Heterogeneity in liver histopathology is associated with GSK-3ß activity and mitochondrial dysfunction in end-stage diabetic rats on differential diets.

While liver histopathology is heterogeneous in diabetes, the underlying mechanisms remain unclear. We investigated whether glycemic variation resulting from differential diets can induce heterogeneity in diabetic liver and the underlying molecular mechanisms. We generated end-stage non-obese diabetic model rats by subtotal-pancreatectomy in male Sprague- Dawley rats and ad libitum diet for 7 weeks (n = 33). The rats were then divided into three groups, and fed a standard- or a low-protein diet (18 or 6 kcal%, respectively), for another 7 weeks: to maintain hyperglycemia, 11 rats were fed ad libitum (18AL group); to achieve euglycemia, 11 were calorierestricted (18R group), and 11 were both calorie- and proteinrestricted with the low-protein diet (6R group). Overnightfasted liver samples were collected after the differential diets together with sham-control (18S group), and histology and molecular changes were compared. Hyperglycemic-18AL showed glycogenic hepatopathy (GH) without steatosis, with the highest GSK-3ß inactivation because of Akt activation during hyperglycemia; mitochondrial function was not impaired, compared to the 18S group. Euglycemic-18R showed neither GH nor steatosis, with intermediate GSK-3ß activation and mitochondrial dysfunction. However, euglycemic-6R showed both GH and steatosis despite the highest GSK-3ß activity and no molecular evidence of increased lipogenesis or decreased ApoB expression, where mitochondrial dysfunction was highest among the groups. In conclusion, heterogeneous liver histopathology developed in end-stage non-obese diabetic rats as the glycemic levels varied with differential diets, in which protein content in the diets as well as glycemic levels differentially influenced GSK-3ß activity and mitochondrial function in insulin-deficient state. [BMB Reports 2020; 53(2): 100-105].

Diagnostic Limitation of Fine-Needle Aspiration (FNA) on Indeterminate Thyroid Nodules Can Be Partially Overcome by Preoperative Molecular Analysis: Assessment of RET/PTC1 Rearrangement in BRAF and RAS Wild-Type Routine Air-Dried FNA Specimens.

Molecular markers are helpful diagnostic tools, particularly for cytologically indeterminate thyroid nodules. Preoperative RET/PTC1 rearrangement analysis in BRAF and RAS wild-type indeterminate thyroid nodules would permit the formulation of an unambiguous surgical plan. Cycle threshold values according to the cell count for detection of the RET/PTC1 rearrangement by real-time reverse transcription-polymerase chain reaction (RT-PCR) using fresh and routine air-dried TPC1 cells were evaluated. The correlation of RET/PTC1 rearrangement between fine-needle aspiration (FNA) and paired formalin-fixed paraffin-embedded (FFPE) specimens was analyzed. RET/PTC1 rearrangements of 76 resected BRAF and RAS wild-type classical PTCs were also analyzed. Results of RT-PCR and the Nanostring were compared. When 100 fresh and air-dried TPC1 cells were used, expression of RET/PTC1 rearrangement was detectable after 35 and 33 PCR cycles, respectively. The results of RET/PTC1 rearrangement in 10 FNA and paired FFPE papillary thyroid carcinoma (PTC) specimens showed complete correlation. Twenty-nine (38.2%) of 76 BRAF and RAS wild-type classical PTCs had RET/PTC1 rearrangement. Comparison of RET/PTC1 rearrangement analysis between RT-PCR and the Nanostring showed moderate agreement with a κ value of 0.56 (p = 0.002). The RET/PTC1 rearrangement analysis by RT-PCR using routine air-dried FNA specimen was confirmed to be technically applicable. A significant proportion (38.2%) of the BRAF and RAS wild-type PTCs harbored RET/PTC1 rearrangements.

Molecular Profiling of Papillary Thyroid Carcinoma in Korea with a High Prevalence of BRAFV600E Mutation.

