Inflammatory myofibroblastic tumor: comparison of clinicopathologic, histologic, and immunohistochemical features including ALK expression in atypical and aggressive cases

Extrauterine inflammatory myofibroblastic tumor: A case report

•This is the first case report of inflammatory myofibroblastic tumor in the literature to present with extrauterine disease.•A prompt work-up of symptoms may have precluded a tumor debulking procedure.

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).

Successful treatment of recurrent pediatric inflammatory myofibroblastic tumor in a single patient with a novel chemotherapeutic regimen containing celecoxib

Inflammatory myofibroblastic tumors are rare tumors characterized as low-to-intermediate grade sarcomas. This is a case of a 7-year-old male with a 5-cm lung mass, which recurred 11 months after complete resection. The recurrence manifested as multifocal metastatic disease involving the ipsilateral parietal and visceral pleura. A novel chemotherapeutic regimen, which included vincristine, ifosfamide, doxorubicin, and celecoxib was utilized for the disease recurrence. The patient had complete and durable remission of the disease and has been disease-free for >4 years. This novel regimen including a cyclooxygenase 2 inhibitor may be an effective regimen for metastatic inflammatory myofibroblastic tumors.

Adult intestinal intussusception caused by an inflammatory myofibroblastic tumor

Inflammatory myofibroblastic tumor (IMT), which usually affects young adults and children, is a solid neoplastic mesenchymal proliferation composed of myofibroblastic spindle cells admixed with inflammatory infiltrates. Numerous extrapulmonary sites of these tumors have been found, but intestinal IMT is rare, especially in elderly patient. Its diagnosis is recognized as difficult because the patients usually do not have a specific symptom. Here, we present the case of a 79-year-old man with an IMT that caused small intestinal intussusception, which was diagnosed by abdominal ultrasonography. We review the literature on IMT and specially focus on the diagnostic modalities for this disease.

Inflammatory myofibroblastic tumor of parotid in infancy--a new entity

Inflammatory myofibroblastic tumor is commonly found in lungs, mesentery or omentum in the younger population. We hereby report a hitherto unreported case of inflammatory myofibroblastic tumor, arising from the parotid gland in an infant. Diagnosis by histopathology and its treatment by superficial parotidectomy is being presented.

Colonic inflammatory myofibroblastic tumours: an institutional review

AIM

The aim of the study was to present the largest series of colonic inflammatory myofibroblastic tumour (C-IMFT) in the literature so far and to provide a review of this condition.

METHOD

A retrospective review was carried out of a consecutive series of patients diagnosed with a C-IMFT at a community-based hospital with a specialized gastrointestinal unit between 2002 and 2011. The main outcome measures were success rate and postoperative complications. Using a set of terms we searched the PubMed database for papers published on C-IMFT. We reviewed the data from these studies and case reports.

RESULTS

There were seven patients with a histopathologically proven C-IMFT. The patients' mean age was 39 ± 11.3 years. Four presented with clinical features of intestinal obstruction of varying severity and three with symptoms of anaemia. Complete surgical resection with end-to-end anastomosis was performed. The gross morphology included polypoidal myxoid tumours that served as a lead point for intussusception in two cases, a whorled mass in two and a circumferential infiltrative tumour in three. Microscopically, all tumours had typical features of IMFT with a variable expression of anaplastic lymphoma kinase (ALK-1) and tumour-free resection margins. All patients were well without local recurrence or metastasis at a mean follow-up of 46.8 ± 11.9 months.

CONCLUSION

Surgical resection is effective for this rare tumour which mostly behaves in a benign manner. Our review supports the need for patients to be followed up for long periods because of the possibility of metastasis or late recurrence.

