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Background: The basal pattern of p53 expression, defined as its immunoreactivity confined to the basal half of the glands, is associated with early neoplastic lesions in ulcerative colitis (UC). However, their clinical utility of this finding is limited by the use of "visual estimation" (approximate immunoreactivity on the basis of scanning the stained slide, without formal counting). This study was designed to analyze the basal pattern of p53 using computer-assisted cytometry and to identify the optimal cutoff value for discriminating between UC-associated early-stage neoplasia and regenerative atypia., Methods: The specimens were obtained from eight UC patients undergoing colectomy and were classified according to the criteria by the Research Committee of Inflammatory Bowel Disease of the Ministry of Health and Welfare in Japan. Patients with classes UC-IIa (indefinite for dysplasia, probably regenerative), UC-IIb (indefinite for dysplasia, probably dysplastic), and UC-III (definitive dysplasia) were enrolled in the study. Based on the percentage of immunoreactive cells in the basal half of the crypt with visual estimation, basal positivity of p53 was classified into three categories: grade 1 (1 - 9%), grade 2 (10 - 19%), and grade 3 (≥ 20%). Next, crypts classified as grade 3 by visual estimation were analyzed by computer-assisted image analysis., Results: Using visual estimation, grade-3 p53 basal positivity was observed in 46.0% of UC-IIa crypts (128 of 278), 61.9% of UC-IIb crypts (39 of 63), and 94.2% of UC-III crypts (81 of 86). Using image analysis, the median p53 basal positivities were 30.3% in UC-IIa, 52.3% in UC-IIb, and 65.4% in UC-III (P ≤ 0.002). A receiver operating characteristics curve was generated to determine the method's diagnostic utility in differentiating UC-IIa from UC-III. In this cohort, the sensitivity was 0.78; the specificity was 0.98; the negative predictive value was 87.4%; the positive predictive value was 95.5%, and the accuracy was 90.2% with a cutoff value for p53 basal positivity of 46.1%., Conclusions: Our findings indicate that assessing p53 basal positivity by image analysis with an optimal threshold represents an alternative to visual estimation for the accurate diagnosis of UC-associated early-stage neoplasia., Virtual Slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3588120501252608.

Aims: Recently, several morphological variants of traditional serrated adenoma (TSA) of the colorectum have been recognised, and mucin‐rich TSA (MR‐TSA) and serrated tubulovillous adenoma (S‐TVA) were introduced as distinct morphological variants separate from conventional TSA (C‐TSA). This aim of this study was to elucidate the immunohistochemical and genetic characteristics of MR‐TSAs. Methods and results: We performed immunostaining for cytokeratins (CKs) (e.g. CK7 and CK20), mucins (e.g. MUC2, MUC5AC, MUC6, and CD10), β‐catenin, and MLH1, and direct sequencing of BRAF/KRAS, in 32 MR‐TSAs, 35 C‐TSAs, and 23 S‐TVAs. Immunohistochemically, all studied cases were positive for CK20, whereas few cases were positive for CK7, with no significant differences between the three groups. Regarding mucin‐phenotypic expression, all cases were positive for MUC2 but negative for MUC6 and CD10. MUC5AC positivity was found significantly more frequently in MR‐TSAs (53%) than in C‐TSAs (26%; P = 0.026). Nuclear β‐catenin expression in MR‐TSAs was significantly less frequent than in S‐TVAs (P = 0.002). MLH1 nuclear staining was retained in all cases. Genetically, MR‐TSAs (75%) more frequently harboured BRAF mutation than C‐TSAs (49%; P = 0.044) or S‐TVAs (4%; P < 0.001), whereas only two cases (6%) of MR‐TSA harboured a KRAS mutation, a frequency that was significantly lower than that in C‐TSAs (26%; P = 0.047) or S‐TVAs (57%; P < 0.001). Conclusions: MR‐TSAs more frequently harboured BRAF mutations than C‐TSAs, and had distinct immunohistochemical characteristics. Our findings indicated that MR‐TSAs could be important precursors of BRAF‐mutated, microsatellite‐stable subtypes of colorectal carcinoma. [ABSTRACT FROM AUTHOR]

