A case report of IgG4-related hepatic inflammatory pseudotumor in a 3-year old boy.

Background: Hepatic Inflammatory Pseudotumor (IPT) is an infrequent condition often masquerading as a malignant tumor, resulting in misdiagnosis and unnecessary surgical resection. The emerging concept of IgG4-related diseases (IgG4-RD) has gained widespread recognition, encompassing entities like IgG4-related hepatic IPT. Clinically and radiologically, corticosteroids and immunosuppressive therapies have proven effective in managing this condition. Case Presentation: A 3-year-old Chinese boy presented to the clinic with an 11-month history of anemia, fever of unknown origin, and a tender hepatic mass. Blood examinations revealed chronic anemia (Hb: 6.4 g/L, MCV: 68.6 fl, MCH: 19.5 pg, reticulocytes: 1.7%) accompanied by an inflammatory reaction and an elevated serum IgG4 level (1542.2 mg/L). Abdominal contrast-enhanced computed tomography unveiled a 7.6 cm low-density mass in the right lateral lobe, while magnetic resonance imaging demonstrated slight hypointensity on T1-weighted images and slight hyperintensity on T2-weighted images, prompting suspicion of hepatic malignancy. A subsequent liver biopsy revealed a mass characterized by fibrous stroma and dense lymphoplasmacytic infiltration. Immunohistochemical analysis confirmed the presence of IgG4-positive plasma cells, leading to the diagnosis of IgG4-related hepatic IPT. Swift resolution occurred upon initiation of corticosteroid and mycophenolate mofetil therapies. Conclusion: This study underscores the diagnostic approach to hepatic IPT, utilizing histopathology, immunostaining, imaging, serology, organ involvement, and therapeutic response. Early histological examination plays a pivotal role in clinical guidance, averting misdiagnosis as a liver tumor and unnecessary surgical interventions.

Photodynamic therapy for cutaneous inflammatory pseudotumour: A case report.

Inflammatory pseudotumour (IP) is a rare proliferative disease characterized by a dense infiltrate of plasma cells, lymphocytes, eosinophils and neutrophils in the fibrous stroma. It primarily affects the lungs of pediatric patients or young adults. Cutaneous IP is an extremely rare condition, with limited documentation in the English literature. In this case report, we presented an unusual instance of a 62-year-old male endured recalcitrant cutaneous IP for 8 years and exhibited poor response to topical glucocorticoid therapy, as well as intralesional injections of pingyangmycin and/or corticosteroid. Notably, after undergoing four sessions of 5-aminolevulinic acid photodynamic therapy (ALA-PDT), the patient experienced a significant reduction in erythema and nodules. This observation suggests that ALA-PDT may represent a promising and safe treatment option for cutaneous IP.

The Potential Utility of 18 F-FDG PET/CT in Monitoring Corticosteroid Therapy in Inflammatory Pseudotumor.

ABSTRACT: A 69-year-old man with suspected gastrointestinal stromal tumor was referred to 18 F-FDG PET/CT. Images showed increased metabolism in a jejunal wall thickening, 2 liver lesions, and hepatic lymph nodes. The patient underwent wedge biopsy of the liver, which revealed inflammatory pseudotumor. The patient was treated with 20 mg/d prednisone, with a gradual dose reduction. A partial metabolic response was achieved after 2 months of therapy, and a final PET/CT showed complete metabolic response after 9 months. This clinical case shows the potential role of PET/CT in the assessment of the response of the inflammatory pseudotumor to corticosteroid therapy.

Crizotinib combined with bronchoscopic interventional treatment in ALK-positive inflammatory myofibroblastic tumor of left main stem bronchus: a case report.

BACKGROUND: Inflammatory myofibroblastic tumor (IMT), also known as an inflammatory pseudotumor, is a unique type of intermediate soft tissue tumor that commonly occurred in the lung. Its unclear etiology and cellular activity brought about the confusion not only in naming of it, but also in diagnosis and treatment. CASE PRESENTATION: We reported the case of an 18-year-old male student who suffered from shortness of breath, chest tightness and chest pain. Chest computed tomography scan showed a spherical neoplasm blocking left main stem bronchus. After fiberoptic bronchoscopy procedure, the results of histopathological and immunohistochemical analysis indicated an IMT. The targeted next generation sequencing based genomic profiling of the tumor using formalin-fixed and paraffin embedded tissue was performed and a EML4-ALK fusion was detected. The patient began to receive Crizotinib, a ALK tyrosine kinase inhibitor, at a dose of 250 mg twice daily orally. The patient has recovered well after the operation, and no recurrence or metastasis has been found after 12 months' follow-up. CONCLUSION: By means of the diagnosis and treatment of this case, the characteristics and therapies of IMT are illustrated. In addition, it also provides a reference for the therapeutic strategy of IMT in the future.

