Clinical Outcomes and Risk Factors for Re-Revision Due to Trunnion Corrosion in Primary Metal-on-Polyethylene Total Hip Arthroplasty.

BACKGROUND: There is a paucity of literature regarding the mid-term (greater than 2 years) outcomes of revision for adverse local tissue reaction to metal debris due to corrosion at the head-neck junction (trunnionosis) in metal-on-polyethylene total hip arthroplasty (THA), and risk factors for re-revision remain largely unknown. We aimed to report the re-revision-free survival and functional outcomes for this patient population and to identify risk factors for re-revision. METHODS: A total of 80 hips (79 patients) with a metal-on-polyethylene THA who had undergone revision for trunnionosis at our institution were included. The mean study follow-up from index trunnionosis revision was 4.6 years (range, 2.0 to 9.4). Kaplan-Meier survival analysis was performed with all-cause re-revision as the end point, and multivariate logistic regression was used to identify risk factors for re-revision. RESULTS: We saw that twenty-one hips (26%) underwent re-revision at a mean of 8.0 months (range, 0.03 to 36.3) after the index trunnionosis revision, most commonly for instability and infection. The two- and five-year all-cause re-revision-free survival rates were 75.0 and 73.2%, respectively. The mean Oxford Hip Score was 33.7 (range, 11 to 48); 76% were satisfied, and 24% were dissatisfied with their hip. Multivariate analysis identified not undergoing a cup revision (odds ratio: 4.5; 95% confidence interval: 1.03 to 19.7) and time from primary THA to the index trunnionosis revision (odds ratio: 0.77; 95% confidence interval: 0.62 to 0.97) as risk factors for undergoing re-revision. CONCLUSIONS: The risk of early re-revision for these patients is high (26%), mostly due to infection and instability, and functional outcomes are fair. Not performing a cup revision appears to be a risk factor for re-revision, as is the shorter time from primary THA to trunnionosis revision. LEVEL OF EVIDENCE: III.

Granulomatosis with polyangiitis presenting as a solitary renal mass: a case report.

BACKGROUND: Granulomatosis with polyangiitis (GPA) is characterized by necrotizing granulomatous vasculitis involving small-sized vessels in the upper airways, lower airways, and kidneys. Renal pathology is usually characterized by focal segmental necrotizing glomerulonephritis, which often leads to rapidly progressive renal failure. This type of renal involvement is usually unapparent on radiography. The presence of a renal mass in a patient with GPA, although extremely rare, is recognizable. Herein, we report a rare case of GPA presenting as a solitary renal mass and present a review of the literature. CASE PRESENTATION: A 75-year-old woman presented with a solitary right kidney mass measuring 4 × 3.5 cm detected by enhanced computed tomography. There was no history of sinusitis, rhinitis, cough, or pneumonia suggestive of systemic GPA. Nephrectomy was performed based on the suspicion of renal cell carcinoma or malignant lymphoma. Three months later, she was admitted because her serum creatinine levels increased from 54.81 µmol/L to 405.76 µmol/L accompanied by a high C-reactive protein level of 159 mg/L. Anti-neutrophil cytoplasmic antibodies against myeloperoxidase and anti-proteinase 3 were negative. Histological examinations of the solitary renal mass revealed necrotizing granulomatous arteritis in the cortex and medullary vasa recta, surrounded by interstitial fibrosis, and focal segmental necrotizing glomerulonephritis in the localized lesion; however, signs of vasculitis were not observed in areas other than the solitary mass. Therefore, the patient was diagnosed with granulomatosis with polyangiitis (GPA). Despite treatment with prednisolone (30 mg/day), the patient developed oliguria with an elevation of her serum creatinine level to 583.44 µmol/L, which required hemodialysis within one month after the initiation of steroid therapy. The patient could successfully discontinue hemodialysis 21 months later, following a decrease in her serum creatinine level to 251.06 µmol/L. CONCLUSIONS: GPA should be considered as one of the differential diagnoses of a solitary renal mass. Furthermore, patients with solitary renal masses associated with GPA may exhibit a favorable response to steroid or immunosuppressive treatment.

