Presence of human herpesvirus-8 DNA sequences and overexpression of human IL-6 and cyclin D1 in inflammatory myofibroblastic tumor (inflammatory pseudotumor)

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.

Inflammatory Myofibroblastic Tumor of the Hilar Bile Duct: A Case Report and Literature Review

Background

Inflammatory myofibroblastic tumor (IMT) is a very rare tumor and occurs seldom in the biliary tract. IMT can occur in any part of the body and in people of any age; however, it most commonly occurs in children or adolescents. Its etiology and pathogenesis are currently unknown. The clinical manifestations of a hilar inflammatory myofibroblastic tumor are atypical, and the imaging examination is nonspecific. The diagnosis is mainly based on histopathology and immunohistochemistry findings, and surgical resection is the preferred treatment method.

Case Description

Herein, we report a rare case of hilar bile duct IMT and review the related literature. Our patient was a 54-year-old woman presenting with a 1-day history of upper abdominal pain as the main clinical symptom. She was misdiagnosed as having cholangiocarcinoma before the surgery. She underwent surgery and was ultimately diagnosed with IMT based on histopathology and immunohistochemistry findings. On 1-year follow-up, no tumor recurrence or related complications were noted.

Conclusions

We hope this case report helps clinicians gain a deeper understanding of biliary IMT of the hilum.

Infant biliary cirrhosis secondary to a biliary inflammatory myofibroblastic tumor: A case report and review of literature

BACKGROUND

A biliary inflammatory myofibroblastic tumor (IMT) is a rare type of mesenchymoma that, although it has a broad age spectrum, usually occurs in adults. Diagnosis is difficult because biliary IMTs often exhibit nonspecific clinical symptoms and imaging features, resulting in delayed or inappropriate treatment. Although most IMTs are benign, some show malignant properties such as infiltration, recurrence, and metastasis.

CASE SUMMARY

Here, we retrospectively describe a 10-month-old infant who was admitted to our hospital due to stubborn jaundice. The patient responded poorly to routine medical treatment and his clinical manifestations and laboratory tests lacked specificity, so we turned to repeated ultrasound scans and other imaging examinations. As both hepatosplenic ultrasonography and diffusion-weighted magnetic resonance imaging demonstrated a space-occupying lesion, an exploratory laparotomy was performed. The final diagnosis made over two mo after the disease onset was infant biliary cirrhosis caused by a biliary IMT, which partially infiltrated into the liver. This infant is the youngest case of biliary IMTs that has been reported till now. The patient underwent an incomplete resection of the mass and Kasai Portoenterostomy. However, because of cirrhosis, he also received a paternal liver transplant. Since some IMTs show malignant properties, we proceeded with a three-year of follow-up; however, no recurrence or metastasis has been noted.

CONCLUSION

Neoplastic disease such as IMTs should be considered when routine medical treatment of obstructive jaundice is not successful. Observation of dynamic imaging changes is helpful for diagnosis. Periodic follow-up is necessary for IMTs.

Features of ophthalmic, magnetic resonance imaging, and histopathology of a feline case of idiopathic sclerosing orbital pseudotumor

In the present report, we describe a case of sclerosing orbital pseudotumor in an 11‐year‐old castrated male American Shorthair cat. Ophthalmic exam showed lagophthalmos, retracted right upper eyelid, and resistant to retropulsion in his right eye. Under magnetic resonance imaging (MRI) scans, increased volume of the extraocular muscles (EOMs) of the right eye was prominent. Immunosuppressive dosage of prednisolone partially ameliorated the clinical signs, but some clinical signs were still gradually progressive or persistent. In the second MRI scan, decreased diameter of the thickened right extraocular muscles was found. After the third MRI scan, enucleation of the right eye was performed due to substantial adverse effects of systemic steroid therapy. Histopathological examination revealed no evidence of neoplastic transformation nor infection. Feline restrictive orbital myofibroblastic sarcoma (FROMS) was therefore excluded, suggesting unknown causes of extensive fibrotic changes in the right orbit of the affected cat.

Case Report: Recurrence of Testicular Myofibroblastic Tumor After Surgery

Inflammatory myofibroblastic tumour (IMT), also known as plasma cell granuloma (PCG) or inflammatory pseudotumour (IPT), is a distinctive, rarely metastasizing neoplasm composed of myofibroblastic and fibroblastic spindle cells accompanied by inflammatory infiltration of plasma cells, lymphocytes and/or eosinophils. IMT predominantly affects children and young adults, and the age at presentation ranges from 3 to 89 years. We present a very rare case of recurrent testicular IMT without ALK rearrangement. This case highlights the clinical characteristics and diagnostic factors associated with primary and recurrent foci of this rare tumour, along with key therapeutic approaches.

Inflammatory myofibroblastic tumor in the pancreatic neck: a rare case report and literature review

Inflammatory myofibroblastic tumor (IMT) is a rare disease of unknown etiology. It usually occurs in abdominal soft tissues and lung, and is extremely rare in the pancreas. IMT can occur in any part of a person at any age, however, it mostly affects children and young people. Its clinical manifestations are atypical, imaging examinations are not specific, and the differential diagnosis of pancreatic malignancies is difficult, making it easily misdiagnosed. Surgical resection is the preferred method of treatment for IMT. In this case report, we report a rare case of IMT in the neck of the pancreas and reviewed the relevant literature. In our case, the patient was a 57-year-old woman with an IMT in the neck of the pancreas. Abdominal pain was the only clinical symptom, and imaging features were not specific. She underwent surgery to remove the pancreatic mass, and the final diagnosis of IMT was based on histopathology and immunohistochemistry. After 6 months of regular follow-up, the patient had no complications or further incidents. The purpose is to emphasize the difficulty of the preoperative diagnosis of pancreatic IMT and the difficulty of distinguishing it from pancreatic malignancies. It is hoped that clinicians can gain a deeper understanding of pancreatic IMT through this case report.