Aims Intraductal papillary mucinous neoplasms ( IPMNs) differentiate in several histological directions, which are related to their clinical behaviour. Differentiation of IPMNs to the gastric foveolar epithelium/pyloric gland ( PG) is well known. However, no study has been conducted regarding fundic gland ( FG) differentiation. The aim of this study was to determine the frequency of FG differentiation and its relationship with the clinicopathological features of IPMNs, by studying 48 surgically resected IPMN cases consisting of 17 gastric IPMNs, 15 intestinal IPMNs, 10 pancreatobiliary IPMNs, and six oncocytic IPMNs. Methods and results Clinicopathological data, including histological tumour grade, immunohistochemical data for mucins ( MUCs), pepsinogen I, pepsinogen II, and H,K- ATPase, and GNAS/ KRAS status, were analysed. Pepsinogen I and H,K- ATPase were used to assess FG differentiation, and pepsinogen II and MUC6 were used to identify the equivalent cell type of the normal FG. Reverse transcription polymerase chain reaction ( RT- PCR) for PGA5/ PGC (pepsinogen I and pepsinogen II mRNA, respectively) and quantitative real-time RT- PCR ( qRT- PCR) for PGA5 were performed to confirm the immunohistochemistry results. Pepsinogen I expression was detected in 12.5% (6/48) of total IPMNs, of which 66.7% (4/6) of oncocytic IPMNs and 20.0% (2/10) of pancreatobiliary IPMNs were pepsinogen I-positive. No H,K- ATPase-positive cases were detected. Three oncocytic IPMNs with pepsinogen I expression showed similar histology to normal FG. RT- PCR and qRT- PCR confirmed the immunohistochemical results. All IPMNs with FG differentiation were of the oncocytic or pancreatobiliary subtype, were of histologically high grade, and were without GNAS mutation. Conclusions The differentiation of IPMNs to gastric FG is related to oncocytic and pancreatobiliary subtypes, and to high grade. This is the first report to describe differentiation of IPMNs to the FG, and to reveal its relationship with the clinicopathological features of IPMNs. [ABSTRACT FROM AUTHOR]