Paravertebral fibrous pseudotumor: Four cases of a distinctive tumefactive lesion overlapping with eosinophilic angiocentric fibrosis and tumoral erythema elevatum diutinum.

Eosinophilic angiocentric fibrosis (EAF) is a rare tumefactive fibroinflammatory disease with predilection for the upper respiratory tract, characterized by concentric (onionskin) fibrosis around small arterioles with variable intervening storiform fibrosis admixed with chronic inflammatory infiltrates rich in eosinophils. Erythema elevatum diutinum (EED), another autoimmunological disorder that mainly affects acral sites and extensor surfaces, is characterized by neutrophilic leukocytoclastic vasculitis. Rarely, older EED lesions may present as tumefactive nodular (pseudotumoral) fibrous masses closely mimicking EAF. We herein describe four patients (all males) aged 66-70 years who presented with large (median, 7 cm) tumor-like fibrous lesions in the paravertebral region not associated with a known clinical autoimmune disease. All cases were resected surgically with the suspicion of a neoplasm. They displayed a strikingly similar histological appearance with combined features of EAF and nodular fibrous EED. None had evidence of obliterative phlebitis or increased IgG4: IgG ratio. The etiology of this distinctive lesion and its predilection for the paravertebral area of males remains obscure. A distinctive tumefactive localized reaction to trauma caused by degenerative disease of adjacent vertebrae might be a possible explanation.

IgG4-negative pituitary inflammatory pseudotumor with sphenoidal involvement resembling a macroadenoma.

BACKGROUND: Inflammatory pseudotumors (IPTs) are rare benign conditions of unknown etiology that can affect any part of the body. IPTs are most commonly associated with Immunoglobulin G4 (IgG4)-related disease. Central nervous system IPTs, especially with pituitary involvement, are even rarer entities. The presence of an IgG4-negative pituitary IPT with simultaneous extracranial involvement has not been reported. CASE REPORT: We present the case of a 41-year-old female with past medical history of rheumatoid arthritis and a diagnosis of pituitary IPT with coexisting sphenoidal (extracranial) involvement mimicking a pituitary macroadenoma at presentation. The patient underwent multiple consecutive biopsies, and an extensive workup prior to establishing the diagnosis. Laboratory work-up showed normal serum IgG4 and unremarkable liver function tests. CONCLUSION: Pituitary lesions with simultaneous sphenoidal involvement in patients with IgG4-negative systemic inflammatory disease should raise the clinical suspicion for intracranial IPTs, as these tumors can mimic aggressive counterparts causing adjacent bony erosion, and local invasion.

Inflammatory Pseudotumour Of The Urachus: Case Report And Literature Review.

A 52 year old woman presented to the emergency department of Affiliated Hospital of Zunyi Medical University, Zunyi, China in May 2022, complaining of a palpable lower abdominal mass since two days. She denied haematuria, umbilical drainage, or any other urinary symptoms. Previous health record indicated that the patient was diagnosed with urachal inflammatory pseudotumour. Inflammatory pseudotumourous masses of the urachal canal are rare chronic inflammatory disorders with only a few case reports. Ultrasonography is the preferred method for diagnosing urachal lesions. Contrast- enhanced ultrasonography (CEUS) allows real-time visualization of the microvascular blood flow within the solid lesion, reducing the probability of misdiagnosis of the disease. We have reported a case of urachal inflammatory pseudotumour and analyzed its ultrasonographic findings from two-dimensional conventional ultrasonography and CEUS to provide support for the diagnosis of urachal inflammatory pseudotumour in the clinic and to assist clinical selection of effective treatment modalities.

Rare presentation of inflammatory myofibroblastic tumor on a digit.