Colonic inflammatory myofibroblastic tumour presenting as 'pyrexia of unknown origin': report of a rare disease and its unique presentation

An intra-abdominal inflammatory myofibroblastic tumour (IMT) belongs to a rare group of diseases initially described as an inflammatory pseudotumour. Even though it is seen more often in children, its incidence in adults is even rarer. Clinical presentations can vary depending on its site and inherent tumour properties. The colon is an uncommon site for IMT and pyrexia of unknown origin (PUO) as its dominant clinical presentation is even rarer. A 27-year-old woman presented with PUO. She was evaluated under the department of internal medicine before undergoing an 18F-fluorodeoxyglucose positron emission tomography-computed tomography scan. This showed an intensely enhancing descending colon mass. An image-guided biopsy of this lesion was reported as IMT. She underwent a left hemicolectomy and complete excision of the tumour, following which her symptoms resolved completely. The patient has been disease-free at a 6-month follow-up and is asymptomatic at 1 year.

Echocardiographic Findings in Children with Native Mitral Valve Masses Complicated by Systemic Embolization

• Case of mitral valve IMT with embolization. • Case of Streptococcus pneumoniae mitral valve endocarditis with embolization. • Use of 2D and 3D echocardiography for management of mitral valve masses.

Acute Intestinal Obstruction Due to Ileocolic Intussusception in an Adult; A Rare Presentation of Inflammatory Myofibroblastic Tumor

Patient: Female, 40-year-old

Final Diagnosis: Inflammatory myofibroblastic tumor

Symptoms: Obstipation • pain • vomiting

Medication: —

Clinical Procedure: Exploratory laparotomy followed by right hemicolectomy

Specialty: Surgery

Emerging Roles of ALK in Immunity and Insights for Immunotherapy

Anaplastic lymphoma kinase (ALK) is mostly known for its oncogenic role in several human cancers. Recent evidences clearly indicate new roles of ALK and its genetic aberrations (e.g. gene rearrangements and mutations) in immune evasion, innate and cell-mediated immunity. New ALK-related immunotherapy approaches are demonstrating both preclinical and clinical promises. Here, we provide a timely review on the most updated laboratory and patient-related findings on ALK and immunity, which would grant us important insights for the development of novel ALK immunotherapies for ALK-altered cancers.

How long should we continue crizotinib in ALK translocation-positive inflammatory myofibroblastic tumors? Long-term complete response with crizotinib and review of the literature

INTRODUCTION

Inflammatory myofibroblastic tumor is a rare disease which is typically seen in children and young adults. Approximately half of the inflammatory myofibroblastic tumors contain translocations that result in over-expression of anaplastic lymphoma kinase gene. Herein, we present two anaplastic lymphoma kinase-positive cases with long-term remission with crizotinib. We do not know how long these therapies need to be continued.

CASE REPORTS

We present two cases of inflammatory myofibroblastic tumor treated with anaplastic lymphoma kinase inhibitor therapies: an 8-year-old Turkish boy and a 21-year-old Caucasian man.

MANAGEMENT AND OUTCOME

Two cases, both with good tumor control under crizotinib, but one who progressed on drug holiday, responded again to the same drug, and had a very short period of response after restarting crizotinib.

CONCLUSION

A molecular-targeted drug (anaplastic lymphoma kinase inhibitor) was found to be extremely effective as selective therapy for inflammatory myofibroblastic tumor with anaplastic lymphoma kinase translocation. Here, we want to emphasize the continuation of this treatment after achieving a good response until progression or a major side effect.

Anaplastic Kaposi's Sarcoma of the Adrenal in an HIV-negative Patient With Literature Review

Kaposi's sarcoma (KS) is a peculiar tumor of viral etiology, with the HHV8 rhadinovirus playing a fundamental role in its development. Several epidemiological categories of KS have been identified, of which the sporadic, endemic, iatrogenic, and the epidemic are the main ones. Several histologic disease morphologies have been described, such as inflammatory, angiomatous, spindle cell, mixed, and the anaplastic (sarcomatous) subtypes. The skin of the limbs is most commonly affected, but any other organ or site may be involved. Microscopically KS may enter the differential diagnosis with several different entities, and for this purpose the immunohistochemical detection of the viral latent nuclear antigen-1 (LNA-1) may be crucial. Sporadic KS is usually benign, but rarely it may be aggressive. Anaplastic histology heralds an ominous course in any clinical context. We report a case of anaplastic retroperitoneal KS, occurring in an HIV-negative adult man. This patient presented with a huge left suprarenal mass, which was totally resected, and initially diagnosed as inflammatory leiomyosarcoma, because of the monomorphic spindle cell tumor morphology. After 12 years the tumor recurred locally as an unresectable mass, which was biopsied and examined. At the time of recurrence, the histologic slides of the primary tumor were reviewed, and the previous diagnosis was changed to that of atypical KS. Histologically the recurrent tumor showed both spindle cell and epithelioid appearances. Strongly diffuse HHV8/LAN-1 immunopositivity was documented in both tumors. The final diagnosis for the entire case was anaplastic KS. Then, the patient died in a few months.

