Biomedical subjects

S O Asbell

Publications and source records attributed to S O Asbell.

At least 19 recordsLinked to original sources

PubMed1995

Late effects of hyperfractionated radiotherapy for advanced head and neck cancer: long-term follow-up results of RTOG 83-13.

PURPOSE: The objective of this study was to examine the incidence of late effects of hyperfractionated radiotherapy for head and neck cancer as a function of the dose delivered, as well as the daily interfraction interval. In addition, we wished to examine the influence of other prognostic factors including age, gender, primary site, T- and N-stage, and overall stage on the late effects of hyperfractionated radiotherapy. METHODS AND MATERIALS: Between 1983 and 1987, 479 patients with advanced head and neck cancer were entered on a Phase ILE/II dose escalation trial of hyperfractionated radiotherapy. They were randomly assigned to receive a dose of 67.2, 72.0, 76.8, or 81.6 Gy, delivered at 1.2 Gy/fraction, twice a day (BID), 5 days/week. Of the 451 analyzable patients, 399 patients who received > or = 64.8 Gy and had a follow-up > 90 days were eligible for this study. Acute and late effects were scored with the RTOG/EORTC late radiation morbidity scoring scheme. For this analysis, patients were subclassified by the actual doses delivered and by an average daily interfraction interval of < or = 4.5 h or > 4.5 h. The incidence of late effects was estimated using a cumulative incidence approach. RESULTS: Fifty-nine patients received 67.2 +/- 2.4 Gy, 119 received 72.0 +/- 2.4 Gy, 98 received 76.8 +/- 2.4 Gy, and 123 received 81.6 +/- 2.4 Gy. The proportion of patients treated with a daily interfraction interval of > 4.5 h was 32, 50, 43, and 71%, respectively. The four treatment groups were well balanced with respect to pretreatment characteristics. The median follow-up was 1.71 years (range: 0.24-9.6) for all evaluable patients and 6.12 years for 85 alive patients. There was no significant difference in the incidence of late effects between the different dose levels. At 5 years, the cumulative incidence of late effects was 17, 14, 20, and 13% for grade 3, and 7, 3, 7, and 5% for grade 4. However, the incidence of late effects differed significantly with respect to daily interfraction interval. The cumulative incidence of grade 4 late effects increased from 6.3% at 2 years to 7.5% at 3 years to 8.0% at 4 years and 8.6% at 5 years with an interval of < or = 4.5 h, while it remained at a constant of 2.0% with an interval of > 4.5 h during the same period (p = 0.0036). Multivariate analysis showed that among the prognostic factors examined, daily interfraction interval of < or = 4.5 h was the only significant independent prognostic factor for the development of grade 3+ or grade 4 late effects (p = 0.0167 and p = 0.0013, respectively). CONCLUSION: Results of this randomized Phase ILE/II trial of hyperfractionated radiotherapy in head and neck cancer showed no apparent dose-response relationship for late effects within the range of 67.2-81.6 Gy. Daily interfraction interval was a significant independent factor for the development of late effects in a multivariate analysis.

Adult↗

PubMed1994

White matter changes are correlated significantly with radiation dose. Observations from a randomized dose-escalation trial for malignant glioma (Radiation Therapy Oncology Group 83-02).

