Usefulness of ultrasonography to assess the response to steroidal therapy for the rare case of type 2b immunoglobulin G4-related sclerosing cholangitis without pancreatitis:A case report

BACKGROUND A type 2b immunoglobulin G4(IgG4)-related sclerosing cholangitis(SC)without autoimmune pancreatitis is a rare condition with IgG4-SC.While the variety of the imaging modalities have tested its usefulness in diagnosing the IgG4-SC,however,the usage of ultrasonography for the assessment of the response to steroidal therapy on the changes of bile duct wall thickness have not been reported in the condition.Therefore,the information of our recent case and reported cases have been summarized.CASE SUMMARY We report the case of an 82-year-old Japanese man diagnosed with isolated IgG4-related SC based on the increase of serum IgG4,narrowing of the bile duct,its wall thickness,no complication of autoimmune pancreatitis,and IgG4 positive inflammatory cell infiltration to the wall with the fibrotic changes.The cholangiogram revealed type 2b according to the classification.Corticosteroid treatment showed a favorable effect,with the smooth decrease in serum IgG4 and the improvement of the bile duct wall thickness.CONCLUSION As isolated type 2b,IgG4-SC is rare,the images,histological findings,and clinical course of our case will be helpful for physicians to diagnose and treat the new cases appropriately.

Immunosuppressant treatment for IgG4-related sclerosing cholangitis: A case report

BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multi-system fibroinflammatory disorder that can involve any organ,including the salivary glands,pancreas,and biliary tree.Treatment of immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)is similar to that for IgG4-RD,but progression is irreversible in some cases.We present a case of IgG4-SC in which an immuno-suppressant induced marked clinical and radiologic improvement.CASE SUMMARY A 63-year-old male presented with a prominent itching sensation and wholebody jaundice.He showed obstructive-pattern jaundice,an elevated IgG4 level,and infiltration of a large number of IgG4-positive cells in the ampulla of Vater.The imaging findings of intrahepatic duct(IHD)and common bile duct dilation,an elevated serum IgG4 level,and characteristic histological findings led to diagnosis of IgG4-SC that compatible with the 2019 ACR/EULAR classification criteria.We planned to treat the patient with high-dose glucocorticoid(GC),followed by cyclophosphamide pulse therapy.After treatment with high-dose GC and an immunosuppressant,imaging studies showed that IHD dilatation had completely resolved.CONCLUSION Prompt diagnosis and appropriate treatment of IgG4-SC are important.Because there is a risk of relapse of IgG4-SC,the GC dose should be gradually reduced,and a maintenance immunosuppressant should be given.

Diagnosis of IgG4-related sclerosing cholangitis

IgG4-related sclerosing cholangitis(IgG4-SC)is often associated with autoimmune pancreatitis.However,the diffuse cholangiographic abnormalities observed in IgG4-SC may resemble those observed in primary sclerosing cholangitis(PSC),and the presence of segmental stenosis suggests cholangiocarcinoma(CC).IgG4-SC responds well to steroid therapy,whereas PSC is only effectively treated with liver transplantation and CC requires surgical intervention.Since IgG4-SC was first described,it has become a third distinct clinical entity of sclerosing cholangitis.The aim of this review was to introduce the diagnostic methods for IgG4-SC.IgG4-SC should be carefully diagnosed based on a combination of characteristic clinical,serological,morphological,and histopathological features after cholangiographic classification and targeting of a disease for differential diagnosis.When intrapancreatic stenosis is detected,pancreatic cancer or CC should be ruled out.If multiple intrahepatic stenoses are evident,PSC should be distinguished on the basis of cholangiographic findings and liver biopsy with IgG4 immunostaining.Associated inflammatory bowel disease is suggestive of PSC.If stenosis is demonstrated in the hepatic hilar region,CC should be discriminated by ultrasonography,intraductal ultrasonography,bile duct biopsy,and a higher cutoff serum IgG4 level of 182 mg/dL.

