Low‐grade serous carcinoma detected from intraoperative peritoneal washings: Cytological findings and detection of KRAS mutation

Background

Low‐grade serous carcinoma (LGSC) of the ovary, which is extremely rare tumor, has better prognosis than high‐grade serous carcinoma (HGSC). Genetic backgrounds of those are different, so that LGSC usually shows KRAS or BRAF mutation, whereas HGSC does not show such mutations. Since treatment strategies of those are different, differential pathological diagnosis between LGSC and HGSC is very important.

Case

We report a case of LGSC that was diagnosed by both cytological findings and genetic analysis using small amount cells from cytological specimen. The 30‐year‐old Japanese woman with bilateral ovarian tumors underwent salpingo‐oopherectomy. The peritoneal washing cytologic specimen and touched cytologic specimen from the tumor included non‐complex clusters with psammoma bodies composed of tumor cells with mild to moderate atypia and without bizarre nuclei. The ovarian tumor was histologically diagnosed as LGSC. The genetic analysis that was done using exfoliated cells from peritoneal washings specimen by idensy™, detected KRAS mutation at codon 12/13.

Conclusion

The genetic investigation using cytological specimen as well as characteristic cytological findings were useful to make differential diagnosis between LGSC and HGSC.

Adrenocortical carcinoma with inferior vena cava tumor thrombus found during surgery

Introduction

The safety and efficacy of minimally invasive approaches for adrenocortical carcinoma with inferior vena cava tumor thrombus have not yet been established. We report a case of large adrenocortical carcinoma with inferior vena cava tumor thrombus found perioperatively which required conversion from a laparoscopic to an open procedure.

Case presentation

A 71‐year‐old woman with right‐side 10‐cm diameter adrenocortical carcinoma was scheduled for laparoscopic adrenalectomy. The operation was converted to open surgery, however, because inferior vena cava tumor thrombus, which was not detected by preoperative imaging modalities, was found during surgery.

Conclusion

In patients with large adrenocortical carcinoma, the possible presence of inferior vena cava thrombus should be considered when selecting surgical procedures.

Intracranial Hemorrhage in a Patient with TAFRO Syndrome Treated with Cyclosporine A and Rituximab

TAFRO syndrome, a rare subtype of idiopathic multicentric Castleman disease, manifests as thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly. Thrombotic microangiopathy, including renal dysfunction, is frequently associated with this syndrome. TAFRO syndrome can be life threatening and show rapid progression, and the diagnosis and management of this disorder remain challenging. A 48-year-old woman was diagnosed with TAFRO syndrome complicated by thrombotic microangiopathy based on the clinical and histopathological findings. After receiving high-dose steroids, her thrombocytopenia and anasarca did not improve. The patient subsequently received a combination of cyclosporine A and rituximab as second-line therapy, which resulted in a significant gradual improvement in the clinical symptoms. Meanwhile, her platelet count increased to more than 40 × 10⁹/L; however, she developed intracranial hemorrhage. Following surgical evacuation, the patient recovered with an achievement of sustained remission. Based on these findings, attention should be paid to life-threatening bleeding associated with local thrombotic microangiopathy even when intensive treatment is administered for TAFRO syndrome.

[Erdheim-Chester disease diagnosed with right atrium tumors]

Erdheim-Chester disease (ECD) is a very rare form of the non-Langerhans histiocytic multisystem disorder. The cardiac involvement is often challenging and is associated with poor prognosis. Transthoracic echocardiography was used to detect right atrium tumors in a 62-year-old man with heart failure who was admitted to our hospital. The circumferential soft tissue sheathing of the aorta (coated aorta) and fat infiltration around the kidneys (hairy kidneys) was seen on a contrast-enhanced computed tomography strongly suspecting ECD imaging. The patient was diagnosed with ECD based on histopathology reports of the surgical resection tumor. The characteristic imaging findings of ECD may contribute to an early and accurate diagnosis.

