The Influence of Aerial Exposure on Sea Anemones Aulactinia veratra Mucin Genes Expression Using the RNA Sequencing

Mucin genes are the main component of mucus. The sea anemone species, Aulactinia veratra (Phylum Cnidaria) contains different types of mucin genes. In the intertidal zone, A. veratra is found to be exposed to air during the low tide and produces large quantities of mucus as an external covering. The relation between low tide and mucus secretion is still unclear, and what is the role of mucin during arial exposure is not yet investigated. This study hypothesised that the mucin genes in A. veratra would have significantly high expression in response to aerial exposure. Therefore, the aim of current study was to examine and analyses the response of A. veratra mucins in response to an experiment involving three hours of aerial exposure. To achieve this, aim the RNA-sequencing and bioinformatics analyses were used to examine the expression profile of A. veratra mucin genes in response to aerial exposure. The generated results have shown that, Mucin4-like and mucin5B-like were up-regulated in response to the three hours of aerial exposure in A. veratra. This finding shows a significant role of mucin5B-like and mucin4-like genes in response to air stress at low tide. The data generated from this study could be used in conjunction with future mucin gene studies of sea anemones and other cnidarians to compare A. veratra mucin gene expression results across time, and to extend our understanding of mucin stress response in this phylum.

Pathological features and diagnosis of intraductal papillary mucinous neoplasm of the pancreas

Intraductal papillary mucinous neoplasm(IPMN) of the pancreas is a noninvasive epithelial neoplasm of mucinproducing cells arising in the main duct(MD) and/or branch ducts(BD) of the pancreas.Involved ducts are dilated and filled with neoplastic papillae and mucus in variable intensity.IPMN lacks ovarian-type stroma,unlike mucinous cystic neoplasm,and is defined as a grossly visible entity(≥ 5 mm),unlike pancreatic intraepithelial neoplasm.With the use of high-resolution imaging techniques,very small IPMNs are increasingly being identified.Most IPMNs are solitary and located in the pancreatic head,although 20%-40% are multifocal.Macroscopic classification in MD type,BD type and mixed or combined type reflects biological differences with important prognostic and preoperative clinical management implications.Based on cytoarchitectural atypia,IPMN is classified into low-grade,intermediategrade and high-grade dysplasia.Based on histological features and mucin(MUC) immunophenotype,IPMNs are classified into gastric,intestinal,pancreatobiliary and oncocytic types.These different phenotypes can be observed together,with the IPMN classified according to the predominant type.Two pathways have been suggested:gastric phenotype corresponds to less aggressive uncommitted cells(MUC1-,MUC2-,MUC5 AC +,MUC6 +) with the capacity to evolve to intestinal phenotype(intestinal pathway)(MUC1-,MUC2 +,MUC5 AC +,MUC6- or weak +) or pancreatobiliary /oncocytic phenotypes(pyloropancreatic pathway)(MUC1 +,MUC 2-,MUC5 AC +,MUC 6 +) becoming more aggressive.Prognosis of IPMN is excellent but critically worsens when invasive carcinoma arises(about 40% of IPMNs),except in some cases of minimal invasion.The clinical challenge is to establish which IPMNs should be removed because of their higher risk of developing invasive cancer.Once resected,they must be extensively sampled or,much better,submitted in its entirety for microscopic study to completely rule out associated invasive carcinoma.

Diagnosis and treatment of biliary mucinous cystic neoplasms: A single-center experience

Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and prognosis of BMCNs in a large single center. Methods: We analyzed 49 patients with BMCNs confirmed by postoperative pathology at the First Afflliated Hospital, Zhejiang University School of Medicine between January 2007 and December 2021. Results: Among the 49 patients, 37 were female(75.5%), and the average age was 57.04 years. Common symptoms included abdominal discomfort, jaundice and fever, while 22 patients(44.9%) had no symptoms. Serum carbohydrate antigen(CA) 19-9 and CA125 concentrations were elevated in 34.8% and 19.6% of patients, respectively. Forty-eight patients had tumors in the intrahepatic bile ducts and only one had a tumor in the extrahepatic bile duct. Forty-eight patients with noninvasive intrahepatic BMCNs were further analyzed in terms of pathological features: 34(70.8%) had low-grade intraepithelial neoplasms(LGINs), and 14(29.2%) had high-grade intraepithelial neoplasms(HGINs). The potential immunohistochemical markers of BMCNs were cytokeratin(CK) 19, CK7, estrogen receptor and progesterone receptor. Follow-up data for 37 patients with intrahepatic BMCNs were obtained. The median overall survival(OS) of BMCNs was not reached. The longest survival time was 137 months.The 5-and 10-year OS rates were 100% and 85.4%, respectively. The 5-and 10-year recurrence-free survival(RFS) rates were 93.9% and 80.2%, respectively. Conclusions: BMCNs are rare cystic neoplasms that commonly occur in middle-aged females. BMCNs can only be diagnosed and classified by postoperative pathology, as there are no specific clinical presentations, serological indicators or imaging modalities for preoperative diagnosis. Complete surgical resection is necessary for BMCNs, and the postoperative prognosis is favorable.

Establishment of a cholangiocarcinoma risk evaluation model based on mucin expression levels

BACKGROUND Cholangiocarcinoma(CCA)is a highly malignant cancer,characterized by frequent mucin overexpression.MUC1 has been identified as a critical oncogene in the progression of CCA.However,the comprehensive understanding of how the mucin family influences CCA progression and prognosis is still incomplete.AIM To investigate the functions of mucins on the progression of CCA and to establish a risk evaluation formula for stratifying CCA patients.METHODS Single-cell RNA sequencing data from 14 CCA samples were employed for elucidating the roles of mucins,complemented by bioinformatic analyses.Subse-quent validations were conducted through spatial transcriptomics and immuno-histochemistry.The construction of a risk evaluation model utilized the least absolute shrinkage and selection operator regression algorithm,which was further confirmed by independent cohorts and diverse data types.RESULTS CCA tumor cells with elevated levels of MUC1 and MUC4 showed activated nucleotide metabolic pathways and increased invasiveness.MUC5AC-high cells were found to promote CCA progression through WNT signaling.MUC5B-high cells exhibited robust cellular oxidation activities,leading to resistance against antitumoral treatments.MUC13-high cells were observed to secret chemokines,recruiting and transforming macrophages into the M2-polarized state,thereby suppressing antitumor immunity.MUC16-high cells were found to promote tumor progression through interleukin-1/nuclear factor kappa-light-chain-enhancer of activated B cells signaling upon interaction with neutrophils.Utilizing the expression levels of these mucins,a risk factor evaluation formula for CCA was developed and validated across multiple cohorts.CCA samples with higher risk factors exhibited stronger metastatic potential,chemotherapy resistance,and poorer prognosis.CONCLUSION Our study elucidates the functional mechanisms through which mucins contribute to CCA development,and provides tools for risk stratification in CCA.

Asymptomatic low-grade appendiceal mucinous neoplasm:A case report

BACKGROUND Low-grade appendiceal neoplasms(LAMN)are characterized by low incidence and atypical clinical presentations,often leading to misdiagnosis as acute or chronic appendicitis before surgery.The primary diagnostic tool for LAMN is abdominal computed tomography(CT)imaging.Surgical resection remains the cornerstone of LAMN management,necessitating en bloc tumor excision to minimize the risk of iatrogenic rupture.Laparoscopy,known for its minimal invasiveness,reduced postoperative discomfort,and expedited recovery,is a safe and reliable approach for LAMN treatment.Despite the possibility of pseudomyxoma peritonei development,appendectomy and partial appendectomy generally result in negative tumor margins and favorable outcomes,which can be attributed to the disease’s slow growth and lower malignancy.CASE SUMMARY A 71-year-old male patient was admitted to our hospital with a pelvic spaceoccupying lesion detected 1 mo prior.Physical examination showed a soft abdomen without tenderness or rebound and no palpable masses.No shifting dullness was noted,and digital rectal examination revealed no palpable mass.Enteroscopy revealed a raised,smooth-surfaced mass measuring 3.0 cm in the cecum.Abdominal contrast-enhanced CT showed a markedly thickened and dilated appendix with visible cystic shadows.Laparoscopic surgery was performed and revealed a significantly dilated appendix,leading to laparoscopic resection of the appendix and part of the cecum.Post-surgical pathologic analysis confirmed LAMN.The patient received symptomatic and supportive post-operative care and was discharged on postoperative day 4 without complications such as abdominal bleeding,intestinal obstruction,or incision infection.No tumor recurrence was observed during a 7-mo follow-up period.CONCLUSION LAMN is a rare disease that lacks specific clinical manifestations.Abdominal CT plays a crucial role in diagnosing LAMN,and laparoscopic surgery is a safe and effective diagnostic and therapeutic approach.