First case of IgG4-related sclerosing cholangitis associated with autoimmune hemolytic anemia

To our knowledge,patients with immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)associated with autoimmune hemolytic anemia(AIHA)have not been reported previously.Many patients with IgG4-SC have autoimmune pancreatitis(AIP)and respond to steroid treatment.However,isolated cases of IgG4-SC are difficult to diagnose.We describe our experience with a patient who had IgG4-SC without AIP in whom the presence of AIHA led to diagnosis.The patient was a73-year-old man who was being treated for dementia.Liver dysfunction was diagnosed on blood tests at another hospital.Imaging studies suggested the presence of carcinoma of the hepatic hilus and primary sclerosing cholangitis,but a rapidly progressing anemia developed simultaneously.After the diagnosis of AIHA,steroid treatment was begun,and the biliary stricture improved.IgG4-SC without AIP was thus diagnosed.

Isolated intrapancreatic Ig G4-related sclerosing cholangitis

Immunoglobulin G4-related sclerosing cholangitis(Ig G4-SC) is frequently associated with type 1 autoimmune pancreatitis(AIP). Association with AIP can be utilized in the diagnosis of Ig G4-SC. However, some cases of Ig G4-SC are isolated from AIP, which complicates the diagnosis. Most of the reported cases of isolated Ig G4-SC displayed hilar biliary strictures, whereas isolated Ig G4-SC with intrapancreatic biliary stricture is very rare. Recently, we have encountered 5 isolated intrapancreatic Ig G4-SC cases that were not associated with AIP, three of which were pathologically investigated after surgical operation. They all were males with a mean age of 74.2 years. The pancreas was not enlarged in any of these cases. No irregular narrowing of the main pancreatic duct was found. Bile duct wall thickening in lesions without luminal stenosis was detected by abdominal computed tomography in all five cases, by endoscopic ultrasonography in two out of four cases and by intraductal ultrasonography in all three cases. In three cases, serum Ig G4 levels were within the normal limits. The mean serum Ig G4 level measured before surgery was 202.1 mg/d L(4 cases). Isolated intrapancreatic Ig G4-SC is difficult to diagnose, especially if the Ig G4 level remains normal. Thus, this type of Ig G4-SC should be suspected in addition to cholangiocarcinoma and pancreatic cancer if stenosis of intrapancreatic bile duct is present.

IgG4-related sclerosing cholangitis and chronic sclerosing sialadenitis mimicking cholangiocarcinoma and neck malignancy

To the Editor:IgG4-related sclerosing cholangitis（IgG4-SC）has re cently been recognized as a biliary manifestation of IgG4-related disease（IgG4-RD）.Type 3 IgG4-SC pre sented biliary strictures in both the porta hepatis and the distal common bile duct（CBD）.;Its manifestation especially in the absence of autoimmune pancreatitis,is extremely rare and very similar to that of cholangiocarci noma（CC）.

Infrequent organ involvement in immunoglobulin G4-related prostate disease: A case report

BACKGROUND Immunoglobulin G4-related prostate disease(IgG4-RPD)characterized by a high count of IgG4-positive plasma cells has distinctive serological and radiological findings.Here we report a case of a patient who was successfully treated for IgG4-RPD,which manifested as frequent micturition,dysuric,and systemic lymphadenopathy.CASE SUMMARY The patient was a 33-year-old man who was referred to our hospital because of urinary tract symptoms that had persisted for 4 years.A physical examination revealed systemic lymphadenopathy and blood tests showed hyperglobulinemia with an IgG level of 18.90 g/L and an IgG4 level of 18.40 g/L.Computed tomography(CT)revealed bilateral lacrimal gland,right parotid gland and prostatic enlargement.Based on these findings,IgG4-RD was suspected,and further pathological examination and follow-up results showed expected results.Finally,the patient was diagnosed with IgG4-RPD based on clinical symptoms,pathological examination,therapeutic effects,and follow-up results.He received 50 mg oral prednisolone(the dose was gradually reduced and a low dose was used for long-term maintenance)in combination with cyclophosphamide 1.0 g via an intravenous drip for 6 mo.One year after the treatment was initiated,he was free of urinary or other complaints and his serum IgG4 level normalized.CONCLUSION In IgG4-RPD with severe urinary tract symptoms,radiological findings should be carefully examined.IgG4-RPD prognosis is good because the disease responds well to glucocorticoids.Furthermore,it is urgent for clinicians and pathologists to improve their understanding of IgG4-RPD.