Inflammatory myofibroblastic tumors (IMTs) are rare soft tissue neoplasms consisting of a mixture of spindle-shaped myofibroblasts or fibroblasts and a variable inflammatory infiltrate composed of eosinophils, plasma cells, and lymphocytes. Associations with trauma and infectious agents have been proposed, but the etiology is unknown. While IMT predominantly develops in the lungs of pediatric patients or young adults, extrapulmonary IMT is well documented and may occur anywhere. Cutaneous IMT is rare and few have been reported on the hand in the English language. The mean age of onset is 10 years, with a slight female predilection. IMT demonstrates intermediate malignant potential, with a tendency to recur locally. Metastases are rare. According to a recent review, anaplastic lymphoma kinase (ALK) positivity on immunohistochemistry is related to local recurrence, but not distant metastases. We report an unusual case of a 36-year-old male, with a lesion on the right second digit, displaying classic histopathologic and immunohistochemical features of IMT, including ALK staining, and confirmatory fluorescence in situ hybridization-proven ALK gene rearrangement.

Imaging features and radiologic-pathologic correlations of inflammatory pseudotumor-like follicular dendritic cell sarcoma.

BACKGROUND: Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a rare tumor. This study aimed to reveal the radiological characteristics of IPT-like FDCS by radiologic-pathologic correlation. RESULTS: We analyzed two cases of IPT-like FDCS in the liver, nine in the spleen, and two in both the liver and spleen concomitantly. IPT-like FDCS presented as well-defined iso- or hypodense masses on unenhanced computed tomography (CT) images in both the liver and spleen. Hyperintensities on T1-weighted images and hypointensities on T2-weighted images with hypointense rings were characteristic features in splenic cases. "Halo signs" were observed in two out of three liver tumors. Hepatic lesions showed significant enhancement, whereas splenic lesions showed only mild enhancement. Delayed annular enhancement was observed in both liver and spleen cases. On ultrasonographic examination, IPT-like FDCS presented as hypoechoic lesions with enhancement similar to that observed on CT. Hyaline fibrous pseudocapsules, which correlated with the hypointensities on T2-weighted images, were microscopically observed at the tumor edge. IPT-like FDCS was characterized by an abundance of small blood vessels and capillaries. Capillaries were also found in the fibrous capsule of some IPT-like FDCSs, which may explain the delayed annular enhancement. CONCLUSIONS: The manifestations of IPT-like FDCS in the liver and spleen showed differences that warrant them to be approached differently during diagnosis. Characteristic radiological findings of IPT-like FDCS included different enhancement patterns between liver and spleen tumors and rim-like hypointensities on T2-weighted images, as well as annular enhancement on CT and magnetic resonance images. These imaging features correlated with tumor pathology.

A rare case of inflammatory pseudotumor located in the ventral of medullocervical junction. A case report and review of literature.

Inflammatory pseudotumor is a benign lesion of unknown etiology, which mimics neoplasms clinically and radiographically. It most commonly involves the lungs and orbits and is rarely reported in the central nervous system. We report a rare case of inflammatory pseudotumor located in the ventral junction of the medulla oblangta and cervical cistern, which has not been reported before as far as we know. A 61-year-old male presented with right arm weakness. MRI showed a mass located in the ventral junction of the medulla oblongata and cervical cisten. The patient was diagnosed as inflammatory pseudotumor(IPT) after surgical excision and histopathology. This tumor-like lesion was surrounding the bilateral intracranial segment of the vertebral arteries. No evidence of vascular invasion was observed. Complete surgical resection was achieved.

Imaging of IgG4-Related Disease in the Head and Neck: A Systematic Review, Case Series, and Pathophysiology Update.

This systematic review aims to clarify and comprehensively detail the sometimes variable published imaging features as well as the pathogenesis, clinical diagnostic criteria, and treatment options of IgG4-Related Diseases (IgG4-RD) in the head and neck to aid the radiologist in diagnosing relapse and new sites of disease. A literature search in PubMed and EMBASE for reported cases of IgG4-RD was performed in December 2019. Case reports or series of IgG4-RD in the head and neck in adults that included sufficient imaging and pathology findings were included. This yielded 50 reports. IgG4-RD locations included the orbits, thyroid, pituitary gland, paranasal sinuses, salivary and parotid glands, larynx, pharynx, cervical lymph nodes, meninges, and skull base. Most lesions demonstrated non-specific homogenous CT attenuation, diffuse enhancement, isointense/low T2 signal intensity, and low T1 signal intensity. 6 cases from our institution followed previously reported imaging patterns.

