Diagnostic extended usefulness of RMI: comparison of four risk of malignancy index in preoperative differentiation of borderline ovarian tumors and benign ovarian tumors.

BACKGROUND: This study aimed to examine the performance of the four risk of malignancy index (RMI) in discriminating borderline ovarian tumors (BOTs) and benign ovarian masses in daily clinical practice. METHODS: A total of 162 women with BOTs and 379 women with benign ovarian tumors diagnosed at the Second Affiliated Hospital of Harbin Medical University from January 2012 to December 2016 were enrolled in this retrospective study. Also, we classified these patients into serous borderline ovarian tumor (SBOT) and mucinous borderline ovarian tumor (MBOT) subgroup. Preoperative ultrasound findings, cancer antigen 125 (CA125) and menopausal status were reviewed. The area under the curve (AUC) of receiver operator characteristic curves (ROC) and performance indices of RMI I, RMI II, RMI III and RMI IV were calculated and compared for discrimination between benign ovarian tumors and BOTs. RESULTS: RMI I had the highest AUC (0.825, 95% CI: 0.790-0.856) among the four RMIs in BOTs group. Similar results were found in SBOT (0.839, 95% CI: 0.804-0.871) and MBOT (0.791, 95% CI: 0.749-0.829) subgroups. RMI I had the highest specificity among the BOTs group (87.6, 95% CI: 83.9-90.7%), SBOT (87.6, 95% CI: 83.9-90.7%) and MBOT group (87.6, 95% CI: 83.9-90.7%). RMI II scored the highest overall in terms of sensitivity among the BOTs group (69.75, 95% CI: 62.1-76.7%), SBOT (74.34, 95% CI: 65.3-82.1%) and MBOT (59.18, 95% CI: 44.2-73.0%) group. CONCLUSION: Compared to other RMIs, RMI I was the best-performed method for differentiation of BOTs from benign ovarian tumors. At the same time, RMI I also performed best in the discrimination SBOT from benign ovarian tumors.

Frequent CpG island methylation: a risk factor in the progression of traditional serrated adenoma of the colorectum.

BACKGROUND: Traditional serrated adenoma (TSA) features a unique serrated configuration because it involves two cell types: tall and short columnar cells. The serrated neoplasia pathway is related to the carcinogenesis of colorectal cancer. CpG island methylator phenotype-high (CIMP-high) is a unique genetic alteration in this pathway. MATERIALS AND METHODS: This study investigated the prevalence and level of methylation and CIMP in 30 TSA cases. The tall and short cells in 28 TSAs were separated by microdissection. Methylation-specific PCR was performed to detect the methylation of MGMT, MLH1, P14, P16, MINT1, MINT2 and MINT31. RESULTS: Overall, 30 cases presented CIMP-high, and the prevalence of CIMP-high was 100% (30/30) in tall cells and 93% (28/30) in short cells. CONCLUSIONS: No significant difference was found between tall and short columnar cells. The relationship between methylation and clinicopathological characters remains to be established.

Smoking is an independent association of squamous metaplasia in Chinese nasal polyps.

BACKGROUND: Nasal polyposis demonstrates histological features of epithelial remodeling and variable inflammatory cellular infiltration. We studied a large series of Chinese nasal polyp (NP) samples to characterize these histological features and their associations with clinical characteristics. METHODS: A detailed histological study of nasal polyposis was performed employing various histopathological techniques. A total of 153 intraoperative NP biopsies were analyzed histologically. Sections were examined under microscopy to determine the percentages of different types of inflammatory cells, and types of epithelial remodeling. Two systems of subtyping NPs based on inflammatory cell infiltration were assessed. These were correlated with patient characteristics. RESULTS: Epithelial remodeling patterns include epithelial hyperplasia (87.8% of specimens), goblet cell hyperplasia (53.2%), and squamous metaplasia (44.6%). Smoking was a strong independent association of squamous metaplasia (adjusted odds ratio [OR] 9.9; 95% confidence interval [CI], 4.2 to 22.9; p < 0.01). The most common inflammatory cells were neutrophils (median of 12.8%) and CD8+ T cells (12.8%), followed by macrophages (11.0%), CD4+ T cells (9.7%), eosinophils (8.6%), and mast cells (7.6%). We defined 2 systems to classify NPs based on proportions of eosinophils and neutrophils. The majority of NP samples were neutrophilic. The first classification system has greater histological correlation. Based on the first classification, eosinophilic nasal polyposis was associated with epithelial hyperplasia (OR 3.7, p = 0.019) and goblet cell hyperplasia (OR 3.4, p < 0.001). CONCLUSION: The majority of Chinese NPs are neutrophilic and epithelial hyperplasia is the most common pattern of epithelial remodeling. We show for the first time that smoking has a strong association with squamous metaplasia in nasal polyposis.

