Pancreaticobiliary maljunction and biliary cancer

Pancreaticobiliary maljunction (PBM) is a congenital malformation in which the pancreatic and bile ducts join anatomically outside the duodenal wall. Japanese clinical practice guidelines on how to deal with PBM were made in 2012, representing a world first. According to the 2013 revision to the diagnostic criteria for PBM, in addition to direct cholangiography, diagnosis can be made by magnetic resonance cholangiopancreatography (MRCP), 3-dimensional drip infusion cholangiography computed tomography, endoscopic ultrasonography (US), or multiplanar reconstruction images by multidetector row computed tomography. In PBM, the common channel is so long that sphincter action does not affect the pancreaticobiliary junction, and pancreatic juice frequently refluxes into the biliary tract. Persistence of refluxed pancreatic juice injures epithelium of the biliary tract and promotes cancer development, resulting in higher rates of carcinogenesis in the biliary tract. In a nationwide survey, biliary cancer was detected in 21.6% of adult patients with congenital biliary dilatation (bile duct cancer, 32.1% vs. gallbladder cancer, 62.3%) and in 42.4% of PBM patients without biliary dilatation (bile duct cancer, 7.3% vs. gallbladder cancer, 88.1%). Pathophysiological conditions due to pancreatobiliary reflux occur in patients with high confluence of pancreaticobiliary ducts, a common channel ≥6 mm long, and occlusion of communication during contraction of the sphincter. Once the diagnosis of PBM is established, immediate prophylactic surgery is recommended. However, the surgical strategy for PBM without biliary dilatation remains controversial. To detect PBM without biliary dilatation early, MRCP is recommended for patients showing gallbladder wall thickening on screening US under suspicion of PBM.

Clusterin produced by Sertoli cells inhibits heat stress-induced apoptosis in the rat testis

The objectives of this study were to determine whether the inhibition of clusterin expression in rat Sertoli cells enhances heat stress-induced apoptosis. The scrotums of rats were immersed in a water bath of 43 °C for 15 min. Testicular weight and germ cell number markedly decreased after the heat treatment in a time-dependent manner. In contrast, clusterin mRNA and protein expression levels were significantly up-regulated and peaked on day 21. The apoptotic index was markedly increased 1 day after the heat treatment. We then purified Sertoli cells from the rat testes, and an expression vector containing siRNA targeting the clusterin gene was transiently transfected into Sertoli cells. Following exposure to heat stress at 41 °C for 12 h, clusterin mRNA was markedly up-regulated after transfection with the control vector; however, the transfection of siRNA targeting the clusterin resulted in >70% reduction in the expression of clusterin mRNA. Furthermore, the apoptotic index in these Sertoli cells was significantly higher after the treatment with siRNA targeting the clusterin than control, and the most prominent difference was observed within 24 h after the heat treatment. These results suggest that an increase in the secretion of clusterin by Sertoli cells protects the testes from heat stress-induced injury.

Inhibitory Effect of Acylphloroglucinol Derivatives on the Replication of Vesicular Stomatitis Virus

The antiviral activity of natural phloroglucinols and of synthesized mono- and diacylphloroglucinols, and 2,6-diacyl-4,4-dialkylcyclohexa-1,3,5-triones was investigated. A correlation between the acyl chain length and inhibitory activity against vesicular stomatitis virus (VSV) was observed. Potent antiviral activity was found in di-isovalerylphoroglucinol. 2,6-Diacyl-4,4-dialkylcyclohexa-1,3,5-triones inhibited replication of the virus with low cytotoxicity.

