A simpler diagnostic algorithm of the Japan Esophageal Society classification for Barrett's esophagus-related superficial neoplasia.

BACKGROUND: We previously developed a Japan Esophageal Society Barrett's Esophagus (JES-BE) magnifying endoscopic classification for superficial BE-related neoplasms (BERN) and validated it in a nationwide multicenter study that followed a diagnostic flow chart based on mucosal and vascular patterns (MP, VP) with nine diagnostic criteria. Our present post hoc analysis aims to further simplify the diagnostic criteria for superficial BERN. METHODS: We used data from our previous study, including 10 reviewers' assessments for 156 images of high-magnifying narrow-band imaging (HM-NBI) (67 dysplastic and 89 non-dysplastic histology). We statistically analyzed the diagnostic performance of each diagnostic criterion of MP (form, size, arrangement, density, and white zone), VP (form, caliber change, location, and greenish thick vessels [GTV]), and all their combinations to achieve a simpler diagnostic algorithm to detect superficial BERN. RESULTS: Diagnostic accuracy values based on the MP of each single criterion or combined criteria showed a marked trend of being higher than those based on VP. In reviewers' assessments of visible MPs, the combination of irregularity for form, size, or white zone had the highest diagnostic performance, with a sensitivity of 87% and a specificity of 91% for dysplastic histology; in the assessments of invisible MPs, GTV had the highest diagnostic performance among the VP of each single criterion and all combinations of two or more criteria (sensitivity, 93%; specificity, 92%). CONCLUSION: The present post hoc analysis suggests the feasibility of further simplifying the diagnostic algorithm of the JES-BE classification. Further studies in a practical setting are required to validate these results.

Endoscopic Diagnosis and Therapy for Epstein-Barr Virus-Associated Gastric Cancer.

Epstein-Barr-virus-associated gastric cancer (EBVaGC) represents almost 7% of all GC and is a distinct subtype of GC with extreme DNA hypermethylation. EBVaGC is a tumor-infiltrating lymphocyte-rich tumor with little lymph-node metastasis in its early stage and with a relatively favorable prognosis in its advanced stage. Using upper gastrointestinal endoscopy, we recognize EBVaGC as a mainly depressed type with SMT-like protrusion in the upper part of the stomach near the gastric mucosal atrophic border or remnant stomach. The EBVaGC recognition rate of 21.4% with the endoscopic motif is not high, and further progress in endoscopic diagnosis of EBVaGC is needed. As less invasive endoscopic therapy, the extension of the criteria of endoscopic submucosal dissection (ESD) for early EBVaGC with little lymph-node metastasis should be discussed. Endoscopic diagnosis of EBVaGC may be relevant for the selection of patients who could benefit from endoscopic treatment or chemotherapy.

Usefulness of cardiac magnetic resonance for early detection of cancer therapeutics-related cardiac dysfunction in breast cancer patients.

BACKGROUND: Prognosis of breast cancer patients has been improved along with the progress in cancer therapies. However, cancer therapeutics-related cardiac dysfunction (CTRCD) has been an emerging issue. For early detection of CTRCD, we examined whether native T1 mapping and global longitudinal strain (GLS) using cardiac magnetic resonance (CMR) and biomarkers analysis are useful. METHODS: We prospectively enrolled 83 consecutive chemotherapy-naïve female patients with breast cancer (mean age, 56 ± 13 yrs.) between 2017 and 2020. CTRCD was defined based on echocardiography as left ventricular ejection fraction (LVEF) below 53% at any follow-up period with LVEF>10% points decrease from baseline after chemotherapy. To evaluate cardiac function, CMR (at baseline and 6 months), 12­lead ECG, echocardiography, and biomarkers (at baseline and every 3 months) were evaluated. RESULTS: A total of 164 CMRs were performed in 83 patients. LVEF and GLS were significantly decreased after chemotherapy (LVEF, from 71.2 ± 4.4 to 67.6 ± 5.8%; GLS, from -27.9 ± 3.9 to -24.7 ± 3.5%, respectively, both P < 0.01). Native T1 value also significantly elevated after chemotherapy (from 1283 ± 36 to 1308 ± 39 msec, P < 0.01). Among the 83 patients, 7 (8.4%) developed CTRCD. Of note, native T1 value before chemotherapy was significantly higher in patients with CTRCD than in those without it (1352 ± 29 vs. 1278 ± 30 msec, P < 0.01). The multivariable logistic regression analysis revealed that native T1 value was an independent predictive factor for the development of CTRCD [OR 2.33; 95%CI 1.15-4.75, P = 0.02]. CONCLUSIONS: These results indicate that CMR is useful to detect chemotherapy-related myocardial damage and predict for the development of CTRCD in breast cancer patients.