BACKGROUND: The BRAFV600E mutation in papillary thyroid carcinoma (PTC) is particularly prevalent in Korea, and a considerable number of wild-type BRAF PTCs harbor RAS mutations. In addition, subsets of other genetic alterations clearly exist, but their prevalence in the Korean population has not been well studied. Recent increased insight into noninvasive encapsulated follicular variant PTC has prompted endocrine pathologists to reclassify this entity as "noninvasive follicular thyroid neoplasm with papillary-like nuclear features" (NIFTP). This study analyzed the genetic alterations among the histologic variants of PTC, including NIFTP. METHODS: Mutations of the BRAF and RAS genes and rearrangement of the RET/PTC1, NTRK1, and ALK genes using 769 preoperative fine-needle aspiration specimens and resected PTCs were analyzed. RESULTS: Molecular alterations were found in 687 (89.3%) of 769 PTCs. BRAFV600E mutation (80.8%) was the most frequent alteration, followed by RAS mutation and RET/PTC1, NTRK1, and ALK rearrangements (5.6%, 2.1%, 0.4%, and 0%, respectively). The low prevalence of NTRK1 fusions and the absence of an ALK fusion detected in Korea may also be attributed to the higher prevalence of the BRAFV600E mutation. There were significant differences in the frequency of the genetic alterations among the histologic variants of PTC. The prevalence of NIFTP in PTC was 2.7%, and among the NIFTPs, 28.6% and 57.1% harbored BRAF and RAS mutations, respectively. Clinicopathologic factors and mutational profiles between NIFTP and encapsulated follicular variant PTC with capsular invasion group were not significantly different. CONCLUSIONS: Genetic alterations in PTC vary among its different histologic variants and seem to be different in each ethnic group.

Comparison Between Real-Time PCR and Pyrosequencing for Detection of BRAF V600E Mutation in Thyroid Fine-Needle Aspirates.

The BRAF V600E mutation test has proven diagnostic value in thyroid fine-needle aspiration. The real-time polymerase chain reaction (RT-PCR) has recently been introduced as a new method for BRAF mutation detection. We performed BRAF V600E detection in 126 cases of thyroid fine-needle aspiration, using RT-PCR and pyrosequencing. BRAF V600E mutation was detected in 78 (61.9%) of 126 cases by RT-PCR and in 74 (57.8%) by pyrosequencing. Of the 98 papillary thyroid carcinoma samples, the BRAF V600E mutation was identified in 72 by RT-PCR and in 70 by pyrosequencing (sensitivities of 71.6% and 71.4%, respectively). Among 28 benign nodules, 6 false-positive cases were detected by RT-PCR, whereas 4 false-positive cases were detected by pyrosequencing (specificities of 78.6% and 85.7%, respectively). When analyzing 104 cases after excluding equivocal samples, pyrosequencing had a marginally higher specificity than RT-PCR (100% vs. 78.3%, P=0.074). After modifying the cut-off criteria, the low RT-PCR specificity improved to a similar or a slightly lower specificity compared with that of pyrosequencing. In the titration assay mixing the mutant DNA with the wild-type DNA in varying proportions, RT-PCR was sensitive enough to detect the mutation in a mixture containing 0.001% mutant DNA, whereas the limit of detection was 10% for pyrosequencing. In conclusion, compared with pyrosequencing, RT-PCR was more sensitive, faster, and more convenient, but less specific, for detecting the BRAF V600E mutation. A readjustment or modification of the interpretation criteria may be necessary to reduce false-positive RT-PCR results and improve the specificity while maintaining the sensitivity.

Tannic acid inhibits EGFR/STAT1/3 and enhances p38/STAT1 signalling axis in breast cancer cells.

Tannic acid (TA), a naturally occurring polyphenol, is a potent anti-oxidant with anti-proliferative effects on multiple cancers. However, its ability to modulate gene-specific expression of tumour suppressor genes and oncogenes has not been assessed. This work investigates the mechanism of TA to regulate canonical and non-canonical STAT pathways to impose the gene-specific induction of G1-arrest and apoptosis. Regardless of the p53 status and membrane receptors, TA induced G1-arrest and apoptosis in breast cancer cells. Tannic acid distinctly modulated both canonical and non-canonical STAT pathways, each with a specific role in TA-induced anti-cancer effects. Tannic acid enhanced STAT1 ser727 phosphorylation via upstream serine kinase p38. This STAT1 ser727 phosphorylation enhanced the DNA-binding activity of STAT1 and in turn enhanced expression of p21Waf1/Cip1 . However, TA binds to EGF-R and inhibits the tyrosine phosphorylation of both STAT1 and STAT3. This inhibition leads to the inhibition of STAT3/BCL-2 DNA-binding activity. As a result, the expression and mitochondrial localization of BCl-2 are declined. This altered expression and localization of mitochondrial anti-pore factors resulted in the release of cytochrome c and the activation of intrinsic apoptosis cascade involving caspases. Taken together, our results suggest that TA modulates EGF-R/Jak2/STAT1/3 and P38/STAT1/p21Waf1/Cip1 pathways and induce G1-arrest and intrinsic apoptosis in breast carcinomas.

