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S N Chow

Publications and source records attributed to S N Chow.

At least 37 records · Page 2Linked to original sources
PubMed1997

Light-induced fluorescence spectroscopy to differentiate benign and malignant uterine cervical lesions.

In Taiwan, cervical cancer is the leading malignancy among women. For the early detection of cervical neoplasia, light-induced fluorescence spectroscopy was conducted ex vivo to assess the ability of this technique to differentiate cervical neoplastic tissue (20 samples) from normal or inflammatory cervical tissue (37 samples) at an excitation wavelength of 280 nm. The principal fluorescent peaks occurred within +/- 5 nm of 330 nm and 470 nm emission. At 330 nm emission, the spectrum of the normal or inflammatory tissue was significantly stronger than that of the neoplastic tissue after are normalization. However, at 470 nm emission, the spectrum of the normal or inflammatory tissue was significantly weaker than that of the neoplastic tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the 5 +/- nm peak area of each sample was calculated and paired. The ratios showed that histologically neoplastic lesions could be distinguished from inflammatory samples using a 280-nm-excitation wavelength with a sensitivity, specificity and positive predictive value of 94%, 82% and 73%, respectively. The average ratio of malignant or dysplastic cervical samples was significantly greater than that of the inflammatory samples (p < 0.001). Our ex vivo study indicated that light-induced fluorescence spectroscopy may be useful in differentiating malignant or premalignant from normal or inflammatory cervical tissue.

Algorithms↗
PubMed1997

Demographic characteristics and medical aspects of menopausal women in Taiwan.

This report describes the medical and demographic characteristics of menopausal women in Taiwan in order to provide information for consideration during future healthcare planning. The medical and demographic data analyzed were taken from officially published materials of the Government of the Republic of China on Taiwan, our own studies, and those of other researchers. In 1994, the average lifespan of men in Taiwan was 71.8 years and that of women was 77.7 years. The age of menarche was 13.6 years and the age of menopause was 49.5 years. Women aged 50 and over accounted for 18.3% of the total female population and 8.9% of the total population in Taiwan. In 1994, 68.9% of women in Taiwan aged 50 and over were married. The most frequently occurring menopausal symptoms in Taiwanese women were lumbago or low backpain (68%), fatigue (59%), impairment of memory (55%), vaginal dryness (50%), and hot flushes and sweating (49%). The spinal bone mineral density of women decreased markedly after the age of 50 years. The prevalence of vertebral fracture in women 65 years and over was 19.8%, which was higher than the 12.5% in men of the same age group. The prevalence of hypertension and coronary heart disease in women 50 years or older was also higher than in men. The most frequent sites of cancer in women in 1992 were the cervix uteri, breast, sigmoid colon and rectum, lungs, liver, stomach, thyroid, ovaries, hemopoietic and reticuloendothelial systems, and skin. There were 14,298 newly reported cases of malignant neoplasms in women in 1992. About 60% of these occurred in women aged 50 years or more. The median age of occurrence of cervix uteri, breast, and ovarian cancers was 48 to 49 years, which is very close to the menopause age. About 30% of menopausal women in Taiwan are currently living without a husband. Although 18.3% of women in Taiwan were at least 50 years old, approximately 60% of all malignant neoplasms in the female population occurred in this group. There is an urgent need for menopausal women in Taiwan to receive psychologic support and comprehensive medical care.

Adult↗
PubMed1996

Malignant ovarian germ cell tumors.

OBJECTIVES: Fifty patients with malignant ovarian germ cell tumors, which accounts for 10.8% of all ovarian malignancies, were treated from 1977 through 1994. Their cases are reviewed. METHODS: The histology includes endodermal sinus tumor (EST) in 15 patients, immature teratoma in 14, dysgerminoma in 13, and mixed germ cell tumor in eight. The mean age at presentation was 21.5 years and mean primary tumor diameter was 16 cm. All patients underwent surgery as the initial treatment, and 10 received more than one operation. Postoperative adjuvant chemotherapy was not given to cases with stage Ia immature teratoma and dysgerminoma. VAC (vincristine, actinomycin D, cyclophosphamide) and BVP (bleomycin, vinblastine, cisplatin) regimens were utilized in early 1980s for EST and advanced-stage tumors of immature teratoma and dysgerminoma. BEP (bleomycin, etoposide, cisplatin) and EP (etoposide, cisplatin) regimens were applied in advanced-stage disease and some stage I disease since 1990. VIP (VP-16, ifosfamide, cisplatin) regimen was employed as salvage regimen in cases where other combinations failed. RESULTS: alpha-Fetoprotein (AFP) was elevated in every tumor containing endodermal sinus element, and AFP served as a good indicator for prediction of tumor recurrence. The follow-up time ranged from 5 to 144 months with the mean of 54.5 months. CONCLUSIONS: The survival rate for EST was 54%, that for immature teratoma and dysgerminoma was 85% and 90%, respectively.

