Discovery of Gut-Restricted Small-Molecule Inhibitors of Intestinal Sodium-Dependent Phosphate Transport Protein 2b (NaPi2b) for the Treatment of Hyperphosphatemia

NaPi2b is primarily expressed in the small intestine, lungs, and testes and plays an important role in phosphate homeostasis. The inhibition of NaPi2b, responsible for intestinal phosphate absorption, is considered to reduce serum phosphate levels, making it a promising therapeutic approach for hyperphosphatemia. Using a novel phosphate uptake inhibitor 3 (IC50 = 87 nM), identified from an in-house compound collection in human NaPi2b-transfected cells as a prototype compound, we conducted its derivatization based on a Ro5-deviated strategy to develop orally administrable small-molecule NaPi2b inhibitors with nonsystemic exposure. Consequently, compound 15, a zwitterionic compound with a potent in vitro phosphate uptake inhibitory activity (IC50 = 64 nM) and a low membrane permeability (Pe < 0.025 × 10-6 cm/s), was developed. Compound 15 showed a low bioavailability (F = 0.1%) in rats and a reduction in phosphate absorption in the rat intestinal loop assay comparable to sevelamer hydrochloride, a clinically effective phosphate binder for treating hyperphosphatemia.

P–721 Probability of receiving assisted reproductive technology treatment through out-of-pocket payment and household income: A discrete choice experiment in Japan

Study question

What is the probability that patients will receive assisted reproductive technology (ART) treatment based on their out-of-pocket payment and income class?

Summary answer

Higher-income patients opted for ART even at a higher cost, whereas an out-of-pocket payment was the most influential determinant in all income groups.

What is known already

Economic disparities affect access to ART treatment in many countries. At the time of this survey, Japan provided partial reimbursement for ART treatment exclusively for those in low- or middle-income classes due to limited governmental budgets. However, the optimal financial support by income class is unknown.

Study design, size, duration

We conducted a discrete choice experiment (DCE) in Japan in January 2020 including 824 women with fertility problems who were recruited via an online social research panel.

Participants/materials, setting, methods

Participants included women aged 25–44 years undergoing fertility diagnosis or treatment. They completed a DCE questionnaire including 16 hypothetical scenarios, created by orthogonal design, to measure six relevant ART attributes (pregnancy rate, risk of adverse effects, number of visits to outpatient clinics, consultation hours, kindness of staff, and out-of-pocket expense) and their relation to treatment choice. We used mixed-effect logistic regression models to estimate the probability of receiving ART treatment for each attribute.

Main results and the role of chance

Of the 1,247 eligible women recruited, 824 completed the survey (66% participation rate). All six attributes significantly influenced treatment preference, with participants valuing out-of-pocket payment the most, followed by pregnancy rates and kindness of staff. The odds ratios of each attribute to receiving ART treatment were 0.58 (95% confidence interval [CI]: 0.57 − 0.59) for out-of-pocket payments per additional 100,000 Japanese yen (JPY; i.e., 800 euros), 1.47 (95% CI: 1.43 − 1.53) for pregnancy rates per additional 5%, and 4.16 (95% CI: 3.73 − 4.64) for kindness of staff, after adjusting for clinical and socioeconomic factors. Significant interactions occurred between high household income (≥8 million JPY) and high out-of-pocket payment (≥500,000 JPY). However, the mean predicted probability of the highest-income patients (i.e., ≥10 million JPY) to receive ART treatment at the average cost without public funding (i.e., 400,000 JPY) was 47% (interquartile range: 18%−76%), whereas that of middle-income patients (i.e., 6–8 million JPY) to receive ART at the average subsidized cost (i.e., 100,000 JPY) was 60% (interquartile range: 33%–88%).

Limitations, reasons for caution

Other attributes not included in our DCE scenarios might be relevant in real-life settings. Choices made in a DCE would not wholly match the actual treatment choices.

Wider implications of the findings: The present DCE suggested that out-of-pocket payment was the primary determinant in patients’ ART decisions. High-income patients were more likely to receive ART treatment even at a high cost, but their ineligibility for government financial support due to their high income might discourage them from receiving treatment.

Trial registration number

NA

Development of Dihydrodibenzooxepine Peroxisome Proliferator-Activated Receptor (PPAR) Gamma Ligands of a Novel Binding Mode as Anticancer Agents: Effective Mimicry of Chiral Structures by Olefinic E/ Z-Isomers

A novel class of PPARγ ligand 1 (EC₅₀ = 197 nM) with a dibenzoazepin scaffold was identified through high-throughput screening campaign. To avoid the synthetically troublesome chiral center of 1, its conformational analysis using the MacroModel was conducted, focusing on conformational flip of the tricyclic ring and the conformational restriction by the methyl group at the chiral center. On the basis of this analysis, scaffold hopping of dibenzoazepine into dibenzo[ b, e]oxepine by replacing the chiral structures with the corresponding olefinic E/ Z isomers was performed. Consequently, dibenzo[ b, e]oxepine scaffold 9 was developed showing extremely potent PPARγ reporter activity (EC₅₀ = 2.4 nM, efficacy = 9.5%) as well as differentiation-inducing activity against a gastric cancer cell line MKN-45 that was more potent than any other well-known PPARγ agonists in vitro (94% at 30 nM). The X-ray crystal structure analysis of 9 complexed with PPARγ showed that it had a unique binding mode to PPARγ ligand-binding domain that differed from that of any other PPARγ agonists identified thus far.