Inflammatory myofibroblastic tumor: a rare tumor in the tongue

Inflammatory myofibroblastic tumor is composed of myofibroblast and inflammatory cell infiltration of the tissue. Malign transformation and recurrence rate of this tumor is rare and accepted as benign fibroinflammatory disease. The main etiology is unclear, but infection, trauma, and immunologic event are accused. In this study, we presented a 75-year-old man with a mass on his tongue, which was diagnosed as “inflammatory myofibroblastic tumor.” This type of tumor is rarely seen in the tongue and might be difficult to diagnose. Complete mass excision was provided for an adaquete treatment.

Complete remission of ALK-negative plasma cell granuloma (inflammatory myofibroblastic tumor) of the lung induced by celecoxib: A case report and review of the literature

We report a case in which a 52-year-old female developed a multifocal inflammatory myofibroblastic tumor (IMT) of the lung. The tumor did not overexpress the anaplastic lymphoma kinase (ALK) protein, indicating a lack of ALK rearrangement. The patient required two wedge resections in 15 months due to recurrent disease. Recurrence after the second surgery was treated with corticosteroids, which only led to a transient response (6 months). Introduction of celecoxib, a cyclooxygenase-2 inhibitor, induced a complete remission in the patient. Maintenance on celecoxib further led to a progression-free survival of 34 months. A literature review retrieved a total of eight case reports, comprising ten patients, of IMT of various anatomical sites successfully treated with non-steroidal anti-inflammatory agent (NSAID) therapy. Nine of the ten patients achieved durable complete remission. Remission occurred rapidly and persisted even after termination of NSAID therapy. Although such a successful outcome may only be achieved rarely, a trial of an NSAID should be considered in any patient in whom complete resection is not an option. Our case also demonstrates that NSAID therapy may be successful in a non-ALK rearranged tumor in which ALK inhibition is not an option.

Primary inflammatory myofibroblastic tumor of the stomach in an adult woman: a case report and review of the literature

Inflammatory myofibroblastic tumor has been defined as a histologically distinctive lesion with uncertain behaviour. The term inflammatory myofibroblastic tumor more commonly referred to as "pseudostumor ", denotes a pseudosarcomatous inflammatory lesion that contains spindle cells, myofibroblasts, plasma cells, lymphocytes and histiocytes. It exhibits a variable biological behavior that ranges from frequently benign lesions to more aggressive variants. Inflammatory myofibroblastic tumor mostly occurs in the soft tissue of children and young adults, and the lungs are the most commonly affected site, but it has been recognized that any anatomic localization can be involved. Inflammatory myofibroblastic tumors in adults are very rare, especially in the stomach. We present a case of a 43-year old woman with primary inflammatory myofibiroblastic tumor in the stomach and a review of the literature.

An inflammatory myofibroblastic tumour of the breast with ALK overexpression

Inflammatory myofibroblastic tumours (IMTs), also known as inflammatory pseudotumours, include a diverse group of lesions characterised by inflammatory cell infiltration and variable fibrotic responses. Their occurrence in the breast is unusual. We present a case of an IMT of the breast in a 46-year-old woman who complained of a breast mass with palpable axillary lymph node. The initial clinical diagnosis was breast cancer, and the patient underwent a conservative excision with apparently negative margins and an axillary lymph node excisional biopsy. A histopathological examination showed the presence of myofibroblastic spindle cells with mixed inflammatory infiltrates, and the pathological diagnosis was IMT. Significantly, the case we present here is unique in showing anaplastic lymphoma kinase 1 (ALK1) overexpression and ALK1 gene amplification in IMT of the breast. Therefore, our case suggests that ALK1 gene amplification in IMT of the breast has important diagnostic and therapeutic implications.

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.

Molecular Pathology of Sarcoma

The rapid growth of tissue-based molecular pathology has changed the practice of the surgical pathologist signing out soft tissue tumors. This information is presented in a practical and succinct manner focusing on clinically validated findings that have diagnostic or therapeutic relevance. The approach is morphologically based and focuses on differential diagnoses and clinical scenarios. Molecular techniques can be an invaluable ancillary tool.