A case of inflammatory pseudotumour of the gallbladder presenting as a big mass of uncertain behavior.

BACKGROUND: Inflammatory pseudotumour has been used to describe an inflammatory or fibrosing tumoral process of an undetermined cause that may involve a variety of organ systems, including the lungs, spleen, liver, lymph nodes, pancreas and extrahepatic bile duct with potential for recurrence and persistent local growth. In this article, we report a patient with a big mass of uncertain nature and behavior. CASE PRESENTATION: A 60-year-old woman presented with a 1-week history of abdominal pain, fever and jaundice. Six months before she had had right upper quadrant pain that was interpreted as biliary colic. A contrast-enhanced CT scan showed a big mass of soft tissue with diffuse infiltration of the gallbladder, displacement of the transverse colon, hepatic flexure and duodenum. For diagnostic distinction between a chronic inflammatory disease or a neoplasm, exploratory laparotomy was required. Intraoperative exploration disclosed a big mass of hard texture involving the gallbladder, with multiple concrements, hepatoduodenal ligament, right and transverse mesocolon, stomach and duodenum. Cholecystectomy was performed, preserving adjacent organs with macroscopic desmoplastic reaction. Histopathologic examination of the gallbladder showed a spindle cell proliferation with diffuse chronic inflammatory infiltrate of lymphocytes, plasma cells and hyalinized fibrous stroma. No vascular invasion or cellular atypia were evident. CONCLUSION: Inflammatory pseudotumour is a rare condition and diagnostic distinction from a chronic inflammatory disease or other neoplasm is only possible by histopathologic examination. There is a limited number of case reports in the literature indicating tumor location in the gallbladder.

Inflammatory pseudotumor associated with HSV infection of rectal vascular endothelium in a patient with HIV: a case report and literature review.

BACKGROUND: Herpes simplex virus (HSV) typically infects oral or anogenital squamous epithelium and causes blisters and ulcerations. Here we reported an unusual case of HSV induced exuberant rectal inflammatory pseudotumor with vascular endothelial involvement. CASE PRESENTATIONS: A 52-year old man with HIV presented with abdominal pain, rectal drainage and constipation. Proctoscopy and CT scans revealed an 8 × 5 × 4 cm circumferential, mid-lower rectal mass that was concerning for malignancy. PET-CT showed mild to moderate FDG uptake of the rectal mass. Repeated biopsies showed exuberant lymphoplasmacytic inflammation with rich eosinophils and necrosis in the submucosa and scattered single or multi-nucleated viral inclusions in vascular endothelial cells that were positive for HSV by immunostains. There was no evidence of malignancy on histology or by immunostains. The patient started valacyclovir for three weeks and symptoms resolved after the antiviral therapy. Follow-up CT and sigmoidoscopy with biopsy revealed no rectal mass or drainable collection. CONCLUSIONS: HSV may present as proctitis with exuberant inflammatory response and mass-like lesion, and damages vascular endothelial cells in patients with HIV. The HSV-associated mass-like lesion can be effectively treated by 3-week valacyclovir.

Using CT texture analysis to differentiate between peripheral lung cancer and pulmonary inflammatory pseudotumor.

