Biomedical subjects

S W Leung

Publications and source records attributed to S W Leung.

At least 19 recordsLinked to original sources

PubMed1999

Management of choroidal melanomas with linear accelerator-based stereotactic radiosurgery.

PURPOSE: To discuss the technical aspect, dose prescription, clinical results, and biological responsiveness of linear accelerator-based stereotactic radiosurgery for choroidal melanoma. METHODS: From March 1995 to December 1995, three choroidal melanoma patients were treated with Linac-based radiosurgery in our department. Two patients underwent one dose of radiosurgery with 18 and 20 Gy in single fraction, respectively. The third patient received two doses of radiosurgery with a total dose of 35 Gy. RESULTS: Follow-up time ranged from 19 to 25 months (median: 24 months). One patient had near-total regression, while the other two patients had partial response on the last MR images. Visual acuity was deteriorated in all patients. One patient developed a radiation-induced cataract in the treated eye. CONCLUSION: Linac-based radiosurgery is technically feasible for management of choroidal melanoma. Although visual acuity was not improved in these patients, they appreciated the preserving of the eyeball without affecting their general appearance.

Adult↗

PubMed1998

Local vaginal anesthesia during high-dose-rate intracavitary brachytherapy for cervical cancer.

PURPOSE: To evaluate the clinical efficacy of local vaginal lidocaine application for pain relief during high-dose-rate (HDR) intracavitary brachytherapy for patients with cervical cancer, and to investigate sequential changes in serum levels of lidocaine during the procedures. METHODS AND MATERIALS: This prospective study was designed to examine the analgesic effect, physical response, and side effects of local anesthesia during HDR intracavitary brachytherapy. Forty patients were enrolled. All patients received 10-15 MV X-rays to the pelvis with a total dose of 45-59.4 Gy 5-6 weeks before undergoing HDR intracavitary brachytherapy. All patients underwent first intracavitary brachytherapy under general anesthesia. These patients were randomly allocated to receive one of two different treatment protocols as follows: (1) treatment session - control session - treatment session - control session; or (2) control session - treatment session- control session - treatment session. In the treatment sessions, topical anesthesia was administered using 4 ml of 10% lidocaine solution sprayed liberally on the cervix and vagina during intracavitary brachytherapy. In the control sessions, a placebo was administered in the same manner during brachytherapy. The Hensche's applicators for brachytherapy were inserted into the cervix and vagina 5 min after lidocaine application. The visual analogue scale (VAS) was used to assess pain and discomfort during brachytherapy. Blood pressure and heart rates were measured to evaluate the physiological response. Another prospective study was then performed to investigate the sequential changes of serum lidocaine levels during the anesthetic procedure. Eleven additional patients with similar disease state and demographic characteristics were enrolled and blood samples were obtained before, and 5, 15, 30, and 45 min after the initiation of lidocaine application. RESULTS: The mean VAS values recorded during the treatment sessions and control sessions were 49.9 +/- 24.1 versus 60.1 +/- 24.8, respectively. The value of VAS in the treatment session was significantly lower than that of the control session (p < 0.001). No statistically significant differences were found in the changes of blood pressure and heart rate and in the incidence of side effects during these two types of sessions (p > 0.05). In the drug-level study, serum levels of lidocaine reached a peak 5 min after the initiation of local anesthesia. The mean peak concentrations (Cmax) of lidocaine were 0.50 +/- 0.45 microg/ml. CONCLUSION: Local vaginal anesthesia with 10% lidocaine solution can significantly decrease the degree of painful sensation during HDR intracavitary brachytherapy, and is safe to administer for the procedure for cervical cancer.

Anesthesia, Local↗

PubMed1998

The human hypoxia-inducible factor 1alpha gene: HIF1A structure and evolutionary conservation.

The HIF1A gene encodes the HIF-1alpha subunit of hypoxia-inducible factor 1, a transcription factor that is essential for cardiovascular development and systemic O2 homeostasis. HIF1A consists of 15 exons that are interrupted by introns at the same locations as in the mouse Hif1a gene, although sequences mediating alternative splicing and alternative translation initiation events in the mouse are not present in the human gene. Placement of introns differs between HIF1A and EPAS1, which encodes the human HIF-2alpha protein. Transcription of the HIF1A gene was initiated over a 15-nt region downstream of two SP1 sites. A 0.7-kb region of 5' flanking sequences functioned as a strong promoter in transient expression assays. Comparison of 0.8 kb of 5' flanking and 5' untranslated sequences from the HIF1A and Hif1a genes revealed 70% identity. The proximal 300 bp of 5' flanking sequences was 83% identical, including the SP1 sites and transcription initiation sites. These results suggest evolutionary selection for maintenance of HIF1A structure, function, and regulation.

