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Biomedical subjects

F F Liu

Publications and source records attributed to F F Liu.

At least 37 records · Page 2Linked to original sources
PubMed1998

T1/T2 glottic cancer managed by external beam radiotherapy: the influence of pretreatment hemoglobin on local control.

PURPOSE: Pretreatment hemoglobin (Hb) level has been reported to be an important prognostic factor for local control and survival in various malignancies. However, in many settings, the adverse effect of a low Hb may be related to more advanced disease. The purpose of this analysis was to assess the influence of pretreatment Hb on local control in a large series of patients with a localized cancer (T1/T2 glottic cancer, AJCC 1992) treated in a standard fashion. MATERIALS AND METHODS: Between January 1981 and December 1989, 735 patients (median age 63; 657 males, 78 females) with T1/T2 glottic cancer were treated with radiation therapy (RT). The standard RT prescription was 50 Gy in 20 fractions over 4 weeks (97% of patients). Factors studied for prognostic importance for local failure included pretreatment Hb, age, sex, T category, anterior commissure involvement, subglottic extension, and tumor bulk (presence of visible tumor vs. subclinical disease). RESULTS: With a median follow-up of 6.8 years (range 0.2-14.3), 131 patients have locally relapsed for an actuarial 5-year relapse-free rate of 81.7%. The 5-year actuarial survival was 75.8%. The mean pretreatment hemoglobin level was 14.8 g/dl and was similar in all prognostic categories. On multivariate analysis, using the Cox proportional hazards model, pretreatment Hb predicted for local failure after RT. The hazard ratio (HR) for relapse was calculated for various Hb levels. For example, the HR for a Hb of 12 g/dl vs. a Hb of 15 g/dl was 1.8 (95% confidence interval 1.2-2.5). Previously established factors, including gender, T category, subglottic extension, as well as tumor bulk, were also prognostically important for local control. CONCLUSIONS: This analysis, in a large number of similarly treated patients, indicates that pretreatment Hb is an independent prognostic factor for local control in patients with T1/T2 carcinoma of the glottis treated with RT. The underlying biology of this observation needs to be explored, and using this information, it may be possible to develop strategies to improve treatment outcome.

Carcinoma, Squamous Cell↗
PubMed1998

Outcome in breast cancer managed without an initial axillary lymph node dissection.

PURPOSE: The role of an elective axillary lymph node dissection (AxLND) in the initial management of patients with early stage breast cancer has recently become controversial. The objective of this current study is to review the reasons as to why patients from a single institution were managed without an initial AxLND and their outcome in terms of survival and recurrence rates. MATERIALS AND METHODS: A retrospective analysis was conducted on 126 women referred to the Princess Margaret Hospital with the diagnosis of breast cancer who did not undergo an initial AxLND. RESULTS: The median age of this population was 69 years, with the vast majority (93%) being post-menopausal. Fifty-seven patients had T1 tumors and the remainder had T2-3 tumors. Adjuvant radiation therapy to the breast was administered to 65 patients and systemic adjuvant treatment was administered to 24 patients. In approximately one-third of these cases, the reasons cited for not performing an AxLND were related to the patient's age, a medical contraindication, or the patient's choice. The 5-year actuarial cause-specific survival was 92%; the local breast relapse-free rate (RFR) was 85% and the axillary RFR was 86%. No patients in this study experienced debilitating symptoms from their axillary disease. Only 16 patients underwent a subsequent AxLND, with the lymph nodes being pathologically uninvolved in six of these patients. CONCLUSION: This study supports the concept that. in selected patients, adopting an approach of a delayed AxLND does not appear to compromise the patients' outcome, with only 13% of patients requiring a subsequent AxLND.

Actuarial Analysis↗
PubMed1998

Gestational breast cancer.