Effect of chemoradiation on the development of second primary cancers after endoscopic resection of T1 esophageal squamous cell carcinoma.

BACKGROUND: Patients with early esophageal squamous cell carcinoma (ESCC) may develop multiple second primary ESCC and cancers in other organs even after curative endoscopic resection (ER). We investigated whether administration of chemoradiotherapy (CRT) after ER decreases the incidence of second primary cancers. METHODS: We conducted a post hoc analysis of the prospective study. Among the registered 170 patients with clinical submucosal ESCC, 74 underwent ER alone, and 96 underwent ER followed by CRT (ER + CRT) because of pathological results of submucosal or lympho-vascular invasion. We compared the incidence of second primary cancers in esophagus and in other organs between two treatment groups. A univariate analysis was performed to investigate the related risk factors. All patients were followed up with esophagogastroduodenoscopy and CT every 4 months for the first 3 years and every 6 months thereafter. RESULTS: Sixty-one ESCC were detected in 32 patients, and the 3-year cumulative incidence of multiple ESCCs was not different between ER + CRT and ER alone (10.4% vs. 13.5%). Sixty-three second primary cancers in other organs were detected in 45 patients, and there was no difference in the cumulative incidence between two groups. The risk factors for multiple ESCCs were high alcohol consumption and grade C multiple Lugol-voiding lesions. Heavy drinker or patients with grade C multiple Lugol-voiding lesion rather than CRT were at risk for second primary ESCC. CONCLUSION: CRT after ER did not decrease the cumulative incidence of second primary ESCC nor cancers in other organs comparing with ER alone.

Usefulness of Right Ventricular Free Wall Strain Obtained with Two-Dimensional Speckle-Tracking Echocardiography in Patients with Repaired Tetralogy of Fallot and Pulmonary Regurgitation.

Right ventricular (RV) dysfunction caused by chronic pulmonary regurgitation (PR) is a major determinant of clinical outcome in adults with repaired tetralogy of Fallot (rTOF). However, the accurate assessment of RV function by conventional echocardiography remains challenging. This study tested the feasibility and usefulness of RV free-wall (RVFW) strain obtained by two-dimensional (2D) speckle-tracking echocardiography (STE) in evaluation of RV function in adults with rTOF by comparing cardiac magnetic resonance (CMR) imaging. We enrolled 22 consecutive patients (male/female, 8/14; mean age, 25.0 years) with rTOF who underwent transthoracic echocardiography at Tohoku University Hospital from July 2016 to June 2019. We measured RVFW strain by STE and compared them with 22 hemodynamically normal subjects (NOR) (male/female, 9/13; mean age, 32.0 years). The correlation between RV strain and CMR-derived RV ejection fraction (RVEF) or PR fraction (PRF) were also evaluated. All rTOF patients had more than moderate PR but were near asymptomatic. RVFW longitudinal strain (RVFW-LS) was significantly decreased in the rTOF group compared with that in the NOR group (-19.6 vs. -24.7, P < 0.01). In the rTOF group, RVFW-LS correlated with PRF (r = 0.44, P < 0.05), whereas RVFW circumferential strain at the mid-ventricular level correlated with RVEF (r = 0.57, P < 0.01). Intra-observer variability of RVFW strain was acceptable. These results indicate that RV systolic function and PR severity in rTOF could be assessed by RVFW strain measured by 2D STE. This method is feasible and can be used as a complement to CMR imaging.

Diagnostic utility of a novel magnifying endoscopic classification system for superficial Barrett's esophagus-related neoplasms: a nationwide multicenter study.