Amino Acid Sequence↗

PubMed1998

Impact of the extent of parametrial involvement in patients with carcinoma of the uterine cervix.

PURPOSE: A scoring system is proposed to measure the extent of parametrial involvement and predict treatment outcome in patients with carcinoma of the uterine cervix. METHODS AND MATERIALS: 244 patients with FIGO Stage IIB (n = 146) or IIIB (n = 98) carcinoma of the uterine cervix were treated by radical radiotherapy from October 1987 to June 1992. Impact of the extent of parametrial involvement on outcome was studied. All patients were scored by the newly introduced scoring system described as follows: score 1, tumor extending <1/2 the distance to the pelvic side wall; score 2, tumor extending >1/2 the distance to the pelvic side wall but not to pelvic side wall; score 3, tumor extending to the pelvic side wall. The score in each patient was defined as the sum of the scores of both the left and right parametrial tumor extent. RESULTS: There were 53, 47, 61, 34, 25, and 24 patients in score 1, 2, 3, 4, 5, and 6, respectively. All 244 patients were subdivided into three groups described as follows: score 1 and 2, group I; score 3 and 4, group II; score 5 and 6, group III. In univariate analysis, lower score groups had better overall survival rate (OS), disease-free survival rate (DFS), local control rate (LC), and distant metastasis-free rate (DMF) than higher score groups including groups I vs. II, II vs. III, or I vs. III. The differences were all statistically significant except for the difference of the DMF in group I vs. II. In multivariate analysis, score (range 1-6) was also statistically significant in OS (p < 0.0001), DFS (p = 0.0015), LC (p = 0.0032), and DMF (p = 0.0141). CONCLUSIONS: The data suggested that the new scoring system defined by pelvic examination is a convenient, simple, and reliable method of measuring the degree of parametrial extension and predicting the outcome of patients with parametrial disease.

Adult↗

PubMed1998

Cellular and developmental control of O2 homeostasis by hypoxia-inducible factor 1 alpha.

Hypoxia is an essential developmental and physiological stimulus that plays a key role in the pathophysiology of cancer, heart attack, stroke, and other major causes of mortality. Hypoxia-inducible factor 1 (HIF-1) is the only known mammalian transcription factor expressed uniquely in response to physiologically relevant levels of hypoxia. We now report that in Hif1a-/- embryonic stem cells that did not express the O2-regulated HIF-1alpha subunit, levels of mRNAs encoding glucose transporters and glycolytic enzymes were reduced, and cellular proliferation was impaired. Vascular endothelial growth factor mRNA expression was also markedly decreased in hypoxic Hif1a-/- embryonic stem cells and cystic embryoid bodies. Complete deficiency of HIF-1alpha resulted in developmental arrest and lethality by E11 of Hif1a-/- embryos that manifested neural tube defects, cardiovascular malformations, and marked cell death within the cephalic mesenchyme. In Hif1a+/+ embryos, HIF-1alpha expression increased between E8.5 and E9.5, coincident with the onset of developmental defects and cell death in Hif1a-/- embryos. These results demonstrate that HIF-1alpha is a master regulator of cellular and developmental O2 homeostasis.

Animals↗

PubMed1998

The correlation of acute toxicity and late rectal injury in radiotherapy for cervical carcinoma: evidence suggestive of consequential late effect (CQLE).

