A case of erythema multiforme-like rash induced by everolimus in a patient with a pancreatic neuroendocrine tumor.

A 66-year-old Japanese woman had been diagnosed with a neuroendocrine tumor of the pancreatic head (G2) 3 years previously and undergone pancreaticoduodenectomy. Nine months postoperatively, recurrence with multiple liver metastases developed and she was referred to our department. A regimen of 10 mg of everolimus for 2 weeks plus 1-week washout was instituted, and no adverse events were observed. Fourteen months after treatment initiation, she developed severe generalized erythema multiforme (EM). Skin biopsy revealed spongiosis in the epidermis and interface change and edema in the superficial dermis. Mast cells were observed from the dermis to the subcutaneous tissue, as well as perivascular eosinophilic infiltration, leading to EM being diagnosed. Oral everolimus was discontinued, and the EM was relieved by treatment including steroid therapy. Everolimus is an inhibitor of the mammalian target of rapamycin, and its indications include neuroendocrine tumors. Skin disorders are commonly seen in the early stages of everolimus treatment, but their severity is almost always mild and never severe. This is the first report on a patient who presented with severe generalized EM more than 1 year after everolimus treatment initiation. Patients on everolimus therapy should be monitored for skin disorders on a long-term basis.

Apoptosis, necroptosis and autophagy in colorectal cancer: Associations with tumor aggressiveness and p53 status.

OBJECTIVE: Cleaved caspase-3 (CC3), phosphorylated-mixed-lineage kinase domain-like protein (p-MLKL), and microtubule-associated protein-1 light chain-3B (LC3B) have pivotal functions in apoptosis, necroptosis, and autophagy, respectively. In vitro studies have shown that interaction of these proteins are complex and their roles in cancer can be influenced by many factors. However, these findings are not adequately assessed in human tissues. Here, we determined CC3, p-MLKL, and LC3B expression in colorectal cancers (CRCs), and assessed their associations with clinicopathological parameters, and with KRAS and p53 status. METHODS: We immunohistochemically assessed 113 CRC specimens for levels of CC3, p-MLKL, LC3B, and p53. KRAS gene status was analyzed using the Scorpion- amplification refractory mutation system. RESULTS: High levels of CC3 (CC3High) and LC3B (LC3BHigh) were detected in 38% and 35% of the 113 CRCs, respectively, but no or only a few p-MLKL-positive cells were observed in any of the tumors. CC3High was significantly associated with high pT status (P = 0.03), vascular invasion (P = 0.03) and high pStage (P = 0.04) and was marginally associated with lymph node (P = 0.06) and distant metastases (P = 0.06). LC3BHigh was also significantly associated with high pT status (P = 0.02) and lymphatic invasion (P = 0.002), and was marginally associated with nerve plexus invasion (P = 0.06). In combined analysis, compared with CC3Low/LC3BLow tumors, tumors that were either CC3High, LC3BHigh, or both were significantly associated with high pT status (P = 0.0007), lymphatic invasion (P = 0.03), vascular invasion (P = 0.003), distant metastasis (P = 0.04) and high pStage (P = 0.04). LC3BHigh was significantly associated with a mutant-type expression pattern of p53 (P = 0.003). CONCLUSION: To the best of our knowledge, this is the first study to examine the combination of CC3/LC3B and p-MLKL expression in clinical CRC samples and to correlate these expression data with clinicopathological parameters and EGFR and p53 status. Our results suggest that necroptosis is a rare process in CRC, apoptosis and autophagy are upregulated in aggressive CRCs, and p53 mutation may lead to the upregulation of autophagy.

Anal Canal Duplication Associated with Presacral Cyst in an Adult.

