Persistent and aggressive treatment for thymic carcinoma. Results of a single-institute experience with 25 patients

OBJECTIVES: The aim of this study is to retrospectively evaluate the role of several therapies, mainly chemotherapy, for thymic carcinoma (TC). METHODS: From July 1973 to July 2005, 25 patients (15 males and 10 females) with histologically proven TC were treated at our department. The median age of the patients was 59 years, with a range of from 30 to 78 years. According to Masaoka's staging system, there was 1 stage I patient, 3 stage II, 7 stage III, 6 stage IVa, and 8 stage IVb patients. The histological subtype was in all cases squamous cell carcinoma, nonkeratinizing type. RESULTS: There were 6 complete surgical resections, 1 incomplete resection followed by chemoradiotherapy, 6 with radiotherapy alone, 3 with radiotherapy plus chemotherapy, and 9 with chemotherapy alone as the initial treatment. Eighteen patients were administered second-line therapy. The regimen obtaining the best response rate was doublet chemotherapy consisting of carboplatin (CBDCA) and paclitaxel. The median survival time and survival rate at 5 years for the patients excluding surgical cases with stage I/II disease were 32 months and 31%, respectively. CONCLUSION: The doublet of CBDCA and paclitaxel thus appears to be a promising regimen for TC and further investigation in a multi-institutional phase II trial is, therefore, strongly called for.     

Hepatic lesion of invasive thymoma: possibility of direct invasion

Thymomas grow slowly but tend to invade the surrounding tissue. We herein report four patients with hepatic lesions of thymomas, which were thought to have directly invaded the liver. These patients had received combined modality treatments throughout the clinical course, and the hepatic lesions appeared a long time after the initial treatment – 11.8 years on average. In these patients, the prognoses after the appearance of hepatic invasion were poor. Appropriate local control in the early stages of the clinical course may therefore be essential for preventing the extrathoracic spread of invasive thymoma.     

Resin-based micropipette tip for immunochromatographic assays in urine samples

A novel bioanalysis system based on immunochromatography was developed in connection with a nitrocellulose resin modified micropipette tip, such as ZipTip. The sandwich-type immunoassay was applied to our bioanalysis system. The simple handling of the micropipette enabled us to increase the sample volume and detect low concentrations of target antigens in urine samples. In addition, the washing procedure could also be performed easily to reduce the background signal levels. For analytical evaluations, the color intensity was captured by a flatbed scanner, and processed by a software. We have achieved the detection of human chorionic gonadotropin (hCG) and prostate-specific antigen (PSA). The detection limit of hCG was 0.5 ng/ml (0.05 ng/tip), which is comparable to that of other conventional immunochromatographic systems. Moreover, the detection of PSA was greatly improved over the existing systems with the application of different sample volumes, such as 1 ng/ml (0.2 ng/tip) in a 200 microl sample volume, and 1 ng/ml (0.3 ng/tip) in 300 microl sample volume. Our bioanalysis system is a promising candidate for application to point-of-care tests with its simple handling and high sensitivity.     

Rapid Induction of Endometrial Carcinoma in ICR Mice Treated with N-Methyl-N-nitrosourea and 17β-Estradiol

The present study was undertaken to develop an animal model for endometrial neoplasms. A total of 107 female ICR mice, 10 weeks of age, were used and treated as follows: Group 1 (31 mice) was given intravaginal instillation of N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body wt.) once a week for three weeks and then fed diet containing 5 ppm 17/β-estradiol (E₂) for 20 weeks, starting one week after the last exposure to MNU, Group 2 (30 mice) was given MNU alone. Group 3 (31 mice) was given E₂ diet alone. Group 4 (15 mice) was fed the basal diet alone and served as the untreated control. At the termination of the experiment (week 23), all surviving mice were killed. Histopathological examination revealed that adenocarcinomas in the uterine corpus developed in mice of Groups 1-3, with a high incidence of endometrial hyperplasia. The incidence of endometrial carcinomas in Group 1 (15/31, 48%) was significantly higher than in Group 2 (2/29, 7%, P < 0.001) or Group 3 (7/31, 23%, P > 0.01). In the uterine cervix, small numbers of squamous cell carcinomas and pre-neoplastic lesions (dysplasias and hyperplasias) were also present in mice of Groups 13. In Groups 1 and 3, an increased E₂/progesterone (P) ratio was observed. Thus, the results indicated that this medium-term model for endometrial neoplasms is useful for studying the pathogenesis of endometrial cancer and that an increased E₂/P ratio is an important factor for the development of endometrial adenocarcinoma.