Detection of bovine papillomavirus type 2 DNA in calf conjunctival myofibroblastoma

An 8-month-old male Japanese Black calf was referred for the evaluation of a slow-growing conjunctival mass in the right eye. A superficial keratectomy was performed followed by recurrence on two occasions. No metastases were found in surrounding tissues. Histological, immunohistochemical, and ultrastructural investigation revealed that both the primary and the recurrent lesions were benign, conjunctival, myofibroblastomas. Interestingly, bovine papillomavirus type 2 (BPV-2) DNA was detected in both myofibroblastoma lesions. Archival bovine myofibroblastomas from the vulva and neck were also analyzed for papillomaviral genomes. BPV-2 DNA was also amplified from these lesions. To the best of our knowledge, this is the first report describing a potential causal relationship between BPV-2 infection and conjunctival myofibroblastoma.

An interesting case of inflammatory myofibroblastic tumor presenting as cholangiocarcinoma

INTRODUCTION

Inflammatory myofibroblastic tumor (IMT) is a reactive or inflammatory state mostly affecting the pulmonary system and commonly occurs in children and young adults. IMT presentation in the hepatic duct bifurcation is very rare and has sporadically been reported before.

PRESENTATION OF CASE

A 12-year-old girl presented with jaundice, pruritus which had begun 5 weeks previously. Ultrasound revealed intrahepatic biliary ductal dilation and an isoechoic 25*30mm lesion at or near the confluence of the right and left hepatic ducts that were suggestive of a hilar cholangiocarcinoma. Limited resection was decided intraoperatively because the intraoperative frozen section assessment of the CBD, right and left hepatic duct wall samples and porta hepatis lymph nodes was normal. Histologically the tumor proved an inflammatory myofibroblastic tumor (IMT).

DISCUSSION

Almost all patients with resectable IMT should be managed with radical surgical resection or single nonsteroidal anti-inflammatory drugs. In addition, conservative treatments with NSAIDs, corticosteroids or chemotherapeutic agents could not be started in many cases due to the lack of definitive diagnosis of the mass preoperatively. Thus, surgical removal is frequently unavoidable.

CONCLUSION

Biliary IBT is extremely rare and should be considered by all hepatobiliary surgeons dealing with the teens with cholangiocarcinoma, to avoid unnecessary major surgical resections.

Inflammatory myofibroblastic tumor of the pancreatic head - a case report of a 6 months old child and review of the literature

BACKGROUND

Inflammatory myofibroblastic tumors are rare in the pediatric population. Most common localizations were reported in the lungs. A localization in the pancreas needs differentiation from other tumors and chronic pancreatitis. Treatment is surgical resection, although there are reports of treatment with oral steroids and radiation therapy.

CASE REPORT

A 6-month-old child was treated due to a tumor in the head of the pancreas. On admission he was jaundiced with pruritus. US and MRI confirmed pancreatic tumor. Preoperative biopsy wasn't conclusive regarding the nature of the tumor. Duodenopancreatectomy was performed. Postoperative course was uneventful. Histologic examination confirmed the diagnosis of inflammatory myofibroblastic tumor. On follow up, he remained with no evidence of recurrence.

CONCLUSIONS

A literature review revealed 10 cases of pancreatic inflammatory myofibroblastic tumors in the pediatric age group. Our patient is the youngest reported. Despite major resection, there were no complications. However, management of this child might be possible with steroids, but conservative treatment might be insufficient, especially in aggressive forms of tumors.

Intranodal palisaded myofibroblastoma: another mesenchymal neoplasm with CTNNB1 (β-catenin gene) mutations: clinicopathologic, immunohistochemical, and molecular genetic study of 18 cases

Intranodal palisaded myofibroblastoma is a benign, lymph node-based myofibroblastic tumor of unknown pathogenesis. We report the clinicopathologic, immunohistochemical, and molecular genetic features of this rare entity. The study cohort consisted of 14 men and 4 women ranging in age from 31 to 65 (mean, 47; median 49) years with tumors arising in inguinal lymph nodes (n=15), a neck lymph node (n=1), and undesignated lymph nodes (n=2). Most individuals presented with a painless mass or lump. Possible trauma/injury to the inguinal region was documented in 4 cases. Tumors ranged in size from 1.0 to 4.2 (mean, 3.1; median; 3.0) cm. Microscopically, the process presented as a well-circumscribed, oftentimes pseudoencapsulated nodule (n=17) or nodules (n=1). Tumors consisted of a cellular proliferation of cytologically bland, spindled cells arranged in short fascicles and whorls within a finely collagenous (n=11) or myxocollagenous (n=7) matrix. In 12 tumors, scattered fibromatosis-like fascicles of spindled cells were noted. Histologic features characteristic of the process included nuclear palisades (n=16 cases), collagenous bodies (n=15), and perinuclear intracytoplasmic hyaline globules (n=10). Mitotic activity ranged from 0 to 8 (mean, 2; median, 1) mitotic figures/50 high-powered fields with no atypical division figures identified. Immunohistochemically, all tumors tested expressed smooth muscle actin and/or muscle-specific actin (n=5, each), and nuclear β-catenin and cyclin D1 (n=8, each). The latter 2 results prompted a screening for mutations in the β-catenin gene glycogen synthase kinase-3 β phosphorylation mutational "hotspot" region in exon 3 using polymerase chain reaction amplification and Sanger sequencing. Single nucleotide substitutions leading to missense mutations at the protein level were identified in 7 of 8 (88%) analyzed tumors and are responsible for the abnormal expression of β-catenin and cyclin D1. These results demonstrate that mutational activation of the β-catenin gene is likely a pivotal event in the pathogenesis of intranodal palisaded myofibroblastoma.

