Endoscopic closure of experimental iatrogenic gastric fundus perforation using over-the-scope clips in a surviving canine model.

BACKGROUND AND AIM: To evaluate the effectiveness and outcomes of endoscopic closure of a gastric fundus perforation using over-the-scope clips (OTSCs) system in a surviving canine model. METHODS: Gastric fundus perforations (20-mm diameter) were created by an endoscopic needle-knife in six dogs. The perforations then were closed by the OTSC system. Gastroscopy was performed to evaluate the postoperative perforation healing every week. The animals were sacrificed 4 weeks later to examine the possible intraperitoneal complications, and the healing of the perforation was examined histopathologically. RESULTS: The gastric fundus perforations could primarily be closed using one OTSC in each experimental dog, and the mean time of the procedure was 17.3 ± 7.6 min (9-26 min). All animals survived without postoperative complications. The OTSC retention was observed in one dog at the end of 4 weeks, and the apparent foreign-body reaction was examined pathologically. CONCLUSIONS: Our surviving animal study demonstrated that the OTSC clip system could reliably close gastric fundus perforations without complications.

[Surgical treatment and prognostic analyses of bronchopulmonary carcinoid tumors].

OBJECTIVE: To explore the surgical treatment and prognostic factors of bronchopulmonary carcinoid tumors (BPC). METHODS: The clinical data of 65 patients undergoing surgery for BPC from May 1999 to December 2007 were reviewed retrospectively. The predictors of univariate and multivariate analyses included gender, age, smoking history, pathological type and tumor stage. RESULTS: The procedures included segmentectomy (n = 1), lobectomy (n = 36), bilobectomy (n = 6), sleeve resection (n = 4), pneumonectomy (n = 11), carinal resection (n = 2), bronchoplastic resection (n = 4) and exploratory thoracotomy (n = 1). The 1- , 3- and 5-year overall survival rates were 86.2%, 73.8% and 64.6% respectively. Univariate analysis showed that gender (P = 0.029), age (P = 0.003), smoking history (P = 0.039), pathological type (P < 0.01), tumor stage (P < 0.01), postoperative radiochemotherapy (P < 0.01), lymph node metastasis (P < 0.01) and surgical type (P = 0.042) were prognostic factors. And multivariate analysis revealed that pathological type (P = 0.019) and lymph node metastasis (P < 0.01) were independent prognostic factors. CONCLUSION: Surgery remains a first-choice for BPC. The major resection procedure is anatomical lobectomy or pneumonectomy. Both pathological type and lymph node metastasis are independent prognostic factors.

Mouse models of epithelial ovarian cancer for preclinical studies.

Epithelial ovarian cancer (EOC) is the leading cause of gynecological cancer-related mortality in the developed world. EOC is a heterogeneous disease represented by several histological and molecular subtypes. Therefore, exploration of relevant preclinical animal models that consider the heterogenic nature of EOC is of great importance for the development of novel therapeutic strategies that can be translated clinically to combat this devastating disease. In this review, we discuss recent progress in the development of preclinical mouse models for EOC study as well as their advantages and limitations.

[Surgical treatment of bilateral thoracotomy in patients with lesions of left main bronchus invading carina].

OBJECTIVE: To investigate the outcome for surgical treatment of bilateral thoracotomy in patients with lesions of left main bronchus invading carina by bilateral thoracotomy. METHODS: The clinical data of 4 patients with lesions of left main bronchus invading carina undergoing bilateral thoracotomy were retrospectively reviewed. RESULTS: There were two male and two female patients with a median age of 37.5 (range: 27 - 55) years old. Four patients were all accessed by bilateral thoracotomy, and received carinal reconstruction. Of these 4 patients, three patients received left pneumonectomy and one patient received carinal resection without concomitant pulmonary resection. Pathological results showed that one patient had tuberculosis. And other three patients were of 1 squamous cell carcinoma and 2 adenoid cystic carcinomas. Three patients received mechanical ventilation for a period of 3 - 21 days. one patient died of anastomotic dehiscence at 5 days postoperatively. CONCLUSION: Bilateral thoracotomy is an alternative approach for relatively young patients with decent cardiopulmonary functions with lesions of left main bronchus invading carina. Operation type should be based on histopathological type and length of involved left main bronchus.