Background: Gastric adenocarcinoma with enteroblastic differentiation (GAED) has been recognized as a variant of alpha-fetoprotein (AFP)-producing gastric carcinoma, although its clinicopathologic and immunohistochemical features have not been fully elucidated. Methods: To elucidate the clinicopathologic and immunohistochemical features of GAED, we analyzed 29 cases of GAED, including ten early and 19 advanced lesions, and compared these cases with 100 cases of conventional gastric adenocarcinoma (CGA). Immunohistochemistry for AFP, glypican 3, SALL4, and p53 was performed, and the phenotypic expression of the tumors was evaluated by immunostaining with antibodies against MUC5AC, MUC6, MUC2, CD10, and caudal-type homeobox 2 (CDX2). Results: Lymphatic and venous invasion was more frequent in GAED (76 and 72 %) than in CGA (41 and 31 %; P ≤ 0.001). Lymph node metastasis was more frequently observed in GAED (69 %) than in CGA (38 %; P = 0.005), as were synchronous or metachronous liver metastases (GAED, 31 %; CGA, 6 %; P ≤ 0.001). Immunohistochemically, all GAED were positive for at least one of three enteroblastic linage markers (AFP, glypican 3, and SALL4). Glypican 3 was the most sensitive marker (83 %) for GAED, followed by SALL4 (72 %) and AFP (45 %), whereas no CGA was positive. Furthermore, the rate of positive p53 staining was 59 % in GAED. Regarding the mucin phenotype, CD10 and CDX2 were diffusely or focally expressed in all GAED cases. Invasive areas with hepatoid or enteroblastic differentiation were negative for CD10 and CDX2. Conclusions: Clinicopathologic features of GAED differ from those of CGA. GAED shows aggressive biological behavior, and is characteristically immunoreactive to AFP, glypican 3, or SALL4. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the expression pattern of manganese superoxide dismutase ( MnSOD) in relation to inflammatory factors in ulcerative colitis ( UC) and characterize this enzyme as a newly identified biomarker potentially linked to disease pathogenesis of UC. MnSOD expression was analyzed immunohistochemically in 48 formalin-fixed and paraffin-embedded specimens from patients with UC who had undergone endoscopical biopsy. MnSOD expression was observed in vascular endothelium, macrophages, and polymorphonuclear leukocytes within lamina propria of inflamed mucosa. The patients who did not express MnSOD tended to have stabilization of symptoms, but accompanied with status of inflammation. The MnSOD expression pattern was strongly correlated with disease type. MnSOD was expressed in polymorphonuclear leukocytes of all disease types, but cases of chronically counting and exacerbation type had particularly high frequency of immunopositive cells. MnSOD expression in macrophages was frequently observed in cases of symptom remaining type. The cases with MnSOD expression in the vascular endothelium showed a tendency to express in relapse-remission and exacerbation of symptoms. Immunohistochemical evaluation for MnSOD expression may be useful for predicting disease severity and activity in patients with UC. [ABSTRACT FROM AUTHOR]

We reviewed the clinicopathological findings of eight cases of sessile serrated adenoma/polyps ( SSA/ Ps) with carcinoma, the largest diameter of which was 10 mm or less. All lesions were polyps located in the right side of the colon. Four lesions showed submucosal invasion and one lesion invaded the proper muscle layer. The depth of invasion, however, did not seem to be related to the carcinoma area size. Most carcinomas were well to moderately differentiated tubular adenocarcinomas focally showing some serrated appearances, and the predominant component of one carcinoma was a poorly differentiated medullary growth with inflammatory stroma. Rapid progression to invasive carcinoma from SSA/ P was suggested for the carcinoma with proper muscle invasion whereas one submucosally invasive carcinoma was considered to progress over 7 years. Immunohistochemically, it was suggested that with or without hMLH1 protein loss, alterations of p53 and/or Wnt signaling pathway can be involved in the cancerization through SSA/ Ps. The carcinomas irregularly imitated the mucin expression of the SSA/ Ps (positive for MUC5AC and MUC2, and MUC6 expression in crypt bases), which was lost with progression of the carcinomas. Analyses of small SSA/ P lesions with cancerization would facilitate the understanding of the mode of progression of SSA/ Ps and their early detection. [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate the diagnosis of desmoplastic reaction (DR) by immunostaining for a-smooth muscle actin (aSMA) and desmin, for predicting the depth of submucosal invasion in biopsy specimens of early colorectal carcinomas (CRCs). Thirty-eight cases of non-pedunculated early CRCs were included in this study. Positive for DR was defined as aSMA-positive and desmin-negative stroma in the CRC. The depth of submucosal invasion was measured in endoscopically or surgically resected specimens and the lesions were subsequently divided into two groups: Group A (carcinoma in situ/intramucosal carcinoma and submucosal invasive carcinoma with a depth <1000 µm) and Group B (submucosal invasion with a depth =1000 µm). Twenty-one cases were DR-positive and 17 were DR-negative. No statistical significance was found between the DR with regard to tumor size, location and histological type. All DR-positive cases belonged to Group B whereas 14 (82.4%) DR-negative lesions belonged to Group A (p < 0.001). The sensitivity, specificity, positive and negative predictive values and accuracy of DR positivity for diagnosis of Group B were 87.5%, 100%, 100%, 82.4% and 92.1%, respectively. Conclusively, detection of DR in biopsy specimens with ancillary immunohistochemistry (aSMA/desmin) would help in preoperative diagnosis for the depth of submucosal invasion of early CRC. [ABSTRACT FROM AUTHOR]

