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81.
82.
Although development of human anti-murine inununoglobulin antibody (HAMA) is often seen in patients receiving murine antibodies, the variety of methods used for detecting HAMA makes it difficult to compare directly the HAMA responses measured by different assays. In the present study, several parameters of the HAMA response to two murine monoclonal antibodies were evaluated. The anti-sialosyl Tn antibody MLS102 and anti-CA125 antibody 145-9, which were labeled with 111ln, were injected intravenously into 17 colorectal cancer patients and 11 ovarian cancer patients for immnnoscintigraphy, respectively. HAMA was measured by enzyme-linked immunosorbent assay. There was no difference in baseline HAMA levels before antibody injection between the two groups. HAMA developed more frequently in ovarian cancer patients receiving the 145-9 antibody than in colorectal cancer patients receiving the MLS102 antibody (9/11 vs. 6/17, P <0.05). No significant difference was observed in maximal HAMA levels between the two groups of patients. However, time to reach the maximal levels was delayed and the duration of the response seemed longer in ovarian cancer patients. Among 11 patients receiving the 145-9 antibody three patients became positive for HAMA more than 2 months after antibody injection and the other two had HAMA activity in their sera for more than 17 months. HAMA response was different between the two antibodies, and late onset or long duration of HAMA response against the 145-9 antibody suggests the importance of HAMA measurement in patients who receive a second injection of murine antibodies even after a long interval.  相似文献   
83.
BACKGROUND: Positron emission tomography (PET) using (18)F-fluoro-2-deoxy-D-glucose (FDG) has been used for the evaluation of various tumors, but accumulation in inflammatory lesions makes it a controversial modality. The aim of this study was to investigate the usefulness of delayed scanning in differentiation between malignant and benign lesions in the pancreas. METHODS: Forty-seven patients with suspected pancreatic carcinoma were studied by FDG-PET. All patients received approximately 370 megabequerels of FDG after a transmission scan, and an emission scan was performed 1 hour and 2 hours later for all patients. A subset of 19 patients was also scanned at 3 hours postinjection. The standardized uptake value (SUV) was determined, and the retention index was calculated by dividing the increase in the SUV between 1 hour and 2 hours postinjection by the SUV at 1 hour postinjection. RESULTS: Of 27 malignant lesions, the SUVs of 22 lesions increased at 2 hours postinjection, whereas the FDG uptake in 17 of 20 benign lesions decreased. The SUVs at 3 hours postinjection were higher than those at 2 hours postinjection in 9 of 14 malignant lesions and in 2 of 5 benign lesions. Malignant lesions showed a higher retention index than benign lesions (mean +/- standard deviation: 12. 36 +/- 13.37 and -7.05 +/- 17.28, respectively; P < 0.0001). Applying an SUV of 2.5 at 1 hour postinjection with the cut-off value for the differentiation between malignant and benign lesions caused one false negative result and seven false positive results, with a diagnostic accuracy of 83.0% (39 of 47 patients). However, combining the retention index with the SUV obtained at 2 hours postinjection provided a higher diagnostic accuracy (91.5%; 43 or 47 patients) than the SUV alone. The false negative rate remained constant when the retention index was taken into account. Images at 3 hours postinjection usually were unhelpful in differentiating further between malignant lesions and benign lesions. CONCLUSIONS: The current data suggest that delayed FDG-PET scanning at 2 hours postinjection may contribute to differentiation between malignant and benign lesions in the pancreas.  相似文献   
84.
Biweekly intravenous infusions of low-dose cisplatin (CDDP) and 5-fluorouracil (5-FU) were evaluated in 80 patients with advanced or recurrent gastric, colorectal, pancreatic or gallbladder adenocarcinoma. CDDP was given biweekly at a dose of 15 mg/m2 infused for 30 minutes, and 5-FU 375 mg/m2 was infused for 2 hours as many times as possible. The response rate among patients with gastric cancer was 26%, colorectal cancer 10%, pancreatic cancer 7.7%, and gallbladder cancer 42.9%. The response rates were not so high, but the median survival time of patients with recurrent gastric cancer was 17.3 months, pancreatic cancer 6.7 months, and gallbladder cancer 10.7 months. A patient with unresected advanced pancreatic head cancer with liver and para-aortic lymph node metastases received this therapy 38 times, and lived for 54 months. No severe side effects occurred in any of these cases. Thus, this chemotherapy could well be effective for the outcome of cases of advanced gastrointestinal carcinoma.  相似文献   
85.
Background:
Nine patients with a history of radical nephrectomy for renal cell carcinoma underwent surgical removal of newly detected pulmonary nodules at the Hiroshima University Hospital. Six patients had metastatic lung tumors two patients had bronchogenic primary carcinomas and one had a granulomatous infection.
Methods:
To determine if any characteristics can distinguish a new primary carcinoma from metastatic renal cell carcinoma, we reviewed the nine patients described above. The patients with pulmonary metastases and those with new primary lung cancers did not differ in age, sex, history of smoking, clinical stage and pathological findings of the renal primary site, on the location and size of the pulmonary nodules.
Results:
Only the interval between the nephrectomy and the appearance of the new pulmonary lesion may be a predictive factor. This interval was 48 and 51 months for the patients with new primary lung cancers but varied from 0 to 39 months for the patients with metastatic renal cell carcinoma. A solitary nodule had an equal chance of being metastatic or primary. Conclusions: These results indicate that a solitary nodule that is detected at a longer inferval after radical nephrectomy may be a new primary lung cancer. Once new pulmonary nodules are identified in a patient with a history of radical nephrectomy for renal cell carcinoma, surgical excision is required for a final diagnosis before initiating therapy for metastases.  相似文献   
86.
