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C C Yuan

Publications and source records attributed to C C Yuan.

At least 19 recordsLinked to original sources
PubMed2005

Radical hysterectomy: past, present, and future.

After an analysis of 3,441 radical hysterectomies performed in our department, we found, after modification of the operative technique in 1983, the more lateral the excision the less the recurrence rate. The recurrence rate for Stage 1b-2a and Stage 2b patients comparing the years before 1983 to the years after decreased to 12.4% from 15.7% (158/1,006 vs 268/2,163; p = 0.009) in Stage 1b-2a and 24.6% from 55.8% (38/68 vs 47/191; p = 0.0007) in Stage 2b, respectively. With the modern trend of aspiring for an easier lifestyle, most physicians practice earlier. Therefore only very few physicians study radical hysterectomy. As the skill of surgery needs a longer period of education and training, it may only interest physicians who work with medical professionals as part of a team at a medical center. In the future, we should provide gynecological residents not only with a training program using the classic textbooks, but also with different points of view on changes and developments in radical hysterectomy. We hope to promote an attitude of offering patients access to different choices and opportunities of therapy. Radical hysterectomy is in fact a treatment option for patients with bulky cervical lesions and Stage 2b in particular.

Female↗
PubMed2003

The assessment of stability and reliability of a virtual reality-based laparoscopic gynecology simulation system.

PURPOSE OF INVESTIGATION: Surgeons require practiced skills in laparoscopic surgery. A virtual reality-based simulator system was developed for extensive training. The purpose of this study was to assess the feasibility of a virtual reality-based laparoscopic gynecology simulation system. METHODS: Laparoscopic tools and three-dimensional virtual environments were included in the simulation system. Ten healthy, non-disabled volunteers were recruited. The surgical procedure is a process of tubal sterilization by cauterization. Volunteers followed the training procedure, 15 trials in the first test and retest, respectively. RESULTS: Stable performances were obtained after about seven trials for all subjects. The intraclass correlation coefficients were 0.935 and 0.425 for task time and error frequency, respectively. CONCLUSION: The results of this study indicate that the system is stable and has a fair high test-retest reliability. Therefore, the VR-based laparoscopic gynecology system is feasible.

Adult↗
PubMed2003

Improved early detection of cervical intraepithelial lesions by combination of conventional Pap smear and speculoscopy.

PURPOSE: To evaluate the efficacy of the addition of speculoscopy to a Pap smear in cervical cancer screening. METHODS: All women were screened using the Pap smear plus speculoscopy (PapSure) and colposcopy in the multicenter trial. The final diagnosis of each patient was based on a histological evaluation of the colposcopic target biopsy. Results were analyzed using a proportional compare test, sensitivity, specificity and predictive value with significant value determined at less than 0.05. RESULTS: Of 1,717 eligible cases, 26 cases had LGSIL and 16 cases had HGSIL. Of the Pap smears, five cases had LSIL and 14 cases had HGSIL. Of the combination of the PapSure, 23 cases had LGSIL and 16 cases had HGSIL. The sensitivity of the Pap smear to that of PapSure was calculated at 45.2% and 92.9%, respectively (p < 0.001). The estimated cost to detect a cervical lesion using PapSure is less than that of the Pap smear. CONCLUSION: The addition of speculoscopy along with a Pap smear screening results in early detection of cervical lesions in comparison to the Pap smear alone. This screening combination is also more cost-effective and requires fewer visits to the clinic in comparison to a Pap smear screening alone.

Adult↗
PubMed2002

Both TPA and SCC-Ag levels are prognostic even in high-risk stage Ib-IIa cervical carcinoma as determined by a stratification analysis.

