Number Of IgG4-positive Plasma Cells Research Articles

IgG4-Related Disease, a Systemic or Local Disease: This is the Problem

Background: Immunoglobulin G4-related disease (IgG4-RD) is a fibroinflammatory condition that forms tumefactive lesions in various organs, presenting with diverse clinical manifestations. Diagnosis of IgG4-RD could be challenging and relies on characteristic histopathological findings and elevated IgG4+ plasma cell counts. Case Presentation: The patient was a 48-year-old woman with diabetes mellitus initially presented with a painless breast mass. Imaging indicated irregular opacities and lymph nodes in the breast. Biopsy results revealed lymphoplasmacytic infiltration with IgG and IgG4 positivity, overall compatible with IG4-related disease. A mass resection was performed, and intraoperative assessment ruled out malignancy. Then, with a 5-month interval of no symptoms, the patient developed a cheek mass, initially misdiagnosed as low-grade spindle cell sarcoma. Subsequently, she underwent partial maxillectomy and further examination and histology confirmed IgG4-RD, meeting all diagnostic criteria. Conclusion: IgG4-RD is a rare, systemic fibroinflammatory condition with potential to mimic neoplastic processes. While IgG4 serum levels can be elevated, they are not a reliable diagnostic criterion. The two main features of IgG-related disease are an elevated number of IgG4-positive plasma cells within the tissue and a characteristic histopathological appearance including a dense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis. Overall, diagnosis is based on the balance of clinical features, histopathology, and serum markers. This case underscores the diagnostic challenges posed by IgG4-RD, often mistaken for malignancies due to its invasive behavior and emphasizes the importance of considering IgG4-RD in differential diagnoses for tumor-like lesions, particularly when affecting multiple organs, to enable timely treatment decisions and prevent unnecessary interventions.

Successful surgical management of an aggressive IgG4-related sclerosing esophageal inflammatory pseudotumor: a case report and review of literature

BackgroundInflammatory pseudotumor (IPT) of the esophagus is a very rare benign lesions which clinical presentation is not clear and difficult to make a definitive diagnosis preoperatively.Case presentationIn this report, we presented a case of a 24-year-old female with signs of severe malnutrition state due to dysphagia increasing gradually and losing 10 kg in weight for 2 months. Comprehensive preoperative radiologic investigations were proceeded with a circumferential severe stricture caused smooth submucosal swelling in the esophagus under 23 cm from the upper dental arch and two times of negative biopsy. Due to the aggressive clinical symptoms and gross lesion characteristics, the patient underwent laparoscopic-thoracoscopic esophagectomy and reconstruction with a gastric tube. Histopathological examination showed that the squamous epithelium of the esophagus had a small, benign nucleus, the submucosal layer and the smooth muscle layer increased fibrous, with infiltrating many lymphocytes, plasma cells, and macrophages. Immunohistochemical staining was negative for CD68, CD34, Desmin and ALK markers, and there was an increase in the number of IgG4-positive plasma cells. The final diagnosis was an aggressive IgG4-related sclerosing esophageal inflammatory pseudotumor.ConclusionsInflammatory pseudotumor of the esophagus is an extremely rare benign lesion but could led to aggressive clinical presentation. The gold standard of diagnosis is histopathological examination of surgically removed specimens. Radical resection is still the most efficient treatment method.

IgG4 expression and IgG4/IgG ratio in the tumour invasion front predict long-term outcomes for patients with intrahepatic cholangiocarcinoma