Paneth-like cells in renal cell carcinomas and in cysts associated with acquired cystic kidney disease: Clinicopathologic analysis, comparative study and description of precursor lesions

Paneth-like cells (PLCs) are different from Paneth cells (PCs) and contain Paneth-like granules, which have been reported in non-neoplastic conditions and in neoplasms of various organs. PLCs have been reported in clear cell renal cell carcinoma (CCRCC), but not in non-CCRCC, including acquired cystic disease-associated renal cell carcinoma (ACD-RCC). We analyzed clinicopathological features of 24 acquired cystic disease-associated renal cell carcinoma (ACD-RCC) with PLCs (ACD-RCCP+) and compared with those of 23 ACD-RCCs without PLCs (ACD-RCCP-). Approximately half of ACD-RCCs had PLCs and that almost all kidneys harboring ACD-RCC had cysts with PLCs. The fact that many ACD-RCCs and the cysts had PLCs is further evidence that the cyst with vacuoles and complex architecture might be a precursor lesion for ACD-RCC. The presence of PLCs may provide additional morphologic clue for distinguishing ACD-RCC from PRCC in challenging differential diagnostic workup in acquired cystic disease of the kidney setting.

False-positive staining of thyroglobulin distinguished from mixed medullary and follicular thyroid carcinoma by duplex in situ hybridization

Medullary thyroid carcinoma (MTC) may mimic mixed medullary and follicular thyroid carcinoma (MMFTC). MTC originates from para-follicular cells, while MMFTC is an uncommon tumor characterized by coexistence of follicular and para-follicular cell-derived tumor populations. A 35-year-old woman was diagnosed with MTC but showed a hot nodule in thyroid scintigraphy. The tumor included diffusely-spread follicular lesions within it, which were immunostained with thyroglobulin and calcitonin. Immunofluorescence showed the presence of several tumor cells that were double-stained with thyroglobulin and calcitonin. To clarify whether or not the tumor was MMFTC, we used duplex in situ hybridization (ISH). Thyroglobulin and calcitonin-related polypeptide alpha mRNA were not expressed together in a single cell, so we suspected false-positive staining of tumor cells with thyroglobulin. To make comparisons with other follicular lesions in MTC, we searched our hospital database. Five cases within a ten-year period had been pathologically diagnosed as MTC. All had follicular lesions in the tumor, but unlike the other case, they were peripherally localized. Dual differentiation into follicular or para-follicular tumor cells was not indicated by either immunofluorescence or duplex ISH. Compared with the case suspected to be MMFTC, there was only mild invasion of tumor cells into the follicular epithelium. The extent of follicular lesions and invasiveness of tumor cells may be associated with pseudo-staining of thyroglobulin in MTC. Duplex ISH can distinguish MTC that are stained with thyroglobulin from MMFTC.

Microtubule-organizing center-mediated structural atypia in low- and high-grade urothelial carcinoma

Urothelial carcinoma (UC) comprises two subtypes, low grade (LG-UC) and high grade (HG-UC), with different pathological and clinical behavior. LG-UC and HG-UC are classified based on cellular and structural atypia of pathological findings. The mechanisms responsible for maintaining structural atypia, such as the disturbance of nuclear polarity, remain unclear. In this study, we studied microtubule-organizing center (MTOC)-mediated nuclear polarity in UC subtypes. We evaluated six cases with normal urothelium (NU), 10 LG-UC cases, and 10 HG-UC cases by double immunofluorescence staining of γ-tubulin as a marker of MTOC and E-cadherin as a marker of each cell border. The number and position of γ-tubulin dots of expression in more than 100 cells per case were assessed using the spatial relationship with the nucleus and surface-basal axis. We found one γ-tubulin dot in most normal and tumor cells, and more than two γ-tubulin dots in 4.6% of NU cells, 6.1% of LG-UC cells, and 9.8% of HG-UC cells. More than three γ-tubulin dots were found only in 1.2% of HG-UC cells. Surface side positioning of γ-tubulin was found in 77.4% of normal urothelial cells, 63.8% of LG-UC cells, and 39.2% of HG-UC cells, whereas aberrant lateral and basal side positioning of γ-tubulin was found in 22.6% of normal urothelial cells, 36.1% of LG-UC cells, and 60.8% of HG-UC cells. We concluded that numerical and positional aberrations of MTOC in UC cases were strongly correlated with both cellular and structural atypia as well as abnormal cell proliferation.

