Search

Considering the features and operating characteristics of special robot, a development of high-power multi-axis control system based on TMSF320F2812 and high current half bridge driver BTS7960 is proposed in this paper. Moreover, the modular design was applied to the driver circuit, current sampling circuit, position detection and CAN bus circuit. The abundant peripherals of TMS320F2812 were fully utilized to improve the stability and reliability of the robot and reduce the volume and power consumption. In the software of robot control system, C language was used to realize the main program and the interrupt program. Through the motor control experiment, the performance of high-power multi-axis control system was tested. The results indicate that the high-power multi-axis control system is reliable and highly integrated, which meets the requirements of the special robot. [ABSTRACT FROM AUTHOR]

Objective: To compare the clinicopathological features and prognosis of esophageal cancer between young and elderly patients., Methods: Clinical data of 716 patients with esophageal squamous cell carcinoma undergoing curative operation from January 1990 to December 1998 at the Cancer Center of Sun Yat-sen University were analyzed retrospectively. Clinicopathological features and prognosis of 117 patients aged ≤45 years (young group) at diagnosis were compared with 599 patients aged >45 years (elderly group)., Results: Except for tumor stage, there were no significant differences of clinicopathology between the young group and the elderly group (all P>0.05). There were more pathologic stage III cancer in the young group than the elderly group (47.9% vs. 33.6%, P=0.010). The 5-year survival rate (36.0% vs 33.8%) and 10-year survival rate (29.2% vs 25.0%) were not significantly different between the two groups (P=0.418). Multivariate analysis showed that the age was not the independent prognostic factors of esophageal squamous cell carcinoma (P=0.160, RR=1.187, 95%CI:0.935-1.506)., Conclusion: Young esophageal cancer patients have more advanced tumors than elderly patients. However, the survival is comparable to the elderly.

Ti-based biomaterial has been widely used as dental and bone implant material although its bioactivity still needs improvement especially for dental implant. The bone morphogenetic proteins(BMPs) bound to Ti-based materials will attract the mesenchymal stem cells to differentiate into osteoblast cells, which benefits the response to the protein-material surface, and finally leads to new bone formation. Several methods including physically mixing, coating, plasma immobilization and cross-linking were used to investigate how BMPs bind to Ti-based biomaterials. The latest research papers are focused on the structure and function of BMPs, and the methods to bind BMPs to Ti-based biomaterial and the evaluation methods after protein immobilization are reviewed in this paper.

Objective: The aim of this study was to evaluate if factors associated with dissected lymph nodes affect the outcome of completely resected stage II (T1-2N1) non-small cell lung cancer (NSCLC)., Methods: Clinical data of 121 patients with complete resection of stage II NSCLC in Sun Yat-sen University Cancer center from January 1998 to December 2004 were reviewed retrospectively and the effect of factors of dissected lymph nodes on overall survival (OS) and disease-free survival (DFS) of NSCLC was analyzed., Results: The univariate analysis demonstrated that the total number of removed lymph nodes, the number of involved N1 lymph nodes, the ratio of involved N1 lymph nodes and the total number of removed N2 lymph nodes were significant prognostic factors for OS. In the multivariate analysis, the total number of removed lymph nodes and the number of involved N1 lymph nodes were independent prognostic factors for OS. In both of univariate and multivariate analyses, tumor size, the total number of removed lymph nodes and the number of involved N1 lymph nodes were independent prognostic factors for DFS., Conclusion: For patients with completely resectable stage II NSCLC, 10 or more lymph nodes should be removed at the surgical resection. Total number of removed lymph nodes >or= 10 is a favorable prognostic factor and involved N1 >or= 3 is an adverse one.

Objective: To evaluate the value of mediastinoscopy in preoperative staging of non-small cell lung cancer (NSCLC) based on survival analysis., Methods: 152 cases of potentially operable NSCLC were enrolled in this study. All cases underwent CT scan and mediastinoscopy for assessment of the mediastinal lymph node status before initial treatment. The definitive treatment was decided on the basis of mediastinoscopy and the survival rate was analyzed with a median follow-up of 30.5 months. Survival analysis was conducted by comparing the lymph node status which was determined by final pathology (groups pN0, pN1, pN2, pN3), CT scan (group cN0-1, cN2-3) and mediastinoscopy (group mN0-1, mN2, mN3)., Results: The 5-year survival rates in group pN0, pN1, pN2 and pN3 were 61.7%, 75.0%, 32.4% and 16.1%, respectively. Both groups pN0 and pN1 had significantly higher survival rates than those in groups pN2 and pN3 (P < 0.05). There were not significant differences between survival rates in groups cN0-1 and cN2-3 (P = 0.670), while the survival rate in group mN0-1 was significantly higher than that in groups mN2 and mN3 (P < 0.05)., Conclusion: Mediastinoscopy is of great value in preoperative staging of NSCLC. Not only does it detect lymph node metastasis more precisely but also better predict the prognosis than CT scan.