IgG4-positive plasma cells are reportedly increased in the tumour microenvironment, and a high number of these cells in tumours is a poor prognostic factor in several cancers. However, there are no reported analyses of IgG4 expression in intrahepatic cholangiocarcinoma (ICC). This study aimed to analyse the correlations between prognosis-related clinicopathological features of patients with ICC and IgG4 expression. We identified 37 ICC patients who underwent surgical resection between January 2010 and December 2020. The number of IgG-positive and IgG4-positive plasma cells in the tumour, invasion front, and stroma near the tumour was analysed by immunostaining. Furthermore, we examined the association of prognosis-related clinicopathological data with the number of IgG4-positive plasma cells and IgG4/IgG ratio in ICC patients. The IgG4-positive plasma cell percentages for the intra-tumour area, invasion front, and non-cancerous area (NCA) near the tumour were 91.9%, 56.8%, and 81.1%, respectively. IgG-positive plasma cells were observed in each region for all cases, except for NCA tissue in one case. A high IgG4 expression level and IgG4/IgG ratio in the invasion front were significantly associated with poor overall survival (OS) (log-rank test p=0.0438 and p=0.0338, respectively). Multivariate analysis for OS revealed that high IgG4 expression (p=0.0140), lymph node metastasis (p=0.0205), and positive surgical margin (p=0.0009) or a high IgG4/IgG ratio (p=0.0051), lymph node metastasis (p=0.0280), and positive surgical margin (p=0.0009) were independent poor prognostic factors. In conclusion, a high IgG4 expression level and IgG4/IgG ratio in the invasion front are independent poor prognostic factors for ICC. Targeted therapy for IgG4 may improve the prognosis for patients with ICC.

P33 A female with a drooping eyelid and positive autoantibodies: mystery solved?

Case report - IntroductionThe presence of autoantibodies in IgG4-related disease (IgG4-RD) can lead to confusion and we present a case to highlight the diagnostic difficulty in this condition.Case report - Case descriptionA 63-year-old Indian female presented with progressive ptosis and swelling of the left eyelid for 2 months. She was referred to the stroke clinic where she was found to have left ptosis with associated swelling. An MRI of the orbit revealed an enlarged left lacrimal gland and mucosal thickening in paranasal sinuses. Her ESR was 20, CRP 2, 15% peripheral eosinophils and IgG 17.55 g/L (6-16). A referral was made to rheumatology due to an abnormal immunological profile: cANCA +, MPO ANCA positive 32 IU/ml (0-3.5) and a strongly positive anti-Ro antibody >600 U/ml (0-10). Differential diagnosis considered: ANCA associated vasculitis (AAV), Primary Sjögren’s syndrome (SS), and IgG4-related orbital disease. She was assessed by the ENT surgeon and there was no sinusitis or evidence of vasculitis. Chest X-ray and CT scan of chest were normal.A left lacrimal gland biopsy revealed reactive lymphoid hyperplasia with numerous plasma cells and eosinophils. Immunohistochemistry revealed over 50% of plasma cells to be IgG4-positive (approximately 100/HPF) suggestive of IgG4-RD. There was no evidence of granuloma formation or malignancy. Serum IgG4 was raised 6.82 g/l (<1.3). A review by ophthalmology revealed no objective evidence of dry eyes. She was treated as IgG4-RD and demonstrated a marked improvement following treatment with oral steroids and azathioprine.Case report - DiscussionIgG4-RD is an immune-mediated systemic fibro inflammatory disease characterised by tumefactive lesions with abundant IgG4-positive plasma cells infiltrating into multiple organs. Isolated IgG4-related ophthalmic disease is present in 23% of patients with IgG4-RD, in whom the lacrimal gland is the most commonly involved structure, followed by orbital fat and extraocular muscles. IgG4-related ophthalmic disease is rare and we need to exclude commoner causes of orbital inflammation (such as thyroid ophthalmopathy, granulomatosis with poly-angiitis, sarcoidosis, and tuberculosis) or malignancy.Case report - Key learning pointsThe diagnosis of IgG4-RD is often challenging. It is well recognised that small vessel vasculitis can increase the number of IgG4-positive plasma cells in tissue biopsies. Additionally, literature reveals biopsy-proven IgG4-RD can have ANCA positivity with and without concomitant presence of ANCA-associated vasculitis and there are case reports of patients who fulfil criteria for both Sjogren’s syndrome and IgG4-RD. As such, diagnosis requires careful correlation of clinical, radiologic and histological features due to the overlapping features in differential diagnoses.