Measurement and visualization of cell membrane surface charge in fixed cultured cells related with cell morphology

The diagnosis of patients with malignancies relies on the results of a clinical cytological examination. To enhance the diagnostic qualities of cytological examinations, it is important to have a detailed analysis of the cell’s characteristics. There is, therefore, a need for developing a new auxiliary method for cytological diagnosis. In this study, we focused on studying the charge of the cell membrane surface of fixed cells, which is one of important cell’s characteristics. Although fixed cells lose membrane potential which is observed in living cells owing to ion dynamics, we hypothesized that fixed cells still have a cell membrane surface charge due to cell membrane components and structure. We used 5 cell lines in this study (ARO, C32TG, RT4, TK, UM-UC-14). After fixation with CytoRich Red, we measured the cell membrane surface charge of fixed cells in solution using zeta potential measurements and fixed cells on glass slides, visualizing it using antibody-labeled beads and positively-charged beads. Furthermore, we measured the cell membrane surface charge of fixed cells under different conditions, such as different solution of fixative, ion concentration, pH, and pepsin treatments. The zeta potential measurements and visualization using the beads indicated that the cell membrane surface of fixed cells was negatively charged, and also that the charge varied among fixed cells. The charge state was affected by the different treatments. Moreover, the number of cell-bound beads was small in interphase, anaphase, and apoptotic cells. We concluded that the negative cell membrane surface charge was influenced by the three-dimensional structure of proteins as well as the different types of amino acids and lipids on the cell membrane. Thus, cell surface charge visualization can be applied as a new auxiliary method for clinical cytological diagnosis. This is the first systematic report of the cell membrane surface charge of fixed cells.

Balloon-Assisted Embolization of Wide-Neck Aneurysms Using a Mixture of n-Butyl Cyanoacrylate, Lipiodol, and Ethanol in Swine: A Comparison of Four n-Butyl Cyanoacrylate Concentrations

PURPOSE

To determine the optimal ratio of n-butyl cyanoacrylate (NBCA)-Lipiodol-ethanol (NLE) mixture for balloon-assisted embolization of wide-neck aneurysms.

MATERIALS AND METHODS

We created 32 wide-neck aneurysms on both the common carotid arteries and external iliac arteries in eight female swine. Eight aneurysms were randomly assigned to four groups. Under balloon occlusion, the aneurysms were packed using NLE at one of four ratios of NLE: 2:2:1 (NLE221; 40%NBCA); 3:6:1 (NLE361; 30%NBCA); 2:7:1 (NLE271; 20%NBCA); and 1:5:1 (NLE151; 14.3%NBCA). We performed angiography before and after embolization to assess the aneurysms, and we compared adhesion between NLE and the balloon and assessed NLE migration. Three days after embolization, the aneurysms were removed for histopathologic evaluation.

RESULTS

Embolization was performed in 27 aneurysms. Adhesion between NLE and the balloon was not observed in any group. NLE migration was found in 0/7 aneurysms in the NLE221 group, 0/6 in the NLE361 group, 5/6 in the NLE271 group, and 7/8 in the NLE151 group. NLE migration was significantly lower in the NLE221 group than in the NLE271 and NLE151 groups (P = 0.0047 and 0.0014, respectively) and was significantly lower in the NLE361 group than in the NLE271 and NLE151 groups (P = 0.0152 and 0.0047, respectively). Media necrosis of the arterial wall close to the aneurysms was observed in all groups.

CONCLUSION

NLE with an NBCA concentration of ≥ 30% is a safe and feasible embolic material for balloon-assisted embolization of wide-neck aneurysms in swine in the short term up to 3 days after embolization.

Brentuximab vedotin for refractory anaplastic lymphoma kinase-negative anaplastic large cell lymphoma in leukemic phase with RUNX3 overexpression

Anaplastic lymphoma kinase (ALK)- negative anaplastic large cell lymphoma (ALCL) is an aggressive CD30-positive non- Hodgkin lymphoma. ALK-ALCL rarely manifests with extensive bone marrow and peripheral blood involvement (known as “leukemic phase”). A 54-year-old woman was diagnosed with ALK-ALCL in leukemic phase, characterized by an extremely poor prognosis. Lymphoma cells in this case showed chromosomal translocation 1p36.1- encoded RUNX3 and overexpression of its protein. She was refractory to CHOP and salvage chemotherapy. Fortunately, she achieved complete remission with three cycles of Brentuximab vedotin (BV) and underwent umbilical cord blood transplantation. However, she died due to treatment-related mortality on day 129. The autopsy findings showed no lymphoma cells. Treatment strategy for ALK-ALCL is controversial, but the efficacy of BV in CD30-positive peripheral T-cell lymphoma not only as salvage regimens, but also in first line, has been reported in recent years. BV may be an effective option for ALK-ALCL in leukemic phase.

