PubMed Health⌕ Search

Biomedical subjects

A T Huang

Publications and source records attributed to A T Huang.

At least 19 recordsLinked to original sources
PubMed2001

Unresectable hepatocellular carcinoma treated with radiotherapy and/or chemoembolization.

The purpose of our study was to evaluate the outcome, patterns of failure, and toxicity for patients with unresectable hepatocellular carcinoma (HCC) treated with radiotherapy, transcatheter arterial chemoembolization (TACE), or combined TACE and radiotherapy. Forty-two patients with unresectable HCC were treated with combined radiotherapy and TACE (TACE+RT group, 17 patients), radiotherapy alone (RT group, 9 patients), or with TACE alone (TACE group, 16 patients). Mean dose of radiation was 46.9 +/- 5.8 Gy in a daily fraction of 1.8 to 2 Gy, directed only to the cancer-involved areas of the liver. TACE was performed with a combination of Lipiodol, doxorubicin, cisplatin, and mitomycin C, followed by Gelfoam or Ivalon embolization. Tumor size was smaller in the TACE group (mean: 5.4 cm) compared with the TACE+RT group (8.6 cm) and the RT group (13.1 cm) (P = 0.0003). The median follow-up was 24 months in the TACE+RT group, 28 months in the RT group, and 23 months in the TACE group. Survival was significantly worse for patients treated with radiotherapy alone due to the selection bias of patients with more advanced disease and compromised condition in this group. In contrast, the TACE+RT and TACE groups had comparable survival (two-year rates: TACE+RT 58%, TACE 56%, P = 0.69). The local control rate for the treated tumors was similar in the TACE+RT and TACE groups (P = 0.11). The intrahepatic recurrence outside the treated tumors was common and similar between these two groups (P = 0.48). The extrahepatic progression-free survival was significantly shorter for patients in the TACE+RT group than in the TACE group (two-year rates: TACE+RT 36%, TACE 100%, P = 0.002). Seven patients died from complications of treatment. Local radiotherapy may be added to treat patients with unresectable HCC, and the control of progression of the treated tumors was promising even in patients with large hepatic tumors. Survival of patients with combined TACE and radiotherapy was similar to that with TACE as the only treatment, while a significant portion of the patients treated with radiotherapy developed extrahepatic metastasis.

Adult↗
PubMed2001

Examining prognostic factors and patterns of failure in nasopharyngeal carcinoma following concomitant radiotherapy and chemotherapy: impact on future clinical trials.

PURPOSE: Concomitant chemotherapy and radiotherapy (CCRT), followed by adjuvant chemotherapy, has improved the outcome of nasopharyngeal carcinoma (NPC). However, the prognosis and patterns of failure after this combined-modality treatment are not yet clear. In this report, the prognostic factors and failure patterns we observed with CCRT may shed new light in the design of future trials. METHODS AND PATIENTS: One hundred forty-nine (149) patients with newly diagnosed and histologically proven NPC were prospectively treated with CCRT followed by adjuvant chemotherapy between April 1990 and December 1997. One hundred and thirty-three (89.3%) patients had MRI of head and neck for primary evaluation before treatment. Radiotherapy was delivered either at 2 Gy per fraction per day up to 70 Gy or 1.2 Gy per fraction, 2 fractions per day, up to 74.4 Gy. Chemotherapy consisted of cisplatin and 5-fluorouracil. According to the AJCC 1997 staging system, 32 patients were in Stage II, 53 in Stage III, and 64 in Stage IV (M0). RESULTS: Univariate analysis revealed that WHO (World Health Organization) Type II histology, T4 classification, and parapharyngeal extension were poor prognostic factors for locoregional control. Multivariate analysis revealed that T4 disease was the most important adverse factor that affects locoregional control, the risk ratio being 5.965 (p = 0.02). Univariate analysis for distant metastasis revealed that T4 and N3 classifications, serum LDH level > 410 U/L (normal range, 180-460), parapharyngeal extension, and infiltration of the clivus were significantly associated with poor prognosis. Multivariate analysis, however, revealed that T4 classification and N3 category were the only two factors that predicted distant metastasis; the risk ratios were 3.994 (p = 0.02) and 3.390 (p = 0.01), respectively. Therefore, based on the risk factor analysis, we were able to identify low-, intermediate-, and high-risk patients. Low-risk patients were those without the risk factors mentioned above. They consisted of Stage II patients with T2aN0, T1N1, and T2aN1 categories and of Stage III patients with T1N2 and T2aN2 categories. Their risk of recurrence is low (4%). Intermediate-risk patients were those with at least one univariate risk factor. They are Stage II patients with T2bN0 and T2bN1 categories and Stage III patients with T2bN2 and T3N0-2 categories. The risk of recurrence is modest (18%). High-risk patients have risk factors by multivariate analysis. They are stage T4 or N3 patients. Their risk of recurrence is high (36%). CONCLUSION: Low-risk patients have an excellent outcome. Future trials should focus on reducing treatment-associated toxicities and complications and reevaluate the benefit of sequential adjuvant chemotherapy. The recurrence in treatment of intermediate-risk patients is modest; CCRT and adjuvant chemotherapy may be the best standard for them. Patients with T4 and N3 disease have poorer prognosis. Hyperfractionated radiotherapy may be considered for the T4 patients. Future study in these high-risk patients should also address the problem of distant spread of the disease.