Review of primary sclerosing cholangitis with increased IgG4 levels

Primary sclerosing cholangitis(PSC) is a chronic progressive liver disease. Subtypes of PSC have been described, most recently PSC with elevated serum and/or tissue IgG4 subclass. We aim to summarise the clinical phenotype,disease associations, differential diagnosis, response to therapy and pathogenic mechanisms underlying PSC-high IgG4 subtype. We reviewed Pub Med,MEDLINE and Embase with the search terms "primary sclerosing cholangitis","IgG4", and "IgG4-related sclerosing cholangitis(IgG4-SC)". Elevated serum IgG4 are found in up-to one-quarter, and abundant IgG4-plasma cell infiltrates in the liver and bile ducts are found in up-to one-fifth of PSC patients. This group have a distinct clinical phenotype, with some studies reporting a more aggressive course of liver and associated inflammatory bowel disease, compared to PSCnormal IgG4 and the disease mimic IgG4-SC. Distinguishing PSC-high IgG4 from IgG4-SC remains challenging, requiring careful assessment of clinical features,organ involvement and tissue morphology. Calculation of serum IgG4:IgG1 ratios and use of a novel IgG4:IgG RNA ratio have been reported to have excellent specificity to distinguish IgG4-SC and PSC-high IgG4 but require validation in larger cohorts. A role for corticosteroid therapy in PSC-high IgG4 remains unanswered, with concerns of increased toxicity and lack of outcome data. The immunological drivers underlying prominent IgG4 antibodies in PSC are incompletely defined. An association with PSC-high IgG4 and HLA class-II haplotypes(B*07, DRB1*15), T-helper2 and T-regulatory cytokines(IL4, IL10,IL13) and chemokines(CCL1, CCR8) have been described. PSC-high IgG4 have a distinct clinical phenotype and need careful discrimination from IgG4-SC,although response to immunosuppressive treatments and long-term outcome remains unresolved. The presence of IgG4 likely represents chronic activation to persistent antigenic exposure in genetically predisposed individuals.

Biomarkers in autoimmune pancreatitis and immunoglobulin G4-related disease

Solitary organ autoimmune disorders,formerly known as autoimmune pancreatitis(AIP),autoimmune sialadenitis,and autoimmune sclerosing cholangitis,are now considered organ-specific manifestations of systemic immunoglobulin G4-related disease(IgG4-RD).AIP and IgG4-RD are characterized by elevated serum concentration of IgG4 antibody(Ab),accumulation of IgG4-expressing plasmacytes in the affected organs,and involvement of multiple organs.It is well established that enhanced IgG4 Ab responses are a hallmark of AIP and IgG4-RD for diagnosis and monitoring disease activity.However,a significant fraction of patients with AIP and IgG4-RD who develop chronic fibroinflammatory responses have normal serum concentrations of this IgG subtype.In addition,disease flare-up is sometimes seen even in the presence of normalized serum concentrations of IgG4 Ab after successful induction of remission by prednisolone.Therefore,it is necessary to identify new biomarkers based on the understanding of the pathophysiology of AIP and IgG4-RD.Recently,we found that activation of plasmacytoid dendritic cells producing both interferon-α(IFN-α)and interleukin-33(IL-33)mediate murine AIP and human IgG4-RD.More importantly,we provided evidence that serum concentrations of IFN-αand IL-33 could be useful biomarkers for the diagnosis and monitoring of AIP and IgG4-RD activity after induction of remission in these autoimmune disorders.In this Frontier article,we have summarized and discussed biomarkers of AIP and IgG4-RD,including Igs,autoAbs,and cytokines to provide useful information not only for clinicians but also for researchers.

Immunoglobulin G4-related kidney diseases: An updated review

This review will encompass definition, pathogenesis, renal clinical manifestations and treatment of immunoglobulin G4-related diseases( IgG4-RDs). IgG4-RD is a recently recognized clinical entity that often involves multiple organs and is characterized by high levels of serum immunoglobulins G4, dense infiltration of IgG4+ cells and storiform fibrosis. Cellular immunity, particularly T-cell mediated immunity, has been implicated in the pathogenesis of IgG4-RDs. The most frequent renal manifestations of IgG4-RD are IgG4-related tubulointerstitial nephritis, membranous glomerulopathy and obstructive nephropathy secondary to urinary tract obstruction due to IgG4-related retroperitoneal fibrosis. IgG4-RD diagnosis should be based on specific histopathological findings, confirmed by tissue immunostaining, typical radiological findings and an appropriate clinical context. The first line treatment is the steroids with two warnings: Steroid resistance and relapse after discontinuation. In the case of steroid resistance, B cell depleting agents as rituximab represent the secondline treatment. In the case of relapse after discontinuation, steroid treatment may be associated with steroid sparing agents. Since the disease has been only recently identified, more prospective, long-term studies are needed to an improved understanding and a more correct and safe treatment.

