Inhibition of ß-Catenin Activity Abolishes LKB1 Loss-Driven Pancreatic Cystadenoma in Mice.

Pancreatic cancer (PC) is the seventh leading cause of cancer death worldwide, and remains one of our most recalcitrant and dismal diseases. In contrast to many other malignancies, there has not been a significant improvement in patient survival over the past decade. Despite advances in our understanding of the genetic alterations associated with this disease, an incomplete understanding of the underlying biology and lack of suitable animal models have hampered efforts to develop more effective therapies. LKB1 is a tumor suppressor that functions as a primary upstream kinase of adenine monophosphate-activated protein kinase (AMPK), which is an important mediator in the regulation of cell growth and epithelial polarity pathways. LKB1 is mutated in a significant number of Peutz-Jeghers syndrome (PJS) patients and in a small proportion of sporadic cancers, including PC; however, little is known about how LKB1 loss contributes to PC development. Here, we report that a reduction in Wnt/ß-catenin activity is associated with LKB1 tumor-suppressive properties in PC. Remarkably, in vivo functional analyses of ß-catenin in the Pdx-1-Cre LKB1L/L ß-cateninL/L mouse model compared to LKB1 loss-driven cystadenoma demonstrate that the loss of ß-catenin impairs cystadenoma development in the pancreas of Pdx-1Cre LKB1L/L mice and dramatically restores the normal development and functions of the pancreas. This study further determined the in vivo and in vitro therapeutic efficacy of the ß-catenin inhibitor FH535 in suppressing LKB1 loss-driven cystadenoma and reducing PC progression that delineates the potential roles of Wnt/ß-catenin signaling in PC harboring LKB1 deficiency.

Simple mucinous cyst: another potential cancer precursor in the pancreas? Case report with molecular characterization and systematic review of the literature.

Cystic lesions of the pancreas may range from benign to precursors of pancreatic cancer. Simple mucinous cyst (SMC) is larger than 1 cm, has a gastric-type flat mucinous lining, and minimal atypia without ovarian-type stroma. We report a new case of pancreatic SMC, coupling a systematic review of the English literature mainly focused on their clinic-pathological features. We reviewed 103 cases of SMC in adults (73 women), averaging 57 (range, 26-70) years. The SMCs were located in the body-tail region of the pancreas in 60 (58%) cases, presenting as single cystic lesions in 94% of cases; 43% of patients were asymptomatic. A preoperative fine-needle aspiration of the cyst fluid detected amylase and carcinoembryonic antigen positivity in 71% and 76% of cases, respectively. Patients underwent surgery mostly for suspected malignancy; in 83% of cases, a standard pancreatic resection was performed. Mean SMC size was 4.9 (range, 1.5-12.0) cm. Mucins MUC5AC and MUC6 resulted positive in 77% and 81% of cases performed, respectively, whereas MUC2 was negative in all but one patient. The SMC from our institution was characterized by a KRAS somatic mutation. The diagnosis of SMC should be considered when a solitary pancreatic cyst larger than 1 cm is detected in asymptomatic patients. To establish a correct diagnosis, an extensive histologic/immunohistochemical analysis is essential. The presence of a KRAS mutation highlights that SMC may represent another potential pancreatic cancer precursor.

The utility of PAX8 and SATB2 immunohistochemical stains in distinguishing ovarian mucinous neoplasms from colonic and appendiceal mucinous neoplasm.

OBJECTIVES: It is challenging to distinguish between primary ovarian mucinous tumors and metastatic mucinous neoplasms from the lower gastrointestinal tract, including appendiceal tumors. A combination of PAX8 and SATB2 immunohistochemical stains can be used as a diagnostic tool to distinguish between these cases. RESULTS: Immunostaining for SATB2, PAX8, CK7, CK20 and CDX2 was performed on 50 ovarian mucinous neoplasms (OMN) (39 cystadenomas, 4 borderline and 7 adenocarcinomas), 63 mucinous colorectal carcinoma (CRC), and 9 appendiceal mucinous neoplasms (AMN) [8 low grade appendiceal mucinous neoplasms (LAMN) and 1 adenocarcinoma]. PAX8 was positive in 32% of OMN and negative in all CRC and AMN cases. SATB2 was expressed in 2.0% of OMN, 77.8% of AMN, and 49.2% of CRC cases. CK7 was positive in 78.0% of OMN, 33.3% of AMN, and 9.5% of CRC cases. CK20 was expressed in 24.0% of OMN, 88.9% of OMN, and 87.3% of CRC cases. CDX2 was positive in 14.0% of OMN, 100% of AMN, and 90.5% of CRC cases. PAX8 can differentiate between OMN and AMN with high specificity but low sensitivity. CDX2 is the most sensitive marker for CRC and AMN, whereas SATB2 has better specificity.