Adult↗
PubMed2000

Long-term survival of nasopharyngeal carcinoma following concomitant radiotherapy and chemotherapy.

PURPOSE: The purpose of this study is to demonstrate long-term survival of nasopharyngeal carcinoma treated with concomitant chemotherapy and radiotherapy (CCRT) followed by adjuvant chemotherapy. METHODS AND PATIENTS: One hundred and seven patients with Stage III and IV (American Joint Committee on Cancer, AJCC, 1988) nasopharyngeal carcinoma (NPC) were treated with concomitant chemotherapy and radiotherapy (CCRT) followed by adjuvant chemotherapy between April 1990 and December 1997 in Koo Foundation Sun Yat-Sen Cancer Center, Taipei. The dose of radiation was 70 Gray (Gy) given in 35 fractions, 5 fractions per week. Two courses of chemotherapy, consisting of cisplatin and 5-fluorouracil, were delivered simultaneously with radiotherapy in Weeks 1 and 6 and two additional monthly courses were given after radiotherapy. According to the AJCC 1997 staging system, 32 patients had Stage II disease, 44 had Stage III, and 31 had Stage IV disease. RESULTS: With median follow-up of 44 months, the 5-year overall survival rate in all 107 patients was 84.1%, disease-free survival rate was 74.4%, and locoregional control rate was 89.8%. The 3-year overall survival for Stage II was 100%, for Stage III it was 92.8%, and for Stage IV, 69. 4% (p = 0.0002). The 3-year disease-free survival for Stage II was 96.9%, for Stage III it was 87.7%, and for Stage IV it was 51.9% (p = 0.0001). CONCLUSION: CCRT and adjuvant chemotherapy is effective in Taiwanese patients with advanced NPC. The prognosis of AJCC 1997 Stage II and III disease is excellent, but, for Stage IV (M0), it is relatively poor. Future strategies of therapy should focus on high-risk AJCC 1997 Stage IV (M0) cohort.

Adult↗
PubMed2000

Local radiotherapy with or without transcatheter arterial chemoembolization for patients with unresectable hepatocellular carcinoma.

