老年急性心肌梗塞心率变异时域分析

目的分析急性心肌梗塞（ＡＭＩ）后老年患者心率变异（ＨＲＶ）时域指标，了解ＡＭＩ后ＨＲＶ变化。方法以多单位协作方式对１５７例ＡＭＩ后２周的老年患者行动态心电图检测ＨＲＶ时域法５项指标，并与健康老年组对比分析。数据经ＥｐｉＩｎｆｏ（６．０）统计软件处理。结果①ＡＭＩ患者的正常Ｒ－Ｒ间期标准差（ＳＤＮＮ）、平均值的标准差（ＳＤＡＮＮ）和标准差的平均值（ＳＤＮＮＩｎｄｅｘ）低于对照组（Ｐ＜０．０１），而相邻正常Ｒ－Ｒ间期差值的均方根（ＲＭＳＳＤ）和相邻正常Ｒ－Ｒ差值大于５０ｍｓ记数占总Ｒ－Ｒ间期数的百分比（ＰＮＮ５０）虽低于对照组，但无显著差异（Ｐ＞０．０５）。②ＡＭＩ后ＨＲＶ时域５项指标男、女性别间无显著性差异（Ｐ＞０．０５）。③ＳＤＮＮ、ＳＤＡＮＮ和ＳＤＮＮＩｎ－ｄｅｘ在心肌梗塞各部位间无显著差异（Ｐ＞０．０５），ＲＭＳＳＤ和ＰＮＮ５０前间壁低于下壁心肌梗塞（Ｐ＜０．０５）。结论老年人ＡＭＩ后ＨＲＶ降低。反映交感神经活性的ＳＤＮＮ、ＳＤＡＮＮ和ＳＤＮＮＩｎｄｅｘ和反映迷走神经活性的ＲＭＳＳＤ和ＰＮＮ５０２组指标变化不相同。     

冠心病患者心率变异向量长度和角度指数的非线性分析

应用动态心电图（ＡＥＣＧ）系统记录心率变异性（ＨＲＶ），并经非线性分析的定量指标向量长度指数（ＶＬＩ）和向量角度指数（ＶＡＩ）研究了３２例冠心病（ＣＨＤ）、２０例陈旧性心肌梗死患者和３９例健康人。结果表明：正常对照组Ｐｏｉｎｃａｒｅ散点图呈慧星状占９０％（３５／３９）；陈旧性心肌梗死（ＯＭＩ）组呈鱼雷状占８０％（１６／２０）；而ＣＨＤ组多表现为散点图变短、变窄、角度变小。ＶＬＩ值ＣＨＤ、ＯＭＩ组与对照组分别为１４８．７±３０．３，１２４．０±２７．３和１９７．０±３８．２（Ｐ＜０．０１）。ＶＡＩ值三组分别为０．５４±０．１４，０．４２±０．１５和０．８５±０．１８（Ｐ＜０．０１）。ＳＤ、ＰＮＮ５０、ｒＭＳＳＤ以及左心室舒张功能在ＣＡＤ、ＯＭＩ组也有相应变化。我们认为，非线性分析ＶＬＩ、ＶＡＩ定量指标可为ＣＨＤ提供重要信息。     

尿激酶溶栓治疗对急性心肌梗塞范围的影响

７６例发病≤６ｈ的急性心肌梗塞（ＡＭＩ）患者随机分为两组，根据常规心电图初始ＳＴ段的抬高预计和最后ＱＲＳ改变估计心肌梗塞范围（ＭＩＳ），观察尿激酶对ＭＩＳ的影响。结果表明：ＭＩＳ在对照组治疗前后差异无显著性意义（Ｐ＞０．０５）；在尿激酶组治疗前后差异有显著性意义（Ｐ＜０．０１）；两组ＭＩＳ变化百分比差异有显著性意义（Ｐ＜０．０１）。其中尿激酶组未通亚组治疗前后ＭＩＳ差异无显著性意义（Ｐ＞０．０５），再通亚组治疗前后ＭＩＳ差异有显著性意义（Ｐ＜０．０１）。在两组未通病例中ＭＩＳ变化百分比差异有显著性意义（Ｐ＜０．０５）。提示尿激酶溶栓治疗可显著减少ＭＩＳ。挽救缺血濒死的心肌，这一效果在冠状动脉（冠脉）再通的病例中尤为突出，对冠脉未通病例也有一定作用。     