Pleuritis associated with immunoglobulin G4-related disease under normal thoracoscopic findings: a case report

BackgroundImmunoglobulin G4 (IgG4)-related disease is a chronic inflammatory disease that was recognized in 2011. Pleuritis associated with IgG4-related disease is rare and can be difficult to diagnose. Although there have been previous reports on pleuritis associated with IgG4-related disease by thoracoscopic findings, this is the first to observe pleuritis with IgG4-related disease from normal pleural thoracoscopic findings.Case presentationA 70-year-old Japanese female treated for breast cancer 33 years ago was referred to our hospital complaining of dyspnea on exertion. Chest computed tomography (CT) revealed left pleural effusion that was exudative and predominant with lymphocytes, elevated adenosine deaminase (ADA) and Class III cytology (malignancy suspected). Subsequently, thoracoscopic pleural biopsy was performed for definitive diagnosis. Although pleural macroscopic findings appeared normal, we performed pleural biopsy at random sites. This patient was negative for mycobacterium tuberculosis, and neither granulomas nor malignant cells were found in the collected specimens. An infiltration of inflammatory cells, mainly plasma cells and lymphocytes, was observed. Immunostaining revealed the number of IgG4-positive plasma cells was 102/high power field (HPF), and the percentage of IgG4 positive/immunoglobulin G (IgG)-positive cells was 41.4%. Since IgG4 serum levels were high and IgG4-related submandibular sialadenitis was also observed, a definitive diagnose of pleuritis associated with IgG4-related disease was confirmed.ConclusionsWe diagnosed pleuritis associated with IgG4-related disease by thoracoscopic pleural biopsy samples taken from a visually normal pleura. Although exudative pleural effusion with high ADA and lymphocyte predominance is a characteristic of tuberculous pleuritis, other diseases might be present. Since thoracoscopy can increase the diagnostic yield, pleural biopsy should be considered even if thoracoscopic pleural findings are deemed normal.

IgG4-related gastric disease with plasma cell-rich obliterative arteritis accompanied by early-stage gastric cancer: a case report

BackgroundImmunoglobulin G4-related disease (IgG4-RD) is an immune-mediated inflammatory disorder that can involve multiple organs. It is characterized by IgG4-positive plasma cell-rich storiform fibrosis and obliterative phlebitis associated with a high serum IgG4 level. There are few reports of gastric IgG4-RD, especially those detected prior to systemic or other organ involvement.Case presentation: A 70-year-old man was diagnosed with type 0–IIc gastric cancer at the anterior wall of the gastric corpus by upper gastrointestinal endoscopy. In addition, a submucosal tumor (SMT) 7 mm in diameter was found at the greater curvature of the angulus. Laparoscopic distal gastrectomy with regional lymph node dissection was performed. Pathology revealed a poorly differentiated adenocarcinoma in the type 0–IIc lesion and storiform fibrosis with infiltration of a large number of IgG4-positive plasma cells in the SMT. Postoperative laboratory testing showed elevation of serum IgG4 levels; thus, we diagnosed the SMT as IgG4-RD. Intriguingly, the gastric IgG4-RD lesion demonstrated IgG4-positive plasma cell-rich arteritis as well as typical obstructive phlebitis. The patient has been followed for 2 years after surgery without recurrence of cancer, but skin lesions of IgG4-RD have appeared.ConclusionWe report a rare case of IgG4-RD presenting as a gastric SMT, accompanied by early-stage gastric cancer. Our case may support a newly proposed relationship between IgG4-RD and malignancies. The gastric IgG4-RD lesion showed arteritis as well as obliterative phlebitis, potentially providing novel insight into IgG4-related vascular lesions.