[Surgical results of T4 lung cancer invading left atrium and great vessels].

OBJECTIVE: To analyzed the indication and prognostic factors of surgical treatment of lung cancer invading left atrium and great vessels (T4). METHODS: We retrospectively reviewed the database of 136 T4 lung cancer (tumors invading left atrium and great vessels) patients who received surgical treatment in Cancer Hospital of Chinese Academy of Medical Science (CAMS) from September 1981 to January 2007. There are 114 men and 22 women, the median age was 58 years (range 28 - 76). All patients were divided into three subgroups according to the invading site: tumor invading left atrium group, tumor invading superior vena cava group and tumor invading pulmonary artery group. All patients were divided into two subgroups according to the character of operation: complete resection group and incomplete resection group. Patients were divided into three subgroups according to pathological lymph node status: N0, N1 and N2 group. RESULTS: One hundred and thirty six lung cancer patients received resection of primary lesions plus arterioplasty of pulmonary artery (PA) (n = 83) and/or angioplasty of superior vena cava (SVC) (n = 21) and/or partial resection of left atrium (LA) (n = 32). Complete resection was possible in 120 patients and 16 patients underwent incomplete resection. Five-year survival was 43.0% for entire group, 52. 8% for PA group, 18.2% for SVC group and 18.4% for LA group. Factors significantly influencing the overall 5-year survival were the pathologic N status (5-year survival 15.1% for N2, 5-year survival 44.9% for N1, 5-year survival 74% for N0 group; N2 versus N1 versus N0, P = 0.028) and the completeness of resection (5-year survival 37.5% for complete resection, 5-year survival 22.4% for incomplete resection group; complete versus incomplete, P = 0.042). Pathological lymph node status but not histology and character of operation was an independent prognostic factor using Cox regression analysis (P = 0.01, RR = 1.923, 95% CI: 1.172 -3. 157). CONCLUSION: Pathological lymph node status is an independent prognostic factor for T4 lung cancer. Patients with pathological N0-1 lung cancer invading left atrium and great vessels (T4) may benefit from surgical treatment. In the preoperative workup, every possible effort should be made to achieve a careful evaluation of mediastinal lymph noda status. Compared with incomplete resection group, complete resection group may have a better prognosis. Tumor invading extrapericardial PA may be defined as T2.

[Mechanisms of human telomerase reverse transcriptase RNAi which increases hepatocellular carcinoma cell apoptosis induced by TRAIL].

OBJECTIVES: To investigate the mechanisms for human telomerase reverse transcriptase (hTERT) RNA interference (RNAi) in increasing hepatocellular carcinoma cell apoptosis induced by TNF-related apoptosis-inducing ligand (TRAIL). METHODS: Cell apoptosis was identified by flow cytometry analysis after annexin V/PI double staining. Expression of apoptosis-related proteins, procaspase-8, -9, -3, Bax, Bcl-2 and hTERT, were identified by Western blotting analysis; telomerase activity and telomere length were detected by telomeric repeat amplification protocol (TRAP) and telomere amount and length assay (TALA) methods. RESULTS: Hepatocellular carcinoma cell apoptosis induced by TRAIL were all significantly increased by hTERT RNAi (P less than 0.05). For example, apoptosis rates were enhanced from 5.53% (untransformed) to 10.35% (transformed) in HepG 2 cells and from 14.73% to 77.24% in SMMC 7721 cells after being treated by 100 ng/ml TRAIL for 24 h. Moreover, activation of procaspase-8, -9 and -3 in transformed cells after being treated by TRAIL were all significantly raised (P less than 0.05) in a dose-dependent manner. The expression of procaspase-8, -9 and Bcl-2 were effectively augmented (P less than 0.05), but expressions of Bax and hTERT were strikingly decreased (P less than 0.05). Meanwhile, telomerase activity was apparently suppressed and telomere length was markedly shortened (P less than 0.05). There were no remarkable differences in these effects between control cells and the untransformed cells (P more than 0.05). CONCLUSION: Enhanced cell apoptosis induced by TRAIL through hTERT RNAi may be related to up-regulation of procaspase-8 and -9 expressions. However the down-regulation of hTERT expression, reduced telomerase activity and shortened telomere length may not be related to expressions of Bcl-2 and Bax.