Anal canal duplication (ACD) is a rare congenital malformation, usually detected early in life. We report a case of a 67-year-old female with symptomatic ACD associated with a presacral cyst. Physical examination revealed an accessory opening located in the midline, posterior to the true anus. Imaging examinations, including fistulography, endoanal ultrasonography, and magnetic resonance imaging, revealed a blind-ending fistulous tract without connecting with the rectum and a presacral cyst posterior to the rectum. Complete surgical excision of the tract with cyst was performed through a posterior sagittal approach. Histologic examination revealed squamous epithelium lining and smooth muscle bundles, thereby confirming ACD. The postoperative course was uneventful, and the patient was doing well; no recurrence was observed 4 years after surgery. ACD can present for the first time in infants, children, and adults. Imaging examinations are useful for the diagnosis and preoperative assessment of ACD. Therefore, ACD should be considered in the differential diagnosis, even in adults, when a posterior perineal orifice is encountered, particularly in female patients. Once ACD is suspected, intense imaging inspection is recommended to visualize the ACD and associated anomalies, and surgical removal is warranted to prevent inflammatory complications or malignant changes.

Endoanal Ultrasonography of Mucinous Adenocarcinoma Arising from Chronic Fistula-in-ano: Three Case Reports.

Mucinous adenocarcinoma arising in chronic fistula-in-ano is rare, and diagnosing it at an early stage is difficult. The role of endoanal ultrasonography in diagnosing the condition has not been discussed in the study. Herein, we report three cases of mucinous adenocarcinoma arising from anal fistulas in which endosonography played an important role in diagnosing malignant change. Three male patients with a 5- to 20-year history of anal fistula were referred to our hospital due to perianal induration, progressive anal pain, or mucopurulent secretion. In all three patients, endosonography revealed a multiloculated complex echoic mass with isoechoic solid components communicating with a trans-sphincteric fistula and sonography-guided biopsy under anesthesia revealed mucinous adenocarcinoma. All patients underwent abdominoperineal resection with lymph node dissection. One patient with a local recurrence died 3 years after surgery and two have remained disease-free for >6 years. These observations suggest that endosonography may be a reliable technique for the diagnosis of mucinous adenocarcinoma arising from chronic fistula-in-ano. Sonography-guided biopsy is useful for the definitive diagnosis of malignancy. Therefore, periodic endosonography assessment should be recommended for patients with persistent anal fistula, especially those with progressive clinical symptoms. Once malignancy is suspected, aggressive sonography-guided biopsy under anesthesia should be performed, which may enable an early diagnosis, curative treatment, and favorable long-term results.

Human Nanog pseudogene8 promotes the proliferation of gastrointestinal cancer cells.

There is emerging evidence that human solid tumor cells originate from cancer stem cells (CSCs). In cancer cell lines, tumor-initiating CSCs are mainly found in the side population (SP) that has the capacity to extrude dyes such as Hoechst 33342. We found that Nanog is expressed specifically in SP cells of human gastrointestinal (GI) cancer cells. Nucleotide sequencing revealed that NanogP8 but not Nanog was expressed in GI cancer cells. Transfection of NanogP8 into GI cancer cell lines promoted cell proliferation, while its inhibition by anti-Nanog siRNA suppressed the proliferation. Immunohistochemical staining of primary GI cancer tissues revealed NanogP8 protein to be strongly expressed in 3 out of 60 cases. In these cases, NanogP8 was found especially in an infiltrative part of the tumor, in proliferating cells with Ki67 expression. These data suggest that NanogP8 is involved in GI cancer development in a fraction of patients, in whom it presumably acts by supporting CSC proliferation.

HER-2/neu gene amplification in carcinoma ex pleomorphic adenoma in relation to progression and prognosis: a chromogenic in-situ hybridization study.

AIMS: The aim of this study was to investigate the potential role of HER-2/neu in the stepwise progression of carcinoma ex pleomorphic adenoma (CXPA) and to evaluate its prognostic significance in CXPA. METHODS AND RESULTS: We examined HER2 overexpression and HER2 amplification by immunohistochemistry and chromogenic in-situ hybridization in 31 cases of CXPA with ductal differentiation (eight intraductal, five intracapsular, and 18 extracapsular) and seven cases of atypical pleomorphic adenoma (PA). HER2 overexpression and HER2 amplification were found in 17 (54.8%) and 12 (38.7%) of the 31 CXPA cases, respectively. HER2 amplification was more prevalent in extracapsular CXPAs (9/18 cases; 50%) than intracapsular CXPAs (1/5 cases; 20%), intraductal CXPAs (2/8 cases; 25%), or atypical PAs (0/7 case; 0%). The status of HER2 amplification was essentially retained from the intraductal to the extracapsular component in individual extracapsular CXPAs. In addition, HER2 amplification was significantly associated with a worse prognosis (shorter disease-free survival time and shorter overall survival time) among extracapsular CXPAs (each P < 0.05). CONCLUSIONS: These results suggest that HER2 may play an important role in the progression of CXPA, and that HER2 amplification may be an additional prognostic indicator of CXPA.