Waist subcutaneous soft tissue metastasis of rectal mucinous adenocarcinoma: A case report

BACKGROUND Rectal mucinous adenocarcinoma(MAC)is a rare pathological type of rectal can-cer with unique pathological features and a poor prognosis.It is difficult to diag-nose and treat early because of the lack of specific manifestations in some aspects of the disease.The common metastatic organs of rectal cancer are the liver and lung;however,rectal carcinoma with metastasis to subcutaneous soft tissue is a rare finding.CASE SUMMARY In this report,the clinical data,diagnosis and treatment process,and postope-rative pathological features of a patient with left waist subcutaneous soft tissue masses were retrospectively analyzed.The patient underwent surgical treatment after admission and recovered well after surgery.The final pathological diagnosis was rectal MAC with left waist subcutaneous soft tissue metastasis.CONCLUSION Subcutaneous soft tissue metastasis of rectal MAC is rare,and it can suggest that the tumor is disseminated,and it can appear even earlier than the primary ma-lignant tumor,which is occult and leads to a missed diagnosis and misdiagnosis clinically.When a subcutaneous soft tissue mass of unknown origin appears in a patient with rectal cancer,a ma-lignant tumor should be considered.

Mucinous neoplasm of the appendix:A case report and review of literature

BACKGROUND Appendiceal mucinous neoplasms(AMNs),although not classified as rare,are relatively uncommon tumors most often discovered incidentally during colorectal surgery.Accurate identification of AMNs is difficult due to non-specific sym-ptoms,overlapping tumor markers with other conditions,and the potential for misdiagnosis.This underscores the urgent need for precision in diagnosis to pre-vent severe complications.CASE SUMMARY This case report describes the unexpected discovery and treatment of a low-grade AMN(LAMN)in a 74-year-old man undergoing laparoscopic hemicolectomy for transverse colon adenocarcinoma(AC).Preoperatively,non-specific gastroin-testinal symptoms and elevated tumor markers masked the presence of AMN.The tumor,presumed to be an AMN peritoneal cyst intraoperatively,was con-firmed as LAMN through histopathological examination.The neoplasm exhibited mucin accumulation and a distinct immunohistochemical profile:Positive for Ho-meobox protein CDX-2,Cytokeratin 20,special AT-rich sequence-binding protein 2,and Mucin 2 but negative for cytokeratin 7 and Paired box gene 8.This profile aids in distinguishing appendiceal and ovarian mucinous tumors.Postoperative recovery was uncomplicated,and the patient initiated adjuvant chemotherapy for the colon AC.CONCLUSION This case highlights the diagnostic complexity of AMNs,emphasizing the need for vigilant identification to avert potential complications,such as pseudomyxoma peritonei.

Advances in the Diagnosis and Treatment of Appendiceal Mucinous Neoplasms

Primary appendiceal neoplasms represent a relatively low percentage of all gastrointestinal cancers. A subset of these neoplasms, those of epithelial origin, are characterised by the production of a considerable amount of mucus, which is referred to as appendiceal mucinous neoplasms (AMN). Appendiceal mucinous neoplasms (AMN) have a low incidence, are easily misdiagnosed, depend on postoperative examination for confirmation of the diagnosis, are prone to form a “diagnosis”, and have a high incidence of the disease. Furthermore, they are prone to form peritoneal pseudomyxoma peritonei (PMP), are controversial in surgical decision-making, are prone to recurring after surgery alone, and are tricky to manage clinically. In this paper, we review the pathological characteristics, diagnosis and treatment of appendiceal mucinous tumours in the light of recent literature reports, with a view to providing certain references for the clinical diagnosis and treatment of this disease. .