PRPF8 defects cause missplicing in myeloid malignancies

Mutations of spliceosome components are common in myeloid neoplasms. One of the affected genes, PRPF8, encodes the most evolutionarily conserved spliceosomal protein. We identified either recurrent somatic PRPF8 mutations or hemizygous deletions in 15/447 and 24/450 cases, respectively. 50% of PRPF8 mutant and del(17p) cases were found in AML and conveyed poor prognosis. PRPF8 defects correlated with increased myeloblasts and ring sideroblasts in cases without SF3B1 mutations. Knockdown of PRPF8 in K562 and CD34+ primary bone marrow cells increased proliferative capacity. Whole RNA deep sequencing of primary cells from patients with PRPF8 abnormalities demonstrated consistent missplicing defects. In yeast models, homologous mutations introduced into Prp8 abrogated a block experimentally produced in the second step of the RNA splicing process suggesting that the mutants have defects in proof-reading functions. In sum, the exploration of clinical and functional consequences suggests that PRPF8 is a novel leukemogenic gene in myeloid neoplasms with a distinct phenotype likely manifested through aberrant splicing.

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.

Landscape of genetic lesions in 944 patients with myelodysplastic syndromes

High-throughput DNA sequencing significantly contributed to diagnosis and prognostication in patients with myelodysplastic syndromes (MDS). We determined the biological and prognostic significance of genetic aberrations in MDS. In total, 944 patients with various MDS subtypes were screened for known/putative mutations/deletions in 104 genes using targeted deep sequencing and array-based genomic hybridization. In total, 845/944 patients (89.5%) harbored at least one mutation (median, 3 per patient; range, 0-12). Forty-seven genes were significantly mutated with TET2, SF3B1, ASXL1, SRSF2, DNMT3A, and RUNX1 mutated in >10% of cases. Many mutations were associated with higher risk groups and/or blast elevation. Survival was investigated in 875 patients. By univariate analysis, 25/48 genes (resulting from 47 genes tested significantly plus PRPF8) affected survival (P<0.05). The status of 14 genes combined with conventional factors revealed a novel prognostic model ('Model-1') separating patients into four risk groups ('low', 'intermediate', 'high', 'very high risk') with 3-year survival of 95.2, 69.3, 32.8, and 5.3% (P<0.001). Subsequently, a 'gene-only model' ('Model-2') was constructed based on 14 genes also yielding four significant risk groups (P<0.001). Both models were reproducible in the validation cohort (n=175 patients; P<0.001 each). Thus, large-scale genetic and molecular profiling of multiple target genes is invaluable for subclassification and prognostication in MDS patients.

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.

Immunoglobulin G4-related gastrointestinal diseases, are they immunoglobulin G4-related diseases?

In immunoglobulin G4 (IgG4)-related disease (RD), organ enlargement or nodular lesions consisting of abundant infiltration of lymphocytes and IgG4-positive plasma cells and fibrosis are seen in various organs. Although infiltration of many IgG4-positive plasma cells is detected in the gastric and colonic mucosa and major duodenal papilla of patients with autoimmune pancreatitis, it cannot be diagnosed as a gastrointestinal lesion involved in IgG4-RD, because none of the following is observed in these lesions: a mass-like formation; dense fibrosis; or obliterative phlebitis. Based on our review of the literature, there appear to be two types of IgG4-related gastrointestinal disease. One is a gastrointestinal lesion showing marked thickening of the wall of the esophagus and stomach, consisting of dense fibrosis with abundant infiltration of IgG4-positive plasma cells, which usually show submucosal spreading. The other is an IgG4-related pseudotumor occurring in gastrointestinal regions such as the stomach, colon, and major duodenal papilla, showing polypoid or mass-like lesions. Most solitary IgG4-related gastrointestinal lesions that are not associated with other IgG4-RD appear to be difficult to diagnose. It is of utmost importance to rule out malignancy. However, these lesions may respond to steroid therapy. To avoid unnecessary resection, IgG4-related gastrointestinal diseases should be considered in the differential diagnosis.