溶栓治疗对急性心肌梗塞后左室容量及功能的影响

９６例首次急性心肌梗塞（ＡＭＩ）患者随机分为尿激酶溶栓治疗组与常规治疗组，采用超声心动仪检测的左室容量（ＥＳＶ、ＥＤＶ）及左室功能（ＥＦ、ＲＷＭＩ）的变化以探讨溶栓治疗对ＡＭＩ后左室容量及功能的影响。结果表明溶栓治疗可使左室容量明显减少（ＥＳＶ，Ｐ＜０．０００１；ＥＤＶ，Ｐ＜０．００５），左室功能明显改善（ＥＦ，Ｐ＜０．００５；ＲＷＭＩ，Ｐ＜０．０２）。在梗塞部位上，前壁优于下壁，晚期治疗与早期治疗效果相同，青年患者较老年患者治疗效果更加明显。     

心肌梗塞及再灌注治疗对左室结构的影响

本文利用二维超声心动图对心肌梗塞及再灌注治疗对心室结构的形响作了观察，结果显示急性心肌梗塞（ＡＭＩ）和陈旧心肌梗塞（ＯＭＩ）患者左室容积明显增大（Ｐ＜０．０５和Ｐ＜０．０１），但ＯＭＩ患者较ＡＭＩ患者更明显（Ｐ＜０．０５）。ＡＭＩ患者溶栓成功组左室收缩末容积（ＥＳＶ）小于非溶栓者，ＯＭＩ患者曾成功溶栓者在室ＥＳＶ和舒张末容积（ＥＤＶ）均小于非溶栓者（Ｐ＜０．０５）。     

急性心肌梗塞患者体内维生素E与脂质过氧化的关系

检测１２例急性心肌梗塞（ＡＭＩ）、２１例冠心病（ＣＡＤ）和２０例正常对照（ＮＳ）的血清维生素Ｅ（ＶｉｔＥ）、人超氧化物岐化酶（ｈＳＯＤ－１）及血浆过氧化脂质（ＬＰＯ）的代谢产物之一丙二醛（ＭＤＡ）水平。结果显示ＡＭＩ组的ＭＤＡ水平明显高于ＣＡＤ及ＮＳ组，而ＶｉｔＥ水平则显著低于ＣＡＤ及ＮＳ组，二者呈显著负相关（γ＝－０．６７，Ｐ＜０．００１）；ＡＭＩ和ＣＡＤ组的ｈＳＯＤ－１水平均明显低于ＮＳ组，但其两组间无差异，提示ＡＭＩ时ＶｉｔＥ作为主要的抗氧化剂被大量消耗，可能是ＡＭＩ发展的原因之一。     

早期应用卡托普利对急性心肌梗塞后左室容积和功能的影响

本文对６５例急性心肌梗塞（ＡＭＩ）患者随机分为卡托普利组３３例，服用卡托普利（１２．５ｍｇ，ｔｉｄ）；安慰剂组３２例，服用安慰剂。两组均在服药后第１周和第１、２、３个月各做一次二维超声心动图检查。结果：卡托普利组左室收缩末期容积指数（ＬＶＥＳＶＩ）降低（Ｐ＜０．０５），舒张末期容积指数（ＬＶＥＤＶＩ）无显著改变，每搏量指数（ＳＶＩ）和射血分数（ＥＦ）增加（均Ｐ＜０．０５）；安慰剂组ＬＶＥＤＶＩ和ＬＶＥＳＶＩ增加，ＥＦ降低（均Ｐ＜０．０５）。两组比较，至服药后第３个月，上述各指标差异均显著（Ｐ＜０．０５）。     