Alcoholization of pyogenichepatic abscess with absolute alcohol in Bama minipigs.

Pyogenic hepatic abscess (PHA) is a rare, but potentially serious disease. At present, ultrasound-guided or computed tomography-guided percutaneous needle aspiration or catheter drainage is appropriate as a first-line treatment. However, it is difficult to aspirate or drain pus and to select the appropriate antibiotic therapy if the abscess consists of thick pus and polymicrobial confections, or its pathogenic bacterium is multidrug resistant and cryptogenic. Case studies of alcoholization provide a novel method to manage PHA. However, the efficacy and safety of this treatment should be further evaluated. In the present study, the therapeutic efficacy and complications of alcoholization for PHAs in Bama minipigs were investigated. PHAs were prospectively treated by ultrasound-guided percutaneous instillation of absolute alcohol in the abscess cavity. The criteria for considering a successful intervention were met in all minipigs subsequent to alcoholization twice within 14 days. The procedures were well tolerated in all animals, and there were no alcoholic adverse effects or procedure-associated complications. In conclusion, ultrasound-guided percutaneous alcoholization is a safe and effective procedure to manage PHA. The problems of thick pus aspiration and selection of an appropriate antibiotic observed in other treatments were resolved effectively using alcoholization. This technique may reduce the treatment period and possibly become a novel strategy for the management of PHA.

[Effects of hTERT RNAi on apoptosis of hepatocellular carcinoma cells induced by TRAIL].

OBJECTIVE: To study the effects of human telomerase reverse transcriptase (hTERT) RNA interference (RNAi) on biological characteristics of hepatocellular carcinoma cell lines HepG2 and SMMC-7721 and on apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). METHODS: Small hairpin hTERT (shTERT) sequence was identified by PCR method; hTERT expressions, morphological features, cell proliferation and replicative senescence were respectively determined using RT-PCR, hematoxylin-eosin (HE) staining, growth curve and beta-galactosidase (b-Gal) staining; cell cycle and apoptosis were identified using flow cytometry after propidium iodide (PI) staining and annexin V/PI double staining. RESULTS: shRNA were found in 6/8 HepG2 and 6/6 SMMC-7721 cell clones transformed by the recombined plasmid pSilencer 3.1-H1 neo-shTERT. The interference rates of hTERT on HepG2 and SMMC-7721 were 100% and 43.3% respectively. Cells in G2-M phases increased from 7.1% to 10.6% and from 6.9% to 7.9% respectively; and the percentage of replicative senenscence cells increased from 0 to 20.4% and from 3.6% to 10.0% respectively. The nucleus/cytoplasm ratios of the cells were obviously decreased after hTERT RNAi treatment. Moreover, apoptosis of hepatocellular carcinoma cells and apoptosis induced by TRAIL were strikingly increased by hTERT RNAi (P < 0.05). For example, apoptosis rates were increased from 3.5% to 5.2% in HepG2 cells and from 4.8% to 7.9% in SMMC-7721 cells after hTERT RNAi treatment. Apoptosis rates were increased from 5.3% to 10.4% in HepG 2 cells and from 13.9% to 77.2% in SMMC-7721 cells after being treated by 100 ng/ml TRAIL for 24 h. However, there were no remarkable changes between control cells and untransformed cells. CONCLUSION: hTERT RNAi not only has a significant effect on biological characteristics of hepatocellular carcinoma cells, but also obviously can increase cell apoptosis induced by TRAIL.

[Postoperative respiratory failure in patients with cancer of esophagus and gastric cardia].

