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Biomedical subjects

W F Cheng

Publications and source records attributed to W F Cheng.

At least 19 recordsLinked to original sources
PubMed1998

Clinical application of intratumoral blood flow study in patients with endometrial carcinoma.

BACKGROUND: The objective of this study was to evaluate the correlation between intratumoral blood flow as assessed by color Doppler ultrasound with stage, tumor grade, depth of invasion, and lymph node metastasis in endometrial carcinoma and determine its clinical usefulness. METHODS: Sixty-six patients with endometrial carcinoma were enrolled. All patients received surgical treatment. Transvaginal color Doppler ultrasound was performed before surgery to detect the arterial blood flow signals within the tumors and the lowest resistance index (RI) was recorded. Formalin fixed, paraffin embedded pathology slides were reviewed by a senior pathologist to evaluate the histologic grading, tumor size, depth of myometrial invasion, and presence of lymph node metastasis. RESULTS: Intratumoral RI correlated well with surgical staging, histologic grading, the depth of myometrial invasion, and the presence of lymph node metastasis. Significantly lower RI was noted in tumors of advanced stage (> than International Federation of Obstetrics and Gynecology [FIGO] Stage I) (0.38 +/- 0.09 vs. 0.54 +/- 0.11; P < 0.001), tumors with higher histologic grade (Grade 3) (0.36 +/- 0.08 vs. 0.53 +/- 0.11; P < 0.001), tumors with deep myometrial invasion (> 50% myometrial thickness) (0.38 +/- 0.07 vs. 0.54 +/- 0.11; P < 0.001), and tumors with lymph node metastasis (0.34 +/- 0.07 vs. 0.52 +/- 0.11; P < 0.001) compared with tumors with Stage I, Grade 1/2 histology, no or superficial myometrial invasion, and absence of lymph node metastasis, respectively. CONCLUSIONS: Intratumoral blood flow analysis assessed by color Doppler ultrasound correlates well with surgical stage, tumor grade, myometrial invasion, and lymph node metastasis in patients with endometrial carcinoma. Assessment of tumor angiogenesis using color Doppler ultrasound provides useful information for the preoperative prediction regarding stage, histologic grade, depth of myometrial invasion, and presence of lymph node metastasis in patients with endometrial carcinoma. The authors believe routine pelvic lymph node dissection should be performed for those patients whose lowest RI values of intratumoral blood flow are < or = 0.4 because those patients are at very high risk for pelvic lymph node involvement.

Adult↗
PubMed1997

Comparison of endometrial changes among symptomatic tamoxifen-treated and nontreated premenopausal and postmenopausal breast cancer patients.

Breast cancer patients who received tamoxifen as adjuvant therapy have been reported to have more endometrial lesions such as polyps, hyperplasia, or carcinoma. We conducted a prospective study to elucidate the endometrial changes of premenopausal and postmenopausal breast cancer patients with tamoxifen. Sixty-seven symptomatic breast cancer patients who had been on tamoxifen treatment, including 34 premenopausal and 33 postmenopausal patients, and another group of 48 patients who had not been on tamoxifen, including 25 premenopausal and 23 postmenopausal patients, were recruited. Symptomatic patients were defined as having hypermenorrhea or abnormal vaginal bleeding among premenopausal patients or postmenopausal bleeding among postmenopausal patients. Endometrial thickness and uterine size determined by vaginal ultrasonography, histologic findings, and risk factors for endometrial cancer were compared. The mean endometrial thickness and uterine size showed no statistically significant difference in premenopausal patients with (n = 34) or without (n = 25) tamoxifen treatment, whereas there was a significant difference in the postmenopausal patients with (n = 33) or without (n = 23) tamoxifen treatment (12.11 +/- 12.38 mm vs 5.41 +/- 2.70 mm, P = 0.025; 234.71 +/- 76.36 cm3 vs 108.81 +/- 81.27 cm3, P = 0.0018, respectively). The frequency of endometrial histopathologic findings was 23.5% (8/34) in tamoxifen-treated women compared with 12.0% (3/25) in nontreated women (P = 0.269) in the premenopausal groups. In contrast, it was remarkably high with 66.7% (22/33) in tamoxifen-treated women compared with 30.4% (7/23) in the nontreated women in the postmenopausal groups (P = 0.025). There were four postmenopausal patients with tamoxifen, including three with atypical endometrial hyperplasia and one endometrial carcinoma, in contrast to no postmenopausal nontreated patients, although this difference did not reach statistical significance in this study (P = 0.096). There was a remarkably high prevalence of endometrial histopathologic findings in symptomatic tamoxifen-treated breast cancer patients, especially postmenopausal women. Tamoxifen might be associated with premalignant or malignant changes in postmenopausal endometrium. Thus timely, aggressive histologic assessment such as curettage or hysteroscope should be performed to detect the endometrial lesions when symptoms occur. Vaginal ultrasonography could be a useful tool to detect the endometrial lesions.