Development and Performance Evaluation of Planar Travel Distance Sensors for Mobile Robots in Sandy Terrain

A planar travel distance sensor (two-dimensional sensor) was developed for a mobile robot in sandy terrain. The sensor system uses an optical flow device integrated into a small module with a simple configuration. The system achieves a high sampling rate on the order of milliseconds as well as precise measurement on a sub-millimeter order. Its performance was evaluated experimentally for measurement accuracy and repeatability, velocity response, robustness at varied heights with respect to terrain, and terrain surface characteristics. The experimental results confirm that the two-dimensional sensor system is accurate, having an error of distance traveled of less than a few percent, and that it possesses a wide dynamic range for the robot’s traveling velocity. This paper also discusses the applicability of the two-dimensional sensor for practical scenarios on the basis of the experimental findings.

Highly sensitive fluorescence detection of metastatic lymph nodes of gastric cancer with photo-oxidation of protoporphyrin IX

BACKGROUND

The establishment of a precise and rapid method to detect metastatic lymph nodes (LNs) is essential to perform less invasive surgery with reduced gastrectomy along with reduced lymph node dissection. We herein describe a novel imaging strategy to detect 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence in excised LNs specifically with reduced effects of tissue autofluorescence based on photo-oxidation of PpIX. We applied the method in a clinical setting, and evaluated its feasibility.

METHODS

To reduce the unfavorable effect of autofluorescence, we focused on photo-oxidation of PpIX: Following light irradiation, PpIX changes into another substance, photo-protoporphyrin, via an oxidative process, which has a different spectral peak, at 675 nm, whereas PpIX has its spectral peak at 635 nm. Based on the unique spectral alteration, fluorescence spectral imaging before and after light irradiation and subsequent originally-developed image processing was performed. Following in vitro study, we applied this method to a total of 662 excised LNs obtained from 30 gastric cancer patients administered 5-ALA preoperatively.

RESULTS

Specific visualization of PpIX was achieved in in vitro study. The method allowed highly sensitive detection of metastatic LNs, with sensitivity of 91.9% and specificity of 90.8% in the in vivo clinical trial. Receiver operating characteristic analysis indicated high diagnostic accuracy, with the area under the curve of 0.926.

CONCLUSIONS

We established a highly sensitive and specific 5-ALA-induced fluorescence imaging method applicable in clinical settings. The novel method has a potential to become a useful tool for intraoperative rapid diagnosis of LN metastasis.

Development of pancreatic cancers during long-term follow-up of side-branch intraductal papillary mucinous neoplasms

BACKGROUND AND STUDY AIMS

Side-branch intraductal papillary mucinous neoplasms (SB-IPMNs), and associated synchronous and metachronous pancreatic cancers are increasingly detected as imaging modalities become more sensitive. We investigated the natural history of SB-IPMN, and the incidence and characteristics of pancreatic cancers among patients undergoing long-term follow-up.

PATIENTS AND METHODS

We reviewed the clinical, imaging, and pathological features in 103 patients, diagnosed at the Aichi Cancer Center between September 1988 and September 2006 as having SB-IPMN, and conservatively followed up for ≥ 2 years (median 59 months) based on an endoscopic ultrasonography (EUS) database.

RESULTS

74 (71.8 %) patients had nonprogressive lesions. Overall, six patients (5.8 %) developed pancreatic cancers during follow-up, with intraductal papillary mucinous (IPM) carcinoma in four, and ductal carcinoma of pancreas that was not IPMN in two patients. Of the six pancreatic cancers, five were diagnosed at a resectable stage. The 5-year and 10-year actuarial rates of development of pancreatic cancer were 2.4 % and 20.0 %, respectively. Although, at the last follow-up, cyst size, main pancreatic duct (MPD) diameter, mural nodule size, and frequency of metachronous and/or synchronous cancers of other organs were significantly higher in patients who developed IPM carcinoma, resected SB-IPMNs without mural nodules and dilated MPDs had no IPM carcinomas.

CONCLUSIONS

The frequency of pancreatic cancers is high on long-term follow-up of SB-IPMN. Although conservative management is appropriate for selected patients, regular and long-term imaging, especially by EUS is essential, even if SB-IPMN remains unchanged for 2 years. Presence of mural nodule and dilated MPD seem to be more appropriate indicators for resection than cyst size alone for SB-IPMNs.

Clinical impact of intraoperative histological examination of the ductal resection margin in extrahepatic cholangiocarcinoma

Background

Although ductal resection margin status in extrahepatic cholangiocarcinoma is evaluated by intraoperative histological examination of frozen sections, its clinical relevance remains controversial.

Methods

Material taken from patients who underwent R0 or R1 resection for extrahepatic cholangiocarcinoma with intraoperative histological examination of the final ductal resection margins between 1994 and 2003 were reviewed. The following histological classification was used: insufficient, negative for malignancy (NM), undetermined lesion (UDL) or positive for malignancy (PM). Multivariable analyses of overall survival and anastomotic recurrence in relation to ductal margin status were performed.

Results

Resection material from 363 patients was identified. For the proximal ductal margin, only PM in intramural lesions was significantly associated with poor survival (hazard ratio (HR) 1·72, 95 per cent confidence interval (c.i.) 1·06 to 2·74) and anastomotic recurrence (HR 6·39, 95 per cent c.i. 1·89 to 21·62) compared with NM. In analysis of overall survival according to distal ductal margin status, the HRs for UDL and PM lesions in comparison with NM were not significant.

Conclusion

PM in intramural lesions found during intraoperative histological examination of the proximal ductal resection margin was related to clinical outcome. This finding favours additional resection of the bile duct. A similar association was not found for histology results of the distal resection margin.