Validation of serum tumor biomarkers in predicting advanced cystic mucinous neoplasm of the pancreas

BACKGROUND Early detection of advanced cystic mucinous neoplasms[(A-cMNs),defined as high-grade dysplasia or malignancy]of the pancreas is of great significance.As a simple and feasible detection method,serum tumor markers(STMs)may be used to predict advanced intraductal papillary mucinous neoplasms(IPMNs)and mucinous cystic neoplasms(MCNs).However,there are few studies on the usefulness of STMs other than carbohydrate antigen(CA)19-9 for early detection of A-cMNs.AIM To study the ability of five STMs-CA19-9,carcinoembryonic antigen(CEA),CA125,CA724,and CA242 to predict A-cMNs and distinguish IPMNs and MCNs.METHODS We mainly measured the levels of each STM in patients pathologically diagnosed with cMNs.The mean levels of STMs and the number of A-cMN subjects with a higher STM level than the cutoff were compared respectively to identify the ability of STMs to predict A-cMNs and distinguish MCNs from IPMNs.A receiver operating characteristic curve with the area under curve(AUC)was also created to identify the performance of the five STMs.RESULTS A total of 187 patients with cMNs were identified and 72 of them showed AcMNs.We found that CA19-9 exhibited the highest sensitivity(SE)(54.2%)and accuracy(76.5%)and a moderate ability(AUC=0.766)to predict A-cMNs.In predicting high-grade dysplasia IPMNs,the SE of CA19-9 decreased to 38.5%.The ability of CEA,CA125,and CA724 to predict A-cMNs was low(AUC=0.651,0.583,and 0.618,respectively).The predictive ability of CA242 was not identified.The combination of STMs improved the SE to 62.5%.CA125 may be specific to the diagnosis of advanced MCNs.CONCLUSION CA19-9 has a moderate ability,and CEA,CA125,and CA724 have a low ability to predict A-cMNs.The combination of STM testing could improve SE in predicting A-cMNs.

Solitary acral persistent papular mucinosis nodule:A case report and summary of eight Korean cases

BACKGROUND Acral persistent papular mucinosis(APPM)is a rare idiopathic subtype of localized lichen myxedematosus.To date,there have been 40 APPM cases reported worldwide;however,only 7 cases have been reported in the Korean literature.CASE SUMMARY A 70-year-old man was referred to our hospital with a solitary pinkish nodule on the dorsum of his right hand.Despite the absence of symptoms,the patient wanted to know the exact diagnosis;thus,a biopsy was performed.Histopathological examination of a biopsy specimen obtained from the nodule on the dorsum of his hand revealed orthokeratotic hyperkeratosis with patchy parakeratosis,prominent hypergranulosis,and diffuse dissecting mucinous deposition between collagen bundles,along with some bland-looking spindle cells throughout the dermis.The nodule was histologically diagnosed as an APPM,and an intralesional triamcinolone injection(2.5 mg/mL)was started every 2 wk.After three sessions of treatment,the patient showed marked improvements.CONCLUSION To the best of our knowledge,this is the first case of a Korean APPM presenting as a solitary nodule that showed a marked response to triamcinolone intralesional injection.Since it is a rare disease,we report this case to contribute to future research on the pathogenesis and treatment of APPM.