Background and Objective: Our previous studies have shown that dendritic cell (DC)-tumor cell fusion vaccine can induce specific antitumor response against esophageal carcinoma cells. This study was to investigate the inhibitory effect of intratumor injection of the antigen-specific cytotoxic T lymphocytes (CTLs) induced by DC-tumor cell fusion vaccine against subcutaneously transplanted esophageal carcinoma cells in nude mice, and to analyze the influence of DC/tumor cell fusion vaccine on proliferation and apoptosis of esophageal carcinoma cells., Methods: Fusion cell vaccine of mature DCs with EC109 cells were generated by the polyethylene glycol (PEG) protocol and the antigen-specific CTLs were induced. The models of transplanted human esophageal carcinoma in nude mouse were established using EC-109 cell line. Thirty-three nude mice with subcutaneous tumors were randomly divided into three groups. Subcutaneous tumors of group A (n=11), group B (n=11) and group C (n=11) were intratumorally injected with the CTLs induced by DC/tumor fusion vaccine, T lymphocytes and RPMI 1,640 medium respectively once a week. After four weeks of intratumor injection, the nude mice were killed and the nodules were anatomized. The mean volume and weight of tumors of each group were measured, and the tumor inhibitory rates of the Group A and the Group B were calculated and compared. The expression of proliferating cell nuclear antigen (PCNA) was detected by immunohistochemistry (S-P method). The mean PCNA-label index (LI) of three groups was compared. The cell cycle and cell apoptosis of the xenograft tumor cells were analyzed by flow cytometry. The mean S-phase fraction (SPF) and the mean rate of cell apoptosis of three groups was compared respectively., Results: Both the mean volume and the mean weight of xenograft tumors in group A (881.45+/-31.14 mm3 and 0.88+/-0.04 g) were significantly smaller than those of group B (1493.37+/-51.67 mm3 and 1.38+/-0.07 g) and group C (2065.77+/-87.55 mm3 and 2.04+/-0.11 g). The tumor inhibitory rates of Group A was significantly higher than that of group B (56.86% vs. 32.35%, F=1218.08, P=0.001). The mean PCNA-LI of xenograft tumors was less in the group A (26.83+/-0.95)% than in the group B (51.82+/-1.51)% and group C (68.93+/-2.40)% (F=1528.39, P=0.000). The mean SPF of xenograft tumors was less in the group A (12.46+/-0.36)% than in the group B (29.39+/-0.96)% and the group C (42.25+/-1.43)% (P<0.05). The mean apoptotic rate of xenograft tumors was less in the group A (38.03+/-1.21)% than in the group B (17.75+/-0.56)% and the group C (6.59+/-0.22)% (P<0.05)., Conclusion: The model of subcutaneous xenograft tumors in nude mice using human esophageal carcinoma cell line EC-109 has been successfully established. CTLs induced by DC/tumor fusion vaccine has specific antitumor immunity efficacy in vivo. CTLs can inhibit the proliferation of tumor cells and induce apoptosis of tumor cells in local tumors.

Objective: To discuss the strategy of mediastinoscopy for the evaluation of mediastinal lymph node status (metastasis or not) of non-small cell lung cancer (NSCLC) prior to surgery., Methods: From October 2000 to June 2007, 152 consecutive NSCLC cases pathologically proven and clinically staged I-III were enrolled in the study. Of the 152 cases, there were 118 males and 34 females. Age ranged 24-79 years old and the median age was 58. All cases underwent CT and mediastinoscopy for the evaluation of mediastinal lymph node status prior to surgery. Compared with the results of final pathology, the positive rate of mediastinoscopy and the prevalence of mediastinal lymph node metastasis were calculated in the NSCLC patients with negative mediastinal or hilar lymph nodes on CT scan (the shortest axis of mediastinal or hilar lymph nodes <1 cm). Clinical characteristics used as predictive factor including sex, age, cancer location, type of pathology, T status, cancer type (central or peripheral), size of mediastinal lymph nodes (the shortest axis <1 cm or >1 cm) on CT scan and serum CEA level were analyzed by univariate and multivariate analysis with Binary logistic regression model to identify risk factors of mediastinal metastasis., Results: The positive rate of mediastinoscopy was 11.6% (8/69) and the prevalence of mediastinal metastasis was 20.1% (14/69) in NSCLC with negative mediastinal or hilar lymph nodes on CT scan respectively. In clinical stage I (cT1-2N0M0) NSCLC the positive rate of mediastinoscopy was 11.3% (7/62), N2 accounting for 6.5% (4/62) and N3 4.8% (3/62), respectively; and the prevalence of mediastinal lymph node metastasis was 19.4% (12/62), N2 ccounting for 14.6% (9/62) and N3 4.8% (3/62), respectively. In the whole group both univariate and multivariate analysis showed that adenocarcinoma or mediastinal lymph nodes > or =1 cm in the shortest axis on CT scan was an independent risk factor to predict mediastinal lymph node metastasis. In NSCLC with negative mediastinal or hilar lymph nodes on CT scan both univariate and multivariate analysis showed that adenocarcinoma was a predictor of mediastinal lymph node metastasis. Conclusion We recommend the policy of routine mediastinoscopy in NSCLC prior to surgery if the mediastinal staging was only based on CT scan. Mediastinal lymph nodes > or =1 cm in the shortest axis on CT scan mandates preoperative mediastinoscopy. Adenocarcinoma also indicates mandatory mediastinoscopy even with negative mediastinal or hilar lymph nodes on CT scan.