PURPOSE: To evaluate the treatment outcome, patterns of failure, and prognostic factors for patients with unresectable hepatocellular carcinoma (HCC) treated with local radiotherapy alone or as an adjunct to transcatheter arterial chemoembolization (TACE). METHODS AND MATERIALS: From March 1994 to December 1997, 25 patients with unresectable HCC underwent local radiotherapy to a portion of the liver. Twenty-three patients were classified as having cirrhosis in Child-Pugh class A and 2 in class B. Mean diameter of the treated hepatic tumor was 10.3 cm. Mean dose of radiation was 46.9 +/- 5.9 Gy in a daily fraction of 1.8-2 Gy. Sixteen patients were also treated with Lipiodol and chemotherapeutic agents mixed with Ivalon or Gelfoam particles for chemoembolization, either before and/or after radiotherapy. Percutaneous ethanol injection therapy (PEIT) was given to one patient. All patients were monitored for treatment-related toxicity and for survival and patterns of failure. RESULTS: In a median follow-up period of 23 months, 11 patients were alive and 14 dead. The median survival duration from treatment was 19.2 months with a 2-year survival of 41%. Only 3 of 25 patients had local progression of the treated hepatic tumor. The recurrences were seen within the liver or extrahepatic. The 2-year local, regional, and extrahepatic progression-free survival rates were 78%, 46%, and 39%, respectively. The local control ranked the highest. Patients with Okuda Stage I disease had significantly longer survival than those with Stage II and III (p = 0.02). Patients with T4 disease (p = 0.02) or treated with radiotherapy alone (p = 0.003) had significantly shorter survival. T4 disease (p = 0.03) and pretreatment alpha-fetoprotein level of more than 200 ng/ml (p = 0. 03) were associated with significantly worse regional progression-free survival. A significant difference was observed in both regional progression-free survival (p = 0.0001) and extrahepatic progression-free survival (p = 0.005) between patients with and without portal vein thrombosis before treatment. The presence of satellite nodules had a significantly worse impact on regional progression-free survival (p = 0.04) and extrahepatic progression-free survival (p = 0.03). Patients with hepatic tumor more than 6 cm in diameter or portal vein thrombosis tended to have shorter survival. Radiation-induced liver disease (RILD) and gastrointestinal bleeding were the most common treatment-related toxicities. CONCLUSION: Radiotherapy is effective in the treatment of patients with unresectable HCC. Its effect appeared to be more prominent within the site to which radiation was given. The combination of TACE and radiation was associated with better control of HCC than radiation given alone, probably due to the selection of patients with favorable prognosis for the combined treatment. A dose-volume model should be established in the next phase of research in the treatment of unresectable HCC.

Adult↗
PubMed2000

Unique features of breast cancer in Taiwan.

Between April 1990 and December 1997, 811 consecutive patients with 830 newly diagnosed breast cancers having their primary treatments in our institution were included in this study. Sixty three percent of breast cancer patients were premenopausal. The early-onset breast cancer (age < or = 40) composed 29.3% of all patients. The five-year survival rate of all patients was 80.4% (95% confidence interval [CI], 76.2-84.6%). The five-year overall survival rate for stage 0 was 95.7% (95% CI, 87.3-100%), stage I, 93.9% (95% CI, 88.9-98.9%), stage II, 88.5% (95% CI, 82.0-95.1%), stage III, 65.0% (95% CI, 54.0-75.9%), and stage IV, 18.5% (95% CI, 3.4-33.7%). Multivariate analysis of primary operable breast cancer revealed that axillary lymph node involvement, high nuclear grade and early-onset breast cancer (age < or = 40) were poor prognostic factors. The early-onset breast cancer had a more aggressive clinical behavior than that of the older age group, their five-year disease-free survival rates for stage I, stage II and stage III diseases being only 64.7%, 66.5%, and 43.3%, respectively. In these patients the only meaningful prognostic factor was extensive axillary lymph node metastasis (> or = 10). In summary, breast cancer patients in Taiwan tend to be younger than their counterpart in western countries. The early-onset breast cancer had poorer prognostic features for all stages comparing to the older age group. Standard pathologic factors are not good predictors of their outcome. For these patients new biologic markers need to be sought to distinguish between high and low risk and the treatment strategy for them should be guided by the aggressive characteristics of the disease.