Maxillary sinus inflammatory myofibroblastic tumors: a review and case report

An inflammatory myofibroblastic tumor (IMT) is an immunohistochemically diverse entity demonstrating neoplastic and nonneoplastic qualities. Although IMTs can arise in any area of the body, lesions arising in certain sites, namely, the nasal cavity, paranasal sinuses, and pterygopalatine fossa, demonstrate a heightened neoplastic and invasive potential. Despite case specific complete tumor regression and disease remission in response to pharmacotherapeutics, a subset of IMTs remain resistant to all forms of therapy. We present such a case, a 34-year-old female patient, with a highly resistant, maxillary sinus IMT. Her refractory, ALK-1 negative IMT has not responded well to novel therapies reported in current literature. This case suggests the role of zonal expressivity within a single lesion as a probable mechanism for its highly resistant nature and should promote determination of each IMT's cytogenetic profile to provide more effective targeted therapy. Paper includes a literature review of all maxillary sinus IMTs from 1985 to 2014 along with their immunohistochemical staining, treatments, and outcomes.

Inflammatory myofibroblastic tumor of the upper alveolus: A rare entity presenting as a jaw swelling

Inflammatory myofibroblastic tumor (IMT) is a rare tumor of borderline nature that can clinically present as a malignant neoplasm. It commonly occurs in the lungs, and a very few oral IMTs have been reported in the literature. IMT consists of inflammatory cells and myofibroblastic spindle cells. The diagnosis of IMT requires histopathological examination with immunohistochemical staining to look for the expression of smooth-muscle actin for confirmation of the diagnosis. The objective of this paper is to report an IMT on the upper alveolus with clinic-a pathological similarity with a malignant lesion and its management. Though oral IMTs are rare, it should be considered in the differential diagnosis of tumors of the upper jaw. Complete surgical excision of alveolar IMT is the treatment of choice because of its unpredictable clinical behavior. The patients with oral IMTs require periodic post-surgical follow-up for recurrence.

Inflammatory pseudotumor of the colon causing intussusception: A case report and literature review

Inflammatory pseudotumor (IPT) is a rare space-occupying lesion of unknown etiology that can mimic malignancy on clinic-radiological and pathological examination. We describe a rare case of ileocecal intussusception from clinically suspected malignancy of the right colon where the patient underwent right hemicolectomy. Histopathology of the resected specimen confirmed IPT of the colon. This patient was observed to have abnormally elevated total leukocyte count and platelets before and after surgery. In an adult with intussusception associated with an abdominal mass, the possibility of IPT of the colon should be considered. Considering the abnormally high total leukocyte and platelet counts and colonic IPT, it is necessary to prevent postoperative adverse effects due to these changes. Although IPT of the colon is usually a benign process, controversy regarding its management still exists. We consider hemicolectomy as a safe treatment approach for colonic IPT and review the existing literature.

A large inflammatory myofibroblastic tumor involving both stomach and spleen: A case report and review of the literature

Inflammatory myofibroblastic tumor (IMT) is a rare, benign neoplasm that most commonly occurs in pediatric patients; it has been described as a pseudosarcomatous proliferation of spindled myofibroblasts mixed with lymphoplasmacytic cells. IMT has been reported in a number of locations throughout the body; however, cases occurring in the gastrointestinal tract are rare and to date, no case involving both the stomach and spleen has been reported. The current study presents a case of an extremely large IMT invading both the stomach and spleen in a 50-year-old female, presenting with a three-month history of left-sided abdominal distension without abdominal pain, fever or vomiting. As the tumor had invaded the stomach and spleen, it was completely excised and concomitantly, the entire stomach and spleen were removed. Histological examination of the biopsy revealed fascicles of spindle cells in a mixed inflammatory background, with inflammatory cells that were immunopositive for vimentin, smooth muscle actin, and negative for anaplastic lymphoma kinase and CD30, confirming the diagnosis of IMT. Four months following local excision of the mass, accompanied by a total gastrectomy and splenectomy, no abdominal distension, abdominal pain, fever or vomiting were observed and no IMT recurrence was identified.

Low-grade myofibroblastic proliferations of the urinary bladder

CONTEXT

Myofibroblastic proliferations of the urinary bladder, which share some similarities with nodular fasciitis, were first reported in 1980. Since then, they have had several designations, the most frequently used being inflammatory myofibroblastic tumor. Based on both histopathologic and prognostic grounds, some authors prefer the term pseudosarcomatous myofibroblastic proliferation, at least for some of the proliferations. These same scientists also assimilate the so-called postoperative spindle cell nodules with the pseudosarcomatous myofibroblastic proliferations. Little is known about these low-grade myofibroblastic proliferations.

OBJECTIVES

To review the literature about low-grade myofibroblastic proliferations occurring in the urinary bladder.

DATA SOURCES

Textbooks and literature review. We obtained most of the clinicopathologic peculiarities from a patient population composed of the most-relevant, previously reported cases.

CONCLUSIONS

The low-grade myofibroblastic proliferations of the urinary bladder are rare lesions affecting males more often than they do females. The most-common signs and symptoms are hematuria and dysuria. Histopathologically, they are spindle cell proliferations in a loose myxoid stroma, even though compact proliferations or hypocellular fibrous patterns can be found. Immunohistochemistry is quite nonspecific, except for ALK-1 positivity (20%-89%). Fluorescence in situ hybridization has demonstrated clonal genetic aberrations involving the ALK gene in 50% to 60% of cases. After surgery, only 6% of patients experience local recurrence, without metastases or deaths from the disease. Malignant transformation has been reported exceptionally. These myofibroblastic proliferations are probably part of a continuum with, at one end, benign pseudosarcomatous proliferations and, at the opposite end, more-aggressive lesions. Because of the frequently indolent clinical course, aggressive treatment would be unjustified.

