Search PubMed⌕ Search

Biomedical subjects

J D Cox

Publications and source records attributed to J D Cox.

At least 145 records · Page 8Linked to original sources
PubMed1990

A randomized phase I/II trial of hyperfractionated radiation therapy with total doses of 60.0 Gy to 79.2 Gy: possible survival benefit with greater than or equal to 69.6 Gy in favorable patients with Radiation Therapy Oncology Group stage III non-small-cell lung carcinoma: report of Radiation Therapy Oncology Group 83-11.

A phase Ilate/II trial of hyperfractionated (HFX) radiation therapy for non-small-cell carcinoma of the lung (NSCCL) was conducted by the Radiation Therapy Oncology Group (RTOG) between 1983 and 1987. Fractions of 1.2 Gy were administered twice daily with greater than or equal to 4 hours between fractions. Patients were randomized to receive minimum total doses of 60.0, 64.8, and 69.6 Gy. After acceptable risks of acute and late effects were found, 74.4 Gy and 79.2 Gy arms were added, and the lowest total dose arms were closed. No significant differences in the risks of acute or late effects in normal tissues were found among the 848 patients analyzed in the five arms; risks of severe or life-threatening pneumonitis were 2.6% for 60.0 to 64.8 Gy, 5.7% for 69.6 to 74.4 Gy, and 8.1% for 79.2 Gy. Among 350 patients who had the same criteria as Cancer and Leukemia Group B (CALGB) protocol 84-33 (American Joint Committee on Cancer Staging [AJCCS], 1984, stage III; Karnofsky performance status [KPS] 70 to 100; less than 6% weight loss), there was a dose response for survival: survival with 69.6 Gy (median, 13.0 months; 2 years, 29%) was significantly (P = .02) better than the lower total doses. There were no differences in survival among the three highest total-dose arms. Comparisons with results in similar patients treated with 60 Gy in 30 fractions of 2.0 Gy 5 days per week for 6 weeks suggest benefit from HFX radiation therapy with 69.6 Gy. Improvement in survival with HFX radiation therapy at 69.6 Gy total dose without increase in normal tissue effects, justifies phase III comparison with standard fractionation alone and combined with systemic chemotherapy in this common presentation of NSCCL.

Adult↗
PubMed1989

Second malignancies in patients who have head and neck cancer: incidence, effect on survival and implications based on the RTOG experience.

The development of second malignant tumors (SMTs), in patients who have had their first tumor treated successfully, represents a serious limitation of current therapeutic strategies for head and neck cancers. To improve our understanding of the current magnitude of the problem and the various factors that might influence its importance, we reviewed the Radiation Therapy Oncology Group's (RTOG) prospectively collected registry of all head and neck patients seen in participating member institutions between February 1977 and April 1980. A total of 928 patients were identified who had squamous cell carcinomas of the head and neck region, no prior or coincident history of another malignant tumor, and whose planned treatment consisted of radiation therapy only. A total of 110 second, independent, malignant tumors occurred in these patients. Overall, the estimated risk of developing a second tumor within 3 years of radiotherapy was 10%, within 5 years 15%, and within 8 years 23%. Minor differences in frequency were observed for different primary sites. These SMTs unquestionably influenced subsequent survival adversely. Analysis of the database also revealed that the extent of the primary tumor influenced the risk of a second; most occurred in patients who presented with the smallest primary tumors because of their better survival. Our data indicate that preventive medicine should have its greatest impact in those patients who are treated for an early stage primary tumor.

Carcinoma, Bronchogenic↗
PubMed1989

Radiation oncology: postgraduate medical education in the United States, 1988.

The fourteenth survey of postgraduate medical education in radiation oncology in the United States was conducted in the first three months of 1988. It revealed stability in the number of approved programs, positions offered, and physicians in training compared with 1986. The proportion of trainees who were U.S. citizens by birth rose to an all-time high of 88%, and the proportion of foreign medical graduates decreased to 9%. The proportion of women in residency has remained unchanged (24%) over the past 6 years. At present, approximately 150 physicians complete residency and enter practice each year, one-third of whom commence in an academic setting. A high proportion of recent graduates of approved programs successfully completes the examinations and becomes certified by the American Board of Radiology.

Certification↗
PubMed1988

Mammary carcinoma developing after radiotherapy and chemotherapy for Hodgkin's disease.

Two patients developed breast cancer after treatment of Hodgkin's disease. Both had received mediastinal irradiation 13 to 15 years, respectively, before the diagnosis of breast carcinoma. One patient had synchronous bilateral breast cancer when the diagnosis was made. Discussed is the risk of mammary carcinoma as a second malignant neoplasm in patients treated for Hodgkin's disease.

Adult↗
PubMed1988

Tolerance of pelvic normal tissues to hyperfractionated radiation therapy: results of Protocol 83-08 of the Radiation Therapy Oncology Group.