Immunoglobulin G4-related autoimmune pancreatitis and sialadenitis: A case report

Immunoglobulin G4(Ig G4)-related disease is a rare systemic diseases. A 67-year-old male presented at our institution with mild upper abdominal pain and jaundice for 20 d. Laboratory results revealed high levels of Ig G4(15.4 g/L,range: 0.08-1.4 g/L). Computed tomography(CT) showed significant enlargement of the entire pancreas and a capsule-like low-density rim surrounding the whole pancreas. Positron emission tomography/CT revealed increased uneven metabolism of the entire pancreas. Both magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography showed stenosis of the distal common bile duct and proximal main pancreatic duct,and dilation of the proximal common bile duct and extra- and intra-hepatic bile ducts. He was diagnosed with Ig G4-related autoimmune pancreatitis. The patient was treated with prednisone for 14 mo. The patient responded well to prednisone but upon cessation of the corticosteroid developed enlargement of the submandibular gland. The patient's serum Ig G4 was elevated at 23.9 g/L. It is important to maintain treatment,so the patient was again treated with prednisone and had a good response. Follow-up of Ig G4-related disease is thus necessary.

Successful treatment of tubulointerstitial nephritis in immunoglobulin G4-related disease with rituximab: A case report

BACKGROUND Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated condition that consisted of disorders that share particular clinical,serologic and pathologic properties.The common presentation of disease includes tumor-like swelling of involved organs and the histopathological findings are a lymphoplasmacytic infiltrate enriched with IgG4-positive plasma cells,and a variable degree of fibrosis that has a characteristic "storiform" pattern in biopsy specimens of tumorlike masses.Major presentations of this disease,which often affects more than one organ,include autoimmune pancreatitis,salivary gland disease (sialadenitis),orbital disease and retroperitoneal fibrosis.The steroid treatment is essential for the treatment of the disease however,other immunosuppressive drugs including cyclophosphamide or rituximab could be an option in resistant cases.CASE SUMMARY Herein,we reported a 34-year-old woman whom previously had diagnosed with asthma,rheumatoid arthritis and Sj?gren’s syndrome (SS) referred our nephrology department due to acute kidney failure development at the last rheumatology visit.After kidney biopsy she has been diagnosed with IgG4-RD and tubuluointerstitial nephritis.She had been accepted resistant to steroid,mycophenolate mofetil,methotrexate and azathioprine therapies due to receiving in last two years.She refused to receive cyclophosphamide due to potential gonadotoxicity of the drug.Thus,rituximab therapy was considered.She received 1000 mg infusion,15 d apart and 6 mo later it has been administered same protocol.After one year from the last rituximab dose serum creatinine decreased from 4.4 mg/dL to 1.6 mg/dL,erythrocyte sedimentation rate decreased from 109 mm/h to 13 mm/h [reference range (RR) 0-20],and Creactive protein decreased from 55.6 mg/L to 5 mg/L (RR 0–6).All pathologic lymph nodes and masses were also disappeared.CONCLUSION Patients with IgG4-RD usually misdiagnosed with rheumatologic diseases including systemic lupus erythematous or SS and also they were screened for the presence of malignancy.Rituximab could be an important treatment option in cases with steroid resistant tubulointerstitial nephritis in IgG4-RD.

Immunoglobulin G4 associated autoimmune cholangitis and pancreatitis following the administration of nivolumab:A case report

BACKGROUND Immune checkpoint inhibitors have significantly improved survivals for an increasing range of malignancies but at the cost of several immune-related adverse events,the management of which can be challenging due to its mimicry of other autoimmune related disorders such as immunoglobulin G4(IgG4)related disease when the pancreaticobiliary system is affected.Nivolumab,an IgG4 monoclonal antibody,has been associated with cholangitis and pancreatitis,however its association with IgG4 related disease has not been reported to date.CASE SUMMARY We present a case of immune-related pancreatitis and cholangiopathy in a patient who completed treatment with nivolumab for anal squamous cell carcinoma.Patients IgG4 levels was normal on presentation.She responded to steroids but due to concerns for malignant biliary stricture,she opted for surgery,the pathology of which suggested IgG4 related disease.CONCLUSION We hypothesize this case of IgG4 related cholangitis and pancreatitis was likely triggered by nivolumab.

