwent a screening colonoscopy in our hospital. A 12-mm pedunculated polyp was found at the hepatic flexure of the colon. After saline injection, we attempted to remove the polyp with a hot snare. However the polyp stalk was extremely difficult to resect despite several attempts with the hot snare. We placed an endoclip at the base of the stalk and then applied argon plasma coagulation at 1.0 l/min and 40 W. After these measures we were able to resect the stalk and the polyp was retrieved. Histologically the polyp was located in the submucosa of the gastrointestinal tract. Proliferation of spindle cells and infiltration of inflammatory cells such as plasma cells and eosinophils were observed. The spindle cells were positive for CD34 and S100 but negative for c-kit and muscle markers. These findings are consistent with a histopathological diagnosis of IFP.

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.

Abdominal inflammatory myofibroblastic tumor a clinicopathologic study with reappraisal of biologic behavior

BACKGROUND AND PURPOSE

Inflammatory myofibroblastic tumor (IMT) is a proliferative lesion of controversial nosology and uncertain prognosis. In an attempt to acquire further understanding of pathogenesis and biologic behavior, we surveyed abdominal IMTs managed over the last 12 years at a single institution.

METHODS

Intra-abdominal IMTs treated between 1995 and 2007 were reviewed concerning demographic, clinical, and pathologic features as well as therapeutic management and outcome. All specimens were reevaluated by histologic examination and immunohistochemistry.

RESULTS

There were 7 patients (4 males; age range, 28 days to 14 years). Five lesions were located in alimentary tract: 1 gastric presenting with bleeding, 1 hepatic presenting with a thoracic wall mass, 1 pancreatic and 2 colonic presenting with obstructive symptoms. One splenic IMT was found incidentally. The remaining case arose from the adrenal gland and presented with a palpable mass. The gastric and adrenal IMTs had evidence of a previous or concomitant infectious setting. Five lesions were excised. The pancreatic IMT underwent a drainage procedure followed by steroid administration, and the hepatic lesion received antibiotics. Histopathology revealed characteristic findings of IMT. Expression of anaplastic lymphoma kinase was negative in all cases. At a median follow-up of 6 years (range, 3-15), all children were asymptomatic with no recurrences. The hepatic and pancreatic IMT displayed complete and near total regression, respectively.

CONCLUSION

A benign behavior of abdominal IMTs was observed even in patients not undergoing surgical excision. Although IMT remains a surgical disease, a conservative approach may be reasonable in select cases.

Comparison of morphological, immunohistochemical, and molecular genetic features of inflammatory fibroid polyps (Vanek's tumors)

Vanek's tumor (inflammatory fibroid polyp) is a rare benign lesion occurring throughout the digestive tract. Histologically, two patterns can be recognized. Classical Vanek's tumor contains concentric formations of proliferating spindle cells which are CD34 positive. Atypical, inflammatory pseudotumor-like Vanek's tumor lacks concentric formations and is CD34 negative. Recently, mutations in platelet-derived growth factor receptor alpha (PDGFRA) were reported in gastric and small intestinal Vanek's tumors. In this study, KIT exons 9, 11, 13, and 17, PDGFRA exons 12, 14, and 18, and a part of exon 15 BRAF for point mutation V600E were screened in 23 cases of Vanek's tumor, both classical (n = 16) and inflammatory pseudotumor-like (n = 7). No mutations in all analyzed exons of KIT and BRAF and in exon 14 of PDGFRA were detected. Six Vanek's tumors harbored activating mutations in PDGFRA exons 12 (n = 5) and 18 (n = 1) respectively: S566_E571delinsK (n = 1), S566_E571delinsR (n = 4), and D842 del (n = 1). The mutations were detected in the classical (n = 5), as well as inflammatory pseudotumor-like (n = 1) Vanek's tumors. The results of this study suggest that the two morphological patterns of Vanek's tumor more probably represent only variants of one type of tumor than two different lesions. Furthermore, BRAF mutations were not shown to drive growth of PDGFRA wild-type Vanek's tumors.

Reactive nodular fibrous pseudotumor: a first report of gastric localization and clinicopathologic review

Reactive nodular fibrous pseudotumor (RNFP) of the gastrointestinal tract is a distinct benign lesion, which could originate from a reactive proliferation of multipotential subserosal cells. This is the first case to be reported in the stomach. It was fortuitously discovered in a 60-year-old man with history of bulbar ulcer and gastritis. Gross examination revealed three lesions in the gastric wall and an adjacent lesion in the lesser omentum. Histologically, lesions were composed of a proliferation of spindle and stellate cells in a dense collagenic hyalinized background containing a mononuclear cell inflammatory infiltrate with numerous lymphoid aggregates and plasma cells with perivascular disposition. Immunohistochemistry showed staining for cytokeratins (AE1/AE3), vimentin and smooth muscle actin, without staining for the neurofilament and S100 proteins, synaptophysin, calretinin, CD117 (c-kit), CD34, desmin, caldesmon or anaplastic lymphoma kinase (ALK-1). Complete excision was performed, and no evidence of disease was found 4 months later. After analysing clinical, morphological and immunohistochemical features of this entity, the main differential diagnoses will be discussed, including calcifying fibrous pseudotumor, which shares morphological characteristics with RNFP, but which immunohistochemistry and the ultrastructural study suggest that it may be a result of another reactive process.