系列电药理研究筛选有效抗折返性室上性心动过速药物的临床意义

对６７例折返性室上性心动过速（ＲＳＶＴ）施行以单一抗心律失常药物（ＡＡＤ）为基础、异丙肾上腺素（Ｉｓｏ）和美托洛尔（Ｍｅｔ）为辅助的系列电药理研究（ＳＥＰＳ）（简称ＡＩＭ－ＳＥＰＳ）。结果表明，Ｉｓｏ能使普罗帕酮和莫雷西嗪的抗ＲＳＶＴ总有效率分别降低６６．７％～８０．０％和２０．０％，该效应能被Ｍｅｔ所抵消。随访资料提示，对于选择预防ＲＳＶＴ临床复发有效的长期口服ＡＡＤ，ＡＩＭ－ＳＥＰＳ明显优于单一ＡＡＤ的电药理研究。     

急性心肌梗塞后左室重构变化的研究

应用二维多普勒超声心动图对６８例急性心肌梗塞（ＡＭＩ）患者的左室重构（ＬＶＲ）变化进行了观察。结果显示，心肌梗塞后ＬＶＲ早期（３～６周）左室舒张末内径（ＬＶＤｄ）、左室舒张末容积（ＥＤＶ）、左室收缩末容积（ＥＳＶ）、左室收缩期最大室壁应力（Ｅｄｂ）、左室收缩末期室壁应力（Ｅｓｂ）、平均室壁应力（ｍｅａｎｂ）、二尖瓣舒张晚期血流速度峰值（ＰＶＡ）、左房张力（ＬＡＴ）、左房射血力（ＬＡＦ）及峰值充盈速度（ＰＦＲ）显著增大（Ｐ＜０．０１－０．００１），射血分数（ＥＦ）、心输出量（ＣＯ）、左室收缩期圆周指数（ＬＶＳＣＩ）、平均周边纤维缩短速率（ＭＶＣＦ）、二尖瓣舒张早期血流速度峰值（ＰＶＥ）及ＰＶＡ／ＰＶＥ显著降低（Ｐ＜０．０１－０．００１）。ＬＶＲ晚期（６－１２个月），ＥＤＶ、ＥＳＶ增加，ＥＦ、ＣＯ及ＬＶＳＣＩ降低（Ｐ＜０．００１）；与ＬＶＲ早期比较，ＰＶＥ、ＰＶＡ及ＬＡＦ无显著性差异（Ｐ＞０．０５）。提示ＡＭＩ后ＬＶＲ的主要病因是梗塞区膨展、左室扩张、容量负荷及室壁应力增加，从而导致心肌梗塞并发症；ＥＳＶ、ＥＤＶ及ＥＦ可作为了解远期ＡＭＩ患者预后的最佳指标。     

老年心肌缺血者QTc和QTcd变化及临床意义

测定了６４例老年心肌缺血（ＭＩＳ）患者和２１例心肌梗塞（ＭＩ）患者心电图的ＱＴｃ间期和ＱＴｃ离散度（ＱＴｃｄ），并与心血管神经官能症（ＣＶＮ）及正常老年人进行比较；探讨ＱＴｃ、ＱＴｃｄ与致命性室性心律失常（ＦＶＡ）、心原性猝死（ＣＳＤ）的关系；分析ＭＩ不同部位的ＱＴｃｄ变化以及稳定性心绞痛（ＳＡＰ）和不稳定性心绞痛（ＵＳＡＰ）的ＱＴｃｄ差异。结果：老年女性患者ＱＴｃ较男性长（Ｐ＜０．０５），而ＱＴｃｄ两者无差异；老年ＭＩＳ患者ＱＴｃ和ＱＴｃｄ较正常组明显延长（Ｐ＜０．０１）；ＭＩ前壁、下壁和后壁３组ＱＴｃｄ无明显差异（Ｐ＞０．０５）；ＵＳＡＰ患者ＱＴｃｄ较ＳＡＰ长（Ｐ＜０．０５）。     