Distinct methylation profile of mucinous ovarian carcinoma reveals susceptibility to proteasome inhibitors.

Mucinous type of epithelial ovarian cancer (MuOC) is a unique subtype with a poor survival outcome in recurrent and advanced stages. The role of type-specific epigenomics and its clinical significance remains uncertain. We analyzed the methylomic profiles of 6 benign mucinous adenomas, 24 MuOCs, 103 serous type of epithelial ovarian cancers (SeOCs) and 337 nonepithelial ovarian cancers. MuOC and SeOC exhibited distinct DNA methylation profiles comprising 101 genes, 81 of which exhibited low methylation in MuOC and were associated with the response to glucocorticoid, ATP hydrolysis-coupled proton transport, proteolysis involved in the cellular protein catabolic process and ion transmembrane transport. Hierarchical clustering analysis showed that the profiles of MuOC were similar to colorectal adenocarcinoma and stomach adenocarcinoma. Genetic interaction network analysis of differentially methylated genes in MuOC showed a dominant network module is the proteasome subunit beta (PSMB) family. Combined functional module and methylation analysis identified PSMB8 as a candidate marker for MuOC. Immunohistochemical staining of PSMB8 used to validate in 94 samples of ovarian tumors (mucinous adenoma, MuOC or SeOC) and 62 samples of gastrointestinal cancer. PSMB8 was commonly expressed in MuOC and gastrointestinal cancer samples, predominantly as strong cytoplasmic and occasionally weak nuclei staining, but was not expressed in SeOC samples. Carfilzomib, a second-generation proteasome inhibitor, suppressed MuOC cell growth in vitro. This study unveiled a mucinous-type-specific methylation profile and suggests the potential use of a proteasome inhibitor to treat MuOC.

Prohibitin: targeting peptide coupled to ovarian cancer, luteinization and TGF-ß pathways.

BACKGROUND: Ovarian epithelial tumor (OET) is a silent disease of late diagnosis and poor prognosis. Currently treatment options are limited and patient response to treatment is difficult to predict so there is a serious need to delineate the real pathogenesis to predict tumour prognosis. Prohibitin (PHB) is an evolutionarily protein that regulates the cell cycle. TGF-ß has been shown to be a positive and negative regulator of cellular proliferation and differentiation. The present study provides an overview on the role played by PHB1, TGF-ß and LH in ovarian cancer. METHODS: The study was conducted on 60 patients with ovarian tumors (benign, borderline and malignant) and 20 healthy volunteers. LH and TGF-ß serum levels were measured by ELISA. Expression of prohibitin and LHR-mRNA were assessed by IHC and TaqMan® real time gene expression assay, respectively. RESULTS: Serum levels of LH and TGF-ß were significantly decreased among borderline and malignant groups. There was significant over-expression of LHRmRNA in malignant group. Prohibitin expression was significantly increased in malignant ovarian tissue. Strong negative correlations were found between LHR mRNA expression and serum LH levels, and between IHC score of prohibitin and serum levels of LH among patients with borderline ovarian tumors. CONCLUSION: Steady decline of LH and TGF-B serum levels, from benign cystadenoma to borderline tumor to carcinoma, suggests their inhibitory role against OET cell growth. Increased PHB1 expression in OET suggests its proliferative activity that can be regulated by luteinisation and/or TGF-ß. Furthermore increased LHR mRNA tissue expression can provide hope for using LH in treatment of some types of ovarian cancers.

Suboptimal accuracy of carcinoembryonic antigen in differentiation of mucinous and nonmucinous pancreatic cysts: results of a large multicenter study.