Clinicopathological Features of Follicular Dendritic Cell Sarcoma

Objective To explore the clinicopathological and immunohistochemical characteristics of follicular dendritic cell sarcoma(FDCS)and the expressions of IgG and IgG4. Methods We retrospectively analyzed the clinicopathological and immunohistochemical data of 9 pathologically confirmed FDCS cases in Peking Union Medical College Hospital from January 2005 to December 2018.Immunohistochemical staining of IgG and IgG4 were performed,and Epstein-Barr virus(EBV)-encoded RNA(EBER)in situ hybridization were carried out. Results Nine cases of FDCS included 4 men and 5 women aged 16-53 years [mean(38.2±9.7)years].The clinical manifestations included masses,lymph node enlargement,rash,and fever.The tumors were located in lymph node,retroperitoneal region,adrenal gland,neck,axillary region,and liver,respectively.Ultrasound showed clear boundary cystic or solid mass with maximum diameters of 1.5-15.0 cm.Microscopically,the spindle tumor cells were arranged in solid and storiform patterns with abundant and slightly stained cytoplasm,vacuolated nuclei,and small nucleoli.The mitosis was 1-3/10 high power fields,and necrosis was found in 5 cases.Immunohistochemically,the tumor cells were positive for CD21(6/9),CD35(6/9),and CD23(7/9). Conclusions FDCS is a rare malignant tumor,which is easy to be missed.The combination of CD21,CD35,and CD23 is helpful for diagnosis.Hyaline-vascular type Castleman's disease may be the precursor of FDCS,and there may be only a small number of IgG4-positive plasma cells in FDCS.Surgical resection remains the main treatment for FDCS.

Calcifying fibrous tumour: An IgG4-related disease or not?

Calcifying fibrous tumour (CFT) has some of the histopathological features, such as abundant plasma cells and stromal fibrosis, that are exhibited by IgG4-related diseases (IgG4-RD). The possible role of IgG4-positive plasma cells in calcifying fibrous tumour was investigated. The aim of this study was to determine any potential relationship between IgG4-RD and CFT. Thirteen cases with a total of 16 CFTs were reviewed. Lesion samples were immunostained with anti-IgG4 and anti-IgG antibodies. The number of IgG4-positive and IgG-positive plasma cells (IgG+PC) and their ratios were estimated. Plasma cells were found in all tumours. IgG4-positive plasma cells ranged from 0 to 71 per high-power field (HPF; mean 17.8/HPF), and IgG+PC ranged from 2 to 93/HPF (mean 42.6/HPF). The IgG4/IgG ratio ranged from 0% to 80% (mean 29%). There were seven tumours with the ratio of IgG4/IgG+PC that exceeded 40%. Various degrees of stromal fibrosis were present in eight tumours. All tumours have variable calcification. The histopathological features of CFT were found to be similar to those of IgG4-RD. Some CFT also showed a high number of IgG4-positive plasma cells, and the ratio of IgG4/IgG+PC exceeded 40%, most notably in patients with concomitant inflammatory or autoimmune disease. The long-term follow-up showed no evidence of IgG4-RD in any of these patients. Our findings suggest that while CFT overlaps morphologically with IgG4-RD, it probably should not be classified as an IgG4-RD.

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.

The histological diagnosis of IgG4‐related disease on small biopsies: challenges and pitfalls

The pathological diagnosis of IgG4-related disease (IgG4-RD) relies on histology, IgG4-positive cells, and an increased IgG4/IgG ratio. Small biopsies from patients with a presumptive diagnosis of IgG4-RD often fail to meet consensus histological criteria. The aims of this study were to evaluate consecutive small biopsies from patients with a presumptive diagnosis of IgG4-RD, and to assess the significance of the pathological findings. We evaluated 55 small biopsies from patients with a presumptive diagnosis of IgG4-RD. The retrospective cohort comprised 71 patients with IgG4-RD and 57 mimics. We performed immunohistochemistry (IHC) and in-situ hybridisation (ISH) for IgG4 and IgG. Twenty-six patients from the prospective cohort met the histological criteria for IgG4-RD (definite); 29 patients lacked one or more pathological features (borderline). Twenty biopsies (36%) lacked both storiform fibrosis and obliterative phlebitis, and nine (16%) lacked an increase in the number of IgG4-positive plasma cells. Ninety-three per cent of patients showed an IgG4/total IgG ratio of >40% (>30% by ISH). There were no differences in the incidence of multiorgan disease (P=0.9), serum IgG4 levels (P=0.6) and response to therapy between the definite and borderline groups. A strong correlation (Pearson 0.77) between the IHC and ISH platforms was noted with regard to the IgG4/total IgG ratio. Patients with a presumptive diagnosis of IgG4-RD but lacking the characteristic pathological features of this disease appear to be clinically similar to those who meet the current pathological criteria. An elevated IgG4/total IgG ratio is the most sensitive pathological feature, and ISH provides a robust quantification platform. We recommend evaluating tumefactive lymphoplasmacytic infiltrates with an increased IgG4/IgG ratio, regardless of histological features, for IgG4-RD.