The T-SPOT.TB Test for Diagnosis of Breast Tuberculosis.

OBJECTIVE: To assess the diagnostic value of the T-SPOT.TB test in cases of breast turberculosis (BTB) in China. METHODS: We enrolled 13 female patients with primary BTB as the BTB test group and 10 healthy volunteers as the control group. The 2 groups underwent T-SPOT.TB tests and tuberculin skin tests (TSTs) before receiving a core-needle biopsy or excision biopsy. We then collected and analyzed T-SPOT.TB and TST data. RESULTS: The sensitivity of the T-SPOT.TB test for detection of BTB (84.6%) was significantly greater than that of TST (53.8%) (P <.05); the specificity of each test (80.0% and 60.0%, respectively) for BTB was not significantly different (P >.05). CONCLUSION: The T-SPOT.TB test could be a useful adjunct to current tests for diagnosis of BTB and could be used for early diagnosis of this condition.

Arbutin, an intracellular hydroxyl radical scavenger, protects radiation-induced apoptosis in human lymphoma U937 cells.

Ionizing radiation (IR) can generate reactive oxygen species (ROS). Excessive ROS have the potential to damage cellular macromolecules including DNA, proteins, and lipids and eventually lead to cell death. In this study, we evaluated the potential of arbutin, a drug chosen from a series of traditional herbal medicine by measuring intracellular hydroxyl radical scavenging ability in X-irradiated U937 cells. Arbutin (hydroquinone-ß-D-glucopyranoside), a naturally occurring glucoside of hydroquinone, has been traditionally used to treat pigmentary disorders. However, there are no reports describing the effect of arbutin on IR-induced apoptosis. We confirmed that arbutin can protect cells from apoptosis induced by X-irradiation. The combination of arbutin and X-irradiation could reduce intracellular hydroxyl radical production and prevent mitochondrial membrane potential loss. It also could down-regulate the expression of phospho-JNK, phospho-p38 in whole cell lysate and activate Bax in mitochondria. Arbutin also inhibits cytochrome C release from mitochondria to cytosol. To verify the role of JNK in X-irradiation-induced apoptosis, the cells were pretreated with a JNK inhibitor, and found that JNK inhibitor could reduce apoptosis induced by X-irradiation. Taken together, our data indicate that arbutin plays an anti-apoptotic role via decreasing intracellular hydroxyl radical production, inhibition of Bax-mitochondria pathway and activation of the JNK/p38 MAPK pathway.

Isofraxidin, a potent reactive oxygen species (ROS) scavenger, protects human leukemia cells from radiation-induced apoptosis via ROS/mitochondria pathway in p53-independent manner.

Ionizing radiation (IR) leads to oxidizing events such as excessive reactive oxygen species (ROS) in the exposed cells, resulting in further oxidative damage to lipids, proteins and DNA. To screen the potential radio-protective drug, the intracellular ROS was measured in irradiated U937 cells pretreated with 80 candidate traditional herbal medicine, respectively. Isofraxidin (IF) was one possible radio-protector in these 80 drugs. This study investigated the radio-protective role of IF, a Coumarin compound, in human leukemia cell lines, for the first time. Results indicate that IF protects against IR-induced apoptosis in U937 cells in the time- and concentration- dependent manner. IF decreases IR-induced intracellular ROS generation, especially hydroxyl radicals formation, inhibits IR-induced mitochondrial membrane potential loss and reduces IR-induced high intracellular Ca(2+) levels regardless of ER stress. IF down-regulates the expression of caspase-3, phospho-JNK, phospho-p38 and activates Bax in mitochondria. IF inhibits cytochrome c release from mitochondria to cytosol. IF also moderates IR-induced Fas externalization and caspase-8 activation. IF also exhibits significant protection against IR-induced cell death in other leukemia cell lines such as Molt-4 cells and HL60 cells regardless of p53. Taken together, the data demonstrate that IF protects leukemia cells from radiation-induced apoptosis via ROS/mitochondria pathway in a p53-independent manner.