Inflammatory myofibroblastic tumors: recent progress and future of targeted therapy.

An inflammatory myofibroblastic tumor is a rare component of bone and soft-tissue sarcomas that has distinct pathological features as a lymphoplasmacytic inflammatory infiltrate. As is the case for other non-small round cell sarcomas, surgical resection remains the standard treatment strategy for inflammatory myofibroblastic tumors, but recurrence is possible. Concerning systemic therapy, the available data for conventional chemotherapy (such as those of doxorubicin-based regimens) are limited, and case reports of anti-inflammatory inflammatory myofibroblastic tumor treatments describe some degree of symptom relief and efficacy against tumor progression. However, as more information about cancer genomics accumulates, the potential for molecularly targeted therapies for inflammatory myofibroblastic tumors has become more promising. Approximately half of inflammatory myofibroblastic tumors harbor anaplastic lymphoma kinase (ALK) fusion genes, and the other half could have potentially targetable fusion genes or mutations such as ROS1, NTRK and RET; case reports demonstrating the clinical efficacy of treatments targeted to inflammatory myofibroblastic tumor have been published, as have several prospective clinical trials. Few drugs are approved for the treatment of inflammatory myofibroblastic tumor, and most of them were approved for tumor-agnostic indications. Drugs that could be used for pediatric indications and dosing in inflammatory myofibroblastic tumor have also not been established. To provide effective targeted therapy for rare diseases such as inflammatory myofibroblastic tumor, it is necessary to obtain clinical evidence by designing and performing clinical trials and to find a path toward regulatory approval.

Novel treatment of endobronchial inflammatory myofibroblastic tumor in a child.

Isolated endobronchial inflammatory myofibroblastic tumors (IMT) are rare, accounting for about 1% of primary endobronchial tumors in children. The mainstay of treatment for this tumor has been surgical resection. Recently, the identification of anaplastic lymphoma kinase (ALK) gene mutations in half of IMTs and promising results of treatment with ALK inhibitors in other ALK-positive tumors have opened the possibility of alternative approaches. We present a 4-year-old child with an ALK-positive endobronchial IMT, treated with endoscopic resection and neoadjuvant therapy with crizotinib, without evidence of tumor recurrence 2 years after the initial resection.

Fibrohistiocytic Variant of Hepatic Pseudotumor: An Antibiotic Responsive Tumefactive Lesion.

Inflammatory pseudotumor is a term used to designate inflammation-rich tumefactive lesions. Following the exclusion of specific entities such as IgG4-related disease and other neoplastic entities previously included in this entity, the majority of hepatic pseudotumors show a prominent fibrohistiocytic inflammatory reaction and have been previously categorized as fibrohistiocytic variant of hepatic pseudotumor (FHVHPT). The goal of this study was to examine the clinical, radiologic, histologic, and etiologic aspects of this entity. After excluding neoplastic diseases, we identified 30 patients with FHVHPT from 3 institutions between 2009 and 2019. We extracted demographic and clinical data, liver function tests as well as culture results and radiologic information. Hematoxylin and eosin-stained slides were reviewed for pattern of inflammation as well as its cellular composition. Immunohistochemistry for IgG4 and IgG was performed in all cases. The mean age of the 30 lesions characterized as FHVHPT was 56 years (range: 23 to 79 y). Nineteen patients showed solitary lesions; 11 were multiple. The mean size of the lesion was 3.8 cm (range: 1 to 7.5 cm). On imaging, a neoplastic process or metastasis was the leading diagnostic consideration (n=15, 50%). The most common symptom was abdominal pain (n=14/30); 8 patients presented with symptoms compatible with an infectious process, including fever. The inflammatory infiltrate was dominated by lymphocytes and plasma cells, and in most cases, a prominent histiocytic infiltrate (22/30). Neutrophils were identified in 12 cases, with microabscess noted in 8. Storiform pattern of fibrosis was seen in 14/30 cases; obliterative phlebitis was not identified. Culture identified a microorganism in 4 of 9 cases evaluated. The mean IgG4 count was 9.3 per HPF (range: 0 to 51) with 9 of the 26 (35%) biopsies showing >10 IgG4 positive plasma cells per HPF. The mean IgG4 to IgG ratio was 8% (range: 8% to 46%). A hepatectomy was performed in 4 cases. On broad spectrum antibiotics (n=14) the lesions either resolved or decreased in size. Eight patients did not receive specific therapy, nevertheless, the lesion(s) resolved spontaneously in 6 cases, remained stable or decreased in size in 2 cases. Notably, none of these patients showed evidence of a hepatic recurrence. FHVHPT, a tumefactive lesion that mimics hepatic neoplasia, is histologically characterized by a fibrohistiocytic infiltrate. In the majority of patients FHVHPT represents the organizing phase of hepatic abscess and can be successfully managed with antibiotic therapy.