A high number of IgG4-positive plasma cells rules out nodular lymphocyte predominant Hodgkin lymphoma.

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a subtype of Hodgkin lymphoma that frequently shows a nodal growth pattern with abundant reactive B cells in the microenvironment. Early NLPHL cases can be particularly difficult to differentiate from progressively transformed germinal centers (PTGC). Since PTGC have been described to be IgG4 associated in a relatively high proportion of cases, the aim of the present study was to determine if IgG4 immunostaining can be helpful in the differential diagnosis between NLPHL and PTGC. We furthermore aimed to learn if LP cells can express IgG4. For this purpose, 58 cases of PTGC and 56 cases of NLPHL were assessed using IgG4 immunostaining. We could confirm that a significant number of PTGC cases showed high numbers of IgG4-positive plasma cells (22/58, 38%), whereas hot spot areas of IgG4-positive plasma cells were not found in any of the NLPHL cases. In lymph node areas with the differential diagnosis of NLPHL and PTGC, IgG4 immunostaining can therefore provide a helpful diagnostic tool to rule out NLPHL when a high number of IgG4-positive plasma cells are encountered. We also assessed 13 cases with a combination of NLPHL and PTGC in the same lymph node. Five of these cases presented hot spot areas of IgG4-positive plasma cells in the PTGC regions, while no significant numbers of IgG4-positive plasma cells were observed in the NLPHL part of the lymph node. LP cells were never IgG4 positive. Furthermore, immunoglobulin heavy chain rearrangements of single IgG4-positive plasma cells were analyzed, revealing a polyclonal plasma cell population. In summary, our data suggest that IgG4 immunostaining can provide additional information in the diagnostic workup of cases with the differential diagnosis of NLPHL and PTGC. IgG4's inefficiency in clearing antigens may explain why lymph nodes with PTGC are usually strongly enlarged and develop a high number of hyperplastic germinal centers. Polyclonal immunoglobulin heavy chain rearrangements in IgG4-positive plasma cells further support the hypothesis that PTGC represent a misled immune reaction.

Immunoglobulin G4–related chronic rhinosinusitis: a pitfall in the differential diagnosis of granulomatosis with polyangiitis, Rosai-Dorfman disease, and fungal rhinosinusitis

Immunoglobulin G4 (IgG4)-related chronic rhinosinusitis (CRS) has recently been proposed to be a new clinical entity of nasal disease, with no consensually agreed criteria for diagnosis. Moreover, the pathological features of IgG4-related CRS often overlap with other sinonasal inflammatory and autoimmune diseases such as granulomatosis with polyangiitis (GPA), Rosai-Dorfman disease (RDD) and fungal rhinosinusitis (FRS). We aimed to explore the specific similarities and differences in clinicopathologic features between IgG4-related CRS, and GPA, RDD and FRS, in order that these conditions can be diagnosed more accurately. Biopsy specimens collected from nasal mucosa of 20 IgG4-related CRS, 10 GPA, 10 RDD and 10 FRS patients were assessed by hematoxylin and eosin staining and immunohistochemical techniques for specific histochemical differences. The number of IgG4-positive plasma cells /high-power fields (HPF) in biopsies from IgG4-related CRS patients (mean=79.6±51.59; range=15/HPF to 230/HPF) was significantly higher than in biopsies from GPA (mean=13±9.428; P<.0001) and RDD (mean=12.5± 8.267; P<.0001) patients, but not from FRS (mean=47.4±26.48; P>.05) patients. Similarly, the ratio of IgG4/IgG-positive plasmacytes was >40% in 90% (18/20) of IgG4-related CRS patients, compared to >40% in 10% (1/10) of GPA patients, 20% (2/10) of RDD patients and 20% (2/10) of FRS patients. The sinonasal diseases GPA, RDD and FRS might present with similar histopathologic features such as the increased numbers of plasma cells and fibrosis, which are characteristic of IgG4-related CRS. A comprehensive consideration combining the clinical signs and symptoms with a histopathological assessment of IgG4-positive plasma cells may provide accurate diagnoses of these conditions.