The relationship between mucin phenotype and clinicopathological factors, proliferative activity and p53 expression in gastric hyperplastic polyps.

AIMS: Gastric hyperplastic polyps (GHPs) are the most common polypoid lesion of the stomach, and their malignant potential has been demonstrated. In the present study, we evaluated the mucin phenotypes of GHPs and investigated the relationships among mucin phenotypes and clinical-pathological factors, proliferative activity and p53 expression in GHPs. METHODS: The CD10, MUC2, MUC5AC and MUC6 expression patterns of 238 GHPs were examined by immunohistochemical staining. The GHP mucin phenotypes were divided into 4 subtypes: the gastric mucin phenotype (G-type), the intestinal mucin phenotype (I-type), the mixed or gastrointestinal mucin phenotype (GI-type) and the unclassified mucin phenotype (U-type). RESULTS: The G and GI types were observed in 58% and 42% of the GHPs, respectively. However, no I or U type GHPs were found in the present study. The GI type was more common in lesions with dysplasia or carcinoma than in polyps without dysplasia or carcinoma (P<0.001). P53-positivity rate and high index of Ki-67 tumors were significantly more common in the GI-type than in the G-type polyps (P<0.001). CONCLUSIONS: The mucin phenotype may serve as a useful marker for the malignant potential of GHPs, and GI-type GHPs should be considered to be a lesion with malignant potential.

BRAF mutation is associated with the unique morphology of traditional serrated adenoma of the colorectum.

Traditional serrated adenoma (TSA) consists of glands with tall cells and short cells. Two kinds of cells alternate to give a unique serrated configuration. The aim of this study was to identify the relationship between the alterations of both Wnt and serrated pathways and the unique morphology of TSAs. The tall and short cells in 28 TSAs were separated by microdissection. Semi-nested polymerase chain reaction was performed to detect the mutations of BRAF, ß-catenin, APC, and KRAS. BRAF mutations were observed in 22 of 28 (78.6%) TSAs, and all mutations occurred at the tall cells. In conclusion, BRAF mutation is associated with the serrated morphology of TSAs. Genetic alterations in both the serrated pathway and the Wnt signaling pathway may both contribute to TSAs.

Molecular analysis of single isolated glands in gastric cancers and their surrounding gastric intestinal metaplastic mucosa.

The biological properties and underlying genetics of gastric cancer and gastric intestinal metaplasia evolve with neoplastic progression from the genetics of the original gland cell. PCR assay with crypt isolation was used in tumors from 20 patients to examine microsatellite alterations (allelic imbalance at 17p, 5q, 18q, 3p, 4p, and 9p, and microsatellite instability) in glands from each tumor and from intestinal metaplastic lesions. Tumor specimens were processed as either pooled-gland samples or single-gland samples. Pooled gland sample was composed of 10-20 tumor glands, intestinal metaplastic glands, or nonmetaplastic glands. Single gland sample was 10 tumor glands from tumor and single gland sample was 5 gastric intestinal metaplastic and 5 nonmetaplastic glands from its surrounding metaplastic mucosa. Multiple genetic alterations were found in individual tumor glands, with various subclonal expansions seen within the same tumor. Although microsatellite instability was found in 2 of 20 tumor single-gland samples, none was detected in metaplastic single-gland samples. Most cancers appear to have a heterogeneous composition. On the other hand, microsatellite alterations were also detected within the nonmetaplastic as well as intestinal metaplastic single-gland samples. In conclusion, the present data on tumor and corresponding intestinal metaplastic and nonmetaplastic glands suggest that genetic alterations already occur within the surrounding of the noncancerous mucosa.