OBJECTIVE: To determine the prognostic values of tissue polypeptide antigen (TPA), squamous cell carcinoma antigen (SCC-Ag), and carcinoembryonic antigen (CEA) in the sera of cervical carcinoma patients, especially in those with a poor prognosis. METHODS: In this retrospective study, the preoperative serum SCC-Ag, TPA, and CEA were analyzed in 779 patients with cervical squamous cell carcinoma of stage Ib-IIa who received radical hysterectomy and pelvic lymph node dissection (RAH-PLND) between 1984 and 1994. RESULTS: Due to poor predictive value and poor correlation between serum CEA and clinico-pathological factors, CEA was abandoned in this study. Elevated TPA and SCC-Ag levels, pelvic lymph node metastasis (PLNM), lymphvascular space involvement (LVSI) and deep stromal invasion (DSI) were associated with poor survival time by univariate analysis. The correlation study showed that elevated serum TPA was significantly related to PLNM, LVSI, and DSI (p = 0.004, 0.008, and 0.021, respectively), and SCC-Ag was related to PLNM and bulky tumor size (p = 0.001 and 0.02, respectively). In the multivariate analysis, only PLNM and LVSI remained independently significant indicating poor survival. Further stratification studies by PLNM and LVSI showed that elevated TPA levels could even indicate higher recurrence rates in patients with PLNM (p = 0.045), as well as SCC-Ag in patients with LVSI (p = 0.038). CONCLUSIONS: The results suggest that both elevated TPA and SCC-Ag levels depicting poor prognosis in stage Ib-IIa cervical SCC, especially indicates a group of high-risk patients who may need more aggressive therapy.

Adult↗
PubMed2002

Extramammary Paget's disease found by abnormal vulvar brush sampling.

INTRODUCTION: Doctors are usually reluctant to perform a vulvar biopsy on a patient with non-specific chronic vulvitis--especially because of the rarity of vulvar malignancy in young women--until the lesion is suspected of being malignant. Therefore, most cases of extramammary Paget's disease (EMPD) were originally misdiagnosed as chronic and recurrent vulvar lesions. Late diagnosis of invasive lesions occurring in elderly females have resulted in cases of death. CASE: A 37-year-old patient showed an extended lesion on the vulva and perineum. In addition, abnormal cells were found from a vulvar scrape smear, and a following punch biopsy was used to diagnose and determine the extension of the disease. CONCLUSION: Diagnosis and demarcation of EMPD remain difficult due to the multifocal lesions and subtle nature of the disease. Brush sampling taken from suspicious areas can be a guide for multiple biopsies to demarcate the lesion before major surgery. A brush biopsy is presented as a first-step method to detect vulvar malignancy.

Adult↗
PubMed2002

Intraperitoneal cancer spread after laparoscopic cystectomy for mature teratoma with malignant transformation.

Laparoscopic surgery for ovarian dermoid cysts has been accepted. However, its potential limitations should be considered, including technique difficulty, intraoperative tumor spillage and malignant transformation. We report a case of ovarian dermoid cysts with malignant transformation that was initially treated using laparoscopic cystectomy, but was complicated by intraperitoneal tumor dissemination.

Adult↗
PubMed2002

Radioimmunodetection of cervical carcinoma xenografts with (111)In-labeled MAb Cx-99 detected by a hand-held gamma detector.

PURPOSE: To establish a radioimmunodetection (RAID) system for localization of cervical cancer by labeling 111-indium ((111)In) to a monoclonal antibody against cytokeratin 19 (MAb Cx-99), and detecting it with a hand-held gamma detector in an animal model. METHODS: MAb Cx-99 was labeled with 111-Indium by the DTPA chelating method. From the second day to the seventh day after injection of this immunoconjugate into athymic nude mice bearing cervical cancer cell line CC7T xenografts, the biodistribution ratios of tumor and non-tumor radioactivity were detected by a hand-held gamma detector. Data were also correlated with the data detected by the conventional gamma counter. RESULTS: The labeling efficiency of this (111)In-labeled MAb Cx-99 and (111)In-labeled MOPC was 91.6% and 95.5%, respectively. After injection, the liver, kidney and lung were initially noticed to have high radioactivity, but the localization of tumor/tissue ratios increased progressively as time passed, indicating the effect of delayed detection for distinguishing tumor from non-tumor tissues. Except for the spleen, the range of tumor/tissue ratios was 1.18-32.7 and 1.14-39.35 for the fourth day and the seventh day, respectively. The tumor/spleen ratio remained low until the seventh day after injection, thus indicating that the spleen might have a different excretion rate. CONCLUSION: This study indicated the feasibility of a hand-held detection system in the localization of cervical cancer after injection of (111)In-labeled MAb Cx-99. The effect of delayed detection was obvious by the decreasing high bindings in the liver, spleen and kidney, with the applicable detection time being four to seven days after injection.