Objective: This study was to review the clinical features, diagnosis, treatment, and prognosis of esophageal adenosquamous carcinoma (ASC)., Methods: Clinical data of 22 patients with pathologically confirmed esophageal ASC, treated in the Cancer Center of Sun Yat-sen University from May 1988 to April 2006, were retrospectively analyzed. The survival analysis was performed using Kaplan-Meier method., Results: Of 4208 patients diagnosed as esophageal cancer during the same time in our center, only 22 had esophageal ASC, accounted for 0.52%. The median age of the 22 cases was 60 years (range, 42 to 69 years). Esophageal ASC showed similar clinical symptoms, radiological and endoscopic features to esophageal squamous cell carcinoma (ESCC). Nineteen cases were preoperatively misdiagnosed as ESCC by endoscopic biopsy. Among the 22 patients, 16 were treated by surgery alone, 3 by surgery plus postoperative radiotherapy, and the remaining 3 by radiotherapy, sequential chemoradiotherapy and concurrent chemoradiotherapy, each in one case, respectively. The overall 1-, 3- and 5-year survival rates were 67.6%, 33.8% and 18.1%, respectively, with a median survival time of 24.5 months., Conclusion: Esophageal adenosquamous carcinoma is a rare esophageal disease and prone to be misdiagnosed as esophageal squamous cell carcinoma. Initial surgical treatment combined with other therapies is suggested. The prognosis of esophageal adenosquamous carcinoma has not yet been well established.

Objective: To compare the value of CT and mediastinoscopy in assessment of mediastinal lymph node status in potentially operable non-small cell lung cancer (NSCLC)., Methods: From Oct. 2000 to Jun. 2007, 152 consecutive patients with pathologically proven and stage I to approximately III NSCLC were enrolled into the study. Of the 152 cases, there were 118 males and 34 females, with a median age of 58 years (range, 24 to approximately 79 years). Compared with the final pathology, the sensitivity, specificity, positive and negative predictive values and accuracy of CT and mediastinoscopy for preoperative evaluation of mediastinal lymph node status were calculated, respectively. The accuracy and diagnostic efficacy of CT and mediastinoscopy was compared by Pearson chi(2) test and ROC curve, respectively., Results: The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of detection of mediastinal metastasis was 73.8%, 70.1%, 64.9%, 78.2% and 71.7% by CT, respectively, versus 83.1%, 100.0%, 100.0%, 88.8% and 92.8% by mediastinoscopy, respectively. Both the accuracy and diagnostic efficacy of mediastinoscopy were superior to CT (Pearson chi(2) test, P < 0.001; Z test of the areas under the ROC curve, P < 0.001). The complication rate of mediastinoscopy was 4.6%, and the false negative rate was 7.2%., Conclusion: Mediastinoscopy is safe and effective in preoperative assessment of mediastinal lymph node status in potentially operable NSCLC, while CT alone is inadequate.

Objective: To analyze the prognostic factors of thoracic esophageal squamous cell carcinoma (ESCC) after esophagectomy., Methods: The clinicopathologic data of 716 patients with thoracic ESCC from January 1990 to December 1998 were analyzed retrospectively. There were 538 male and 178 female patients aged from 24 to 78 years old with a median of 57 years old. Cumulative survival rate was analyzed by the Kaplan-Meier method and compared by the Log-rank test. COX regression model was used for multivariate prognostic analysis., Results: The overall 1-, 3-, 5- and 10-year survival rates were 82.9%, 44.3%, 34.2% and 25.7% respectively. The 5-year survival rates was 80.0%, 51.2%, 19.7% and 13.3% for stage I, stage IIA, stage IIB and stage III respectively. Of the 716 patients, 151 (21.1%) patients recurred, including 48 (84.2%) of stage IIA recurrence, 22 (91.7%) of stage IIB recurrence and 63 (90.0%) of stage III recurrence occurred within 3 years postoperatively. Univariate analysis revealed that the factors impacting the prognosis were gender, depth of invasion, lymph node metastasis, pathologic stage, number of lymph node metastatic field, differentiation, surgical margin and tumor relapse. Multivariate analysis showed that depth of invasion, lymph node metastasis, pathologic stage and tumor relapse were independently associated to poor prognosis., Conclusions: Depth of invasion, lymph node metastasis, pathologic stage and tumor relapse are the independent factors of ESCC. Surgery is still the primary treatment for stage I-IIA esophageal cancer; but it is suggested to adopt surgical treatment as primary modality combined with other therapies for stage IIB-III esophageal cancer.