OBJECTIVE: To study the problems of breast imaging in gestational breast cancer. PATIENTS AND METHOD: Retrospective review of the charts of 19 patients with breast cancer detected during pregnancy or lactation or within 1 year of delivery, who were referred to a tertiary centre for adjuvant therapy between 1986 and 1996. For 10 patients who underwent breast imaging, mammograms and breast ultrasonograms or reports were requested from outside facilities. RESULTS: The patients ranged in age from 23 to 41 years (mean 31 years). All 19 patients presented with palpable tumours; in 7 patients, the tumours were stage T2 or higher; in 11 patients, the tumours were at an advanced stage with positive axillary nodes. In 11 of the patients there was a delay in diagnosis, which ranged from 2 to 16 months. Of the 8 mammograms that could be reviewed, 5 showed infiltrating ductal carcinomas with typical features, which were detected as a mass (in 1 case), a mass with microcalcifications (in 1 case), microcalcifications (in 2 cases) and asymmetry (in 1 case). Three mammograms were negative, including 1 obtained from a patient with extensive comedocarcinoma. Breast ultrasonograms obtained from 4 patients (2 of whom also had mammograms) showed solid hypoechoic masses; in 2 of the ultrasonograms, the masses simulated a benign lesion. CONCLUSIONS: Although breast cancer during pregnancy and lactation is rare, this study suggests that radiologists should include it in the differential diagnosis of a solid breast mass seen during pregnancy or lactation. Clinicians appear to be reluctant to use breast imaging in these patients; however, this can lead to a delay in diagnosis. Ultrasonography is the modality of choice for initial analysis of such a mass in this age group. Mammography with shielding of the abdomen is recommended if there is suspicion of cancer. Clinical, mammographic and sonographic findings should be integrated for optimum interpretation.

Adult↗
PubMed1997

Relationship between thermal dose and outcome in thermoradiotherapy treatments for superficial recurrences of breast cancer: data from a phase III trial.

PURPOSE: The objective of this study was to determine whether the thermal dose delivered during hyperthermia treatments and other thermal factors correlate with outcome after combined radiation and hyperthermia of breast carcinoma recurrences. Data were from the combined hyperthermia and radiation treatment arms of four Phase III trials, which when pooled together, demonstrated a positive effect of hyperthermia. METHODS AND MATERIALS: Four Phase III trials addressing the question of whether hyperthermia could improve the local response of superficial recurrent breast cancer to radiation therapy were combined into a single analysis. Thermal dosimetry data were collected from 120 of the 148 breast cancer recurrence patients who received hyperthermia. The data were analyzed for correlations between thermal parameters as well as important clinical parameters and outcome (complete response rate, local disease free survival, time to local failure, and overall survival). RESULTS: Five thermal parameters were tested, all associated with the low regions of the measured temperature distributions. Max(TDmin) and Sum(TDmin) were associated with complete response where TDmin is the minimum thermal dose measured by any of the tumor temperature sensors during a treatment: Max(TDmin) is the maximum of TDmin over a series of treatments. Using a categorical relationship with a cutoff of 10 min for Sum(TDmin), the complete response rate was 77% for Sum(TDmin) > 10 min and 43% for Sum(TDmin) < or = 10 min (p = 0.022, adjusted for study center and significant clinical factors). The overall complete response rate for hyperthermia and radiation was 61% compared to 41% for radiation alone. Either Max(TDmin) or Sum(TDmin) were also associated with local disease free survival, time to local failure and overall survival. CONCLUSIONS: An earlier report of this trial demonstrated a significant benefit when hyperthermia was added to radiation in the treatment of breast cancer recurrences. The analysis of thermal factors demonstrates that parameters representative of the low end of the measured temperature distributions are associated with initial complete response rate, local disease-free survival, time to local failure and overall survival.

Breast Neoplasms↗
PubMed1997

Prenatal diagnosis of cephalothoracopagus janiceps monosymmetros.

