Therapeutic potential of pentamidine for glioma-initiating cells and glioma cells through multimodal antitumor effects

Glioma-initiating cells, which comprise a heterogeneous population of glioblastomas, contribute to resistance against aggressive chemoradiotherapy. Using drug reposition, we investigated a therapeutic drug for glioma-initiating cells. Drug screening was undertaken to select candidate agents that inhibit proliferation of two different glioma-initiating cells lines. The alteration of proliferation and stemness of the two glioma-initiating cell lines, and proliferation, migration, cell cycle, and survival of these two differentiated glioma-initiating cell lines and three different glioblastoma cell lines treated with the candidate agent were evaluated. We also used a xenograft glioma mouse model to evaluate anticancer effects of treated glioma cell lines. Among the 1301 agents, pentamidine-an antibiotic for Pneumocystis jirovecii-emerged as a successful antiglioma agent. Pentamidine treatment suppressed proliferation and stemness in glioma-initiating cell lines. Proliferation and migration were inhibited in all differentiated glioma-initiating cells and glioblastoma cell lines, with cell cycle arrest and caspase-dependent apoptosis induction. The in vivo study reproduced the same findings as the in vitro studies. Pentamidine showed a stronger antiproliferative effect on glioma-initiating cells than on differentiated cells. Western blot analysis revealed pentamidine inhibited phosphorylation of signal transducer and activator of transcription 3 in all cell lines, whereas Akt expression was suppressed in glioma-initiating cells but not in differentiated lines. In the present study, we identified pentamidine as a potential therapeutic drug for glioma. Pentamidine could be promising for the treatment of glioblastomas by targeting both glioma-initiating cells and differentiated cells through its multifaceted antiglioma effects.

COL1A2 inhibition suppresses glioblastoma cell proliferation and invasion

OBJECTIVE

An extracellular matrix such as collagen is an essential component of the tumor microenvironment. Collagen alpha-2(I) chain (COL1A2) is a chain of type I collagen whose triple helix comprises two alpha-1 chains and one alpha-2 chain. The authors' proteomics data showed that COL1A2 is significantly higher in the blood of patients with glioblastoma (GBM) compared with healthy controls. COL1A2 has many different functions in various types of cancers. However, the functions of COL1A2 in GBM are poorly understood. In this study, the authors analyzed the functions of COL1A2 and its signaling pathways in GBM.

METHODS

Surgical specimens and GBM cell lines (T98, U87, and U251) were used. The expression level of COL1A2 was examined using GBM tissues and normal brain tissues by quantitative real-time polymerase chain reaction. The clinical significance of these levels was evaluated using Kaplan-Meier analysis. Small interfering RNA (siRNA) and small hairpin RNA of COL1A2 were transfected into GBM cell lines to investigate the function of COL1A2 in vitro and in vivo. Flow cytometry was introduced to analyze the alteration of cell cycles. Western blot and immunohistochemistry were performed to analyze the underlying mechanisms.

RESULTS

The expression level of COL1A2 was upregulated in GBM compared with normal brain tissues. A higher expression of COL1A2 was correlated with poor progression-free survival and overall survival. COL1A2 inhibition significantly suppressed cell proliferation in vitro and in vivo, likely due to G1 arrest. The invasion ability was notably deteriorated by inhibiting COL1A2. Cyclin D1, cyclin-dependent kinase 1, and cyclin-dependent kinase 4, which are involved in the cell cycle, were all downregulated after blockade of COL1A2 in vitro and in vivo. Phosphoinositide 3-kinase inhibitor reduced the expression of COL1A2. Although downregulation of COL1A2 decreased the protein kinase B (Akt) phosphorylation, Akt activator can phosphorylate Akt in siRNA-treated cells. This finding suggests that Akt phosphorylation is partially dependent on COL1A2.

CONCLUSIONS

COL1A2 plays an important role in driving GBM progression. COL1A2 inhibition attenuated GBM proliferation by promoting cell cycle arrest, indicating that COL1A2 could be a promising therapeutic target for GBM treatment.

Swallowing-induced Paroxysmal Atrial Tachycardia Causes Weight Loss and Fainting during Mealtime: A Case Report and Literature Review

Swallow or deglutition syncope is an unusual disorder. We herein report an 80-year-old man with paroxysmal atrial tachycardia induced by swallowing, causing syncope. Initially, we suspected a digestive disorder and found no significant findings. Finally, a swallowing test with monitoring of the heart rate and blood pressure helped in the diagnosis. The patient was treated with antiarrhythmic drugs and catheter ablation. The mechanism underlying swallowing-induced tachycardia presumably involves mechanical stimulation of the esophagus and autonomic nervous system effects. However, few cases have been reported, and the exact mechanism remains unclear.

STEM-17. IDENTIFICATION OF LOMERIZINE, A PROPHYLACTIC DRUG FOR MIGRAINES, AS A POTENTIAL ANTI-GLIOBLASTOMA DRUG

BACKGROUND

Glioblastoma (GBM) is one of the most malignant primary brain tumors. Despite development of treatment, prognosis of GBM is still poor. Here, we identified lomerizine, a prophylactic drug for migraine, as a potential anti-GBM drug from thousands of existing compounds. We investigated its therapeutic effects both in vitro and in vivo with the purpose of drug repositioning. Materials and method: Human patient-derived glioma stem cell line (KGS01, KGS10, KGS15), their differentiated cells, and GBM cell lines (A172, SNB19, T98, U87) were used. Proliferation assay, migration assay, invasion assay and sphere-forming assay were performed. We analyzed various signaling pathways altered by lomerizine by Western blotting. In addition, induction of apoptosis was evaluated by immunofluorescence and Annexin V assay. Anti-GBM effects of lomerizine in vivo with a mouse brain tumor model was validated Result: Lomerizine inhibited proliferation, migration, and invasion dose-dependently in all cell lines, especially in GSCs. Sphere formation was inhibited by lomerizine in all GSCs. STAT3, which is involved in tumorigenesis, was dephosphorylated after the treatment with lomerizine in a dose-dependent manner in all cell lines. Furthermore, lomerizine induced apoptosis in both immunofluorescence and Annexin V assay. In vivo experiments showed a significant tumor suppression and prolongation of overall survival in the group of mice treated with lomerizine.

CONCLUSION

Lomerizine has anti-GBM effects.