Mixed acinar-endocrine carcinoma of the pancreas treated with S-1

The case of a 63-year-old male with a large mass in the pancreatic tail and multiple liver metastases, diagnosed as acinar cell carcinoma of the pancreas with a few scattered endocrine cells by liver biopsy is presented. The S-1 chemotherapy was effective, and partial response was obtained with decreased levels of serum CA19.9 and NSE. Ten months after starting chemotherapy, the tumor began to grow accompanied by marked elevation of serum NSE levels (266 ng/ml). The patient died of liver failure due to multiple liver metastasis 18 months after the initiation of the S-1 chemotherapy. Histological findings at autopsy were acinar cell carcinoma with an endocrine component of more than 30 %; the final diagnosis was mixed acinar-endocrine carcinoma of the pancreas. This pathological change and clinical course may imply that S-1 was effective against the acinar component but less effective against the neuroendocrine component caused by tumor differentiation.

Embryological aspects in autoimmune pancreatitis, proposal of autoimmune dorsal pancreatitis

OBJECTIVE

We examined the anatomy of the pancreatic duct system in patients with autoimmune pancreatitis (AIP) from the standpoint of embryological pancreatic primordial.

MATERIAL AND METHODS

The pancreatic duct system involved in 83 AIP patients was embryologically divided into both ventral and dorsal pancreatic ducts (VD type), only the dorsal pancreatic duct (D type), or only the ventral pancreatic duct (V type).

RESULTS

The 83 AIP patients were divided into 62 VD type, 20 D type, and 1 V type. Obstructive jaundice was significantly more frequent in VD type (87%) than in D type (0%; p < 0.01), and abdominal pain was more frequent in D type (24%) than in VD type (2%; p < 0.01). Stenosis of the lower bile duct was detected in 98% of VD type and 15% of D type (p < 0.01). In the 67 patients with involvement of the pancreatic head, only the dorsal pancreatic duct was involved with a normal ventral pancreatic duct in four patients (D type). In the four D-type patients, the pancreatic duct system showed complete pancreas divisum (n = 1), incomplete pancreas divisum (n = 2), or normal pancreatic duct system (n = 1). Stenosis of the lower bile duct was seen in three patients, but was mild, resulting in no obstructive jaundice. Three patients reported abdominal pain and one patient developed acute pancreatitis.

CONCLUSIONS

We propose a new entity of "autoimmune dorsal pancreatitis" in which only the dorsal pancreas is involved, and involvement of the lower bile duct and obstructive jaundice is rare.

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.

Differentiating immunoglobulin g4-related sclerosing cholangitis from hilar cholangiocarcinoma

Background/Aims

Few studies have differentiated immunoglobulin G (IgG) 4-related sclerosing cholangitis (IgG4-SC) from hilar cholangiocarcinoma (CC). Thus, we sought to investigate useful features for differentiating IgG4-SC from hilar CC.

Methods

We retrospectively compared clinical, serological, imaging, and histological features of six patients with IgG4-SC and 42 patients with hilar CC.

Results

In patients with hilar CC, obstructive jaundice was more frequent (p<0.01), serum total bilirubin levels were significantly higher (p<0.05), serum CA19-9 levels were significantly higher (p<0.01), and serum duke pancreatic monoclonal antigen type 2 levels were frequently elevated (p<0.05). However, in patients with IgG4-SC, the serum IgG (p<0.05) and IgG4 (p<0.01) levels were significantly higher and frequently elevated. The pancreas was enlarged in all IgG4-SC patients but only in 17% of hilar CC patients (p<0.01). Salivary and/or lacrimal gland swelling was detected in only 50% of IgG4-SC patients (p<0.01). Endoscopic retrograde cholangiography revealed that the hilar or hepatic duct was completely obstructed in 83% of hilar CC patients (p<0.01). Lower bile duct stenosis, apart from hilar bile duct stenosis, was more frequent in IgG4-SC patients (p<0.01). Bile duct wall thickening in areas without stenosis was more frequent in IgG4-SC patients (p<0.01).

Conclusions

An integrated diagnostic approach based on clinical, serological, imaging, and histological findings is necessary to differentiate IgG4-SC from hilar CC.

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.