BACKGROUND AND AIMS: The exact cutoff value at which pancreatic cyst fluid carcinoembryonic antigen (CEA) level distinguishes pancreatic mucinous cystic neoplasms (MCNs) from pancreatic nonmucinous cystic neoplasms (NMCNs) is unclear. The aim of this multicenter retrospective study was to evaluate the diagnostic accuracy of cyst fluid CEA levels in differentiating between MCNs and NMCNs. METHODS: Consecutive patients who underwent EUS with FNA at 3 tertiary care centers were identified. Patients with histologic confirmation of cyst type based on surgical specimens served as the criterion standard for this analysis. Demographic characteristics, EUS morphology, FNA fluid, and cytology results were recorded. Multivariate logistic regression analysis to identify predictors of MCNs was performed. Receiver-operating characteristic (ROC) curves were generated for CEA levels. RESULTS: A total of 226 patients underwent surgery (mean age, 61 years, 96% white patients, 39% female patients) of whom 88% underwent Whipple's procedure or distal pancreatectomy. Based on surgical histopathology, there were 150 MCNs and 76 NMCNs cases. The median CEA level was 165 ng/mL. The area under the ROC curve for CEA levels in differentiating between MCNs and NMCNs was 0.77 (95% confidence interval, 0.71-0.84, P < .01) with a cutoff of 105 ng/mL, demonstrating a sensitivity and specificity of 70% and 63%, respectively. The cutoff value of 192 ng/mL yielded a sensitivity of 61% and a specificity of 77% and would misdiagnose 39% of MCN cases. CONCLUSIONS: Cyst fluid CEA levels have a clinically suboptimal accuracy level in differentiating MCNs from NMCNs. Future studies should focus on novel cyst fluid markers to improve risk stratification of pancreatic cystic neoplasms.

Different staining patterns of ovarian Brenner tumor and the associated mucinous tumor.

The association of ovarian Brenner tumors and adjacent mucinous tumors is well known but not completely understood. In this study, we analyzed immunohistochemical markers on Brenner tumors and their associated mucinous tumor to explore Mullerian as well as Wolffian and germ cell derivation and determine if the mucinous component is independent or related to the Brenner tumor. Of 32 consecutive cases of Brenner tumors, 8 were identified with significant mucinous component, and 7 additional cases included foci of mucinous epithelium within the Brenner transitional nests. All Brenner tumors were diffusely positive for GATA3 and negative for Paired box gene 8, PAX2, and Sal-like protein 4. Interestingly, the areas of mucinous epithelium as well as mucinous tumors, intermixed and adjacent to the Brenner tumor, were negative for all 4 markers; however, occasional basal-like cells retained expression of GATA3. The immunoprofile of mucinous tumors associated with Brenner tumors shares the lack of Mullerian markers PAX2 and Paired box gene 8 with the Brenner tumor but differs in the expression of GATA3 only in the Brenner tumor component.

Association of pancreatic adenocarcinoma up-regulated factor expression in ovarian mucinous adenocarcinoma with poor prognosis.

Pancreatic adenocarcinoma up-regulated factor (PAUF) expression is elevated in both ovarian tumors and pancreatic adenocarcinoma. However, PAUF expression in ovarian tumors according to histologic subtype and grade has not been investigated. In this study, we examined various clinicopathologic features of 24 patients with mucinous cystadenoma (MCA), 36 with mucinous borderline tumors (MBTs), and 46 with mucinous adenocarcinomas (MACs) according to PAUF expression status assessed using immunohistochemistry. We found that MACs more frequently stained positive for PAUF than did MCAs and MBTs (P < 0.0001). Although there was no significant differences with respect to other clinicopathologic characteristics of MACs according to PAUF expression status, patients with PAUF-weakly positive and PAUF-strongly positive MACs tended to have a shorter overall survival (OS) than those with PAUF-negative MAC, determined using a Kaplan-Meier analysis (P = 0.1885). After adjusting for various clinicopathologic parameters, PAUF positivity of MACs was a significant predictive factor for disease-free survival (DFS) (negative vs. weakly positive: P = 0.045, hazard ratio [HR] = 57.406, 95% confidence interval [CI]: 1.090-3022.596; and negative vs. strongly positive: P = 0.034, HR = 97.890, 95% CI: 1.412-6785.925). In conclusion, PAUF was more frequently expressed in MAC than in its benign and borderline counterparts, and was associated with a poor OS and DFS in MAC patients. Therefore, we suggest that PAUF may be a practical biomarker for histopathological categorization and a prognostic marker for patients with an ovarian mucinous tumor.