Animals↗
PubMed2002

Different enzyme activities of sialyltransferases in gynecological cancer cell lines.

PURPOSE: Due to rarity of a relationship between sialyltransferase enzyme activities and gynecological cancers, we arranged the study to evaluate sialyltransferase enzyme activity in the various kinds of gynecological cancer cell lines. METHODS: Ten cell lines from various kinds of gynecological cancers and two cell lines from normal tissue were enrolled in this study. The activities of each subtype of sialyltransferases were detected using Gal beta1,3GalNAc-acetyl-lactosamine)-Obz1 (acceptor for ST2,3Gal I), Gal beta1,3GlcNAc beta1,3Gal beta1,4GlcNAc (acceptor for ST2,3Gal III), Gal beta1,4GlcNAc (acceptor for ST2,3Gal IV), asialo-bovine submaxillary mucin (acceptor for ST2,6GalNAc I), asialo-fetuin (acceptor for STalpha2,6GalNAc II), and fetuin (acceptor for ST2,6GalNAc III), respectively. The amounts of sialic acids were measured using fluorescein-conjugated Sambucus nigra agglutinin (SNA) specific for alpha2,6-sialic acids and fluorescein-conjugated Maackia Amurensis agglutinin (MAA) specific for alpha2,3-sialic acids. RESULTS: The activities of two sialyltransferase subtypes, ST3Gal I & ST6GalNAc II, were significantly higher in nearly all cell lines. More specifically, cervical cancer cell line-ME 180, ovarian cancer cell line-ES-2, and choriocarcinoma cell line-BeWo showed high levels of ST3Gal I enzyme activity; all gynecological cancer cell lines except endometrial cancer cell line-RL95-2 had high levels of ST6GalNAc II enzyme activity when compared with a normal control cell line--fibroblast cell line (CCD-966Sk). Cell lines tested in this study have diverse levels of surface alpha2,6-sialic acid sugar chains (enhanced SNA binding) when compared with alpha2,3-sialic acid sugar chains (enhanced MAA binding) but we found that some cell lines such as Ca Ski (cervical cancer cell line), CC7T (cervical cancer cell line), PA-I (ovarian cancer cell line), and BeWo showed significantly altered cell surface alpha2,6-sialic acid sugar chains. CONCLUSION: Increasing enzyme activity of ST3Gal I and ST6GalNAc II might be important in various kinds of gynecological cancers. More specifically, enhanced activity of sialyltransferases involving alpha2,6-sialic acid sugar chains might be more important in cancer development. Future studies will investigate whether the enzyme activity of these sialyltransferases can be helpful for clinical practice.

Female↗
PubMed2002

Correlation of three-dimensional tumor volumetry with cervical cancer prognostic parameters.

OBJECTIVE: Estimation of tumor size by a single diameter is used in the current Federal International Gynecology Oncology (FIGO) cervical cancer staging system. However, the role of three-dimensional volumetry is rarely mentioned. In this study, three kinds of tumor volume estimations were performed and the relationship of these volume estimations among associated cervical cancer prognostic parameters were evaluated. METHODS: Thirty patients with newly diagnosed cervical cancer at Taipei Veterans General Hospital were enrolled in the study. Final pathology and associated parametric information was obtained by chart review. The original magnetic resonance (MR) image was reappraised by an experienced radiologist and the tumor volume was estimated using either three axial measurements or the longest axial measurement. The corresponding three-dimensional (3-D) volume was calculated by the integration of lesion areas in different images using volumetric software developed by engineers at National Central University, Taiwan. All data were analyzed separately for correlation with clinical staging, histological differentiation, pelvic lymph node metastasis and survival status. RESULTS: A statistically significant difference in tumor volume estimates was found between 3-D-integration and one-dimensional estimates among tumors with lymph nodes metastasis, cell differentiation and parametrial involvement. CONCLUSION: This study found that the parameters of lymph node metastasis, parametrial involvement and tumor differentiation are volume-dependent. 3D-tumor volumetry showed superior discrimination of these parameters compared to current single diameter evaluation suggesting its potential as a rapid method for initial prediction of prognostic factors in cervical cancer.

Adult↗
PubMed2002

Sialyltransferase family members and cervix squamous cell carcinoma.