Xanthogranulomatous cholecystitis shows overlapping histological features with IgG4-related cholecystitis.

Xanthogranulomatous cholecystitis (XGC), an unusual histological variant of chronic cholecystitis, is characterised by mixed foamy histiocytic and lymphoplasmocytic infiltration and fibrosis. Radiologically, the poorly defined nodular growth pattern often leads to the misinterpretation of XGC as gallbladder cancer. In this study, we aimed to identify the relationship of XGC with IgG4-related cholecystitis. We re-evaluated 57 surgically resected XGCs and 104 conventional chronic cholecystitis cases, according to the histological features observed in IgG4-related disease, including lymphoplasmocytic infiltration, storiform fibrosis, obliterative phlebitis, and IgG4-positive plasma cells. XGCs contained a significantly increased mean number of IgG4-positive plasma cells [34.8/high-power field (HPF)] as compared with conventional chronic cholecystitis (4.8/HPF; P<0.001), and 16 XGCs (28%) harboured >50 IgG4-positive cells per HPF. Nine XGCs (16%), including one case with IgG4-related autoimmune pancreatitis, showed 'the histological features suggestive of IgG4-related disease', as described in the consensus statement regarding this condition. Extracholecystic inflammatory extension (seven cases, P=0.009) and mass-forming lesions (eight cases, P<0.001) were more frequently seen in XGC cases with histological features suggestive of IgG4-related disease than in cases without those microscopic changes. XGCs with IgG4-positive cell infiltration are considered to be mimickers, as xanthogranulomatous inflammation generally contradicts a diagnosis of IgG4-related disease and is weakly associated with other typical organ manifestations of IgG4-related disease. However, XGC may be a concurrent condition, particularly in patients with IgG4-related disease in other organs.

IgG4-related disease involving the esophagus: a clinicopathological study.

Immunoglobulin G4 (IgG4)-related disease is a recently coined systemic disease characterized by specific histopathologic findings of an intense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis in the presence of predominant IgG4-positive plasma cells. Although IgG4-related disease has been described in many organs, involvement of the esophagus is very rare. In this study, we describe the clinicopathologic characteristics of eight patients with IgG4-related esophagitis. We evaluated chronic esophagitis specimens with lymphoplasmacytic infiltrate obtained over the past 6 years (from January 2011 to February 2017) using a chart review, pathologic examination, and IgG4 immunohistochemical staining. The diagnoses of the specimens were either confirmed as IgG4-related esophagitis (IgG4-RE) or chronic esophagitis, not otherwise specified (CENOS), and the clinicopathologic data from each group were compared. Eight patients were diagnosed with IgG4-RE and 10 controls were identified and diagnosed with CENOS. In the IgG4-RE group, esophageal strictures were identified in three patients, two patients had postmyotomy treated achalasia, one patient had erosive esophagitis and another presented with an esophageal nodule. Only one patient had an unremarkable mucosa on endoscopy. In the CENOS group, four patients had esophageal strictures, six had erosive esophagitis, one patient had mild esophagitis. The IgG4-RE group had significantly higher numbers of IgG4-positive plasma cells (66.9±21.9 vs. 4.7±2.4 per high power field; P<0.001) and a greater IgG4: IgG ratio 0.76±0.13 vs. 0.06±0.05; P<0.001) when compared to CENOS patients. Two of the patients with recurrent esophageal strictures in the IgG4-RE group showed initial response to steroid therapy and are currently on immunosuppressive therapy which has significantly reduced the need for multiple esophageal dilatations. The presentation of IgG4-related esophageal disease can vary and the key to diagnosis is dependent on histopathology. These observations highlight the need for IgG4 immunohistochemical staining of esophageal biopsies especially in patients with mucosal ulceration, chronic inflammation, and plasmacytosis on biopsy. This will prevent unwarranted esophagectomies and failed medical treatment due to lack of recognition of this entity.