Recent advances in autoimmune pancreatitis

It is now clear that are two histological types (Type-1 and Type-2) of autoimmune pancreatitis (AIP). The histological pattern of Type-1 AIP, or traditional AIP, is called lymphoplasmacytic sclerosing pancreatitis (LPSP). The histological pattern of Type-2 AIP is characterized by neutrophilic infiltration in the epithelium of the pancreatic duct. In general, Type-2 AIP patients are younger, may not have a male preponderance, and rarely show elevation of serum IgG4 compared with Type-1 AIP patients. Unlike Type-1 AIP patients, Type-2 AIP patients rarely have associated sclerosing diseases, but they are more likely to have acute pancreatitis and ulcerative colitis. Although Type-2 AIP is sometimes observed in the USA and Europe, most AIP cases in Japan and Korea are Type-1. The international consensus diagnostic criteria for AIP comprise 5 cardinal features, and combinations of one or more of these features provide the basis for diagnoses of both Type-1 and Type-2 AIP. Due to the fact that steroid therapy is clinically, morphologically, and serologically effective in AIP patients, it is the standard therapy for AIP. The indications for steroid therapy in AIP include symptoms such as obstructive jaundice and the presence of symptomatic extrapancreatic lesions. Oral prednisolone (0.6 mg/kg/day) is administered for 2-4 weeks and gradually tapered to a maintenance dose of 2.5-5 mg/day over a period of 2-3 months. Maintenance therapy by low-dose prednisolone is usually performed for 1-3 years to prevent relapse of AIP.

Short and long-term outcomes of diabetes mellitus in patients with autoimmune pancreatitis after steroid therapy

BACKGROUND/AIMS

Autoimmune pancreatitis (AIP) is frequently associated with diabetes mellitus (DM). This study evaluated the effect of steroid therapy on the course of DM in AIP.

METHODS

Glucose tolerance was examined in 69 patients with AIP. DM onset was classified as either a simultaneous onset with AIP or an exacerbation of pre-existing DM. Based on the changes in the HbA1c levels and insulin dose, the responses of DM to steroids were classified as improved, no change, or worsened.

RESULTS

Thirty (46%) patients were diagnosed as having DM (simultaneous onset, n=17; pre-existing, n=13). Three months after starting the steroid treatment, the DM improved in 13 (54%) of 24 DM patients. The DM improved in 55%, had no change in 36%, and worsened in 9% of the 11 simultaneous onset DM patients, and it improved in 54%, had no change in 31%, and worsened in 15% of the 13 pre-existing DM patients. At approximately 3 years after starting the steroid treatment, the DM improved in 10 (63%) of 16 patients. The pancreatic exocrine function improved in parallel with the changes in the DM in seven patients.

CONCLUSIONS

Because approximately 60% of DM associated with AIP is responsive to steroids in the short- and long-terms, marked DM associated with AIP appears to be an indication for steroid therapy.

Modic changes in the cervical spine

We conducted a prospective follow-up MRI study of originally asymptomatic healthy subjects to clarify the development of Modic changes in the cervical spine over a ten-year period and to identify related factors. Previously, 497 asymptomatic healthy volunteers with no history of cervical trauma or surgery underwent MRI. Of these, 223 underwent a second MRI at a mean follow-up of 11.6 years (10 to 12.7). These 223 subjects comprised 133 men and 100 women with a mean age at second MRI of 50.5 years (23 to 83). Modic changes were classified as not present and types 1 to 3. Changes in Modic types over time and relationships between Modic changes and progression of degeneration of the disc or clinical symptoms were evaluated. A total of 31 subjects (13.9%) showed Modic changes at follow-up: type 1 in nine, type 2 in 18, type 3 in two, and types 1 and 2 in two. Modic changes at follow-up were significantly associated with numbness or pain in the arm, but not with neck pain or shoulder stiffness. Age (≥ 40 years), gender (male), and pre-existing disc degeneration were significantly associated with newly developed Modic changes.

In the cervical spine over a ten-year period, type 2 Modic changes developed most frequently. Newly developed Modic changes were significantly associated with age, gender, and pre-existing disc degeneration.