A prospective, centrally randomized Phase I/II trial of hyperfractionation in definitive radiation therapy for locally advanced squamous and transitional cell carcinoma of the bladder was conducted by the Radiation Therapy Oncology Group (RTOG) from April 1983 through June 1986. Patients with T3-4 and T2 N+ (AJC) histologically-confirmed cancer of the bladder received twice daily radiation therapy with 1.2 Gy per fraction and a minimum of 4 hr between fractions. All patients received a whole pelvic total dose of 50.4 Gy: Total doses to reduced volumes were 60.0 Gy, 64.8 Gy, or 69.6 Gy. Of 54 patients entered, 50 were eligible. An unbalanced treatment assignment was used: Nine patients received 60.0 Gy, 15 patients received 64.8 Gy and 26 received 69.6 Gy. Performance status (Karnofsky) was 90-100 in 72% of patients and 92% had transitional carcinoma. Eighty percent of tumors were T3 or T4. Observation of at least 18 months was available for 26 patients. Grade 3 acute reactions (within 90 days) were reported in eight patients (one at 60.0 Gy, three at 64.8 Gy and four at 69.6 Gy). Five patients experienced a total of seven major late effects--four Grade 3 and three Grade 4. The cumulative probability of Grade 3 and 4 late complications of treatment for the 46 patients at risk for late complications was 5% +/- 3% at 6 months, 7% +/- 4% at 12 months, and 10% +/- 5% at 18 and 24 months. The cumulative probability of Grade 3 or 4 late complications for patients who received a total dose of 69.6 Gy was 5% +/- 4% at 6 and 12 months and 11% +/- 8% at 18 and 24 months. Only one patient who experienced major late effects was also reported to have major acute reactions. Comparisons of survival of patients treated in the current study with those who received 60 Gy in 30 fractions in 6 weeks in RTOG Protocol 71-04, did not suggest any deleterious effects from hyperfractionated radiation therapy to the pelvis. The normal pelvic tissues tolerated hyperfractionated radiation therapy sufficiently well to justify exploring it, alone and with brachytherapy, in other pelvic tumors.

Aged↗
PubMed1988

Phase I-II study of prophylactic hepatic irradiation with local irradiation and systemic chemotherapy for adenocarcinoma of the pancreas.

Although the addition of 5-FU to radiation therapy for locally advanced adenocarcinoma of the pancreas improved short-term survival (GITSG), there were no differences in patterns of failure. Hepatic metastases were equally common in both groups. Therefore, a pilot study of prophylactic hepatic irradiation was developed. Between March 1983 and May 1985, 16 patients were entered in a Phase I/II study of prophylactic hepatic irradiation with local irradiation and systemic chemotherapy for adenocarcinoma of the pancreas at the Medical College of Wisconsin Affiliated Hospitals. Megavoltage radiation (1.8 Gy/fraction) was given to the pancreas with a minimal margin (2 cm) around the tumor, localized by surgical clips or CT scan with a total dose of 61.2 Gy over 7 weeks. Prophylactic hepatic irradiation was added to the fourth week of irradiation to a total dose of 23.4 Gy over 21/2 weeks. 5-Fluorouracil, 500 mg/M2/day was given at Day 1, 2, 3, 29, 30, and 31 of radiotherapy, then a weekly maintenance for 1 year. Fifteen patients were evaluable: One patient refused chemotherapy. The follow-up period was 14 to 50 months (median 26 months). The most common side effect was nausea. Maintenance 5-FU was discontinued in one patient because of GI bleeding. Three-quarters of the patients developed temporary elevations of hepatic enzymes. No severe or life-threatening complications were observed. One, 2-, 3-, and 4-year disease-free survivals are 66.7%, 46.7%, 20% and 13.3%, respectively. Patterns of failure revealed that only two patients had hepatic metastasis as the first site of failure, five patients died of abdominal carcinomatosis, and three patients failed in the pancreas. Two patients died without evidence of cancer. Two patients are alive and well beyond 4 years after the diagnosis. This study confirms that such aggressive combined modality treatment is well tolerated and suggests that the frequency of hepatic metastasis can be reduced.

Adenocarcinoma↗
PubMed1988

Total dose, fraction size, and tumor volume in the local control of Hodgkin's disease.

There are important uncertainties in the radiation therapy of Hodgkin's disease. These uncertainties are related to dose-fractionation and total dose necessary to control subclinical disease (prophylactic irradiation), small-size tumors, and especially bulky tumors such as those frequently encountered in the mediastinum. Data are lacking on total dose and tumor control as a function of tumor volume. A retrospective study was undertaken of patients with Hodgkin's disease Stages I-III treated with radiation therapy alone at the Medical College of Wisconsin Affiliated Hospitals between 1970 and 1982. Detailed dose calculations of off-axis points were made to assign precise minimum doses to 1,304 separate lymph node regions. Treatment volumes received individual fractions of 150 cGy to 300 cGy and total doses of 30 Gy to 42 Gy. Tumor control was correlated with tumor size at presentation, fractionation schedule, and total dose. The results confirm the absence of a dose-response relationship for tumor control, between 30 Gy and 42 Gy total dose. In addition, there is no apparent difference in total dose required for larger tumors relative to that required for small tumors.