A rare case of an inflammatory myofibroblastic tumor in a middle-aged female

Inflammatory myofibroblastic tumors (IMTs) are distinct entities with specific characteristics immunohistochemically and molecularly. They are regarded as “intermediate malignancy” tumors of unknown etiology. We report a case of a 64-years-old woman with a fever and abdominal discomfort for 3 months; a computer tomography was performed indicating gastrointestinal stromal tumor. Histologically the lesion proved to be IMT of the abdomen.

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 myofibroblastic tumour of the maxillary sinus: CT and MRI findings

AIM

To characterize the computed tomography (CT) and magnetic resonance imaging (MRI) findings of inflammatory myofibroblastic tumours (IMTs) of the maxillary sinus.

MATERIALS AND METHODS

The imaging findings of eight patients with IMTs of the maxillary sinus were reviewed retrospectively. Of the eight patients, four patients underwent unenhanced and contrast-enhanced CT, and one patient underwent unenhanced CT only; three patients underwent unenhanced and contrast-enhanced MRI.

RESULTS

Five cases of IMTs occurred in the left maxillary sinus, while three cases were right-sided. Four cases occupied the entire sinus, and the other four cases only partially occupied the sinus. Unenhanced CT images showed heterogeneous masses in four cases and a homogeneous mass in one case. One of the tumours showed some areas of calcification. T1-weighted MRI images showed isointense lesions. T2-weighted images showed mixed isointense and mild hyperintense lesions. All cases showed bone destruction and had infiltrated into the nasal fossa, orbit, infratemporal fossa, and other adjacent tissues. Seven cases showed mild to moderate heterogeneous enhancement on contrast-enhanced CT or T1-weighted MRI images.

CONCLUSION

IMTs of the maxillary sinus can be characterized as a soft-tissue mass with bony destruction and infiltration of the adjacent tissues, with mild to moderate enhancement after the injection of contrast medium. CT and MRI can help to diagnose IMTs, determine the extent of the lesion and its relationship with adjacent tissues, and thus facilitate the prediction of surgical resectability.

Inflammatory myofibroblastic tumor of spermatic cord

INTRODUCTION

Inflammatory myofibroblastic tumor (IMT) is a neoplasm of intermediate biologic potential. Only a few cases of IMT in the spermatic cord have been reported. It was earlier included in a wide spectrum of reactive and neoplastic lesions called "inflammatory pseudotumors". It commonly presents as a painless scrotal mass, usually in children and young adults.

PRESENTATION OF CASE

We present a case of IMT in the spermatic cord who based on clinical, radiological and cytological findings underwent surgical exploration of left scrotal sac. The mass was separate from the left testis and left epididymis, and was closely adherent to pampiniform plexus of veins. Wide excision of the mass was done. Histology and immunohistochemistry suggested IMT.

DISCUSSION

IMT is a myofibroblastic spindle cell proliferation with chronic inflammatory infiltrate. Surgical exploration is essential as clinically and radiologically benign or malignant nature of mass cannot be distinguished. The diagnosis of IMT is based on the histological features and is substantiated by immunomarkers.

CONCLUSION

In clinically distinct masses, based on frozen section, either tumor excision or radical orchidectomy can be performed. The prognosis is excellent after complete surgical excision of spermatic cord IMT. Careful long-term follow-up is essential, because of the possibility of recurrence, though rare in this site.

Anaplastic lymphoma kinase-directed therapy in inflammatory myofibroblastic tumors

PURPOSE OF REVIEW

Inflammatory myofibroblastic tumors (IMTs) are indolent mesenchymal neoplasms associated with a small risk of aggressive behavior and metastasis. Surgery is the mainstay of treatment and until recently there have been limited effective treatment options for unresectable disease. This review describes the identification of anaplastic lymphoma kinase (ALK) fusion genes in approximately 50% of IMTs and the role of ALK inhibition in the treatment of this disease.