Head and Neck Paraganglioma Atypically Carrying a Succinate Dehydrogenase Subunit B Mutation (L157X)

A 53-year-old woman was admitted to a hospital for gradual left-ear hearing loss over 2 years. Head computed tomography revealed a 2-cm mass along the left jugular bulb and another at the right carotid bulb. The right tumor was resected; the pathological diagnosis was carotid body paraganglioma. Mutations of succinate dehydrogenase (SDH) were suspected, but SDHB staining remained in the tumor. Genetic testing identified a known SDHB mutation (L157X). The patient had head and neck paraganglioma with an SDHB mutation (L157X) more typical of an SDHD mutation. SDHB immunohistochemistry is useful for detecting SDHx mutations, but careful interpretation is needed.

Adipophilin expression in cutaneous malignant melanoma is associated with high proliferation and poor clinical prognosis

Adipophilin (ADP) is a primary protein component of lipid droplets (LDs). For more than half a century, certain types of cancer cells have been known to contain LDs in their cytoplasm. However, the pathological significance of ADP or LDs in cancer remains unclear. In the present study, we investigated the association between ADP and other pathological characteristics in cutaneous malignant melanomas to clarify the role of ADP in melanoma cells. We immunostained whole paraffin sections of primary cutaneous melanomas obtained from 90 cases for ADP, after which we analyzed the correlation between ADP immunohistochemistry (IHC) and patient survival data. We also studied the relationship between the ADP IHC score and in situ hybridization (ISH) score of ADP mRNA, and the Ki67-labeling index (Ki67-LI) by using tissue microarrays consisting of 74 primary cutaneous malignant melanomas, 19 metastasizing melanomas, and 29 melanocytic nevi. Finally, we analyzed the relationship between ADP expression and cell proliferation in cutaneous melanoma cell lines. We found that high ADP expression was associated with poor metastasis-free survival, disease-specific survival, and overall survival rates of patients with cutaneous melanomas (P < 0.05). By linear regression analysis, ADP IHC was correlated with increasing ADP mRNA ISH H-scores and Ki67-LI scores in melanocytic lesions (P < 0.01). ADP IHC and ADP ISH H-scores and Ki67-LI scores were greater in pT3-4 melanomas than in pT1-2 melanomas. In cell-based assays, cells with increased ADP expression showed higher proliferation rates compared with those of low-ADP cells. Thus, ADP expression in malignant melanoma was significantly associated with high cell proliferation and poor clinical prognosis. Our results thus indicate a significant association between ADP and melanoma progression, and we propose that ADP may be a novel marker of aggressive cutaneous melanoma with a lipogenic phenotype.

A rare case of the recurrent surgery for cribriform-morular variant of papillary thyroid carcinoma

INTRODUCTION

The cribriform-morular variant of papillary thyroid carcinoma (CMV-PTC) is an uncommon subtype of PTC, and it is associated with familial adenomatous polyposis (FAP).

PRESENTATION OF CASE

We describe a 32-year-old female who presented recurrent CMV-PTC with FAP. Surgery performed after the recurrent disease resulted in left recurrent laryngeal nerve palsy due to formation of strong scar after initial operation. The histopathological examination revealed the recurrent CMV-PTC without thyroid capsular invasion in remnant thyroid tissue of berry ligament. In addition, the immunohistochemical analysis showed that β-Catenin was diffusely positive in both cytoplasm and nucleus in CMV-PTC tissue.

CONCLUSION

Total thyroidectomy in CMV-PTC with FAP should be performed at initial surgery due to high recurrence.