BACKGROUND: A Phase I/II randomized dose-seeking trial was performed to document the severity, time course, and significance of white matter changes seen on serial imaging scans (magnetic resonance imaging, computed tomography) associated with bis-chlorethyl nitrosourea (BCNU) and hyperfractionated cranial irradiation. METHODS: Long term survivors (> or = 18 months) were identified from a prospective randomized dose-escalation Phase I/II trial designed to evaluate twice-daily radiotherapy for supratentorial high grade malignant gliomas. All scans were reviewed by a neuroradiologist who had no information about the prescribed dose and fractionation. In the trial, patients were assigned to receive 64.8 Gy, 72.0 Gy, 76.8 Gy, or 81.4 Gy (all fractionated as 1.2 Gy twice a day [bid]), or 48.0 Gy or 54.4 Gy (both in 1.6-Gy bid fractions). Bis-chlorethyl nitrosourea was administered every 8 weeks for 1 year. Of 747 randomized patients, 177 had analyzable scans. The scans reviewed were those acquired preoperatively, immediately postoperatively, 3, 6, 12, and 18 months after radiotherapy. Radiographic endpoints included no white matter change (Grade 0), minimal patchy white matter foci (Grade 1), start of confluence of white matter disease (Grade 2), large confluent areas (Grade 3), confluence with cortical/subcortical involvement (Grade 4), leukoencephalopathy (Grade 5), and possible necrosis (Grade 6) according to the classification of F. Fazekas et al. The effects were scored relative to the baseline preoperative scans. The dose pairs of 48 Gy and 54.4 Gy, 64.8 Gy and 72 Gy, and 76.8 Gy and 81.4 Gy were grouped together for analysis (low, intermediate, and high dose, respectively). Toxicity was analyzed in three ways: Grade 2 or worse, Grade 3 or worse, and Grade 6. RESULTS: Grade 2 or worse changes were observed in 26.6, 27.6, and 40.4% of patients in the low, intermediate, and high dose groups, respectively. Grade 3 or worse changes were observed in 8.3, 20.0, and 36.5% of patients in the low, intermediate, and high dose groups, respectively. Grade 6 changes were observed in 1.6, 4.6, and 19.2% of patients in the low, intermediate, and high dose groups, respectively. No statistically significant differences were observed among treatment groups when toxicity was evaluated as Grade 2 or worse. For toxicity of Grade 3 or worse, an chi-square test revealed P values of 0.04 (low vs. intermediate dose), 0.09 (intermediate vs. high dose), and 0.0005 (low vs. high dose). With the endpoint of possible necrosis (Grade 6), P values were 0.21 (low vs. intermediate dose), 0.05 (intermediate vs. high dose), and 0.003 (low vs. high dose). The median time to radiographic appearance of an effect (15 months) was not influenced by total dose or fraction size. CONCLUSIONS: A well described toxicity scale for white matter injury was applied successfully to patients with malignant glioma treated with definitive irradiation. Severe white matter changes continued to increase significantly as the total dose of hyperfractionated cranial irradiation was escalated. The time to onset of the white matter abnormalities appeared to be independent of dose. An ongoing Radiation Therapy Oncology Group study will allow correlation of white matter injury with prospective neuropsychometric testing.

Brain↗

PubMed1994

PSA confirmation of cure at 10 years of T1B, T2, N0, M0 prostate cancer patients treated in RTOG protocol 7706 with external beam irradiation.

PURPOSE: This study was done to correlate prostatic specific antigen values with clinical no evidence of disease status for 28 long-term survivors of external beam irradiation from Radiation Therapy Oncology Group Study #77-06, and confirm the clinical observation of cure. METHODS AND MATERIALS: One hundred and four patients in Radiation Therapy Oncology Group 77-06 with T1B T2 N0, M0 with pathologically known negative lymph node status, were previously shown to have a 10 year actuarial outcome equal to radical prostatectomy patients. Of these 104, 28 were 9-13 year survivors with clinically no evidence of disease by physical examination and imaging. RESULTS: Prostatic specific antigen was available or obtained in 17 patients, 15 of the 17 had prostatic specific antigen values of < 3.5 ngm/%, while 11 had values of < 1.5 ngm/%. Depending on which level one selects, 88% or 65% of clinical no evidence of disease 9-13 year survivors have a normal or low prostatic specific antigen. CONCLUSION: Prostatic specific antigen adds to the accuracy of determining clinical long-term cure and shows that 65-88% of patients who are clinical no evidence of disease are "biochemical" cures as well. These correlation percentages are quite similar to the largest contemporary surgical series, and strongly support the concept and fact of cure of prostate cancer with radiation.

Aged↗

PubMed1994

Patterns of Care and RTOG studies in prostate cancer: long-term survival, hazard rate observations, and possibilities of cure.