OBJECTIVE: We retrospectively analyzed the cause and death risk of 114 postoperative respiratory failure patients found in 3519 patients with esophageal cancer and 1495 patients with carcinoma of gastric cardia surgically treated between January 1992 and May 2003. METHODS: To analyze the reasons causing postoperative respiratory failure in surgically treated esophageal or gastric cardia cancer patients, and the correlation between the death risk of postoperative respiratory failure and preoperative pulmonary function tests, postoperative complications, operation modes, history of preoperative accompanying diseases and so on using Binary Logistic Regression analysis and Chi-square tests (chi(2)) in SSPS statistics software. RESULTS: In this series, postoperative respiratory failure developed in 97 of 3519 (2.76%) esophageal cancer patients and 17 of 1495 (1.14%) gastric cardia cancer patients, which were mainly caused by severe respiratory tract infection (37.7%, 43/114) and operative complications (35.1%, 40/114) such as: anastomotic leakage or perforation of thoracic stomach, extensive bleeding during operation, chylothorax, etc, totally accounting for 72.8% (83/114). In contrast with lung cancer patients, most of the postoperative respiratory failure (69.3%) occurred in the patients who had perioperative complications but almost always normal preoperative pulmonary function tests. Other reasons to cause postoperative respiratory failure were: extubation in unconscious patients at the end of general anesthesia; over-infusion during operation; pulmonary artery embolism; severe arrhythmia and so on. All patients except 2 were treated in ICU by mechanic ventilation through intubation and/or tracheotomy. Eighty patients (70.2%) were intubated and/or had tracheotomy within 3 days postoperatively. Seventy patients (61.4%) were rescued successfully, whereas 44 cases (38.6%) died of postoperative respiratory failure and/or other postoperative complications. Univariate analysis and multivariate analysis by binary logistic regression indicated that: severe perioperative complications, more postoperative complications, poor preoperative pulmonary function, radical preoperative radiotherapy, intubation and/or tracheotomy after the second postoperative day and long period of mechanic ventilation were the major risk factors leading to death once the postoperative respiratory failure developed. The former 3 factors were independent risk factors leading to death with OR of 2.50, 2.37, 1.68, respectively. Age, sex, operation modes, history of preoperative accompanying disease, prophylactic antibiotics were not demonstrated as statistically significant risk factors correlated with death. CONCLUSION: Severe perioperative complications and respiratory tract infection are the two major causes of postoperative respiratory failure in patients with cancer of esophagus and gastric cardia. Patients with severe perioperative complications or poor preoperative pulmonary function or association with more than two kinds of postoperative complications have much higher death risk than other patients when they develop postoperative respiratory failure. Careful manipulation during operation and effective perioperative management are the most important measures to avoid postoperative respiratory failure and high mortality.

[Diagnosis and surgical treatment for stage I non-small-cell lung cancer].

OBJECTIVE: To evaluate the results of surgery and the diagnosis of stage I non-small-cell lung cancer (NSCLC). METHODS: The survival of 274 stage I NSCLC patients who underwent surgery from 1991 to 1998 were statistically analyzed by the Kaplan-Meier method. Comparison of the differences in survival rates among groups were made according to the Logrank test. The follow-up time was at least 5 years with a follow-up rate of 97.8%. RESULTS: The overall 1-, 3-, 5-year survival rates for patients with pathologic stage I lesion were 92.9%, 79.6% and 66.1%. The 5-year survival rates for patients with squamous-cell carcinoma, adenocarcinoma, adenosquamous and alveolar-cell carcinoma were 73.3%, 55.3%, 52.2%, 71.7%, respectively. The 1-, 3-, 5-year survival rates for T1N0 were 95.0%, 83.2%, 74.3% whereas those of T2N0 lung lesions were 90.8%, 75.9%, 59.9% (P < 0.05). The 1-, 3-, 5-year survival rates of regular lobectomy were 94.1%, 79.3%, 67.5% and of conservative resection (segmentectomy and wedge resection) were 76.5%, 50.0%, 38.3% (P < 0.05). There was no perioperative mortality. The postoperative complications were: intrathoracic hemorrhage (2 patients, successfully treated by second thoracotomy) and chylothorax (1 patient, healed after conservative treatment). CONCLUSION: The 5-year survival rate of pathologic stage I non-small-cell lung cancer is 66.1%. The outcome of patients with squamous-cell carcinoma (73.3%) is similar to that of alveolar-cell carcinoma (71.7%) which, however, is better than that of adenocarcinoma (55.3%) or adenosquamouscarcinoma (52.5%). The overwhelming superiority in result of IA (T1N0) lesion (74.3%) over the IB (T2N0) disease (59.9%) is quite impressive. Regular lobectomy plus radical mediastinal lymph node dissection is the appropriate management for stage I non-small-cell lung cancer.

Effects of cisplatin on telomerase activity and telomere length in BEL-7404 human hepatoma cells.