Adolescent↗
PubMed1996

Borderline malignant tumors of the ovary: study of prognostic factors.

A 16-year review of borderline tumors of the ovary was carried out to study the clinical features and outcomes of patients and to assess the value of color Doppler ultrasound in preoperative diagnosis. The records of 53 patients with borderline tumors of the ovary were retrospectively analyzed for clinical features, sonographic findings and survival. Twenty-three of 44 patients with stage I disease were treated conservatively without recurrence. Seven of eight (87.5%) patients with stage III disease developed recurrent or persistent tumors within 3 years. Overall, eight of 53 (15.1%) patients had recurrent or persistent disease. Twenty-three of 44 (52.3%) patients with borderline ovarian tumors showed morphologic malignancy by gray-scale sonography. Ten of 13 (76.9%) patients who had color Doppler ultrasound examination had detectable intratumoral blood flow. The mean resistance index value was 0.47 (range, 0.3-0.6). Three of these patients (30%) had a resistance index value < 0.4. The results indicated that the extent of disease as reflected by the clinical stage was the main factor for prediction of recurrence, and borderline tumors of the ovary were not efficiently differentiated from benign or malignant tumors by resistance index values obtained from color Doppler ultrasound.

Adolescent↗
PubMed1996

The suitable treatment for adenocarcinoma in situ of uterine cervix: a report of four cases.

Adenocarcinoma in situ (AIS) of the uterine cervix is a rare disease. Some authors suggested that conization is a suitable treatment for AIS as for squamous cell carcinoma in situ. However, others did not agree. Four cases of AIS, from 1984 to 1994, have been diagnosed in the Hospital of National Taiwan University. If the diagnosis of the conization specimen showed AIS, abdominal total hysterectomy was performed days thereafter. The remaining uterine cervix was checked by histopathology to determine whether it was free of cancer lesions. AIS lesions remained in the uterine cervix, as shown by conization in two cases. AIS is not like lesion as squamous cell carcinoma in situ lesion which is easy to be removed by conization. It is suggested that conization is not an adequate treatment for AIS, rather, a total hysterectomy should be performed.

Adenocarcinoma↗
PubMed1996

Light-induced fluorescence spectroscopy: a potential diagnostic tool for oral neoplasia.

For the early detection of oral neoplasia, light-induced fluorescence spectroscopy was used to measure the fluorescence emission of malignant (squamous cell carcinoma & verrucous carcinoma) and premalignant (epithelial dysplasia, hyperkeratosis & lichen planus) oral tissues as well as normal oral mucosa ex vivo to assess the ability of this technique to distinguish neoplastic from normal oral tissues. The emission spectra of histologically normal and neoplastic oral tissues were obtained under excitation wavelengths varied from 270 nm to 400 nm at 10-nm intervals. At 300-nm excitation, the most intensely fluorescent peak occurred at 330-nm and 470 nm emission. At 330-nm emission, the spectrum of the malignant oral tissue was significantly stronger than that of the normal oral mucosal tissue after area normalization. However, at 470-nm emission, the spectrum of the malignant oral tissue was significantly weaker than that of the normal oral mucosal tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the +/-5 nm peak area of each sample was calculated and paired. The histogram of ratios showed that histologically neoplastic oral tissues could be distinguished from normal oral mucosal tissues using the 300 nm excitation wavelength. The average ratio of malignant or premalignant oral samples was significantly greater than that of the normal oral mucosal samples (p < 0.001). This ex vivo study indicated that fluorescence spectroscopy may be useful in differentiating malignant or premalignant oral tissue from normal oral mucosa.

Areca↗
PubMed1995

Independent clinical factors which correlate with failures in diagnosing early cervical cancer.

Our aim was to identify independent factors that correlated with colposcopically directed biopsy's reliability as a method for diagnosing early cervical cancer. One hundred ninety-one of a total of 2265 patients who had colposcopic examinations because of abnormal Papanicolaou smears were included in this study. These patients had all undergone a hysterectomy after being diagnosed as having cervical intraepithelial neoplasia grade III by colposcopically directed biopsy. By univariate analysis, old age (P = 0.0195), achievement of menopausal status (P = 0.0046), large lesion size (P = 0.0021), and unsatisfactory colposcopy (P = 0.0017) were found to be associated with the nondiagnosis of early cervical cancer. However, multivariate analysis using stepwise logistic regression revealed that large lesion size (P = 0.003) and unsatisfactory colposcopy (P = 0.0008) were the only independent factors that correlated with nondiagnosis. Our findings indicate that in order to reach a clear-cut diagnosis, cases with either unsatisfactory colposcopy or satisfactory colposcopy with large lesions (despite a lack of histologic evidence of invasions) should undergo a diagnostic conization.