Adult↗
PubMed2000

Adjuvant sequential chemotherapy with doxorubicin plus cyclophosphamide, methotrexate, and fluorouracil (ACMF) with concurrent radiotherapy in resectable advanced breast cancer.

Doxorubicin (Adriamycin) is an anthracycline effective in breast cancer. Despite a worldwide acceptance of Adriamycin in the adjuvant chemotherapy to maximize the survival benefit in the higher risk patients with breast cancer with promising results, oncologists in general do not favorably consider anthracyclines in the adjuvant treatment setting because of concern about the acute and chronic drug-related toxicity. For high-risk patients with breast cancer with more than three positive axillary lymph nodes, this series adopted a modified sequential regimen of ACMF first with Adriamycin (A) as a single agent in 3-weekly administration for three courses, and then a combination of cyclophosphamide, methotrexate, fluorouracil (CMF) every 3 to 4 weeks for six courses given in an outpatient setting concurrent with radiation therapy as an adjuvant treatment. A total of 56 patients underwent modified radical mastectomy and 3 others breast conservation surgery for their invasive breast cancer. Forty-seven (84%) patients completed the intended adjuvant treatment and 1 patient died of infection from treatment-related neutropenia. As a whole, the 3-year overall survival and disease-free survival rates of 56 patients analyzed were 82.3% and 64.4%, respectively. In this high-risk group, patients with four to nine positive nodes showed a slightly better trend of survival than those with 10 or more positive nodes without reaching statistically significant difference (36-month overall survival: 90.9% vs. 72.5%, p = 0.06; disease-free survival: 78.7% vs. 47.8%, p = 0.38). In this entire group of patients, locoregional recurrence was absent. A total of 55 episodes of grade III and IV hematologic toxicity were observed, with only one death from neutropenic sepsis. This modified ACMF regimen offers a good survival rate in breast cancer patients with more than three positive axillary lymph nodes. When these patients are carefully managed, the morbidity and mortality related to the treatment are low.

Adult↗
PubMed2000

Concomitant radiotherapy and chemotherapy for early-stage nasopharyngeal carcinoma.

PURPOSE: Early-stage nasopharyngeal carcinoma (NPC) continues to carry a failure rate of 15% to 30% when treated with radiotherapy alone; the benefit of concomitant radiotherapy and chemotherapy (CCRT) in early-stage NPC is unclear. The purpose of this report is to describe our efforts to improve treatment outcome in early-stage NPC after CCRT. PATIENTS AND METHODS: Of 189 newly diagnosed NPC patients without evidence of distant metastases who were treated in our institution between 1990 and 1997, 44 presented with early-stage (stage I and II) disease according to the American Joint Committee on Cancer (AJCC) 1997 NPC staging system. Twelve of these patients were treated with radiotherapy alone and 32 with CCRT. Each patient's head and neck area was evaluated by magnetic resonance imaging or computed tomography. Radiotherapy was administered at 2 Gy per fraction per day, Monday through Friday, for 35 fractions for a total dose of 70 Gy. Chemotherapy consisting of cis-diamine-dichloroplatinum and fluorouracil was delivered simultaneously with radiotherapy in weeks 1 and 6 and sequentially for two monthly cycles after radiotherapy. RESULTS: Patients who were treated with radiotherapy alone primarily had stage I disease, whereas none of those who were treated with CCRT had stage I disease (11 of 12 patients v none of 32 patients; P =.001). The locoregional control rate at 3 years for the radiotherapy group was 91.7% (median follow-up period, 34 months) and was 100% for the CCRT group (median follow-up period, 44 months) (P =.10). The 3-year disease-free survival rate in the radiotherapy group was 91.7% and was 96.9% in the CCRT group (P =.66). CONCLUSION: Our results reveal excellent prognosis of AJCC 1997 stage II NPC treated with CCRT. Stage II patients with a greater tumor burden treated with CCRT showed an equal disease-free survival, compared with stage I patients treated with radiotherapy alone. A prospective randomized trial is underway to confirm the role of CCRT in stage II NPC.