Telomerase activity was inhibited in a dose and time-dependent manner with the treatment of cisplatin for 24, 48, or 72 h in a concentration ranged from 0.8 to 50 microM in BEL-7404 human hepatoma cells. There were no changes in expression pattern of three telomerase subunits, its catalytic reverse transcriptase subunit (hTERT), its RNA component (hTR) or the associated protein subunit (TP1), after cisplatin treated for 72 h with indicated concentrations. Mean telomere lengths were decreased by the cisplatin treatment. Cell growth inhibition and cell cycle accumulation in G2/M phase were found to be correlated with telomerase inhibition in the present study, but percentages of cell apoptosis did not change markedly during the process.

Value of radiotherapy after radical surgery for esophageal carcinoma: a report of 495 patients.

BACKGROUND: Despite three decades of debate, no conclusion has been reached concerning the effectiveness of postoperative radiotherapy for resected esophageal carcinoma. From 1986 through 1997, a prospective randomized study was carried out with 495 patients in an attempt to define the value of this therapeutic modality. METHODS: A total of 495 patients with esophageal cancer who had undergone radical resection were randomized by the envelope method into a surgery-alone group (S) of 275 patients and a surgery plus radiotherapy group (S + R) of 220 patients. Radiation treatment was started 3 to 4 weeks after the operation. The portals encompassed the entire mediastinum and bilateral supraclavicular areas. A midplane dose of 50 to 60 Gy in 25 to 30 fractions was delivered over 5 to 6 weeks. RESULTS: The overall 5-year survival rate was 31.7% for the S group and 41.3% (p = 0.4474) for the S + R group. The 5-year survival rates of patients who were lymph node positive were 14.7% and 29.2% (p = 0.0698), respectively. Five-year survival rates of stage III patients were 13.1% and 35.1% (p = 0.0027), respectively. CONCLUSIONS: Postoperative prophylactic radiotherapy improved the 5-year survival rate in esophageal cancer patients with positive lymph node metastases and in patients with stage III disease compared with similar patients who did not receive radiation therapy. These results were almost significant for patients with positive lymph node metastases and highly significant for patients with stage III disease.

Telomerase inhibition and telomere loss in BEL-7404 human hepatoma cells treated with doxorubicin.

AIM: To study the effects of doxorubicin on telomerase activity and telomere length in hepatocellular carcinoma. METHODS: Telomerase activity was assayed with a non-radioisotopic quantitative telomerase repeat amplification protocol-based method. The effect of doxorubicin (DOX) on the growth of BEL-7404 human hepatoma cells was determined by microculture tetrazolium assay. Mean telomere length (terminal restriction fragment) was detected by Southern blot method. The expression of telomerase subunits genes was investigated by RT-PCR. Cell apoptosis and cell cycle distribution were evaluated by flow cytometry. RESULTS: Telomerase activity was inhibited in a dose and time-dependent manner in BEL-7404 human hepatoma cells treated with DOX for 24, 48 or 72 h in concentrations from 0.156 to 2.5 microM which was correlated with the inhibition of cell growth. No changes were found in the mRNA expression of three telomerase subunits (hTERT, hTR and TP1) after drug exposure for 72 h with indicated concentrations. The cells treated with DOX showed shortened mean telomere length and accumulated at the G(2)/M phase. However, there was almost no effects on cell apoptosis by DOX. CONCLUSION: The telomerase inhibition and the telomere shortening by DOX may contribute to its efficiency in the treatment in hepatocellular carcinoma.

[Clinicopathological features and prognosis of thymic carcinoma].

OBJECTIVE: To investigate the clinicopathologic features of thymic carcinoma and assess its prognostic factors. METHODS: A retrospective analysis was performed in 54 patients with thymic carcinoma who underwent surgical resection. Eighteen patients were treated by total resection of the tumor, 17 partial resection and 10 exploratory thoracotomy. The clinical stage was determined according to Masaoka's classification. The survival time and prognostic factors were evaluated by the log-rank and Cox multivariate analysis model. RESULTS: The overall 5-year survival rate was 44.4%. Being located in anterior mediastinum and noncalcification in the tumor pathognomonically played an important role in the differential diagnosis. According to the multivariate analysis, tumor maximum diameter (OR = 1.84), histological subtype (OR = 1.70), completeness of resection (OR = 1.37), tumor invasion of peritumoral organs (OR = 1.32) and postoperative recurrence (OR = 1.26) were significant prognostic factors. Compared with other subtypes, carcinoid tumor had the characteristics of earlier lesion, better resection rate and better prognosis. CONCLUSION: The most important prognostic variables for thymic carcinoma are tumor maximum diameter, histological subtype, completeness of resection, tumoral invasion and postoperative recurrence. Complete resection followed by chemoradiotherapy should be considered as favorable on the basis of a definitive pathologic diagnosis.