Endoscopic submucosal dissection for colorectal tumors: technical difficulties and rate of perforation

BACKGROUND AND STUDY AIM

Endoscopic submucosal dissection (ESD) for colorectal tumors is not generally recommended because of the technical difficulties and complications, including perforation. These aspects of ESD are thoroughly analyzed in our retrospective study.

PATIENTS AND METHODS

We studied 105 colorectal tumors, from 100 patients, that were treated by ESD at the Kyoto Prefectural University of Medicine or Nara City Hospital between 2005 and 2008. We analyzed tumor size, operation time, rate of en bloc resection, and complications. In addition, we thoroughly investigated the cases of perforation.

RESULTS

The average tumor size was 30.4 mm; average operation time, 102 min; and rate of en bloc resection, 88.5 %. Perforation occurred in 10.4 % of the ESD procedures. Of the 11 perforations, 8 were detected during ESD and treated by clip closure during endoscopy, while 3 were evident only on subsequent routine computed tomography (CT); these were also managed conservatively. A case of postoperative hemorrhage was also observed.

CONCLUSIONS

ESD effectively achieved a high rate of en bloc resection. However, the perforation rate was substantial; hence, improvement in the ESD method is required. The outcomes of ESD, especially for early colorectal malignancies, need to be assessed further.

Continuous remission in an infant with chest wall malignant rhabdoid tumor after relapse

Malignant rhabdoid tumor (MRT) is a highly aggressive tumor that occurs in infancy or childhood. The prognosis, especially in infants, is very poor. Here we report the long-term survival of a 5-month-old boy with MRT that arose from the chest wall. After total resection of the tumor, the patient was given 4 cycles of doxorubicin, vincristine, and cyclophosphamide, alternating with ifosfamide and etoposide. After 18 months off therapy, he had a local recurrence at the same site. After a second total resection, he was given additional chemotherapy with 30.6-Gy local irradiation. No further recurrence has been observed for 5 years since the second complete remission. Currently, he is alive and well at 7.5 years post-onset. Our experience in this case suggests a fundamental strategy of successful treatment of this highly malignant pediatric tumor: (1) complete resection of the localized tumor, (2) intensive multiagent chemotherapy for the minimal disseminated disease, and (3) radiotherapy for local control of the disease.

New POMT2 mutations causing congenital muscular dystrophy: identification of a founder mutation

BACKGROUND

Dystroglycanopathies are a group of congenital muscular dystrophies (CMDs) with autosomal recessive inheritance, often associated with CNS and ocular involvement. They are characterized by the abnormal glycosylation of alpha-dystroglycan, and caused by mutations in at least six genes encoding enzymes: FKTN, POMGNT1, POMT1, POMT2, FKRP, and LARGE. POMT2 mutations have recently been identified in Walker-Warburg syndrome and in a milder muscle-eye-brain disease-like form.

METHODS

We studied mentally retarded patients with CMD, analyzed POMT2 by sequencing the coding regions, and also performed a haplotype analysis in all patients and their family members carrying the new POMT2 mutation.

RESULTS

We report three novel POMT2 mutations. One of these, p.Tyr666Cys, was homozygous in two unrelated patients and in a compound heterozygous state in others. All patients showed severe diffuse muscle weakness, microcephaly, severe mental retardation, and marked lordoscoliosis with hyperextended head. Elevated CK levels, cerebral cortical atrophy, and cerebellar vermis hypoplasia were constant findings. Mild cardiac abnormalities, focal white matter abnormalities, or partial corpus callosum hypoplasia were detected in single cases. Eye involvement was absent or mild. By genotype analysis, we defined a distinct 170kb haplotype encompassing POMT2 and shared by all the subjects harboring the mutation p.Tyr666Cys.

CONCLUSIONS

Our results broaden the clinical spectrum associated with POMT2 mutations, which should be considered in patients with CMD associated with microcephaly, and severe mental retardation with or without ocular involvement.

Solitary myofibroma of the lumbar vertebra: adult case

We present the first known adult case of solitary myofibroma of bone, which affected a lumbar vertebra in a 33-year-old male. Radiography identified a purely lytic lesion with a sclerotic rim in the right pedicle of L1. CT showed an expansile lytic lesion with a sclerotic rim. MRI of the lesion revealed an isointense signal on T1-weighted images, an inhomogeneously hyperintense signal on T2-weighted images, and marked enhancement with gadolinium. Pathological study showed a mixed picture of nodular proliferation of spindle-shaped myoid cells and hemangiopericytomatous proliferation of short spindle/small round cells. The tumor cells were immunoreactive for smooth muscle actin and immunonegative for desmin. This case of solitary myofibroma of bone is exceptionally rare because of its occurrence in an adult older than 20 years of age and its location at an extra-craniofacial site.

Frequent loss of RUNX3 gene expression in remnant stomach cancer and adjacent mucosa with special reference to topography