High dose rate brachytherapy in the treatment of oral cancer--the preliminary one institution experience

Low dose rate brachytherapy is well established treatment modality of oral cancer. Data about high dose rate brachytherapy (HDR BT) are still scarce with heterogenous results. The aim of our study was to evaluate preliminary results in a small group of oral cancer patients treated by HDR BT. Seventeen applications were performed on 16 patients in years 2001-2004, in 15 cases for new tumor (mobile tongue 10x, floor of mouth 2x, lip 3x) and in 2 cases for local recurrence after radiotherapy. Ten treatments (for T1-2N0 tumors and recurrences) were performed with brachytherapy alone (18 x 3 Gy twice daily), seven patients (T2-3 N0-2 tumors) were treated with a combination of external beam radiotherapy (40-68 Gy) and brachytherapy (2-6 x 3 Gy twice daily). The plastic tubes technique was used for brachytherapy. Follow-up periods were between 8-46 months (median 17). Fifteen patients were disease free during follow-up period. One patient (brachytherapy alone for T2N0M0 mobile tongue cancer) died immediately after neck dissection for the neck recurrence due to the heart failure. The other one died due to distant metastases but without local recurrence. Acute complications were mucositis gr. II at maximum, late complications were ulcer of soft tissues in 3 and superficial bone necrosis in 2 cases. The evaluation of the brachytherapy implants was done according ICRU 58 recommendations. Hyperfractionated high dose rate brachytherapy alone or as a boost to external beam radiotherapy is feasible with promising local control. Carefull planning of the implant and mandibular shielding are necessary to avoid complications.     

Prognostic role of angiogenesis and its correlations with thymidine phosphorylase and p53 expression in ductal adenocarcinoma of the pancreas

BACKGROUND/AIMS: Currently, little information is available regarding the prognostic role of angiogenesis and its correlation with Thymidine phosphorylase (dThdPase) in ductal adenocarcinoma of the pancreas. In the present study, we aimed to evaluate whether tumor angiogenesis, dThdPase expression correlates with prognosis in patients after radical surgical treatment for ductal adenocarcinoma of the pancreas and to investigate the correlation between tumor angiogenesis and dThdPase expression. Furthermore, the role of p53 expression in tumor neovascularization was also examined in this study. METHODOLOGY: Tissue samples were taken from 32 patients with ductal adenocarcinoma of the pancreas after radical surgical treatment. Intratumoral microvessel density (IMVD) and dThdPase, p53 expression were examined immunohistochemically. RESULTS: Increased IMVD significantly correlated with the tumor size, lymph node metastasis and advanced TNM stage (p < 0.05, respectively). Furthermore, increased IMVD correlated withpoorer survival curve (p < 0.05). A significant correlation was present between IMVD and dThdPase expression (p < 0.001), while dThdPase expression did not correlate with prognosis. p53 expression correlated with prognosis, whereas no significant correlation was shown between p53 expression and IMVD in ductal adenocarcinoma of the pancreas. CONCLUSIONS: Tumor angiogenesis is associated with clinicopathological factors regarding tumor progression and may be an important prognostic factor in ductal adenocarcinoma of the pancreas. dThdPase plays an important role in tumor angiogenesis in ductal adenocarcinoma of the pancreas. Mutant p53 expression may not involve in tumor angiogenesis in ductal adenocarcinoma of the pancreas.     

A case of primary lung cancer in a young female with tongue cancer]

We describe a case of lung tumor in a 33-year-old woman with tongue cancer. She had noticed a painful sensation in her tongue in April 2000. The results of a physical examination showed a 22 x 11 mm ulcerated lesion on the right side of her tongue. A biopsy specimen showed a moderately differentiated squamous cell carcinoma. A preoperative chest radiograph showed no evidence of pulmonary metastasis. No neck lymphadenopathy was found. The tongue cancer was resected in September 2000, and the pathological stage was T2 N0 M0. A solitary pulmonary lesion appeared 8 months after the surgery. A Histological examination of a transbronchial lung biopsy specimen showed a moderately differentiated squamous cell carcinoma. It was difficult to distinguish histopathologically or immunohistochemically between a second primary tumor and a metastasis, but the pulmonary lesion was considered to be a second primary tumor on the basis of a single endobronchial lesion that appeared after the T2 tongue cancer with no regional recurrence or cervical lymphadenopathy. Treatment with chemotherapy and irradiation was not effective and the patient died 3 months after the diagnosis of lung cancer.     