Aged↗
PubMed1997

Evaluation of recombinant chitinase and SXP1 antigens as antimicrofilarial vaccines.

Prior studies indicate that a microfilarial stage-specific chitinase is a possible candidate antigen for a transmission-blocking vaccine against Brugian filariasis. The antigen is a functional enzyme that progressively appears as microfilariae mature and become able to infect and develop in a susceptible mosquito vector. It is recognized by a monoclonal antibody that reduces microfilaremia in infected animals and by a subset of sera from infected persons who remain amicrofilaremic. Immunization of jirds with recombinant chitinase induced partial protection against microfilaremia resulting from subsequent infection with Brugia malayi, but did not reduce adult worm burdens. Vaccination was much less effective when administered during the prepatent stage of infection and was ineffective when given to microfilaremic jirds. The protective epitope appears to be located close to the carboxy terminus of the chitinase molecule. Immunization of jirds with SXP1, an antigen present in multiple worm stages, also reduced microfilaremia and, in some experiments, adult worm burdens, but hyperimmunization with a recombinant filarial myosin was not protective. These observations indicate that the relative timing of immunization and infection is an important factor in the efficacy of antimicrofilarial vaccines.

Animals↗
PubMed1996

Prediction of residual neoplasia based on histopathology and margin status of conization specimens.

OBJECTIVE: To evaluate the status of cone margins and the severity of cervical neoplasia as predictors of residual lesions in the remaining cervices. METHODS: We performed a 7-year retrospective study and reviewed 172 patients who had undergone cervical conization followed by subsequent hysterectomy. Pathological findings of the cone margins and residual lesions in the postcone hysterectomy specimens were recorded for analysis. RESULTS: The prevalence rates of positive cone margins were 0, 18.6, 23.8, and 25%, respectively, in patients with low-grade squamous intraepithelial lesion (SIL) (n = 6), high-grade SIL (n = 129), stage IA1 cervical cancer (CC-IA1) (n = 21), and CC-IA2 (n = 16). The prevalence rates of positive residual lesions in postcone hysterectomy specimens were 0, 23.3, 23.8, and 43.8%, respectively, in those with low-grade SIL, high-grade SIL, CC-IA1, and CC-IA2. Residual lesions were significantly more frequently found in patients with positive cone margins (84.8%) than in those with negative margins (10.1%) (X2 = 76.81, P < 0.0001). All six patients with low-grade SIL had free cone margins. Positive predictive values of margin status for the presence of residual lesions were 83.3, 80, and 100%, respectively, in patients with high-grade SIL, CC-IA1, and CC-IA2. Only two (6.1%) of 33 patients with positive cone margins had more advanced residual lesions. Negative predictive values of margin status for the absence of residual lesions were 100, 90.5, 93.8, and 75%, respectively, in patients with low-grade SIL, high-grade SIL, CC-IA1, and CC-IA2. None of the 139 patients with negative margins had invasive residual lesion. CONCLUSIONS: (1) The prevalence of positive cone margin and residual lesion increased with higher severity of cervical neoplasia. (2) Patients with positive cone margins had significantly higher chances of having residual lesion than those with negative margins. (3) Free cone margin does not ensure the absence of residual lesion in the remaining cervix. However, the possibility of residual invasive cancer in the remaining cervix is remote. (4) Positive cone margin does not invariably indicate the presence and persistence of more severe residual lesion. Subsequent hysterectomy may be reserved for the patient with invasive cone pathology, the patient with concomitant morbid uterine condition, or the patient who is not reliable for continuous follow-up.

