Cystic tumors of the liver: on the problems of diagnostic criteria

We report on three cases of cystic neoplasms of the liver with mucinous epithelium. Case 1 showed a low-grade cystic neoplasm with ovarian-like stroma (OS). Case 2 showed a low-grade cystic neoplasm without OS, and case 3 showed a high-grade cystic neoplasm without OS. In all three cases, bile duct communication (BDC) was absent. Currently, pancreatic mucinous cystic neoplasm (MCN) and intraductal papillary mucinous neoplasm of the pancreas (IPMN) are clearly distinguishable. However, MCN of the liver and intraductal papillary neoplasm of the bile duct (IPN-B) are not as easily distinguished. According to the latest WHO classification (2010), these conditions are classed as typical MCN of the liver, MCNs of the liver without OS, or IPN-Bs without BDC. The clinicopathological differences between MCN without OS and IPN-B without BDC are controversial. We present three cases describing these presentations and discuss the difficulties related to the diagnostic criteria used to distinguish between MCN of the liver and IPN-B.     

乳腺粘液囊肿样病变组织病理学及针吸细胞学改变

目的 分析乳腺粘液囊肿样病变的组织病理学及细针吸取（针吸）细胞学特点,寻求在手术前根据针吸细胞学鉴别ＭＬＬ与乳腺粘液腺癌的依据。方法 重新评估７例ＭＬＬ（良性５例,恶性２例）的组织病理学及针吸细胞学材料,并以同期１４例粘液腺癌作对照,比较两种病变在组织学及针吸细胞学上的差异。     

Overview Article: Ultrastructural Features of the Common Epithelial Tumors of the Ovary: Part II

The ultrastructural features of benign and malignant serous, mucinous, and endometrial variants of ovarian carcinoma are presented. Clear cell tumors and Brenner tumors are also discussed.

Where possible, specific electron microscopic features are stressed.     

肾黏液样小管状和梭形细胞癌临床病理分析

目的：探讨肾黏液样小管状和梭形细胞癌(mucinous tubular and spindle cell carcinoma,MTSCC)的临床病理学特征、诊断和鉴别诊断,提高对MTSCC的认识和诊断水平。方法：对2例MTSCC标本进行临床病理分析,并复习相关文献。结果：肿瘤与周围肾组织分界清楚,肿瘤由紧密排列的、小而狭长的小管构成,小管间为淡染的黏液样间质。肿瘤细胞呈立方形和梭形,肿瘤细胞胞质嗜酸性,细胞核圆形或卵圆形,异型性小,核仁不明显,核分裂像少见,在黏液性间质中可见散在淋巴细胞、浆细胞。免疫组织化学显示2例均表达细胞角蛋白(cytokeratin,CK)7,CK18, CK8/18和波形蛋白,Ki-67增殖指数<5%。结论：MTSCC是一种较罕见的低度恶性肿瘤,具有独特的组织学和免疫组织化学特征,明确该肿瘤的形态学特征、诊断和鉴别诊断有重要意义。     

RNF43 is a tumour suppressor gene mutated in mucinous tumours of the ovary

Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under‐described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild‐type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Free Communications

Ovarian-type mucinous tumours occur very rarely in the retroperitoneum. We present a case of primary retroperitoneal mucinous tumour of borderline malignancy in a 58-year-old woman, detected as an incidental finding. The patient presented with acute renal failure, investigation for which revealed a complex pelvic mass initially thought to be in the right adnexa and consistent with an ovarian neoplasm. Surgical findings revealed a 130-mm, right-sided non-communicating retroperitoneal pelvic mass, posterior to the appendix, which was completely resected. Both ovaries were normal. Macroscopically, it was a multi-loculated cystic structure with a smooth external surface containing clear and mucinous fluid. Microscopic examination showed a mucinous tumour of borderline malignancy. The literature contains approximately nine other cases of primary mucinous retroperitoneal tumour of borderline malignancy. These cases have occurred in women aged 36–60 years. Most patients were asymptomatic and the mass was detected as an incidental finding. The patients have been followed up for up to 6 to 18 months and, to date, none have recurred. There are limitations to pre-operative radiological imaging. A definitive diagnosis can only be made after complete surgical excision and histological examination, having excluded retroperitoneal involvement by mucinous tumours from sites such the ovaries, bowel, appendix and pancreas.     