Objective: To investigate the impact of visceral pleural invasion (VPI) on prognosis and staging in patients with stage Ib non-small cell lung cancer (NSCLC)., Methods: Clinical data of 232 patients with stage Ib NSCLC surgically treated by curative resection between January 1994 and December 2003 was retrospectively reviewed. Histopathological diagnosis was reviewed by an experienced pathologist. According to the tumor size and status of VPI, patients were stratified into three group: group A: tumor > 3 cm and VPI(-); group B: tumor < or = 3 cm and VPI (+); group C: tumor > 3 cm and VPI(+). There were 45 patients in group A, 96 in group B and 91 in group C. Kaplan-Meier method was used for survival analysis. Cox proportional hazards model was used for multivariate analysis., Results: 187 (80.6%) patients had visceral plural invasion, while 45 (19.4%) had no. The 5-and 10-year survival rates of patients with VPI were 59.3% and 42.6%, while it was 70.1% and 56.7% for the patients without (P = 0.035), respectively. The 5-year survival rates of patients in group A, B and C were 70.1%, 61.9% and 56.2%; and 10-years survival rates were 56.7%, 50.6% and 35.9%, respectively (P = 0.018). VPI with large size of tumor was revealed by Cox multivariate analysis as an independent prognostic factor (RR = 1.530, 95% CI: 1.132-2.067, P = 0.006)., Conclusion: A significant difference in survival exists among the stage Ib NSCLC patients who have different T status, the patient with > 3 cm tumor and visceral plural invasion may have the worst prognosis. Further studies are still needed to assess whether it is necessary or not to modify the T2 statue of tumor > 3 cm with visceral plural invasion.

Background & Objective: Esophageal cancer is a common malignant tumor in China. At the time of diagnosis, most patients are at locally advanced stage. Up to date, surgical resection is the main treatment of esophageal cancer. This study was to analyze the correlations of clinicopathologic features of stage II thoracic esophageal squamous cell carcinoma (ESCC) to the prognosis., Methods: The clinicopathologic data of 467 patients with stage II thoracic ESCC, treated with surgery from Jan. 1990 to Dec. 1998 in Cancer Center of Sun Yat-sen University, were analyzed. Cumulative survival was analyzed by Kaplan-Meier method and compared by log-rank test. The prognosis was analyzed by Cox regression model., Results: The overall 1-, 3-, 5-, and 10-year survival rates were 87.1%, 54.6%, 43.0%, and 32.3%, respectively. The 5-year survival rates of patients at stage II A and stage II B were 51.0% and 19.9%. Of the 467 cases, 81 (17.3%) recurred, and 70 (86.4%) of them recurred within 3 years after operation. Univariate analysis revealed that the factors affecting the prognosis included gender, depth of invasion, lymph node metastasis, pathologic stage, number of lymph node metastatic fields, differentiation, positive surgical margin and tumor recurrence. Multivariate analysis showed that gender, depth of invasion, pathologic stage, number of lymph node metastatic fields, positive surgical margin and tumor recurrence were independent prognostic factors., Conclusions: Gender, depth of invasion, pathologic stage, number of lymph node metastatic fields, positive surgical margin and tumor recurrence are independent prognostic factors of stage II ESCC. Surgery is still the primary treatment for stage II A esophageal cancer; but surgery-dominant treatment combined with other therapies is recommended for stage II B esophageal cancer.

Objective: To investigate the prognostic effect of mediastinal lymph node dissection in patients with stage I non-small cell lung cancer (NSCLC)., Methods: The clinical data of 330 patients with stage I NSCLC who were treated with curative resection from January 1994 to December 2003 were reviewed retrospectively. According to the extent of mediastinal lymph node dissection and the pathology report, the patients were assigned to lung resection combined with mediastinal lymph node dissection (LND) group or with lymph node sampling (LNS) group. The Kaplan-Meier method was used for survival analysis. COX proportional hazards model was used for multivariate analysis., Results: There were 233 (70.6%) male patients and 97 (29.4%) female patients. The median age was 60 years old. Ninety-eight patients were in stage IA and 233 in stage IB. One hundred and forty patents were in group LND and 190 in group LNS. The mean number of removed lymph nodes in group LND and group LNS were (13.3 +/- 4.7) and (5.2 +/- 3.0) (P < 0.01), respectively. The mean of mediastinal lymph node station sampled in group LND and group LNS were (3.7 +/- 0.9) and (1.3 +/- 1.1) (P < 0.01), respectively. The 5-year and 10-year survival rates of patients in group LND were 72.0% and 66.1%, while in group LNS were 65.9% and 43.0% (P < 0.05), respectively. Other prognostic factors included symptom, staging, visceral pleura invasion and tumor size. LND was disclosed as a favourable prognostic factor at COX multivariate analysis, together with absence of symptom at diagnosis., Conclusion: As compared with LNS, LND can improve survival in stage I NSCLC.