Adult↗
PubMed1995

Is total abdominal hysterectomy with bilateral salpingo-oophorectomy adequate for new FIGO stage I endometrial carcinoma?

OBJECTIVE: The new FIGO staging for endometrial cancer cases complies with other forms of surgical staging and correlates better with clinical outcomes because it includes prognostic factors. This study was done to investigate whether total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH+BSO) is adequate for new FIGO Stage I endometrial carcinoma. SUBJECTS: Sixty-five cases of endometrial carcinoma defined according to the new FIGO Stage Ia (n = 26), Ib (n = 24) and Ic (n = 15) were analysed. They all received TAH+BSO only and were followed up for at least two years. METHODS: The histologic type, grade, depth of myometrial invasion, lympho-vascular tumour emboli and tumour size were analysed by t-test to correlate the risk factors for treatment failure. RESULTS: There were no recurrences after TAH+BSO in Ia and Ib cases. However, recurrences occurred in five cases (33%) of Stage Ic with deep myometrial invasion, high histologic grade, large tumour size and tumour emboli. CONCLUSIONS: TAH+BSO is inadequate in some Ic cases with a high histologic grade, deep myometrial invasion and tumour emboli. Thus, thorough pre-operative and intra-operative staging, adequate operation method and prompt post-operative adjuvant therapy are indispensable for successful treatment.

Adult↗
PubMed1995

Immunoelectrophoretic differentiation of alpha-fetoprotein in disorders with elevated serum alpha-fetoprotein levels or during pregnancy.

Our study aims to make differential diagnosis by immunoelectrophoresis for some common conditions with elevated levels of serum alpha-fetoprotein (AFP). One hundred and nine cases with elevated AFP levels were included in this study: yolk sac tumor (n = 8), hepatocellular carcinoma (n = 26), gastric cancer (n = 12), chronic hepatitis (n = 27) and normal pregnancy (n = 36). Lectin agarose gel electrophoresis, antibody-affinity blotting, and immunoreaction were used to identify the specific patterns of AFP in the respective conditions. The results showed that there were three possible bands: L1, L2 and L3. Yolk sac tumor produced a prominent L2 band and a light L3 band. Hepatocellular carcinoma produced a prominent L1 band and a light L3 band. Gastric cancer produced only an L1 band. Chronic hepatitis had a light L1 band and a pronounced L3 band. In pregnancy, the AFP pattern is similar to that of hepatocellular carcinoma. Immunoelectrophoresis is a useful method facilitating the differentiation of AFP origins.

Biomarkers, Tumor↗
PubMed1995

Torsion of an ovarian borderline tumor with extreme serum tumor markers: a case report.

A postmenopausal woman with torsion of the left ovarian mucinous cystadenoma with borderline malignancy is reported. Extremely elevated serum tumor markers such as carcinoembryonic antigen (CEA) (398.0 ng/mL, normal < 3.0 ng/mL), carbohydrate antigen 19-9 (CA 19-9) (240 U/mL, normal < 37 U/mL) and tissue polypeptide antigen (TPA) (1,918 U/L, normal < 110 U/L) were found preoperatively. Imaging studies such as ultrasound and computed tomogram favored a diagnosis of ovarian malignancy, and advanced ovarian cancer was suspected prior to operation. Diagnosis of borderline malignancy was first made by frozen section during laparotomy. The patient recovered following simple total hysterectomy and bilateral salpingo-oophorectomy. Serum levels of the tumor markers became normal gradually following operation. To present knowledge, this is the first reported case with extremely high serum tumor markers in a postmenopausal woman with torsion of a stage-Ia ovarian mucinous cystadenoma of borderline malignancy. Rapid release of these tumor markers into circulation secondary to necrosis and degeneration of the tumor cells following torsion might account for such an unusual finding.

Aged↗
PubMed1995

Female genital tuberculosis: report of seven cases.

Seven cases of histologically proven genital tuberculosis (TB) encountered at the National Taiwan University Hospital in the past 16 years were reviewed. From a total of 54,576 gynecologic specimens submitted for pathologic examination, the occurrence of genital TB was 0.01%. Of these seven patients, one suffered from primary infertility and one from secondary infertility. The patient with primary infertility had been married for 29 years. The patient with secondary infertility underwent a tuboplasty due to bilateral hydrosalpinx. Genital TB was not diagnosed preoperatively in any of the seven cases. The preoperative diagnoses included: postmenopausal spotting, ovarian malignancy, cervicitis, ectopic pregnancy and hydrosalpinx with secondary infertility. This review suggests that genital TB is becoming rare in Taiwan. It is difficult to diagnose from clinical symptoms and is usually discovered on pathologic examination.