Hepatic Inflammatory Pseudotumor Mimicking Malignant Tumor With Rare Onset of Intra-abdominal Hemorrhage.

BACKGROUND: Hepatic inflammatory pseudotumor (HIPT) is an uncommon benign tumor-like mass that mimics malignant tumors. CASE REPORT: A 73-year-old man was admitted with severe epigastric pain and high fever. He had received choledocojejunostomy. Enhanced computed tomography showed a 76 mm, heterogeneous, gradual enhanced low-density mass in the caudate lobe and hyperdense fluid was detected around the mass. Based on the diagnosis of hemorrhage from a hypervascular malignant liver tumor, chemoembolization was conducted. Antibiotics (Meropenem) were administered for 2 weeks, and methylprednisolone (125 mg) was administered twice as a premedication for chemoembolization. After the 2nd chemoembolization, rapid tumor shrinkage was observed and the inflammatory changes gradually disappeared. The tumor was finally diagnosed as fibrohistiocytic type HIPT with an ultrasound-guided percutaneous tumor biopsy. The diameter of the liver tumor decreased to 15 mm and intra-abdominal hemorrhage disappeared in 3 months. CONCLUSION: Development of HIPT can be associated with intra-abdominal hemorrhage.

Anaplastic lymphoma kinase inhibitor therapy in the treatment of inflammatory myofibroblastic tumors in pediatric patients: Case reports and literature review.

BACKGROUND: Inflammatory myofibroblastic tumors (IMTs) are a rare subtype of inflammatory pseudotumor frequently associated with rearrangement of the anaplastic lymphoma kinase (ALK) gene. Their treatment has historically relied on at-times challenging and morbid surgical excision. Recent studies have shown that neo/adjuvant therapy with ALK inhibitors can significantly enhance outcomes in select patients. METHODS: A systematic literature review was performed to characterize comprehensive treatment of ALK-positive IMTs in the pediatric population. This report also includes two patients from our home institutions not previously reported in the literature. RESULTS: We identified a total of 27 patients in 12 studies in addition to 2 patients from the senior authors' institution for a total of 29 patients (median age, 7 years; 52% male). The IMTs comprised a wide range of anatomic locations. Almost half (12, 41.3%) were treated with ALK-inhibitors alone and felt to be in remission. The remainder was treated with ALK-inhibitors either before or after surgery and had a curative response. CONCLUSIONS: ALK-positive IMTs can be successfully treated with ALK-inhibition alone or in combination with surgical resection. Further genetic characterization may be helpful in determining more precise treatment and defining needed durations thereof.

Esophageal inflammatory pseudotumor with low-dose corticosteroid therapy after surgery.

Inflammatory pseudotumors of the esophagus are extremely rare, and the treatment has been controversial. Herein, we report a case of esophageal inflammatory pseudotumor with low-dose corticosteroid treatment following surgery. A 50-year-old woman with a 3-month history of progressive dysphagia and weight loss, was admitted to our hospital for examination and treatment. Esophagography and endoscopic examination revealed a mass present from the cervical esophagus to the upper thoracic esophagus with severe esophageal stricture. Ultrasound-guided fine needle aspiration cytology, boring biopsy, and mucosal incision-assisted biopsy reveal chronic inflammation, but histological diagnosis was not proven. Surgery was performed to confirm diagnosis and to relieve esophageal stricture. However, because of dense adhesions around the tumor, complete tumor resection was not achieved. Histopathological examination showed an inflammatory infiltrate with plasma cells, eosinophils, neutrophils, and lymphocytes, suggesting an inflammatory pseudotumor. After surgical resection, the esophageal stricture remained, possibly due to the residual tumor. We used a postoperative low-dose steroid treatment that resulted in complete resolution. There has not been any evident sign of recurrence for more than 2 years.