Serrated adenoma of the colorectum undergoes a proliferation versus differentiation process: new conceptual interpretation of morphogenesis.

OBJECTIVE: Serrated adenoma (SA) consists of glands both with intraluminal projection of tall columnar cells, which resemble the terminally differentiated cells in the surface epithelium, and with concave short cells, which resemble progenitor crypt cells of the colon. The aim of this study was to clarify the relationship between the serrated architecture and proliferation/differentiation process in SAs. METHODS: The expressions of both terminally differentiated markers, such as p21, cytokeratin 20 and carbonic anhydrase I, and progenitor/proliferative markers, such as beta-catenin, CD44 and Ki-67, were immunohistochemically examined in 43 SAs and 20 tubular adenomas. RESULTS: P21-positive cells were more abundant in SAs than in tubular adenomas. Cytokeratin 20 and carbonic anhydrase I expressions were confined to the tall cells, while nuclear beta-catenin and CD44 were expressed in the short cells in SAs. The Ki-67 labeling indices were significantly lower in tall cells than in short ones. CONCLUSIONS: SAs might undergo both proliferation and terminal differentiation, which is associated with unique serrated configuration.

Novel approach for detecting global epigenetic alterations associated with tumor cell aneuploidy.

Although aneuploidy is commonly observed in human cancers, the molecular mechanism underlying aneuploidization remains unclear. We used multiploid cancer model that had diploid and aneuploid cancer cells within the same cancerous tissue and attempted to detect specific epigenetic alterations associated with tumor cell aneuploidy. Thirty-four multiploid colorectal cancers were subjected to crypt isolation and cell sorting, and paired diploid and aneuploid cancer cells were separated from each cancerous tissue. A methylated CpG island amplification provided a considerable number of CpG sequences that showed different methylation status between the above 2 cell populations. BLAST homology search revealed 24 different candidates (11 hypermethylated and 13 hypomethylated) from these sequences. The putative promoter sequence of the SALL4 (sal-like 4, a human homolog to Drosophila spalt) gene was particularly more frequently hypermethylated in aneuploid cells (62%) than diploid ones (35%) in the 34 multiploid cancers. Moreover, such hypermethylation occurred more often in aneuploid cancers (8 of 16, 50%) than diploid cancers (3 of 18, 17%). In combination with demethylation study on cultured cells, these results implied a possible association between epigenetic silencing of SALL4 and tumor cell aneuploidy. SALL4 may be one of important key players that act as "caretakers" for chromosomal stability. Our new approach is a powerful tool for the global identification of such key players.

Analysis of molecular alterations in left- and right-sided colorectal carcinomas reveals distinct pathways of carcinogenesis: proposal for new molecular profile of colorectal carcinomas.

To clarify distinct genetic profiles of colorectal cancers based on tumor location (left- and right-sided), we evaluated the status of loss of heterozygosity (LOH), CpG islands methylation phenotype (CIMP), microsatellite instability (MSI), and mutations of p53, Ki-ras, and APC genes in 119 colorectal cancers. Statuses of LOH (at 5q, 8p, 17p, 18q, and 22q), MSI, and CIMP (MINT1, MINT2, MINT31, MLH-1, MGMT, p14, p16, and RASSF1A) were determined using microsatellite polymerase chain reaction and methylation-specific polymerase chain reaction coupled with a crypt isolation method, respectively. In addition, mutations of p53, Ki-ras, and APC genes were also examined. LOH, MSI, and CIMP status allowed us to classify samples into two groups: low or negative and high or positive. Whereas the frequency of p53 mutations in the LOH-high status was significantly higher in left-sided cancers than in right-sided cancers, CIMP-high in the LOH-high status and MSI-positive status were more frequently found in right-sided cancers compared with left-sided cancers. Finally, location-specific methylated loci were seen in colorectal cancers: type I (dominant in right-sided cancer) and type II (common in both segments of cancer). Our data confirm that distinct molecular pathways to colorectal cancer dominate in the left and right sides of the bowel.