RET、Mucin1和Galectin-3在甲状腺良恶性肿瘤中的表达

目的 :探讨滤泡源性甲状腺肿瘤及结节性甲状腺肿中RET、Mucin 1和Galectin 3蛋白的表达 ,寻找有助于诊断良恶性甲状腺肿瘤的标志物。 方法 :采用免疫组化S P法 ,检测 19例结节性甲状腺肿 ,5 4例腺瘤 (其中不典型腺瘤 19例 ) ,4 3例乳头状癌 (其中 11例乳头状微癌 ) ,16例滤泡性癌中上述 3种蛋白的表达情况。 结果 :良性病变 (结节性甲状腺肿和腺瘤 )与恶性病变 (乳头状癌和滤泡性癌 )中 3种蛋白的表达差异有极显著意义 (P <0 .0 1) ,而良恶性病变中的不同类型间的差异无显著性 (P >0 .0 5 )。 11例微癌患者中Galectin 3全部阳性 ,RET 8例阳性 ,Mucin 1阳性仅 3例 ;结节性甲状腺肿RET的表达与甲状腺癌比较虽无统计学意义 (P >0 .0 5 ) ,但前者为弱阳性 ,后者多为强阳性 ;腺瘤中不典型腺瘤Galectin 3的表达与其他腺瘤相比差异显著 (P <0 .0 5 ) ,与滤泡性癌相比差异无显著意义 (P >0 .0 5 ) ;部分腺瘤中见灶性Mucin 1和Galectin 3同时阳性。结论 :RET、Mucin 1和Galectin 3的同时检测可作为良恶性滤泡上皮性肿瘤鉴别诊断的指标 ,其中以Galectin 3的敏感性最佳 ,RET次之。Mucin 1高表达可能是去分化、浸润和转移的标志 ,Galectin 3阳性的不典型腺瘤是滤泡性腺瘤和滤泡性癌的交界性病变 ,良性腺瘤中Mucin 1?

胃肠道黏液层中Akkermansia muciniphila的定殖及其与宿主的相互作用

动物胃肠道中定殖着数量巨大的肠道微生物,影响宿主动物的代谢和发育。肠道微生物在营养物质交换、信息传递和抵抗病原微生物入侵方面均发挥着重要的作用。依据定殖部位,可以分成黏液层微生物和肠腔内微生物,Akkermansia muciniphila偏好地定殖于肠道黏液层,对机体活动影响广泛。在肠道中,Akkermansia muciniphila可以特异地降解黏蛋白和低聚糖,分别产生短链脂肪酸和丙酸,在为宿主提供能量的同时也促进了自身的定殖。而与此同时,机体黏蛋白的降解会促使宿主补偿产生更多的黏蛋白,进而降低宿主蛋白的沉积。Akkermansia muciniphila的定殖还可减缓脂肪沉积,延缓糖尿病。在肠道微生态系统中,该菌群并没有严重的致病性,适宜丰度的Akkermansia muciniphila定殖可以促进宿主免疫系统的发育,进而促进肠道健康。随着更多科学研究的展开,胃肠道微生物在机体中的重要性得到呈现。作为目前国内外的研究热点,Akkermansia muciniphila在机体肠道内的作用机制尚未完全明确。本文从Akkermansia muciniphila的定殖环境、生理特性、对机体营养代谢的影响、与代谢性疾病及机体免疫相互作用等方面进行了综述,Akkermansia muciniphila为很有潜力的生物标记,应用于营养状态、代谢性疾病、免疫甚至癌症的评估和检测。

Management of mucinous cystic neoplasms of the pancreas

The purpose of this study was to investigate the actual management of mucinous cystic neoplasm (MCN) of the pancreas. A systematic review was performed in December 2009 by consulting PubMed MEDLINE for publications and matching the "pancreatic mucinous cystic neoplasm", "pancreatic mucinous cystic tumour", "pancreatic mucinous cystic mass", "pancreatic cyst", and "pancreatic cystic neoplasm" to identify English language articles describing the diagnosis and treatment of the mucinous cystic neoplasm of the pancreas. In total, 16 322 references ranging from January 1969 to December 2009 were analysed and 77 articles were identified. No articles published before 1996 were selected because MCNs were not previously considered to be a completely autonomous disease. Definition, epidemiology, anatomopathological findings, clinical presentation, preoperative evaluation, treatment and prognosis were reviewed. MCNs are pancreatic mucinproducing cysts with a distinctive ovarian-type stroma localized in the body-tail of the gland and occurring in middle-aged females. The majority of MCNs are slow growing and asymptomatic. The prevalence of invasive carcinoma varies between 6% and 55%. Preoperative diagnosis depends on a combination of clinical features, tumor markers, computed tomography (CT), magnetic resonance imaging, endoscopic ultrasound with cyst fluid analysis, and positron emission tomography-CT. Surgery is indicated for all MCNs.