Adult↗
PubMed1999

A pilot study of three-dimensional conformal radiotherapy in unresectable hepatocellular carcinoma.

BACKGROUND: The purpose of this study was to determine the potential role of three-dimensional (3-D) conformal radiotherapy (RT) in treatment of unresectable hepatocellular carcinoma (HCC). METHODS: Thirteen patients were included in this study, which was conducted between 1993 and 1996. Nine patients (group A) were treated with 3-D conformal RT alone because of main portal vein thrombosis, inferior vena cava thrombosis, obstructive jaundice and failure of previous transcatheter arterial chemoembolization (TACE) to control the disease. The remaining four patients (group B) were treated with a combination of TACE and 3-D conformal RT. RESULTS: The greatest dimension of the main tumour in the whole group of patients ranged from 6 to 25 cm (median 15 cm). The radiation dose ranged from 40 to 60 Gy. The tumour response was evaluated by computed tomography scans of the liver 6-8 weeks after completion of radiotherapy. Partial response was observed in 58% of the patients (seven of 12) and minimal response in another 25% of patients (three of 12). One patient could not be evaluated because of the development of hepatic failure 1 month after completion of RT. All patients in group B lived for more than 1 year (range 16-40 months). In group A, one patient who had a large tumour (11 x 10 x 21 cm) with portal vein thrombosis was converted to become resectable after 45 Gy of radiation. The resection specimen revealed no residual cancer cells. This patient is alive longer than 15 months after treatment without the evidence of disease. CONCLUSIONS: Our experience indicates that HCC is more radiosensitive than it was traditionally expected. Three-dimensional reconstruction of tumour and surrounding organs helps to avoid excessive exposure of the liver and adjacent organs to RT and makes it a safer treatment modality for unresectable HCC. Our preliminary data show promise and are worthy of further study to explore the potential role of radiotherapy in the treatment strategy for HCC at various stages of involvement.

Aged↗
PubMed1998

Prognostic features and treatment outcome in locoregionally advanced nasopharyngeal carcinoma following concurrent chemotherapy and radiotherapy.

PURPOSE: Concurrent chemotherapy and radiotherapy (CCRT) are effective in treatment of locoregionally advanced nasopharyngeal carcinoma (NPC). However, the prognostic factors after CCRT have not been evaluated. We therefore attempt to evaluate factors that influence treatment outcomes following CCRT. METHODS AND MATERIALS: Seventy-four (5 in stage III and 69 in stage IV) patients with locoregionally advanced NPC were treated with CCRT. Radiotherapy was delivered either at 2 Gray (Gy) per fraction per day up to 70 Gy or 1.2 Gy, 2 fractions per day, up to 74.4 Gy. Concurrent chemotherapy consisted of cisplatin and 5-fluorouracil. Cox proportional-hazards model was used to analyze the prognostic factors which included age, gender, pathologic type, T, N, lactate dehydrogenase (LDH), and infiltration of the clivus. RESULTS: The primary tumor control rate at 3 years was 96.7% (95% confidence interval [CI]: 92.5-100), distant metastasis-free survival 81.1% (95% CI: 70.6-91.6), disease-free survival 77.0% (95% CI: 65.3-88.7), and overall survival 79.8% (95% CI: 69.2-90.4) with a median follow-up interval of 29 months (range 15-74 months). Cox proportional-hazards model revealed that infiltration of the clivus and serum level of LDH before treatment were the most two important factors that predict distant metastases. Infiltration of the clivus and the serum LDH level greater than 410 U/L were strongly associated with distant metastasis-free survival (p = 0.0004 and p = 0.0002, respectively). When these two risk factors were considered together, no distant metastasis was observed in 40 patients with both intact clivus and LDH < or = 410 U/L. On the contrary, 13 of the remaining 34 patients with at least one risk factor developed distant metastasis (p = 0.0001). CONCLUSION: Our study demonstrates that CCRT can improve the primary tumor control of 96.7% and disease-free survival of 77.0% at 3-year follow-up. Distant metastasis, however, is the major cause of failure. Infiltration of the clivus by the tumor and LDH greater than 410 U/L are the two independent and useful prognostic factors in patients with locoregionally advanced NPC who were treated with CCRT. Good- and poor-risk patients can be distinguished by virtue of their having both conditions.