Analysis of predictability of F-18 fluorodeoxyglucose-PET/CT in the recurrence of papillary thyroid carcinoma.

Whether preoperative F-18 fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) can predict recurrence of papillary thyroid carcinoma (PTC) remains unclear. Herein, we evaluated the potential of primary tumor FDG avidity for the prediction of tumor recurrence in PTC patients. A total of 412 PTC patients (72 males, 340 females; age: 47.2 ± 12.2 years; range: 17-84 years) who underwent FDG-PET/CT prior to total thyroidectomy (n = 350), subtotal thyroidectomy (n = 2), or lobectomy (n = 60) from 2007 to 2011 were analyzed. The predictive ability for recurrence was investigated among various clinicopathological factors, BRAFV600E mutation, and preoperative FDG avidity of the primary tumor using Kaplan-Meier (univariate) and Cox proportional hazards regression (multivariate) analyses. Of the 412 patients, 19 (4.6%) experienced recurrence, which was confirmed either by pathology (n = 17) or high serum thyroglobulin level (n = 2), during a mean follow-up period of 43.9 ± 16.6 months. Of the 412 patients, 237 (57.5%) had FDG-avid tumors (maximum standardized uptake value, 7.1 ± 7.0; range: 1.6-50.5). Kaplan-Meier analysis revealed that tumor size (P = 0.0054), FDG avidity of the tumor (P = 0.0049), extrathyroidal extension (P = 0.0212), and lymph node (LN) stage (P < 0.0001) were significant predictors for recurrence. However, only LN stage remained a significant predictor in the multivariate analysis (P < 0.0001). Patients with FDG-avid tumors had higher LN stage (P < 0.0001), larger tumor size (P < 0.0001), and more frequent extrathyroidal extension (P < 0.0001). In conclusion, FDG avidity of the primary tumor in preoperative FDG-PET/CT could not predict the recurrence of PTC. LN stage was the only identified predictor of PTC recurrence.

Mixed Carcinoma as an Independent Prognostic Factor in Submucosal Invasive Gastric Carcinoma.

Mixed carcinoma shows a mixture of glandular and signet ring/poorly cohesive cellular histological components and the prognostic significance of each component is not fully understood. This study aimed to investigate the significance of the poorly cohesive cellular histological component as a risk factor for lymph node metastasis and to examine the diagnostic reliability of endoscopic biopsy. Clinicopathologic characteristics of 202 patients who underwent submucosal invasive gastric carcinoma resection with lymph node dissection in 2005-2012 were reviewed. Mixed carcinoma accounted for 27.2% (56/202) of cases. The overall prevalence of lymph node metastasis was 17.3% (35/202). Lymphatic invasion (P < 0.001), family history of carcinoma (P = 0.025), tumor size (P = 0.004), Lauren classification (P = 0.042), and presence of any poorly cohesive cellular histological component (P = 0.021) positively correlated with the lymph node metastasis rate on univariate analysis. Multivariate analyses revealed lymphatic invasion, family history of any carcinoma, and the presence of any poorly cohesive cellular histological component to be significant and independent factors related to lymph node metastasis. Review of preoperative biopsy slides showed that preoperative biopsy demonstrated a sensitivity of 63.6% and a specificity of 100% in detecting the presence of the poorly cohesive cellular histological component, compared with gastrectomy specimens. The presence of any poorly cohesive cellular histological component was an independent risk factor associated with lymph node metastasis in submucosal invasive gastric carcinoma. Endoscopic biopsy had limited value in predicting the presence and proportion of the poorly cohesive cellular histologic component due to the heterogeneity of mixed carcinoma.

Prognostic Significance of TERT Promoter Mutations in Papillary Thyroid Carcinomas in a BRAF(V600E) Mutation-Prevalent Population.