Accuracy of endoscopic ultrasound in the evaluation of cystic pancreatic neoplasms: a community hospital experience.

OBJECTIVES: Reports on the use of endoscopic ultrasound (EUS) in differentiating benign, premalignant, and malignant pancreatic lesions have been widely variable, particularly with cystic neoplasms. We evaluated the use of EUS for cystic pancreatic lesions in a community hospital setting. METHODS: All patients who underwent EUS for cystic pancreatic neoplasms from 2007 to 2010 were reviewed. A final EUS diagnosis was determined based on the examiner's impression and fine-needle aspiration results if available. Lesions were stratified as benign, premalignant, or malignant. Patients underwent surgical resection, serial imaging studies, or medical oncology/palliative care consultation as indicated. RESULTS: One hundred eighteen patients with cystic pancreatic lesions underwent EUS during the study period. Endoscopic ultrasound diagnoses included 75 benign (63.6%), 35 premalignant (29.7%), and 8 malignant (4.2%) lesions. Thirty-eight patients (32.2%) underwent surgery, 77 (65.3%) were monitored with imaging, and 3 (2.5%) had unresectable malignancies. Elevated carcinoembryonic antigen levels showed a trend toward predicting mucinous cysts (P = 0.062). Accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for cystic lesions were 87.3%, 86.8%, 87.5%, 76.7%, and 93.3%, respectively. CONCLUSIONS: Endoscopic ultrasound is a valuable diagnostic modality in the evaluation of cystic pancreatic neoplasms in a community hospital setting.

Unique features and insights from mucinous tumors of ovary in childhood: clinicopathological study of 15 cases including four premenarchal cases.

Mucinous tumors of ovary are primarily diagnosed in middle-aged and elder woman. They are very infrequent in the first two decades of life and exceedingly rare in premenarchal girls. We reviewed the past 20 years of our institutional pathology files and studied the clinicopathological features of the childhood ovarian mucinous tumor cases. The study concluded that ovarian mucinous tumor cases in childhood, including premenarchal cases, may not be as rare as people previously estimated and discovered some unique features of the tumors in this age group that are beneficial for better prognosis prediction and clinical management, as well as better understanding of pathogenesis of ovarian epithelial tumors.

Expression of MUC4 mucin is observed mainly in the intestinal type of intraductal papillary mucinous neoplasm of the pancreas.

OBJECTIVES: This study aimed to examine expression profile of MUC4 in intraductal papillary mucinous neoplasm of the pancreas (IPMN). METHODS: We performed immunohistochemistry (IHC) of MUC4 in 142 IPMNs, with evaluation of the specificity of 2 anti-MUC4 monoclonal antibodies, 8G7 and 1G8, in cancer cell lines. RESULTS: Monoclonal antibody 8G7 showed a clear immunoreactivity, whereas MAb 1G8 did not show any immunoreactivity, in the Western blotting and IHC for human pancreatic carcinoma cell lines expressing MUC4 messenger RNA. However, IHC signals detected by both monoclonal antibodies were observed in the tissue specimens. The expression rates of MUC4/8G7 detected by MAb 8G7 and MUC4/1G8 detected by MAb 1G8 in the intestinal-type IPMNs were significantly higher than those in the gastric-type IPMNs. In the intestinal-type IPMNs, MUC4/8G7 was expressed mainly in the cytoplasm of the neoplastic cells, whereas MUC4/1G8 was expressed mainly at the cell apexes. Even in the gastric-type IPMNs with rare MUC4 expression in the low-grade dysplasia, both MUC4 expression rates increased when dysplasia advanced. CONCLUSIONS: A significantly higher expression of MUC4 in intestinal-type IPMNs than in gastric-type IPMNs will be one of the biomarkers to discriminate between the intestinal-type IPMNs with high malignancy potential from gastric-type IPMNs with low malignancy potential.