Clinical diagnosis and management of pancreatic mucinous cystadenoma and cystadenocarcinoma:Single-center experience with 82 patients

BACKGROUND Mucinous cystic neoplasm(MCN)of the pancreas is characterized by mucinproducing columnar epithelium and dense ovarian-type stroma and at risk for malignant transformation.Early diagnosis and treatment of MCN are particularly important.AIM To investigate the clinical characteristics of and management strategies for pancreatic mucinous cystadenoma(MCA)and mucinous cystadenocarcinoma(MCC).METHODS The clinical and pathological data of 82 patients with pancreatic MCA and MCC who underwent surgical resection at our department between April 2015 and March 2019 were retrospectively analyzed.RESULTS Of the 82 patients included in this study,70 had MCA and 12 had MCC.Tumor size of MCC was larger than that of MCA(P=0.049).Age and serum levels of tumor markers carcinoembryonic antigen(CEA),carbohydrate antigen(CA)19-9,and CA12-5 were significantly higher in MCC than in MCA patients(P=0.005,0.026,and 0.037,respectively).MCA tumor size was positively correlated with serum CA19-9 levels(r=0.389,P=0.001).Compared with MCC,MCA had a higher minimally invasive surgery rate(P=0.014).In the MCA group,the rate of major complications was 5.7%and that of clinically relevant pancreatic fistula was 8.6%;the corresponding rates in the MCC group were 16.7%and 16.7%,respectively.CONCLUSION Tumor size,age,and serum CEA,CA19-9,and CA12-5 levels may contribute to management of patients with MCN.Surgical resection is the primary treatment modality for MCC and MCA.

Effect of mucin production on survival in colorectal cancer:A case-control study

AIM： TO investigate the impact of mucin production on prognosis in colorectal cancer, in terms of overall survival （OS） and time to disease progression （TTP） in patients with mucinous compared to those with nonmucinous colorectal cancer （NMCRC）, matched for age, gender, and tumor stage. METHODS： Thirty five patients with mucinous colorectal cancer （MCRC） were matched for age, gender, and tumor stage with 35 controls having NMCRC. OS and TTP were compared among 4 groups divided according to mucin content： group A （50%-75% mucin）, group B （75%-100% mucin）, group C or controls （〈 50% mucin）. Group D consisted of all patients with tumors having 〈 75% mucin （controls and groups A together）. RESULTS： Median survival in MCRC and NMCRC groups was 46.2 and 112.9 mo, respectively （P = 0.26）. OS in groups A and B was 70.1 and 32.8 mo （P = 0.46）, and in groups B and D was 32.8 and 70.1 mo, respectively （P = 0.143）. TTP in MCRC and NMCRC was 50.17 and 44.77 too, respectively （P = 0.795）. TTP in groups A, B, and D was 70.1, 24.8, and 65.5 too, respectively. Twenty-eight percent of patients with MCRC had poorly differentiated adenocarcinoma versus 8.6% in NMCRC patients （P = 0.028）. CONCLUSION： MCRC is associated with a non-significant decrease in median survival and TTP, particularly when mucin content is 〉 75% of tumor volume. However, it tends to be more poorly differentiated. A larger study matching for stage and grade is needed.