BACKGROUND: The role of telomerase reverse transcriptase (TERT) promoter mutations in differentiated thyroid cancer has been well established. These mutations have a significantly higher prevalence in aggressive thyroid tumors, including widely invasive oncocytic carcinomas, poorly differentiated carcinomas, and anaplastic thyroid carcinomas. Interestingly, in some studies, TERT mutations were found to be more common in tumors with a BRAF(V600E) mutation. However, mutational analysis of TERT promoter mutations in thyroid tumors has not been previously performed for patients in Korea, where the BRAF(V600E) mutation in papillary thyroid carcinoma (PTC) is particularly prevalent. This study analyzed TERT promoter mutations in various thyroid tumors and examined their relationship with clinicopathologic factors and the BRAF(V600E) mutation in PTC cases. METHODS: Using 242 preoperative fine-needle aspiration biopsy specimens (including 207 PTCs) with confirmed histopathological diagnosis of the biopsied thyroid nodules, the TERT promoter status (C228T and C250T) was analyzed, and the relationship with clinicopathologic factors and the BRAF(V600E) mutation in PTC cases was examined. RESULTS: Of 242 patients, 14.5% (30/207), 26.7% (4/15), 50% (1/2), and 60% (2/5) of PTCs, follicular thyroid carcinomas, poorly differentiated carcinomas, and anaplastic thyroid carcinomas harbored a TERT(C228T) mutation, respectively. The TERT(C228T) mutation was associated with recurrence (p = 0.03). However, no association with other clinicopathologic factors in PTC was found. Coexistence of TERT(C228T) and BRAF(V600E) mutations was found in 13.0% of PTCs and was significantly associated with older age and advanced stage compared with the group negative for either mutation. The TERT(C228T) mutation status was an independent prognostic factor for recurrence-free survival (hazard ratio = 3.08 [confidence interval 1.042-9.079]; p = 0.042) in patients with PTC in multivariate analysis. CONCLUSIONS: Identification of TERT promoter mutations in preoperative fine-needle aspiration biopsy specimens may help in better characterizing the prognosis and triaging thyroid cancer patients for appropriate treatment.

Epigenetic alteration of imprinted genes during neural differentiation of germline-derived pluripotent stem cells.

Spermatogonial stem cells (SSCs), which are unipotent stem cells in the testes that give rise to sperm, can be converted into germline-derived pluripotent stem (gPS) by self-induction. The androgenetic imprinting pattern of SSCs is maintained even after their reprogramming into gPS cells. In this study, we used an in vitro neural differentiation model to investigate whether the imprinting patterns are maintained or altered during differentiation. The androgenetic patterns of H19, Snrpn, and Mest were maintained even after differentiation of gPS cells into NSCs (gPS-NSCs), whereas the fully unmethylated status of Ndn in SSCs was altered to somatic patterns in gPS cells and gPS-NSCs. Thus, our study demonstrates epigenetic alteration of genomic imprinting during the induction of pluripotency in SSCs and neural differentiation, suggesting that gPS-NSCs can be a useful model to study the roles of imprinted genes in brain development and human neurodevelopmental disorders.

DNA degradation in liquid-based cytology and its comparison with conventional smear.

BACKGROUND: In fine needle aspiration biopsy (FNAB) of thyroid nodules, LBC is adopted in most of the hospitals and clinics in Korea for its convenience. BRAF mutation test has been introduced as an important ancillary test, but its applicability has not been completely proven with LBC samples. METHODS: Five aspirates from thyroidectomy specimens were simultaneously processed into LBC and CS slides, in which BRAF mutation tests were performed using three primer sets with PCR products of 72, 164, and 226 base pairs (bp) at 6, 9, and 12 months after processing. In addition, BRAF mutation tests were performed in nine clinical samples that had been prepared by LBC or CS and stored for 3-5 years after processing. RESULTS: At 9 months after processing, LBC failed to provide DNA of sufficient quality for PCR, whereas CS succeeded with primers for amplifying a 226 bp fragment. Furthermore, CS had successful amplification of DNA despite a delay of more than 1 year. The failure of DNA amplification in LBC was overcome by using primers to amplify shorter PCR products, suggesting that DNA degradation occurred in LBC. However, false positive or negative results were observed in primers for amplifying shorter size. The kind of preservative solutions used in LBC did not affect test results. CONCLUSION: LBC may have disadvantages in long-term DNA preservation because of its accelerated DNA degradation compared with alcohol-fixed CS. Using primers to amplify shorter size fragments might be helpful in mitigating loss of signal due to DNA degradation in LBC.