Conization↗
PubMed1996

Risk factors for recurrence in patients with stage IB, IIA, and IIB cervical carcinoma after radical hysterectomy and postoperative pelvic irradiation.

OBJECTIVE: To identify risk factors for cancer recurrence in patients with stage IB, IIA, and IIB cervical carcinoma after abdominal radical hysterectomy with pelvic lymph node dissection and postoperative pelvic irradiation. METHODS: One hundred and eighty-seven patients with cervical carcinoma stage IB (n = 63), IIA (n = 43), and IIB (n = 81) disease who received abdominal radical hysterectomy with pelvic lymph node dissection and postoperative pelvic irradiation were followed-up for 2-10 years. The histologic type, grade, lymphovascular tumor emboli, tumor size, invasion sites, deep cervical stromal invasion, and pelvic lymph node metastases were assessed for correlation with cancer recurrence. RESULTS: Recurrence occurred in 45 cases (24%), of whom 40 had died of the disease at the 5-year follow-up period. Univariate proportional hazards analysis revealed that the significant risk factors were adenocarcinoma, bulky tumor size (4 cm or greater), lymphovascular tumor emboli, deep cervical stromal invasion, and lymph node metastases, especially iliac nodal metastases and bilateral nodal metastases. Multivariate proportional hazards analysis showed that bulky tumor size (hazard ratio 2.34), tumor emboli (hazard ratio 2.74) and iliac nodal metastases (hazard ratio 5.31) remained significant risk factors. In contrast, no deaths occurred in the other 142 cases who did not have recurrence. CONCLUSION: This retrospective study suggests that stage IB, IIA, and IIB cervical carcinoma cases with the above-mentioned pathologic factors are at higher risk of recurrence after abdominal radical hysterectomy with pelvic lymph node dissection and postoperative pelvic irradiation.

Combined Modality Therapy↗
PubMed1996

Sonographic characteristics of adenofibroma of the endometrium following tamoxifen therapy for breast cancer: two case reports.

Adenofibroma of the endometrium is thought to be a rare benign variant of the mixed mesodermal tumor, and its preoperative diagnosis is difficult. We describe the sonographic characteristics of two cases of adenofibroma of the endometrium. In both cases the patient was receiving prolonged tamoxifen therapy following surgery for breast cancer. Sonographically, this rare disease is observed as an intracavitary mass containing multiple small cysts with low-resistance intratumor blood flow. The unique sonographic findings make the preoperative diagnosis possible.

Adenofibroma↗
PubMed1996

Endometrial stromal sarcoma of twenty cases.

BACKGROUND: Endometrial stromal sarcoma is a rare neoplasm. We reviewed twenty cases to study the characteristics of this disease. METHODS: Twenty cases of endometrial stromal sarcoma were treated at our hospital. The clinical stage, treatment and outcome were retrospectively analyzed. RESULTS: Endometrial stromal sarcoma comprised 4.3% of corpus cancers and 46.4% of uterine sarcomas at our hospital. Seven cases were stage I, one was stage II, ten were stage III, and two were stage IV at the time of diagnosis. Histopathologically, seventeen cases were classified as low-grade sarcoma and three were high-grade sarcoma. Seven patients had recurrence and five of them had already died of disease. Among these recurrent patients, one was stage II and six were stage III. All three patients with high-grade sarcoma and four with low-grade sarcoma had recurrence. CONCLUSIONS: We think mitotic count is an important prognostic factor in low-grade endometrial stromal sarcoma and high-grade endometrial stromal sarcoma has a poor prognosis even with post-operative adjuvant treatment.