We report a case of cephalothoracopagus janiceps monosymmetros that was diagnosed prenatally by ultrasound at 23 weeks' gestation. Obstetric ultrasound demonstrated conjoined female twins with a single fused cranial vault irregular in contour, duplicated cerebra, one face, two eyeballs, a fused thorax, two hearts, two thoracic spines, eight limbs, and polyhydramnios. The pregnancy was terminated and all the features described prenatally were observed at necropsy. The asymmetrical fused faces consisted of a ventral humanoid face with micrognathia, microphthalmia, low-set ears, a normal nose, and an opposite reduced face with partial facial features of a central narrowed fissure and paired synotic ears. The conjoined twins had fused umbilical cords, omphalocoele, and a single oesophagus, stomach, and duodenum, but duplicated pancreases, spleens, and central nervous, cardiopulmonary, hepatic, and genito-urinary systems. The common gastrointestinal tract bifurcated at the level of the jejunum. Our case documents a very uncommon variety of asymmetrical cephalothoracopagus janiceps with duplicated central nervous systems.

Adult↗
PubMed1997

Skeletal deformities of acardius anceps: the gross and imaging features.

A morphology based imaging review is presented of the characteristic skeletal deformities associated with acardius anceps in three acardiac twins. These fetuses demonstrated poorly developed skulls, limb reduction defects, and phocomelia of the upper limbs, as well as narrow thoracic cages with or without the complete development of ribs, clavicles, scapulae, and cervical, thoracic, or lumbar vertebrae. However, their lower limbs and pelvic girdles were almost normal. The authors conclude that skeletal development is likely to be jeopardized in the area adjacent to the heart and in the cephalic portion of the body in fetuses with acardius anceps, and suggest vascular deficiency and hypoperfusion as pathogenetic mechanisms in this type of skeletal deformity.

Abnormalities, Severe Teratoid↗
PubMed1997

Intracellular pH and heat sensitivity in two human cancer cell lines.

BACKGROUND AND PURPOSE: The majority of studies which have demonstrated a linear correlation between intracellular pH (pHi) and thermosensitivity have used rodent cell lines. In order to understand the therapeutic potential of this strategy, it is necessary to determine whether similar observations can be obtained with human cancer cells. MATERIALS AND METHODS: Human breast cancer MCF-7, and nasopharyngeal carcinoma CNE-1 cell lines were heated at 43 degrees C under extracellular pH (pHe) conditions of 7.2 or 6.8, +/- NaHCO3. We studied the function of the Na+/H+ antiport, one of the primary membrane regulators of pHi, pHi level, and clonogenic survival after these treatments. RESULTS: After 2-h exposure to 43 degrees C at pHe 7.2, antiport activity in MCF-7 cells was > 50% relative to that of unheated cells, in contrast to < 20% relative activity for CNE-1 cells. Respective survival levels under these conditions were 0.25 and 0.04. The addition of 5-(N-ethyl-N-isoproply) amiloride (EIPA), a potent inhibitor of Na+/H+ antiport, had no effect on MCF-7 cells, but enhanced cytotoxicity for CNE-1 cells, when heated at pHe 6.8 without NaHCO3. Analysis of the correlation between log surviving fraction and pHi demonstrated that this relationship was much steeper for CNE-1 compared to MCF-7 cells. CONCLUSION: The relationship between pHi levels and thermosensitivity observed in rodent cells can also apply to two human cancer cell lines: MCF-7 and CNE-1, with the latter cells being apparently more amenable to manipulations of pHi regulation compared to the former.

Amiloride↗
PubMed1997

First report of distal obstructive uropathy and prune-belly syndrome in an infant with amniotic band syndrome.

We describe the first report of distal obstructive uropathy and prune-belly syndrome in an infant with amniotic band syndrome. Prenatal ultrasonographic examination in the third trimester revealed intermittent oligohydramnios, bilateral hydronephrosis, and megacystis. Postnatally, the infant was found to have a scalp defect, a skin pedicle, pseudosyndactyly and constriction rings on the hands, marked distention of the abdomen, a fibrous band attached to the proximal urethra causing urethral stricture, a swollen penile shaft, bilateral talipes equinovarus, and syndactyly of the feet. Multiple fibrous amniotic bands could be identified in the placenta. Our case shows that fetal distal obstructive uropathy can be associated with the congenital constriction band syndrome.