Radiologic and Pathologic Findings of a Follicular Variant of Papillary Thyroid Cancer with Extensive Stromal Fat: A Case Report.

Thyroid cancer may have small adipose structures detected by microscopy. However, there are no reports of thyroid cancer with gross fat evaluated by radiological methods. We reported a case of a 58-year-old woman with a fat containing thyroid mass. The mass was hyperechoic and ovoid in shape with a smooth margin on ultrasonography. On computed tomography, the mass had markedly low attenuation suggestive of fat, and fine reticular and thick septa-like structures. The patient underwent a right lobectomy. The mass was finally diagnosed as a follicular variant of papillary thyroid cancer with massive stromal fat.

The combination of methylsulfonylmethane and tamoxifen inhibits the Jak2/STAT5b pathway and synergistically inhibits tumor growth and metastasis in ER-positive breast cancer xenografts.

BACKGROUND: Combination therapy, which reduces the dosage intensity of the individual drugs while increasing their efficacy, is not a novel approach for the treatment of cancer. Methylsulfonylmethane (MSM) is an organic sulfur compound shown to act against tumor cells. Tamoxifen is a commercially available therapeutic agent for breast malignancies. METHODS: In the current study, we analyzed the combinatorial effect of MSM and tamoxifen on the suppression of ER-positive breast cancer xenograft growth and metastasis. Additionally, we also validated the molecular targets by which the drug combination regulated tumor growth and metastasis. RESULTS: We observed that the combination of MSM and tamoxifen regulated cell viability and migration in vitro. The intragastric administration of MSM and subcutaneous implantation of tamoxifen tablets led to tumor growth suppression and inhibition of the Janus kinase 2 (Jak2)/signal transducer and activator of transcription 5b (STAT5b) pathway. Our study also assessed the regulation of signaling molecules implicated in the growth, progression, differentiation, and migration of cancer cells, such as Jak2, STAT5b, insulin-like growth factor-1Rß, and their phosphorylation status. CONCLUSIONS: Study results indicated that this combination therapy inhibited tumor growth and metastasis. Therefore, this drug combination may have a synergistic and powerful anticancer effect against breast cancer.

Expression of Peroxisome Proliferator Activated Receptor gamma in Prostatic Adenocarcinoma.

Peroxisome proliferator-activated receptor gamma (PPAR-γ), a ligand-activated transcription factor has been investigated as the target for cancer treatment as well as metabolic disorders. Recent studies have demonstrated that PPAR-γ ligands are anti-tumorigenic in prostate cancer due to anti-proliferative and pro-differentiation effects. The aim of this study was to validate PPAR-γ expression in malignant and benign prostate tissues by immunohistochemistry and quantitative real-time polymerase chain reaction (PCR). A total of 730 prostatic adenocarcinomas (PCAs) including 63 whole sections from radical prostatectomy specimens and tissue microarrays containing 667 PCAs were subject to immunostaining for two PPAR-γ antibodies. Twenty-five benign prostate tissues and PCAs were selected for investigating mRNA expression by quantitative real-time PCR. 10.7% of PCAs (78/730) showed cytoplasmic immunoreactivity of PPAR-γ and no nuclear immunoreactivity was noted in PCAs. Most benign prostatic glands showed negative immunoreactivity of PPAR-γ except for variable weak cytoplasmic staining in some glands. Nuclear immunoreactivity of PPAR-γ was noted some central zone and verumontanum mucosal epithelium. The constitutive PPAR-γ mRNA showed significantly lower level in PCAs compared to that in the benign tissues. There was no difference of PPAR-γ mRNA expression between low (≤7) and high (>7) Gleason score groups. There was no association of PPAR-γ mRNA level or cytoplasmic immunostaining with Gleason grade or pathologic stage. Our study supported the evidence of extra-nuclear localization and nongenomic actions of PPAR-γ. Further studies are needed to assess the functional role of PPAR-γ and to validate its therapeutic implication in prostate cancer.