Guanylyl cyclase C is a specific marker for differentiating primary and metastatic ovarian mucinous neoplasms

Aims:  The aim was to assess the value of GCC in distinguishing primary ovarian mucinous neoplasms from metastatic mucinous adenocarcinomas with ovarian involvement. Guanylyl cyclase C (GCC) is a brush border membrane receptor for the endogenous peptides guanylin and uroguanylin, and the homologous diarrhoeagenic bacterial heat-stable enterotoxins that is selectively expressed by epithelial cells from the duodenum to the rectum, but not by normal epithelia of the stomach or oesophagus, or normal extramucosal cells in humans.
Methods and results:  Fifty ovarian tumours: 27 primary ovarian mucinous neoplasms (seven cystadenomas, 10 borderline tumours and 10 cystadenocarcinomas) and 23 metastatic mucinous adenocarcinomas with ovarian involvement [13 colorectal adenocarcinomas, four gastric adenocarcinomas, six appendiceal mucinous tumours (four adenocarcinomas, one with neuroendocrine features, and two appendiceal mucinous cystadenomas)] were studied. For primary ovarian mucinous neoplasms, 25 of 27 were negative for GCC. Twelve of 13 cases of colorectal adenocarcinoma (except for one neuroendocrine adenocarcinoma) were positive for GCC. Three of four appendiceal mucinous adenocarcinomas were positive for GCC in both the primary and metastatic tumours (except for one neuroendocrine adenocarcinoma). Two of two appendiceal mucinous cystadenomas were positive for GCC. Of four cases of gastric adenocarcinoma with ovarian involvement, only one (primary tumour) exhibited focal GCC staining.
Conclusions:  GCC is a useful marker for differentiating between primary and secondary ovarian mucinous neoplasms.     

Mucinous adenocarcinoma of the tail of the pancreas presenting with a choroidal metastasis

AIM: To report a case of mucinous adenocarcinoma of the tail of the pancreas presenting with a solitary choroidal metastasis. ·METHODS: A 57 years old female patient presented with central metamorphosia in the right eye. Fundoscopy showed a solitary pale raised lesion in the central right macula about 6 disc diameters in length. Her past ocular and medical history was unremarkable. A B-scan confirmed a raised solid lesion in the posterior pole within the macula while fluorescein angiography revealed a central lesion with no areas of leakage. ·RESULTS: In view of the history and the clinical findings a FBC, ESR, LFT, Chest X-ray, and abdominal CT were requested .The chest X-ray revealed multiple opaque lesions in both lung fields suggestive of metastatic pulmonary nodules. The CT revealed multiple nodules in the liver and a 3.5cm x 2.6cmlesion in the tail of the pancreas. A CT guided liver biopsy was performed and it revealed moderately differentiated metastatic mucinous adenocarcinoma. Subsequent blood analysis revealed an elevated CA19-9. The primary tumour site was identified as the tail of the pancreas and was decided to instigate palliative treatment. ·CONCLUSION: There are few reports that demonstrate the significance of a solitary choroidal lesion as the initial clinical sign of cancer of the tail of the pancreas. This case highlights the importance of performing detailed abdominal imaging studies in cases where a solid choroidal lesion of unknown origin is identified.     

胰腺导管内乳头状黏液性肿瘤组织DNMT1和HDAC1的表达及意义

目的:观察胰腺导管内乳头状黏液性肿瘤(IPMNs)组织DNA甲基化转移酶1(DNMT1)和组蛋白去乙酰化酶(HDACI)的表达,探讨其可能的临床意义.方法:免疫组织化学SP法检测DNMT1、HDAC1蛋白在48例IPMNs和54例胰腺导管腺癌(PDAC)组织中的表达并进行统计学分析.结果:DNMT和HDAC1阳性表达率在由正常胰腺导管→1PMA,IPMB→IPMC→PDAc的逐级进展过程中均逐渐升高,二者在IPMNs不同亚型中均有阳性表达.结论:DNMT1和HDAC1高表达是胰腺癌的早期事件,二者的表达水平能够反映IPMNs的恶性进展,但不能作为IPMNs的组织分型标志.     

Liver metastasis of a mucinous colonic carcinoma mimicking a haemangioma in T2‐weighted sequences

We report the case of a patient with a single liver metastasis of a mucinous colonic carcinoma that mimics a haemangioma in T2‐weighted sequences. Although a very high T2 signal in non‐cystic lesions is highly specific for the diagnostic of haemangioma, the use of gadolinium‐enhancement MRI is recommended. In patients with a history of neoplasia, the diagnosis of benign liver nodules should be made with caution.