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91.
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs.  相似文献   
92.
We report a case of anal canal cancer in a 65-year-old woman who had complained of bloody stool. Physical examination revealed a 2.5 cm ulcerated tumor in the anterior wall of the anal canal astride the dentate line. Histological examination of biopsy specimens confirmed the diagnosis of moderately differentiated squamous cell carcinoma. Chemoradiation therapy included whole pelvic irradiation amounting to 4140 cGy followed by conformal boost irradiation of 2000 cGy and 5-fluorouracil div 750 mg/24 hr 3 days, mitomycin C iv 10 mg day 1, and cisplatinum div 50 mg day 2. Six weeks later the tumor had completely regressed, and there was no evidence of recurrence 21 months later. Her anorectal function was retained.  相似文献   
93.
BACKGROUND: Intraoperative assessment of small intestinal viability following ischemic insult from arterial occlusion has remained difficult. The purpose of the present study was to assess the applicability of non-contact tissue blood flowmeter (NCLBF) with regard to intraoperative assessment of intestinal viability. METHODS: Using the ischemia-reperfusion model of rabbits, the relationship between the records of NCLBF, pulse oximetry (PO), and histological grade and the comparison of accuracy of intestinal viability among NCLBF, PO, and fluorescein (FL) were examined. RESULTS: There was a significant relationship between NCLBF and the histological grade (coefficient-0.80, P <0.0001); however, PO was not related. The accuracy and sensitivity of bowel viability of NCLBF (76%, 88%) were better than those of PO (58%, 23%) and FL (48%, 4%), respectively (P <0.001). CONCLUSIONS: NCLBF is useful to assess intestinal viability, suggesting the possibility of clinical use.  相似文献   
94.
BACKGROUND: In surgical repair of abdominal aortic aneurysm (AAA), excessive bleeding which causes postoperative complications is sometimes observed. To determine the risk factors of perioperative excessive blood loss, this retrospective study was performed. METHODS: Design. A retrospective study. Setting. An academic medical center. Participants. One hundred and forty patients underwent elective surgical repair of an abdominal aortic aneurysm (AAA) at our institution from 1995 through 1997. Measurements. The present study includes critical review of 140 consecutive charts of patients undergoing elective surgical repair of AAA. Preoperative laboratory data, intraoperative data and amount of blood loss to identify risk factors of perioperative blood loss. Factors which were found to be significantly associated with the amount of perioperative blood loss were preoperative plasma fibrin degradation product (FDP) level (r=0.445), amount of immediate re-infusion of shed blood (r=0.438), and duration of operation (r=0.411). RESULTS: Preoperative fibrinogen level correlated with perioperative blood loss little (r=-0.187). Preoperative platelet count or the other coagulation profile did not affect the amount of perioperative blood loss. The patients whose preoperative FDP were more than 40 microg x ml(-1) significantly increased the risk of excessive blood loss compared with less than 40 microg x ml(-1). CONCLUSIONS: The significant preoperative risk factor of perioperative blood loss was only FDP level in present study. Especially, the patients whose preoperative FDP were more than 40 microg x ml(-1) increased the risk of excessive blood loss.  相似文献   
95.
96.
Summary Purpose: The aim of this study was to identify the predictors of the response to doxorubicin plus cyclophosphamide in patients with recurrent breast cancer (RBC) previously treated with anthracycline-containing regimens in a neoadjuvant or adjuvant setting. Method: Between December 1993 and October 2005, 664 patients had received combined doxorubicin plus cyclophosphamide chemotherapy (doxorubicin, 40 mg/m2, iv on day 1; cyclophosphamide, 500 mg/m2, iv on day 1, every 21 days) for RBC at our institution. In this study, we retrospectively analyzed the efficacy of doxorubicin plus cyclophosphamide in 99 of these 664 RBC patients who had also previously been administered an anthracycline-based chemotherapy in a neoadjuvant or adjuvant setting. Results: The median cumulative dose of the previously administered anthracycline was 156 mg/m2. The median disease-free interval (DFI) and median anthracycline-free interval were 33.8 and 43.7 months, respectively. The overall response rate to doxorubicin plus cyclophosphamide therapy was 38.4% (95% CI; range, 28.8–48.0%). The median time to progression and overall survival were 6.2 and 17.5 months, respectively. The results of a multivariate logistic regression analysis revealed a significant association of the response to doxorubicin plus cyclophosphamide therapy with the DFI (P = 0.02); human epidermal receptor type 2 (HER2) status also tended to affect the response rate, however the association was not statistically significant (P = 0.06). Conclusion: DFI and HER2 status may be associated with the response to repeat utilization of anthracycline-containing regimens in RBC patients also treated previously with anthracycline-containing chemotherapeutic regimens in a neoadjuvant or adjuvant setting.  相似文献   
97.
98.
Maxillary squamous cell carcinomas staged by computed tomography   总被引:1,自引:0,他引:1  
In 72 patients with maxillary squamous cell carcinoma, computed tomography (CT) alone was used for T-staging according to the AJC classification. Five, 31, and 36 tumors were diagnosed as T2, T3, T4, respectively. In N0 patients with a minimum follow-up of 2 years, local control rates for T2, T3, and T4 tumors were 33% (1/3), 64% (16/25) and 38% (9/24), respectively. Addition of maxillectomy to treatment seemed to have improved the local prognoses in T3 and T4 tumors. High radiation doses of 60 Gy or more seemed to be beneficial for patients with T3 tumors and without maxillectomy. CT will be of great help in classifying tumors objectively. But more importantly, it will reveal resectability and dictate treatment of choice by delineating the tumor extent precisely.  相似文献   
99.

Background

Prediction of prognosis is important for patients so that they can make the most of the rest of their lives. Oncologists could predict survival, but the accuracy of such predictions is unclear.

Methods

In this observational prospective cohort study, 14 oncologists treating 9 major adult solid malignancies were asked to complete questionnaires predicting survival based on performance status, oral intake, and other clinical factors when patients experienced progressive disease after standard chemotherapies. Clinically predicted survival (cps) was calculated by the oncologists from the date of progressive disease to the predicted date of death. Actual survival (as) was compared with cps using Kaplan–Meier survival curves, and factors affecting inaccurate prediction were determined by logistic regression analysis. The prediction of survival time was considered accurate when the cps/as ratio was between 0.67 and 1.33.

Results

The study cohort consisted of 75 patients. Median cps was 120 days (interquartile range: 60–180 days), and median as was 121 days (interquartile range: 40–234 days). The participating oncologists accurately predicted as within a 33% range 36% of the time; the survival time was overestimated 36% of time and underestimated 28% of the time. The factors affecting the accuracy of the survival estimate were the experience of the oncologist, patient age, and information given about the palliative care unit.

Conclusions

Prediction of cps was accurate for just slightly more than one third of all patients in this study. Additional investigation of putative prognostic factors with a larger sample size is warranted.  相似文献   
100.
A 72-year-old woman presented with gradually-worsening myalgia and muscle weakness of the proximal lower limbs as well as elevated serum creatine kinase level. Based on a clinicoseropathological examination including a muscle biopsy, she was diagnosed with anti-signal recognition particle (SRP) myopathy. Although the myopathy relapsed two times in two years under oral prednisolone and intravenous immunoglobulin therapy, the myopathy remained in remission for more than three years after resection of gastric cancer. Although the anti-SRP myopathy is not considered to be cancer-associated in general, we should note that some cases of anti-SRP myopathy may be ameliorated with appropriate cancer treatment.  相似文献   
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