Prognostic angiogenic markers(endoglin,VEGF, CD31) and tumor cell proliferation(Ki67) for gastrointestinal stromal tumors

AIM: To evaluate the correlation between the immunoexpression of angiogenic markers [CD31, CD105 and vascular endothelial growth factor(VEGF)], proliferative index(Ki67), and prognosis of patients with gastrointestinal stromal tumors(GIST).METHODS: This is a retrospective study of 54 GIST cases. Medical records were searched to obtain the GIST patients' demographic and clinical data, and paraffin-embedded blocks of tumor samples were retrieved from the hospital archives to conduct a new immunohistochemical evaluation. The tumor samples of GIST patients were subject to immunohistochemical evaluation for endoglin(CD105), CD31, VEGF, and Ki67 expression. The CD105 and CD31 intratumoral microvascular density(IMVD) was measured using automated analysis. We determined the correlation between the immunoexpression of CD105, CD31, VEGF,Ki67 and prognosis. In addition, we conducted a cutoff analysis using the receiver-operating characteristic curve. VEGF positivity was classified as either null/weak or strong. Ki67 was evaluated using a cutoff of 5%positive cells. The prognosis was classified as good(patient alive without recurrence) or poor(patient with recurrence/death).RESULTS: The distribution of tumor sites among the54 analyzed samples was as follows: 27(50%) in the stomach, 20(37.1%) in the small intestine, 6(11.1%)in the colon, and 1(1.8%) in the esophagus. The size of the tumors ranged from 2 to 33 cm(median: 8cm); in 12 cases(22.2%), the tumor was below 5 cm at the largest diameter, but in 42 cases(77.7%), the tumor was larger than 5 cm. The means of CD105 and CD31 were significantly higher in the group with poor prognosis(P 0.001). The cut-off values of CD105(1.2%) and CD31( 2.5%) in the receiver-operating characteristic curve were related to a poorer prognosis.Cases with a better prognosis showed significantly null/weak staining for VEGF(P 0.001). Ki-67 expression of≥ 5% was strongly correlated with a worse prognosis(P 0.001). In the multivariate analysis, CD105 was the variable that most strongly correlated with prognosis.CONCLUSION: The IMVD cutoff values for the angiogenic markers CD105 and CD31, may be prognostic factors for GIST, in addition to VEGF and Ki67.     

Clinicopathological and prognostic implications of endoglin （CD105） expression in hepatocellular carcinoma and its adjacent non-tumorous liver