Claudin-18 overexpression in intestinal-type mucinous borderline tumour of the ovary.

AIMS: Mucinous borderline tumours of the ovary are subclassified as intestinal-type (IMBT) and endocervical-like (EMBT), which differ in their clinicopathological features. In this study, we attempted to elucidate characteristics of the mucinous epithelium in each subtype. METHODS AND RESULTS: The expression of claudin-18, a marker of gastric differentiation, MUCs, CDX2, CK7, CK20, oestrogen receptor (ER), progesterone receptor (PgR), CA-125 and vimentin in IMBTs (n = 54), EMBTs (n = 25) and serous borderline tumours (SBTs) (n = 22) were compared by immunohistochemistry. Claudin-18 positivity was identified in 98% of the IMBTs, whereas only 4% of the EMBTs were claudin-18-positive. Expression of intestinal markers such as CDX2 and MUC2 was relatively infrequent in IMBTs (48% and 33%, respectively). Müllerian-lineage markers such as ER, PgR and vimentin were expressed rarely in IMBTs, while most EMBTs and SBTs were positive for these markers. Hierarchial clustering revealed a close association between EMBTs and SBTs, while IMBTs were clearly separate. CONCLUSIONS: Claudin-18 positivity is a specific phenotype that is characteristic of IMBTs. Frequent and diffuse expression of gastric markers, along with less frequent and usually focal expression of intestinal markers, suggests that IMBTs are essentially composed of gastrointestinal-type mucinous epithelium (gastric-type epithelium with a variable degree of intestinal differentiation).

Linear and micronodular neuroendocrine cell hyperplasia in an ovarian mucinous cystadenoma.

We report a rare case of an ovarian mucinous cystadenoma in which there were peculiar neuroendocrine micronests composed of gastrin-immunoreactive cells. There was no clinical evidence of hypergastrinemia. The mucinous component of the neoplasm was represented by columnar cells mostly expressing a gastric phenotype with MUC5AC and claudin 18 positivity, which was consistent with the presence of interspersed gastrin cells. The tumoral stroma displayed areas of luteinization with cells intensely positive for α-inhibin, MART-1 and calretinin.

Metabolomic-derived novel cyst fluid biomarkers for pancreatic cysts: glucose and kynurenine.

BACKGROUND: Better pancreatic cyst fluid biomarkers are needed. OBJECTIVE: To determine whether metabolomic profiling of pancreatic cyst fluid would yield clinically useful cyst fluid biomarkers. DESIGN: Retrospective study. SETTING: Tertiary-care referral center. PATIENTS: Two independent cohorts of patients (n = 26 and n = 19) with histologically defined pancreatic cysts. INTERVENTION: Exploratory analysis for differentially expressed metabolites between (1) nonmucinous and mucinous cysts and (2) malignant and premalignant cysts was performed in the first cohort. With the second cohort, a validation analysis of promising identified metabolites was performed. MAIN OUTCOME MEASUREMENTS: Identification of differentially expressed metabolites between clinically relevant cyst categories and their diagnostic performance (receiver operating characteristic [ROC] curve). RESULTS: Two metabolites had diagnostic significance-glucose and kynurenine. Metabolomic abundances for both were significantly lower in mucinous cysts compared with nonmucinous cysts in both cohorts (glucose first cohort P = .002, validation P = .006; and kynurenine first cohort P = .002, validation P = .002). The ROC curve for glucose was 0.92 (95% confidence interval [CI], 0.81-1.00) and 0.88 (95% CI, 0.72-1.00) in the first and validation cohorts, respectively. The ROC for kynurenine was 0.94 (95% CI, 0.81-1.00) and 0.92 (95% CI, 0.76-1.00) in the first and validation cohorts, respectively. Neither could differentiate premalignant from malignant cysts. Glucose and kynurenine levels were significantly elevated for serous cystadenomas in both cohorts. LIMITATIONS: Small sample sizes. CONCLUSION: Metabolomic profiling identified glucose and kynurenine to have potential clinical utility for differentiating mucinous from nonmucinous pancreatic cysts. These markers also may diagnose serous cystadenomas.

Nonmucinous cystadenomas of the pancreas with pancreatobiliary phenotype and ovarian-like stroma.

