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High-resolution MR imaging for nodal staging in rectal cancer: are there any criteria in addition to the size? 总被引:19,自引:0,他引:19
PURPOSE: MR staging of nodal metastases in patients with rectal cancer using criteria based on size, shape and signal intensity can be difficult, because > or =50% of the nodes are less than 5 mm in size. Therefore new MR criteria were evaluated to see whether it can improve the MR assessment of nodal metastases in rectal cancer patients. MATERIALS AND METHODS: Ninety-nine patients with primary rectal carcinoma underwent 1.5 T high-resolution MRI with a quadrature phased array coil. Among them, 75 patients who had undergone total mesorectal excision were enrolled in this study. An MR radiologist, blinded for the histological results, randomly recorded the characteristics of each detectable node (LN); common criteria such as short-axis diameter, the ratio of long- to short-axis diameter, and signal intensity on each sequence; new criteria such as the margin (smooth, lobulated, spiculated, indistinct), a homogenous or mottled heterogeneous appearance, gross enhancement and its pattern, the venous encasement, and the dirty perirectal fat signal. RESULTS: Among 75 patients, 22 (29%) were node-positive. All patients who did not have detectable LN on MR were node-free (n = 15). Presence of LNs > 4 mm was significantly higher in the node-positive group. Presence of LNs > 8 mm was seen only in the node-positive group. Presence of a spiculated border and an indistinct border shows sensitivities of 45 and 36%, and specificities of 100 and 100%, respectively. Presence of a mottled heterogeneic pattern shows a sensitivity of 50%, a specificity of 95%. The presence of these three features were strongly correlated with LN positivity (P < 0.001, respectively). Presence of a venous encasement (n = 4) and dirty perirectal fat signal (n = 3) were also significantly (P < 0.05, respectively) correlated with LN positivity. CONCLUSION: In addition to size, new criteria such as a spiculated or indistinct border and a mottled heterogeneous appearance could be useful to predict regional lymph node involvement in patients with rectal cancer. 相似文献
995.
Miranda ML Oliveira-Filho AG Lemos-Marini SH Guerra G Bustorff-Silva JM 《Journal of pediatric surgery》2004,39(7):1030-1033
Background/Purpose
Stenosis of the vaginal introitus is the most frequent complication after genital reconstruction for ambiguous genitalia associated with congenital adrenal hyperplasia (CAH). With the aim of enlarging the vaginal introitus, the authors present a technical modification of the introitoplasty that uses a bilateral cutaneous island flap based on the perineal superficial branches of the internal pudendal artery.Methods
Eleven girls with CAH and Prader III to V genital ambiguity were included. Feminizing genitoplasty was performed in 1 stage. Bilateral cutaneous labioescrotal island flaps, based on the posterior labial artery, were included in the introitoplasty. The cosmetic results of the genitoplasty were evaluated by photographic analysis of the external genitalia.Results
Integrity of the vaginal introitus as well as excellent integration of the flap and absence of additional scars in the donor area were assessed in all girls.Conclusions
This modified island flap is technically feasible and reproducible producing no additional sequels in the donor area. It uses perineal skin that is usually excised in other techniques avoiding the use of harvesting skin from adjacent areas. Thus, it can be a useful additional procedure in the introitoplasty in association with the currently used techniques. 相似文献996.
997.
Superior survival and proliferation after transplantation of myoblasts obtained from adult mice compared with neonatal mice 总被引:6,自引:0,他引:6
BACKGROUND: Myoblast transfer therapy (MTT) is a strategy designed to compensate for the defective gene in myopathies such as Duchenne muscular dystrophy (DMD). Experimental MTT in the mdx mouse (an animal model of DMD) has used donor myoblasts derived from mice of various ages; however, to date, there has been no direct quantitative comparison between the efficacy of MTT using myoblasts isolated from adult and neonate donor muscle. METHODS: Donor normal male myoblasts were injected into Tibialis Anterior muscles of dystrophic female host mice and the survival and proliferation of male myoblasts quantitated using Y-chromosome specific real-time quantitative polymerase chain reaction. The survival of late preplate (PP6) myoblasts derived from neonatal (3-5 days old) or adult (6-8 weeks old) donor mice after MTT were compared. The influence of the number of tissue culture passages, on survival post-MTT, was also evaluated for both types of myoblasts. RESULTS: Surprisingly, superior transplantation efficiency was observed for adult-derived compared with neonatal myoblasts (both early and late passage). Extended expansion (>17 passages) in tissue culture resulted in inferior survival and proliferation of both adult and neonatal myoblasts; however, proliferation of early passage myoblasts (both adult and neonate) was evident between 3 weeks and 3 months. CONCLUSIONS: Myoblasts derived from neonatal mice were inferior for transplantation, and early passage donor myoblasts from adult mice are recommended for MTT in this model. 相似文献
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999.
Antonelli A Tanello M Zanotelli T Frego E Tardanico R Cosciani Cunico S 《Urologia internationalis》2004,72(1):79-81
Bladder myofibroblastic inflammatory tumors are rare benign proliferative lesions that can simulate both urothelial and connective tissue malign neoplasms, making a preoperative diagnosis nearly impossible. Conservative treatment appears to be curative, even though local recurrences have been reported, and so malignancy should be ruled out above all by means of an accurate follow-up. Two cases are described, 1 of which with the longest follow-up period reported so far (8 years). 相似文献
1000.
Evaluation of magnetic fluid hyperthermia in a standard rat model of prostate cancer 总被引:4,自引:0,他引:4
Johannsen M Jordan A Scholz R Koch M Lein M Deger S Roigas J Jung K Loening S 《Journal of endourology / Endourological Society》2004,18(5):495-500
PURPOSE: To examine the feasibility and potential of magnetic fluid hyperthermia (MFH) as a minimally invasive method for hyperthermia treatment of prostate cancer. MATERIALS AND METHODS: Orthotopic Dunning R3327 prostate tumors were induced in 20 male Copenhagen rats. The animals either received MFH treatment following intratumoral administration of magnetic fluids or were used as either tumor growth controls for determination of iron distribution in selected organs or as histologic controls without MFH treatment. The MFH treatments were carried out at 45 degrees C or 50 degrees C using an AC magnetic field applicator system designed for small animals. RESULTS: Sequential treatments with MFH were possible following a single intratumoral injection of magnetic fluid. Intratumoral temperatures of 50 degrees C and more were obtained and were monitored online using fluoro-optic thermometry. Four days after MFH treatments, 79% of the injected dose of ferrites was still present in the prostate. CONCLUSIONS: The successful intraprostatic nanoparticle infiltration and stable steady-state intratumoral treatment temperatures demonstrate the feasibility of MFH in a prostate cancer model. Efficacy and survival benefit must be confirmed in further experiments. 相似文献