Liver-intestine cadherin expression is associated with intestinal differentiation and carcinogenesis in intraductal papillary mucinous neoplasm.

OBJECTIVES: Intraductal papillary mucinous neoplasms (IPMN) are classified into four phenotypes according to the WHO classification. Recently, intestinal-type IPMN has been suggested to grow with a distinct carcinogenetic pathway. Like mucin 2, oligomeric mucus/gel forming (MUC2) and caudal-related homeobox 2 (CDX2), liver-intestine cadherin (LI cadherin) is an intestine-specific marker. We aimed to investigate the roles of LI cadherin expression in IPMN. METHODS: We examined LI cadherin expression in 135 cases of IPMN by immunohistochemical staining and the quantitative real-time reverse-transcription polymerase chain reaction. RESULTS: LI cadherin protein and mRNA levels were significantly higher in intestinal-type IPMN than in nonintestinal-type IPMN (protein level, p < 0.001; mRNA level, p = 0.0312). A positive correlation was found between protein and mRNA of LI cadherin (p = 0.0037). The positivity rates of LI cadherin expression were significantly higher in CDX2-positive cases than in CDX2-negative cases (p < 0.001). In 41 intestinal-type IPMNs, LI cadherin-positive rates tended to increase gradually, from IPMN with low-grade dysplasia (IPMN-L) to IPMN with an associated invasive carcinoma (IPMN-IC) [IPMN-L vs. IPMN with high-grade dysplasia (IPMN-H); p = 0.0357, IPMN-L vs. IPMN-IC; p = 0.0230] and positively correlated with the Ki-67 labeling index (p = 0.0408), whereas this tendency was not recognized in nonintestinal-type IPMNs. CONCLUSIONS: LI cadherin is associated with an intestinal phenotype and an 'intestinal pathway' of carcinogenesis in IPMN.

Expression level of the mitotic checkpoint protein and G2-M cell cycle regulators and prognosis in gastrointestinal stromal tumors in the stomach.

The biological behavior of gastrointestinal stromal tumors (GISTs) ranges from benign to malignant, and the risk of an adverse outcome is correlated with the location of the primary tumor, tumor size, and mitotic counts. Cell cycle regulators are potentially associated with the tumorigenesis and progression of GISTs. Checkpoint with forkhead and ring finger (CHFR) functions as an important checkpoint protein in the early to mid-prophase to regulate mitosis. In this study, we evaluated the expression of CHFR and several cell cycle regulators, including cyclin A, cyclin B1, cdc2, and cdk2, by immunohistochemical staining in 53 cases of primary gastric GISTs, and compared the immunohistochemical results with the clinicopathological factors or the GIST risk grades as modified by Miettinen et al. Of the 53 cases, 18 (34%) showed decreased nuclear CHFR expression. Decreased CHFR expression was correlated with higher mitotic counts [>5/50 high-power fields (HPFs)] (p = 0.039) and a high-risk grade (p = 0.0475), but not with expression of other cell cycle regulators. Higher cyclin A labeling index (LI, >1.5%), cyclin B1 LI (>0.25%), cdc2 LI (>1.16%), Ki-67 LI (>4.9%), mitotic counts (>5/50 HPF) and high-risk grade were each associated with shorter disease-free survival (p = 0.0017, p = 0.003, p = 0.0471, p = 0.002, p < 0.001, and p = 0.0017, respectively). Our results suggest that modified risk grade and increased expression of G2-M regulators such as cyclin A, cyclin B1, and cdc2 are useful for predicting the biological behavior of gastric GISTs. In addition, decreased CHFR expression may play a role in increased proliferative activity of higher grade GISTs.

Inhibin-α and synaptophysin immunoreactivity in synovial sarcoma with granular cell features.