RECENT FINDINGS

A recent phase I dose-escalation trial of the selective MET/ALK inhibitor crizotinib showed a long-term partial response in a patient with IMT carrying an ALK translocation but not in a patient with ALK-negative disease. Emergence of resistance to crizotinib occurs approximately 5-8 months after initiation of therapy and has been shown to be driven by different mechanisms. Multiple second-generation ALK inhibitors are currently being investigated in the preclinical and clinical trial setting.

SUMMARY

ALK-directed therapy has emerged as a highly effective treatment option for a subset of patients with IMT and pulmonary adenocarcinoma. A number of additional malignancies, including rhabdomyosarcoma, neuroblastoma, anaplastic large cell lymphoma, renal cell carcinoma, and inflammatory breast cancer, have been shown to activate ALK expression by means of ALK fusion proteins, ALK mutations, or increased ALK copy number. Development of more selective ALK inhibitors, which can overcome emergent crizotinib resistance mutations, as well as development of combination treatments with drugs targeting compensatory pathways, will be key to achieving therapeutic success in targeting this potent and prevalent oncogenic driver.

Pathology of gastrointestinal stromal tumors

Gastrointestinal stromal tumor (GIST) is a well recognized and relatively well understood soft tissue tumor. Early events in GIST development are activating mutations in KIT or PDGFRA, which occur in most GISTs and encode for mutated tyrosine receptor kinases that are therapeutic targets for tyrosine kinase inhibitors, including imatinib and sunitinib. A small minority of GISTs possessing neither KIT nor PDGFRA mutations may have germline mutations in SDH, suggesting a potential role of SDH in the pathogenesis. Immunohistochemical detection of KIT, and more recently DOG1, has proven to be reliable and useful in the diagnosis of GISTs. Because current and future therapies depend on pathologists, it is important that they recognize KIT-negative GISTs, GISTs in specific clinical contexts, GISTs with unusual morphology, and GISTs after treatment. This review focuses on recent developments in the understanding of the biology, immunohistochemical diagnosis, the role of molecular analysis, and risk assessment of GISTs.

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.

Fusion of dynactin 1 to anaplastic lymphoma kinase in inflammatory myofibroblastic tumor

Inflammatory myofibroblastic tumor is an uncommon neoplasm that occurs more often in younger patients. Approximately 50% of inflammatory myofibroblastic tumors are characterized by anaplastic lymphoma kinase fusion genes, more commonly TPM3-anaplastic lymphoma kinase and TPM4-anaplastic lymphoma kinase. Herein, we report a novel fusion of dynactin 1 to anaplastic lymphoma kinase in a neck inflammatory myofibroblastic tumor diagnosed in a 7-year-old girl. Histologic evaluation showed a perineurioma-like bland spindle cell neoplasm with positive immunohistochemical staining for anaplastic lymphoma kinase, S-100, and CD34 but negative for epithelial membrane antigen. Standard cytogenetic analysis showed a der(2)t(2;12)(p23;q11). Fluorescence in situ hybridization demonstrated separation of the anaplastic lymphoma kinase locus. 5'-rapid amplification of complementary DNA ends polymerase chain reaction identified an in-frame fusion of dynactin 1 exon 16 on chromosome 2 to anaplastic lymphoma kinase exon 20. Reverse transcription-polymerase chain reaction with specific primers and direct sequencing confirmed the fusion. The structure of the fusion protein retains the cytoskeleton-associated protein-glycine domain and coiled coil domain of dynactin 1 and the receptor tyrosine kinase domain of anaplastic lymphoma kinase. This novel fusion gene is structurally similar to other previously described anaplastic lymphoma kinase fusion genes and may be associated with the unusual morphology and immunophenotype of this tumor.