PURPOSE: To correlate the acute toxicity during pelvic irradiation and the development of late rectal injury following radiation therapy for cervical carcinoma. METHODS AND MATERIALS: Two hundred and twenty patients treated with curative-intent radiation therapy between November 1987 and January 1992 were analyzed. Patients were treated initially with external beam irradiation, 40-44 Gy/20-22 fractions to whole pelvis, followed by high dose rate intracavitary brachytherapy, 7.2 Gy to point A for 3 fractions. Severity of diarrhea during radiation therapy was scored according to six criteria: fecal characteristics, frequency, onset, prescription of antidiarrheal agents, body weight loss during irradiation, and extramedical care needed. Patients were categorized as group ND (no obvious diarrhea), group MD (moderate diarrhea), and group SD (severe diarrhea) for sum score 0-1, 2-5, and > or = 6, respectively. The rate of radiation proctitis was expressed, analyzed, and compared with actuarial proctitis-free rate and prevalence. RESULTS: 1) According to the score, 76 (35%), 89 (40%), and 55 (25%) patients were categorized as group ND, group MD, and group SD, respectively. Distribution of patients and treatment characteristics among the three groups appeared similar. Patients treated with a larger field size, > or = 16.5 cm2, tended to have increased severity of diarrhea. 2) Overall, 103 patients (47%, 103 of 220) developed radiation proctitis. Twenty-one patients were in group ND (28%, 21 of 76), 43 in group MD (48%, 43 of 89), and 39 in group SD (71%, 39 of 55). 3) The five-year actuarial proctitis-free rate was 72, 52, and 29% for group ND, MD, and SD, respectively (p < 0.005). 4) Taking time evolution and recoverability into account, the effect of diarrhea on the prevalence of radiation proctitis remained statistically significant at the first through the fourth year after irradiation. 5) Severity of radiation proctitis and severity of diarrhea were not correlated (Spearman's rank correlation coefficient r(s) = 0.229, p = 0.098). 6) Cox's multivariate analysis revealed that severity of diarrhea was the only factor that significantly correlated with the development of radiation proctitis. CONCLUSION: Patients with increased acute toxicity and diarrhea during radiation therapy of cervical carcinoma significantly increased the risk of late rectal injury. This result suggested that early excessive damage of acute-responding component of rectal wall may play an important role in the initiation of late rectal injury. Radiation proctitis can be accounted, in part, as a consequential late effect.

Adult↗

PubMed1998

Effect of acetic acid on telomerase activity in cervical intraepithelial neoplasia.

OBJECTIVE: To evaluate whether the telomerase activity in CIN lesions can be affected by a chemical solution of acetic acid, which is required to apply to the cervix prior to colposcopy-directed biopsy. MATERIALS AND METHODS: Thirty-five patients with histologically confirmed high-grade squamous intraepithelial lesions of the cervix entered the study. Two specimens were collected from each patient, one before and one after the cervix was swabbed with 5% acetic acid. The standard telomeric repeat assay protocol (TRAP) was used to examine telomerase activity in these fresh frozen tissue samples. Normal cervical tissues from 10 control individuals were also examined for the presence of telomerase activity. A total of 80 specimens was analyzed. RESULTS: Telomerase activity was detectable in 27 of 35 (77.1%) fresh tissue samples, 15 of 35 (42.9%) tissue samples swabbed with 5% acetic acid, and 0 of 10 (0%) normal cervical tissue samples, respectively. Twelve samples became telomerase negative after 5% acetic acid applied. Among the 15 telomerase-positive tissue samples swabbed with 5% acetic acid, 12 had relative weak telomerase activity compared to corresponding fresh tissue samples, the other 3 remained the same. Therefore, it is concluded that telomerase activity was affected by 5% acetic acid in 24 of 27 (88.9%) samples. Telomerase activity in HeLa cell line was also inhibited by 5% acetic acid. CONCLUSION: We reported a relative high percentage of telomerase expression in high-grade CIN lesions when compared with previous reports. If detection of telomerase activity is to become a tool for diagnosis and prognosis of cervical neoplasias, applying acetic acid prior to colposcopy-directed biopsy that is submitted for telomerase assay should be avoided in order to increase the detection rate.

Acetic Acid↗

PubMed1998

The prognostic factors of lung cancer patients with brain metastases treated with radiotherapy.