We recognized immunoreactivity for the α subset of inhibin and synaptophysin in synovial sarcomas with granular cell features. Histologic findings of 90 cases of synovial sarcoma were reviewed. Two (2.2%) of the 90 cases had granular cell features, showing sheet or nested proliferation of characteristic epithelioid cells with abundant eosinophilic and granular cytoplasm, in addition to the typical spindle cell component. The 2 cases were both female (aged 86 and 76 years). The tumors were located in the foot and the retroperitoneum and measured 3.5 and 14 cm in maximum diameter. Reverse transcriptase polymerase chain reaction analysis revealed SS18-SSX1 transcripts in both cases. SS18 gene rearrangement was detected in granular cells as well as spindle cells by chromogenic in situ hybridization. Immunohistochemistry found the granular cells to be positive for inhibin-α in both cases and for synaptophysin in 1 case, whereas spindle cells were not. Thirty-six cases (20 monophasic fibrous, 11 biphasic, and 5 poorly differentiated synovial sarcomas) were additionally examined for comparison; they showed no immunoreactivity for inhibin-α or synaptophysin. This is the first report of immunoreactivity for inhibin-α and synaptophysin in synovial sarcoma. These immunohistochemical findings might be characteristic of synovial sarcomas with granular cell features.

Sclerosing variant of perivascular epithelioid cell tumor in the female genital organs.

Perivascular epithelioid cell tumor (PEComas), other than angiomyolipoma, clear cell 'sugar' tumor of the lung, and lymphangioleiomyomatosis, is an uncommon mesenchymal neoplasm that arises in the soft tissue and visceral organs. We report herein two cases of sclerosing PEComa; a distinctive variant of PEComa, which is characterized by extensive stromal hyalinization, occurring in the uterus and broad ligament. The patients were 34- and 51-year-old females with no family history of tuberous sclerosis complex. Macroscopically, the tumors had white to gray cut surfaces and were microscopically composed of predominantly spindle- to polygon-shaped cells with clear to slightly eosinophilic cytoplasm and pleomorphic nuclei focally arranged in a perivascular pattern, accompanied by marked stromal hyalinization. These tumor cells were immunohistochemically positive for HMB45 and α-smooth muscle actin. Although this variant of PEComa is very rare, this entity should be considered as a potential primary neoplasm of the female genital organs.

Abnormalities of the Wnt/ß-catenin signalling pathway induce tumour progression in sporadic desmoid tumours: correlation between ß-catenin widespread nuclear expression and VEGF overexpression.

AIMS: To analyse the correlation between ß-catenin and vascular endothelial growth factor (VEGF) in sporadic desmoid tumours. METHODS AND RESULTS: The correlation between ß-catenin aberrant expression and VEGF overexpression was examined and microvessel density (MVD) assessed by immunohistochemical expression of CD31 in 74 samples (63 primary and 11 recurrent samples, 63 patients) of sporadic desmoid tumours without familial adenomatous polyposis (FAP). ß-catenin gene mutation and mRNA expression of VEGF was then examined by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). There was a statistically significant correlation between widespread nuclear expression of ß-catenin and overexpression of VEGF in all desmoid tumours (P = 0.04, Fisher's exact test). MVD in recurrent tumours was significantly higher than that in primary tumours. CONCLUSIONS: Abnormalities of ß-catenin and VEGF overexpression play an important role in the neoplastic progression of sporadic desmoid tumours.

Expression of activation-induced cytidine deaminase in ulcerative colitis-associated carcinogenesis.

AIMS: Activation-induced cytidine deaminase (AID) is a DNA/RNA-editing enzyme that is essential for hypermutation and class-switch recombination in immunoglobulin genes. The aim of this study was to investigate the expression of AID and its association with p53 mutation in ulcerative colitis (UC)-associated carcinogenesis. METHODS AND RESULTS: The expression of AID was examined in 25 patients with UC-associated neoplasia, 20 UC patients without neoplasia, 18 patients with non-inflamed colorectal mucosa unaffected by UC, and 19 patients with sporadic colorectal cancer, by immunohistochemistry and quantitative reverse transcription polymerase chain reaction analysis. Mutational analysis and immunohistochemistry for p53 were also performed. The degree of AID expression was not different between UC-associated neoplasia and sporadic colorectal cancer. However, AID was expressed in both UC-associated neoplasia and UC without neoplasia. Whereas AID expression in UC-associated neoplasia was not correlated with the grade of dysplasia, expression in non-neoplastic mucosa of UC was correlated with the histological grade of inflammation. In UC-associated neoplasia, there was no significant correlation between AID expression and p53 mutation. CONCLUSIONS: AID is associated with inflammation in UC, whereas it may not specifically contribute to carcinogenesis in UC.