Diagnostic and therapeutic challenges of a large pleural inflammatory myofibroblastic tumor

We report a 48-year-old woman with a pleural pseudoneoplasm requiring different diagnostic and therapeutic strategies. After initial presentation with increasing dyspnoea, temperature, dry cough, and interscapular pain diagnostic processing showed a large mediastinal mass with marked pleural effusion and high metabolic activity in the 18F-FDG-PET/CT. Extensive CT-guided biopsy of the tumor reaching from the visceral pleura into the right upper lobe revealed no malignancy, but a marked inflammatory tissue reaction containing foam cells. Initial empiric antibiotic therapy was temporarily successful. However, in the further course the mass relapsed and was resistant to antibiotics and a corticosteroid trial. With the working hypothesis of an inflammatory myofibroblastic tumor the patient underwent surgical tumor resection, finally confirming the suspected diagnosis. Due to residual disease intravenous immunoglobulins were administered leading to sustained response. This case with a pleural localisation of a large inflammatory pseudotumor with responsiveness to immunomodulation after incomplete resection extends the reported spectrum of thoracopulmonary manifestations of this rare entity.

Vaginal superficial myofibroblastoma: a rare mesenchymal tumor of the lower female genital tract and a study of its association with viral infection

Superficial myofibroblastoma is a rare mesenchymal tumor in the lower female genital tract. The exact etiology of superficial myofibroblastoma remains unclear. The association of viral infection and mesenchymal tumors has been well established in some particular types of soft tissue tumors. In the lower female genital tract, the intimate correlation of viral infection and tumor pathogenesis has been also proposed. We present a 59-year-old woman with postcoital bleeding for 1 month. The pelvic examination revealed a 2-cm polypoid mass mimicking leiomyoma at the vaginal fornix. Local excision was performed, and the pathological examination revealed a superficial myofibroblastoma. No tumor recurrence was noted during the 12-month follow-up. Pathological differential diagnosis of this tumor from other mesenchymal tumors is essential because of its distinct clinicopathological features. Furthermore, fluorescence in situ hybridization of human papilloma virus (HPV) and Epstein-Barr virus (EBV), as well as immunohistochemical staining of human herpesvirus 8 (HHV8), was negative in tumor cells. To the best of our knowledge, we are the first group to study the possible relationship of viral infection and the occurrence of this mesenchymal tumor. Our results suggested no association of vaginal superficial myofibroblastoma and infection with HPV, EBV, or HHV8.

Fibroblastic and myofibroblastic tumors in children and adolescents

Fibroblastic and myofibroblastic tumors in children and adolescents are a relatively common group of soft tissue proliferations that range from reactive to hamartomatous to neoplastic, with a full spectrum of benign, intermediate, and malignant neoplasms. These lesions are diagnostically challenging because of morphologic and immunohistochemical overlap, despite significant clinical, genetic, and prognostic differences. The fibromatoses are a major subgroup, and all types of fibromatoses can occur in the 1st 2 decades of life. Intermediate and malignant fibroblastic-myofibroblastic tumors are an important group that includes variants of fibrosarcoma and other tumors with recurrent cytogenetic or molecular genetic abnormalities and low metastatic potential. Pathologic examination is enhanced by adjunct techniques, such as immunohistochemistry, cytogenetics, and molecular genetics, although morphology provides the ultimate criteria for a specific diagnosis. This article reviews the clinicopathologic features of fibroblastic and myofibroblastic tumors with an emphasis on the unique aspects of these neoplasms in children and adolescents, the use of diagnostic adjuncts, and differential diagnoses.

Differential diagnosis of inflammatory myofibroblastic tumour and low-grade myofibroblastic sarcoma: two case reports with a literature review

Inflammatory myofibroblastic tumour (IMT) and low-grade myofibroblastic sarcoma (LGMS) have similar morpho logical and immunophenotypic features, but LGMS is more malignant than IMT and the treatment requires a wider surgical margin plus post-operative chemotherapy or radiotherapy. To date, only 28 cases of IMT and two cases of LGMS have been reported in the laryngopharynx. Recent studies have suggested that anaplastic lymphoma kinase (ALK) and cytokeratin are important markers for differentiating between the two tumours. Here, two cases involving different myofibroblastic tumours of the larynx are reported. Based on the histological and immunohistochemical results, case 1 was diagnosed as IMT involving the right arytenoepiglottic fold, while case 2 was diagnosed as LGMS involving the epiglottic-glossal surface. There was no recurrence or metastasis in either case after post-operative follow-up (12 and 14 months, respectively). It is difficult to distinguish IMT from LGMS; both morphological and immunohistological analyses are required.

Unresectable multifocal omental and peritoneal inflammatory myofibroblastic tumor in a child: revisiting the role of adjuvant therapy

Inflammatory myofibroblastic tumor is an uncommon lesion, also called pseudotumor, with a variable natural course from benign with spontaneous regression to mimicking malignant tumors. We report a case of diffuse peritoneal and omental pseudotumor in a 10-year-old boy characterized by aggressive behavior at the onset followed by stability after subtotal resection and chemotherapy. Total excision was not possible because of the tumor dissemination over the whole peritoneal surface. Adjuvant antiinflammatory drug (ketorolac tromethamine) and chemotherapy (methotrexate-vinblastine followed by ifosfamide-adriamycin and ifosfamide alone) were helpful to obtain rapidly complete resolution of clinical symptoms and anatomic stability of the residual lesions. Long-term evolution, in the absence of continued therapy, has been characterized by progressive involution and reduction of the residual masses.