Predominant Improvement of Alpha Cell Function after Steroid Therapy in a Patient with Autoimmune Pancreatitis: Case Report

INTRODUCTION

Autoimmune pancreatitis (AIP) is a subset of inflammatory pancreatic disease, responsive to corticosteroid therapy. It is prone to being affected by diabetes mellitus, but the effectiveness of steroid therapy on pancreatic endocrine function is still controversial. We present a case of AIP, focusing on pancreatic endocrine function after steroid therapy.

CASE REPORT

The patient was referred to our hospital with exacerbation of diabetic control and pancreatic swelling. By admission, the insulin secretory capacity was severely impaired. The patient was diagnosed with AIP and treated with prednisolone, resulting in marked improvement of the pancreatic swelling. Glycemic control worsened transiently after initiation of steroid therapy, but insulin requirements decreased along with tapering prednisolone dosage. Pancreatic cytology showed that the acinar structure had been destroyed, and the islets had disappeared. Insulin and glucagon immunostaining revealed slightly scattered alpha and beta cells within the fibrotic stroma. The patient notably showed improved pancreatic alpha cell function predominantly after steroid therapy, despite partial improvement of beta cell function.

CONCLUSION

An imbalance between alpha and beta cell function may contribute to insufficient diabetic control in some patients with AIP. The pancreatic endocrine function test in combination with pancreatic cytology could be helpful when considering the treatment strategy for diabetic control in patients with AIP.

HER2 is frequently overexpressed in hepatoid adenocarcinoma and gastric carcinoma with enteroblastic differentiation: a comparison of 35 cases to 334 gastric carcinomas of other histological types

AIMS

α-Fetoprotein (AFP)-producing gastric carcinoma (AFPGC) is one of the most aggressive GC subtypes. Frequent expression of human epidermal growth factor receptor 2 (HER2) has previously been reported in hepatoid adenocarcinoma (HAC), a major histological subtype of AFPGC originating from common-type GC (CGC). However, HER2 expression levels in other AFPGC histological subtypes are unknown. In this study, we analysed HER2 expression in GCs with primitive phenotypes in addition to HAC.

METHODS

HER2 expression was evaluated in representative complete sections from 16 HACs, 19 GCs with enteroblastic differentiation (GCEDs) and 334 GCs of other histological types as controls. The Ruschoff/Hofmann method was used to score HER2 immunohistochemistry. Samples with a HER2 score of 2+ were further assessed using fluorescence in situ hybridisation. Oncofetal protein (OFP) expression in HAC and GCED was tested via immunohistochemical staining for AFP, glypican 3 and Sal-like protein 4.

RESULTS

Thirty of 35 HAC/GCED cases comprised more than two histological patterns. The HER2 positivity rates of each histological component in the HACs/GCEDs were 25.0% for HAC (n=16), 34.6% for GCED (n=26) and 48.1% for CGC (n=27), which were higher than those of the control group (13.8%). Additionally, the majority of CGC components in HACs/GCEDs were positive for OFP (88.9%).

CONCLUSIONS

HER2 is frequently overexpressed not only in HAC but also in GCED and CGC components of HACs/GCEDs, which suggests an association between HER2 and OFP expression. Moreover, our findings suggest that HER2-positive CGC has a higher risk of progression to HAC/GCED than HER2-negative GC.

Novel Application of Loop-mediated Isothermal Amplification for Rapid Detection of Gene Translocation

Identification of fusion genes in cancer is essential for pathological diagnosis and clinical therapy. Although methods for detection of fusion genes, such as fluorescence in situ hybridization (FISH) and real-time polymerase chain reaction (PCR), have been developed in last two decades, these methods are not ideal for detection of these genetic alterations owing to their high cost and time-consuming procedures. In this study, we developed novel application for detection of gene translocations using loop-mediated isothermal amplification (LAMP). We verified the amplified DNA products of echinoderm microtubule-associated protein-like 4 and anaplastic lymphoma kinase (EML4-ALK), synaptotagmin and synovial sarcoma, X breakpoint (SYT-SSX), and immunoglobulin heavy chain gene and B cell leukemia/lymphoma 2 (IgH/BCL2) by real-time PCR, agarose-gel electrophoresis, and the naked eye after the LAMP procedure. Fusion genes were detected in samples diluted 103 times within 60 min. Because of the advantages of rapid amplification, simple operation, and easy detection without requiring sophisticated equipment or technical skill, LAMP may have potential applications as an on-site analytical approach in hospitals for pathological diagnosis and decision making regarding appropriate therapeutic approachs.