Nuclear atypia grading score is a useful prognostic factor in papillary gastric adenocarcinoma.

AIMS: To investigate nuclear atypical in papillary gastric adenocarcinoma (PGA). METHOD AND RESULTS: Hundred cases of PGA were classified into two groups according to nuclear pleomorphism and nuclear polarity; these groups were designated as high nuclear grade and low nuclear grade. Correlations between nuclear grade and clinicopathological features were evaluated for prognostic value. In order to evaluate which types of biological factors influence nuclear atypia, the expression of gastric-type mucin phenotype, p53, HER2 and Ki-67 detected by immunohistochemistry and DNA ploidy detected by laser scanning cytometry. The high nuclear grade group correlated with deeper wall invasion, the presence of lymphatic and venous invasion and the positivity of lymph node metastasis. High nuclear grade was an independent prognostic factor for disease-free survival. Moreover, significant correlations were observed between high nuclear grade and positivity of gastric-type mucin phenotype, p53 and HER2 and DNA aneuploidy. CONCLUSION: Nuclear grade could be a new and useful morphological predictor for high malignant potential in PGA.

Histological and immunohistological findings in biliary intraepithelial neoplasia arising from a background of chronic biliary disease compared with liver cirrhosis of non-biliary aetiology.

AIMS: Hitherto, biliary intraepithelial neoplasia (BilIN) has been described in chronic biliary disease but rarely in non-biliary liver cirrhosis (LC). Intraepithelial neoplasia of the pancreas shows alterations in the expression of cell cycle and mucin core proteins. The aim of this study was to evaluate BilIN and reactive biliary lesions in biliary disease and non-biliary LC. METHODS AND RESULTS: BilIN was found in 51% (33 of 65) of liver tissue cases of biliary disease, and in 11% (34 of 310) of the LC group. Immunohistologically, MUC5AC, an 'early phase' protein, and Ki67, reflecting 'late phase' expression, were identified with increasing degrees of dysplasia in both groups, but that expression was significantly higher in the biliary disease group. 'Early phase' cell cycle proteins, p16 (decrease) and p21 (increase) altered in both biliary and LC groups with increasing degrees of dysplasia. CONCLUSIONS: We found BilIN in the large bile ducts of hepatitis B virus- and hepatitis C virus-related LC as well as in cases related to a biliary aetiology. The LC group was significantly less likely to show changes in the expression of MUC5AC and proliferative activity than the biliary group. Alterations in p16 and p21 reflected increasing degrees of dysplasia in both groups.

Senescence in intraductal papillary mucinous neoplasm of the pancreas.

Intraductal papillary mucinous neoplasm of the pancreas is attracting attention as a precursor lesion of the invasive ductal adenocarcinoma, whereas it has been reported that some intraductal papillary mucinous neoplasms do not display progression to malignancy and remain almost unchanged in size and morphology. Recent studies have reported that oncogene-induced senescence has been observed in neoplasms, especially in premalignant lesions, and that it can play an important role in preventing malignant progression. To clarify the presence of senescence in intraductal papillary mucinous neoplasms, we analyzed the expression of several markers of senescence. The intraductal papillary mucinous neoplasms evaluated in this study were classified into 4 groups according to the degree of dysplasia. Senescence-associated ß-galactosidase activity and senescence-associated heterochromatin foci formation were investigated in 33 cases of intraductal papillary mucinous neoplasms and 6 normal controls. Immunohistochemical analysis of p16(INK4a) and p15(INK4b) was performed in 158 cases of intraductal papillary mucinous neoplasms and 10 normal controls. In the normal controls, neither senescence-associated ß-galactosidase activity nor senescence-associated heterochromatin foci formation was observed. Most of the normal epithelia were negative for either p16(INK4a) or p15(INK4b). For all 4 markers, the percentages of positive cases reached a peak in intraductal papillary mucinous neoplasm with low-grade dysplasia and showed significant decreasing trends in the transition from intraductal papillary mucinous neoplasm with low-grade dysplasia to intraductal papillary mucinous neoplasm with an associated invasive carcinoma. Our results indicate that senescence is induced in the early stage of intraductal papillary mucinous neoplasm and gradually attenuated according to the progression. It is suggested that senescence plays a role in preventing malignant progression of intraductal papillary mucinous neoplasm.