Clinicopathologic study of calcifying fibrous tumor of the gastrointestinal tract: a case series

Calcifying fibrous tumor (CFT) is a rare benign mesenchymal lesion known to arise at multiple body sites that may clinically mimic other more aggressive lesions in the gastrointestinal (GI) tract. In this study we describe the clinicopathologic findings of 28 GI tract CFTs. Tumors predominantly arose in middle-aged adults with a slight female predominance. The most commonly involved sites were small bowel and colon, followed by stomach and appendix. Tumors ranged from 0.3 to 9.3 cm (median 1.4 cm), and submucosa was the most commonly involved layer. All tumors were well circumscribed and unencapsulated. Microscopically, tumors were hypocellular and composed of spindle cells with abundant, haphazardly arranged hyalinized collagen. No necrosis and less than one mitosis per 10 HPF were identified in all cases. Calcification was present in most (81%) of the cases. All cases had lymphoplasmacytic inflammatory infiltrates either scattered throughout the lesion with occasional perivascular conglomeration or in the form of lymphoid aggregates. A lymphoplasmacytic cuff was usually present (81%). Immunostains showed variable CD34 immunoreactivity and variable numbers of IgG4-positive plasma cells. The lesional cells were negative for DOG-1, ALK-1, S100, C-kit, Sox10, Melan A, HMB45, desmin, CK7, and CK20, and showed cytoplasmic staining for β-catenin. Follow-up information was available in 5 cases with no recurrences reported to date (mean follow-up, 3 years). CFT is a rare benign tumor that can occur in part of the GI tract and should be distinguished from other mesenchymal tumors due to its low risk of recurrence.

Differential diagnosis of IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis

Our aim was to differentiate IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis by analysing clinical, radiographic, and pathological features. Fifty-five patients, 50, and 50 were enrolled, respectively and their baseline characteristics and serological, sialographic, and pathological findings compared. The male:female ratio for IgG4-related sialadenitis was 1:1.2 for primary Sjögren syndrome 1:15.7, and for chronic obstructive submandibular sialadenitis1:0.92. Numbers with enlarged salivary glands were 55, 16, and 50; with xerostomia 26, 48, and 0; with a history of allergy 26, 4, and 6, and with coexisting systemic disease 12, 19, and 0 (p=0.14). Mean (SD) serum IgG4 concentrations were 109.1 (97.9), 4.9. (1.9) g/L, and 5.3 (1.6) g/L, p<0.001 in all cases. Sialography showed enlargement of the gland, dilatation of the duct, and slightly decreased secretory function in IgG4-related disease; obvious sialectasia and decreased secretory function in Sjögren syndrome; and dilatation of Wharton’s duct and filling defects in obstructive sialadenitis. Histopathological examination showed lymphoplasmacytic infiltration with storiform fibrosis, lymphoplasmacytic inflammation and lymphoepithelial lesions, and dilatation of the duct with epithelial metaplasia in the three groups, respectively. The number of IgG4-positive plasma cells was 123 (45)/HPF, 8 (3)/HPF, and 5 (4)/HPF, while the IgG4-/IgG-positive cell ratio was 71.7 (13.9)%, 4.6 (2.5)%, 18.9 (19.7)%, respectively (p<0.001). The three conditions have different clinical, radiographic, and pathological features that provide important clues to the differential diagnosis. Serological and histological tests are important, and comprehensive consideration is necessary.

Increased number of IgG4-positive plasma cells in chronic rhinosinusitis

Conclusion: High levels of IgG4-positive plasma cells were observed in tissue samples from ∼30% of patients with chronic rhinosinusitis who satisfied the comprehensive diagnostic criteria for IgG4-related disease. Detection of increased numbers of IgG4-positive plasma cells in the nasal cavity or paranasal sinuses might not be sufficient to make a diagnosis of IgG4-related rhinosinusitis, and a comprehensive evaluation is required.Objectives: This study aimed to clarify the clinicopathological characteristics of IgG4-positive plasma cells in patients with chronic rhinosinusitis.Method: This study examined nasal mucosal specimens from 35 patients and assigned them to high-IgG4 and low-IgG4 groups based on infiltration of IgG4-positive plasma cells. It compared the pathological characteristics of the two groups, including the presence of fibrosis, phlebitis, hyperplasia of the nasal glands and infiltration of inflammatory cells.Results: No cases of chronic rhinosinusitis showed storiform fibrosis or obliterative phlebitis. The mean number of IgG4-positive plasma cells in samples from all patients was 29.8 ± 40.3/high-power field. Eleven of the 35 cases (31.4%) were classified as high-IgG4. Hyperplasia of the nasal glands was observed significantly more frequently in the high-IgG4 group than in the low-IgG4 group (p = .03).