PURPOSE: To analyze the prognostic factors of lung cancer with brain metastases (BM) and evaluate the role of cranial irradiation on survival. METHODS AND MATERIALS: From 1987 to 1994, 159 lung cancer patients with CT scan documented BM were reviewed. All of them underwent cranial irradiation (median radiation dose: 30 Gy). Chemotherapy and surgery of BM were performed in 21 and 10 cases, respectively. RESULTS: Overall median survival was 3.5 months and one year survival rate was 10.69%. Univariate analysis showed that the significant factors were performance status, age, total radiation dose to brain, BM as the first metastasis, neurosurgery, symptoms of urine/stool incontinence, and synchronous BM. Multivariate analysis indicated that (1) performance status (p = 0.0002), (2) total radiation dose (p = 0.0032), (3) BM as the first metastasis (p = 0.0449), (4) neurosurgery (p = 0.0233), (5) symptoms of urine/stool incontinence (p = 0.0002), and (6) the presence of a midline shift on cranial CT scans (p = 0.0063) were significant prognostic factors. CONCLUSION: The prognosis of BM in lung cancer patients is extremely poor. Radiotherapy appears as an effective means of palliation with 75% overall symptomatic response rate. Higher radiation dose (> or = 30 Gy) and neurosurgery are associated with longer survival. Good performance status, BM as the first metastasis, absence of sphincter dysfunction, and midline shift on CT scans are favorable prognostic predictors. The role of midline shift is very interesting and needs to be explored further.

Adult↗

PubMed1998

Total skin electron beam irradiation in scleromyxoedema.

We report a 44-year-old male with generalized progressive scleromyxoedema treated by total skin electron beam therapy (TSEBT) which produced a marked improvement in the skin lesion. TSEBT can provide effective treatment for patients with widespread skin involvement in scleromyxoedema.

Adult↗

PubMed1998

Survival advantages and complications of adjuvant therapy in early-stage cervical cancer with pelvic node metastasis.

BACKGROUND: Patients with early-stage cervical cancer who have pelvic node metastasis usually need adjuvant therapy after surgery for improvement of the length of survival. We attempted to determine the survival advantages and complications associated with different adjuvant therapeutic modalities. MATERIALS AND METHODS: Eighty-seven patients with clinical stage Ib and IIa cervical cancer were treated with radical hysterectomy from July 1986 through December 1994 were reviewed retrospectively. All had had lymph node metastasis. The patients were divided into three groups according to the different adjuvant therapeutic approaches utilized: radiation (group I, n = 43), chemotherapy (group II, n = 23), and chemoirradiation (group III, n = 21). RESULTS: There was no significant difference among these three groups in the 5-year relapse-free survival rate (group I: 63%, group II: 62%, group III: 51%, p = 0.785). The recurrence rates among these three groups were found to be similar (group I: 32.6%, group II: 39.1%, group III: 47.6%, p = 0.331). However, most of the recurrence in patients who had received pelvic radiation was at a distant site (group I: 79%, group III: 80%) as compared to the patients who had received chemotherapy only (group II: 33%), and the differences were significant (p = 0.020). The rates of complications, such as severe leukopenia, lymphedema with cellulitis, proctosigmoiditis and ileus, were found to be lower in the chemotherapeutic group. CONCLUSION: Although we failed to demonstrate the survival advantages of different adjuvant therapeutic approaches, we still favor chemotherapy as an adjuvant basis because it is the least toxic of the regimens.

Adult↗

PubMed1998

Hypertrophic osteoarthropathy in nasopharyngeal carcinoma patients: two cases report.

Hypertrophic osteoarthropathy (HOA) is a rheumatic disorder characterized by digital clubbing, bone pain, and arthralgia. HOA can be idiopathic or secondary to a variety of pulmonary, cardiogenic, or malignant disorders. We present 2 male patients, aged 46 and 42, with advanced nasopharyngeal carcinoma (NPC) who developed HOA 1-4 years after radiotherapy. Differential diagnosis between HOA and coexisting bone metastasis must be made with caution. We found bone scintigraphy to be the most sensitive tool to distinguish between these 2 disease. Intense symmetrical uptake of radioisotope along the cortex of long bones, so-called parallel tract sign, is typical. Plain radiographs demonstrating prominent periosteal reaction were also effective for this. The rheumatic manifestation of HOA was paraneoplastic and related to pulmonary metastasis. The clinical manifestation of the 2 patients suggested that pulmonary metastasis should be suspected in NPC patients when HOA appears.

Adult↗

PubMed1997

Lying-on position of total skin electron therapy.