PURPOSE: This study was undertaken to show the long-term survival and probability of cure of prostate cancer patients treated with external beam radiation in USA national surveys and in the prospective clinical trials of the RTOG. METHODS AND MATERIALS: Two national patterns of care surveys of patients treated in 1973 and 1978 are reported along with two RTOG prospective trials (7506 and 7706). Hazard rates represent the risk of death and are compared to the rate expected for a normal population. RESULTS: For patients with Stage A cancers, the survival is not different from the expected survival for any of the reported surveys. The hazard rate for death does not significantly exceed the expected hazard rate out to 15 years. For patients with Stage B cancer, there is a decrease in survival below expected and hazard rates show a continuing excess mortality as long as 15 years after treatment. For patients with Stage C cancers, there is a more rapid decrease in survival that then becomes parallel to the expected survival. Hazard rates indicate there has been a return to expected mortality at 15 years. CONCLUSION: These data make a strong argument for the long-term cure of prostate cancer by external beam radiation, and support the continued use and study of radiation therapy as a curative modality in prostate cancer. No similar national data is available for any other method of management.

Follow-Up Studies↗

PubMed1994

Treatment related sequelae following external beam radiation for prostate cancer: a review with an update in patients with stages T1 and T2 tumor.

The primary goal of radical radiation therapy in men with localized prostate carcinoma is cure and a secondary but important goal is to achieve cure without treatment related sequelae, such as loss of continence, rectal injury, loss of potency and the need for castration. A literature review of 2,611 men undergoing irradiation for all stages of localized prostatic carcinoma documented a 0.2% incidence of treatment related mortality, 1.9% severe complications, 0.9% incontinence and 33 to 60% maintenance of full potency 5 or more years after treatment. A separate analysis was made of 331 patients with only early tumors (stages T1 and T2) treated with conventional external beam radiation therapy to doses of 63 to 74 Gy. from 2 individual centers (Massachusetts General Hospital and M.D. Anderson Hospital) and 1 multi-institutional group (Radiation Therapy Oncology Group). Median followup was 6.1 years; however, in 2 series followup ranged to 14 years. This analysis revealed frequencies of treatment associated sequelae of 0% for mortality, 0% severe complications, 0.4% urinary incontinence, 5.4% genitourinary structures (1.2% persisting), 5.1% hematuria (0.9% persisting) and 5.4% rectal bleeding (0.6% persisting). This composite analysis of men undergoing irradiation for stages T1 and T2 tumors with conventional fractionation and doses indicates that acute morbidity is minor and usually transient, severe injury is rare, most late gastrointestinal and genitourinary symptoms of radiation injury are neither permanent nor debilitating, and few symptoms of radiation injury develop beyond 5 years from treatment. These data, combined with the low progression rates (using prostate specific antigen criteria) following irradiation of men with early tumors, further substantiate the primary role of radical radiotherapy in the treatment of surgical risk adversive patients.

Erectile Dysfunction↗

PubMed1993

Influence of location and extent of surgical resection on survival of patients with glioblastoma multiforme: results of three consecutive Radiation Therapy Oncology Group (RTOG) clinical trials.

PURPOSE: The influence of tumor site, size, and extent of surgery on the survival of patients with glioblastoma multiforme treated on three consecutive prospectively randomized Radiation Therapy Oncology Group trials employing surgery and irradiation plus or minus chemotherapy was studied. METHODS AND MATERIALS: Six hundred forty-five patients with a diagnosis of glioblastoma multiforme on central pathological review were analyzed for survival with respect to known prognostic factors, that is, age and Karnofsky Performance Status, as well as extent of surgery, site, and size. Surgical treatment consisted of biopsy only in 17%, partial resection in 64%, and total resection in 19%. Tumors were located in frontal lobe in 43%, temporal lobe in 28%, and parietal lobe in 25%. Maximum tumor diameter as determined on computed tomography or magnetic resonance imaging scans was less than 5 cm for 38%, between 5-10 cm for 56% and greater than 10 cm for 6% of patients. The extent of surgical therapy was the same for tumors greater than 5 or greater than 10 cm, whereas total resection was more often performed for tumors less than 5 cm. The extent of surgery did not appear to vary with age or site. RESULTS: Patients undergoing total resection had a median survival of 11.3 months compared to 6.6 months for patients with a biopsy only. A significant difference in median survival was also found for partial resection versus biopsy only treatment (10.4 vs. 6.6 months). There was no difference in survival for the different tumor sizes. Patients with frontal lobe tumors survived longer than those with temporal or parietal lobe lesions (11.4 months, 9.1 months, and 9.6 months, respectively) (p = 0.01). A Cox multivariate model confirmed a significant correlation of age, Karnofsky Performance Status, extent of surgery, and primary site with survival. The best survival rates occurred in patients who had at least three of the following features: < 40 years of age, high Karnofsky Performance Status, frontal tumors, and total resection (17 months median). CONCLUSION: We conclude that biopsy only yields inferior survival to more extensive surgery for patients with glioblastoma multiforme treated with surgery and radiation therapy.