Preoperative RAS mutational analysis is of great value in predicting follicular variant of papillary thyroid carcinoma.

Follicular variant of papillary thyroid carcinoma (FVPTC), particularly the encapsulated subtype, often causes a diagnostic dilemma. We reconfirmed the molecular profiles in a large number of FVPTCs and investigated the efficacy of the preoperative mutational analysis in indeterminate thyroid nodules. BRAF V600E/K601E and RAS mutational analysis was performed on 187 FVPTCs. Of these, 132 (70.6%) had a point mutation in one of the BRAF V600E (n=57), BRAF K601E (n=11), or RAS (n=64) genes. All mutations were mutually exclusive. The most common RAS mutations were at NRAS codon 61. FNA aspirates from 564 indeterminate nodules were prospectively tested for BRAF and RAS mutation and the surgical outcome was correlated with the mutational status. Fifty-seven and 47 cases were positive for BRAF and RAS mutation, respectively. Twenty-seven RAS-positive patients underwent surgery and all except one patient had FVPTC. The PPV and accuracy of RAS mutational analysis for predicting FVPTC were 96% and 84%, respectively. BRAF or RAS mutations were present in more than two-thirds of FVPTCs and these were mutually exclusive. BRAF mutational analysis followed by N, H, and KRAS codon 61 mutational analysis in indeterminate thyroid nodules would streamline the management of patients with malignancies, mostly FVPTC.

RAS mutations in indeterminate thyroid nodules are predictive of the follicular variant of papillary thyroid carcinoma.

OBJECTIVE: RAS mutations are the most common mutations in thyroid nodules with indeterminate cytology by fine-needle aspiration cytology (FNAC), and are mutually exclusive with BRAF mutations. However, the diagnostic utility of RAS mutation analysis is uncertain. We evaluated the diagnostic utility of RAS mutation analysis in indeterminate thyroid nodules. DESIGN, PATIENTS, AND MEASUREMENTS: A total of 155 thyroid nodules (90 benign and 65 indeterminate) negative for BRAF(V) (600E) mutations on FNAC were analysed for mutations in RAS codon 61 using pyrosequencing methods. We evaluated diagnostic accuracy of RAS mutation for predicting thyroid malignancy based on the surgical pathologic diagnosis. RESULTS: Among the 65 BRAF(V) (600E) -negative indeterminate thyroid nodules identified by FNAC, 25 (38·5%) exhibited point mutations in RAS 61 consisting of 18 NRAS 61 (72%), and 7 HRAS 61 (28%) mutations. In contrast, only five of 90 (5·6%) nodules with benign cytology had RAS mutations. Only two of 25 (8·0%) RAS 61(+) indeterminate nodules exhibited malignant ultrasonographic features. Of the 15 patients with RAS 61(+) -indeterminate nodules who underwent thyroid surgery, 14 (93·3%) were diagnosed as malignant, including 13 follicular variant of papillary thyroid carcinomas (FVPTC), and one follicular thyroid carcinoma (FTC). The average tumour size was 1·79 ± 0·62 cm. Multifocality was seen in 28·6% of cases, with 7·1% exhibiting extrathyroidal extension; no lymph node or distant metastases were evident. Based on the surgical pathologic diagnosis results, preoperative RAS 61 mutation analysis on FNAC exhibited 93·3% sensitivity, 75·0% specificity, 93·3% positive predictive value, 75·0% negative predictive value and 89·5% diagnostic accuracy for predicting malignancies. CONCLUSION: Our results suggest that RAS mutation analysis holds great promise as a preoperative diagnostic tool for predicting FVPTC in cytologically and sonographically indeterminate nodules negative for BRAF mutations.

Ileal mass-like lesion induced by Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in a patient with aplastic anemia.