Sialic acids including a number of their derivatives are ubiquitous at the terminal positions of the oligosaccharides of glycoproteins. The transfer of sialic acids from cystidine-5-monophospho-N-acetylneuraminic acid (CMP-NeuAc) to the terminal position of the carbohydrate group of glycoproteins and glycolipids is catalyzed by a family of sialyltransferases (STs). There is a large body of evidence to suggest that tumor cells have altered surface properties from their normal counterparts, and that these changes are partially due to altered sialo-glycoconjugates expressed on the plasma membrane and that altered sialylation (change in glycoprotein expression), which occurs during certain pathological processes, such as oncogenic transformation, tumor metastases, and invasion, is associated with enhanced ST activity. In this report we attempt to review the important findings in studing sialyltransferases of cervix squamous cell carcinoma.

Carcinoma, Squamous Cell↗
PubMed2001

Altered mRNA expression of sialyltransferase in squamous cell carcinomas of the cervix.

OBJECTIVE: Increased sialylation has been reported in various kinds of cancers, but to date, sialylation of cervical carcinoma has never been evaluated. This study of the changes in messenger ribonucleic acid (mRNA) expression of the four sialyltransferases (ST3Gal I, ST3Gal III, ST3Gal IV, and ST6Gal I) in a normal cervix and that with FIGO stage IB1 squamous cell carcinoma was undertaken to assess the extent of sialylation associated with establishment of the carcinoma. METHODS: Alterations in ST mRNA expression in FIGO IB1 cervical cancer (n = 30) and normal cervixes (n = 30) were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: ST6Gal I expression was enhanced in squamous cell carcinoma of the cervix (P = 0.026, Mann-Whitney U test), but mRNA expression from the other three STs (ST3Gal I, ST3Gal III, and ST3Gal IV) was significantly down-expressed in squamous cell carcinoma of the cervix compared to the normal cervix (P = 0.003, P < 0.001, and P = 0.001, respectively). High ST6Gal I expression was associated with more invasive properties of cervical cancer, such as deep stromal invasion, lymph or vascular space involvement, and poor differentiation (P = 0.010, P < 0.001, P < 0.001, respectively). CONCLUSIONS: A combination of enhanced ST6Gal I mRNA expression and decreased mRNA expression from ST3Gal I, ST3Gal III, and ST3Gal IV might be important in cervical cancer. Future studies will investigate whether RT-PCR detection of the expression of these enzymes can be helpful for prognostic purposes.

Carcinoma, Squamous Cell↗
PubMed2001

Diagnosis and localization of testosterone-producing ovarian tumors: imaging or biochemical evaluation.

OBJECTIVE: In the testosterone-secreting ovarian tumor (TSOT), the role of whole-body positron emission tomography (WBPET) with (fluorine-18)-2-deoxyglucose scanning (FDG) and/or [(11)C]acetate is unclear, although it presents a rationale that these functional tumors would be more active and have increased use of glucose and oxygen consumption than normal tissues. CASE: A 52-year-old woman had a history of steroid cell tumors of the right ovary (IIA) and she received staging surgery including total hysterectomy, salpingo-oophorectomy, and lymph node sampling. Reelevated serum levels of T (5.24 ng/ml) were noted 52 months later. The patient received serial preoperative examinations including WBPET with FDG and acetate, ultrasound, computerized tomography (CT), and magnetic resonance imaging (MRI) to evaluate her recurrence. A suspicious mass on the liver was found on ultrasound, CT, and MRI. The ultrasound-guided biopsy was performed three times, and each of them failed to provide any pathological confirmation. Functional imaging studies showed an abnormal uptake in WBPET using [(11)C]acetate but were negative using FDG. Because of the size of the tumor, the patient's hesitatancy toward an operation, and good previous response to gonadotropin-releasing hormone (GnRH) agonist treatment, the patient received a six-cycle GnRH agonist treatment. Serum T levels returned to normal limits after administration of the first dose of GnRH agonist. At follow-up, serum hormone levels were all within the normal ranges consistent with menopause, but the size of the metastatic tumor was constant. The tumor was then completely excised pathologically proven to be a metastatic TSOT. CONCLUSIONS: Recurrent TSOT might be successfully detected using WBPET with [(11)C]acetate. In addition, GnRH agonist could be tried in patients with TSOT if initial responses were excellent and surgical intervention could not be performed.