Clinicopathological significance of loss of heterozygosity in intestinal- and solid-type gastric carcinomas: a comprehensive study using the crypt isolation technique.

The clinicopathological significance of loss of heterozygosity (LOH) in gastric carcinoma remains poorly understood. We and other researchers have previously demonstrated that LOH is fairly common in intestinal- and solid-type gastric carcinomas, but rare in diffuse-type tumors. In this study, we investigated the relationship between clinicopathological variables and LOH status in intestinal- and solid-type gastric carcinomas. The crypt isolation technique was utilized to analyze LOH at 1p36, 3p14, 4p15, 5q21-22, 8p11-12, 9p21, 13q22, 17p13.1 18q21 and 22q13.31 in 113 intestinal- and solid-type gastric carcinomas using a polymerase chain reaction assay. Immunostaining with D2-40 and Elastica van Gieson staining were used to detect lymphatic invasion and vessel invasion, respectively. High LOH rates (49-71%) were observed in all chromosomal regions tested. 1p36 loss was significantly associated with advanced tumors and lymph node metastasis. 8p11-12 loss was significantly associated with lymph node metastasis, lymphatic invasion, and vessel invasion. 17p13.1 (TP53) loss was significantly associated with vessel invasion. 22q13.31 loss was significantly associated with advanced tumors, lymph node metastasis, lymphatic invasion, vessel invasion and late TNM stage. No significant associations were observed between LOH at other chromosomal regions and aggressive behaviors. In addition, significantly higher LOH rates at 1p36, 9p21, 18q21 and 22q13.31 were observed in cardiac tumors compared with noncardiac tumors. These results suggest that in intestinal- and solid-type gastric carcinomas, LOH on 3p14, 4p15, 5q21-22, 9p21, 13q22 and 18q21 is associated with carcinogenesis, while LOH on 1p36, 8p11-12, 17p31.1 and 22q13.31 is associated with tumor progression.

Analysis of SMAD4/DPC4 gene alterations in multiploid colorectal carcinomas.

BACKGROUND: Although recent animal studies have shown that SMAD4/DPC4 gene alterations are essential for late-stage intestinal tumorigenesis, the role of SMAD4/DPC4 gene alterations in primary human colorectal carcinomas is not fully understood. Therefore, we attempted to clarify the role of the SMAD4/DPC4 gene during tumor progression of colorectal carcinoma. METHODS: Differences in allelic imbalance (AI) and mutations of the SMAD4/DPC4 gene between diploid and aneuploid populations were analyzed for 30 sporadic DNA multiploid colorectal carcinomas (used as a tumor progression model and defined as the coexistence of diploid and aneuploid cells within the same tumor). The crypt isolation technique was coupled with DNA cytometric sorting and a polymerase chain reaction assay. In addition, hypermethylation of the promoter region was examined to clarify whether inactivation of gene expression occurred. RESULTS: Although a SMAD4/DPC4 gene AI was detected in only 5 of 27 informative diploid populations, 25 of 27 aneuploid populations had a SMAD4/DPC4 gene AI. Mutation of the SMAD4/DPC4 gene was detected in only one aneuploid population of multiploid colorectal carcinomas, but not in the corresponding diploid population. In total, 20 available multiploid carcinomas were selected for methylation analysis, and no evidence of hypermethylation of the promoter region was found. CONCLUSIONS: We suggest that, although mutation of the SMAD4/DPC4 gene and hypermethylation of the promoter region are infrequent events in colorectal tumorigenesis, AI at the SMAD4/DPC4 gene locus may play a key role in the progression of colorectal carcinomas.

Analysis of genetic alterations associated with DNA diploidy, aneuploidy and multiploidy in gastric cancers.