AIM: The expression pattern of endoglin (CD105) in hepatocellular carcinoma (HCC) has not been reported so far. We hypothesized that CD105 could differentially highlight a subset of microvessels in HCC, and intratumoral microvessel density (IMVD) by CD105 immunostaining (IMVD-CD105) could provide better prognostic information than IMVD by CD34 immunostaining (IMVD-CD34). METHODS: Paraffin blocks of tumor and adjacent non-tumorous liver tissues from 86 patients who underwent curative resection of HCC were used for this study. Serial sections were stained for CD105 and CD34, respectively, to highlight the microvessels. IMVD was counted according to a standard protocol. RESULTS: In the HCC tissues, CD105 was either negatively or positively stained only in a subset of microvessels. In contrast, CD34 showed positive and more extensive microvessel staining in all cases examined. However, in the adjacent non-tumorous liver sections, CD105 showed a diffuse pattern of microvessel staining in 20 of 86 cases, while CD34 showed negative or only focal staining of the sinusoids around portal area. Correlation with clinicopathological data demonstrated that lower scores of IMVD-CD105 were found in larger sized tumors [mean 41.4/0.74 mm2 (>5 cm tumor) vs 65.9/0.74 mm2 (≤5 cm tumor), P= 0.043] and more aggressive tumors, as indicated by venous infiltration [36.8/0.74 mm2 (present) vs 64.2/0.74 mm2 (absent), P = 0.020], microsatellite nodules [35.1/0.74 mm2 (present) vs 65.9/0.74 mm2 (absent), P= 0.012], and advanced TNM tumor stage [38.8/0.74 mm2 (stage 3 or 4) vs 68.3/0.74 mm2 (stage 1 or 2), P= 0.014]. No prognostic significance was observed when median values were used as cut-off points using either IMVD-CD105 or IMVD-CD34. However, the presence of the diffuse pattern of CD105 expression in the adjacent non-tumorous liver tissues predicted a poorer disease-free survival (median 8.6 vs 21.5 mo, P= 0.026). CONCLUSION: Our data demonstrate that a lower IMVD-CD105 is associated with larger and more aggressive tumors. In this study, IMVD-CD105 did not provide significant prognostic information. However, active angiogenesis as highlighted by diffuse CD105 staining of the microvessels in the adjacent non-tumorous liver tissues is predictive of early recurrence.     

Surgical management of patients with bowel obstructions secondary to gastric cancer

AIM: To assess whole-body fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the management of small bowel obstructions (SBOs) secondary to gastric cancer and its role in treatment strategies. METHODS: The medical records of all of the patients who were admitted for an intestinal obstruction after curative resection for gastric cancer were retrospectively reviewed. PET/CT was performed before a clinical treatment strategy was established for each patient. The patients were divided into 2 groups: patients with no evidence of a tumor recurrence and patients with evidence of a tumor recurrence. Tumor recurrences included a local recurrence, peritoneal carcinomatosis or distant metastases. The primary endpoint was the 1-year survival rate, and other variables included patient demographics, the length of hospital stay, complications, and mortality. RESULTS: The median time between a diagnosis of gastric cancer and the detection of a SBO was 1.4 years. Overall, 31 of 65 patients (47.7%) had evidence of a tumor recurrence on the PET/CT scan, which was the only factor that was associated with poor survival. Open and close surgery was the main type of surgical procedure reported for the patients with tumor recurrences. R0 resections were performed in 2 patients, including 1 who underwent combined adjacent organ resection. In the group with no evidence of a tumor recurrence on PET/CT, bowel resections were performed in 7 patients, adhesiolysis was performed in 7 patients, and a bypass was performed in 1 patient. The 1-year survival curves according to PET/CT evidence of a tumor recurrence vs no PET/CT evidence of a tumor recurrence were significantly different, and the 1-year survival rates were 8.8% vs 93.5%, respectively. There were no significant differences (P = 0.71) in the 1-year survival rates based on surgical vs nonsurgical management (0% with nonoperative treatment vs 20% after exploratory laparotomy). CONCLUSION: 18 F-FDG PET/CT can be used to identify the causes of bowel obst     

Factors influencing outcome of surgery for stage I rectal cancer

Stage I rectal cancer (T1N0M0, T2N0M0) carries excellent prognosis with up to 90% of long term survival rates and complete cure can be expected with curative surgery. However 10 to 15% of these patients show local recurrence and mortality seen in five years. The aim of this study is to analyze the prognostic factors that influence the overall and disease free survival in patients with stage I rectal cancer. Eighty-five patients with stage I (T1N0M0, T2N0M0) rectal cancer that had potentially curative surgery were entered into the study. The patients were evaluated according to age, sex, preoperative carcinoembryonic antigen (CEA) level, type of surgical procedure, tumor distance from anal verge, tumor size, depth of invasion, histological differentiation, presence of tumor ulceration, peritumoral vascular invasion, peritumoral lymphatic invasion and peritumoral perineural invasion. Five year overall and disease free survival rates for the patients were 88% and 74%, respectively. Multivariate analysis showed that independent predictors of recurrence were differentiation and peritumoral vascular invasion, and independent predictor of overall survival was only differentiation. Stage I rectal cancer patients with poor differentiation and peritumoral vascular invasion are at high risk for recurrence and should be evaluated for adjuvant therapies.     