Among 31 benign cystic neoplasms of the pancreas diagnosed as mucinous cystadenomas, we identified 9 (29%) cases of nonmucinous cystadenomas with a pancreatobiliary phenotype and an ovarian-like stroma. Although both cystic tumors belong to the same family, they should be separated because their epithelial lining and cyst fluid are different. The lining cells of the nonmucinous cystadenomas consisted of a single layer of cuboidal cells, similar to the epithelial cells of the normal pancreatic ducts, and were not dysplastic (90%-100% of the lining cells). The cyst fluid was described as serous or clear. The remaining 22 classical mucinous cystadenomas, lined predominantly by mucinous and foveolar epithelium, revealed focal pancreatobiliary epithelium in 86% of the cases, and 6 pancreatic invasive mucinous cystadenocarcinomas failed to show pancreatobiliary differentiation. We believe that these nonmucinous cystadenomas of the pancreas represent a distinctive subset of cystic neoplasms of the pancreas that probably have no malignant potential.

Mucinous cystadenoma of the pyelocaliceal system: a report of 3 examples and an analysis of 17 previously published cases.

We report 3 patients all men between 45 and 64 years of age with unilocular or multilocular mucinous cystadenomas of the kidney. One tumor arose from the renal pelvis, and 2 involved the entire pyelocaliceal system. The tumors measured between 2.4 and 37 cm in greatest dimension. Two patients were asymptomatic, and 1 had recurrent attack of acute pyelonephritis. Microscopically, the morphology and immunophenotype (CK20, MUC2, and CDX2 positive) of the tumors were similar to the colonic adenomas. Two patients were asymptomatic 24 and 64 months after surgery, including the patient with mucinous cystadenoma and intramucosal carcinoma. One patient died of acute myocardial infarction, and his tumor was an autopsy finding. Only 17 cases of mucinous cystadenomas and 5 cases of mucinous cystadenocarcinomas have been reported. Of the 17 mucinous cystadenomas, 2 arose in horseshoe kidneys. The mean size of these neoplasms was 15 cm (2.4-37 cm). Despite their large size, some patients with mucinous cystadenomas were asymptomatic. Sixty percent were associated with renal lithiasis. Thirty percent progressed to mucinous adenocarcinomas, and only 2 cases showed areas of intramucosal carcinomas. Two cases were associated with carcinoid tumors, similar to those reported in the appendix. Most patients were asymptomatic after surgery, and only 1 patient died by abdominal sepsis related to adenomucinosis. The 3 examples of mucinous cystadenomas of the pyelocaliceal system reported here, and those previously published indicate that they are very uncommon neoplasms with morphology and intestinal immunophenotype similar to the colonic adenomas.

Expression of urokinase plasminogen activator and plasminogen activator inhibitor type-1 in ovarian cancer and its clinical significance.

The urokinase plasminogen activator system, which consists of urokinase plasminogen activator (uPA), plasminogen activator inhibitor type-1 (PAI-1) and urokinase plasminogen activator receptor (uPAR), plays an important role in tumor invasion and metastasis, and it may be a potential diagnostic biomarker and therapeutic target in cancer. It has been found that the expression of uPA and PAI-1 in ovarian cancer is related to clinical pathologies, while their effects on the biological behavior of tumor cells and their clinical significance are still unknown. In this study, 100 tissue samples (60 samples from malignant tumors, 20 from benign tumors and 20 from controls) and 147 blood samples (49 samples each from patients with malignant tumors, benign tumors and control group, respectively) were analyzed. The positive expression levels of uPA and PAI-1 in the malignant tumor samples and their serum concentrations in the malignant group were all significantly higher than these levels in the benign tumors and controls. In addition, the levels in patients with poorly differentiated and stage III-IV cancers, cancers with metastases as well as residual tumors >2 cm after surgery, were all obviously increased, consistent with their concentrations in serum. The Cox model analysis showed that expression of uPA at the transcription level had significant associations with prognosis. In addition, uPA greatly enhanced the abilities of cell invasion, migration and adhesion through its overexpression in SKOV3 cells. Collectively, our results showed that uPA and PAI-1 play important roles in ovarian cancer development; therefore, their expression in tissues and their concentrations in serum would greatly assist the diagnosis and prediction of the prognosis in ovarian cancer.