OBJECTIVE: Recent studies have shown a close association between DNA ploidy status (diploidy, aneuploidy and multiploidy) identified by the crypt isolation technique and specific genetic alterations in colorectal carcinomas. However, such an association has not been elucidated for gastric tumors, even though they share common genetic features with colorectal carcinomas. In the present study, we established an association between DNA ploidy status and genetic alterations in gastric cancer. METHOD: The DNA ploidy status of gastric tumors was classified as diploid, aneuploid or multiploid using the crypt isolation technique, which allows isolation of pure tumor crypt from tumor tissue. Crypt isolation combined with DNA cytometric sorting, polymerase chain reaction assay using 26 microsatellite markers and direct sequencing of the p53 gene were used to detect allelic imbalances [loss of heterozygosity (LOH) or allelic loss], microsatellite imbalance (MSI) and mutation of p53 in 54 gastric cancers (13 diploid, 12 aneuploid, 29 multiploid). RESULT: Diploid tumors showed few genetic alterations, including allelic imbalances and p53 mutations. In contrast, aneuploid tumors and multiploid tumors (in particular, aneuploid populations of multiploid tumors) exhibited multiple genetic alterations, including allelic imbalances and p53 mutations. In addition, the frequencies of genetic alterations observed in the corresponding diploid fractions of multiploid tumors were relatively higher than in diploid tumors. MSI was commonly observed in diploid, aneuploid and multiploid carcinomas. CONCLUSIONS: The present results indicate that in gastric carcinomas, diploid tumors are generally non-LOH and MSI, whereas aneuploid and multiploid tumors are associated with LOH and MSI, suggesting that the genetic profile of these carcinomas is dependent on the tumor's ploidy status.

Analysis of allelic imbalances at multiple cancer-related chromosomal loci and microsatellite instability within the same tumor using a single tumor gland from colorectal carcinomas.

Genetic changes related to colorectal carcinomas are accumulated in individual tumor glands during disease progression. Microsatellite allelic analysis of individual tumor glands from 30 colorectal carcinomas using a polymerase chain reaction (PCR) assay coupled with crypt isolation was used to detect intratumoral genetic heterogeneity, the sequence of allelic imbalances (AIs) and the microsatellite instability status of single tumor glands during neoplastic progression. In addition, the CpG islands methylated phenotype (CIMP) status was examined using a methylation-specific PCR method. The specimens were divided into 2 groups: a pooled gland sample, which was composed of more than 50 tumor glands, and a single tumor gland sample. The latter consisted of 10 single tumor glands, which were obtained from the same tumor separately. Most colorectal carcinomas (27 of 30 tumors) examined were heterogeneous for at least one genetic alteration, with from 2 to 7 genotypically different subclones detected per tumor. In 12 of the 27 heterogeneous tumors, it was possible to define the order of genetic alterations during the tumor progression. By analyzing multiple single tumor glands within the same tumor, we found that various subclonal expansions were seen within the same tumors. Finally, the AI pattern of single tumor glands was not correlated with CIMP status. Most carcinomas appeared to have a heterogeneous composition. This may have resulted from the successful progression of one clone that had different AIs in many chromosomal regions. This suggests that knowledge of the different genotypes of multiple single tumor glands may help clarify the process of tumor progression.

Analysis of microsatellite alterations in gastric carcinoma using the crypt isolation technique.

The crypt isolation technique was used to analyse loss of heterozygosity (LOH) and microsatellite instability (MSI) in gastric carcinomas (36 intestinal type, 17 solid type, and 23 diffuse type) using a polymerase chain reaction assay. Increased LOH frequencies and fractional allelic losses (FAL) were observed in samples prepared using the crypt isolation technique compared with those isolated by the conventional method. A significant increase in LOH was found at several chromosomal loci, and significant differences in FAL were found in patients with intestinal- and solid-type tumours. There was no difference in the frequency of MSI using either technique. In samples prepared by the crypt isolation technique, significant allelic losses (> or =50%) were observed at most loci tested in intestinal- and solid-type tumours, but not in diffuse-type tumours. Significant losses of some of these loci are novel findings for gastric cancer. FAL values were significantly higher in intestinal- and solid-type tumours than in diffuse-type tumours. MSI-high was observed in intestinal- (17%) and solid-type (12%) tumours. The results suggest that the crypt isolation technique is useful for accurate allelic loss analysis in gastric carcinoma and that LOH and MSI are more common in intestinal- and solid-type tumours than in diffuse-type tumors.