Endoscopic ultrasound-guided biliary drainage using a newly designed metal stent with a thin delivery system: a preclinical study in phantom and porcine models

PURPOSE

This study was designed to evaluate the feasibility and safety of a newly designed self-expandable metal stent for endoscopic ultrasound-guided biliary drainage (EUS-BD) when it was delivered via three different stent delivery systems: a 7.5Fr delivery catheter with a bullet-shaped tip (7.5Fr-bullet), a 7Fr catheter with a bullet-shaped tip (7Fr-bullet), or a 7Fr catheter with a tee-shaped tip (7Fr-tee).

METHODS

This experimental study utilized a porcine model of biliary dilatation involving ten pigs. In the animal study, technical feasibility and clinical outcomes of the stent when placed with each of the delivery systems were examined. In addition, a phantom model was used to measure the resistance of these delivery systems to advancement.

RESULTS

Phantom experiments showed that, compared with 7Fr-bullet, 7Fr-tee had less resistance force to the advancement of the stent delivery system. EUS-BD was technically successful in all ten pigs. Fistulous tract dilation was necessary in 100% (2/2), 75% (3/4), and 0% (0/4) of the pigs that underwent EUS-BD using 7.5Fr-bullet, 7Fr-bullet, and 7Fr-tee, respectively. There were no procedure-related complications.

CONCLUSION

Our newly designed metal stent may be feasible and safe for EUS-BD, particularly when delivered by 7Fr-tee, because it eliminates the need for fistulous tract dilation.

Effective localization in tumor-induced osteomalacia using 68Ga-DOTATOC-PET/CT, venous sampling and 3T-MRI

Summary

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome characterized by renal phosphate wasting leading to hypophosphatemia due to excessive actions of fibroblast growth factor 23 (FGF23) produced by the tumors. Although the best way of curing TIO is complete resection, it is usually difficult to detect the culprit tumors by general radiological modalities owing to the size and location of the tumors. We report a case of TIO in which the identification of the tumor by conventional imaging studies was difficult. Nonetheless, a diagnosis was made possible by effective use of multiple modalities. We initially suspected that the tumor existed in the right dorsal aspect of the scapula by ⁶⁸Ga-DOTATOC positron emission tomography/computed tomography (⁶⁸Ga-DOTATOC-PET/CT) and supported the result by systemic venous sampling (SVS). The tumor could also be visualized by 3T-magnetic resonance imaging (MRI), although it was not detected by 1.5T-MRI, and eventually be resected completely. In cases of TIO, a stepwise approach of ⁶⁸Ga-DOTATOC-PET/CT, SVS and 3T-MRI can be effective for confirmation of diagnosis.

Learning points:

Adipophilin expression in cutaneous malignant melanoma

BACKGROUND

The lipogenic pathway is upregulated in cancer cells, including melanomas. However, the pathological significance of cellular lipids in melanocytic lesions has yet to be determined. In this study, we evaluated intracytoplasmic lipid droplets in melanocytic nevi (MNs) and malignant melanomas via immunohistochemical analysis of adipophilin (ADP), which coats lipid droplets.

METHODS

One hundred primary cutaneous melanocytic lesions [33 MNs, 17 melanomas in situ (MIS), and 50 invasive melanomas (IMs)] were immunostained for ADP. The intensity score (IS) and proportion score (PS) of ADP staining in each case was recorded semiquantitatively on a scale of 0 to 3+.

RESULTS

High ADP expression (IS2/3+ and PS2/3+) was observed in 27 primary cutaneous melanocytic lesions that consisted of 23 IMs, three MISs, and one MN. Consequently, high ADP expression was associated with malignancy (38.8% vs. 3.0%; p < 0.0001). Among the IMs, high ADP expression was more prevalent in pT3/4 than pT1/2 (63.3% vs. 23.8%; p = 0.01) and Stage 3/4 than Stage 1/2 (76.9% vs. 36.8%; p = 0.02).