BACKGROUND: Currently, no classification system using magnification endoscopy for the diagnosis of superficial Barrett's esophagus (BE)-related neoplasia has been widely accepted. This nationwide multicenter study aimed to validate the diagnostic accuracy and reproducibility of the magnification endoscopy classification system, including the diagnostic flowchart developed by the Japan Esophageal Society-Barrett's esophagus working group (JES-BE) for superficial Barrett's esophagus-related neoplasms. METHODS: The JES-BE acquired high-definition magnification narrow-band imaging (HM-NBI) images of non-dysplastic and dysplastic BE from 10 domestic institutions. A total of 186 high-quality HM-NBI images were selected. Thirty images were used for the training phase and 156 for the validation (test) phase. We invited five non-experts and five expert reviewers. In the training phase, the reviewers discussed how to correctly predict the histology based on the JES-BE criteria. In the validation phase, they evaluated whether the criteria accurately predicted the histology results according to the diagnostic flowchart. The validation phase was performed immediately after the training phase and at 6 weeks thereafter. RESULTS: The sensitivity and specificity for all reviewers were 87% and 97%, respectively. Overall accuracy, positive predictive value, and negative predictive value were 91%, 98%, and 83%, respectively. The overall strength of inter-observer and intra-observer agreements for dysplastic histology prediction was κ = 0.77 and κ = 0.83, respectively. No significant difference in diagnostic accuracy and reproducibility between experts and non-experts was found. CONCLUSION: The JES-BE classification system, including the diagnostic flowchart for predicting dysplastic BE, is acceptable and reliable, regardless of the clinician's experience level.

Efficacy of Endoscopic Resection and Selective Chemoradiotherapy for Stage I Esophageal Squamous Cell Carcinoma.

BACKGROUND & AIMS: Esophagectomy is the standard treatment for stage I esophageal squamous cell carcinoma (ESCC). We conducted a single-arm prospective study to confirm the efficacy and safety of selective chemoradiotherapy (CRT) based on findings from endoscopic resection (ER). METHODS: We performed a prospective study of patients with T1b (SM1-2) N0M0 thoracic ESCC from December 2006 through July 2012; 176 patients underwent ER. Based on the findings from ER, patients received the following: no additional treatment for patients with pT1a tumors with a negative resection margin and no lymphovascular invasion (group A); prophylactic CRT with 41.4 Gy delivered to locoregional lymph nodes for patients with pT1b tumors with a negative resection margin or pT1a tumors with lymphovascular invasion (group B); or definitive CRT (50.4 Gy) with a 9-Gy boost to the primary site for patients with a positive vertical resection margin (group C). Chemotherapy comprised 5-fluorouracil and cisplatin. The primary end point was 3-year overall survival in group B, and the key secondary end point was 3-year overall survival for all patients. If lower limits of 90% confidence intervals for the primary and key secondary end points exceeded the 80% threshold, the efficacy of combined ER and selective CRT was confirmed. RESULTS: Based on the results from pathology analysis, 74, 87, and 15 patients were categorized into groups A, B, and C, respectively. The 3-year overall survival rates were 90.7% for group B (90% confidence interval, 84.0%-94.7%) and 92.6% in all patients (90% confidence interval, 88.5%-95.2%). CONCLUSIONS: In a prospective study of patients with T1b (SM1-2) N0M0 thoracic ESCC, we confirmed the efficacy of the combination of ER and selective CRT. Efficacy is comparable to that of surgery, and the combination of ER and selective CRT should be considered as a minimally invasive treatment option. UMIN-Clinical Trials Registry no.: UMIN000000553.

Newly developed magnifying endoscopic classification of the Japan Esophageal Society to identify superficial Barrett's esophagus-related neoplasms.

AIM AND METHODS: The Japan Esophageal Society created a working committee group consisting of 11 expert endoscopists and 2 pathologists with expertise in Barrett's esophagus (BE) and esophageal adenocarcinoma. The group developed a consensus-based classification for the diagnosis of superficial BE-related neoplasms using magnifying endoscopy. RESULTS: The classification has three characteristics: simplified, an easily understood classification by incorporating the diagnostic criteria for the early gastric cancer, including the white zone and demarcation line, and the presence of a modified flat pattern corresponding to non-dysplastic histology by adding novel diagnostic criteria. Magnifying endoscopic findings are composed of mucosal and vascular patterns, and are initially classified as "visible" or "invisible." Morphologic features were evaluated for "visible" patterns, and were subsequently rated as "regular" or "irregular," and the histology, non-dysplastic or dysplastic, was predicted. CONCLUSION: We introduce the process and outline of the magnifying endoscopic classification.

Fracture of a Colonic Self-expandable Metallic Stent in Malignant Colonic Obstruction.

Self-expandable metallic stents (SEMSs) are used for the management of malignant colorectal obstruction. A patient who underwent colonic uncovered SEMS insertion for extraluminal stenosis in the splenic flexure of the transverse colon due to advanced gastric cancer is herein reported. The patient presented with a fracture of the colonic SEMS 494 days after SEMS insertion. Although various complications of stenting have previously been reported, the details of fractures of colonic SEMSs have not yet been reported. Because the improvement in the prognosis for patients who undergo palliative SEMS insertion leads to long-term SEMS placement, diverse complications can thus be expected, and new events like stent fracture are expected to increase in the future.