Adult↗
PubMed1998

Hyperfractionated irradiation with or without concurrent chemotherapy for locally advanced head and neck cancer.

BACKGROUND: Radiotherapy is often the primary treatment for advanced head and neck cancer, but the rates of locoregional recurrence are high and survival is poor. We investigated whether hyperfractionated irradiation plus concurrent chemotherapy (combined treatment) is superior to hyperfractionated irradiation alone. METHODS: Patients with advanced head and neck cancer who were treated only with hyperfractionated irradiation received 125 cGy twice daily, for a total of 7500 cGy. Patients in the combined-treatment group received 125 cGy twice daily, for a total of 7000 cGy, and five days of treatment with 12 mg of cisplatin per square meter of body-surface area per day and 600 mg of fluorouracil per square meter per day during weeks 1 and 6 of irradiation. Two cycles of cisplatin and fluorouracil were given to most patients after the completion of radiotherapy. RESULTS: Of 122 patients who underwent randomization, 116 were included in the analysis. Most patients in both treatment groups had unresectable disease. The median follow-up was 41 months (range, 19 to 86). At three years the rate of overall survival was 55 percent in the combined-therapy group and 34 percent in the hyperfractionation group (P=0.07). The relapse-free survival rate was higher in the combined-treatment group (61 percent vs. 41 percent, P=0.08). The rate of locoregional control of disease at three years was 70 percent in the combined-treatment group and 44 percent in the hyperfractionation group (P=0.01). Confluent mucositis developed in 77 percent and 75 percent of the two groups, respectively. Severe complications occurred in three patients in the hyperfractionation group and five patients in the combined-treatment group. CONCLUSIONS: Combined treatment for advanced head and neck cancer is more efficacious and not more toxic than hyperfractionated irradiation alone.

Aged↗
PubMed1998

Diagnostic thoracic-computed tomography in radiotherapy for loco-regional recurrent breast carcinoma.

PURPOSE: This study was initiated to evaluate whether pretreatment diagnostic thoracic CT scan was useful for patients with loco-regional recurrent breast carcinoma, and to assess its impact on the design of radiotherapeutic treatment. METHODS AND MATERIALS: Between March 1991 and January 1997, 44 patients underwent thoracic CT examination with contrast material before the consideration of radiotherapy for their isolated loco-regional recurrent breast carcinoma. The CT radiographs were prospectively reviewed for additional findings clinically undetected by prior physical examination and plain-chest radiograph. The changes made in treatment design and dosage of radiation as a result of CT findings were recorded for analysis. The correlation between prognostic indicators and the CT findings was also studied. RESULTS: Twenty-two of 44 (50%) patients were found to have additional abnormalities detected only after thoracic CT examinations were performed. The strategy of radiation therapy was altered in 17 of 22 (77%) patients as a result. Patients with shorter disease-free interval (p = 0.08) and multiple sites of recurrence (p = 0.05) tended to have greater numbers of findings on CT scan previously unsuspected. Thus, CT scan is a valuable guide to treating loco-regional recurrent disease. CONCLUSION: Pretreatment diagnostic thoracic CT scan offers essential information that can alter treatment planning and thus optimize treatment strategy for a large proportion of patients with clinically isolated loco-regional recurrent breast carcinoma. In this population of patients we recommend that thoracic CT examination be considered before the initiation of radiation therapy.

Breast Neoplasms↗
PubMed1998

T classification and clivus margin as risk factors for determining locoregional control by radiotherapy of nasopharyngeal carcinoma.