BIOM-20. IDENTIFICATION OF BLOOD BIOMARKERS FOR DIFFERENTIATING PSEUDOPROGRESSION FROM RECURRENCE IN GLIOBLASTOMA

After the initial treatment of glioblastoma, we occasionally encounter difficulty in distinguishing between pseudoprogression and recurrence. Observation without obtaining a pathological diagnosis is a common strategy in clinical practice. If the differentiation can be achieved easily, and reliably, early treatment can be introduced appropriately, leading to the benefits of early glioblastoma treatment. In this study, we attempted to identify blood biomarkers that help distinguish between recurrence and pseudoprogression. Blood samples were collected in 25 cases of primary glioblastoma, IDH wild type, at three time points: before treatment, after standard treatment: operation and temozolomide chemotherapy with concomitant radiation therapy, and when an enhancing lesion was recognized (21 cases of recurrence, 4 cases of pseudoprogression). Gelsolin (GSN), Apolipoprotein A-IV, Osteopontin, SERPINA3, ITIH2/4 Ceruloplasmin, LRG1, Collagen-1A2, which we previously extracted as diagnostic markers, using the comprehensive proteomics SWATH method, in blood samples of healthy volunteers and patients with glioblastoma (PLoS One. 2018, J Proteome Res. 2020), were analyzed. Absolute quantitative values of candidate molecules in the blood were obtained using a commercially available enzyme-linked immunoassay. Among the candidate molecules, GSN was significantly lower in pseudoprogression than in recurrence (p = 0.0032), and ROC analysis showed sensitivity of 95%, specificity of 100%, and an AUC = 0.98, which makes GSN a useful molecule to consider as a differential marker. We previously reported that GSN, actin binding protein, and inflammation markers are downregulated in glioblastoma (Cancer Sci. 2020). In summary, GSN was extracted as a candidate blood biomarker for the diagnosis of pseudoprogression. We are planning to validate the research with nationwide multi-institutional studies.

Tumor Microenvironment in Glioma Invasion

A major malignant trait of gliomas is their remarkable infiltration capacity. When glioma develops, the tumor cells have already reached the distant part. Therefore, complete removal of the glioma is impossible. Recently, research on the involvement of the tumor microenvironment in glioma invasion has advanced. Local hypoxia triggers cell migration as an environmental factor. The transcription factor hypoxia-inducible factor (HIF) -1α, produced in tumor cells under hypoxia, promotes the transcription of various invasion related molecules. The extracellular matrix surrounding tumors is degraded by proteases secreted by tumor cells and simultaneously replaced by an extracellular matrix that promotes infiltration. Astrocytes and microglia become tumor-associated astrocytes and glioma-associated macrophages/microglia, respectively, in relation to tumor cells. These cells also promote glioma invasion. Interactions between glioma cells actively promote infiltration of each other. Surgery, chemotherapy, and radiation therapy transform the microenvironment, allowing glioma cells to invade. These findings indicate that the tumor microenvironment may be a target for glioma invasion. On the other hand, because the living body actively promotes tumor infiltration in response to the tumor, it is necessary to reconsider whether the invasion itself is friend or foe to the brain.

Two different subcortical language networks supporting distinct Japanese orthographies: morphograms and phonograms

Language systems worldwide are based on either morphograms or phonograms, but Japanese is unique in that uses a complicated combination of kanji (morphogram) and kana (phonogram) characters. The white matter networks associated with reading have been investigated previously but remain incompletely understood. In this study, we performed intraoperative language mapping under local anesthesia and postoperative language assessments of 53 consecutive patients who underwent awake craniotomy for surgical resection of cerebral glioma within the dominant temporal or parietal lobe. Six cases showing intraoperative dyslexia elicited by direct electrical stimulation (DES) were examined, and all cases showed transient symptoms of kanji or kana dyslexia during DES. We investigated the intraoperative positive mapping points localized near four white matter bundles: the arcuate fascicle, posterior superior longitudinal fascicle, inferior fronto-occipital longitudinal fascicle, and inferior longitudinal fascicle (ILF). The intraoperative DES distributions for kanji dyslexia were especially associated with the anterior-inferior side of the ILF. On the other hand, the DES points associated with kana dyslexia were localized on the posterior-superior side of the complex composed of these four tracts. These results suggest the presence of specific non-interfering networks that subserve the processes of reading morphograms and phonograms.

ML-07 High expression of PD-L1 on tumor-associated macrophage is a predictive factor for favorable prognosis in PCNSL

PD-L1 and PD-L2 expression on tumor cells and tumor-infiltrating immune cells in primary central nervous system lymphoma (PCNSL) remains unclear. In the present study, we investigated the expressions of PD-L1 and PD-L2 in surgical specimens from needle biopsies and craniotomies to compare tumor tissue with surrounding tumor tissue (peritumoral tissue) and analyzed the correlation between expression of PD-L1/PD-L2 and survival in patients with PCNSL. We retrospectively analyzed the cases of 70 patients histologically diagnosed with PCNSL (diffuse large B-cell lymphoma). Immunohistochemistry for CD20, CD68, PD-L1, and PD-L2 was performed. In cases with specimens taken by craniotomy, the percentages of PD-L1- and PD-L2-positive macrophages were evaluated in both tumor and peritumoral tissue. The Kaplan-Meier method with log-rank test and Cox proportional hazard model were used for survival analysis. The tumor cells did not express very much PD-L1 and PD-L2, but macrophages expressed PD-L1 and PD-L2 in most of the patients. The median percentage of PD-L2-positive cells was significantly higher among peritumoral macrophages (32.5%; 95%CI: 0–94.6) than intratumoral macrophages (27.5%; 95%CI: 0–81.1, p=0.0014). There was a significant correlation between the percentages of PD-L2-positive intratumoral macrophages and PD-L2-positive peritumoral macrophages (p=0.0429), with very low coefficient correlation (ρ=0.098535). PD-L1 expression on macrophages was significantly associated with biological factors (intratumoral macrophages: better KPS, p=0.0008; better MSKCC score, p=0.0103; peritumoral macrophages: low proportion of LDH elevation, p=0.0064) and longer OS (for intratumoral macrophages: high PD-L1=60 months, 95%CI=30–132.6; low PD-L1=24 months, 95%CI=11–48; p=0.032; for peritumoral macrophages: high PD-L1=60 months, 95%CI=30.7-NR; low PD-L1=14 months, 95%CI=3–26). PD-L1 expression on peritumoral macrophages was strongly predictive of a favorable outcome (HR=0.30, 95%CI=0.12–0.77, p=0.0129). Macrophages in intratumoral and peritumoral tissue expressed PD-L1 and PD-L2 at a higher rate than tumor cells. PD-L1 expression, especially on peritumoral macrophages, seems to be an important prognostic factor in PCNSL.