Inflammatory pseudotumor-like follicular dendritic cell sarcoma of the liver.

A 53-year-old female with a history of HLA-B27 positive polyarthritis underwent a splenectomy due to an incidental splenic lesion, which was confirmed as an inflammatory pseudotumor (IPT). Afterwards, two liver lesions were found and histopathological examination revealed inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS). The patient received NSAIDs, corticosteroids, antibiotics and azathioprine, with no response. Within the next few months, there was an abrupt clinical worsening due to rapid progression of the hepatic lesions and a massive hepatomegaly. New biopsies were obtained, showing undifferentiated sarcoma. The patient started chemotherapy with doxorubicin and eventually died.

Lorlatinib for the treatment of inflammatory myofibroblastic tumour with TPM4-ALK fusion following failure of entrectinib.

Inflammatory myofibroblastic tumour (IMT) is a rare malignancy with limited responses to corticosteroids and chemotherapy. About half of cases have activating rearrangements in the ALK gene which could be targeted with ALK inhibitors. A 40-year-old man presented with a large right lung mass and nodal, trapezius and cerebral metastases. Biopsy confirmed IMT with TPM4-ALK fusion. He was treated with prednisolone without clinical benefit. He received the Trk/ROS1/ALK inhibitor entrectinib in a clinical trial but his disease progressed in less than 3 months. Ifosfamide and etoposide in addition to radiotherapy to the brain and chest were administered. Transient improvement in the radiotherapy-treated areas was observed but his disease progressed shortly afterwards on all sites including the development of new adrenal metastasis. Compassionate use of the third-generation ALK inhibitor lorlatinib resulted in excellent partial response on all disease sites after 2 months, followed by a further 6 months of disease stabilisation. Repeat imaging showed slight increase in size of the cerebral metastasis but stable disease elsewhere, for which he was given stereotactic radiotherapy. His disease progressed 3 months later and lorlatinib was substituted with another ALK inhibitor brigatinib but he deteriorated and died shortly afterwards. Our patient tolerated lorlatinib well for 11 months with minimal toxicities, although he developed unilateral right-sided lung consolidation that was probably related to a combination of infection, radiotherapy and lorlatinib, which needed treatment with antibiotics and corticosteroids. This case demonstrates a role of lorlatinib in the treatment of TPM4-ALK-rearranged IMT despite failure of entrectinib.

Inflammatory Demyelinating Pseudotumor With Liver Dysfunction: IgG4 Related Disease With Primary Biliary Cholangitis.

Immunoglobulin G4 related disease (IgG4-RD) is a recently recognized immune-mediated disease which is far from understanding. A case of inflammatory demyelinating pseudotumor had been confirmed as IgG4-RD according to pathology features and clinical context. Combined with liver dysfunction, IgG4 related sclerotic cholangitis was suspected. However, primary biliary cholangitis was finally diagnosed by immune marks and histopathological findings. This is the first report in which mass lesions in the brain parenchyma were caused by IgG4-RD while liver dysfunction was due to primary biliary cholangitis. The clinical features of IgG4-RD are miscellaneous, and the accumulation of case reports might enrich clinicians experience and broaden their horizons about this condition.

Hepatic Inflammatory Pseudotumor Protruding from the Liver Surface and Directly Penetrating the Colon.

A 69-year-old man was diagnosed with a liver abscess and received antibiotics at a local hospital. He was referred to our hospital due to a persistent fever. He had hepatic masses protruding from the liver surface toward the transverse colon. We reached a diagnosis of inflammatory pseudotumor (IPT) by a percutaneous liver biopsy. Colonoscopy showed direct invasion of IPT to the colon. His condition improved by the intravenous administration of antibiotics. Hepatic IPT is often misdiagnosed as a malignant tumor. We should consider IPT when we encounter hepatic tumors, and a percutaneous liver biopsy is useful for avoiding unnecessary excessive treatments.