The relationship between pseudotumours and infected complications in patients who have undergone metal-on-metal total hip arthroplasty.

Aims: This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection. Methods: A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years' clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery. Results: The rate of PJI for all identified MoM THAs was 3.5% (41/1,171), with a mean follow-up of 10.9 years (2.0 to 20.4). Of the patients included in the final cohort, 8.2% (27/328) had PJI, with a mean follow-up of 12.2 years (2.3 to 20.4). Among this cohort, 31.1% (102/328) had a history of pseudotumour. The rate of PJI in these patients was 14.7% (15/102), which was greater than those without pseudotumour, 5.3% (12/226) (p = 0.008). Additionally, logistic regression analysis showed an association between history of pseudotumour and PJI (odds ratio 4.36 (95% confidence interval 1.77 to 11.3); p = 0.002). Optimal diagnostic cutoffs for PJI in patients with history of pseudotumour versus those without were 33.1 mm/hr and 24.5 mm/hr for ESR and 7.37 mg/dl and 1.88 mg/dl for CRP, respectively. Conclusion: Patients with history of pseudotumour secondary to MoM THA had a higher likelihood of infection than those without. While suspicion of infection should be high for these patients, ESR and CRP cutoffs published by the European Bone and Joint Infection Society may not be appropriate for patients with a history of pseudotumour, as ESR and CRP levels suggestive of PJI are likely to be higher than for those without a pseudotumour. Additional investigation, such as aspiration, is highly recommended for these patients unless clinical suspicion and laboratory markers are low.

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.

EBER-negative inflammatory pseudotumor-like follicular dendritic cell sarcoma of liver: A case report.

RATIONALE: Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) of the liver is rare. It was previously believed that Epstein-Barr virus (EBV) positivity was a necessary criterion for pathological diagnosis. However, we found that there were also cases of EBV negativity. Therefore, clinicians and pathologists are reminded that EBV positivity is not a necessary condition for diagnosis. PATIENT CONCERNS: A 70-year-old female underwent computed tomography (CT) examination for upper abdominal discomfort, which revealed the presence of a liver tumor. Follow-up revealed that the tumor had progressively increased in size. DIAGNOSIS: The final diagnosis was an IPT-like follicular cell sarcoma, based on CT, MRI, HE staining, and immunohistochemical staining. INTERVENTIONS: The patient underwent a laparoscopic left hemihepatectomy. OUTCOMES: The patient has not undergone any special treatment, such as radiotherapy and chemotherapy, and has been followed up for over 3 years without experiencing any recurrence. LESSONS: IPT-like FDCS is a rare tumor that lacks definitive criteria, and its diagnosis mainly relies on pathological findings. Previously, it was believed that being EBV-positive was an important condition for diagnosis. Primary IPT-like FDCS in the liver is even rarer, and the patient in this case tested negative for EBV. It may be necessary for pathologists to consider the role of EBV in the diagnosis of IPT-like FDCS.

Rare cardiac inflammatory pseudotumor in a toddler: Complementary roles of cardiac magnetic resonance and positron emission tomography.

We present a rare pediatric case of cardiac inflammatory pseudotumor (IPT) with a unique presentation of fever of unknown origin with markedly elevated inflammatory markers. A right atrial mass was discovered incidentally by echocardiography. The cardiac magnetic resonance (CMR) signal characteristics and mass location were not consistent with any of the common benign cardiac tumors of childhood. The presence of high signal intensity on T2 imaging and late gadolinium enhancement, in conjunction with intense metabolic activity at the mass site on positron emission tomography (PET), raised the possibility of an inflammatory or malignant mass. The diagnosis of IPT was confirmed by biopsy. Our case highlights the utility of PET imaging to confirm the inflammatory nature and extent of an IPT.

Inflammatory myofibroblastic tumor directly invading the right first rib treated with oral steroids: a case report.

BACKGROUND: We present a case of an inflammatory myofibroblastic tumor cured with a short period of steroid administration, a treatment previously unreported for such cases. CASE PRESENTATION: A 49-year-old man had a chief complaint of chest pain for more than 3 days. Computed tomography (CT) revealed a tumoral lesion suspected to have infiltrated into the right first rib and intercostal muscles, with changes in lung parenchymal density around the lesion. The maximal standardized uptake value on 18 F-fluorodeoxyglucose positron emission tomography/computed tomography was high (16.73), consistent with tumor presence. CT-guided biopsy revealed an inflammatory myofibroblastic tumor with no distant metastases. Surgery was indicated based on the disease course. However, he had received an oral steroid before the preoperative contrast-enhanced CT scan due to a history of bronchial asthma, and subsequent CT showed that the tumor shrank in size after administration; he has been recurrence-free for more than a year. CONCLUSIONS: Surgery is still the first choice for inflammatory myofibroblastic tumors, as the disease can metastasize and relapse; however, this condition can also be cured with a short period of steroid therapy.

Epstein-Barr virus-positive inflammatory follicular dendritic cell sarcoma with significant granuloma: case report and literature review.