Adjuvants, Pharmaceutic↗
PubMed1996

Scalene lymph node metastases with the negative pelvic nodes in invasive cervical carcinoma.

Cervical carcinoma spreads predominantly by lymphatic routes and lymph node metastases may occur even in early stages of disease. Metastases usually first appear in pelvic lymph nodes, then disseminate along the efferent lymphatic chain to the extrapelvic lymph nodes. Cases of positive lymph node metastases with negative pelvic nodes in invasive cervical carcinoma are extremely rare. We report a 50-year-old woman with bulky stage IIA cervical carcinoma who had scalene lymph node metastases in the absence of pelvic lymph node metastases after radical hysterectomy and postoperative pelvic irradiation. This rare "skipping" nodal metastasis was probably via posterior trunk lymphatic drainage of the bulky cervical carcinoma which mainly invaded the posterior vaginal cuff. Neoadjuvant or adjuvant chemotherapy is recommended to prolong survival of patients in such cases.

Carcinoma, Squamous Cell↗
PubMed1996

Triplet pregnancy complicated by intrauterine fetal death of conjoined twins from an umbilical cord accident of an acardius. A case report.

BACKGROUND: Acardius is a rare occurrence in monozygotic multiple pregnancies. Triplet pregnancy composed of an acardiac fetus and a pair of conjoined twins is even more rare. The outcome of the acardius is invariably fatal, and the mortality rate of the other fetuses ranges between 50% and 70%. Perinatal mortality results mainly from complications of twin-twin transfusion syndrome. CASE: Intrauterine fetal death, caused by an umbilical cord accident, with twisting of the acardius's cord around the fused cords of conjoined twins is reported in this present work. CONCLUSION: An acardius should be thoroughly sought when monochorionic multiple pregnancies are found by ultrasound during prenatal care. The complications of pregnancy caused by an acardiac fetus can be avoided by using proper management.

Adult↗
PubMed1995

Prenatal diagnosis of 46,XX/47,XXY mosaicism: a case report.

A case of 46,XX/47,XXY mosaicism was diagnosed at 22 gestational weeks by amniocentesis and fetal blood sampling. After genetic counselling, the couple elected to have the pregnancy terminated. Culture of the fetal skin and both gonads confirmed the prenatal diagnosis. In external appearance, the abortus had no remarkable findings except hypospadia. Histology of both gonads showed testicular tissue without evidence of ovarian components.

Abortion, Induced↗
PubMed1995

Leiomyosarcoma of the broad ligament: a case report and literature review.

Solitary tumors of the broad ligament are rare. The most frequent solid tumor of the broad ligament is leiomyoma. Leiomyosarcoma of the broad ligament (LBL) is an extremely rare malignant tumor. Nine cases of leiomyosarcoma of the broad ligament had been reported previously. A 59-year-old woman with LBL is reported. Treatment consisted of resection and total abdominal hysterectomy with bilateral salpingo-oophorectomy. No evidence of metastasis is noted after 12 months follow-up. We conclude that the management of LBL is excision of the leiomyosarcoma as completely as possible and postoperative adjuvant chemotherapy.

Broad Ligament↗
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↗
PubMed1994

Abdominal pregnancy after gonadotropin superovulation and intrauterine insemination: a case report.

An abdominal pregnancy after superovulation with human menopausal and chorionic gonadotropins followed by intrauterine insemination of the husband's sperm is reported. The incidence of ectopic pregnancy increases with administration of human menopausal and chorionic gonadotropins. However, the role of human menopausal and chorionic gonadotropins as a cause of abdominal pregnancy has not been delineated. It appears that ultrasonography has become one of the most important aids in the diagnosis of early abdominal pregnancy.