Intraductal papillary mucinous neoplasms and other pancreatic cystic lesions

Pancreatic cystic neoplasms are being increasingly recognized, even in the absence of symptoms, in large part, due to markedly improved imaging modalities such as magnetic resonance imaging (MRI)/magnetic resonance cholangio pancreatography (MRCP) and computer tomography (CT) scanning. During the past 2 decades, better imaging of these cystic lesions has resulted in definition of different types, including pancreatic intraductal papillary mucinous neoplasms (IPMN). While IPMN represent only a distinct minority of all pancreatic cancers, they appear to be a relatively frequent neoplastic form of pancreatic cystic neoplasm. Moreover, IPMN have a much better outcome and prognosis compared to pancreatic ductal adenocarcinomas. Therefore, recognition of this entity is exceedingly important for the clinician involved in diagnosis and further evaluation of a potentially curable form of pancreatic cancer.

Mucinous adenocarcinoma:A unique clinicopathological subtype in colorectal cancer

Mucinous adenocarcinoma(MAC)is a unique clinicopathological subtype of colorectal cancer,which is characterized by extracellular mucinous components that comprise at least 50%of the tumor tissue.The clinical characteristics,molecular features,response to chemo-/radiotherapy,and prognosis of MAC are different from that of non-MAC(NMAC).MAC is more common in the proximal colon,with larger volume,higher T-stage,a higher proportion of positive lymph nodes,poorer tumor differentiation,and a higher proportion of peritoneal implants compared to NMAC.Although biopsy is the main diagnostic method for MAC,magnetic resonance imaging is superior in accuracy,especially for rectal carcinoma.The aberrant expression of mucins,including MUC1,MUC2 and MUC5AC,is a notable feature of MAC,which may be related to tumor invasion,metastasis,inhibition of apoptosis,and chemo-/radiotherapy resistance.The genetic origin of MAC is mainly related to BRAF mutation,microsatellite instability,and the CpG island methylator phenotype pathway.In addition,the poor prognosis of rectal MAC has been confirmed by various studies,and that of colonic MAC is still controversial.In this review,we summarize the epidemiology,clinicopathological characteristics,molecular features,methods of diagnosis,and treatments of MAC in order to provide references for further fundamental and clinical research.

Intraductal papillary mucinous carcinoma with atypical manifestations:Report of two cases

Intraductal papillary mucinous neoplasms （IPMNs） are a well-characterized group of rnucin-producing cystic neoplasms of the clear malignant potential type. We report here two cases of intraductal papillary mucinous carcinoma （IPMC） with atypical manifestations. In one case, we discussed a pseudomyxoma peritonei caused by a ruptured IPMC. In the other case we discussed the fistulization of IPMC into the stomach and duodenum. These two cases suggest that IPMN can either spontaneously rupture causing mucinous materials to spill into the free abdominal cavity or directly invade adjacent organs resulting in fistula development.

Multifocal intraductal papillary mucinous neoplasm of the pancreas-A case report

Cystic neoplasms of the pancreas are relatively rare, comprising 10 percent of pancreatic cysts and only 1 percent of pancreatic cancers. Cystic neoplasms include mucinous cystic neoplasms, serous cystadenomas, papillary cystic tumors, cystic islet cell tumors and intraductal papillary mucinous neoplasms of the pancreas (IPMNs). IPMN was first described in 1982. It has been most commonly described in 60 to 70 years old males, and represents a relatively ''new'' but increasingly recognized disease. The improvement and widespread use of modern imaging equipments and heightened awareness of physicians contribute to the increasing incidence of IPMN. The majority of IPMNs are located in the pancreatic head (75%) while the rest involves the body/tail regions. Multifocal IPMNs have been hypothesized, but the true presence of multifocality is unknown. Here we present a 72-yearold male diagnosed with IPMN (carcinoma in situ ) in the pancreatic head and a branch duct type IPMN (duct atypia) in the pancreatic body and tail. The patient underwent a Whipple intervention and a distal pancreatectomy. A three-year disease-free survival has been observed so far.

Mucinous nonneoplastic cyst of the pancreas: A truly novel pathological entity?

Recently, a novel and distinct pancreatic cystic tumor termed 'mudnous nonneoplastic' cyst was described in the literature. We report our experience with a 71-year-old female with a cystic tumor in the body of the pancreas demonstrating features suggestive of this diagnosis. We also review the literature regarding this 'novel' pathological entity and discuss critically its existence and its differential diagnoses.