BACKGROUND: This study is to distinguish peripheral lung cancer and pulmonary inflammatory pseudotumor using CT-radiomics features extracted from PET/CT images. METHODS: In this study, the standard 18F-fluorodeoxyglucose positron emission tomography/ computed tomography (18 F-FDG PET/CT) images of 21 patients with pulmonary inflammatory pseudotumor (PIPT) and 21 patients with peripheral lung cancer were retrospectively collected. The dataset was used to extract CT-radiomics features from regions of interest (ROI), The intra-class correlation coefficient (ICC) was used to screen the robust feature from all the radiomic features. Using, then, statistical methods to screen CT-radiomics features, which could distinguish peripheral lung cancer and PIPT. And the ability of radiomics features distinguished peripheral lung cancer and PIPT was estimated by receiver operating characteristic (ROC) curve and compared by the Delong test. RESULTS: A total of 435 radiomics features were extracted, of which 361 features showed relatively good repeatability (ICC ≥ 0.6). 20 features showed the ability to distinguish peripheral lung cancer from PIPT. these features were seen in 14 of 330 Gray-Level Co-occurrence Matrix features, 1 of 49 Intensity Histogram features, 5 of 18 Shape features. The area under the curves (AUC) of these features were 0.731 ± 0.075, 0.717, 0.748 ± 0.038, respectively. The P values of statistical differences among ROC were 0.0499 (F9, F20), 0.0472 (F10, F11) and 0.0145 (F11, Mean4). The discrimination ability of forming new features (Parent Features) after averaging the features extracted at different angles and distances was moderate compared to the previous features (Child features). CONCLUSION: Radiomics features extracted from non-contrast CT based on PET/CT images can help distinguish peripheral lung cancer and PIPT.

Paraneoplastic disorders associated with miscellaneous neoplasms with focus on selected soft tissue and Undifferentiated/ rhabdoid malignancies.

A variety of soft tissue and visceral neoplasms have been associated with constitutional symptoms and signs including fever, fatigue, arthritis and laboratory abnormalities such as elevated erythrocyte sedimentation rate, leukocytosis with marked neutrophilia, anemia, thrombocytosis and others. This review addresses three main neoplastic categories that are associated with specific paraneoplastic phenomena: (1) neoplasms having in common the presence of diffuse mixed inflammatory infiltration (closely simulating an inflammatory pseudotumor) and frequently associated with constitutional symptoms; (2) neoplasms with undifferentiated, anaplastic or rhabdoid cell morphology (frequently SWI/SNF-deficient) associated with diverse paraneoplastic manifestations; and (3) paraneoplasia associated with neoplasms carrying specific gene fusions such as solitary fibrous tumor (STAT6-NAB2 gene fusions), infantile fibrosarcoma and congenital mesoblastic nephroma (ETV6-NTRK3 gene fusions), and angiomatoid fibrous histiocytoma (EWSR1-CREB1 & EWSR1-ATF1 fusions).

Immunoglobulin G4-related hepatobiliary disease.

Immunoglobuline G4-related disease (IgG4-RD) is a systemic disease that can involve virtually any organs including the biliary tract and liver. The biliary tract involvement of IgG4-RD is known as IgG4-sclerosing cholangitis (IgG4-SC) and may or may not present with an inflammatory pseudotumor. Large bile ducts such as extrahepatic, hilar, and perihilar ducts are typically affected and demonstrate marked bile duct wall thickening and develop strictures. Histologically, the involved ducts show transmural dense lymphoplasmacytic infiltrates with storiform fibrosis extending into peribiliary glands and periductal soft tissue. The luminal epithelium is usually preserved. Tissue eosinophilia and obliterative phlebitis are also frequently noted. Liver biopsy findings of IgG4-SC are heterogeneous and rather nonspecific, but two features specific to IgG4-SC have been described: >10 IgG4-positive plasma cell/HPF and small portal-based fibroinflammatory nodules. Secondary changes, due to downstream bile duct obstruction are often appreciated. When considering the differential diagnosis, primary sclerosing cholangitis and cholangiocarcinoma are great clinical and histologic mimics of IgG4-SC. Liver involvement in IgG4-RD has not been well characterized and includes IgG4-hepatopathy and IgG4-related autoimmune hepatitis (AIH). IgG4-hepatopathy is a generic term covering hepatic lesions related to IgG4-RD and /or IgG4-SC. It includes primary liver parenchymal changes inherent to IgG4-RD, liver parenchymal involvement of IgG4-SC, and secondary changes related to IgG4-SC. IgG4-related AIH is characterized by clinical and histologic features of classical AIH but with prominent (>10/HPF) IgG4-positive plasma cells. It is unclear whether this represents a hepatic manifestation of IgG4-RD or a subset of AIH with increased IgG4-positive plasma cells at the present time. Synchronous or metachronous involvement of other organs, offers a clue to make this distinction. IgG4 immunohistochemistry has an important role in diagnosing IgG4-RD. But the diagnosis cannot be made solely based on the number of IgG4-positive plasma cells, and results need to be interpreted with caution as increased IgG4-positive plasma cells can be seen in other inflammatory conditions or even in malignancy.