87.
BACKGROUND: In the present study we assessed whether expression of p53 protein or HPV DNA correlates with recurrence as well as several known prognostic factors in uterine cervical carcinoma. METHODS: Forty-nine patients with FIGO stage IA-IIB who underwent hysterectomy between 1998 and 2002 were retrospectively studied. All 49 cancer tissue samples were used for immunohistochemical study. Twenty-five of 49 cases were also examined by PCR-RFLP for detection and typing of HPV DNA. RESULTS: Twenty of 49 (40.8%) specimens demonstrated nuclear staining for p53. A significant association between p53 overexpression and age, hormonal status, FIGO stage, or recurrence was observed (p=0.02, 0.01, 0.03, 0.01). However, no significant association was found between p53 overexpression and lymph node metastases, parametrium involvement, or risk of death (p=0.18, 0.06, 0.14). Nineteen of 25 (76%) were HPV DNA-positive and 6 (24%) were negative. Discussion: There was no relation between HPV DNA positivity and age, FIGO stage, lymph node metastases, parametrium involvement, recurrence, or risk of death. CONCLUSION: p53 overexpression is associated with age, hormonal status, FIGO stage, and recurrence in uterine cervical carcinoma.  相似文献   
88.
Chemotherapies for recurrent gastric cancer have not yet been established. Here we report a case of type 4 gastric cancer associated with lymphangitis carcinomatosis which became refractory to the previous chemotherapies. The case was a 40-year-old woman. She had been diagnosed with gastric cancer after a Krukenberg tumor operation. Chemotherapies (TS-1 plus CDDP as first-line, and TS-1 plus taxanes as second-line) were performed, and a partial response was achieved. Disease activity has been well controlled until this time. Since recurrence of left pleural effusion and lymphangitis carcinomatosis was recognized, we changed the chemotherapy TS-1 plus CPT-11. Pleural effusion decreased and lymphangitis carcinomatosis improved. The serum CA 19-9 level rose transiently after CPT-11 administration, and tended to fall at the second week of chemotherapy. However, the patient died 2 years 4 months after the onset. TS-1 plus CPT-11 combination chemotherapy would be effective for lymphangitis carcinomatosis and also useful as third-line chemotherapy for recurrent gastric cancer.  相似文献   
89.
The effects of in utero and lactational exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on brain sexual differentiation were investigated. TCDD was orally administered to pregnant Holtzman rats on gestation day (GD) 15, and the activity of brain aromatase, a key enzyme for sexual differentiation, was measured in offspring on postnatal day (PND) 2. Changes in sexual dimorphisms of saccharin preference and the volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) were examined in adult offspring. In controls, litter means of brain aromatase activity were higher in males than in females. In utero exposure to 200 ng/kg TCDD significantly decreased the sex ratio of aromatase activity (male/female) on PND 2. Offspring were weaned on PND28 and the saccharin test was started on PND84. In controls, saccharin (0.25%) intake (g/kg body weight) was significantly higher in female offspring than in males. In utero exposure to 200 ng/kg TCDD significantly increased saccharin intake in male offspring compared with control males, whereas 800 ng/kg TCDD had no effect. Neither dose of TCDD influenced saccharin intake of female offspring. In controls, SDN-POA volume was significantly greater in males than in females at 14 weeks of age. Exposure to 200 ng/kg TCDD significantly decreased SDN-POA volume in males, whereas 800 ng/kg TCDD had no effect. Neither doses of TCDD influenced the SDN-POA volume in female offspring. These results suggest that in utero and lactational TCDD exposure dose-dependently induces demasculinization in male offspring by inhibiting brain aromatase activity in the hypothalamus-preoptic area during central nervous system development.  相似文献   
90.
After renal transplantation, persistent glomerular disease affecting the native kidneys typically causes albuminuria, at least for a period of time, making it difficult to determine in a noninvasive fashion whether proteinuria originates in the native kidneys or the renal allograft. To address this problem, dynamic contrast-enhanced magnetic resonance imaging (MRI) using gadolinium (Gd)-based albumin-bound blood pool contrast agent (MS325) to localize proteinuria was investigated. Glomerular proteinuria was induced in Sprague-Dawley rats by intravenous injection of puromycin aminonucleoside (PAN), whereas control rats received physiologic saline vehicle. Both groups of animals underwent a 40-min dynamic contrast-enhanced MRI using radio frequency spoiled gradient echo imaging sequence after injection of Gd-labeled MS325. Contrast uptake and clearance curves for cortex and medulla were determined from acquired MR images. Compared with controls, proteinuric rats exhibited significantly lower elimination rate constants. The use of gadopentetate dimeglumine (Gd-DTPA) as a contrast agent showed smaller and less specific differences between proteinuric and control groups. In rats with one proteinuric kidney (PAN-treated) and one normal kidney (transplanted from a normal rat), MRI using MS325 was able to differentiate between the two kidneys. The results suggest that MRI with an albumin-bound blood pool contrast agent may be a useful noninvasive way to localize proteinuria. If this technique can be successfully applied in human patients, it may allow for the localization of proteinuria after kidney transplant and thereby provide a noninvasive way to detect disease affecting the renal allograft.  相似文献   
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