Our previous studies suggest that a lack of RUNX3 function is causally related to the genesis and progression of human gastric cancer. This study was conducted to determine whether alteration of RUNX3 gene expression could be detected in the normal-looking gastric remnant mucosa, and to ascertain any difference in the potential of gastric carcinogenesis between the anastomotic site and other areas in the remnant stomach after distal gastrectomy for peptic ulcer (RB group) or gastric cancer (RM group), by analysing RUNX3 expression with special reference to topography. A total of 89 patients underwent distal gastrectomy for gastric cancer from the intact stomach (GCI group) and 58 patients underwent resection of the remnant stomach for gastric cancer (RB group: 34 cases, RM group: 24 cases). We detected RUNX3 and gene promoter methylation by in situ hybridisation, quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), and methylation-specific PCR. The interval between the initial surgery and surgery for remnant gastric cancer (interval time) was 10.4 years in the RM group, and 27.5 years in the RB group. Cancers in the RB group were significantly more predominant in the anastomosis area (P<0.05). Within the tumour, downregulation of RUNX3 expression ranged from 74.7 to 85.7% in the three groups. The rate of downregulation of RUNX3 of adjacent mucosa was 39.2% (11 in 28 cases) in RB and 47.6% (10 in 21 cases) in RM, which are significantly higher than that of the GCI group (19.5%, 17 in 87 cases). In noncancerous mucosa of the remnant stomach in the RB group, RUNX3 expression decreased more near the anastomosis area. In the RM group, however, there were no significant differences in RUNX3 expression by sampling location. Based on RUNX3 downregulation and clinical features, residual stomach mucosa of the RM group would have a higher potential of gastric carcinogenesis compared to the RB or GCI group. Gastric stump mucosa of the RB group has higher potential especially than other areas of residual stomach mucosa. Measurement of RUNX3 expression and detection of RUNX3 methylation in remnant gastric mucosa may estimate the forward risk of carcinogenesis in the remnant stomach.

Extended intestinal metaplasia. A survey of 1392 gastrectomies from dwellers of the Pacific basin

BACKGROUND

To assess the extent of gastric intestinal metaplasia (IM) in gastrectomy specimens in populations of the Pacific basin having different incidence of gastric carcinoma.

MATERIALS AND METHODS

One thousand three hundred and nine-two gastrectomies were investigated: 1088 had a gastric carcinoma and 304 miscellaneous gastric diseases. Twenty-one thousand three hundred and fourteen histological sections were reviewed under low-power (4X). IM was either spotty (SIM) or extended (EIM= encompassing one or more entire low-power fields/section). Widespread IM (WIM) was regarded as EIM if present in > or =5 histological sections.

RESULTS AND CONCLUSION

The percent of gastrectomies harboring a carcinoma increased significantly with increasing age more notably in those with diffuse carcinomas (DC) than in those with intestinal carcinomas (IC). The percent of gastrectomies with EIM was significantly higher in specimens with IC than with DC, particularly among elderly patients, and in specimens from countries with a high cancer incidence. The percent of gastrectomies with WIM was higher in specimens having IC than in those having DC. Migration per se did not influence the frequency of specimens with EIM in elderly Japanese patients: Japanese migrants to Hawaii had a similarly high frequency of EIM as those dwelling in Japan. Japanese patients with a gastric carcinoma showed atypical mitoses in areas with EIM far from the tumor, suggesting that cellular mutation(s) play a role in the evolution of EIM towards gastric dysplasia and carcinoma in that ethnic group. The drawback of gastric biopsies in assessing the extent of gastric intestinal metaplasia and, thereby, estimating possible cancer risk in long-term studies has been stressed.

Total synthesis of ecteinascidin 743

The total synthesis of ecteinascidin 743 (1), an extremely potent antitumor agent, has been accomplished. The synthesis features Ugi's 4CC reaction, intramolecular Heck reaction, phenol-aldehyde cyclization, and acid-induced intramolecular sulfide formation.

Mental stress and physical exercise increase platelet-dependent thrombin generation

Thrombin generation is an important factor in the pathogenesis of thrombogenic disorders and acute coronary syndromes. Increase in mental stress has been associated with the initiation of the acute coronary syndromes, but the exact mechanism is not known. The present study examined the effects of physical exercise and mental stress on platelet-dependent thrombin generation. Twelve healthy men (mean age 34.2 +/- 2.4 years) underwent a treadmill exercise test and a mental stress test by performing mental arithmetic. Platelet-dependent thrombin generation and plasma concentrations of catecholamines, thrombin-antithrombin III complex (TAT), plasmin-alpha2 plasmin inhibitor complex (PIC), and plasminogen activator inhibitor-1 (PAI-1) were measured before, immediately after, and at 10 and 30 min after stress. Thrombin generation increased significantly immediately after exercise, followed by rapid normalization. Mental stress caused a significant increase in thrombin generation 10 min after stress. While plasma concentrations of epinephrine, norepinephrine, and dopamine were elevated immediately after exercise, and rapidly returned to baseline, only plasma norepinephrine increased immediately after mental stress. TAT and PIC concentrations did increase immediately after exercise; however, PAI-1 remained unchanged. The increase in thrombin generation with exercise and mental stress was unaffected by treatment with 81 mg/day of aspirin of 7 days. However, it was inhibited by a single oral 40-mg dose of metoprolol. Both exercise and mental stress cause an increase in platelet-dependent thrombin generation, which was suppressed by beta-blocker therapy, but not by aspirin.

[Discharge planning for home care]

The department of medical social work and discharge planning was established in the University of Tokyo hospital to ensure that patients would receive proper care at a right place. The discharge planning team consists of a physician, a medical social worker and a home care coordinator. The home care coordinator, who coordinates with the home nursing station and the primary care physician, is effective for advance of home care. The role of the home care coordinator is to relieve patients of their anxiety about home care. As a result, the number of home care patients has gradually increased.