Clinical significance of IgG4 in sinonasal and skull base inflammatory pseudotumor.

INTRODUCTION: Inflammatory pseudotumor (IPT) in the sinonasal cavity and skull base region is benign non-neoplastic inflammatory process. However, IPT can mimic malignant tumor or infectious disease and there are difficulties in confirmation of diagnosis. The aim of study is to evaluate the clinical significance of immunoglobulin G4 (IgG4) in IPT in terms of steroid response and differential diagnosis with other skull base infiltrative lesions. METHODS: Medical records were reviewed retrospectively from 1998 to 2016. Subjects diagnosed with IPT by surgical biopsy were enrolled. IgG4 positivity was defined as IgG4/IgG ratio > 0.4. Additionally, IgG4/IgG ratio was calculated in eight skull base osteomyelitis (SBO) patients. RESULTS: Twenty-six IPT patients were included and the average age was 52.3 years, and 57.7% were male and 42.3% were female. Most lesions were involved in the sinuses (88.5%) and the incidence of extension beyond the sinuses itself was as follows: the cheek/hard palate/parapharynx (15.4%), orbit (61.5%), skull base (57.7%), and dura or brain (23.1%). All IPT cases revealed IgG4 + plasma cells and IgG4/IgG ratio over 0.4 was detected in 42.3% (11/26) of cases. In case of SBO, no patients had IgG4/IgG ratio exceed 0.4. Main treatment modality was systemic steroids (61.5%) and other modalities were used: surgery (3.8%), immunosuppressant (7.7%), radiotherapy (30.8%), or a combination of these modalities (15.4%). Steroid responses were not significantly different, but IgG4-positive group tended to have better response to steroid therapy. CONCLUSIONS: IgG4-positive and IgG4-negative IPT patients revealed no differences in involvement sites, clinical course, and steroid responses. However, IgG4/IgG ratio and IgG4 + plasma cell count can provide a diagnostic clue for infiltrative skull base lesions such as IPT and a differential diagnosis of SBO.

A Curious Case of Cough in a Young Woman

Inflammatory myofibroblastic tumour (IMT) is a rare neoplasm derived from tissue of mesenchymal origin. This tumour occurs predominantly in the lung, though extrapulmonary sites have been documented throughout the body.1 Presentation can be variable depending on location of the tumour and can include constitutional symptoms (fever, weight loss), thrombocytosis, hypergammaglobulinemia, anemia, and mass effect on local structures.2 Majority of patients with intrapulmonary IMT remain asymptomatic but can have symptoms including chest pain, dyspnoea, cough or haemoptysis.3 Most cases of IMT present in younger individuals (under age 40).4 Although the aetiology of IMT is unclear, current hypotheses suggest an inflammatory response to infection or an underlying malignancy could promote such cellular changes. Alternatively, the inflammatory component itself may be a consequence of the development of these mesenchymal tumours.

Differentiation of orbital lymphoma and idiopathic orbital inflammatory pseudotumor: combined diagnostic value of conventional MRI and histogram analysis of ADC maps.