Inflammatory Myofibroblastic Tumor of the Pancreatic Head: An Unusual Cause of Recurrent Acute Pancreatitis - Case Presentation of a Palliative Approach after Failed Resection and Review of the Literature

Inflammatory myofibroblastic tumors (IMTs) are a rare cause of echo-poor pancreatic head enlargement. Histologically, IMTs are characterized by spindle-shaped myofibroblasts or fibroblasts accompanied by a mixed immune cell infiltration. The most common localizations of IMTs have been reported in lung, mesentery and omentum, especially in children and young adults. IMTs show infiltrating growth, multilocular appearance and also metastasis have been reported. Curative resection is the only therapeutic option so far. In the palliative situation, evident data and clear guidelines for this rare tumor entity are missing. We report on a 44-year-old male with an unresectable IMT of the pancreatic head causing recurrent episodes of acute pancreatitis that resulted in a chronic obstructive course of the disease. The patient entered a palliative therapeutic regimen including radiation therapy and antiinflammatory medication. In a regular follow-up of 12 months, he presented with stable disease after initial progression. This case of local progressive IMT of the pancreatic head was managed with a palliative therapeutic regimen and is discussed based on the current literature.

Radiological appearance of inflammatory myofibroblastic tumour

Inflammatory myofibroblastic tumour (IMFT) is a distinct entity with variable clinical presentation and therapeutic options. We present three paediatric cases of IMFT, originated from the lung, bladder and ovary respectively. All lesions were heterogeneous, with mixed solid/cystic components and infiltrative pattern, and were interpreted as aggressive malignant neoplasms initially due to their bizarre imaging appearance. The definitive diagnosis was derived from characteristic histopathological features.

Inflammatory myofibroblastic tumors in childhood: a report from the Italian Cooperative Group studies

BACKGROUND

Inflammatory myofibroblastic tumors (IMTs) are myofibroblastic lesions with unpredictable biologic behavior that occur at a young age. For this report, the authors investigated clinicopathologic features in a series of pediatric IMTs. The objective of the study was to identify morphologic or immunohistochemical prognostic markers and the possible pathogenic role of human herpes virus 8 (HHV-8).

METHODS

Twenty-six patients were observed over a period of 18 years. Clinical/histologic data were reviewed, and immunohistochemical/molecular studies were performed.

RESULTS

Patients ages 8-216 months (median age, 60 months) presented with tumors of the lung-bronchus (8 patients), abdomen (17 patients), and thoracic wall (1 patient). Twenty-one patients underwent complete excision, and microscopic or macroscopic residual disease was present in 5 of those patients. Chemotherapy was received by 5 patients. After a median follow-up of 6.6 years, 24 patients were in complete remission, and 2 patients had died of disease. Local recurrences were observed in 6 patients (including 4 recurrences that occurred after a complete excision). Cytologic atypia, low inflammatory infiltrate, and a rich myxoid pattern were detected in patients who had recurrent disease or a poor prognosis. Anaplastic lymphoma kinase (ALK) was positive in 7 patients (including 2 patients with recurrent disease). No correlation between clusterin expression and prognosis was demonstrated. HHV-8 was identified in 1 pulmonary IMT.

CONCLUSIONS

IMTs are locally aggressive lesions. In this series, the local recurrence rate was 23%, and the 5-year and 10-year event-free survival rates were 87.4% and 72.8%, respectively. The results indicated that the treatment of choice is a complete, nonmutilating excision; chemotherapy may be given to patients who have microscopic or macroscopic residual disease, although the results are controversial; cytologic atypia and positive ALK status are more frequent in aggressive tumors, whereas metastatic tumors are negative for ALK; and HHV8 is not involved in the pathogenesis of IMT.

Inflammatory myofibroblastic tumor involving lung and brain in a 10-year-old boy: a case report

Inflammatory myofibroblastic tumors are rare tumors of unknown etiology, composed of proliferating myofibroblasts and accompanying lymphoplasmacytic infiltration. A 10-year-old boy who developed inflammatory myofibroblastic tumors in the lung as well as the brain is described. Surgery and radiation therapy were not feasible. The authors review the current literature and treatment options.

Anaplasic lymphoma kinase positive inflammatory myofibroblastic tumour with renal pelvic calculus: a case report

Inflammatory myofibroblastic tumour is a distinctive mesenchymal neoplasm, composed of a variable admixture of myofibroblastic spindle-shaped and inflammatory cells which were originally described in the lung, as a nonneoplastic lesion and designated as an inflammatory pseudotumour. The lack of certainty of the IMTs pathogenesis is reflected in the large number of terms which have been attributed to this lesion. Recent genetic and molecular studies of IMTs have showed chromosomal abnormalities of 2p23 resulting in a rearrangement of the anaplasic lymphoma kinase gene and have also provided evidence for a monoclonal, noeplastic origin for IMT.Occurrence of IMT in the kidney is very rare, and to our knowledge, only 30 such cases have been described in the literature.This report describes an original case of an ALK positive IMT of the kidney associated with renal pelvic calculus which we believe has never been reported. The differential diagnosis of IMTs will also be discussed.

Posterior fossa intracranial inflammatory pseudotumor: a case report and literature review

BACKGROUND

Intracranial inflammatory pseudotumors are rare. This study describes an intracranial inflammatory pseudotumor at the left cerebellopontine angle. It is the second documented posterior fossa intracranial inflammatory pseudotumor, and it was treated by surgery and radiotherapy.