BACKGROUND: Epstein-Barr virus-positive inflammatory follicular dendritic cell sarcoma (EBV+IFDCS) is a rare disease characterized by mild clinical symptoms and non-specific imaging findings. The diagnosis of the disease depends on pathological diagnosis. However, EBV+IFDCS has a very broad spectrum of histological morphology and immune phenotypes, and its histopathological features have not been fully described by pathologists. CASE PRESENTATION: A 59-year-old female, with no significant discomfort, was found to have a splenic mass during a routine physical examination. Microscopic examination at low magnification revealed numerous epithelioid granulomas, amidst which a substantial inflammatory response was observed. Interspersed among the dense inflammatory cells were spindle or oval-shaped cells, distributed sporadically with indistinct boundaries. Under high magnification, these spindle cells had subtle features: smooth and clear nuclear membranes, inconspicuous small nucleoli, and infrequent mitotic figures. Immunophenotypically, the spindle cells expressed CD21 and CD23, and Epstein-Barr encoding region (EBER) in situ hybridization yielded positive results. The inflammatory milieu predominantly consisted of T cells, with a minority of plasma cells expressing IgG4. The confluence of morphological and immunohistochemical findings led to the final pathological diagnosis of EBV+IFDCS in this case. CONCLUSIONS: The presentation of EBV+IFDCS with pronounced granulomatous changes is rare. This morphological variant poses a high risk of misdiagnosis, frequently leading to confusion with other granulomatous diseases. Accurate diagnosis necessitates a comprehensive analysis, integrating immunohistochemistry and in situ hybridization. The case presented here is instrumental in raising awareness and understanding of EBV+IFDCS, with the goal of reducing misdiagnoses and unrecognized cases.

A rare inflammatory myofibroblastic tumor appearing both inside and outside the heart.

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) is an uncommon cardiac tumor that primarily affects infants, children, and young adults. While complete surgical resection generally leads to a favorable prognosis, accurate diagnostic tests remain limited. CASE PRESENTATION: We describe the case of a 26-year-old female who had a dual tumor inside and outside the heart and was misdiagnosed by echocardiography and MRI. We also review 71 cases of cardiac IMTs from the literature regarding their epidemiology, clinical presentation, and outcome. CONCLUSION: Early detection of this rare disorder is essential for optimal surgical management.

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.

[A case of inflammatory myofibroblastic tumor with rapidly progressive growth arising from the retroperitoneum].

A woman in her 70s was admitted to our institution with complaints of right hypochondrium pain. Abdominal computed tomography revealed a 13-mm retroperitoneal tumor between the liver and right kidney. The tumor rapidly increased to 82mm within 2 months, a necrotic change was inside the tumor, and the inflammation spread to the surrounding diaphragm and the peritoneum. The patient underwent surgical resection including the affected diaphragm and the peritoneum. Histopathological examination revealed a myofibroblastic spindle-cell proliferation with prominent infiltration of inflammatory cells, such as the plasma cells, lymphocytes, neutrophils, and eosinophils, diagnosed as an inflammatory myofibroblastic tumor (IMT) based on positive smooth muscle actin staining. IMT arising from the retroperitoneum is a rare case in Japan;we report this case with literature review.

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.

A case of inflammatory myofibroblastic tumor harboring EML4-ALK fusion with a brain metastasis responding to alectinib.

Metastatic inflammatory myofibroblastic tumor (IMT) is very rare and detailed reports on diagnosis and treatment are limited. Here, we report a case of metastatic IMT with ALK rearrangement. A 73-year-old woman was diagnosed with IMT involving a brain metastasis. Next generation sequencing (NGS) panel testing with Oncomine dx target test revealed that her tumor was positive for EML4-ALK. Treatment with alectinib was initiated, resulting in remarkable shrinkage of both the primary tumor and the brain metastasis. This report is the first to identify ALK rearrangement in IMT using a commercially available NGS panel testing, followed by treatment with alectinib. This case suggests that NGS panel testing may be useful in the diagnosis and treatment of patients with metastatic IMT.

Ocular inflammatory myofibroblastic tumor in a pediatric patient.

Inflammatory myofibroblastic tumor (IMT) is a mesenchymal neoplasm that rarely metastasizes and is more commonly seen in children, adolescents, and young adults than older adults. These tumors, composed of myofibroblasts and inflammatory cells, are often confused for a local infection due to the inflammatory cell infiltration, and they form in mucosal surfaces but rarely arise in the orbit. We present the case of a 6-year-old girl with excisional biopsy-confirmed conjunctival stromal IMT. There was no evidence of recurrence 2 years following resection with no subsequent medical therapy.

A surgical case of inflammatory pseudotumor by hepatic anisakiasis.

Anisakiasis is a parasitic infection caused by the ingestion of raw or undercooked seafood infected with Anisakis larvae. It generally affects the gastrointestinal tract, particularly the stomach, but very rare cases have been reported in which infection of the liver leads to the formation of inflammatory pseudotumors. We herein report an extremely rare case of an inflammatory pseudotumor induced by hepatic anisakiasis that was laparoscopically resected for the purpose of both diagnosis and treatment. A 51-year-old woman underwent a routine medical checkup by ultrasound examination, which incidentally detected a 15-mm mass on the surface of S6 of the liver. Because a malignant tumor could not be ruled out on several preoperative imaging studies, laparoscopic partial resection of the liver was performed. Histopathological examination revealed Anisakis larva in the inflammatory pseudotumor, suggesting hepatic anisakiasis. This report describes an extremely rare case of an inflammatory pseudotumor induced by hepatic anisakiasis. Because the preoperative diagnosis could not be obtained by several imaging modalities, laparoscopic liver resection with a sufficient margin might be suitable for diagnosis and treatment of this disease.