Adult↗

PubMed1993

Analysis of early and late deaths on RTOG non-small cell carcinoma of the lung trials: comparison with CALGB 8433.

UNLABELLED: In a major study that showed a treatment advantage for induction chemotherapy followed by radiation therapy (CALGB 8433), there was a significantly (P = 0.02) lower proportion of patients dying within 105 days of registration in the chemotherapy/radiation arm than the radiation therapy arm; without this difference, the overall survival was marginally better (P = 0.059) for the chemotherapy/radiation group. A retrospective analysis of RTOG trials sought explanations for the phenomenon. MATERIALS AND METHODS: Patients who fit the CALGB eligibility criteria and received radiation therapy alone in four prospective trials of the RTOG conducted between 1983 and 1989 were analyzed to determine factors that distinguished patients dying within 105 days from longer survivors. Two were trials of altered fractionation and two used standard fractionation. Of 683 patients identified, 107 (15.7%) died within 105 days after registration. The log linear model was used to evaluate relationships between death within 105 days and known prognostic factors. Karnofsky performance status (KPS), < 90 vs. > or = 90, was the only factor significantly related to death within 105 days (P = 0.0052). A Cox model with the same factors plus fractionation and total dose found KPS and T-stage associated with overall survival (P = 0.0005 and 0.025, respectively). The choice of the hyperfractionation arm (HFX) for Phase III study (69.6 Gy at 1.2 Gy b.i.d.) was based in part on comparison with standard fractionation (STD) from a concurrent RTOG protocol, 8321. Review of early deaths showed that this HFX arm had a lower proportion of patients dying within 105 days (7.9%) than STD in 8321 (21.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Evaluation of 45 degrees C hyperthermia and irradiation. II. A phase I clinical trial in humans by the Radiation Therapy Oncology Group.

This report describes the experience in 40 evaluable patients entered into a Radiation Therapy Oncology Group (RTOG) study to evaluate the feasibility of administering 45 degrees C for 15 minutes for superficial malignant lesions: 18 patients (45%) tolerated only 1 heat session at 45 degrees C; 7 (17.5%), 2 sessions; 4 (10%), 3 sessions; and 3 (7.5%) tolerated > or = 4 sessions. The overriding reason for discontinuing at 45 degrees C treatment was pain. Of the 40 evaluable patients, 22 (55%) had complete tumor regression, and 8 (20%) had partial regression. Tumors < or = 3 cm in diameter had significantly better complete tumor response than lesions > 3 cm (85% vs 41%) (p = .02). We conclude that 45 degrees C heating is difficult to use in patients chiefly because of pain; this may be due in part to inadequacy of currently available external hyperthermia equipment. Caution must be exercised in the application of thermal isoeffect heat dose concepts in clinical practice until further trials have been performed and a better understanding of the time-temperature relationship is established.

Adenocarcinoma↗

PubMed1992

Does extent of surgery influence outcome for astrocytoma with atypical or anaplastic foci (AAF)? A report from three Radiation Therapy Oncology Group (RTOG) trials.