TERT promoter mutation confers favorable prognosis regardless of 1p/19q status in adult diffuse gliomas with IDH1/2 mutations

TERT promoter mutations are commonly associated with 1p/19q codeletion in IDH-mutated gliomas. However, whether these mutations have an impact on patient survival independent of 1p/19q codeletion is unknown. In this study, we investigated the impact of TERT promoter mutations on survival in IDH-mutated glioma cases. Detailed clinical information and molecular status data were collected for a cohort of 560 adult patients with IDH-mutated gliomas. Among these patients, 279 had both TERT promoter mutation and 1p/19q codeletion, while 30 had either TERT promoter mutation (n = 24) or 1p/19q codeletion (n = 6) alone. A univariable Cox proportional hazard analysis for survival using clinical and genetic factors indicated that a Karnofsky performance status score (KPS) of 90 or 100, WHO grade II or III, TERT promoter mutation, 1p/19q codeletion, radiation therapy, and extent of resection (90-100%) were associated with favorable prognosis (p < 0.05). A multivariable Cox regression model revealed that TERT promoter mutation had a significantly favorable prognostic impact (hazard ratio = 0.421, p = 0.049), while 1p/19q codeletion did not have a significant impact (hazard ratio = 0.648, p = 0.349). Analyses incorporating patient clinical and genetic information were further conducted to identify subgroups showing the favorable prognostic impact of TERT promoter mutation. Among the grade II-III glioma patients with a KPS score of 90 or 100, those with IDH-TERT co-mutation and intact 1p/19q (n = 17) showed significantly longer survival than those with IDH mutation, wild-type TERT, and intact 1p/19q (n = 185) (5-year overall survival, 94% and 77%, respectively; p = 0.032). Our results demonstrate that TERT promoter mutation predicts favorable prognosis independent of 1p/19q codeletion in IDH-mutated gliomas. Combined with its adverse effect on survival among IDH-wild glioma cases, the bivalent prognostic impact of TERT promoter mutation may help further refine the molecular diagnosis and prognostication of diffuse gliomas.

Ependymoma with C11orf95-MAML2 fusion: presenting with granular cell and ganglion cell features

C11orf95-RELA fusion or, less frequently, YAP1 fusion is recurrently detected in most cases of supratentorial ependymoma. Other fusions have rarely been reported in some cases of supratentorial ependymoma, and little is known about their pathological or clinical features. Here, we present a case of supratentorial ependymoma with unusual pathological findings and C11orf95-MAML2 fusion. A 23-year-old man was admitted to our hospital because of headache and vomiting. Magnetic resonance imaging revealed a cystic lesion in the right frontal lobe, and gross total resection of the tumor was performed. Pathologically, the tumor was mainly composed of typical ependymal lesions with perivascular pseudorosettes and contained some atypical lesions, with granular and ganglion cell features. The tumor was diagnosed as anaplastic ependymoma, which was classified as grade III on the World Health Organization scale, and found to be RELA fusion-positive in the DNA methylation analysis. However, the tumor was negative for C11orf95-RELA fusion, and RNA sequencing detected C11orf95-MAML2 fusion. The patient has not received adjuvant therapy and has remained alive without any evidence of disease for 30 months, suggesting that the prognosis might be better than that of typical C11orf95-RELA fusion-positive ependymoma.

BIOM-21. CORRELATION BETWEEN EPHRIN-A2 EXPRESSION AND PROGNOSIS IN PATIENTS WITH GLIOBLASTOMA

The Eph receptor/ephrin ligand system is the largest family of tyrosine kinase with signaling modality through cell to cell adhesion. Eph/ephrin is involved in malignant phenotype such as cell proliferation, migration, and invasion in cancer cells. Although the functions of the Eph receptors in glioblastoma have been elucidated, little is known on ephrin ligands, especially ephrin-A2. Here, we analyze the expression of ephrin-A2 in gliomas using surgical specimens. The expression level of ephrin-A2 mRNA in 14 normal brains and glioma (WHO grade II 13, III 10, and IV 40) was measured by quantitative real-time PCR. Ephrin-A2 expression level was significantly lower in glioblastoma than in normal brain (p= 0.0127). When we divided the glioblastoma cases into high and low ephrin-A2 expression groups based on the median value, the overall survival (OS) was significantly longer in the high expression group compared with the low expression group (p= 0.034, median 24.0 and 14.0 months, respectively). Furthermore, multivariate analysis of factors related to OS with ephrin-A2 expression level and general prognostic factors (age, sex, preoperative KPS, surgical resection rate, radiochemotherapy, IDH1 mutation, MGMT promotor methylation) was performed. Ephrin-A2 expression level (p= 0.039), MGMT promotor methylation (p= 0.0001), and surgical resection rate (p= 0.017) were identified as independent prognostic factors. Taken together, ephrin-A2 is an independent favorable prognostic factor in glioblastoma.

RBPJ contributes to the malignancy of glioblastoma and induction of proneural-mesenchymal transition via IL-6-STAT3 pathway

Notch signaling plays a pivotal role in many cancers, including glioblastoma (GBM). Recombination signal binding protein for immunoglobulin kappa J region (RBPJ) is a key transcription factor of the Notch signaling pathway. Here, we interrogated the function of RBPJ in GBM. Firstly, RBPJ expression of GBM samples was examined. Then, we knocked down RBPJ expression in 2 GBM cell lines (U251 and T98) and 4 glioblastoma (GBM) stem-like cell lines derived from surgical samples of GBM (KGS01, KGS07, KGS10 and KGS15) to investigate the effect on cell proliferation, invasion, stemness, and tumor formation ability. Expression of possible downstream targets of RBPJ was also assessed. RBPJ was overexpressed in the GBM samples, downregulation of RBPJ reduced cell proliferation and the invasion ability of U251 and T98 cells and cell proliferation ability and stemness of glioblastoma stem-like cells (GSC) lines. These were accompanied by reduced IL-6 expression, reduced activation of STAT3, and inhibited proneural-mesenchymal transition (PMT). Tumor formation and PMT were also impaired by RBPJ knockdown in vivo. In conclusion, RBPJ promotes cell proliferation, invasion, stemness, and tumor initiation ability in GBM cells through enhanced activation of IL-6-STAT3 pathway and PMT, inhibition of RBPJ may constitute a prospective treatment for GBM.

Gelsolin inhibits malignant phenotype of glioblastoma and is regulated by miR-654-5p and miR-450b-5p

We have previously shown that gelsolin (GSN) levels are significantly lower in the blood of patients with glioblastoma (GBM) than in healthy controls. Here, we analyzed the function of GSN in GBM and examined its clinical significance. Furthermore, microRNAs involved in GSN expression were also identified. The expression of GSN was determined using western blot analysis and found to be significantly lower in GBM samples than normal ones. Gelsolin was mainly localized in normal astrocytes, shown using immunohistochemistry and immunofluorescence. Higher expression of GSN was correlated with more prolonged progression‐free survival and overall survival. Gelsolin knockdown using siRNA and shRNA markedly accelerated cell proliferation and invasion in GBM in vitro and in vivo. The inactive form of glycogen synthase kinase‐3β was dephosphorylated by GSN knockdown. In GBM tissues, the expression of GSN and microRNA (miR)‐654‐5p and miR‐450b‐5p showed an inverse correlation. The miR‐654‐5p and miR‐450b‐5p inhibitors enhanced GSN expression, resulting in reduced proliferation and invasion. In conclusion, GSN, which inhibits cell proliferation and invasion, is suppressed by miR‐654‐5p and miR‐450b‐5p in GBM, suggesting that these miRNAs can be targets for treating GBM.