Heterozygosity loss at 22q and lack of INI1 gene mutation in gastrointestinal stromal tumor.

OBJECTIVES: Gastrointestinal stromal tumor (GIST) is characterized by KIT or PDGFRA gene mutation. Although chromosomal losses of 22q are frequent in GIST, it is unclear which tumor suppressor genes might be inactivated in association with such losses. The INI1 gene, located at 22q11.23, is a tumor suppressor gene that is frequently altered in malignant rhabdoid tumor. METHODS: To elucidate the hypothesis that the INI1 gene might be altered along with 22q loss in GIST, we examined the loss of heterozygosity (LOH) at 22q11.23, homozygous deletion and mutation of the INI1 gene, and its gene product expression as well as mutations of KIT and PDGFRA in 27 cases of GIST. RESULTS: Among the 27 informative cases, 19 (70.4%) showed LOH of at least one of the microsatellite markers on 22q11.23. None of the cases (0%) showed homozygous deletion or mutation of the INI1 gene. Immunohistochemically, the INI1 expression was focally reduced in 17/27 (63%) cases, and the INI1 protein level and INI1 mRNA level were each correlated with the presence of 22q11.23 LOH. Although the 22q11.23 LOH was more frequently present in high- than in low-grade tumors, INI1 expression level was not correlated with tumor grade, tumor size, proliferative activity and the expression levels of cyclin D1 and p16INK4a. KIT mutations were found in 18/27 (66.7%) GISTs; however, the KIT genotype was not correlated with the status of LOH at 22q11.23. CONCLUSIONS: The results suggest that 22q11.23 LOH is frequently present in GIST irrespective of KIT genotype and it might play a role in part of the development of GIST. However, the hemiallelic loss of INI1 gene causing reduced expression of INI1 protein probably does not have a major impact in the progression of GIST.

Aberrant activation-induced cytidine deaminase expression is associated with mucosal intestinalization in the early stage of gastric cancer.

Although Helicobacter pylori is a risk factor for gastric cancer (GC), its detailed carcinogenesis remains unclear. Recently, aberrant expression of activation-induced cytidine deaminase (AID) was demonstrated in gastric epithelium with H. pylori infection and seems to cause the accumulation of mutation. This investigation aims to elucidate whether or not AID expression plays an important role in the carcinogenesis of early GC. We examined the correlation between immunohistochemical AID expression and histological characteristics, including pre-existing chronic gastritis and cellular mucin phenotype in 138 cases of intramucosal GC. Furthermore, we investigated the relationship between AID, p53 protein, and ß-catenin. The low degree of polymorphonuclear neutrophil activity, and the high degree of glandular atrophy and intestinal metaplasia were significantly correlated with the high levels of AID expression in non-neoplastic mucosa (P = 0.007, P ≤ 0.001, and P = 0.003). With regard to mucin phenotype of carcinoma, the intestinal phenotype tended to have the higher AID expression levels (P = 0.052). AID showed close correlations with Cdx2 and nuclear staining of ß-catenin (P = 0.003, P = 0.034). As for p53 protein, no correlation was found with AID expression. Our findings suggest that aberrant AID expression is correlated with persistent inflammatory condition induced by H. pylori infection and may contribute to the development of GC through an inflammatory condition and intestinalization.

Histologic classification of microscopic portal venous invasion to predict prognosis in hepatocellular carcinoma.