CASE DESCRIPTION

A 49-year-old man presented with dizziness for 3 months and mild hoarseness for 1 month. Brain CT detected an intracranial tumor at the left cerebellopontine angle. Magnetic resonance imaging revealed a 3.6-cm heterogeneously enhancing mass. Suboccipital craniectomy with ventriculostomy was performed. The mass was well defined with a smooth surface, enclosed the low cranial nerves, and adhered to the dura matter. Pathologic examination revealed fibrous collagenous stroma with dense infiltrates of small lymphocytes and uninucleated histiocytes. Immunopositivity for T-200 and CD-68 was noted. Special staining for mycobacteria and fungus was negative. Serologic tests were positive for EBEA-Ab, EBNA-Ab, and EB-VCA-IgG. An inflammatory pseudotumor was diagnosed. Local recurrence was found 6 months later with a left oculomotor nerve palsy. Whole-brain irradiation with a total dose of 1200 cGy in 6 fractionations was done. Remission was found in follow-up neuroimages, and no recurrence was noted in 2 years' follow-up.

CONCLUSION

Based on serologic findings and a literature review, the pathogenetic mechanism of this rare intracranial tumor is believed to be chronic reactive EBV infection. We propose that radiotherapy may be the best treatment option in the case of local recurrent intracranial inflammatory pseudotumors.

Inflammatory myofibroblastic tumors of the genitourinary tract--single entity or continuum?

PURPOSE

Inflammatory myofibroblastic tumor of the genitourinary tract is a spindled soft tissue lesion that is often mistaken for sarcoma. These tumors have been described in numerous sites in the body and have been assigned many names. The relationship between inflammatory myofibroblastic tumor and other morphologically similar entities has been a long-standing source of controversy. We investigated whether inflammatory myofibroblastic tumors in adults and children are the same entity, and whether inflammatory myofibroblastic tumor is part of a biological spectrum that includes benign and malignant entities at opposite ends.

MATERIALS AND METHODS

We performed an extensive review of the literature.

RESULTS

The literature suggests that with evidence of anaplastic lymphoma kinase rearrangement and expression, the lesion is neoplastic rather than reactive, differentiating it from previously described lesions.

CONCLUSIONS

Inflammatory myofibroblastic tumor of the genitourinary tract should be considered a neoplasm of uncertain malignant potential, and routine surveillance and close clinical followup are recommended. Aggressive therapy (radical cystectomy, radiation or chemotherapy) is unwarranted given the indolent and often benign clinical course for the majority of cases. To understand the diagnostic and prognostic implications future emphasis should be placed on the link between genetic abnormalities, and clinical course, therapeutic response and ultimate outcome.

Inflammatory myofibroblastic tumor of the central nervous system and its relationship to inflammatory pseudotumor

Inflammatory myofibroblastic tumor (IMT) is a distinctive spindle cell lesion and occurs primarily in soft tissue. Recent evidence suggests a neoplastic nature, although historically, both neoplastic and nonneoplastic processes were combined in this category. Originally described as a nonneoplastic process, the term inflammatory pseudotumor (IP) has been used synonymously with IMT. IMTs have been linked to ALK gene (2p23) rearrangements, and some have suggested an association with the human herpesvirus 8 (HHV-8). IMT in the central nervous system (CNS) is rare, its characteristics are poorly defined, and its relation to similar tumors at other sites is unclear. To better characterize IMT within the CNS, we studied clinicopathologic features of 6 IMTs and compared them with 18 nonneoplastic lesions originally classified as IP. The IMT group consisted of 2 male and 4 female patients with a median age of 29 years. Of the six IMTs, 5 occurred within the cerebral hemispheres, and one was in the posterior fossa. All tumors were composed of neoplastic spindle cells and a variable amount of inflammatory infiltrate. Eighteen IPs included in this study consisted of predominantly inflammatory masses occasionally seen in the setting of systemic diseases. Only 1 IMT and none of the IPs recurred during the follow-up period. Four IMTs had either ALK protein overexpression or 2p23 rearrangement, and 1 case demonstrated both. None of the IPs were positive for ALK. Neither IMT nor IP cases demonstrated HHV-8 expression. We suggest that IMT in the CNS is distinct from the nonneoplastic IP, and distinguishing IMT from nonneoplastic lesions should enable better decisions for patient management.

Splenic inflammatory pseudotumor (inflammatory myofibroblastic tumor)

We report a case of a splenic inflammatory pseudotumor (myofibroblastic tumor) in a 43-year-old man with a 5-year history of chronic bronchitis and sleep apnea syndrome. The patient was hospitalized because of a screen-detected splenic mass lesion. His sputum cultures revealed Mycobacterium avium complexes on only one occasion. Imaging studies revealed a 7 cm solitary tumorous lesion, and differential diagnoses of splenic hamartoma, hemangioma, lymphoma, and angiosarcoma were obtained from the radiologist. A splenectomy followed by pathological investigations was performed. By histology, the lesion contained fibroblastic or myofibroblastic spindle cell proliferations, accompanied by variable degrees of inflammatory cell infiltration. Ziehl-Neelsen staining did not reveal acid-fast bacteria. Immunohistochemically, the fibroblastic or myofibroblastic spindle cells were positive for vimentin, human smooth muscle actin, and muscle actin, but negative for desmin, CD8, CD21, CD23, CD35, p80, Epstein-Barr virus LMP, and human herpesvirus type 8. The infiltrating lymphoid cells demonstrated a nonneoplastic pattern. The results of in situ hybridization for Epstein-Barr virus encoded RNA were negative. The postoperative course was uneventful and he has had no recurrence in 22 months. His sleep apnea syndrome and chronic bronchitis have resolved spontaneously since the splenectomy.