Morphological characteristics of infected subdural hematoma: Comparison with images of chronic subdural hematoma

OBJECTIVES

Infected subdural hematoma (ISH) is a rare type of subdural empyema, with fewer than 50 cases reported to date. Its radiological features have not been adequately described, making diagnosis challenging. At our institution, two adults presented with ISH, which exhibited a characteristic shape on preoperative imaging.

PATIENTS AND METHODS

This study examined ISH cases and chronic subdural hematoma (CSH) cases that underwent surgery at the Ishikawa Prefectural Central Hospital between January 2016 and March 2018. To distinguish ISH from CSH, we focused on three specific radiological features: the biconvex shape of the hematoma, presence of a high-density region at the lower end of the hematoma on plain computed tomography (CT), and presence of a hyper-intense signal within the hematoma on diffusion weighted imaging (DWI).

RESULTS

We analyzed 30 ISH (current and previously reported) and 102 CSH cases in our study. We found no statistically significant associations between the hematoma type (ISH or CSH) and the presence of a high-density region at the lower end of the hematoma on plain CT (p = 0.13) or the presence of hyperintensity in the hematoma on DWI (p = 1.00). Conversely, a statistically significant association was found between the hematoma type and the biconvex shape of the hematoma (p < 0.01).

CONCLUSION

These results suggest that the shape of the hematoma on imaging provides valuable information that can be used to differentiate ISH from CSH and optimize therapeutic approaches.

PD-L1 and PD-L2 expression in the tumor microenvironment including peritumoral tissue in primary central nervous system lymphoma

Background

The prevalence of programmed death-ligand 1 (PD-L1) and PD-L2 expression on tumor cells and tumor-infiltrating immune cells in primary central nervous system lymphoma (PCNSL) remains unclear. In the present study, we analyzed needle biopsy and craniotomy specimens of patients with PCNSL to compare the PD-L1 and PD-L2 levels in the tumor and surrounding (peritumoral) tissue. We also assessed the correlation between biological factors and the prognostic significance of PD-L1 and PD-L2 expression.

Methods

We retrospectively analyzed the cases of 70 patients histologically diagnosed with PCNSL (diffuse large B-cell lymphoma). Immunohistochemistry for CD20, CD68, PD-L1, and PD-L2 was performed. In cases with specimens taken by craniotomy, the percentages of PD-L1- and PD-L2-positive macrophages were evaluated in both tumor and peritumoral tissue. The Kaplan-Meier method with log-rank test and Cox proportional hazard model were used for survival analysis.

Results

The tumor cells expressed little or no PD-L1 and PD-L2, but macrophages expressed PD-L1 and PD-L2 in most of the patients. The median percentage of PD-L2-positive cells was significantly higher among peritumoral macrophages (32.5%; 95% CI: 0–94.6) than intratumoral macrophages (27.5%; 95% CI: 0–81.1, p = 0.0014). There was a significant correlation between the percentages of PD-L2-positive intratumoral macrophages and PD-L2-positive peritumoral macrophages (p = 0.0429), with very low coefficient correlation (ρ = 0.098535). PD-L1 expression on macrophages was significantly associated with biological factors (intratumoral macrophages: better KPS, p = 0.0008; better MSKCC score, p = 0.0103; peritumoral macrophages: low proportion of LDH elevation, p = 0.0064) and longer OS (for intratumoral macrophages: high PD-L1 = 60 months, 95% CI = 30–132.6; low PD-L1 = 24 months, 95% CI = 11–48; p = 0.032; for peritumoral macrophages: high PD-L1 = 60 months, 95% CI = 30.7–NR; low PD-L1 = 14 months, 95% CI = 3–26). PD-L1 expression on peritumoral macrophages was strongly predictive of a favorable outcome (HR = 0.30, 95% CI = 0.12–0.77, p = 0.0129).

Conclusions

Macrophages in intratumoral and peritumoral tissue expressed PD-L1 and PD-L2 at a higher rate than tumor cells. PD-L1 expression, especially on peritumoral macrophages, seems to be an important prognostic factor in PCNSL. Future comprehensive analysis of checkpoint molecules in the tumor microenvironment, including the peritumoral tissue, is warranted.

Superficial Siderosis Associated with Long-Term Recurrence of Pilocytic Astrocytoma in an Elderly Person

BACKGROUND

Superficial siderosis is an irreversible disease in the central nervous system caused by the deposition of hemosiderin in the subpial tissue due to persistent bleeding in the subarachnoid space. The main symptoms include sensorineural hearing loss, cerebellar ataxia, and pyramidal tract disorder. Superficial siderosis is mainly idiopathic, but bleeding factors such as tumors or history of surgery often play an important role in its pathogenesis.

CASE DESCRIPTION

A 66-year-old man with a history of surgery for a cerebellar tumor 37 years ago complained of hearing loss. Magnetic resonance imaging showed recurrence of the tumor on T2-weighted images and hypointense areas along the cerebellar sulci on T2∗-weighted images. During the operation, microscopic bleeding was observed on the surface of the tumor. The pathologic diagnosis was pilocytic astrocytoma. A biopsy obtained during the first surgery revealed almost the same pathologic findings as those from a biopsy obtained during the second surgery, but the first specimen showed no hemosiderin deposition or active bleeding, which the second specimen did show.

CONCLUSIONS

Recurrent pilocytic astrocytoma with intratumoral hemorrhage was the suspected cause for superficial siderosis. The source of chronic bleeding was identified with intraoperative and pathologic findings. We describe the first report of superficial siderosis associated with a pilocytic astrocytoma that recurred 37 years after an initial tumor was excised.

CBMS-12 PENTAMIDINE; TRANSLATIONAL RESEARCH FOR A NEW CHEMOTHERAPY TARGETING ON GLIOMA CELLS AND GLIOMA STEM CELLS USING DRUG REPOSITIONING

INTRODUCTION

Glioblastoma (GBM) is primary malignant brain tumor with poor prognosis. Despite aggressive chemoradiotherapies, GBM has resistance and finally relapses. Recently, it is revealed that glioma stem cells (GSCs) are forming tumors and induce the recurrence. However, there is no effective therapy for GSCs. Herein, we newly identified pentamidine, an antiprotozoal drug, is effective for not only glioma cells but also GSCs by using drug repositioning approach.