CONCLUSIONS

The majority of the melanocytic lesions with high ADP expression were malignant melanomas in our cohort. Therefore, ADP expression may serve as a sensitive diagnostic marker for malignant melanoma.

Refractory Ascites with Liver Fibrosis Developed in Late Phase Allogeneic Hematopoietic Stem Cell Transplantation: Report of Three Patients

We report cases of three patients of refractory ascites without other fluid retention that occurred around five months after allogeneic hematopoietic stem cell transplantation (allo-HSCT). All three patients expired and postmortem examinations revealed unexpected liver fibrosis lacking histological evidences of graft-versus-host-disease (GVHD). The three patients showed normal hepatic function and size before transplantation. During their clinical courses, serum biochemistry test showed no elevation of hepatic enzymes and bilirubin; however, imaging studies demonstrated hepatic atrophy at the onset of ascites. One of the liver specimens showed bile obstruction, which could be seen in hepatic damage by GVHD. Although ascites resulting from venoocclusive disease in early phase allo-HSCT is well documented, ascites associated with hepatic fibrosis in late phase allo-HCST has not been reported. Further clinico-pathological studies on similar patients should be required to ascertain refractory ascites associated with liver fibrosis after allo-HSCT.

Synthesis of 24-h soluble gelatin sponge particles and their effect on liver necrosis following hepatic artery embolization: Results of in vitro and in vivo studies

AIM

To synthesize 24-h soluble gelatin sponge particles (SGSP) of 200-500 and 500-1000 µm, and to investigate their ischemic potency following hepatic artery embolization (HAE).

METHODS

Low-endotoxin gelatin was freeze-dried and heated at 110, 115, 118, 120, 122 and 125°C to form cross-linked gelatin sponge. We prepared 200-500- and 500-1000-µm SGSP by pulverizing and sieving the gelatin sponge. The dissolution times in saline were measured. Eight healthy pigs underwent HAE of the right and left hepatic arteries with either 200-500- or 500-1000-µm SGSP (n = 4/group).

RESULTS

The particles prepared at 110-122°C were soluble whereas particles prepared at 125°C or more were insoluble. The mean dissolution time of the particles increased with increasing temperature. In each pig, sequential arteriography confirmed that recanalization was complete 24 h after embolization. Pathological tests 48 h after HAE revealed coagulation necrosis but least damage to the biliary tract. The liver necrosis rate (mean ± standard deviation) was significantly greater in the 200-500-µm group than in the 500-1000-µm group (9.89 ± 4.04% vs 4.44 ± 0.67%, respectively; P = 0.0027). A significantly greater proportion of arteries with a diameter of 100-200 µm had residual SGSP in the 200-500-µm group than in the 500-1000-µm group (P < 0.002).

CONCLUSION

HAE with 200-500-µm SGSP had greater effects on promoting liver necrosis without biliary damage than did HAE with 500-1000-µm SGSP.

Novel Methodology for Rapid Detection of KRAS Mutation Using PNA-LNA Mediated Loop-Mediated Isothermal Amplification

Detecting point mutation of human cancer cells quickly and accurately is gaining in importance for pathological diagnosis and choice of therapeutic approach. In the present study, we present novel methodology, peptide nucleic acid—locked nucleic acid mediated loop-mediated isothermal amplification (PNA-LNA mediated LAMP), for rapid detection of KRAS mutation using advantages of both artificial DNA and LAMP. PNA-LNA mediated LAMP reactions occurred under isothermal temperature conditions of with 4 primary primers set for the target regions on the KRAS gene, clamping PNA probe that was complimentary to the wild type sequence and LNA primers complementary to the mutated sequences. PNA-LNA mediated LAMP was applied for cDNA from 4 kinds of pancreatic carcinoma cell lines with or without KRAS point mutation. The amplified DNA products were verified by naked-eye as well as a real-time PCR equipment. By PNA-LNA mediated LAMP, amplification of wild type KRAS DNA was blocked by clamping PNA probe, whereas, mutant type KRAS DNA was significantly amplified within 50 min. Mutant alleles could be detected in samples which diluted until 0.1% of mutant-to-wild type ratio. On the other hand, mutant alleles could be reproducibly with a mutant-to-wild type ratio of 30% by direct sequencing and of 1% by PNA-clamping PCR. The limit of detection (LOD) of PNA-LNA mediated LAMP was much lower than the other conventional methods. Competition of LNA clamping primers complementary to two different subtypes (G12D and G12V) of mutant KRAS gene indicated different amplification time depend on subtypes of mutant cDNA. PNA-LNA mediated LAMP is a simple, rapid, specific and sensitive methodology for the detection of KRAS mutation.