Background & Objective: Multi-disciplinary management for non-small cell lung cancer (NSCLC) has been applied for more than ten years. The progresses in the diagnosis and management of NSCLC might change the factors affecting prognosis. This study was to explore the prognostic factors of NSCLC after complete resection., Methods: Clinical data of 899 NSCLC patients, underwent complete resection from Jan. 1997 to Apr. 2001 at Cancer Center of Sun Yat-sen University, were reviewed. The patients were followed up till 31st Mar. 2006. Survival rates were calculated by Kaplan-Meier method. The prognosis was analyzed by Cox proportional hazards model., Results: The 5-year survival rate of the 899 patients was 43.5% and the median survival time was 48 months. The 5-year survival rates were 81.0% for the patients at stage IA, 60.3% for stage IB, 56.9% for stage IIA, 45.7% for stage IIB, 23.5% for stage IIIA, 20.8% for stage IIIB, and 13.0% for stage IV. Univariate analysis showed that T stage, N stage, M stage, histological type, differentiation, chemotherapy for adenocarcinoma (ADC) at stages II and IV, and mediastinal radiotherapy for ADC at stage N2 were prognostic factors. Multivariate analyses showed that histological type, T stage, N stage, M stage and mediastinal radiotherapy for ADC at stage N2 were independent prognostic factors., Conclusion: Besides T stage, N stage, and M stage, histological type and mediastinal radiotherapy for ADC at stage N2 are also independent prognostic factors of NSCLC after complete resection.

Background & Objective: Unexpected splenectomy is sometimes performed simultaneously with radical esophagectomy for esophageal carcinoma because of spleen injury or anatomical abnormity. This study was to investigate the influence of unexpected simultaneous splenectomy on postoperative complications and prognosis of patients undergoing radical esophagectomy for esophageal carcinoma., Methods: Clinical data of 843 esophageal carcinoma patients, underwent esophagectomy (R0 resection) at Cancer Center of Sun Yat-sen University from Aug. 1999 to Jul. 2002, were analyzed. Of these patients, 39 (4.6%) underwent splenectomy. The clinicopathologic parameters and prognosis of the patients in splenectomy group and non-splenectomy group were compared., Results: The amount of intraoperative blood loss was significantly higher in splenectomy group than in non-splenectomy group [(380+/-113) ml vs. (305+/-85) ml, P<0.001]. However, there were no significant differences in clinicopathologic characteristics, intraoperative or postoperative complications between the 2 groups (P>0.05). The occurrence rate of pulmonary complications was higher in splenectomy group than in non-splenectomy group (17.9% vs. 8.5%, P>0.05). The median survival time was shorter in splenectomy group than in non-splenectomy group (18.4 months vs. 21 months, P>0.05)., Conclusion: Unexpected simultaneous splenectomy had no effect on the long-term survival of patients who underwent radical esophagectomy for esophageal carcinoma, but it may result in more intraoperative blood loss and pulmonary complications.

Background & Objective: Esophagus is the most commonly involved site of extrapulmonary small cell carcinoma. However, no standard treatment has been established for primary esophageal small cell carcinoma. This study was to summarize the clinical characteristics, treatment, and prognosis of primary esophageal small cell carcinoma, and explore the impact of chemotherapy on the survival., Methods: The records of 33 patients with primary esophageal small cell carcinoma, treated in Cancer Center of Sun Yat-sen University from Jan. 1985 to Dec. 2005, were reviewed to summarize the clinical characteristics and impact of therapy modality on the survival. Prognostic factors were analyzed by Kaplan-Meier and log-rank method., Results: The median survival time of the 33 patients was 11.3 months; the 1-, 3-, and 5-year survival rates were 45.1%, 16.6%, and 3.5%, respectively. Clinical stage was the most important prognostic factor. The median survival time of the patients received local treatment (surgical operation or radiotherapy) was 6.3 months; the 1-, 2-, 3-year survival rates were 31.1%, 23.5%, and 8.2%, respectively. The median survival time of the patients received local treatment plus chemotherapy was 15.4 months; the 1-, 2-, 3-year survival rates were 69.3%, 34.6%, and 28.7%, respectively., Conclusion: Surgical operation plus chemotherapy can improve the survival of the patients with early stage primary esophageal small cell carcinoma.