PURPOSE: A technique for whole-body electron therapy with the patient in a lying position has been developed. This technique allows Total Skin Electron Therapy (TSET) for those patients who were previously unable to be treated in a conventional standing position. METHODS AND MATERIALS: This study was carried out on a Varian 2100C linear accelerator with a 6 MeV high dose rate electron beam. The collimator was open to a width of 36 x 36 cm. There were two main procedures, with six dual-field techniques: 1) two static AP/PA vertical dual fields (VDF): the patient laid on the floor transversely under the collimator when the gantry was in a vertical position. A 0.6 cm acrylic board was placed 15 cm away from the patient, then the gantry was rotated 25 degrees clockwise and counterclockwise to treat the patient in the supine and prone positions, respectively. 2) Four oblique junction fields (OJF): the patient laid on the floor in a prone and supine position parallel to the wave guide at (227 - body thickness x tan 60 degrees) cm away from the vertical axis of the gantry, then the gantry was rotated 60 degrees toward the patient. A 0.6 cm acrylic board was placed 15 cm away from the patient perpendicular to the beam. The patient was move along the field central axis. It allowed the patient's body to be within the 160 cm effective treatment profile. When the patient's body axis move 5 degrees toward the lateral side of the field central axis, we could obtain a better dose distribution in the vertex of the scalp and the soles of the feet. The angle of the VDF was measured by chamber detectors to obtain the effective treatment profile. Likewise, the optimal profile for the OJF was determined by the same procedures. The Rando phantom was used to measure the superficial dose of the body. RESULTS: The dimension of effective treatment profile for the VDF was 188 x 72 cm at 87% dose level For the OJF, we had to move the patient along the field central axis to obtain the effective treatment profile in a 180 x 85 cm dimension at a 87% dose level. The vertex and sole dose measured in this setup was in the range of 80-88%. CONCLUSIONS: The empirical data showed that the lying-on position for TSET was technically feasible. The dose distribution in the body surface was also compatible with the Stanford standing technique. The nonambulatory skin malignancy patient can be treated in a comfortable and reproducible position.

Electrons↗

PubMed1997

Transactivation and inhibitory domains of hypoxia-inducible factor 1alpha. Modulation of transcriptional activity by oxygen tension.

Hypoxia-inducible factor 1 (HIF-1) binds to cis-acting hypoxia-response elements within the erythropoietin, vascular endothelial growth factor, and other genes to activate transcription in hypoxic cells. HIF-1 is a basic helix-loop-helix transcription factor composed of HIF-1alpha and HIF-1beta subunits. Here, we demonstrate that HIF-1alpha contains two transactivation domains located between amino acids 531 and 826. When expressed as GAL4 fusion proteins, the transcriptional activity of these domains increased in response to hypoxia. Fusion protein levels were unaffected by changes in cellular O2 tension. Two minimal transactivation domains were localized to amino acid residues 531-575 and 786-826. The transcriptional activation domains were separated by amino acid sequences that inhibited transactivation. Deletion analysis demonstrated that the gradual removal of inhibitory domain sequences (amino acids 576-785) was associated with progressively increased transcriptional activity of the fusion proteins, especially in cells cultured at 20% O2. Transcriptional activity of GAL4/HIF-1alpha fusion proteins was increased in cells exposed to 1% O2, cobalt chloride, or desferrioxamine, each of which also increased levels of endogenous HIF-1alpha protein but did not affect fusion protein levels. These results indicate that increased transcriptional activity mediated by HIF-1 in hypoxic cells results from both increased HIF-1alpha protein levels and increased activity of HIF-1alpha transactivation domains.

Animals↗

PubMed1997

High-dose-rate intracavitary brachytherapy (HDR-IC) in treatment of cervical carcinoma: 5-year results and implication of increased low-grade rectal complication on initiation of an HDR-IC fractionation scheme.