Role of Serum Tumor Markers in Monitoring for Recurrence of Gastric Cancer Following Radical Gastrectomy

It has been suggested that the serum tumor markers AFP, CEA, and CA19-9 may serve as prognostic factors or indicators for recurrence after radical gastrectomy for gastric cancer. We compared the value of these markers in a group with (n=52) and a group without recurrent gastric cancer (n=52) according to the site of recurrence. Serum levels of tumor markers were measured at the time of preoperative diagnosis and at follow-up. At least one tumor marker was positive preoperatively in 20 with recurrence vs. 7 controls (p=0.007). The peritoneum was the most common recurrent site. The positive predictive value of AFP was high at the time of diagnosis and CA19-9 positivity was high at the time of recurrence. Positive CEA suggested recurrence to the liver. In summary, an elevated tumor marker at diagnosis or during follow up may identify patients at higher risk for a recurrence. CA19-9 may be especially useful as a marker for peritoneal recurrence of the gastric cancer, and CEA for recurrence to liver.This paper was supported by the Dong-A University Research Fund in 2005     

Treatment of locoregional recurrence after intentional curative resection of pancreatic cancer.

In order to analyze the results of treatment of patients with locoregional recurrence after intentional curative resection of pancreatic cancer, a retrospective study was performed. During the period 1978-1988, 108 patients underwent an intentional curative resection fo the pancreas. In 34 patients locoregional recurrence occurred, all within a period of three years (cumulative recurrence rate 56%). Sixty-eight percent of the patients presented with upper abdominal pain, and 62% with weight loss. Survival was significantly better (p = 0.02) in the group of 18 patients without distant metastases (1-year survival 22%) than in the 16 patients with distant metastases (1-year survival 0%). Five patients without proven distant metastases were treated by resection or chemotherapy. The mean survival was 33 months (range 6-74) in the treated group, and 4 months (0.4-7 months) in the untreated group, p = 0.002. In this retrospective study the longest survival was seen after radical resection of locoregional tumor recurrence. We therefore recommend that patients with locoregional recurrence without distant metastases after intentional curative resection of pancreatic cancer be treated.     

Microvessel organization and structure in experimental brain tumors: microvessel populations with distinctive structural and functional properties.

We studied microvessel organization in five brain tumor models (ENU, MSV, RG-2, S635cl15, and D-54MG) and normal brain, including microvessel diameter (LMVD), intermicrovessel distance (IMVD), microvessel density (MVD), surface area (S(v)), and orientation. LMVD and IMVD were larger and MVD was lower in tumors than normal brain. S(v) in tumors overlapped normal brain values and orientation was random in both tumors and brain. ENU and RG-2 tumors and brain were studied by electron microscopy. Tumor microvessel wall was thicker than that of brain. ENU and normal brain microvessels were continuous and nonfenestrated. RG-2 microvessels contained fenestrations and endothelial gaps; the latter had a maximum major axis of 3.0 microm. Based on anatomic measurements, the pore area of RG-2 tumors was estimated at 7.4 x 10(-6) cm(2) g(-1) from fenestrations and 3.5 x 10(-5) cm(2) g(-1) from endothelial gaps. Increased permeability of RG-2 microvessels to macromolecules is most likely attributable to endothelial gaps. Three microvessel populations may occur in brain tumors: (1) continuous nonfenestrated, (2) continuous fenestrated, and (3) discontinuous (with or without fenestrations). The first group may be unique to brain tumors; the latter two are similar to microvessels found in systemic tumors. Since structure-function properties of brain tumor microvessels will affect drug delivery, studies of microvessel function should be incorporated into clinical trials of brain tumor therapy, especially those using macromolecules.