Proliferative activity of intrahepatic colorectal metastases after preoperative hemihepatic portal vein embolization

Although hemihepatic portal vein embolization (PVE) has been used preoperatively to extend indications for hepatectomy in patients with colorectal metastases, the effects of this procedure on tumor growth and outcome remain controversial. To address this issue, we assessed the proliferative activity of intrahepatic metastases after PVE and the long-term outcome of this procedure. Eighteen patients with colorectal metastases underwent preoperative PVE between 1996 and 2000 (PVE group). Twenty-nine patients who underwent major hepatic resection without PVE served as control (non-PVE group). The hepatic parenchymal fraction of the left lobe had significantly increased from 38.1 +/- 3.2% to 45.9 +/- 2.9% 3 weeks after PVE (+20.5%, P <.0001). Tumor volume and percent tumor volume had also significantly increased from 223 +/- 89 mL to 270 +/- 97 mL (+20.8%, P =.016) and from 13.7 + 4.3% to 16.2 + 4.9% (+18.5%, P =.014), respectively. There was no apparent correlation between the increase in parenchymal volume and that in tumor volume. The Ki-67 labeling index of metastatic lesions was 46.6 +/- 7.2% in the PVE group and 35.4 +/- 12.6% in the non-PVE group (P =.013). Long-term survival was similar in the PVE and non-PVE groups, however, disease-free survival was significantly poorer in the PVE group than in the non-PVE group (P =.004). We conclude that PVE increases tumor growth and probably is associated with enhanced recurrence of disease. Although PVE is effective in extending indications for surgery, patient selection for PVE should be cautious.

Prognostic Factors and Therapeutic Strategy for Anaplastic Carcinoma of the Thyroid

Although anaplastic thyroid carcinoma (ATC) is one of the most aggressive malignancies, a few patients survive for a fairly long time after modern intensive treatment. We tried to identify prognostic factors of ATC to assist in deciding on the proper therapeutic strategy in individual patients. Of 47 patients with ATC (1976-1999), 3 patients with "incidental" ATC (largely differentiated thyroid carcinoma with a small region of ATC) were excluded because they had a favorable outcome. The 1-year survival rate of the remaining 44 patients with clinically distinct ATC was 16%. The presence of acute symptoms, large tumor (> 5 cm), distant metastasis, and leukocytosis (white blood cell count > or = 10,000/mm3) proved to be significant risk factors. Multivariate analysis by the Cox proportional hazard model showed that these four factors were independent factors for predicting death from ATC. We devised a novel prognostic index (PI) based on the number of these four unfavorable characteristics the patient possessed. Patients with a PI of < or =1 had a 62% survival rate at 6 months, whereas no patients with a PI of > or =3 survived longer than 6 months. All patients with a PI of 4 died from their disease within 3 months. Nine patients received multimodal treatment with a combination of surgery, external irradiation, and chemotherapy and had a long survival (mean 333 +/- 68 days; one patient is still alive and tumor-free), with a mean PI of 0.6. Our PI is useful as a means of selecting patients for aggressive therapy. When the PI is low, multimodal treatment should be attempted to obtain the best survival results; if it is high most patients are too seriously ill to tolerate intensive treatment and palliative therapy is recommended.

Genetic alterations and growth pattern in biliary duct carcinomas: loss of heterozygosity at chromosome 5q bears a close relation with polypoid growth

Biliary duct carcinomas (BDCs) are relatively rare and the carcinogenic mechanisms underlying their induction are poorly understood. There are two growth patterns, polypoid and non-polypoid infiltrative type, but little information is available concerning the relation between growth pattern and genetic alterations. A comparative study was therefore conducted to clarify if differences in genetic changes, including loss of heterozygosity (LOH) at 5q, 9p, 17p, and 18q, and K-ras mutations exist between polypoid and non-polypoid infiltrative type BDCs. LOH analysis was performed using microsatellite markers and K-ras point mutations were analysed by dot blot hybridisation. The incidences of changes for polypoid and non-polypoid infiltrative types were 73% and 26% on 5q, 63% and 59% on 9p, 55% and 50% on 17p, and 20% and 18% on 18q, and 25% and 27% for K-ras mutations. Most importantly, we found the frequency of 5qLOH to be significantly higher with polypoid growth than in the non-polypoid infiltrative type (p<0.05), especially in extrahepatic duct carcinomas (p<0.05). The incidences of other genetic alterations (LOH at 9p, 17p, and 18q, and K-ras mutations) showed similar rates with both tumour types. The present data suggest that 5qLOH may have a close relation with polypoid growth in BDCs.

Role of esophagectomy in treatment of esophageal carcinoma with clinical evidence of adjacent organ invasion

With carcinoma of the thoracic esophagus, clinical evidence of invasion of adjacent organs (T4) indicates a highly advanced stage, and most surgeons avoid esophagectomy. Although the therapeutic strategy for such disease is generally selected based on preoperative evaluation and intraoperative inspection, their accuracy and the relation to survival outcomes after esophagectomy have seldom been analyzed on the basis of exact histopathologic evidence. We performed esophagectomy, with perioperative adjuvant therapy when possible, on patients with clinical-T4 tumors unless absolutely unresectable conditions were detected. Among the 500 patients who underwent esophagectomy, the 78 patients whose tumors were confirmed to be T4 pathologically were compared with patients whose tumors were assessed as T4 preoperatively or intraoperatively to evaluate the role of esophagectomy for clinical-T4 carcinoma. Esophagectomy was possible for 99% of the pathologic-T4 tumors preoperatively assessed as resectable, but the resection was grossly incomplete in 35%. The true-positive rates in tumors preoperatively and intraoperatively assessed as T4 were 51% and 84%, respectively. The hospital mortality rate in patients with pathologic-T4 tumors was 4%. The overall 5-year survival rate for patients with pathologic-T4 tumors was 14%, compared with 60% for those with tumors assessed as T4 intraoperatively but not pathologically. Esophagectomy with perioperative adjuvant therapy yielded occasional cure with an acceptable mortality rate for patients with pathologic-T4 tumors assessed as technically resectable. Preoperative assessment and intraoperative macroscopic inspection had limitations for predicting pathologic-T4 disease and incomplete resection. Only patients with definitive evidence of unresectability should be excluded from esophagectomy.