103 patients with the diagnosis of AAF were identified from the RT/BCNU arms of 3 RTOG malignant glioma trials. Pre-treatment tumor size was less than 5 cm for 48% and greater than or equal to 5 cm for 52%, and tumor sites were frontal lobe in 55%, temporal in 25%, and parietal in 16%. Surgery consisted of biopsy for 30%, partial resection for 56%, and total resection for 14%. Extent of surgery correlated with age, with 81% of patients less than 40 undergoing partial/total resection vs. 60% of those over 40 (P = 0.019). The median survival time (MST) of patients undergoing partial/total resection was 49 mo., vs. 18 mo. for those biopsied only (P = 0.002). Patients with frontal location had longer MST than those with non-frontal lesions (MST: 49 vs. 25 mo., P = 0.047), while no survival difference was apparent by univariate analysis of tumor size. Multivariate analysis demonstrated that only younger age, frontal location, and smaller tumor size correlated significantly with extended survival. Extent of surgery was not predictive. The close correlation between young age and extensive surgery obscures the survival advantage for greater surgery seen with univariate analysis. Smaller tumor size and frontal location favorably influence outcome even when adjusted by age.

Adult↗

PubMed1992

Comparison of pathologic and clinical evaluation of lymph nodes in prostate cancer: implications of RTOG data for patient management and trial design and stratification.

RTOG 77-06 and 75-06 were studies of nodal irradiation in prostate cancer, for which the status of nodes was determined by lymph node dissection (LND), lymphangiography (LAG), or computer assisted tomography (CT) based on investigator preference. Actuarial 5 year endpoints of survival, NED survival, local recurrence and distant metastasis have been determined by stage for 805 eligible patients with a comparison of pathologic vs clinical (imaging test) determined nodal status. Patients with pathologically negative lymph nodes show significantly improved 5 year survival (Stage T-2 (B) 84% vs 77%, Stage T-3,4 (C) 82% vs 65%) and NED survival (Stage T-2 (B) 72% vs 63%, Stage T-3,4 (C) 64% vs 44%) compared to patients clinically negative. Free of metastasis rates are increased in Stage T-3,4 (C) pathologic negative patients compared to imaging negative patients (75% vs 60%). A comparison of clinical positive versus clinical negative patients shows no difference in survival, NED survival or rate of metastasis, while a similar comparison of pathologic positive versus pathologic negative shows significant difference for all three endpoints (survival: Stage T-2 (B) 84% vs 61%, Stage T-3,4 (C) 82% vs 66%, NED survival: Stage T-2 (B) 72% vs 32%, Stage T-3,4 (C) 64% vs 32%; free of metastasis: Stage T-2 (B) 82% vs 64%, Stage T-3,4 (C) 75% vs 44%). The clinical determination of nodal status, therefore, has no prognostic value in contrast to pathologic determination and should not be used for stratifying patients in clinical trials. The CT scans often used to evaluate nodal status are more useful if delayed until they can be done as part of the treatment planning process where the CT has value. When imaging tests suggest positive lymph nodes in prostate cancer patients, the imaging finding is confirmed by biopsy.

Humans↗

PubMed1992

The prognostic significance of race and survival from prostate cancer based on patients irradiated on Radiation Therapy Oncology Group protocols (1976-1985).

A number of studies have identified race as a prognostic factor for survival from prostate cancer. To evaluate the prognostic significance of race in a controlled setting, we evaluated 1294 patients treated on three prospective randomized trials conducted by the Radiation Therapy Oncology Group between 1976 to 1985. One-hundred and twenty (9%) of the patients were coded as black, while 1077 (83%) of the patients were coded as white. Protocol 7506 included 607 patients with clinical Stage T3-T4Nx or T1b-T2N1-2. Protocol 7706 included 484 patients with clinical Stage T1b or T2 who were node negative. Protocol 8307 included 203 Stage T2b-T4 patients with no lymph node involvement beyond the pelvis. Univariate and multivariate analyses were used to assess the possible independent significance of race and other prognostic factors, including Gleason score, serum acid phosphatase, nodal status, and hormonal status. Protocols 7706 and 8307 revealed that race was not of prognostic significance for disease-free or overall survival by either univariate or multivariate analysis. Univariate analysis of Protocol 7506 revealed that the median survival for blacks was somewhat shorter (5.4 years vs. 7.1 years, p = 0.02). This difference persisted after a multivariate analysis. A higher percentage of blacks treated on 7506 had an abnormally elevated serum acid phosphatase compared to whites (p = 0.006), and the time to distant failure tended to be shorter (p = 0.07). These findings suggest that blacks treated on 7506 may have had more extensive disease at presentation. Based on these prospective randomized trials, it is most likely that the lower survival noted for black Americans with prostate cancer reflects the tendency for blacks to present with more advanced disease. Differences in access to care, the quality of care received, and the impact of co-morbid conditions may explain the lower survival reported for black Americans elsewhere in the literature.