Application of the crypt isolation technique to the flow cytometric analysis of DNA content in gastric carcinoma.

An inevitable limitation of conventional flow cytometric analysis of gastric cancer DNA content is that the preparations of tumor cell nuclei are contaminated with stromal cell nuclei. Using the crypt isolation technique, we separated tumor tissues from stromal tissues and analyzed the DNA content in samples of pure gastric cancer cells (64 intestinal-type and 46 diffuse-type) by flow cytometry. Morphologically, crypts from well-differentiated and moderately differentiated adenocarcinomas usually showed large tube-like or sheet structures, whereas tumor tissues isolated from poorly differentiated adenocarcinomas usually exhibited small tumor cell clumps or clusters of varying sizes. Tumor ploidy was divided into diploid, aneuploid, and multiploid subgroups. Aneuploidy and multiploidy were observed in 12% (13 of 110) and 64% (71 of 110) of gastric cancers, respectively. A high frequency of DNA aneuploidy or multiploidy was associated with intestinal-type tumors, but not with any of the other clinicopathologic variables tested. In contrast, high S-phase fraction values demonstrated a close association with tumors with abnormal ploidy, advanced stage, intestinal type, and late TNM stage. Our results suggest that S-phase fraction may be a more useful indicator of aggressive behavior in gastric cancers than DNA aneuploidy. To our knowledge, the present study is the first to report flow cytometric DNA content in a large number of gastric cancer samples obtained using the crypt isolation technique.

Analysis of mucin, p53 protein and Ki-67 expressions in gastric differentiated-type intramucosal neoplastic lesions obtained from endoscopic mucosal resection samples: a proposal for a new classification of intramucosal neoplastic lesions based on nuclear atypia.

There are differing views between Western and Japanese pathologists on the use of histological criteria to classify gastrointestinal tumors. It is therefore a priority to create a new histological classification of the stomach in order to resolve the confusion. Expression patterns were examined of mucin (MUC2, CD10, MUC5AC, pyloric gland-type mucin), p53 protein, and Ki-67 in tumor cells according to the following new classification system for differentiated-type intramucosal neoplastic lesions of the stomach, based on nuclear atypia: borderline neoplasia (adenoma (including dysplasia), indefinite tumor of adenoma or low-grade cancer, and low-grade cancer) and definite carcinoma (intermediate cancer, and high-grade cancer). The resulting grades were: adenoma, 23; indefinite tumor for adenoma or low-grade cancer, 6; low-grade cancer, 28; intermediate cancer, 48; high-grade cancer, 20. While the frequency of intestinal-type borderline neoplasias was higher than that of definite carcinomas, the mixed-type of definite carcinomas occurred with higher frequency than borderline neoplasias. The p53 protein overexpression and the Ki-67-positive rate increased with an increase in the grade assigned according to the new classification. The correlated expression levels of p53 protein, Ki-67, and various mucins, support the conclusion that this classification of intramucosal neoplastic lesions is useful for obtaining a consensus diagnosis of gastric intramucosal neoplasia between pathologists and gastrointestinal clinicians.

Adenoma, adenocarcinoma and mixed carcinoid-adenocarcinoma arising in a small lesion of the colon.

A unique tumor measuring 8 x 8 x 5 mm and composed of adenoma, adenocarcinoma and mixed carcinoid-adenocarcinoma arising in the ascending colon is reported. The mixed carcinoid-adenocarcinoma, in which adenocarcinomatous and carcinoid components intermingled, originated in the mucosa, penetrated the muscularis mucosa and extended into the submucosa. Immunohistochemically, carcinoid cells were positive for neuroendocrine markers and adenocarcinoma cells were intracytoplasmicly positive for carcinoembryonic antigen. Ultrastructurally, membrane-bound electron dense granules varying in shape, size and electron density were detected in the cytoplasm of carcinoid cells. No mutations of p53 and k-ras genes were detected in adenomatous, adenocarcinomatous or mixed carcinoid-adenocarcinoma components. The morphological appearances of the present case strongly suggests the histogenesis of this tumor in an adenoma-adenocarcinoma-carcinoid tumor sequence.