Progressive multi-organ expression of immunoglobulin G4-related disease: A case report

A 63-year-old Caucasian man presented with a cholestatic syndrome, renal failure and arthralgias. A laboratory examination revealed high immunoglobulin G (IgG) and IgG4 levels (5.95 g/L; normal range: 0.08-1.4 g/L), pointing to a diagnosis of systemic IgG4-related disease, with definite radiological evidence of biliary and pancreatic expression, and plausible renal, articular, salivary and lacrimal glands involvement. Due to the rarity of the condition, there are currently no random control trials to point to the optimal therapeutic approach. The patient has been on steroid therapy with the subsequent introduction of azathioprine, with a complete resolution of all symptoms, a rapid reduction to normalization of all blood tests, and a complete regression of the radiological picture. Our experience underlines the complexity of IgG4-related disease and its variable and sometimes progressive presentation, while pointing out the need for a careful and complete assessment for possible multi-organ involvement.

Immunoglobulin G4 associated autoimmune cholangitis and pancreatitis and nivolumab

This letter to editor discussing on the publication on immunoglobulin G4 associated autoimmune cholangitis and pancreatitis following the administration of nivolumab.Concerns on confounding factors are raised and discussed.

Immunoglobulin G4-related kidney disease involving the renal pelvis and perirenal fat:A case report

BACKGROUND Immunoglobulin(Ig)G4-related disease(Ig G4-RD)is an autoimmune disease associated with chronic and progressive inflammation and fibrosis.It is difficult to differentiate Ig G4-RD involving the kidney from infectious diseases and malignancy on imaging.CASE SUMMARY We report the case of a 51-year-old Chinese man whose abdominal computed tomography scan showed diffuse bilateral enlargement of the kidneys and perirenal fat,thickening of the renal pelvic walls,and hydronephrosis of the right kidney.Relevant laboratory test results showed a serum creatinine level of 464μmol/L.The patient was diagnosed with acute renal failure and was started on intermittent hemodialysis.Further tests revealed high serum Ig G4 levels(20.8 g/L)and an enlarged right submaxillary lymph node.Biopsy and histopathological examination of the enlarged node led to the diagnosis of Ig G4-RD.After corticosteroid therapy,his serum creatinine level quickly decreased to near normal levels.CONCLUSION Ig G4-RD affecting the renal pelvis or perirenal fat is rare,with atypical imaging features.Multidisciplinary consultation is critical for accurate diagnosis and treatment of this disease.Suspected cases should undergo biopsy to avoid misdiagnosis.

Immunoglobulin G4-related disease in the sigmoid colon in patient with severe colonic fibrosis and obstruction:A case report

BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is an immune-mediated condition characterized by abundant IgG4 positive plasma cells and fibrosis in the affected tissues.It affects most parts of the body;however,there are not many reports on IgG4-RD involving the colon.CASE SUMMARY A 50-year-old man complaining of intermittent fever for more than two years was referred to our hospital.Based on various investigations before surgery,we diagnosed him with chronic perforation of the sigmoid colon caused by inflammatory change or tumor.IgG blood tests before the operation suggested IgG4-RD,and postoperative pathology confirmed this prediction.CONCLUSION We present a patient with IgG4-RD with colon involvement,which is an uncommon site.This report will expand the understanding of IgG4-RD in unknown tissues.