Black or African American↗

PubMed1991

Prognostic factors in unresectable hepatocellular cancer: Radiation Therapy Oncology Group Study 83-01.

The Radiation Therapy Oncology Group (RTOG) conducted a Phase I/II study in hepatocellular cancer that closed on September 9, 1987 and some results presented previously. Here, 17 patient characteristics are evaluated to identify any of prognostic significance. Two hundred sixteen patients were entered and 198 (74% with metastases and/or previous chemotherapy) were evaluable. Treatment began with an induction regimen of external beam radiotherapy to the liver (21.0 Gy, 3.0 Gy/Fx, 10 MV photons, 4 days per week) with low-dose chemotherapy (5-Fluorouracil (FU), 500 mg, i.v.; Doxorubicin, 15 mg, i.v.) on treatment Days 1, 3, 5 and 7. In the later stages of these studies, 56 patients received external beam radiotherapy as hyperfractionated treatment (1.2 Gy twice daily, 4 hours separation, 5 days per week, 24.0 Gy total) with similar chemotherapy. One month following induction therapy, cycles of radiolabeled antibody therapy were given every 2 months. Each cycle was derived from a different species of animal and consisted of 30 mCi I-131 antiferritin, Day 0, and 20 mCi, Day 5. On Day -1, 5-FU, 500 mg, and Adriamycin, 15 mg, were administered. The overall median survival for the entire group, including previously treated patients, was 4.9 months. The median survival for alpha-fetoprotein (AFP) - patients not previously treated was 10.5 months. Median survival for all AFP - patients was 8.5 months and for all AFP + patients was 4.6 months (p = 0.006). Of the 17 pretreatment characteristics investigated for prognostic value Karnofsky Performance Score (KPS) (80-100 vs. less than 80) (p = 0.0001), presence/absence of ascites (p = 0.0002), bilirubin level (less than 1.5 vs. greater than or equal to 1.5) (p = 0.018), SGOT (less than or equal to 35 vs. greater than 35) (p = 0.001); alkaline phosphatase (less than or equal to 95 vs. greater than 95) (p = 0.008) were found to be significant independently using a multivariant regression model. The relative risk of dying for the unfavorable component of each of these characteristics was 2.2, 2.0, 1.5, 1.9 and 1.7, respectively. Good and poor prognostic groups were then defined and compared to a similar patient population (RTOG study 83-19) with confirmation of the validity of the model. When stratification for these overpowering clinical factors was incorporated, AFP status was again significant with a relative death rate 1.80 times higher for AFP+ patients. Our recommendations for structuring future prospective randomized trials are discussed and include stratification by AFP status.

Antibodies↗

PubMed1991

The effect of overall treatment time on the outcome of definitive radiotherapy for localized prostate carcinoma: the Radiation Therapy Oncology Group 75-06 and 77-06 experience.

From 1976 to 1983, 1091 patients were entered into RTOG protocols 75-06 and 77-06. Of these, 780 patients complied with protocol requirements, received a minimum tumor dose of greater than or equal to 6500 cGy, and received no endocrine therapy. There were 78, 342, and 360 patients with localized prostate carcinoma, Stages T1b(A2), T2(B), and T3,4(C), respectively. The potential follow-up period ranges from 6 years 5 months to 13 years 3 months, with a median follow-up of 9 years. This study examines the influence of overall treatment time on the outcome of definitive radiotherapy for localized prostate carcinoma in this patient population. Within each stage, patients were divided into three groups according to the total number of elapsed days while on treatment: within 49 days (less than or equal to 7 weeks); 50 to 63 days (8 to 9 weeks); and greater than or equal to 64 days (greater than 9 weeks). Based on actuarial analysis, within each stage, the overall treatment time did not have any impact on the following: overall survival, NED survival, or local/regional control. When grouped under different histologic grades, that is, Gleason scores 2-5, 6-7, and 8-10, the actuarial local/regional control showed no statistical difference among the three groups. The actual local/regional failures were analyzed and stratified by stage and Gleason scores, and no statistical difference was noted among the three groups for each stratification. The range of local/regional failure rates among the three groups for T1b(A2), T2(B), and T3,4(C) disease were 0%-8%, 16%-23%, and 24%-27%, respectively. The corresponding range of local/regional failure rates for patients with Gleason scores of 2-5, 6-7, and 8-10 were 13%-14%, 18%-22%, and 22%-33%, respectively. The incidence of late complications was not related to the number of elapsed treatment days. Therefore, the overall treatment time does not have an impact on the outcome of definitive radiotherapy for localized prostate carcinoma. It is hypothesized that prostate carcinoma behaves as late-reacting tissue in which there is little, if any, accelerated repopulation of clonogenic tumor cells during the later half of a protracted course of radiotherapy. This observation is in direct contrast to that suggested for head and neck carcinoma and bears important implications in daily radiotherapeutic management of patients with prostate carcinoma.