A case of inflammatory myofibroblastic tumor originated from the greater omentum in young adult

Inflammatory myofibroblastic (IMF) tumor is a rare solid tumor that often affects children. IMF tumors occur primarily in the lung, but the tumor may affect any organ system with protean manifestations. A 22-year-old woman was evaluated for palpable low abdominal mass that had been increasing in size since two months prior. Abdominal computed tomography showed a lobulated, heterogeneous contrast enhancing soft tissue mass, 6.5 × 5.7 cm in size in the ileal mesentery. At surgery, the mass originated from the greater omentum laying in the pelvic cavity and was completely excised without tumor spillage. Histologically, the mass was a spindle cell lesion with severe atypism and some mitosis. Immunohistochemistry for anaplastic lymphoma kinase-1 revealed that the lesion was an IMF tumor. Because of its local invasiveness and its tendency to recur, this tumor can be confused with a soft tissue sarcoma. Increasing physician awareness of this entity should facilitate recognition of its clinical characteristics and laboratory findings.

Inflammatory myofibroblastic tumor of the lung in children: anaplastic lymphoma kinase (ALK) expression and clinico-pathological correlation

The inflammatory myofibroblastic tumor (IMT) is a rare neoplastic lesion with a high incidence in children and young people, and may arise in lungs, soft tissue, or viscera. It is recognized as a borderline tumor with the possibility to recur, undergo malignant transformation, and metastasize. IMT is composed of fascicles of bland myofibroblastic cells admixed with an inflammatory infiltrate consisting of lymphocytes, plasma cells, and eosinophils. We reviewed pulmonary IMT diagnosed at Garrahan Hospital in Buenos Aires, Argentina, during 12 years and examined the clinical, laboratory, and pathological features as well as molecular genetics. Eight pediatric cases were evaluated with a male-to-female ratio of 5:3 and a median age of 6 years at diagnosis. The most common lung localization was the upper lobe. All cases underwent surgical excision and no local recurrences were found. Five out of eight patients, including two cases with metastatic/multifocal lesions in the central nervous system (CNS), are alive and disease free after a median follow-up of 30 months. Anaplastic lymphoma kinase (ALK) expression was negative in all pulmonary samples by immunohistochemistry (IHC), however, rearrangement for ALK locus by fluorescence in situ hybridization was found in one lung and in two CNS samples. These findings may reflect higher sensitivity of the molecular biologic procedure compare to traditional IHC practice. In our pediatric experience, 25% of patients with lung IMT developed CNS lesions; therefore we consider that CNS screening in these patients should be considered, at diagnosis and later during follow up.

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.

Etiology analysis and computed tomography imaging of a tonsillar inflammatory myofibroblastic tumor: report of an immunocompetent patient and brief review

Objectives

The etiology of Inflammatory myofibroblastic tumor(IMT) is contentious. In this study, we used computed tomography (CT) to examine tonsillar IMT and further analyzed the etiology of this entity.

Methodology

We presented CT features of left tonsillar IMT and reviewed the English-language literature published between 1984 and 2011.

Results

To our knowledge, there are only six published cases of tonsillar IMT including the present case. Two patients were asymptomatic at initial presentation. Two patients were taking immunosuppressants, and one was pregnant and in an immunomodulated state. CT of our patient revealed a 2.6 × 1.8 cm irregular soft tissue mass between the left tonsil and the base of the tongue. It did not invade surrounding structures and was not enhanced on contrast-enhanced imaging.

Conclusions

Tonsillar IMT may be a benign tumor. We suggest that preoperative recognition of tonsillar IMT by CT may be important to avoid unnecessary expanded surgery.

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.

Anaplastic Lymphoma Kinase Aberrations in Rhabdomyosarcoma: Clinical and Prognostic Implications

Purpose

The aim of this study is to investigate anaplastic lymphoma kinase (ALK) protein expression and underlying genetic aberrations in rhabdomyosarcoma (RMS), with special attention to clinical and prognostic implications.