Thallium-201 single photon emission computed tomography (SPECT) in patients with duchenne's progressive muscular dystrophy: a histopathologic correlation study

The pathomorphologic mechanism responsible for abnormal perfusion imaging during thallium-201 myocardial single photon emission computed tomography (201Tl-SPECT) in patients with Duchenne's progressive muscular dystrophy (DMD) was investigated. Hearts from 7 patients with DMD were evaluated histopathologically at autopsy and the results correlated with findings on initial and delayed resting 201Tl-SPECT images. The location of segments with perfusion defects correlated with the histopathologically abnormal segments in the hearts. Both the extent and degree of myocardial fibrosis were severe, especially in the posterolateral segment of the left ventricle. Severe transmural fibrosis and severe fatty infiltration were common in segments with perfusion defects. In areas of redistribution, the degree of fibrosis appeared to be greater than in areas of normal perfusion; and intermuscular edema was prominent. Thus, the degree and extent of perfusion defects detected by 201Tl-SPECT were compatible with the histopathology. The presence of the redistribution phenomenon may indicate ongoing fibrosis. Initial and delayed resting 201Tl-SPECT images can predict the site and progress of myocardial degeneration in patients with DMD.

Acute effects of cigarette smoking on platelet-dependent thrombin generation

AIMS

Thrombin is an important factor in the pathogenesis of thrombotic diseases. To clarify whether smoking has an effect in platelet-dependent thrombogenesis, we studied the acute effects of smoking on platelet-dependent thrombin level in smokers.

METHODS AND RESULTS

Subjects consisted of ten smokers and nine non-smokers. Platelet-dependent thrombin level measured after overnight fasting was greater in smokers than in non-smokers (smokers vs non-smokers, 121 +/- 47 vs 56 +/- 5 mIU. ml(-1), P < 0.01). When subjects in the smokers group smoked two cigarettes containing 0.9 mg of nicotine per cigarette, platelet-dependent thrombin levels showed a transient three-fold increase in blood samples obtained immediately after smoking (365+/-76 mIU. ml(-1), P < 0.001). Thrombin levels in the blood samples obtained 10 min and 30 min after smoking were less than that in the samples obtained immediately after smoking ceased, but were not significantly different from those in the samples obtained before smoking. Blood nicotine level increased significantly immediately after smoking (P < 0.001), and plasma protein C activity decreased significantly 30 min after smoking (P < 0.05). When nicotine or cotinine was added to the platelet-rich plasma of non-smokers ex vivo, the platelet-dependent thrombin level increased significantly (P < 0.002).

CONCLUSION

Platelet-dependent thrombin level is enhanced in smokers, even when not smoking, when compared with non-smokers and increases immediately after smoking. Increases in nicotine and cotinine levels caused by smoking induced a prothrombotic state in smokers via increased platelet-dependent thrombogenesis.

[mRNA detection of beta-myosin heavy chain gene in the autopsy cases of hypertrophic cardiomyopathy]

A known trigger of sudden cardiac death, hypertrophic cardiomyopathy (HCM) is associated with a point mutation in or overexpression of MYH7, which encodes the sarcomere protein beta-myosin heavy chain. We used nested RT-PCR to detect MYH7 mRNA in left ventricular myocardial tissue. We extracted total RNA from tissue samples that had been obtained after autopsy of 8 people who had died from HCM-related sudden death and that had been fixed in 10% formalin solution for as long as 4 years. The abundance of total RNA extracted from the 100 mg samples of cardiac muscle ranged from 10 to 24 mg/ml. The products of the nested RT-PCR were electrophoresed on a denaturing 8% polyacrylamide gel, and the MYH7 mRNA product was detected as a 424 bp band. MYH7 mRNA was easier to detect in tissue that had been fixed for shorter rather than longer periods. In addition, the greater the cardiac weight, the higher was the yield of the MYH7 mRNA product. Although mRNA had been detected by using RT-PCR on formalin-fixed paraffin-embedded tissue, no one previously had identified by using RT-PCR or nested RT-PCR on formalin-fixed tissue. By using nested RT-PCR, we were able to detect MYH7 mRNA in myocardial tissue that had been fixed in formalin solution for 4 years. Our results are applicable to retrospective examination into the cause of death in cases of sudden cardiac failure.

Skin metastasis from the spindle cell component in rectal carcinosarcoma

Carcinosarcomas are rare tumors, which are usually composed of carcinomatous areas close to or intermixed with sarcomatous components. Only 6 cases of carcinosarcoma of the colon have been reported in the English literature previously. We describe the 7th case, an 82-year-old man with a skin metastasis from the spindle cell component of a rectal carcinosarcoma. On rectal exploration, a large, firm tumor was palpated 2 cm from the anal verge. Endoscopic examination revealed a tumor projecting into the lumen, and hemorrhage from the tumor surface. We performed a low anterior resection. The resected specimen contained an ulcerative lesion with a round wall in continuity with a papillary tumor. Carcinoma and sarcoma components existed concomitantly along with transitional features. Immunohistochemistry disclosed immunoreactivity for vimentin in most of the spindle cell areas. Carcinoembryonic antigen was positive in the adenocarcinomatous component. One month after surgery, the patient developed a skin metastasis on the back. The skin biopsy specimen contained proliferating spindle cells almost identical to those of the primary lesion. The patient died of carcinosarcoma 6 months after surgery. In this paper, we review 7 cases of colorectal carcinosarcoma, including our patient, who is only the 7th such reported case.