Abdomen↗
PubMed1993

[Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine: immunological observation].

We compared the effect of a single dose of ivermectin (100 micrograms/kg) with that of a standard course of diethylcarbamazine (DEC) (6 mg/kg) on several parameters of the host's antifilarial immune response in 60 patients with bancroftian filariasis enrolled in a double-blind drug trial. All participants had measurable serum levels of antifilarial antibodies and parasite antigens. Drug-induced clearance of microfilaremia was associated with a temporary increase in HC11 antigenemia and a decrease in serum levels of antibodies to soluble filarial antigens. Antigenemia progressively declined in patients who remained a microfilaremic after treatment, but declined and then rose in persons with recurrent microfilaremia. Treatment triggered a sustained increase in serum levels of IL-1, IL-6, TNF alpha and IFN gamma in all patients. Although Ivermectin and DEC are believed to exert their antiparasite activity via different mechanisms, the same pattern of serological changes was observed in patients treated with either drug.

Animals↗
PubMed1992

[Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. I. Clinical and parasitological observations].

We compared the efficacy of a single dose of ivermectin with that of a standard course of deithylcarbamazine (DEC) for the control of microfilaremia in 60 patients with banrroftian filariasis who had developed recurrent microfilaremia after each of three or more prior treatments with DEC. The study was done as a randomized, double-blind trial. Complete, but transient clearance of microfilaremia was observed in both treatment groups. One year later, recurrent microfilaremia was present in 7 patients treated with ivermectin and in 5 treated with DEC. Pretreatment levels of microfilaremia were significantly higher in patients who relapsed within one year after treatment than in those who remained amicrofilaremia. Side effects of either treatment were common but mild. Febrile reactions were more frequent in the ivermectin group: while localized reactions consistent with a flare up of acute filarial disease occurred mostly in the DEC group. We conclude that ivermectin is an effective and practical alternative to DEC for treatment of recurrent microfilaremia due to bancroftian filariasis.

Adolescent↗
PubMed1991

An approach to establishing N-nitroso compounds as the cause of gastric cancer.

Although gastric cancer is the most common cause of mortality from cancer, its etiology is not yet clear. To elucidate the role of N-nitroso compounds, we investigated 30 cases of gastric cancer by determination of the contents of nitrate and ascorbic acid and by detection of mutagens in urine. Cases were paired 1:1 with patients with dysplasia and normal controls of the same sex and age group. In comparison with normal controls, the gastric cancer group had higher nitrate and lower ascorbic acid levels in urine. Mutagenicity was observed in the urines of 83.3% of the gastric cancer cases and in 16.6% of the dysplasia group, but in none of those from normal controls. When the N-nitroso compound content of gastric juice was determined, the levels in control subjects were significantly lower than those in persons with gastric cancer. These results support the hypothesis that the cause of gastric cancer may be N-nitroso compounds.

Ascorbic Acid↗
PubMed1991

Efficacy of ivermectin for control of microfilaremia recurring after treatment with diethylcarbamazine. I. Clinical and parasitologic observations.

We compared the efficacy of a single dose of ivermectin with that of a standard course of diethylcarbamazine (DEC) for the control of microfilaremia in 60 patients with bancroftian filariasis who had developed recurrent microfilaremia after each of three or more prior treatments with DEC. The study was done as a randomized, double-blind trial. Complete, but in some cases, transient clearance of microfilaremia was observed in both treatment groups. At one year, recurrent microfilaremia was present in seven patients treated with ivermectin and in five treated with DEC. Pretreatment levels of microfilaremia were significantly higher in patients who relapsed within one year after treatment than in those who remained amicrofilaremic. Side effects with both treatments were common, but mild. Febrile reactions were more frequent in the ivermectin group; localized reactions consistent with a flare-up of acute filarial disease occurred mostly in the DEC group. We conclude that ivermectin is an effective and practical alternative to DEC for treatment of recurrent microfilaremia due to bancroftian filariasis.

Adolescent↗