Pediatric pulmonary tumors: primary and metastatic

Pediatric pulmonary tumors are rare. There is often a significant delay in diagnosis of pulmonary tumors secondary to their rarity and nonspecific presenting physiologic and radiographic findings. A high index of suspicion in pediatric patients with recurrent or persistent pulmonary symptoms is of paramount importance in diagnosing pulmonary tumors at an early stage. Malignant pulmonary tumors are more frequently diagnosed than benign lesions, with metastatic cancers being the most common. Complete surgical resection remains the basis of therapy for primary lesions, and its role in secondary cancers is becoming more established. Adjuvant therapies are frequently employed depending on the precise tumor involved. Mortality rates vary greatly depending on tumor location, stage, and type.

Bilateral infiltrating renal inflammatory pseudotumor responsive to corticosteroid therapy

Inflammatory pseudotumor (IPT) is a quasi-neoplastic lesion that most commonly involves the lung, but has been shown to occur in nearly every tissue type. Renal involvement is very uncommon. We report the second case of IPT ever published presenting as bilateral infiltrating renal masses. Although most renal IPTs were treated with nephrectomy, our patient was managed successfully with conservative steroid treatment, thereby avoiding the alternative of dialysis or kidney transplantation.

Inflammatory myofibroblastic tumours: where are we now?

Inflammatory pseudotumour is a generic term applied to a variety of neoplastic and non-neoplastic entities that share a common histological appearance, namely a cytologically bland spindle cell proliferation with a prominent, usually chronic inflammatory infiltrate. Over the last two decades, inflammatory myofibroblastic tumour (IMT) has emerged from within the broad category of inflammatory pseudotumour, with distinctive clinical, pathological and molecular features. IMT shows a predilection for the visceral soft tissues of children and adolescents and has a tendency for local recurrence, but only a small risk of distant metastasis. Characteristic histological patterns include the fasciitis-like, compact spindle cell and hypocellular fibrous patterns, which are often seen in combination within the same tumour. Chromosomal translocations leading to activation of the ALK tyrosine kinase can be detected in approximately 50% of IMTs, particularly those arising in young patients. This review will examine the clinical, pathological, and molecular genetic features of IMT and discuss an approach to diagnosis and differential diagnosis.

Absence of human herpesvirus-8 in pulmonary inflammatory myofibroblastic tumor: immunohistochemical and molecular analysis of 20 cases

Inflammatory myofibroblastic tumors are uncommon lesions composed of spindled myofibroblasts within a variable background of collagen and inflammatory cells. Although the true nature of these lesions is not fully elucidated, identification of consistent cytogenetic alterations in the anaplastic lymphoma kinase (ALK) gene suggests that they may be neoplastic. A small number of inflammatory myofibroblastic tumors have been reported to harbor human herpesvirus-8 (HHV-8), implicating the virus in its pathogenesis. In this study, 20 cases of pulmonary inflammatory myofibroblastic tumor were analyzed for the presence of HHV-8 with immunohistochemical and molecular methods. In all cases, antibodies to the latent nuclear antigen of the virus were applied. Four open reading frames (ORFs), including ORFs K2, 16, 26, and 72, were targeted utilizing real-time polymerase chain reaction (PCR). The cohort included 9 men and 11 women with a mean age of 37 years (range, 1-81). Microscopically, the tumors were composed of cytologically bland spindle cells with myofibroblastic differentiation. On immunohistochemical studies, 20% of cases (4/20) demonstrated diffuse cytoplasmic positivity with ALK. Immunohistochemical staining for the latent nuclear protein of the virus was negative in all cases (0/20). All tumors (100%, 20/20) tested with real-time PCR were negative for all four ORFs, whereas 100% (10/10) of positive control Kaposi sarcoma cases were positive. Her2 gene expression was present in all (20/20) inflammatory myofibroblastic tumors confirming the presence of amplifiable deoxyribonucleic acid in the tissue lysate. This study documents the absence of HHV-8 in pulmonary inflammatory myofibroblastic tumors, suggesting that further investigation is required to clarify the pathogenesis of this lesion.

Extraorbital Skull Base Idiopathic Pseudotumor

OBJECTIVES/HYPOTHESIS

The term idiopathic pseudotumor (IP) refers to a nonspecific, nonneoplastic inflammatory process without identifiable local or systemic causes, which is one of the most common causes of intraorbital space-occupying lesions. Occasionally, orbital pseudotumors may extend to other areas of the skull base. Rarely, pseudotumors may present as a skull base mass with no involvement of the orbit. The ophthalmology literature has detailed reviews of IP as an intraorbital space-occupying lesion, but lesions involving only the skull base and sparing the orbit are rare in the literature. We present a review of our experience with six patients with extraorbital skull base pseudotumor and a review of the relevant literature.

METHOD

Retrospective case study.

RESULTS

We treated six patients with extraorbital skull base pseudotumor between 1996 and 2004. Four patients had lesions in the pterygopalatine and/or infratemporal fossae, and two patients had lesions in the superior aspect of the parapharyngeal space. Five patients had excellent initial response to steroids. Two of the pseudotumors recurred. One patient partially responded to steroids and is currently stable with limited disease. Our literature review demonstrated 16 previously published reports of IP of the skull base sparing the orbit.

CONCLUSIONS

A well-documented intraorbital lesion, inflammatory pseudotumor may present outside the orbit. Treatment of IP of the skull base is controversial and may involve corticosteroids or surgical resection, or both. Other chemotherapeutic agents and radiotherapy may be considered in steroid-resistant patients. Pathological subtype, ease and safety of resection, safety of high-dose corticosteroid use, the surgeon's comfort, and the patient's preference must be included in the decision-making process for treatment.