Left Recumbent Position Decreases Heart Rate without Alterations in Cardiac Autonomic Nervous System Activity in Healthy Young Adults.

Some studies have reported that recumbent position may have advantages in patients with heart disease and in pregnancy. However, it remains controversial whether recumbent position affects autonomic nervous system activity and hemodynamics in healthy adults. The aim of this study was to evaluate alterations in heart rate variability (HRV) and hemodynamics in the supine, left recumbent and right recumbent positions in healthy young adults. A total of 80 participants aged 22.8 ± 3.1 years were enrolled in this observational study. Fifty-eight volunteers (29 men and 29 women) maintained the supine position followed by the left and right recumbent positions, while electrocardiographic data were recorded for spectral analysis of HRV to assess cardiac vagal nerve and sympathetic nerve activities. The heart rate (HR) was significantly lower in the left recumbent position than in the other positions. There were no statistically significant differences in HRV among the three positions. Considering the possibility that the echographic procedure affects autonomic nervous system (ANS) activity, the other 22 participants (11 men and 11 women) underwent an echographic evaluation of hemodynamics in the heart and inferior vena cava (IVC) across the three positions. Although a low HR was also observed, there were no statistically significant differences in the IVC or the heart blood volume between the supine and the left recumbent positions. A postural change to the left recumbent position does not affect the cardiac blood circulation or ANS activity, though it does decrease HR in healthy young adults. This finding indicates that the lower HR in the left recumbent position is not attributable to the ANS activity.

Successful management of antibody-mediated rejection after cardiac transplantation in a patient supported by a left ventricular assist device for more than 3 years.

Due to donor shortage, patients with refractory heart failure need to be supported on mechanical circulatory support (MCS). Critically, patients undergo several deployments of MCS in stages inevitably requiring blood products transfusion. MCSs per se along with blood products can trigger immune allosensitization. Antibody-mediated rejection (AMR) is associated with significant mortality after heart transplantation. Here, we present the case with high panel-reactive antibody over 95% who developed AMR early after heart transplantation. This life-threatening complication was successfully treated with multi-modal treatment including anti-CD20 antibody, rituximab.

A case of IgG4-related mesenteritis.

IgG4-related disease is a newly recognized fibroinflammatory condition characterized by tumefaction consisting of fibrosis with dense infiltration of IgG4-positive plasma cells; affecting various organs. A case of IgG4-related sclerosing mesenteritis is reported. A 64-year-old man was admitted to our hospital with a suspected tumor of the small intestine. Abdominal computed tomography demonstrated a 6-cm soft tissue mass in the right lower mesentery compressing the jejunum, which also showed accumulation of fluorodeoxyglucose uptake on fluorine-18 fluorodeoxyglucose positron emission tomography. With a preoperative diagnosis of suspected malignant lymphoma with lymphadenopathy in the mesentery, partial small bowel resection was performed. Macroscopically, a hard mass, including several swollen lymph nodes, was detected in the mesentery. Microscopically, marked fibrosis showing partially storiform pattern, obstructive phlebitis, follicular hyperplasia, and abundant infiltration of IgG4-positive plasma cells were detected. IgG4-related mesenteritis was diagnosed histopathologically, but the serum IgG4 level was 81 mg/dl postoperatively. Five months after the surgery, an 11-cm soft tissue mass involving the left ureter appeared. Histological examination of a biopsy specimen from the retroperitoneal mass showed fibrosis with inflammatory infiltration. Although IgG4-related retroperitoneal fibrosis could not be confirmed histologically, the tumor responded well to steroid therapy.

Organ Correlation in IgG4-Related Diseases.