PURPOSE: To report the treatment results and rectal/bladder complications of cervical carcinoma radically treated with high-dose-rate intracavitary brachytherapy (HDR-IC). The current policy of using three-fraction scheme was examined. METHODS AND MATERIALS: Between November 1987 and August 1990, 173 patients with cervical carcinoma were treated with curative-intent radiation therapy. Whole pelvic irradiation was administered with 10-MV X ray. Dose to the central cervix was 40-44 Gy in 20-22 fractions, following by pelvic wall boost 6-14 Gy in three to seven fractions with central shielding. 60Co sources were used for HDR-IC, and 7.2 Gy was given to Point A for three applications, 1-2 weeks apart. Duration of follow-up was 5-7.8 years. RESULTS: Twenty-eight patients (16%) developed central-regional recurrences. Overall 5-year actuarial pelvic control rate was 83%. By stage, 5-year actuarial pelvic control rates were 94%, 87%, and 72% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Thirty-one patients (18%) developed distant metastasis. Overall 5-year actuarial survival rate was 58%. By stage, 5-year actuarial survival rates were 79%, 59%, and 41% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Sixty-six (38%) and 19 patients (11%) developed rectal and bladder complications, respectively. For rectal complication, the overall actuarial rate was 38% at 5 years. By grade, 5-year actuarial rectal complication rates were 24%, 15%, 4%, and 3% for Grades 1-4, respectively. Overall prevalence of rectal complications was 37% and 14% at 2 and 5 years, respectively. Prevalence of low-grade rectal complication (Grades 1 and 2) was dominant at 2 years (30%), but declined to 8% at 5 years. Prevalence of high-grade, severe rectal complication (Grades 3 and 4) remained steady at 2 and 5 years (7% and 6%, respectively). Five-year actuarial bladder complication was 9%. Five-year prevalence of bladder complication was 2%. CONCLUSION: Using a three-fraction scheme, survival rate appeared comparable with the existing results of the low-dose-rate technique. The incidence of rectal complication with this scheme remained relatively high. The increased part of rectal complication was predominantly low grade. This result suggested that therapeutic gain with this scheme may not be good enough to circumvent its biologic disadvantage. Numbers of fractions >3 must be considered in future trials.

Adenocarcinoma↗

PubMed1997

Combined-modality therapy for squamous carcinoma of the buccal mucosa: treatment results and prognostic factors.

BACKGROUND: Reports on locoregional control and survival of squamous cell carcinoma of buccal mucosa are scarce in literature. In this study, a single institutions's experience of combined surgery and postoperative radiotherapy (RT) for buccal mucosal malignancy with favorable results was analyzed and presented. The prognostic factors on locoregional control were also discussed. METHODS: From January 1988 to July 1994, 57 patients with squamous cell carcinoma of buccal mucosa treated by surgery and RT were reviewed. The distributions according to American Joint Committee on Cancer (AJCC) staging were: stage II, 6; stage III, 21; and stage IV, 30 patients. Total dose of RT at the buccal area ranged from 45 Gy to 68.4 Gy, median 61.2 Gy. Tumor-related factors (AJCC stage, T stage, histologic grading, pathologic tumor invasion to skin of cheek, adjacent bony structures, and regional lymph nodes) and treatment-related factors (surgical margin, radiation dose, and the time interval between operation and RT) were analyzed to determine their influence on locoregional control. RESULTS: Three-year actuarial locoregional control rate, overall survival rate, and disease-specific survival rates were 64%, 55%, and 62%, respectively. Ten of these 22 patients (45%) with recurrent tumors were reoperated, but only 2 patients were successfully salvaged. Positive surgical margin and tumor invasion to skin of cheek were significantly poor prognostic factors on locoregional control by univariate analysis. In multivariate analysis, tumor invasion to skin of cheek was the only prognostic factor (p = .0014). CONCLUSIONS: Locoregional failure was the major cause of death for squamous buccal mucosa cancers managed with surgery and RT. Few recurrences could be detected early and successfully salvaged. Skin of cheek involvement is an important prognostic factor for buccal mucosa cancers.

Actuarial Analysis↗

PubMed1997

Effect of megestrol acetate and prepulsid on nutritional improvement in patients with head and neck cancers undergoing radiotherapy.