[Antisense DNMT1 gene fragment in the sensitivity change of SMMC-7721 cells to tumor necrosis factor related apoptosis inducing ligand and its mechanism].

OBJECTIVE: To observe the sensitivity change of SMMC-7721 cells transfected with antisense DNMT1 gene fragment to tumor necrosis factor related apoptosis inducing ligand (TRAIL) and its mechanism. METHODS: Cell survival rate was measured by trypan blue, apoptosis rate by TUNEL method and the expression of bcl-2, bax and bad by flow cytometry. RESULTS: Cell survival rate of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly lower than that transfected with sense DNMT1 gene fragment or empty vector (P < 0.05 and 0.01), but the apoptosis rate was on the contrary (P < 0.05 or 0.01). The expression of bax and bad (especially the former), but not bcl-2 of SMMC-7721 cells transfected with antisense DNMT1 gene fragment was markedly higher than those of SMMC-7721 cells transfected with sense DNMT1 gene fragment or empty vector. CONCLUSION: The sensitivity of SMMC-7721 cells to TRAIL can be enhanced by the transfection of antisense DNMT1 gene fragment, which may be related to the increase of bax and bad expression.

[Cooperative anti-tumor effect of aspirin and TNF-related apoptosis-inducing ligand].

OBJECTIVE: To observe the anti-tumor effect of combination TNF-related apoptosis-inducing ligand (TRAIL) with aspirin on liver cancer cell line, SMMC-7721. METHODS: The survival fraction of SMMC-7721 cells was measured by MTT assay, apoptosis rate and cell cycle was determined by flow cytometry, and the expression of apoptosis-related gene was identified by western blot. RESULTS: The survival fraction of SMMC-7721 cells treated with 300 ng/ml TRAIL, 3 mmol/L or 10 mmol/L aspirin alone was 82.76%, 81.34% and 71.29% respectively, and the survival fractions of SMMC-7721 cells treated with TRAIL and 3 mmol/L or 10 mmol/L aspirin were 43.54% and 37.8% respectively. The apoptosis rates of SMMC-7721 cells induced by TRAIL and 3 mmol/L or 10 mmol/L aspirin were higher than that induced by TRAIL or aspirin alone (34.76% and 38.56% vs 21.25%, 1.89% and 6.08%), and G0/G1 arrest was observed under TRAIL and aspirin. The expression of Bcl-2 in SMMC-7721 cells treated by 3 mmol/L or 10 mmol/L aspirin decreased markedly, but no effect on Bax. CONCLUSION: The cooperative anti-tumor effect of aspirin and TRAIL may be related to the inhibition of the expression of Bcl-2 by aspirin

[Clinical features of postoperative chylothorax for lung cancer and esophageal cancer].

OBJECTIVE: To define the clinical features of postoperative chylothorax for lung cancer (PCLC), and to compare them with those for esophageal cancer (PCEC). METHOD: We retrospectively analysed clinical characteristics of 12 patients with chylothorax among 4 084 patients receiving resection of lung cancer, as well as 52 in 4 479 patients having resection of esophageal cancer since 1985 at our hospital. RESULTS: The incidence of PCLC was 0.29% and that of PCEC was 1.16%. The percentage of diagnosis confirmed within 4 postoperative days was 33.3% for PCLC, and 76.9% for PCEC. The rate of typical chylous pleural effusion was 83.3% for PCLC, and 5.8% for PCEC. Symptoms and signs of PCLC were much milder than those of PCEC. The re-operation rate was 16.7% for PCLC, and 96.2% for PCEC. All patients were discharged uneventfully. CONCLUSION: The incidence, causes, clinical manifestations, diagnosis, and treatment of PCLC is different from those of PCEC.