Localization of initial lymph node metastasis from carcinoma of the thoracic esophagus

BACKGROUND

Most surgeons consider esophageal carcinoma with lymph node involvement a systemic disease. However, it is possible that the disease may be localized in the earlier phases of lymphatic metastasis. The distribution of involved lesions in the initial phase of lymph node metastasis has not been thoroughly investigated yet.

METHODS

Among 329 patients that underwent curative (R0 International Union Against Cancer [UICC]) esophagectomy with systematic mesoesophageal dissection, 51 cases of patients with only 1 involved lymph node (solitary involvement) were retrospectively investigated and compared with patients with multiple involved lymph nodes. The regional lymph nodes were divided into the thoracocervical junction group (lower deep cervical and recurrent nerve lymph nodes), perigastric group, and intrathoracic group.

RESULTS

Lymph node involvement was limited to a solitary lymph node in 46% of lymph node positive patients with esophageal carcinoma confined to the wall (T1 and T2, UICC) and in 17% of lymph node positive patients with cancer that invaded the extramural layer (T3 and T4, UICC). Of patients with solitary involvement, 82% had a positive thoracocervical junction or perigastric lymph node. The 5-year survival rate in solitary involvement cases was 61%, and 65% when solitary involvement was not intrathoracic. Most of the 5-year survivors had involvement of a thoracocervical junction or perigastric lymph node and had not received systemic chemotherapy.

CONCLUSIONS

Solitary involvement was not rare and not directly associated with a disseminated disease. Solitary involvement was commonly located in the thoracocervical junction or abdomen that are accessible without thoracotomy. Systematic dissection of the regional lymph nodes including thoracocervical junction and perigastric groups is recommended for resectable esophageal carcinoma at this time. However, less extensive dissection may be performed in selected cases if the sentinel lymph node concept proves valid.

Clinical significance of hypoxemia without congestive heart failure in patients presenting with acute myocardial infarction

This study investigated the clinical significance of hypoxemia without apparent clinical congestive heart failure in patients with acute myocardial infarction (AMI). Sixty-two patients with AMI of the Killip group I and Forrester subset I state were stratified into a hypoxemia group and a normoxemia group. The increase in the neutrophil count and the severity of the coronary artery disease as graded by Gensini's score were significantly higher in the hypoxemic group. The cardiac index was lower in hypoxemic than normoxemic patients. Myocardial scintigraphy revealed no acute difference in defect scores (DS) or left ventricular ejection fraction (LVEF) between the two groups, but DS was significantly higher (p < 0.01) and LVEF was lower (p < 0.01) in the hypoxemic group 2 years after infarction. Patients with hypoxemia have a more severe angiographic coronary pathology than normoxemic patients, and latent cardiac hypofunction occurs.

Origin of giant cells in osteoclast-like giant cell tumors of the pancreas

To clarify the origin of giant cells in osteoclast-like giant cell tumors (OGCTs) of the pancreas, we performed microscopical, immunohistochemical, and K-ras gene mutation analyses with a microdissection approach in 3 cases, featuring 4 cellular components (osteoclast-like giant cells [OGCs], pleomorphic large cells [PLCs], mononuclear cells, and ductal carcinoma cells). Two cases had abundant OGCs, and 1 case contained large number of both OGCs and PLCs. In each, none of the microdissected OGCs contained any K-ras gene mutation while they were positive for a histiocytic marker (CD-68). In contrast, PLCs, when present, frequently harbored K-ras gene mutations and were negative for CD-68. In all cases, mononuclear cells, a mixture of histiocyte-like and atypical, from microscopic and immunohistochemical viewpoints, also frequently showed K-ras alteration. Histiocyte-like mononuclear cell was equipped with a regular and oval nucleus similar to those in OGCs and was positive for CD-68. Atypical mononuclear cell showed an irregular, pleomorphic, or sometimes bizarre nucleus similar to those in PLCs and was negative for CD-68. All of the K-ras gene mutations found in PLCs and mononuclear cells were the same as in the ductal carcinoma cells within the same tumor. Thus, OGCs differ in origin from ductal cells and are strongly suggested to be nonneoplastic and of mesenchymal origin, whereas PLCs, which harbor K-ras gene mutations, are neoplastic and presumably derived from ductal carcinoma cells. Moreover, mononuclear cells may be classified into 2 types, histiocyte-like and atypical.

Unrecognizable intramucosal spread of diffuse-type mucosal gastric carcinomas of less than 20 mm in size

BACKGROUND

Diffuse-type intramucosal gastric carcinomas sometimes spread within the mucosa beyond their macroscopic margins, often causing positive resection margins upon local resections such as endoscopic mucosal resection.

PATIENTS AND METHODS

A consecutive series of 34 patients with solitary, small (less than 20 mm in diameter macroscopically), and macroscopically well demarcated diffuse-type mucosal carcinomas, who were treated with gastrectomy followed by detailed pathological examination, were included in the present study. Unrecognizable intramucosal spread is defined as an area of cancer which is indistinguishable macroscopically from its peripheral noncancerous area, and covered by normal epithelium with neither morphologic nor color changes. We examined the extent of unrecognizable intramucosal spread, measuring the maximum distances between macroscopic and microscopic margins on the sections, and investigated its relationship with four factors: location of the lesion, macroscopic size, histologic ulcer formation, and degree of atrophy of the background mucosa.

RESULTS

The maximum distance between macroscopic and microscopic margins was significantly larger (maximum 10 mm) in the background mucosas with marked atrophy than in those with little or no atrophy. No other factors, including location, macroscopic size and ulcer formation, correlated with it.