METHOD

We used two glioma cell lines, A172 and T98, and patient-derived glioma stem cell lines KGS01, KGS07 which were established at Kanazawa University. We investigated proliferation ability, stemness and intracellular signal change by proliferation assay, sphere forming assay and western blotting, respectively. RESULT Proliferation ability was prohibited by pentamidine in both glioma cell lines and GSC lines. The half maximal inhibitory concentrations were 5–10 μM in glioma cell lines and 1–5 μM in GSC lines. Sphere forming assay revealed that size and number of spheres were reduced in both GSC lines, depending on concentration of pentamidine. In all cell lines, phosphorylation of extracellular signal-related kinase (ERK) and signal transducer and activator of transcription 3 (STAT3) were suppressed by pentamidine.

DISCUSSION

Pentamidine is known as the therapeutic drug for pneumocystis jirovecii. In this study, pentamidine suppressed proliferation activity in all cell lines, and stemness in both GSCs. Previous papers revealed pentamidine had anti-tumor effects for some types of tumor cell lines, however, therapeutic effect for tumor stem cells have never been mentioned.

CONCLUSION

These results suggest that pentamidine would be therapeutic drug for not only glioma cells but also GSCs by suppressing phosphorylation of ERK and STAT3.

Intratumoral continuous facial nerve stimulation for surgical resection of cystic vestibular schwannoma: Technical note

Background:

Cystic vestibular schwannomas (CVSs) account for about 10% of VS. The efficacy of continuous facial nerve stimulation (CFS) was previously reported; however, it is often difficult to place the electrode at the root exit zone (REZ) in the early stage of surgical resection. We proposed a new method of intratumoral CFS (ICFS) by searching for the facial nerve through the cyst wall and leaving the spherically shaped electrode at this point.

Methods:

The cyst wall was opened, and the ventral side of the tumor wall was stimulated to search for the positive point of facial nerve stimulation and place the spherically shaped electrode for continuous stimulation at this point through the cyst cavity (intensity: 0.2–1.5 mA, frequency: 1 Hz). Safe surgical resection could be performed under ICFS in all three cases.

Results:

Good preservation of the facial nerve and extent of resection that was estimated preoperatively was achieved in all cases.

Conclusion:

ICFS is suitable for the preservation of facial nerve function in surgical resection of CVS in cases in which electrode placement at the REZ is difficult.

Identification of Vortex Cores in Cerebral Aneurysms on 4D Flow MRI

BACKGROUND AND PURPOSE

The complexity and instability of the vortex flow in aneurysms are factors related to the rupture risk of unruptured cerebral aneurysms. We identified aneurysm vortex cores on 4D flow MR imaging and examined the relationship of these factors with the characteristics of cerebral aneurysms.

MATERIALS AND METHODS

We subjected 40 aneurysms (37 unruptured, 3 ruptured) to 4D flow MR imaging. We visualized streamlines with velocities below the threshold-that is, a percentage value of the aneurysm maximum inflow velocity-and progressively decreased the threshold to identify vortex cores as thin, streamline bundles with minimum velocities. Complexity and stability were compared in aneurysms with a smooth surface and those with blebs or daughter sacs.

RESULTS

The threshold for visualizing vortex cores ranged from 3% to 13% of the maximum inflow velocity. Vortex cores could be visualized in 38 aneurysms; in 2, they were not visualized through the cardiac cycle. A simple flow pattern (single vortex core) was identified in 27 aneurysms; the other 13 exhibited a complex flow pattern. The cores were stable in 32 and unstable in 8 aneurysms. Significantly more aneurysms with-than-without blebs or daughter sacs had a complex flow pattern (P = .006). Of the 3 ruptured aneurysms, 1 aneurysm had an unstable vortex core; in the other 2, the vortex core was not visualized.

CONCLUSIONS

The identification of vortex cores on 4D flow MR imaging may help to stratify the rupture risk of unruptured cerebral aneurysms.

DDIS-25. PENTAMIDINE; A NEW CHEMOTHERAPY TARGETING ON GLIOMA STEM LIKE CELLS

INTRODUCTION

Glioblastoma (GBM) is the most common primary malignant brain tumors. Despite aggressive therapies, median overall survival of patients who suffered from GBM is only 18 months. Furthermore, there is no effective therapy for glioma stem cells (GSCs), which act as forming tumors. Herein, we newly identified pentamidine, an antiprotozoal drug, is effective for GSCs by using drug repositioning approach.

METHOD

We used patient-derived glioma stem like cell lines KGS01, KGS07 which were established at Kanazawa University. We investigated proliferation ability, stemness and intracellular signal change by proliferation assay, sphere forming assay and western blotting, respectively. RESULT: Proliferation ability was prohibited by pentamidine in both cell lines. The half maximal inhibitory concentration was 1 - 5 μM. Sphere forming assay revealed that size and number of spheres were reduced in both cell lines, depending on concentration of pentamidine. Phosphorylation of extracellular signal-related kinase (ERK) and signal transducer and activator of transcription 3 (STAT3) were suppressed by pentamidine.

DISCUSSION

Pentamidine is known as the therapeutic drug for pneumocystis jirovecii. In this study, pentamidine suppressed proliferation activity and stemness in both glioma stem cell lines. Previous papers revealed pentamidine had anti-tumor effects for some types of tumor cell lines, however, therapeutic effect for tumor stem cells have never been mentioned.

CONCLUSION

These results suggest that pentamidine would be therapeutic drug for GSCs by suppressing phosphorylation of ERK and STAT3.

CBMT-18. THE ROLE OF BIOMARKER CANDIDATE GELSOLIN AND ITS MICRORNAS IN GLIOBLASTOMA

BACKGROUND

Among potential glioblastoma (GBM) blood biomarkers that we identified recently, we focused on gelsolin (GSN), a key regulator of actin filament disassembly. GSN was significantly lower in the blood of patients with GBM than in that of healthy controls. In this study, we analyzed the function of GSN and identified microRNAs (miRs) involved in GSN expression in GBM.

METHODS

QRT-PCR and western blot were introduced to evaluate the expression level of GSN in normal brain and GBM tissue. The localization of GSN was examined by immunohistochemistry and immunocytochemistry using human samples. The association between the expression level of GSN and progression free survival (PFS) /overall survival (OS) in GBM was assessed by Kaplan-Meier analysis. The function of GSN and its signal transduction in glioma cell lines were analyzed using small interfering RNA (siRNA) knockdown of GSN. Additionally, miRs controlling GSN expression were retrieved from databases of miRs, and miRs related to GSN expression were identified in GBM tissues.

RESULTS

The expression level of GSN was significantly lower in GBM tissues compared to normal brains. Normal astrocytes mainly expressed GSN. High expressor of GSN showed longer PFS and OS than low expressor. Proliferation and invasion in glioma cell lines were significantly promoted by siRNA for GSN accompanied with the activation of glycogen synthase kinase 3β. In GBM tissues, the expression levels of GSN and miR-654-5p, 450b-5p showed an inverse correlation. The inhibitor for miR-654-5p and miR-450b-5p accelerated GSN expression resulting reduction of proliferation.