Adult↗
PubMed1997

Perinatal features of omphalocele-exstrophy-imperforate anus-spinal defects (OEIS complex) associated with large meningomyeloceles and severe limb defects.

Omphalocele-Exstrophy-Imperforate anus-Spinal defects (OEIS complex), a combination of omphalocele, exstrophy of the bladder, an imperforate anus and spinal defects, arises from a single localized defect in the early development of the mesoderm that will later contribute to infraumbilical mesenchyme, cloacal septum, and caudal vertebrae. In this report, we document the perinatal features of two cases of OEIS complex associated with meningomyeloceles and severe lower limb defects, and discuss the prenatal diagnosis, inheritance, and differential diagnosis of this association of malformations. Although long-term survival can be achieved by successful corrective surgery, the associated structural defects such as large meningomyelocele and severe limb aplasia or hypoplasia, as seen in our patient, can influence the patient's quality of life. We would like to emphasize that an accurate prenatal diagnosis of OEIS complex and associated malformations is important for the detailed counseling of the family as well as appropriate perinatal management by the obstetricians, pediatric surgeons, urologists, neurosurgeons, and neonatologists.

Abnormalities, Multiple↗
PubMed1997

Cebocephaly, alobar holoprosencephaly, spina bifida, and sirenomelia in a stillbirth.

Cebocephaly and sirenomelia are uncommon birth defects. Their association is extremely rare; however, the presence of spina bifida with both conditions is not unexpected. We report on a female still-birth with cebocephaly, alobar holoprosencephaly, cleft palate, lumbar spina bifida, sirenomelia, a single umbilical artery, and a 46,XX karyotype, but without maternal diabetes mellitus. Our case adds to the examples of overlapping cephalic and caudal defects, possibly related to vulnerability of the midline developmental field or axial mesodermal dysplasia spectrum.

Abnormalities, Multiple↗
PubMed1997

Prenatal diagnosis, pathology, and genetic study of fetus in fetu.

We report the prenatal diagnosis, pathology, cytogenetics, and molecular studies of a retroperitoneal fetus in fetu. Prenatal ultrasonography of the host fetus in the third trimester showed an anencephalic, acardiac mass with identifiable extremities and spine within an intra-abdominal cystic mass. Pathological examination revealed a fetiform mass weighing 20 g with four extremities, digits, vertebral bodies, an oral cavity with developing teeth, primitive male external genitalia, a urinary bladder, a cloaca with an external opening, large intestines, a membranous capsule, and an umbilical cord with one artery, one vein, and Wharton's jelly. Histological examination demonstrated nerve bundles in the fibrocollagenous tissue below the cuboidal surface epithelium of the membranous capsule, and absence of lamina elastica interna and vasa vasorum in the single artery of the umbilical cord. Both the host infant and the fetus in fetu had a normal 46,XY karyotype. Molecular analysis using informative genetic markers showed no genetic difference between the host infant and the fetiform mass. We report this case as an unusual example of fetus in fetu in co-existence with an amnion-like membrane containing nerve bundles and with a well-formed umbilical cord. We demonstrate that fetus in fetu can be diagnosed prenatally if the fetiform mass has well-developed limbs and spine. We emphasize the necessity for suspicion of fetus in fetu when a well-defined encapsulated cystic mass with calcified solid components is detected prenatally in a fetus by ultrasonography.

Adult↗
PubMed1997

Progressive fetal axillary cystic lymphangioma with coexistent naevus flammeus.

We report the rare occurrence of a progressive fetal axillary cystic lymphangioma coexistent with an overlying naevus flammeus. The fetus at 22 weeks' gestation was found to have a 37 x 35 mm left axillary multiloculated mass without colour-flow imaging. Amniocentesis showed a normal 46,XX karyotype. Multiple fine-needle aspirations of the mass in the second and third trimesters obtained blood-stained chocolate-coloured fluid containing numerous erythrocytes and lymphocytes but proved ineffective in lessening the progressive growth of the mass. The mother underwent caesarean delivery and a healthy neonate was born with a 141 x 81 mm left axillary cystic lymphangioma and a 50 x 35 mm coexistent naevus flammeus. The neonate was well after simple excision of the lesions. Although cystic lymphangiomas arising in the axilla enlarge progressively during fetal life, our case suggests a good prognosis and except for genetic evaluation, no prenatal intervention is required.