BACKGROUND: The purpose of this study was to determine risk factors that affect locoregional control of nasopharyngeal carcinoma (NPC) after radiotherapy. Computed tomography (CT) is utilized for radiotherapy planning and for identifying high risk anatomic areas. METHODS: Between April 1990 and December 1993, 40 consecutive patients (1 in Stage I, 3 in Stage II, 5 in Stage III, and 31 in Stage IV) who had locoregional NPC were given definitive radiotherapy at the Koo Foundation Sun Yat-Sen Cancer Center in Taipei, Taiwan. All patients had individualized CT treatment planning. The dimension of each tumor as shown on the treatment planning CT were mapped on conventional simulation films. The extent of each tumor was further affirmed by magnetic resonance imaging (MRI) and the tumor map revised as necessary. The primary radiation fields were designed to include the primary tumor and potential spread areas with appropriate margins. Concurrent chemotherapy was also given to 35 patients (87.5%) who had positive cervical lymph nodes or primary tumors extending beyond the nasopharynx. RESULTS: By the end of December 1995, after a median follow-up of 42 months and minimal follow-up of 24 months, the locoregional control rate at 4 years was 84.8% (95% confidence interval [CI], 72.3-97.3), disease free survival 68.4% (95% CI, 52. 1-84.7), and overall survival 76.7% (95% CI, 63.4-90.0). The radiation field margin near the sphenoid sinus averaged 1.9 cm, the clivus margin 1.1 cm, the pterygoid fossa margin 2.0 cm, and the oral cavity margin 1.7 cm. Risk factor analysis revealed that T classification and the radiation field margin at the clivus were the most important factors for locoregional control of the tumor. The locoregional control rates were 92.6% (25/27) for T1-T3 patients and 76.9% (10/13) for T4 patients (P = 0.03). The locoregional control rates were 71.4% (5/7) for patients with a clivus margin < 1 cm and 90.6% (29/32) for patients with a clivus margin > or = 1 cm (P = 0.08). CONCLUSIONS: The excellent locoregional control observed in this series may be attributed to the concurrent chemotherapy and radiotherapy as well as meticulous treatment planning with CT and MRI. The precise delineation of the involved area with the aid of CT, which is taken while the patient is in the position for irradiation, serves to define the necessary safety margin of the radiation field. T classification and clivus margin are the most important factors in determining locoregional control of radiotherapy of NPC. The statistical trend observed in this study indicated that the clivus margin should be adequate to reduce the failure around the clivus, as all local recurrences were observed in this area.

Adult↗
PubMed1998

Preoperative concurrent chemotherapy and radiotherapy in rectal cancer patients.

The management of rectal cancer has changed significantly in recent years. The key end-point is no longer survival but rather preservation of sphincter function with improved quality of life. Preoperative radiation can not only render a low-lying rectal tumor amenable to sphincter-preserving surgery but has also been reported to give better local control and lower toxicity than postoperative radiotherapy. From October 1991 through July 1996, 46 patients with local advanced or low-lying rectal cancer were treated with preoperative high-dose radiotherapy and concurrent chemotherapy. All patients underwent pelvic radiotherapy with 5,000 to 5,400 cGy in 25 to 27 fractions. Chemotherapy was given concomitantly and consisted of two courses of 5-fluorouracil (5-FU) at 1,000 mg/m2 for 4 days in week 1 and week 5 plus mitomycin C 10 mg/m2 single bolus on day 1 of week 1. In 30 patients, postoperative adjuvant chemotherapy with 5-FU and levamisole weekly was also given, for a total of 12 months. The most common acute toxicity was grade 1 to 2 diarrhea and tenesmus during radiation or soon afterward. Only five of the 46 patients experienced symptomatic grade 3 acute toxicity. Forty-two patients underwent subsequent surgery 6 to 8 weeks after concurrent chemoradiotherapy. Pathologic examination disclosed complete tumor regression in eight patients and microscopic residual disease in 13 patients after preoperative chemoradiation. Of the 42 patients who completed the intended treatments, only one had local recurrence. The sphincter was preserved in 21 of the 26 patients in whom the tumor was located within 5 cm above the anal verge. Twelve of the 16 evaluable patients had good to excellent sphincter function. The 2-year overall survival rate was 93% and the disease-free survival was 81%. Our findings indicate that preoperative concurrent chemoradiotherapy not only allows low-lying rectal tumors to be resected while preserving sphincter function but also results in good local control and acceptable toxicity.