Patients and Methods

A total of 189 paraffin-embedded RMS tumor specimens from 145 patients were collected on tissue microarray. ALK protein expression was evaluated by immunohistochemistry. ALK gene (2p23) copy number and translocations were determined by in situ hybridization. cDNA sequencing of the receptor tyrosine kinase domain of the ALK gene was assessed in 43 samples.

Results

Strong cytoplasmic ALK protein expression was more frequently observed in alveolar RMS (ARMS) than in embryonal RMS (ERMS) (81% v 32%, respectively; P < .001). ALK gene copy number gain was detected in the vast majority of ARMS (88%), compared with 52% of ERMS (P < .001). ALK copy number correlated with protein expression in primary tumors (n = 107). We identified one point mutation (2%) and seven tumors harboring whole exon deletions (16%). In ERMS, specific ALK gain in the primary tumor correlated with metastatic disease (100% in metastatic disease v 29% in nonmetastatic disease; P = .004) and poor disease-specific survival (5-year disease-specific survival: 62% v 82% for nonspecific or no gain; P = .046).

Conclusion

Because ALK aberrations on genomic and protein levels are frequently found in RMSs, in particular ARMS, and are associated with disease progression and outcome in ERMS, ALK may play a role in tumor biology and may provide a potential therapeutic target for these tumors. Future research should aim at the oncogenic role of ALK and the potential effect of ALK inhibitors in RMS.

Synchronous gastric inflammatory myofibroblastic tumour with gastrointestinal stromal tumour of the stomach and hepatic syringious haemangioma

Inflammatory myofibroblastic tumour of the stomach is a very rare lesion. A case of a gastric inflammatory myofibroblastic tumour associated with gastrointestinal stromal tumour of the stomach and hepatic syringious haemangioma is described. We report an 80-year-old male who had an exophytic mass in the area of the pylorus and the duodenum, where hepatic cysts were found in the magnetic resonance (MRI) scan on examination of hypochromic microcytic anaemia, and prolapsus and torsion of the bulb of the stomach found during gastroscopy. During surgical excision of the exophytic mass, a gastrointestinal stromal tumour from the gastric fundus and a syringious haemangioma from the superior hepatic surface were resected. All tumours were treated successfully by surgical excision. The patient had an uneventful recovery. Neither recurrence nor metastasis was found after a 12-month follow-up. To our knowledge, this is the first time that such an association is reported in the literature.

Carboplatin plus paclitaxel in the successful treatment of advanced inflammatory myofibroblastic tumor

A 26-year-old man with unresectable inflammatory myofibroblastic tumor (IMT) presented with multiple metastases in the thoracic vertebra and lymph nodes as detected by positron emission tomography (PET) received chemotherapy with carboplatin plus paclitaxel. After three cycles of chemotherapy, fluorine-18-fluorodeoxyglucose (FDG)-PET/CT revealed tumor regression and significant reduction of FDG uptake in all lesions. The patient received six cycles of chemotherapy without any severe adverse event, and there was no sign of disease progression for seven months. This regimen is well tolerated and may be considered the treatment of choice for unresectable IMT.

Targeted therapy in sarcoma: should we be lumpers or splitters?

The identification of KIT as a critical driver in the pathogenesis of GI stromal tumor (GIST), and its subsequent inhibition with imatinib, have resulted in tremendous efforts to identify other potential therapeutic targets for the heterogeneous group of diseases known as sarcomas. Because of the rarity of sarcoma and the often limited number of patients per individual sarcoma subtype, clinical trials to date have often utilized unselected patient populations including multiple subtypes. Although this strategy increases the ease with which a particular trial may accrue patients, statistically significant therapeutic responses across an unselected patient population are often limited. Furthermore, in the absence of biologic correlatives, the identification of significant activity and subsequent interpretation of clinical trial results utilizing targeted therapies for this patient population have been challenging. However, hints have emerged, on the basis of preclinical and clinical observations, to suggest that certain targeted therapeutic approaches are appropriate in select histologic subtypes. This brief review will highlight data supporting the use of targeted therapy in both unselected and selected sarcoma patient populations.