Adult↗
PubMed1997

Cutis marmorata telangiectatica congenita associated with an elevated maternal serum human chorionic gonadotrophin level and transitory isolated fetal ascites.

A 34-year-old woman with an abnormal maternal serum screening result and a Down syndrome risk of 1:60 calculated from a maternal serum alpha-fetoprotein (AFP) value of 1.4 multiples of the median (MoM) and a human chorionic gonadotrophin (hCG) level of 4.32 MoM at 18 weeks' gestation was found to have isolated fetal ascites at 23 weeks' gestation. Spontaneous resolution occurred 10 weeks after the initial presentation. After birth, the neonate had generalized cutis marmorata telangiectatica congenita (CMTC), large vascular plaques on the scalp with superficial ulceration and crusts, a small atrial septal defect, a patent ductus arteriosus, hepatomegaly, micrognathia, seizures, an abnormal electroencephalogram, congenital retinal detachment, glaucoma and widely spaced toes. Our patient illustrates that CMTC in utero may be associated with a markedly elevated maternal serum hCG level as well as transitory isolated fetal ascites. However, such associations can be coincidental and further collaborative studies and cases will be necessary before it can be determined that a disproportionately elevated hCG level and transitory isolated fetal ascites are predictive of CMTC in utero.

Abnormalities, Multiple↗
PubMed1997

Prenatal diagnosis of a deletion of 18q in a fetus associated with multiple-marker screen positive results.

We report here the observations of positive maternal serum screening tests for Down syndrome, cytogenetic and molecular analysis, and dysmorphic fetal features in a pregnancy with 18q-syndrome. A 33-year-old primigravida was referred for genetic counselling because of multiple-marker screen positive results. At 14 weeks' gestation, the woman had a Down syndrome risk of 1:107 calculated from a maternal serum alpha-fetoprotein (MSAFP) level of 1.49 multiples of the median (MOM), a total human chorionic gonadotrophin (hCG) level of 2.42 MOM, and a serum unconjugated oestriol (uE3) level of 0.55 MOM. At 17 weeks' gestation, a repeat test showed a Down syndrome risk of 1:10 calculated from an MSAFP level of 1.09 MOM and a free beta-hCG level of 12.3 MOM. Genetic amniocentesis revealed a de novo deletion of 18q22.2-qter. Intrauterine fetal death occurred at 21 weeks' gestation. At birth, the fetus manifested clinical findings of the 18q-syndrome. The phenotype was correlated with the extent of the deletion. Linkage analysis of the family confirmed the extent and paternal origin of the deletion.

Adult↗
PubMed1997

Cytotoxic effects of Ad5CMV-p53 expression in two human nasopharyngeal carcinoma cell lines.