CONCLUSION

GSN plays a role as suppressor of proliferation and invasion in GBM. miR-654-5p and miR-450b-5p which control GSN expression can be targets against GBM.

Enlargement of Langerhans cell histiocytosis of the hypothalamus with progression into the basal ganglia and white matter

Background

Langerhans cell histiocytosis (LCH) is a rare disease that may affect the central nervous system; it is caused by dendritic cell proliferation, and typically occurs in children. LCH frequently appears in the pituitary stalk and rarely results in multiple enhanced lesions in the brain parenchyma.

Case Description

We present a case of a 40-year-old woman who deveolped panhypopituitarism and central diabetes insipidus in the postpartum period requiring hormone replacement therapy. At first, magnetic resonance imaging only revealed thickening of the pituitary stalk; while 6 months later, a single enhanced mass lesion was detected in the hypothalamus. Another 5 months later, the lesion had enlarged with appearance of multiple, enhanced satellite lesions in the basal ganglia and white matter. The patient underwent successful craniotomy to obtain a biopsy sample; LCH of the hypothalamus was definitively diagnosis by histopathological examination. Steroids were administrated and resulted in significant reduction of all lesions.

Conclusions

Definitive histopathological diagnosis and subsequent appropriate therapy, such as steroid administration, are required when LCH lesions in the hypothalamus become progressively enlarged and new lesions appear in the brain parenchyma.

An Experience of Stereotactic Radiation Therapy for Primary Intracranial Choriocarcinoma

We report on a patient with choriocarcinoma in the pineal region who was successfully treated with stereotactic radiation therapy (SRT). The increased level of serum human chorionic gonadotropin (HCG) was lowered during chemotherapy with etoposide, cisplatin, and ifosfamide. However, HCG was not normalized and magnetic resonance images still showed an enhanced tumor mass with gadolinium. The patient underwent SRT of 40 Gy at an 80% isodose line per 10 fractions over'two weeks, followed by conventional craniospinal irradiation of 32.4 Gy. The level of HCG dropped below the detection limit. The patient has been in good condition for more than four years after the completion of treatment, without any signs of recurrence. We propose SRT as a valid treatment option for malignant germ cell tumors in the pineal region.

A case of a mobile choroid plexus cyst presenting with different types of obstructive hydrocephalus

Background

Although it is well known that most choroid plexus cysts (CPCs) are asymptomatic, previous studies have reported that they can infrequently cause progressive hydrocephalus along with their increasing sizes. Among those cases, some patients needed cyst fenestration or cerebrospinal fluid (CSF) diversion to recover neurological deterioration. Meanwhile, some CPCs revealed spontaneous resolution, and in rare cases, they developed re-accumulation. Some reports have described series of radiological findings about their changes in location.

Case Description

We present a 47-year-old male with CPC manifesting obstructive hydrocephalus. Radiological findings of the lateral and the third ventricles changed along with their different obstructive points, leading to their own symptoms. Because the patient's symptoms were not resolved completely, he underwent endoscopic fenestration for the cyst at the third ventricle. We could perform near-total resection, resulting in recovery of normal CSF flow. Postoperatively, the size of the ventricles decreased, with histological confirmation of a CPC. His symptoms resolved clearly without any complications.

Conclusions

It seems quite unusual that shift of the CPC location in the ventricle systems could induce not only different types of hydrocephalus but also their own symptoms. We need to consider that the location of CPCs might change when patients present with fluctuating symptoms over time.

Processable Poly(Keto-Imide)s Having Bulky Pendent Ether Groups

1, 3-Bis(3-aminobenzoyl)benzene (BAB), 1, 3-bis(3-amino-4-phenoxybenzoyl)benzene (BAPB) and 1, 3-bis(3-amino-4-biphenoxybenzoyl)benzene (BABB) were synthesized from 1, 3-bis(3-nitro-4-chlorobenzoyl)benzene. By using these three diamines and commercially available tetracarboxylic dianhydrides such as 3, 3′, 4, 4′-benzophenone tetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride (PMDA), several kinds of poly(keto-imide)s were synthesized. Thermal properties and processability such as melt-flowability and solubility in organic solvents of the obtained poly(keto-imide)s were investigated by focusing on the chemical structures of their repeating structure units. Inherent viscosities of poly(keto-imide)s ranged from 0.54 to 0.75 dl g−1. These poly(keto-imide)s displayed glass transition temperatures ( Tg) between 219 and 256 °C, and only the poly(keto-imide) prepared from BAB and PMDA showed a melting point ( Tm)at 451 °C. Melt-flowabilities of these poly(keto-imide)s except for BAB/PMDA poly(keto-imide) were observed between 285 and 330 °C. The poly(keto-imide)s having bulky pendent ether groups were soluble in chloroform, 1, 1, 2-trichloroethane, N, N-dimethylacetamide and m-cresol at ambient temperature.

Preparation and Properties of Novel Aromatic Polyimides from 5,7-Diamino-1,1,4,6-Tetramethylindan and Aromatic Tetracarboxylic Dianhydrides

Novel aromatic polyimides containing indan structure units were prepared from 5,7-diamino-1,1,4,6-tetramethylindan and various aromatic tetracarboxylic dianhydrides. The glass transition temperatures ( Tg’s) of these polyimides were not observed by differential scanning calorimetry at a temperature lower than 500 °C and the 5% weight loss temperatures ( Td5’s) of them were above 422 and 474 °C in air and nitrogen, respectively. Polyimide prepared from 5,7-diamino-1,1,4,6-tetramethylindan and 2,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride was soluble in organic solvents such as tetrahydrofuran, cyclopentanone, chloroform, acetone, ethyl acetate, N-methyl-2-pyrrolidinone and cresol at 20 wt% concentration at ambient temperature. The other resulting polyimides obtained from this diamine possessing an indan structure were also soluble in several organic solvents. These results indicated that polymer properties such as thermal behaviour and solubilities were influenced by the indan structure unit in a repeating structure.

Preparation and Properties of Optically Clear Poly[(Arylenedioxy)(Diphenylsilylene)]s and Poly[(Alkylenedioxy)(Diphenylsilylene)]

Several types of poly[(arylenedioxy)(diphenylsilylene)]s and poly[(alkylenedioxy)(diphenylsilylene)] were synthesized from various diols and dichlorodiphenylsilane by the step polymerization method. The thermal properties, solubility in organic solvents and optical properties of the obtained polymers were investigated by focusing on the chemical structures of their repeating structural units. The weight-average molecular weight ( Mw) of the obtained polymers based on polystyrene ranged from 43000 to 194000. High molecular weight, ductile materials with a high degree of optical clarity were obtained. These polymers display glass transition temperatures ( Tg) between 96 and 130°C. The obtained poly[(arylenedioxy) (diphenylsilylene)]s and poly[(alkylenedioxy)(diphenylsilylene)] were soluble in chloroform and toluene. The refractive index ( nd) was 1.64 for a biphenol-based poly[(arylenedioxy)(diphenylsilylene)] and 1.61 for a bisphenol-A based poly[(arylenedioxy)(diphenylsilylene)]. The poly[(arylenedioxy)(diphenylsilylene)]s and poly[(alkylenedioxy)(diphenylsilylene)] display very low birefringence (Δ n) between 0.0005 and 0.0022. The 70 μm thick film transmission of bicyclohexanol-based poly[(alkylenedioxy)(diphenylsilylene)] was 91% at a 350 nm wavelength.