Background & Objective: MCM4 belongs to minichromosome maintenance (MCM) protein family. It is a DNA replication licensing factor. This study was to explore the expression and significance of MCM4 in esophageal squamous cell cancer (ESCC)., Methods: The expression of MCM4 in 60 specimens of ESCC, paracancer esophageal epithelia, and distant normal esophageal epithelia was detected by reverse transcription-polymerase chain reaction (RT-PCR). The Correlations of MCM4 expression to clinicopathologic features of the 60 ESCC patients were analyzed., Results: The positive rate of MCM4 was significantly higher in ESCC than in paracancer esophageal epithelia (65.0% vs. 33.3%, P<0.001); MCM4 was not expressed or weakly expressed in distant normal esophageal epithelia. The positive rate of MCM4 was significantly higher in stage T3 ESCC than in stage T1 ESCC (73.7% vs. 25.0%, P<0.05). The expression of MCM4 had no correlations to grade, lymph node metastasis, sex, and age., Conclusion: The expression of MCM4 might be related to the pathologic stage of ESCC.

Background & Objective: Thymic epithelial tumors have a broad spectrum of biologic and morphologic features. This study was to assess the CT features of various subtypes of thymic epithelial tumors on the basis of the 1999 World Health Organization (WHO) classification., Methods: CT features of thymic epithelial tumors in 94 patients were retrospectively analyzed. All cases were confirmed histologically according to the 1999 WHO classification, including 7 cases of type A, 24 cases of type AB, 16 cases of type B1, 13 cases of type B2, 16 cases of type B3, and 18 cases of type C., Results: In the 94 cases, the long- and short-axis diameters of type A and type AB tumors were significantly shorter than those of type C tumors (P<0.05). All type A tumors had smooth contours, type A, AB, and B1 tumors were likely to have smooth contours (P<0.05), while type B3 and C tumors were likely to have irregular contours (P<0.05). Type A tumors had less necrotic areas than any other types (P<0.05). Multiple calcifications were more frequently seen in type B2, B3, and C tumors than in type A, AB, and B1 tumors (P<0.05). Homogeneous enhancement was more frequently seen in type A, AB, B1, and B2 tumors than in type B3 and C tumors (P<0.001). Type B3 and C tumors significantly preferred to infiltrate into mediastinal fat than any other types (P<0.05)., Conclusion: Though CT features of different subtypes of thymic epithelial tumors according to WHO classification are overlapped, short diameter, smooth contour, round shape, homogeneous density, and homogeneous enhancement are most suggestive for type A tumor; large diameter, irregular contour, necrosis and multiple calcifications in the lesion, heterogeneous enhancement, mediastinal fat infiltration, and great vessel infiltration are most suggestive for type B3 and C tumors.

Background & Objective: Esophageal stromal tumors and smooth muscle tumors are not easy to be distinguished in clinic though they have different pathologic features. This study was to compare the clinicopathologic features of esophageal stromal tumors and smooth muscle tumors, and discuss their treatments., Methods: The expression of CD117 and CD34 in 16 specimens of primarily diagnosed esophageal leiomyoma, 4 specimens of esophageal leiomyosarcoma, and 1 specimen of stromal tumor was detected by immunohistochemistry. The clinicopathologic features of the patients were analyzed, and the treatment principles and curative efficacies were summarized., Results: Of the 16 cases of primarily diagnosed esophageal leiomyoma, 5 were CD117(+) and finally diagnosed as non-high aggressive fatal stromal tumor according to the assessment criteria of stromal tumors; 11 were CD117(-). The stromal tumor was CD117(+) and CD34(+), and diagnosed as high aggressive fatal stromal tumor. The 4 cases of primarily diagnosed esophageal leiomyosarcoma were CD117(-) and CD34(-). There was no obvious difference in clinicopathologic manifestations, treatment and prognosis between esophageal non-high aggressive fatal stromal tumor and leiomyoma, and between esophageal high aggressive fatal stromal tumor and leiomyosarcoma., Conclusions: Esophageal stromal tumors and smooth muscle tumors can not be distinguished with clinicopathologic exhibitions. The immunohistochemical examination of antibody CD117 is necessary for identifying them. Lumpectomy or esophageal partial resection is enough for esophageal non-high aggressive fatal stromal tumor and leiomyoma. Esophageal partial resection is necessary for esophageal high aggressive fatal stromal tumor and leiomyosarcoma.