Hemophagocytic lymphohistiocytosis (HLH) is a rare life-threatening hyperinflammatory syndrome characterized by activated macrophages engulfing erythrocytes, leukocytes, platelets, and their precursor cells in bone marrow, liver, spleen, or lymph nodes. We report a case of Epstein-Barr virus (EBV)-associated HLH unusually presenting as an ileal mass. A 23-year-old man presented initially with persistent fever unresponsive to antibiotics and pancytopenia. A bone marrow aspiration and biopsy were used to diagnose the patient with aplastic anemia and HLH. A relatively well-defined low-density mass was radiologically noted in the terminal ileum, along with enlarged lymph nodes, and was suspected to be malignant lymphoma or an abscess. The ileocecectomy specimen revealed a transmural hemorrhagic infarction with numerous activated macrophages phagocytosing erythrocytes, plasma cells, and lymphocytes, and he was diagnosed with EBV-associated HLH. The patient received an allo-unrelated peripheral blood stem-cell transplantation and expired due to graft-versus-host disease following liver failure. The present case is very unique, in that EBV-associated HLH presented with an unusual ileal mass resulting from hemorrhagic infarction in a patient with aplastic anemia, suggesting variability in the biological behavior of EBV-associated disease.

Primary ductal adenocarcinoma of the lacrimal gland, associated with abundant intracytoplasmic lumens containing some eosinophilic hyaline globules: cytological, histological and ultrastructural findings.

A primary ductal adenocarcinoma (PDA) of the lacrimal gland is a rare distinct subtype of an epithelial tumor arising in the lacrimal gland. PDA is the counterpart of salivary duct carcinoma (SDC) resembling an invasive ductal carcinoma (IDC) of the breast. In our case, PDA revealed histopathological and immunohistochemical results corresponding to SDC. Interestingly, the tumor cells showed intracytoplasmic vacuoles containing dense eosinophilic hyaline globules at light microscopy. Ultrastructurally, the tumor cells exhibited microvilli-lined intracytoplasmic lumen containing homogenous electron-dense secretory products. A previous study demonstrated that numerous intracytoplasmic lumens of tumor cells are favored breast malignant tumor, similar to the histopathology of PDA, rather than benign lesion. This characteristic finding may be meaningful to diagnose high grade epithelial tumors including PDA.

ERG Immunohistochemistry as an Endothelial Marker for Assessing Lymphovascular Invasion.

BACKGROUND: ERG, a member of the ETS family of transcription factors, is a highly specific endothelial marker. We investigated whether the use of ERG immunostaining can help pathologists detect lymphovascular invasion (LVI) and decrease interobserver variability in LVI diagnosis. METHODS: Fifteen cases of surgically resected colorectal cancers with hepatic metastasis were selected and the most representative sections for LVI detection were immunostained with ERG, CD31, and D2-40. Eight pathologists independently evaluated LVI status on hematoxylin and eosin (H&E) and the corresponding immunostained sections and then convened for a consensus meeting. The results were analyzed by kappa (κ) statistics. RESULTS: The average rate of LVI positivity was observed in 43% with H&E only, 10% with CD31, 29% with D2-40, and 16% with ERG. Agreement among pathologists was fair for H&E only (κ=0.27), D2-40 (κ=0.21), ERG (κ=0.23), and was moderate for CD31 (κ=0.55). Consensus revealed that ERG nuclear immunoreactivity showed better visual contrast of LVI detection than the other staining, with improved agreement and LVI detection rate (κ=0.65, LVI positivity rate 80%). CONCLUSIONS: The present study demonstrated a superiority with ERG immunostaining and indicated that ERG is a promising panendothelial marker that might help pathologists increase LVI detection and decrease interobserver variability in LVI diagnosis.

Rhabdoid colorectal carcinomas: reports of two cases.

Rhabdoid colorectal carcinomas are very rare and only 10 cases have been previously reported. We report two cases of rhabdoid colorectal carcinoma, one arising in the sigmoid colon of a 62-year-old man and another in the rectum of an 83-year-old woman. In both cases, the patients had advanced tumors with lymph node metastases. The tumors mostly showed a diffuse arrangement with rhabdoid features and small glandular regions were combined. Transitional areas from the adenocarcinomas to the rhabdoid tumors were also noted. Adenocarcinoma cells were positive for mixed cytokeratin (CK), CK20 and epithelial membranous antigen (EMA), but focal positive for vimentin. The rhabdoid tumor cells were positive for mixed CK, but focal positive or negative for CK20 and EMA. In addition, they were diffusely positive for vimentin, but negative for desmin. The histological and immunohistologial findings of these two cases suggest that the rhabodid tumor cells originated from dedifferentiated adenocarcinomas.