IgG4-Related Disease:A Retrospective Chinese Study of Features and Treatment Response of 98 Patients Including 4 Rare Cases

The features and treatment of 98 Chinese patients with immunoglobulin G4 (IgG4)-related disease (IgG4-RD) referred to a single tertiary referring centre were reviewed. Patientsdiagnosed with IgG4-RD according to the comprehensive diagnostic criteria (CDC) were includedin the retrospective study from May 2012 to March 2019. We collcted data on clinical, laboratory,imaging, histological features and treatment. Totally, 98 patients with IgG4-RD were enrolled.The common clinical manifestations included abdominal pain, salivary gland swelling andlymphadenopathy. 51% of the patients had multiple organs involvement. Lymph nodes, pancreasand salivary glands were most commonly involved. Four rare sites including ulna, cerebellum,scalp, and mammary gland were found. The serum IgG4 level was increased by 85.7%. The serumIgG4 level was positively correlated with the number of involved organs, IgG and IgG4/IgG. LowC3 and C4 levels were observed in 37.5% and 12.2% patients respectively, and all patients withkidney involvement had hypocomplementemia. A total of 54 patients underwent tissue biopsies,and 55.6%, 31.5% and 11.1% cases were diagnosed as definite, probable and possible IgG4-RD,respectively. Eighty-eight patients received glucocorticoids (GCs) therapy. Five patients underwentradical surgery to remove the lesion. 73% of them presented a complete or partial remission. IgG4-RD is a systemic fibroinflammatory disease with involvement of multiple organs throughout thebody including some rare sites. Most IgG4-RD patients had increased serum IgG4 levels andpatients with kidney involvement showed bypocomplementermia. GCs therapy is effective. Moreresearch is needed to provide a more reliable basis for the diagnosis and treatment of patients.

Clinical and pathological differences between serum immunoglobulin G4-positive and -negative type 1 autoimmune pancreatitis

AIM: To identify clinical and pathological differences between serum immunoglobulin G4 (IgG4)-positive (SIP) and IgG4-negative (SIN) type 1 autoimmune pancreatitis (AIP) in South Korea. METHODS: AIP was diagnosed by the international consensus diagnostic criteria. The medical records and pathology were retrospectively reviewed and IgG4-positive cells were counted in a high power field (HPF). Type I AIP was defined as a high serum level of IgG4or histological finding. SIN type 1 AIP was defined as a histological evidence of type 1 AIP and a normal serum IgG4 level. The clinical and pathological findings were compared between the two groups. The analysis was performed using Student's t test, Fischer's exact test and Mann-Whitney's U test. A P value of < 0.05 was considered statistically significant. As repeated com- parison was made, P values of less than 5% (P < 0.05) were considered significant. RESULTS: Twenty five patients with definite type 1 AIP (19 histologically and six serologically diagnosed cases) were enrolled. The mean tissue IgG4 concentrations were significantly higher in SIP than SIN group (40 cells per HPF vs 18 cells per HPF, P = 0.02). Among eight SIN patients, the tissue IgG4 concentrations were less than 15 cells per HPF in most of cases, except one. The sensitivity of serum IgG4 was 68% (17 SIP and eight SIN AIP). Other organ involvement was more frequent- ly associated with SIP than SIN AIP (59% vs 26%, P = 0.016). However, the relapse rate and diffuse swelling of the pancreas were not associated with serum IgG4 level. The concentrations of IgG4-positive cells per HPF were higher in SIP than SIN AIP (40 vs 18, P = 0.02). CONCLUSION: The sensitivity of serum IgG4 was 68% in type 1 AIP. High serum IgG4 level was associated with other organ involvement and tissue IgG4 concentration but did not affect the relapse rate in type 1 AIP.

Understanding autoimmune pancreatitis: Clinical features, management challenges, and association with malignancies

In this editorial we comment on the article by Jaber et al.Autoimmune pancreatitis(AIP)represents a distinct form of pancreatitis,categorized into AIP-1 and AIP-2,characterized by obstructive jaundice,lymphoplasmacytic infiltrate,and fibrosis.AIP-1,associated with elevated immunoglobulin G4(IgG4)levels,exhibits higher relapse rates,affecting older males,while AIP-2 is less common and linked to inflammatory bowel disease.AIP is considered a manifestation of IgG4-related systemic disease,sharing characteristic histological findings.Steroids are the primary treatment,with emerging biomarkers like interferon alpha and inter-leukin-33.AIP poses an increased risk of various malignancies,and the assoc-iation with pancreatic cancer is debated.Surgery is reserved for severe cases,necessitating careful evaluation due to diagnostic challenges.AIP patients may have concurrent PanINs but display favorable long-term outcomes compared to pancreatic cancer patients.Thorough diagnostic assessment,including biopsy and steroid response,is crucial for informed surgical decisions in AIP.