Pediatric fibroblastic and myofibroblastic lesions

Fibrous lesions of infancy and childhood are a heterogeneous group of entities composed predominantly of fibroblasts and myofibroblasts, ranging from reactive lesions to neoplasms with a range of malignant potential. Although rare, their correct recognition by histopathology is important clinically as they exhibit a wide range of behaviors and may be associated with distinct underlying syndromes. Contributions from molecular diagnostics have enabled more accurate diagnosis, and have changed our concepts of some tumor types. In this review, we discuss the clinicopathologic spectrum of fibroblastic and myofibroblastic lesions of childhood and adolescence.

Inflammatory myofibroblastic tumor in colon

Inflammatory myofibroblastic tumor (IMT) is an uncommon mesenchymal solid tumor commonly documented in children and young adults. Here, we report a case of IMT in colon confirmed pathologically after laparoscopic anterior resection. A 35-year-old man presented with anal bleeding after defecation for 2 weeks. Colonoscopy demonstrated a mass with shallow ulceration in the central area and irregular margin accompanied by intact mucosa in the descending colon. Computer tomography showed a well-demarcated and homogenous solitary mass in the descending colon. We performed laparoscopic anterior resection. This case was diagnosed as IMT after microscopic examination. The tumor was composed of a proliferation of spindle-shaped cells arranged in the hyaline material with chronic inflammatory cells, composed mainly of plasma cells and lymphocytes. Immunohistochemically, tumor cells were positive for smooth muscle actin, and vimentin, and negative for desmin, CD117 (c-kit), anaplastic lymphoma kinase-1.

Aggressive hilar inflammatory myofibroblastic tumor with hilar bile duct carcinoma in situ

Inflammatory myofibroblastic tumor (IMT) of the biliary tree is extremely rare and is generally a benign condition, though malignant change is possible. Making a differential diagnosis between this lesion and other malignant conditions is very difficult on preoperative imaging studies. Hence, the final diagnosis of IMT may be made during or after operation depending on the pathologic examination. We treated a 63-year-old woman who received right hepatectomy with caudate lobectomy under the suspicion of hilar cholangiocarcinoma. Frozen biopsy during the operation showed carcinoma in situ and there were stromal cells in the bile duct's resection margins. The postoperative hospital course was uneventful except for minor bile leakage. At postoperative month 4, she developed jaundice, ascites and pleural effusion. Computed tomography images showed a mass-like lesion in the porta hepatis with portal vein thrombosis and a right chest wall mass. Excisional biopsy was done and the pathology report was malignant spindle cell tumor suggestive of an aggressive form of IMT. Her condition rapidly deteriorated regardless of the best supportive care and she expired at postoperative month 5. Further investigation is necessary to clarify the reasons for recurrence and infiltration of this disease.

The potential for crizotinib in non-small cell lung cancer: a perspective review

Tyrosine kinases have a crucial role as key regulators of signaling pathways that influence cell differentiation and growth. Dysregulation of tyrosine kinase-mediated signaling is understood to be an important oncogenic driver. Genetic rearrangements involving the tyrosine kinase anaplastic lymphoma kinase (ALK) gene occur in non-small cell lung cancer (NSCLC), anaplastic large cell lymphomoas, inflammatory myofibroblastic tumors, and other cancers. Cells with abnormal ALK signaling are sensitive to ALK inhibitors such as crizotinib. This review will highlight the discovery of the fusion between echinoderm microtubule-associated protein-like 4 (EML4) and ALK as an oncogenic driver, recognition of other ALK gene rearrangements in NSCLC, and the confirmation that crizotinib is an effective treatment for patients with ALK-positive NSCLC. Work is underway to further define the role for crizotinib in the treatment of ALK-positive lung cancer and other cancers and to investigate the molecular mechanisms for resistance to ALK inhibition with crizotinib.

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.