Primary retroperitoneal mucinous cystadenoma with a sarcoma-like mural nodule: an immunohistochemical study with histogenetic considerations and literature review.

Primary retroperitoneal mucinous cystadenomas (PRMCs) are extremely rare tumors and their association with sarcoma-like mural nodules (SLMNs) has not been described thoroughly. The aim of this study is to characterize the gross and microscopic features and the immunohistochemical profile of the first case of PRMC with SLMN and to discuss the differential diagnosis of SLMNs. The literature related to primary retroperitoneal mucinous tumors is reviewed in an attempt to clarify the histogenesis of the epithelial and sarcomatoid components of the associated mural nodules. A 34-yr-old woman presented with a 14-cm retroperitoneal cystic lesion with a 6-cm mural nodule. An immunohistochemical study with a panel of 19 antibodies and a histochemical study for mucin stains were performed. The epithelial component of the PRMC showed positive staining for cytokeratin (CK) 7, CK AE1/3, epithelial membrane antigen, carcinoembryonic antigen, and calretinin. The neoplasm was not immunoreactive for CK 20, CK 5/6, and the other antibodies used in this study. In addition, it stained positively for mucin by mucicarmine, periodic acid-Schiff, and Alcian blue. The stromal cells of the cyst showed estrogen receptor positivity. SLMN cells were negative for all CKs and other epithelial markers used in the study, but they showed diffuse positive staining for vimentin and CD68, and positive staining for Ki-67 was demonstrated in 25% of these cells. The immunohistochemical and histochemical profiles of PRMC were similar to those of ovarian mucinous neoplasms and the mesothelium. The formation of SLMNs seems to be related to subepithelial hemorrhage and some reactive epithelial changes near the mural nodules. The specific immunohistochemical and morphologic features of SLMNs are helpful in differentiating them from malignant mural nodules, including true sarcomas, osteoclast-rich undifferentiated carcinomas, and carcinosarcomas. Such a differentiation is critical in view of its significant impact on the management of these neoplasms, particularly in young patients who desire to preserve their fertility.

A case of a borderline mucinous tumor of the ovary with sarcoma-like mural nodules producing granulocyte colony-stimulating factor.

Borderline ovarian tumor with sarcoma-like mural nodule is rare. Malignant mural nodules usually occur in the wall of an atypical proliferative mucinous tumor or a mucinous carcinoma. The authors report one case of unfavorably progressive borderline tumor of the ovary with sarcoma-like mural nodule that produced granulocyte colony-stimulating factor (G-CSF).

Transumbilical 1-port laparoscopic resection of benign ovarian tumor.

BACKGROUND/PURPOSE: We evaluated the effectiveness of transumbilical 1-port laparoscopic resection of benign ovarian tumors in children with limited working space. METHODS: This study involved 15 children and adolescents with benign ovarian tumors treated from January 2006 to December 2010. Preoperative evaluation included physical findings, tumor markers, and imaging studies. A single surgeon performed the procedure using a 10-mm 0° operative laparoscope with a 5-mm working channel. The fallopian tube was suspended with transabdominal suspensory sutures passing through the mesosalpinx to expose the tumor and remove it after aspiration of the contents. The tumor was contained in the endobag and chopped into pieces before removal through the small umbilical wound. RESULTS: The patients' age ranged from 2 to 17 years (mean, 9.7 years). Tumor size ranged from 3.6 to 23 cm. Tumor markers including α-fetoprotein, ß-human chorionic gonadotropin, cancer antigen 125, and carcinoembryonic antigen were negative. The average operating time was 134 minutes. Except for 1 patient with associated encephalomyelitis, all patients were discharged within 3 days after surgery. Pathologic examination and follow-up studies revealed benign tumors, with no residual lesions in the abdomen or recurrence. CONCLUSIONS: Transumbilical 1-port laparoscopic resection is effective for resection of benign ovarian tumors in children, with a satisfactory cosmetic outcome. However, to prevent inadequate resection of a potential malignant lesion, thorough preoperative evaluation with physical signs, tumor markers, and imaging studies, as well as flexible intraoperative tactics, should be adopted.