[Myasthenia gravis occurring after resection of thymoma].

OBJECTIVE: The aim of this study was to analyses the clinicopathologic features of the patient with myasthenia gravis (MG) occurring after resection of thymoma. METHODS: Data of 15 patients were collected. The follow-up range from 8 to 178 (average 76.7) months. A retrospective analysis was performed through comparison with data of all 112 cases without MG, which had not occurred MG during our average 5.5 years follow-up, operated for thymoma in same period. The statistics analysis adopted chi(2) and t test. RESULTS: (1) According to Masaoka's classification of thymoma, stage I in 7 cases, stage II in 4, stage III in 4. Histologic Bernatz's classification: lymphocyte predominant type in 4, epithelial type in 3, mixed type in 7, unknown in 1. According to Osserman's classification of MG, grade I in 7, IIa in 4, IIb in 3, III in 1. The MG onset times was the postoperative narcotic waking duration-137 (average 33.9) months, and the average remission time was 30.9 (0.5 - 120) months. (2) 4 cases who occur MG as soon as pull up narcotic tube, all adopted nondepolarizing muscular relaxants. (3) MG was discovered in 3 cases (3/67) during postoperative radiotherapy until a average dosage of 36 Gy was received in average 24 days. (4) The tendency of occurring MG following resection was found in female patients with longer duration of disease, mixed type, larger and later stage thymoma as compared with the thymoma group. CONCLUSIONS: The factors including the operation, relatively using overdose relaxation control, choosing unfavorable muscle relaxant and postoperative radiotherapy could induce postoperative MG. An intensive care should be put on the cases with the tendency of occurring postoperative MG.

[Clinical analysis of surgical treatment of primary tracheal tumors].

OBJECTIVE: To summarize the clinical experiences in treating primary tracheal tumors by surgery. METHODS: The clinical data concerning 70 surgically treated patients between 1968 and 2001 were retrospectively analyzed. RESULTS: There were 39 sleeve tracheal resections, 13 carinal resections, 10 lateral tracheal wall resections, 5 local enucleations, and 1 pneumonectomy. The tumors in 2 patients were unresectable. The morbidity rate was 31% (22/70) and operative 30-day mortality for resection with primary reconstruction was 8% (4/52). The tumors were benign in 14 and malignant in 56 cases. The most common malignant tumors were adenoidcystic carcinoma (45%) and squamous cell carcinoma (23%). The cases of benign tracheal tumors were followed up for an average of 5.7 years. After resection for malignant tumors, the overall 5- and 10-year survival rates were 64% (21/33) and 54% (14/26), respectively. CONCLUSIONS: Surgical resection is the most effective treatment of tracheal tumors. Tracheal resection and reconstruction is the treatment of choice for primary tracheal tumors. Benign tumors should be resected conservatively with preservation of tracheal parenchyma. The reduction of operative complications are key points of good surgical results.

Prevalence and pathogenesis of Barrett's esophagus in Luoyang, China.

BACKGROUND: Prevalence of Barrett's esophagus (BE) in Luoyang, China, has not been reported, and its pathogenesis is controversial. The aim of this study was therefore to investigate the prevalence of BE and its underlying factors in the city of Luoyang. METHOD: This was a prospective study in one center. Many patients were analyzed using endoscopy who showed upper gastrointestinal symptoms between August 2006 and June 2007. In addition, the effect of apoptosis-related proteins and heat shock proteins upon BE's pathogenesis were also investigated by an immunohistochemical protocol. RESULTS: Prevalence of BE was at 4.55% and the mean age of those affected was about 10 years older than for esophagitis. Typical reflux symptoms were significantly lower than with esophagitis, whereas signs of caspase-3 and HSP105 elevation were significantly higher. Expression of TERT, HSP70 and HSP90α in BE cases was significantly lower than in esophagitis. However, there was no statistical difference between the two groups in expression of HSP27. CONCLUSIONS: The prevalence of BE is high in Luoyang, which could result from esophagitis despite typical reflux symptoms being relatively uncommon. Initiation and development of BE might be the result of accelerated proliferation, apoptosis and differentiation of original cells to intestinal epithelium.