IgG4-related disease (IgG4-RD) is a potentially multiorgan disorder. In this study, clinical and serological features from 132 IgG4-RD patients were compared about organ correlations. Underlying pathologies comprised autoimmune pancreatitis (AIP) in 85 cases, IgG4-related sclerosing cholangitis (IgG4-SC) in 12, IgG4-related sialadenitis (IgG4-SIA) in 56, IgG4-related dacryoadenitis (IgG4-DAC) in 38, IgG4-related lymphadenopathy (IgG4-LYM) in 20, IgG4-related retroperitoneal fibrosis (IgG4-RF) in 19, IgG4-related kidney disease (IgG4-KD) in 6, IgG4-related pseudotumor (IgG4-PT) in 3. Sixty-five patients (49%) had multiple IgG4-RD (two affected organs in 36 patients, three in 19, four in 8, five in 1, and six in 1). Serum IgG4 levels were significantly higher with multiple lesions than with a single lesion (P<0.001). The proportion of association with other IgG4-RD was 42% in AIP, the lowest of all IgG4-RDs. Serum IgG4 level was lower in AIP than in other IgG4-RDs. Frequently associated IgG4-RDs were SIA (25%) and DAC (12%) for AIP; AIP (75%) for IgG4-SC; DAC (57%), AIP (38%) and LYM (27%) for IgG4-SIA; AIP (26%) and LYM (26%) for IgG4-DAC; SIA (75%), DAC (50%) and AIP (45%) for IgG4-LYM; SIA (58%), AIP (42%) and LYM (32%) for IgG4-RF; AIP (100%) and SIA (67%) for IgG4-KID; and DAC (67%) and SIA (67%) for IgG4-PT. Most associated IgG4-RD lesions were diagnosed simultaneously, but IgG4-SIA and IgG4-DAC were sometimes identified before other lesions. About half of IgG4-RD patients had multiple IgG4-RD lesions, and some associations were seen between specific organs.

[A case of MALT lymphoma of the colon, stomach, and small intestine].

An 85-year-old man was diagnosed with mucosa-associated lymphoid tissue (MALT) lymphoma of the colon in 20XX. Although Helicobacter pylori eradication was performed as part of the treatment, it was ineffective. He was followed-up by colonoscopy for 4 years without additional treatment and there was no interval change;however, he was lost to follow-up 6 years after the first visit. Nine years after the initial diagnosis, he presented with new MALT lymphoma lesions in the stomach and small intestine. Genetic analysis showed that a biopsy specimen was positive for API2/MALT1 fusion gene, and IgH rearrangement showed monoclonal banding between colon and stomach. This suggested disseminated monoclonal API2/MALT1-positive MALT lymphoma of the colon, stomach, and small intestine. Careful attention should be paid to the appearance of multiple lesions in MALT lymphoma.

Allergen-specific IgE antibody serologic assays in patients with autoimmune pancreatitis.

OBJECTIVE: To clarify the allergic manifestations in patients with autoimmune pancreatitis (AIP). METHODS: We assessed 67 AIP patients, before they received steroid therapy, for a past history of allergic disease, the peripheral eosinophil count (n=62) and the serum IgE level (n=53). Allergen-specific IgE antibody serologic assays were performed in 15 patients. RESULTS: A positive past history and/or the presence of active allergic disease were found in 24 AIP patients (36%), including 15 patients with acute allergic rhinitis and eight patients with bronchial asthma. Peripheral eosinophilia and elevation of the serum IgE level were detected in 16% (10/62) and 60% (32/53) of the patients, respectively. Allergen-specific IgE antibody serologic assays were positive in 13 patients (87%). There were no differences between the assay-positive and -negative patients regarding the clinical profiles. CONCLUSION: In conclusion, 87% of the 15 AIP patients tested had positive allergen-specific IgE antibody serologic assays. Allergic mechanisms may be related to the occurrence of AIP.

Ulcerative colitis and immunoglobulin G4.

BACKGROUND/AIMS: Ulcerative colitis (UC) is sometimes associated with autoimmune pancreatitis (AIP). Infiltration of immunoglobulin G4 (IgG4)-positive plasma cells is sometimes detected in the colonic mucosa of AIP or UC patients. This study aimed to clarify the relation between UC and IgG4. METHODS: Associations with UC were reviewed in 85 AIP patients. IgG4 immunostaining was performed on biopsy specimens from the colonic mucosa of 14 AIP and 32 UC patients. RESULTS: UC was confirmed in two cases (type 1 AIP, n=1; suspected type 2 AIP, n=1). Abundant infiltration of IgG4-positive plasma cells in the colonic mucosa was detected in the case of suspected type 2 AIP with UC and two cases of type 1 AIP without colitis. Abundant infiltration of IgG4-positive plasma cells was detected in 10 UC cases (IgG4-present, 31%). Although 72% of IgG4-absent UC patients showed mild disease activity, 70% of IgG4-present patients showed moderate to severe disease activity (p<0.05). CONCLUSIONS: UC is sometimes associated with AIP, but it seems that UC is not a manifestation of IgG4-related disease. Infiltration of IgG4-positive plasma cells is sometimes detectable in the colonic mucosa of UC patients and is associated with disease activity.

Capability and limitations of recent diagnostic criteria for autoimmune pancreatitis.