Correlation analysis of nuclear morphology, cytokeratin and Ki-67 expression of urothelial carcinoma cells

We aimed to delineate the morphogenesis of aberrant nuclear features of urothelial carcinoma (UC) cells in association with cytokeratin (CK) expression patterns and cell proliferation activity. Correlation analysis of the nuclear area by morphometry and the expression patterns of CK5, CK20 and Ki-67 by triple immunofluorescence analysis was applied to 1699 cells from five low-grade and seven high-grade cases of UC. The majority of UC cells showed aberrant cellular differentiation represented by abnormal CK expression patterns of CK5+ / CK20+ (40.5%) or CK5- / CK20+ (56.0%). CK5+ / CK20- cells, a phenotype of cancer stem/progenitor cells, represented a very small population (1.9%) and showed a low proliferation activity. Ki-67+ cells showed a significantly different CK expression pattern compared with that of Ki-67(-) cells. The nuclear areas of CK5- / CK20+ cells (71.3 ± 25.9 μm2) were significantly larger than those of CK5+ / CK20+ cells (66.6 ± 25.5 μm2). Negativity for CK5 was related to the grade of UC and an increased number of CK5- / CK20+ / Ki-67+ cells was related to a higher malignant potential. We conclude the nuclear morphology is related to cell differentiation represented by CK expression and cell proliferative activity.

Microtubule-organizing center-mediated nuclear polarity in various normal and neoplastic human tissues

Nuclear polarity is characterized by intracytoplasmic nuclear positioning and alignment in the tissue. The mechanisms responsible for maintaining nuclear polarity in normal cells and its disturbance in neoplastic cells are not understood. We studied microtubule-organizing center (MTOC) positioning-mediated nuclear polarity in various normal and neoplastic human tissues, as well as in cultured cells. To visualize the MTOC in cells, gamma-tubulin and pericentrin were immunohistochemically stained by fluorescence and non-fluorescence methods. Position of MTOC in normal and neoplastic tissue was assessed by spatial relationship with nucleus and apico-basal axis. We found MTOC positioning to be related to morphogenesis in various normal and neoplastic human tissues, as well as in cultured cells. MTOC positions were different between two-dimensional cultured isolated cells and three-dimensional cultured gland-formed cells. The MTOC position was specific depending on the cell type in the tissue structure. In particular, glandular and urothelial epithelium had a strong relationship with preservation of nuclear polarity and MTOC positioning. Carcinoma cells showed an irregular position or absence of the MTOC depending on poorer differentiation and higher grade of carcinomas. In conclusion, the position of the MTOC affects regulation of nuclear polarity and morphogenesis of normal and pathological tissue structure.

Significant Correlation between Chromosomal Aberration and Nuclear Morphology in Urothelial Carcinoma

We aimed to identify whether there is any correlation between chromosomal/genetic changes, nuclear morphology and the histological grade of urothelial carcinomas of the urinary bladder. Morphometry and multicolour fluorescence in situ hybridisation (FISH) techniques were applied to 250 cells in five low-grade cases and 350 cells in seven high-grade cases of urothelial carcinoma. Compared with low-grade carcinomas, most high-grade cases showed larger and more variable nuclear size, more frequent polysomy of centromere enumeration probes (CEPs) 3, 7 and 17, and the loss of the 9p21 locus. The number of CEP signals in cells was increased as the nuclear area of the cells became larger. Cells with gains in two or more types of CEP had significantly larger nuclei than cells with normal FISH signal patterns. In conclusion, the present study indicates that there was a correlation between nuclear morphology and chromosomal/genetic changes which were related to histological grading. Thus, we show that differences in the chromosomal/genetic aberrations present in low- and high-grade tumours can affect not only nuclear morphology but also the histopathological and clinical behaviour of urothelial carcinomas.