Abstract: INTRODUCTION: Low-grade myofibroblastic sarcoma (myofibrosarcoma) is described to be a distinct atypical myofibroblastic tumor often with fibromatosis-like features and predilection for head and neck. Low-grade myofibroblastic sarcoma of bone is extremely rare. PRESENTATION OF CASE: A 50-year-old woman was admitted to our hospital because she had experienced right knee pain for 2 years. Plain radiography showed a honeycombed lesion on the right distal femur, and computed tomography showed a bone tumor with cortex destruction invading the soft tissue. A biopsy specimen from the intraosseous lesion showed a hypocellular area of spindle cell proliferation with dense collagen deposition, which is reminiscent of a histological feature of desmoplastic fibroma. However, histological examination of the extraosseous lesion indicated a slightly hypercellular area containing scattered spindle-shaped atypical cells with enlarged nuclei, suggestive of low-grade sarcoma. Spindle-shaped atypical cells were immunohistochemically positive for SMA. A final diagnosis of low-grade myofibroiblastic sarcoma of the bone was made from a surgically resected specimen. DISCUSSION: The patient was alive and well with no evidence of disease at 15 months after the surgery without any additional therapy. CONCLUSION: Extensive sampling of a tumor may be necessary to determine the true nature of the tumor and to make an accurate diagnosis. [Copyright &y& Elsevier]

Summary: Basaloid squamous cell carcinoma of the esophagus is a rare variant of squamous cell carcinoma. We reviewed 878 cases of esophageal squamous cell carcinoma and detected 22 cases (3%) of basaloid squamous cell carcinoma. These tumors and stage-matched paired conventional squamous cell carcinomas were investigated for clinicopathologic features and immunoreactivity of cytokeratin subtypes, p53, B-cell lymphoma 2 (bcl-2), β-catenin, and epidermal growth factor receptor. Molecular aberrations in p53, CTNNB1 (the gene encoding β-catenin), and epidermal growth factor receptor (EGFR) were also determined. Patients with basaloid squamous cell carcinomas demonstrated a 5-year survival rate of 42%, significantly worse than those with well-differentiated squamous cell carcinoma (P < .01). Histologically, solid nests with central necrosis and a cribriform pattern were identified in almost all (≥95%) cases, and ductal differentiation was less frequent (45%) but associated with significantly better survival (P < .05). Compared with conventional squamous cell carcinomas, the basaloid squamous cell carcinomas were less immunoreactive for cytokeratin 14, cytokeratin 903, and membranous β-catenin (P < .01-.001) but more reactive for bcl-2, nuclear β-catenin, epidermal growth factor receptor, and Ki-67 (P < .05-.001). Direct sequencing showed mutations of p53 (36%), EGFR (14%), but not CTNNB1; fluorescent in situ hybridization detected amplification of the epidermal growth factor receptor gene (22%). In basaloid squamous cell carcinomas, low-level expression of cytokeratin 14/cytokeratin 903 and mutations of p53 and EGFR had a significant influence on worse survival (P < .05-.001). We conclude that the esophageal basaloid squamous cell carcinoma, a neoplasm with particularly aggressive biologic behavior, should be differentiated from conventional squamous cell carcinomas. In this context, immunohistochemical assessment of several markers might provide a useful adjunct diagnostic tool. Aberrations of p53 and epidermal growth factor receptor genes are possibly involved in progression of esophageal basaloid squamous cell carcinoma. [Copyright &y& Elsevier]