Because a diagnostic serological marker is unavailable, autoimmune pancreatitis (AIP) is diagnosed based on unique features. The diagnostic capabilities and potential limitations of four sets of diagnostic criteria for AIP (Japanese diagnostic criteria 2006 and 2011, Asian diagnostic criteria, and international consensus diagnostic criteria (ICDC)) were compared among 85 patients who were diagnosed AIP according to at least one of the four sets. AIP was diagnosed in 87%, 95%, 95%, and 95% of the patients according to the Japanese 2006, Asian, ICDC, and Japanese 2011 criteria, respectively. The ICDC can diagnose types 1 and 2 AIP independently and show high sensitivity for diagnosis of AIP. However, as the ICDC are rather complex, diagnostic criteria for AIP should perhaps be revised and tailored to each country based on the ICDC.

Intraductal papillary mucinous neoplasm of the pancreas and IgG4-related disease: a coincidental association.

BACKGROUND/AIMS: Coexistence of autoimmune pancreatitis (AIP) and pancreatic cancer, elevation of serum IgG4 levels in pancreatic cancer patients, and infiltration of IgG4-positive plasma cells in peritumorous pancreatitis have been described in a few reports. This study examined the relationship between intraductal papillary mucinous neoplasm (IPMN) of the pancreas and peritumorous IgG4-positive lymphoplasmacytic infiltrates. METHODS: Serum IgG4 levels were measured in 54 patients with IPMN (median 70 years, 26 males and 28 females; 13 main duct type and 41 branch duct type). Histological findings focusing on dense lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis were reviewed, and immunostaining with IgG4 and IgG was performed in 23 surgically resected IPMN cases (18 main duct type and 5 branch duct type). The presence of IgG4-positive plasma cells >10/hpf and an IgG4-positive/IgG-positive plasma cell ratio >40% were considered significant. RESULTS: Serum IgG4 levels were elevated in 2 (4%) IPMN patients. Significant infiltration of IgG4-positive plasma cells was detected in 4 IPMN cases (17%). The IgG4-positive/IgG-positive plasma cell ratio was >40% in all 4 cases. In one case with a markedly elevated serum IgG4 level (624 mg/dL), typical lymphoplasmacytic sclerosing pancreatitis (AIP type 1) lesions surrounded the whole IPMN. In the 3 other cases, infiltration of IgG4-positive plasma cells with fibrosis was focally detected mainly in the periductal area around the IPMN. CONCLUSIONS: In a few patients with IPMNs, IgG4-positive plasma cell infiltration can occur in the peritumorous area. The association of an IPMN with AIP type 1-like changes seems to be exceptional and coincidental.

Clinical features of 10 patients with IgG4-related retroperitoneal fibrosis.

OBJECTIVE: To elucidate the clinical characteristics of IgG4-related retroperitoneal fibrosis (RF). METHODS: IgG4-related RF was diagnosed when all of the following three criteria were fulfilled: retroperitoneal soft tissue masses surrounding the aorta and/or adjacent tissues, elevation of the serum IgG4 levels, and abundant infiltration of IgG4-positive plasma cells in at least one organ or site. Ten patients were diagnosed as having IgG4-related RF. RESULTS: The mean age at diagnosis was 70.1 years, and the male-to-female ratio was 1:0.6. Only two patients had initial symptoms predominantly related to RF (back pain and edema of the lower extremities), while the remaining eight patients reported initial symptoms due to associated diseases. On laboratory examination, a severe inflammatory reaction was observed in one patient. Elevation of the levels of serum IgG and IgE, eosinophilia and positivity of antinuclear antibodies were detected in seven, five, two and seven patients, respectively. The retroperitoneal masses were detected primarily in the left renal hilus in four patients, in the periaortic region in five patients and in both regions in one patient. Hydronephrosis was present in five patients. The histological diagnosis was confirmed in the retroperitoneal masses (resection, n=1 biopsy, n=2) and extraretroperitoneal lesions (n=7). Twenty-four other IgG4-related diseases were found to be associated with IgG4-related RF in nine patients (autoimmune pancreatitis (n=2), sialadenitis (n=4), dacryoadenitis (n=5), lymphadenopathy (n=9), pulmonary pseudotumor (n=1) and pituitary pseudotumor (n=1)). Seven patients underwent steroid therapy, all of whom responded well and showed no instances relapse. CONCLUSION: IgG4-related RF has several clinical characteristic features. Our diagnostic criteria may be helpful in obtaining a correct diagnosis.