Background & Objective: During the reconstruction process of organs or tissues, different implant materials can lead to different healing results because of different extracellular matrix interfaces and tissue biocompatibilities. This study was to observe the regeneration process of "neo-esophagus"after implanting an artificial esophagus, and investigate its healing mechanism., Methods: Histopathologic studies on neo-esophagus in 1, 3, 6, 12, and 24 months after implantation were performed using gross-giant specimen technique and special staining methods. The processes of tissue molding and reconstruction, and regeneration of high-level cell organ in "neo-esophagus"were observed., Results: The artificial esophagus temporarily replaced the defective esophagus at the early stage after implantation, and dropped off about 1 month after operation. The epithelization of neo-esophagus induced by host tissue was completed about 3-6 months after operation. The submucous muscle layer, mucous glands, nerve fiber, and capillaries were reconstructed about 12 months after operation. The narrowing of "neo-esophagus" occurred about 3-6 months after operation and was relieved 12 months after operation., Conclusions: The implanted artificial esophagus made of bio-material can replace the defective esophagus at the early stage, and induce connective tissues, including collagen and fibroblasts, to deposit and cover on it to form neo-esophagus. The neo-esophagus is developed by epithelization and reconstruction of submucous muscle layer, mucous glands, nerve fiber, and capillaries 12 months after operation. The narrowing of "neo-esophagus" is caused by overgrowth and contraction of scars.

Objective: To observe the effect of the modified artificial esophagus on postoperative stenosis in dogs., Methods: The models of defected esophagus were established in dogs. The double-layered membrane tube (modifying type) was implanted in the test group (n = 10) and the esophageal stent was further inserted when the stenosis occurred. The single pattern tube (original type) was transplanted to the control group (n = 30). The dilation treatment was performed to relieve the postoperative stenosis; alternatively, the esophageal stent was implanted in the unsuccessful dogs., Results: The average artificial esophagus removal time was 19.10 days in the test group, which was significantly lower than 39.07 days in the control group (t = 15.6, P = 0.000). No obstruction after removal was observed in the experimental group. The incidence of postoperative stenosis had no significant difference between these two groups., Conclusion: The double-layered membrane tube can make the tube removal safer by shortening the removal time.

Background & Objective: Tyrosine kinase mediates cell proliferation and differentiation, and plays important roles in tumorigenesis and development of esophageal carcinoma. STI571 is a tyrosine kinase inhibitor of platelet-derived growth factor receptor beta (PDGFR-beta) which is overexpressed in esophageal carcinoma. This study was to explore the in vitro killing effects of STI571 on esophageal carcinoma cell lines CE-48T and CE-81T., Methods: The expression of PDGFR-alpha and PDGFR-beta in CE-48T and CE-81T cells was detected by Western blot. The killing effects of STI571 on CE-48T and CE-81T cells were evaluated by MTT assay. Cell apoptosis was analyzed by flow cytometry with Annexin V/PI labeling. The expression of p-PDGFR-beta was detected by Western blot before and after treatment of STI571., Results: CE-48T cells expressed PDGFR-beta, but did not express PDGFR-alpha; CE-81T cells did not express both PDGFR-alpha and PDGFR-beta. The 50% inhibitory concentration (IC50) of STI571 was significantly lower for CE-48T cells than for CE-81T cells [(8.32+/-1.50) micromol/L vs. (41.02+/-7.64) micromol/L, P=0.002]. When treated with 10 micromol/L STI571 for 12 h, the apoptosis rate of CE-48T cells was (52.43+/-5.30)%, but the apoptosis rate did not increase as the treatment time and concentration increased. After treatment of STI571, the expression of p-PDGFR-beta was inhibited in CE-48T cells, but didn't change in CE-81T cells., Conclusions: STI-571 could induce the apoptosis of PDGFR-beta-positive esophageal carcinoma CE-48T cells. p-PDGFR-beta might be the target of STI571.

Background & Objective: Some researches have showed that STI-571 could inhibit tyrosine kinase of Bcr-Abl, C-kit, and platelet-derived growth factor receptor-beta (PDGFRbeta), therefore, inhibit cell differentiation and proliferation and accelerate cell apoptosis. This study was to examine the expression of tyrosine kinase receptor C-kit and PDGFRbeta, which is correlated to STI-571, in esophageal carcinoma., Methods: The expression of C-kit and PDGFRbeta in tumor tissue, para-tumor tissue, and normal tissue of 50 specimens of esophageal carcinoma was examined by immunohistochemistry., Results: The strong expression rate of C-kit was low in tumor, para-tumor, and normal tissues (4%, 4%, and 12%, respectively), with no significant difference (P=0.220). The strong expression rate of PDGFRbeta was significantly higher in tumor tissues than in para-tumor and normal tissues (68% vs. 28% and 28%, P=0.001). Logistic regression analysis revealed that the strong expression rate of C-kit and PDGFRbeta had no correlation to sex, age, differentiation degree, infiltrative depth, position, lymph node metastasis, and stage of esophageal carcinoma., Conclusions: The strong expression rate of PDGFRbeta is significantly higher in tumor tissues than in para-tumor and normal tissues. The strong expression rate of C-kit in normal esophageal tissues is low, and it is lower in para-tumor and tumor tissues.