BACKGROUND AND PURPOSE: Anorexia is a common problem in cancer patients who receive radiotherapy. In this current study, we attempt to determine the effect of megestrol acetate and prepulsid on appetite and nutritional improvement in patients with head and neck cancers undergoing radiotherapy. MATERIALS AND METHODS: One hundred twenty-nine consecutive patients with head and neck cancers treated between July 1993 and June 1994 were prospectively randomized to receive either megestrol acetate, 40 mg qid (megace group), prepulsid, 5 mg tid (cisapride group), or a placebo treatment (control group) during radiotherapy. Before radiotherapy, body weight (kg), appetite score, performance status, biochemical parameters and hematological parameters were evaluated, and the above-noted clinical and biochemical parameters were assessed and recorded every other week. All patients received 6- 10 MV X-rays or Co-60 gamma-ray to head and neck region for a full course of radiotherapy, 61.2-75.6 Gy/7-9 weeks. RESULTS: Forty-eight patients were enrolled in the megace group, 41 patients in the cisapride group, and 40 patients in the control group. At the 2nd, 4th, 6th and 8th week, as the radiation dose escalated, the megace group had significantly less body weight loss than did the cisapride and control groups (P = 0.045, 0.024, 0.006, 0.003, respectively). The appetite scores of the megace group were significantly higher than those of the cisapride and control groups (P = 0.0001). However, there were no statistically significant differences in the change of albumin level among these three groups at the 2nd, 4th, 6th and 8th week (P > 0.05, respectively). CONCLUSIONS: Megestrol acetate can significantly decrease the degree of body weight loss, and can prevent the deterioration of appetite in patients with head and neck cancers receiving radiotherapy. However, prepulsid lacks the above-mentioned clinical benefits.

Adult↗

PubMed1997

The relapse patterns and outcome of postoperative recurrent tongue cancer.

PURPOSE: The relapse patterns and salvage treatment results for patients who developed locoregional recurrence after surgery for squamous cell carcinoma of the tongue were retrospectively analyzed. MATERIALS AND METHODS: Between April 1986 and January 1995, 77 cases with recurrent squamous cell carcinoma of the tongue were evaluated. Most of them were males in the early stages of initial disease. Although the surgical margins were negative in most cases (67 of 77), relapse eventually occurred. The relapse patterns showed 15 patients with primary recurrence, 45 patients with regional neck lymph node (LN) relapse, and 17 patients with relapse in both sites. RESULTS: Salvage treatment was given to most of the patients, but their median survival time was only 9 months. Survival data were analyzed and compared with different types of relapse patterns, salvage treatments, disease-free intervals, age, and sex. In univariate analysis, the neck LN relapse and shorter relapse-free interval (< 6 months) were poor prognostic factors (P < .05), and surgical treatment showed a trend for better salvage results (P = .0575). In multivariate analysis, patients with neck LN relapse had the worst outcome (P < .05). CONCLUSIONS: Recurrence of tongue cancer is not uncommon, but there are little data in literature regarding the prognosis. Although this study showed poor salvage results, various prognoses could be predicted on the bases of the different relapse patterns and salvage methods.

Adult↗

PubMed1997

Endothelial dysfunction exacerbates the impairment of relaxation by lysophosphatidylcholine in porcine coronary artery.

1. Current evidence suggests that lysophosphatidylcholine (LPC), a component found in oxidized low-density lipoprotein (Ox-LDL), inhibits endothelium-dependent relaxation (EDR) mediated by endothelium-derived relaxing factor (EDRF) and endothelium-derived hyperpolarizing factor (EDHF). An objective of the present study was to characterize the roles of the different elements of EDR in LPC-induced impairment within the porcine coronary artery. Concomitantly, we sought to determine whether impairment of one component of EDR would increase the sensitivity of the endothelium to LPC. 2. Bradykinin (0.1 nmol/L -0.3 mumol/L) relaxed U46,619 (30 nmol/L)-precontracted porcine coronary artery rings in a concentration-dependent manner. A reduction in the bradykinin-elicited response was observed in NG-nitro-L-arginine methyl ester (L-NAME; 300 mumol/L)- and ouabain (50 mumol/L)-treated rings. Pretreatment with LPC (20 mumol/L), which on its own had no effect on normal endothelial relaxation, resulted in further inhibition of EDRF- and EDHF-induced relaxations. 3. Our results demonstrate that EDRF and EDHF are the primary mediators of EDR in the porcine coronary artery. Our data also show that while a low concentration of LPC (20 mumol/L) does not impair EDR, it can evoke vascular dysfunction following blockade of either the effects of EDRF or EDHF. Therefore, these data suggest that the partially damaged vascular endothelium could be more sensitive to threshold levels of this atherogenic phospholipid.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