CONCLUSION

We should pay particular attention to unrecognizable intramucosal spread, especially in markedly atrophied mucosa, when treating small diffuse-type mucosal gastric cancer by local resections such as endoscopic mucosal resection. In addition, because of unrecognizable intramucosal spread, a surgical incision margin of at least 10 mm from the macroscopic margin is indicated.

K-ras gene mutations and loss of heterozygosity at the p53 gene locus relative to histological characteristics of mucin-producing tumors of the pancreas

Mucin-producing tumors (MPTs) of the pancreas accompanied by carcinomas usually include various grades of dysplasia in the ductal epithelium, and invasive areas are histologically similar to those of common invasive ductal carcinomas, suggesting that MPTs provide a good tool to investigate early stages of pancreatic carcinogenesis. Thus, to clarify genetic alterations in the early stage of pancreatic carcinogenesis, we analyzed K-ras gene mutations and loss of heterozygosity (LOH) at the p53 gene locus using 37 cases of MPTs harboring dysplastic epithelium. Further, we conducted an extended, multifocal microdissection analysis focusing on the histological features of ductal epithelium and the distribution of genetic alterations for 3 cases of MPT positive for LOH of the p53 gene to determine the relation to tumor progression. K-ras gene mutations were detected with high frequency in 50% or more cases of the adenomas (14 of 19), borderline tumors (4 of 7), and carcinomas (8 of 11), whereas LOH of the p53 gene was limited to carcinomas (3 of 5 informative cases, 60%) and always accompanied by K-ras gene mutation. Investigation of a total of 126 microdissection sites from 3 cases showed the presence of K-ras gene mutations in mild dysplasia and all (100%) regions of moderate or more marked dysplasia, whereas LOH of the p53 gene showed more gradual tendency to increase with grade from moderate dysplasia. In addition, the multifocal genetic analysis showed K-ras gene mutations to be widely distributed throughout tumors, whereas LOH of the p53 gene was localized to 1 or a few areas. Further, topographically delimited areas with the same histology in the same tumor did not always show the same genetic alteration. In conclusion, we could confirm that both the K-ras and p53 gene alterations occur in the intraductal stage of MPT, and the latter is superimposed on the former during the course of tumor progression. However, the pattern of association of histological features with genetic alteration differs from tumor to tumor.

The prognosis of intraductal papillary mucinous tumors of the pancreas

BACKGROUND/AIMS

Intraductal papillary mucinous tumors of the pancreas have been recognized as a distinct clinical entity. However, their biological behavior has not been clearly defined. The aim of this study was to examine the prognosis of this tumor, to clarify the biological behavior and determine the most appropriate treatment.

METHODOLOGY

Correlations between prognosis of operated cases and histopathologic features were investigated.

RESULTS

In 105 patients with characteristic clinical features of intraductal papillary mucinous tumors, the lesions were classified as hyperplasias in 21%, intraductal tumors in 48% and invasive carcinomas in 31%. Minimal invasion was apparent in 25%, lymph node metastasis in 21%, and fistula formation in 31% of the invasive lesions. Non-invasive and minimally invasive intraductal papillary mucinous tumors were essentially free from risk of tumor recurrence. Other invasive intraductal papillary mucinous tumors showed a significantly poor prognosis.

CONCLUSIONS

Because of the variation in pathological characteristics, patient outcome and the possibility of differential diagnosis, the treatment might be recommended as follows: the case of hyperplasia can be followed-up with close surveillance. Non-invasive and minimally invasive intraductal papillary mucinous tumors should be operated with function-preserving minimal pancreatectomy. For patients with invasive intraductal papillary mucinous tumors evident with preoperative imaging modalities, radical operations with lymph node dissection might be needed.

The role of exercise radionuclide angiocardiography in predicting future cardiac events in patients with acute myocardial infarction

Left ventricular ejection fraction (LVEF) during exercise radionuclide angiocardiography is a useful prognostic index for patients with acute myocardial infarction (AMI). However, most previous studies were performed before reperfusion therapies (i.e., thrombolysis and coronary angioplasty) were widely used. Therefore, because reperfusion therapy has become a standard therapeutic option, we reexamined the prognostic value of rest LVEF and exercise LVEF determined by radionuclide angiocardiography in patients with AMI at the time of hospital discharge.

METHODS

The retrospective analysis included 419 consecutive patients with AMI who underwent ergometric stress radionuclide angiocardiography before hospital discharge, 44 +/- 14 d after the onset of AMI.

RESULTS

During a mean follow-up of 4.6 y, cardiac events occurred in 101 (24.1%) patients. Cardiac events included recurrent MI (33 patients, 7.9%), unstable angina (49 patients, 11.7%), congestive heart failure (16 patients, 3.8%), and ventricular tachycardia (3 patients, 0.7%). The LVEF at peak exercise was significantly lower in the group with cardiac events (P = 0.0140). However, no significant difference was observed in the rest LVEF between patients with and without cardiac events. On the basis of multivariate analysis using a Cox proportional hazards model, only peak LVEF (P = 0.0246) was found to be an independent predictor of cardiac events. In the patient subsets with a peak LVEF >50% or <50%, the event-free rate was 81.0% versus 62.4% (P = 0.0007), respectively. Regardless of the presence or absence of reperfusion therapy, the lower peak LVEF was associated with a decrease in the event-free survival rate.

CONCLUSION

In the current reperfusion era, the lower peak LVEF as measured by radionuclide angiocardiography at the time of discharge is a useful predictor of subsequent cardiac events in patients with AMI.