BACKGROUND: The overlap of morphological feature and mean ADC value restricted clinical application of MRI in the differential diagnosis of orbital lymphoma and idiopathic orbital inflammatory pseudotumor (IOIP). In this paper, we aimed to retrospectively evaluate the combined diagnostic value of conventional magnetic resonance imaging (MRI) and whole-tumor histogram analysis of apparent diffusion coefficient (ADC) maps in the differentiation of the two lesions. METHODS: In total, 18 patients with orbital lymphoma and 22 patients with IOIP were included, who underwent both conventional MRI and diffusion weighted imaging before treatment. Conventional MRI features and histogram parameters derived from ADC maps, including mean ADC (ADCmean), median ADC (ADCmedian), skewness, kurtosis, 10th, 25th, 75th and 90th percentiles of ADC (ADC10, ADC25, ADC75, ADC90) were evaluated and compared between orbital lymphoma and IOIP. Multivariate logistic regression analysis was used to identify the most valuable variables for discriminating. Differential model was built upon the selected variables and receiver operating characteristic (ROC) analysis was also performed to determine the differential ability of the model. RESULTS: Multivariate logistic regression showed ADC10 (P = 0.023) and involvement of orbit preseptal space (P = 0.029) were the most promising indexes in the discrimination of orbital lymphoma and IOIP. The logistic model defined by ADC10 and involvement of orbit preseptal space was built, which achieved an AUC of 0.939, with sensitivity of 77.30% and specificity of 94.40%. CONCLUSIONS: Conventional MRI feature of involvement of orbit preseptal space and ADC histogram parameter of ADC10 are valuable in differential diagnosis of orbital lymphoma and IOIP.

Lymphadenopathy associated with IgG4-related disease: Diagnosis & differential diagnosis.

IgG4-related sclerosing disease, which now encompasses diverse organ-related disorders with various prior eponymic designations, may also present with solitary or multifocal lymph node enlargement. This review considers the histopathologic features of IgG4 lymphadenopathy (IgG4LAD), which has been subdivided by Cheuk & Chan into 5 microscopic subtypes. Those include variants that are typified by multicentric Castleman disease (MCD)-like changes, follicular hyperplasia, interfollicular lymphoplasmacytic proliferation, progressive transformation of germinal centers, and formation of inflammatory pseudotumor (IPT)-like lesions. All of them demonstrate an excess of IgG4-immunoreactive plasma cells in the inflammatory cell population. Differential diagnostic considerations for IgG4LAD include true MCD, true IPT, luetic lymphadenitis, Rosai-Dorfman disease, and inflammatory myofibroblastic tumor, among others. An interpretative distinction between malignant lymphoma and IgG4LAD is also crucial.

Calcifying fibrous pseudotumour of maxilla: A rare entity mimicking malignancy: A case report.

Occurrence of inflammatory pseudotumour in head and neck region or nose and paranasal sinuses is rare. However, when they do occur, they could be quite aggressive. Etiologically, they are believed to be reactive than neoplastic, and calcification may suggest end-stage. Their clinical presentation and radiologic features may resemble a malignancy. Grossly, they are not encapsulated, but multilobulated and can be circumscribed or infiltrative. Histologically, they constitute of bland spindle cells with scant cytoplasm and occasional mitotic figures. Scattered lymphocytic and plasma cell infiltrates with abundant dense hyalinized collagenous stroma and focal small calcifications are seen. Presence of atypia, DNA aneuploidy, and abnormal p53 expression may suggest malignant potential. Though not known to metastasize, they can lead to local complications, causing destruction of bone and surrounding tissues. Management is mainly by surgical excision though adjunct corticosteroids have been advocated. We report such a rare case of calcifying fibrous pseudotumour of maxilla.

Combined liver transplant and pancreaticoduodenectomy for inflammatory hilar myofibroblastic tumor: Case report and review of the literature.

IMT, previously known as IPT, is a relatively rare tumor that was originally described in the lungs, but case reports have reported the tumor in almost every organ system. Surgical resection is typically the mainstay of therapy; however, tumors have also been shown to respond to chemotherapy or anti-inflammatory therapy and some have spontaneously regressed. We present a literature review and case report representing the first documentation to date of liver transplant combined with PD for surgical resection of a myofibroblastic tumor non-responsive to medical therapy.