Nasopharyngeal carcinoma (NPC) is a malignant disease of the head/neck region with a 5-year survival level of approximately 65%. To explore novel therapeutic strategies in the management of this disease, the potential of Ad5CMV-p53-mediated gene transfer to NPC cells was investigated in vitro. Two NPC cell lines, CNE-1 and CNE-2Z, were infected with either Ad5CMV-p53 or Ad5CMV-beta-galactosidase and evaluated for transduction efficiency and cytotoxicity. At a multiplicity of infection of 50 plaque-forming units (pfu)/cell, Ad5CMV-beta-galactosidase infection and beta-galactosidase expression were detected in almost 100% of treated NPC cells. High levels of recombinant p53 protein expression were also observed in the NPC cell lines when treated with Ad5CMV-p53 at 50 pfu/cell. Expression of recombinant p53 was dose and time dependent, with peak levels observed at 24 h. A marked increase in WAF1/CIP1 expression was also observed in NPC cells after Ad5CMV-p53 infection. Expression of bcl-2 and bax were minimally detectable at baseline; infection with Ad5CMV-p53 induced no changes in the protein levels in the NPC cells. Growth of NPC cells treated with Ad5CMV-p53 was observed to be significantly inhibited when determined by either the 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide or clonogenic assay. Infection with Ad5CMV-p53 at 25 pfu/cell resulted in survival levels of 0.35 and 11% in CNE-1 and CNE-2Z cells, respectively. Chromatin condensation and DNA fragmentation were also observed, demonstrating that these cells were undergoing apoptosis. However, when GM38 (normal human fibroblasts) were subjected to identical treatments, they demonstrated significantly lower infection efficiency and transgene expression and were resistant to Ad5CMV-p53-mediated cytotoxicity. These data demonstrate the efficacy of Ad5CMV-p53-mediated gene therapy in human NPC, thus warranting additional investigations of this therapeutic strategy.

Adenoviruses, Human↗
PubMed1996

Radiotherapy with or without hyperthermia in the treatment of superficial localized breast cancer: results from five randomized controlled trials. International Collaborative Hyperthermia Group.

PURPOSE: Claims for the value of hyperthermia as an adjunct to radiotherapy in the treatment of cancer have mostly been based on small Phase I or II trials. To test the benefit of this form of treatment, randomized Phase III trials were needed. METHODS AND MATERIALS: Five randomized trials addressing this question were started between 1988 and 1991. In these trials, patients were eligible if they had advanced primary or recurrent breast cancer, and local radiotherapy was indicated in preference to surgery. In addition, heating of the lesions and treatment with a prescribed (re)irradiation schedule had to be feasible and informed consent was obtained. The primary endpoint of all trials was local complete response. Slow recruitment led to a decision to collaborate and combine the trial results in one analysis, and report them simultaneously in one publication. Interim analyses were carried out and the trials were closed to recruitment when a previously agreed statistically significant difference in complete response rate was observed in the two larger trials. RESULTS: We report on pretreatment characteristics, the treatments received, the local response observed, duration of response, time to local failure, distant progression and survival, and treatment toxicity of the 306 patients randomized. The overall CR rate for RT alone was 41% and for the combined treatment arm was 59%, giving, after stratification by trial, an odds ratio of 2.3. Not all trials demonstrated an advantage for the combined treatment, although the 95% confidence intervals of the different trials all contain the pooled odds ratio. The greatest effect was observed in patients with recurrent lesions in previously irradiated areas, where further irradiation was limited to low doses. CONCLUSION: The combined result of the five trials has demonstrated the efficacy of hyperthermia as an adjunct to radiotherapy for treatment of recurrent breast cancer. The implication of these encouraging results is that hyperthermia appears to have an important role in the clinical management of this disease, and there should be no doubt that further studies of the use of hyperthermia are warranted.

Breast Neoplasms↗
PubMed1996

CVS-exposed limb deficiency defects with or without other birth defects: presentation of six cases born during a period of nine years.

We report on six cases with CVS-exposed limb-"reduction" defects born in our hospital during a period of 9 years (1986-1994). Four cases were associated with other birth defects. One had an oromandibular-limb hypogenesis syndrome with a cleft lip and jejunal atresia, a second had an oromandibular-limb hypogenesis (Hanhart) syndrome, a third had severe flexion deformity at the hips and hyperextension at the knees with meconium peritonitis and intestinal obstruction, and a fourth had Poland anomaly. Detailed clinical descriptions, prenatal diagnosis, photographs, and radiographs are presented. Our presentation adds to the information on severe limb abnormalities after CVS and suggests CVS-exposed limb defects may be associated with other birth defects resulting from vascular insufficiency or intrauterine compression. We suggest that detailed post-CVS sonographic followups are necessary for each CVS-exposed case to identify not only the possible fetal limb reduction, but also vascular disruption-type malformations and compressive deformities.

Abnormalities, Multiple↗