Adult↗
PubMed1994

Oxidation of LDL by nitric oxide and its modification by superoxides in macrophage and cell-free systems.

Oxidative modification of low density lipoproteins (LDL) can increase the atherogenicity of LDL. Here we demonstrate the potential role of nitric oxide (NO) in LDL modification. Dose-dependent alterations of LDL including an increase in electrophoretic mobility, generation of peroxides and degradation of apoprotein B occurred during incubation with NO. Sodium nitroprusside was also shown to increase the electromobility of LDL. Superoxide dismutase (SOD) and catalase did not affect this result. NO treatment also increases the negative charges on other lipoproteins. In addition, we have demonstrated that NO plays a protective role in macrophage or superoxide-induced LDL modification through its neutralizing action.

Animals↗
PubMed1994

Malignant fibrous histiocytoma of the broad ligament.

Malignant fibrous histiocytoma of the broad ligament origin is extremely rare. We report a case of a 64-year-old female with a broad ligament tumor mass, who underwent complete excision of the mass, total hysterectomy, and bilateral salpingo-oophorectomy. Pathology showed a malignant fibrous histiocytoma of the broad ligament. The postoperative course was uneventful and no radiation or chemotherapy was given. She has been carefully monitored for 16 months and is without recurrence.

Broad Ligament↗
PubMed1994

Alpha-fetoprotein in women during pregnancy and in the neonate during intrapartum.

To evaluate alpha-fetoprotein (AFP) levels in women during pregnancy and in the neonate, 256 singleton pregnancies without medical, gynecologic, obstetric, or neonatal complications were studied. Sera for measuring maternal AFP (MAFP) levels were taken in midtrimester (16 to 18 weeks), third trimester (32 to 34 weeks), and during intrapartum (38 to 41 weeks). For measuring umbilical arterial AFP (UAAFP) and umbilical venous AFP (UVAFP) levels, sera of newborn were taken from the umbilical cord at delivery. AFP levels were measured by radioimmunoassay. Our results show that the MAFP levels at third trimester were higher than during intrapartum or midtrimester. Birthweights correlated well with MAFP levels in midtrimester. However, they did not significantly correlate with the MAFP levels at third trimester or intrapartum, nor with UAAFP or UVAFP levels. UAAFP levels were not significantly different from UVAFP levels. Intrapartum MAFP correlated well with UAAFP but not with UVAFP, birthweight, or parity. The concentration gradient between fetal and maternal serum during intrapartum is approximately 750:1. We conclude that MAFP levels in midtrimester can reflect birthweight. The data of normal AFP gradient may also be useful for diagnosing intrapartum fetomaternal hemorrhage.

Analysis of Variance↗
PubMed1994

Persistent gestational trophoblastic tumour with partial hydatidiform mole as the antecedent pregnancy.

OBJECTIVE: A 16 year review of persistent gestational trophoblastic tumour when the antecedent pregnancy was a partial hydatidiform mole. DESIGN: Cases of persistent gestational trophoblastic tumour with partial hydatidiform mole as the antecedent pregnancy were reviewed for the period 1976 to 1992. DNA ploidy was analysed by flow cytometry. SETTING: A University Hospital which is a reference centre for gestational trophoblastic tumour. SUBJECTS: The case notes of 207 women with persistent gestational trophoblastic tumour were reviewed. MAIN OUTCOME MEASURES: A rise (or failure to fall) of beta hCG titre, or sign of metastasis. RESULTS: Six (2.9%) women had partial hydatidiform mole as the antecedent pregnancy and all were initially judged to be low risk. However, two developed pulmonary metastasis; one woman developed persistent gestational trophoblastic tumour shortly after a hysterotomy, and none developed choriocarcinoma. The geometric mean of serum beta hCG concentrations at the initiation of chemotherapy was 868 mIU/ml (95% CI 114-1524). Of the six women, one achieved remission after total abdominal hysterectomy, and five after chemotherapy. The mean interval from starting treatment to remission was 68 days (95% CI 27.9-108.0). The initial beta hCG titre and interval were not statistically different from those found in cases of persistent gestational trophoblastic tumour when the antecedent pregnancy was not partial hydatidiform mole. Of the six, the DNA content was triploid in three and diploid in two. One of the two diploid cases required multiple courses of chemotherapy to achieve remission. CONCLUSION: Partial hydatidiform mole can have malignant sequelae and can develop very soon after treatment. Its DNA content can be either diploid or triploid, the lungs being the most common site of metastasis. After evacuation of partial hydatidiform mole, immediate chest X-ray and regular follow up of the serum beta hCG level is necessary.

Adult↗