An orphan disease: IgG4-related spinal pachymeningitis: report of 2 cases

IgG4-related disease is relatively new disease entity and a rare one, and our knowledge of this entity continues to evolve. It was first described in the pancreas and since then has been described in virtually every organ. Spinal involvement resulting in pachymeningitis is rare, and there are only 8 reported cases of the same to date, with the cervicothoracic spine being the most commonly affected region. The authors describe 2 cases in which the patients presented with spinal compression resulting in myeloradiculopathy (Case 1) and radiculopathy (Case 2). Imaging of spine in both cases revealed an ill-defined contrast-enhancing lesion at the lumbar level. Preoperatively, a diagnosis of spinal tumor was made, but intraoperatively no spinal tumor was found. The diagnosis was established histopathologically. The disease has no particular defining features clinically or radiologically and can mimic common spinal tumors. It is important to accurately diagnose this rare entity because of its multisystem involvement and progressive course. Strict treatment guidelines have yet to be formulated. Although histologically this disease can mimic other inflammatory conditions, the presence of storiform fibrosis and an increased number of IgG4-positive plasma cells can help in clarifying the diagnosis.

The diagnostic utility of labial salivary gland biopsy in IgG4-related disease

Objective: For the definitive diagnosis of IgG4-related disease (IgG4-RD), biopsies of local lesions are recommended so as to exclude other diseases, including lymphoma and cancer. However, performing biopsies of underlying organs is technically difficult. In this study, we examined the diagnostic utility of labial salivary gland (LSG) biopsy as a less invasive procedure.Methods: Sixty-six patients with suspected IgG4-RD by clinical findings or high serum IgG4 underwent LSG biopsy. We examined the relationship between the number of IgG4-positive plasma cells in LSG and clinical findings.Results: The final diagnosis was 45 patients with IgG4-RD, 12 with Sjögren’s syndrome, four with suspected Sjögren’s syndrome, three with malignant lymphoma, one with systemic lupus erythematosus, and one with Warthin’s tumor. The sensitivity, specificity, and accuracy of LSG biopsy were 55.6%, 100.0%, and 70.0%, respectively. Forty-five IgG4-RD patients were divided into two groups: 1) 25 with lesions of salivary glands (IgG4-RD S+) and 2) 20 without these lesions (IgG4-RD S−). Seventeen of 25 (68.0%) IgG4-RD S + and 8 of 20 (40.0%) IgG4-RD S − patients were positive for LSG biopsy. In the IgG4-RD S − patients, the mean number of affected organs and serum IgG4 in the positive cases for LSG biopsy were significantly higher than in the negative cases.Conclusion: A solo LSG biopsy is insufficient for the diagnosis of IgG4-RD because of its low sensitivity. However, LSG biopsy combined with clinical findings, including serum IgG4 and number of affected organs, may contribute towards a diagnosis of IgG4-RD patients with affected underlying organs.

Pulmonary pseudo-tumour, aortitis and IgG4 disease.

Learning point for clinicians A definitive diagnosis of IgG4-related disease is difficult in patients with intrathoracic or aortic lesions alone. Correlation with specific histopathological findings is essential, regardless of the serum IgG4 concentration, and the number of IgG4-positive plasma cells or the IgG4/IgG ratio in tissue. A 52-year-old man was admitted with a 1-year history of 20 kg weight loss and fatigue. He had no fever, night sweats, dyspnoea or cough. He had a 40 pack-year history of smoking and drank 50 g of alcohol per day. His past medical history was significant for hyperuricemia with gout episodes, mixed dyslipidaemia, obstructive sleep apnoea–hypopnoea syndrome and epileptic seizures. Physical examination was unremarkable. A chest X-ray showed an ill-defined mass-like lesion in the left upper lobe. His leucocyte count was 17.7 × 109/l, C-reactive protein 5.5 mg/dl and ESR 65 mm/1st h. Serum …