Background & Objective: The World Health Organization (WHO) histological classification of thymoma was published in 1999. This study was to investigate the correlations of WHO histological classification of thymoma to its clinical characteristics and prognosis., Methods: Records of 82 thymoma patients treated with surgery were reviewed retrospectively. Histological diagnosis based on WHO classification system was made by an experienced pathologist. The correlations of WHO histological classification of thymoma to its clinical characteristics and prognosis were analyzed., Results: Of the 82 cases, 5 (6.1%) were type A, 21 (25.6%) were type AB, 14 (17.1%) were type B1, 12 (14.6%) were type B2, 14 (17.1%) were type B3, and 16 (19.5%) were type C; according to Masaoka clinical staging system, 29 (35.4%) were in stage I, 13 (15.8%) in stage II , 32 (39%) in stage III , and 8 (9.8%) in stage IVa. The histological subtype of thymoma was significantly correlated with clinical stage (chi2 = 47.29, P < 0.001) and tumor invasive degree (chi2 = 30.78, P < 0.001). Complete resection rate was significantly higher in patients with type A, AB, B1 or B2 tumors than in patients with type B3 or C tumors (84.6% vs. 50.0%, chi2 = 11.29, P = 0.002). The 5-year survival rates of patients with stage I, II, III , and IVa were 100%, 100%, 69.5%, and 37.5%, respectively; the 10-57.1%, year survival rates were 88.1%, 47.5, and 0, respectively. The difference of survival rates among different clinical stages (log-rank = 40.31, P < 0.001) and histological subtypes (log-rank = 16.0, P = 0.007) were significant., Conclusion: To some extent, the WHO histological classification reflects the biological behavior and clinical characteristics of thymoma, and may be helpful in diagnosing and treating thymoma.

Background & Objective: Breast cancer may undergo metastasis in early phase. Distant metastasis, especially bone metastasis, may influence prognosis of breast cancer patients. Bone marrow micrometastasis (BMM) is difficult to detect with routine methods. This study was designed to evaluate expression and clinical significance of cytokeratin 19 (CK19) in bone marrow of patients with breast cancer., Methods: Expression of CK19 mRNA in bone marrows of 65 breast cancer patients, 15 benign breast disease patients, and 8 healthy volunteers was detected by reverse transcription-polymerase chain reaction (RT-PCR). Correlation of CK19 mRNA expression to clinicopathologic features of the 65 breast cancer patients was analyzed., Results: Positive rate of CK19 mRNA was 33.8% in the 65 breast cancer patients, and 0 in both benign breast disease patients and healthy volunteers. Expression of CK19 mRNA was positively correlated with tumor size and clinical stage (P < 0.05), but was not related to age and lymph node status (P > 0.05). In addition, positive rate of CK19 mRNA was positively correlated with carcinoembryonic antigen (CEA) in peripheral blood (r=0.372, P=0.002)., Conclusions: CK19 mRNA may be used as a molecular marker to detect bone marrow micrometastasis in patients with breast cancer. The detection may help to select proper therapy and predict prognosis of breast cancer patients.

Background & Objective: Small cell lung cancer (SCLC) is usually widely disseminated at the time of diagnosis due to its rapid growth. Therefore chemotherapy is the predominant form of treatment for SCLC. However, chemotherapy normally ended in failure as a consequence of recurrence of primary tumor or mediastinal lymphatic nodes. The objective of this study was to investigate whether combined surgical treatment for SCLC can control primary tumor more effectively and increase the survival of the patients., Methods: Fifty-one cases of limited SCLC treated with surgery from May 1981 to May 2001 in Cancer Center, Sun Yat-sen University were reviewed retrospectively., Results: According to 1997 international staging system, there were 7 patients with stage IB(13.7%), 5 with stage IIA(9.8%), 15 with stage IIB (29.4%), 20 with stage IIIA (39.2%) and 4 with stage IIIB (7.8%). Twelve patients received pneumonectomy, 35 lobectomy, 3 segmentectomy, and 1 exploration. Thirteen patients were treated with surgery alone and 38 of them combined with 2-6 cycles of pre- or post- operative chemotherapy. The median survival time was 20.8 months. The overall 1-, 3-, and 5-year survival rates were 43.0%, 25.9%, and 20.1%, respectively. The 1-, 3-, and 5-year survival rates for patients with stage IB were 100.0%, 80.0%, and 30.0% respectively, with stage II were 79.7%, 39.8%, and 34.5%, respectively, with stage III were 52.4%, 21.8%, and 5.46%, respectively. The 1-,3-, and 5-year survival rates for patients treated by surgery combined with chemotherapy were 77.5%, 38.5%, and 23.8% and that of surgery alone were 41.7%, 16.7%, and 8.3%, respectively (P< 0.01)., Conclusion: Combined surgical treatment can increase the survival rate of SCLC more effectively and should be considered as an important modality in multi-disciplinary treatment of limited small cell lung cancer.