Adolescent↗
PubMed1988

Acute radiation effects on cutaneous microvasculature: evaluation with a laser Doppler perfusion monitor.

Laser Doppler perfusion monitoring is a noninvasive technique for measuring blood flow in epidermal microvasculature that makes use of the frequency shift of light reflected from red blood cells. Measurements in patients undergoing radiation therapy show increases in blood flow of ten to 25 times baseline at doses above 50 Gy, and increases are observed with doses as low as 2 Gy. Follow-up measurements show rapid decreases in flow levels after completion of therapy, but levels remain elevated even at 1 year.

Blood Flow Velocity↗
PubMed1988

International Clinical Trials in Radiation Oncology. Lung sites.

The lung studies of the RTOG have been among the most productive of any in the group. The development of studies has been predicated upon failure pattern analyses from previous trials. Multiple approaches to attacking these diseases have been taken, including dose/fraction studies and high LET irradiations to improve local-regional control, prophylactic irradiation of sites of frequent, distant metastases, systemic chemotherapy and radioimmunoglobulins to control distant metastases, and biologic response modifiers to restore or enhance host defense mechanisms. All studies have been predicated upon making incremental advances in improving treatment outcome in these common disease, based on the philosophy that small improvements in survival will save thousands of lives.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1987

Brain metastasis in patients with superior sulcus tumors.

During a 20-year period, from 1963 to 1983, 68 patients were treated for carcinoma of the lung presenting in the superior sulcus. Their ages ranged from 41 to 79 years (median, 56 years). Thirty-six patients had squamous cell carcinoma, 13 had adenocarcinoma, 14 had large cell carcinoma, two had small cell carcinoma, and three had clinical diagnosis only. All tumors were considered to be inoperable or unresectable and were treated with external irradiation alone. The 3-year disease-free survival was 25%. Brain metastasis developed in 23 patients (34%); the brain was the first site of metastasis in 16 patients (24%), five of whom eventually developed other sites of metastasis. The cumulative probability of brain metastasis was 53% at 3 years. Brain metastases were seen in ten patients (28%) with squamous cell carcinoma, five patients (38%) with adenocarcinoma, seven patients (50%) with large cell carcinoma, and one patient without a histocytologic diagnosis. The proportion of patients younger than 60 years (19/41, 46%) who developed brain metastasis was significantly greater than that for patients 60 years or older (4/27, 15%) (P less than or equal to 0.01). Nine of 11 patients with metastasis only to the brain died as a consequence of the intracranial disease 1 to 13 months (median, 6 months) after the diagnosis of brain metastases. The other two patients received therapeutic irradiation to the entire brain and survived longer than 5 days after the whole-brain irradiation: one died at 62 months of intercurrent disease, and the other is alive and well 129 months after diagnosis. The high probability of brain metastasis from superior sulcus tumors, regardless of histopathologic type and the frequency with which the brain is the only site of clinical failure, suggest that systematic prophylactic cranial irradiation could reduce the morbidity and perhaps even contribute favorably to the survival of these patients.

Adult↗
PubMed1987

Cisplatin and fluorouracil as neoadjuvant therapy in head and neck cancer. A preliminary report.

A randomized, prospective trial utilizing cisplatin and fluorouracil as neoadjuvant chemotherapy in the treatment of advanced squamous cell carcinomas of the upper aerodigestive tract was initiated in January 1983. Sixty patients were stratified by site (oral cavity, 19; larynx, 14; hypopharynx, 14; oropharynx, 11; nasopharynx, one; and paranasal sinuses, one) and by stage (III, 19; IV, 41), and then randomized to receive either standard treatment (defined as preoperative irradiation followed by radical excision or irradiation alone) or adjuvant chemotherapy followed by standard treatment. An additional three patients were entered into the study, but withdrew. Chemotherapy consisted of three cycles for those patients in whom an objective tumor response was observed; nonresponders received standard treatment. Response to chemotherapy was complete in five and partial (greater than 50%) in 18 patients, for an overall response rate of 85%. The follow-up for surviving patients was a minimum of 24 months and a maximum of 44 months. Survival was compared for patients in both treatment groups according to the method of Lee and Desu. Despite excellent tumor response, actuarial survival was 70% in the standard treatment group as opposed to 56% in the experimental group. It was therefore evident that the high response rates reported in previous pilot studies do not necessarily result in improved survival in these cancers.

Carcinoma, Squamous Cell↗
PubMed1987

Postgraduate training in radiation oncology in the United States, 1986.

The thirteenth survey of training in Radiation Oncology in the United States, conducted in the first half of 1986, revealed a reduction in the number of approved programs, but little change in the number of positions offered. For the first time, every program had trainees, and every available training position was filled. The proportion of foreign exchange students in training fell from 52% 20 years ago, to 12% a decade later, to less than 1% at present. The proportion of foreign medical graduates fell from 29% in 1984 to 18% at present. The proportion of women in residency remained unchanged from 1982 and 1984. Approximately 150 physicians can be expected to complete training and enter the practice of radiation oncology each year for at least the next 4 years.

Directories as Topic↗