Aims: Despite the established prognostic relevance of tumour budding in colorectal cancer, the reproducibility of the methods reported for its assessment has not yet been determined, limiting its use and reporting in routine pathology practice. Methods arid results: A morphometric system within telepathology was devised to evaluate the reproducibility of the various methods published for the assessment of tumour budding in colorectal cancer. Five methods were selected to evaluate the diagnostic reproducibility among 10 investigators, using haematoxylin and eosin (H&E) and AE1-3 cytokeratin-immunostained, whole-slide digital scans from 50 pT1-pT4 colorectal cancers. The overall interobserver agreement was fair for all methods, and increased to moderate for pT1 cancers. The intraobserver agreement was also fair for all methods and moderate for pT1 cancers. Agreement was dependent on the participants' experience with tumour budding reporting and performance time. Cytokeratin immunohistochemistry detected a higher percentage of tumour budding-positive cases with all methods compared to H&E-stained slides, but did not influence agreement levels. Conclusions: An overall fair level of diagnostic agreement for tumour budding in colorectal cancer was demonstrated, which was significantly higher in early cancer and among experienced gastrointestinal pathologists. Cytokeratin immunostaining facilitated detection of budding cancer cells, but did not result in improved interobserver agreement. [ABSTRACT FROM AUTHOR]

Summary: Gastrointestinal stromal tumors feature a wide spectrum of biologic behavior, ranging from benign to extremely malignant. To determine the role of p16INK4a alteration in progression of gastrointestinal stromal tumors of the stomach, we have investigated protein expression and gene methylation in correlation with clinicopathologic factors and survival. In addition to immunohistochemical analysis of p16INK4a in a series of 95 cases, real-time quantitative methylation specific polymerase chain reaction for p16INK4a and immunostaining for cyclin D1, cyclin E, pRb, DP-1, E2F-1, and Ki-67 were also evaluated in randomly selected samples. The p16INK4a labeling indices ranged from 0% to 74% (median, 21%), demonstrating a significant inverse correlation with size (P = .046). On univariate (P = .003) and multivariate (P = .067) analyses, loss of p16INK4a expression increased the likelihood of a poor tumor-related survival. In addition, size (P = .036) and the mitotic index (P = .005) had independent prognostic influence. The p16INK4a methylation index, which ranged from 0% to 100% (median, 17%), was significantly higher in larger tumors (P < .001) and in high-risk category lesions (P = .001) and inversely correlated with protein expression. Hierarchical cluster analysis based on expression of p16INK4a network members identified 2 clusters in 27 randomly selected tumor samples, containing 11 and 16 tumors each. Former cluster samples demonstrated higher risk category (P = .022), higher p16INK4a methylation (P < .001), and more reduced pRb expression (P < .018). In addition, p16INK4a network members clustered into 2 groups: (1) showing down-regulated p16INK4a protein and up-regulating of both cyclin D1 and DP-1 and (2) down-regulated pRb and up-regulated E2F-1. We conclude that p16INK4a alteration has an important role in progression of gastrointestinal stromal tumors of the stomach. Furthermore, the study provides a possible link between regulation of p16INK4a network members and gastrointestinal stromal tumors. [Copyright &y& Elsevier]

Summary: A 46-year-old man was admitted to the hospital with a recurrent giant-cell tumor of the distal femur. This was his fourth recurrence, and it had occurred 16 years after his last treatment. The resected recurrent tumor was histologically determined to be a conventional giant-cell tumor. However, a single lung metastatic lesion and local recurrence were noticed 6 months after the resection, both of which were surgically excised. The lung lesion was histologically determined to be an implantation of giant-cell tumor, whereas the local recurrent lesion contained a clearly separated fibrosarcomatous area within the conventional giant-cell tumor. Immunohistochemistry showed diffuse and strong p53 expression in the fibrosarcomatous area. Direct sequencing revealed a p53 mutation in the sarcomatous area and a recessive mutant signal in the conventional area. The lung lesion also contained the same p53 mutation. Identification of the p53 mutation may help in diagnosing potential malignant transformation of giant-cell tumor. [Copyright &y& Elsevier]