Clinical outcome of endoscopic mucosal resection for esophageal squamous cell cancer invading muscularis mucosa and submucosal layer

When a tumor invades the muscularis mucosa and submucosal layer (T1a-MM and T1b in Japan), esophageal squamous cell cancer poses 10-50% risk of lymph node metastasis. By this stage of esophageal cancer, surgery, although very invasive, is the standard radical therapy for the patients. Endoscopic mucosal resection (EMR) is the absolutely curable treatment for cancer in the superficial mucosal layer. Because of its minimal invasiveness, the indications of EMR may be expanded to include the treatment of T1a-MM and T1b esophageal carcinoma. To date, the clinical outcomes of EMR for T1a-MM and T1b patients have not been fully elucidated. Here, the retrospective analysis of the clinical outcomes is reported. Between January 1994 and December 2007, 247 patients underwent EMR at Kanagawa Cancer Center. Of these individuals, 44 patients with 44 lesions fulfilled the following criteria: (i) extended EMR treatment for clinical T1a-MM and T1b tumor; (ii) diagnosis of clinical N0M0; and (iii) follow up for at least 1 year, and negative vertical margin. These patients were reviewed for their clinical features and outcomes. Statistical analyses were performed by the Kaplan-Meier methods, the Chi-square test, and the Cox proportional hazard model. P-value of <0.05 was considered statistically significant. The data were analyzed in February 2009. Based on the informed consent and their general health conditions, 44 patients decided the following treatments immediately after the EMR: 2 underwent surgery, 1 underwent adjuvant chemotherapy, and 41 selected follow up without any additional therapy. Of the 41 patients, 20 selected this course by choice, 12 because of severe concurrent diseases, 2 because of poor performance status, and 7 because of other multiple primary cancers. Twelve patients died; two were cause specific (4.5%), eight from multiple primary cancers, one from severe concurrent diseases, and one from unknown causes. No critical complications were noted. Median follow-up time was 51 months (12-126). Five patients ultimately developed lymph node metastasis. One patient with adjuvant chemotherapy required surgery, and another was treated with chemotherapy whose subsequent death was cause specific. The other three patients received chemoradiotherapy and have not shown cause-specific death. Overall and cause-specific survival rates at 5 years were 67.3% and 91.8%, respectively. Among 41 patients treated by EMR alone, only one died from primary esophageal cancer (2.4%), and overall and cause-specific survival rates at 5 years were 75.6% and 97.6%, respectively. Multivariate analysis revealed that severe concurrent diseases including multiple primary cancers and the administration of 5-fluorouracil-based chemotherapy for multiple primary cancers significantly influenced survival (P= 0.025, hazard ratio [HR] 13.1 [95% confidence interval 1.5-114]) and (P= 0.037, HR 0.213 [95% confidence interval 0.05-0.914]), respectively. Eight and six patients developed metachronous esophageal squamous cell cancer and local recurrence, respectively. With the exception of one patient, they could be retreated endoscopically. EMR is a reasonable option for the patients with T1a-MM and T1b esophageal carcinoma without clinical metastasis, especially for the individuals with severe concurrent diseases. The prognostic factors for the benefit of EMR in such cases should be further examined.

Long-term follow-up of periarterial sympathectomy for chronic digital ischaemia

This study investigates long-term clinical results (> 10 years) of periarterial sympathectomy in chronic ischaemic digits compared with intermediate-term results (3 years). Periarterial sympathectomy via the palm and volar wrist was carried out on 11 hands of seven patients with digital ischaemia but no gangrene or severe ulceration. The aetiology of ischaemia was Buerger's disease in four hands, collagen disease in three hands, and repetitive digital trauma in four hands. Subjective symptoms were evaluated at a mean follow-up period of 12 years. The efficacy of surgery was assessed objectively using thermography and plethysmography. Although five of seven patients continued on oral vasodilators and antiplatelet agents until the final follow-up, improvement of symptoms was maintained in all patients between intermediate- and long-term evaluations. Our results suggest that periarterial sympathectomy via the palm and wrist could prevent long-term aggravation of symptoms of chronic digital ischaemia when combined with adequate postoperative drug therapy.

Clinical outcome of endoscopic mucosal resection (EMR) in clinical stage I (cSt I ) esophageal cancer

e15569

Background: When a tumor invades to the muscularis mucosa or submucosal layer (T1a-MM or T1b, in Japan), cSt I esophageal cancer(EC) has 10–50%. risk of lymph node metastasis (LNM). Surgery, though very invasive, is the standard radical therapy for the patients(pts.) with such stage EC. Endoscopic mucosal resection (EMR), which conserves the esophagus, is a minimally invasive and attractive therapeutic modality for such pts. However, the clinical outcomes of EMR for these pts. have been not fully elucidated. Methods: We conducted retrospective analysis of the clinical courses of 44 pts. who underwent EMR for newly diagnosed T1a-MM or T1bcN0M0 EC between 1994 and 2007at our hospital, and who could be followed up for at least 1 year. Statistical analysis was performed by the Kaplan-Meier methods and the Cox proportional hazard model. Results: Patients decided on the following treatments immediately after EMR based on informed consent and their general condition; 2 underwent surgery, one underwent prophylactic chemotherapy(CHT) and 41 selected follow-up without any additional therapy. Of the 41, 20 selected this course by choice, 12 because of severe concurrent disease; 2 because of poor performance status and 7 because of other multiple primary cancers (MPCs). Twelve pts. died; 2 were cause specific; (4.5%), 8 from MPCs and, 2 from unknown causes. Median age was 67 years old (range 53–80), and 5 were female. No critical comlications were noted. Median follow-up time was 1542days (375–3786). 5 developed LNM. One with prophylactic CHT, was followed by surgery, and another was followed by CHT, who showed cause specific deaths later. Other 3 pts. followed by chemoradiotherapy, did not show cause specific death. Overall and cause specific survival rates at 5 years were 67.3% and 91.8%, respectively. Multivariate analysis revealed that either severe concurrent disease or MPCs significanctly influenced survival (p=0.041, HR 5.437(95%CI 1.073–25.542)). 8 and 6 pts. developed metachronous EC and local recurrence, respectively. Apart from one, they could be retreated endoscopicaly. Conclusions: EMR is a very useful therapeutic modality for cSt I EC, not only for local control but also as a clinically sufficient treatment; especially in pts. with severe concurrent disease.