Portal venous invasion is one of the most important prognostic factors after surgical resection of hepatocellular carcinoma. Microscopic portal venous invasion can be evaluated histologically. We examined 280 hepatocellular carcinomas with microscopic portal venous invasion (n = 125) or without it (n = 155) for 3 characteristics: the number of invaded portal vessels, the maximum number of invading carcinoma cells, and the farthest distance from the tumor. Univariate analysis of overall and disease-free survival revealed that the number of invaded portal vessels and the number of invading carcinoma cells were poor prognostic factors. Therefore, we classified patients with microscopic portal venous invasion into 2 groups: a high-microscopic portal venous invasion group, in which there were multiple invaded portal venous vessels (≥2) and more than 50 invading carcinoma cells (n = 57), and a low-microscopic portal venous invasion group, in which microscopic portal venous invasion was observed but with invasion of only a single portal venous vessel or fewer than 50 invading carcinoma cells (n = 68). The high-microscopic portal venous invasion group showed significantly higher α-fetoprotein levels, larger tumor size, and higher frequencies of poorly differentiated histology, capsule infiltration, and intrahepatic metastasis compared with the low-microscopic portal venous invasion group (P = .0496, P < .0001, P = .0431, P = .0180, and P = .0012, respectively). The high-microscopic portal venous invasion group showed poorer overall survival and disease-free survival rates than the low-microscopic portal venous invasion group (P = .0004 and P = .0003), and the high-microscopic portal venous invasion group was an independent prognostic factor for disease-free survival (P = .0259). We proposed a new definition for classifying microscopic portal venous invasion and documented the necessity of definite histologic evaluation of it.

Invasive carcinoma derived from intestinal-type intraductal papillary mucinous neoplasm is associated with minimal invasion, colloid carcinoma, and less invasive behavior, leading to a better prognosis.

OBJECTIVES: Although intestinal-type intraductal papillary mucinous carcinoma (IPMC) is reported to have a better prognosis, few studies have addressed its invasive pattern. The meaning of "minimal invasion" (MI) in IPMC also remains unclear. We investigated the prognosis of intraductal papillary mucinous neoplasm (IPMN) focusing on MI and subtypes. METHODS: We evaluated 71 patients with IPMC among a total of 179 patients with resected IPMN. RESULTS: Although 2 of 10 MI-IPMC patients had lymph node metastasis, there were no disease-specific deaths among the MI-IPMC patients. Minimally invasive IPMCs were more frequently observed in intestinal-type IPMC (23/33 cases) than in non-intestinal-type IPMCs (16/38 cases; P = 0.019). Among 32 patients with massively invasive IPMC, the prognosis was significantly better for patients with intestinal-type IPMC than for patients with non-intestinal-type IPMC (P = 0.013). When confined to massively invasive IPMC, tubular invasion (P < 0.001) and lymphatic (P = 0.001) or serosal (P = 0.021) invasion were less frequently observed in intestinal-type IPMC than in non-intestinal-type IPMC. CONCLUSIONS: Invasive carcinoma derived from intestinal-type IPMN is associated with MI, colloid carcinoma, and less invasive behavior.

The significance of strong histone deacetylase 1 expression in the progression of prostate cancer.

AIMS: Histone deacetylases (HDACs) play important roles in many types of cancer. Recently, it has been reported that HDAC1 expression in prostate cancer is significantly higher than in benign prostate cell lines and tissues. The expression of HDAC1 in association with the clinicopathological data was investigated to define its functional and pathological roles in prostate cancer. METHODS AND RESULTS: HDAC1 expression was examined immunohistochemically in 148 patients with prostate cancer. Strong expression of HDAC1 in benign prostate glands, high-grade prostatic intraepithelial neoplasia (PIN) and prostate cancer was observed in 17/148 (11%), 19/71 (27%) and 69/148 (47%) patients. Strong HDAC1 expression was correlated with high Gleason score (P = 0.025) and high pT stage (P = 0.012). Patients with strong HDAC1 expression had higher biochemical recurrence rates (P = 0.0010). Furthermore, strong HDAC1 expression had a significant impact on patient biochemical recurrence rates in multivariate analysis (P = 0.004). CONCLUSIONS: These results indicate that overexpression of HDAC1 contributes to progression and poor prognosis in prostate cancer. The findings may play an important role in the emergence of effective new approaches for therapy and prognostic markers of prostate cancer.