Granular cell tumors (GCT) are infrequently found in the gastrointestinal tract (GIT), and only four previous reports have described lesions occurring simultaneously in different sites. The present case of 11 GCT, located in the esophagus, stomach, colon and pericolic adipose tissue, occurred in a 50-year-old Japanese woman. All GCT appeared histologically benign and there was no sign of recurrence at 3 years after surgery. Immunohistochemical analysis and comparison between this case of multifocal GCT and six cases of solitary benign GCT of the GIT, which were taken from the files of the Department of Pathology at Kitasato University (1986–2000), demonstrated the follow-ing: (1) all diffusely expressed S-100, DCC and bcl-2, and (2) median labeling indices for Ki-67, cyclin D1, p53 (Pab1801), and p21WAF1/CIP1 of 4%, 24%, 1% and 28%, respectively, for the multifocal tumors, and 3.5%, 23%, 1% and 29%, respectively, for the solitary lesions, with no significant difference between the two groups. Thus, the expression of cyclin D1 and p21WAF1/CIP1 may be involved in the tumorigenesis of both types of GCT. The present case emphasizes the need to evaluate the entire GIT when a single GCT is identified. Multifocal lesions should be treated conservatively by local excision because, as with the solitary tumors, they exhibit a benign biological behavior, consistent with their low Ki-67 immunoreactivity. [ABSTRACT FROM AUTHOR]

In order to investigate cell kinetics and cell cycle regulator protein expression with reference to the growth pattern of early gastric carcinomas (EGCs), we evaluated a total of 240 EGCs with submucosal invasion clinicopathologically and 106 submucosal invasive lesions immunohistochemically. The incidence of lymph node metastasis was relatively high (36.4%) in the superficially spreading growth (SUP) type tumors whereas the penetrating growth (PEN) type had a low incidence (5.7%, P < 0.001) and correlated with submucosal tumor size. Ki67 labeling was lower in submucosal areas of the SUP-type tumors (median, 37.3%) than the PEN-type tumors (51.0%, P < 0.001). ssDNA labeling in the lamina propria, indicative of apoptotic activity, was higher in the SUP-type tumors (0.55%) than in PEN-type (0.30%, P < 0.01) lesions. The expression of cell cycle regulator p21WAF1/CIP1 was lower in the SUP-type tumors (lamina propria 15.6%, submucosa 2.6%) than in PEN-type tumors (lamina propria 26.5%, submucosa 4.4%, P < 0.05–0.001). In conclusion, differences in cell kinetics and p21WAF1/CIP1 expression might influence the growth pattern of EGCs. The SUP-type EGC, characterized by high apoptotic in the lamina propria and low proliferative activities in the submucosa, is associated with frequent lymph node metastasis, suggesting a strong correlation between tumor size in the submucosa and metastatic potential. [ABSTRACT FROM AUTHOR]

A case of an aggressive desmoid tumor in a patient with familial adenomatous polyposis is described. The lesion rapidly enlarged with compression of adjacent structures including the ureter and small bowel, and the patient died because of small bowel perforation and hydronephrosis 3 years after detection of small desmoid tumors at the time of a prophylactic coloproctectomy for a colon carcinoma. Immunohistochemically, proliferating cell nuclear antigen (PCNA), p21WAF1/CIP1 cathepsin D indices, but not the bcl-2 index, which were defined as the numbers of immunoreactive tumor cells per 1000 tumor cells, increased in line with tumor progression. The tumor did not show staining for collagen IV, but was characterized by intense staining for basic fibroblast growth factor (bFGF). Accordingly, tumor aggression was related to increases in both cell proliferation and protease activity, as well as an enhanced expression of bFGF. In addition, the desmoid tumor showed deregulation between PCNA and p21WAF1/CIP1 because the normal inverse relation between these two was not apparent. [ABSTRACT FROM AUTHOR]