No significant financial relationships to disclose.

Clear-cell adenofibroma can be a clonal precursor for clear-cell adenocarcinoma of the ovary: a possible alternative ovarian clear-cell carcinogenic pathway

Several studies have reported that ovarian clear-cell adenocarcinoma can be derived from endometriosis. Although the clear-cell adenofibroma (CCAF), a major form of benign and borderline ovarian clear-cell tumour, has been suggested as another precursor for clear-cell adenocarcinoma (CCA), there is no supportive genetic evidence for this presumption. To examine the genetic linkage between CCAF and CCA of the ovary, we conducted allelotype analysis for both CCAF and adjacent CCA components in 14 cases of CCA associated with benign CCAF and/or borderline CCAF. DNA isolated from laser-microdissected tissue was subjected to polymerase chain reaction and analysis for loss of heterozygosity (LOH), using 17 polymorphic markers located on 11 chromosomal arms: 1p, 5q, 8p, 9p, 9q, 10q, 11q, 13q, 18q, 19p and 22q. For all informative loci, the frequency of LOH in adenocarcinoma was 49% (54/110 loci), and was significantly higher than those in the components of benign CCAF (22%, 20/92 loci) and borderline CCAF (30%, 25/83 loci) (chi(2) test; p<0.05, respectively). The concordance rate in allelic patterns at all informative loci was 74% between benign CCAF and adenocarcinoma components, 81% between borderline CCAF and adenocarcinoma components, and 95% between benign CCAF and borderline CCAF components. Furthermore, between CCAF and adenocarcinoma components, an identical LOH pattern, involving the same alleles, was found in 13 (93%) of 14 cases at one or more chromosomal loci, and estimation of probability indicated that these events were very unlikely to have occurred by chance. Among the markers examined, LOHs on 5q, 10q and 22q were frequent in both CCAF and adenocarcinoma components, whereas LOHs on 1p and 13q were rare in CCAF components but frequent in adenocarcinoma components. These findings suggest that CCAF can be a clonal precursor for ovarian clear-cell adenocarcinoma.

Evaluation of significance of endoscopic mucosal resection (EMR) in early esophageal cancer

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Background: Radical surgery for esophageal cancer is very invasive. Endoscopic mucosal resection (EMR), which conserves the esophagus, is a minimally invasive and attractive therapeutic modality for early stage esophageal cancer. However, when the tumor reaches the deep mucosal or submucosal layer (“T1b” according to TNM classification), the incidence of lymph node metastasis (LNM) increases up to 10–50%. Therefore, the indications of EMR have to be clarified. Methods: Retrospective analysis was performed regarding the clinical course of 41 patients who were diagnosed as having cT1bN0M0 esophageal cancer and underwent EMR between 1994 and 2004 at our hospital. Statistical analysis was performed by the log-rank and Kaplan-Meier methods. Results: Thirty nine patients were selected and followed up without any additional therapy after obtaining written informed consent. Twenty patients (51%) had multiple primary cancers, 10 died, and 29 are still alive. MST of the dead patients was 22 months, and 7 of them (70%) died of advanced multiple primary cancers, while death was cause specific in only one case (due to LNM). The survival curves showed no significant differences between the patients with early multiple primary cancers and those without multiple cancers patients (MST = 72 months, p < 0.7784). In most of the dead patients and 23 of the surviving patients, the local lesion was well controlled without any recurrence. Conclusions: Many patients with early esophageal cancer who underwent EMR tended to die of multiple primary cancers. When the patient had early multiple primary cancers, the prognosis was not different from those without such cancer and the local lesion was well controlled. We concluded that EMR is a very useful therapeutic modality for local control as it is minimally invasive, especially in patients with multiple primary cancers.

No significant financial relationships to disclose.

Prognostic analysis of pulmonary adenocarcinoma subclassification with special consideration of papillary and bronchioloalveolar types

AIMS

The third edition of the World Health Organization (WHO) classification of lung tumours has been published and is expected to become the standard nomenclature. The aim of this study was to assess the usability and prognostic significance of the WHO classification in comparison with other recent classifications.

METHODS AND RESULTS

One hundred and forty-seven resected pulmonary adenocarcinoma cases were reviewed and histologically classified according to the WHO classification (1999) and the classification by Noguchi (1995). Papillary carcinomas as described by Silver and Askin (1997) were also identified. Since the papillary type in the WHO classification is not strictly defined, we compared the following two kinds of WHO classification: (i) WHO-N; WHO classification adopting Noguchi Type F as the definition of the papillary type, namely, pure papillary adenocarcinoma without a bronchioloalveolar component; (ii) WHO-SA; WHO classification adopting papillary carcinoma by Silver and Askin as the definition of the papillary type, namely, tumour with papillary structure constituting at least 75% of the lesion. The bronchioloalveolar carcinoma of the WHO classification showed a better prognosis than other subtypes in both overall and Stage I disease limited survival analysis. In analysis limited to Stage III disease, only the papillary type of WHO-SA showed a significantly worse prognosis.

CONCLUSIONS

WHO-SA is recommended for prognostic correlation.

The proximal form of mural thrombus in aortoiliac occlusive disease using computed tomography

BACKGROUND

It is important to know the nature of proximal thrombus in patients with aortoiliac occlusive disease (AIOD) when juxtarenal aortic clamping is scheduled. This study was aimed to evaluate the shape and nature of thrombi at several sites of the abdominal aorta in patients with AIOD using enhanced computed tomography (CT). Final judgment was made according to the operative findings.

METHODS

Between the years 1999 and 2001, 22 patients, who underwent aortobifemoral bypass, were enrolled. The shape and nature of their thrombi were examined at 4 points (superior mesenteric, suprarenal, juxtarenal and infrarenal arteries at the level of the 2 cm before the renal artery) and 88 slices of CT were examined retrospectively.

RESULTS

There was mural thrombus in 31 slices, which could be classified into 4 shapes (crescent-shaped: 10 cases; magatama: 2; wavy: 12; circular: 6). The wavy and circular shaped thrombi were found to be atheromatous. Nine cases (40.9%) on operative findings were atheroma (wavy: 4; circular shaped: 5). The crescent shape might correspond to fibrin thrombus. Atheromatous thrombus clamping near the renal artery was thought to cause microthromboembolism to surrounding organs.

CONCLUSIONS

It is recommended that the more proximal aorta or splanchnic arteries should be temporarily clamped during proximal procedures in patients with wavy or circular shaped thrombi at the juxtarenal aorta to prevent kidney or bowel infarction.