Carbon Radioisotopes↗
PubMed2001

Laparoscopic bipolar coagulation of uterine vessels: a new method for treating symptomatic fibroids.

OBJECTIVE: To evaluate the effects of laparoscopic bipolar coagulation of uterine vessels in treating symptomatic fibroids. DESIGN: Prospective clinical study. SETTING: University-affiliated tertiary referral center. PATIENT(S): Eighty-seven women with symptomatic fibroids warranting surgical treatment and wanting to retain their uteri. INTERVENTION(S): Laparoscopic bipolar coagulation of uterine arteries and anastomotic sites of uterine arteries with ovarian arteries. MAIN OUTCOME MEASURE(S): Percentage reduction in the dominant fibroid size and clinical response evaluation. RESULT(S): Eighty-five (97.7%) of 87 patients underwent technically successful laparoscopic coagulation of uterine vessels without intraoperative complications. The mean follow-up time was 10.2 months. Symptomatic improvement was reported in 76 (89.4%) of 85 patients, including 18 (21.2%) with complete resolution of symptoms. Significant reductions in the dominant fibroid size (average, 76%) and the uterine volume (average, 46%) were sonographically demonstrated. Two patients conceived 4 and 9 months, respectively, after treatment. Three (3.5%) premenopausal women became postmenopausal postoperatively. CONCLUSION(S): Laparoscopic bipolar coagulation of uterine vessels appears to be a promising new method for treating fibroid-related menorrhagia and pelvic pain.

Adult↗
PubMed2001

Successful treatment of symptomatic arteriovenous malformation of the uterus using laparoscopic bipolar coagulation of uterine vessels.

OBJECTIVE: To report a case of symptomatic arteriovenous malformation (AVM) of the uterus that was successfully treated with laparoscopic bipolar coagulation of uterine vessels. DESIGN: Case report. SETTING: University-affiliated tertiary referral center. PATIENT(S): A 66-year-old woman with symptomatic AVM of the uterus. INTERVENTION(S): Laparoscopic bipolar coagulation of uterine vessels. MAIN OUTCOME MEASURE(S): Clinical symptoms, color Doppler sonographic examination, and pelvic magnetic resonance imaging. RESULT(S): Remarkable shrinkage of the lesion size, obvious decrease in all of the impedance measurements (pulsatility, resistance, velocity indexes [systolic/diastolic]), and freedom from symptoms. CONCLUSION(S): This modality is a new alternative method for the management of patients with symptomatic AVM of the uterus who do not respond to conservative treatment.

Aged↗
PubMed2001

Intraperitoneal cisplatin-based chemotherapy vs. intravenous cisplatin-based chemotherapy for stage III optimally cytoreduced epithelial ovarian cancer.

OBJECTIVE: To compare the survival between intraperitoneal cisplatin-based chemotherapy (IPCT) and intravenous cisplatin-based chemotherapy (IVCT) in stage III epithelial ovarian cancer with minimal residual disease (<1 cm) after primary debulking surgery. METHOD: One hundred and thirty-two patients with stage III epithelial ovarian cancer after optimal primary debulking surgery with minimal residual disease between April 1990 and March 1995 were entered into a randomized clinical trial in which IPCT or IVCT was administered at 3-week intervals. Patients in the IPCT arm received cisplatin-based (100 mg/m(2)) intraperitoneal chemotherapy. Patients in the IVCT arm received cisplatin-based (50 mg/m(2)) intravenous chemotherapy. The tumor response was assessed every 3 months. The hematological toxicity using the South West Oncology Group (SWOG) toxicity criteria was assessed. Catheter complications associated with intraperitoneal chemotherapy were also analyzed. RESULT: The estimated median survival in the IPCT group was 43 months (95% confidence interval, 34-54) and IVCT group was 48 months (95% confidence interval, 37-59). The hazard ratio of death was not statistically significant between IPCT and IVCT (hazard ratio, 1.13; 95% CI, 0.69-1.86; P=0.317). The frequencies of hematological toxic effects were significantly lower in the IPCT group than in the IVCT group. CONCLUSION: Intravenous and intraperitoneal chemotherapy are associated with equivalent survival in patients with minimal residual stage III epithelial ovarian cancer after optimal cytoreductive surgery.

Adult↗