Adenocarcinoma↗
PubMed1994

Oral ondansetron pharmacokinetics: the effect of chemotherapy.

The effect of a typical 5-day chemotherapy treatment with cisplatin (20-40 mg/m2 per day) and 5-fluorouracil (5-FU, 1 gm/m2 per day) on the pharmacokinetics of ondansetron was investigated. Twenty cancer patients received 8 mg of ondansetron in three periods, including an oral tablet on day 1, an intravenous infusion on day 4, and an oral tablet on day 5. Absolute bioavailability after the oral dosing on day 1 was 87.5 +/- 31.3%, and on day 5 was 85.2 +/- 22.1% (P > .05). Mean values of AUC, Cmax, Tmax, and half life on days 1 and 5 were 399 +/- 275 and 381 +/- 222 ng.hour/mL, 53.3 +/- 26.8 and 43.6 +/- 21.7 ng/mL, 1.9 +/- 1.4 and 2 +/- 1.4 hours, and 5.21 +/- 1.78 and 6.19 +/- 1.99 hours, respectively. These values were not significantly different (P > .05). In summary, this study showed that cisplatin and 5-FU did not significantly alter the pharmacokinetics of oral ondansetron in cancer patients during the 5 days of chemotherapy. Oral bioavailability of ondansetron appeared to be greater in cancer patients than in healthy subjects.

Administration, Oral↗
PubMed1994

The role of CD45RO in antithymocyte globulin's stimulation of primitive haemopoietic cells.

We have found that antithymocyte globulin (ATG), an equine antibody with proven efficacy in aplastic anaemia (AA), has a direct stimulatory effect on primitive haemopoietic cells from normal donors. This growth stimulation may be mediated via anti-CD45RO activity present in the ATG preparation. Addition of unabsorbed ATG enhanced colony growth at 21 d in the blast colony forming cell (Bl-CFC) assay. Prior absorption of ATG by incubation with the CD45RO+ MOLT-4 cell line resulted in the loss of enhancement. Absorption by MOLT-4 cells preincubated with anti-CD45RO mAb, UCHL-1, restored ATG's stimulatory effect. The Bl-CFC could also be stimulated to grow by the addition of UCHL-1 directly. Incubation of the primitive haemopoietic cells for 4 h with ATG was associated with a decline in the antigenic density of CD45RO, a tyrosine phosphatase. This down-regulation may upset the balance between growth factor-induced tyrosine kinase activation and tyrosine phosphate dephosphorylation resulting in increased growth of primitive cells, a possible factor in the sustained recovery of haemopoiesis seen in AA patients after ATG treatment.

Anemia, Aplastic↗
PubMed1993

Cancer epidemiology in the Far East--contrast with the United States.

Cancer incidence is rising rapidly in the Far East. Liver and lung cancers are the dominant neoplasms, but the incidence of breast and colorectal cancers has been increasing over the past 30 years, as Asians gradually adopt Western diet and lifestyle. Over the same period, the incidence of gastric cancer declined, although it remains a major health problem in many Asian countries. Malignancies presumed to be virus associated, such as liver cancer, nasopharyngeal cancer, cervical cancer, and adult T-cell leukemia, are far more common in Asia than in the United States and other parts of the world. Preventive measures, such as hepatitis B immunization to prevent liver cancer, may prove effective for some of these malignancies in the years to come. Meanwhile, cancers that are related to smoking and diet, such as, cancer of the lung, breast, and colorectum, will become increasingly common in the Far East.

Asia, Eastern↗