Follow-Up Studies↗

PubMed1991

Long-term treatment sequelae following external beam irradiation for adenocarcinoma of the prostate: analysis of RTOG studies 7506 and 7706.

Significant late intestinal and urinary morbidity from external beam irradiation for adenocarcinoma of the prostate has been a constant concern of both the urologist and the radiation oncologist. We analyzed two large Radiation Therapy Oncology Group trials (7506 and 7706) using primary irradiation in the treatment of local or locoregional adenocarcinoma of the prostate to assess morbidity via the Radiation Therapy Oncology Group scoring scheme (grade 1-5). One thousand twenty patients were treated in total with a minimum follow-up of 7 years in the surviving patients. There was a 3.3% incidence of intestinal complications defined as grade 3 toxicity or more with .6% of patients experiencing bowel obstruction or perforation. Urinary complications defined as grade 3 toxicity or more were found in 7.7% of patients with only 0.5% experiencing morbidity that would require a major surgical intervention such as laparotomy, cystectomy, or prolonged hospitalization. Intestinal and urinary complications were evaluated in reference to several parameters that might have an impact on their incidence (i.e., previous laparotomy, stage of disease, hypertension, positive lymph nodes, previous transurethral resection, total dose, and energy of accelerator used). Only total dose (greater than 70 Gray) was found to have a significant impact on the incidence of the urinary complications. None of these factors had a significant impact on the incidence of intestinal complications. These data from two large multi-institutional trials represent a fair estimate of the actual incidence of major intestinal and urinary complications from external beam irradiation in the management of local and locoregional adenocarcinoma of the prostate. Since the incidence of these major complications remains very low, we believe that external beam irradiation remains an excellent alternative to radical prostatectomy in the management of these patients.

Adenocarcinoma↗

PubMed1991

Biopsies of non-small cell lung cancer: central review in cooperative studies of the Radiation Therapy Oncology Group.

Cooperative trials involving many institutions have long been recognized as a major means of gaining enough experience in a reasonably short period of time to determine the effectiveness of new approaches in cancer therapy. In order to make such multiinstitutional trials meaningful, it is necessary to have uniform and objective diagnostic standards in histopathology. Large cooperative therapeutic trials, such as the Radiation Therapy Oncology Group (RTOG) constructs, must rely on the histopathologic diagnoses of many pathologists from varied institutions or subject them to central review, which is a longer and costlier process. This study is an assay of the need for central review in cooperative studies on non-small cell lung cancer, which includes squamous cell, large cell, adenocarcinomas, and combined squamous cell and adenocarcinomas.

Adenoma↗

PubMed1990

Accelerated fractionation radiation therapy for liver metastases: selection of an optimal patient population for the evaluation of late hepatic injury in RTOG studies.

The palliation of hepatic metastases represents a major therapeutic problem in oncology. The generally unfavorable prognosis of patients with liver metastasis may complicate the evaluation of the efficacy and toxicity of various therapeutic modalities. The Radiation Therapy Oncology Group (RTOG) is evaluating new accelerated fractionation schemes for hepatic irradiation. In designing this study it became necessary to identify a favorable subpopulation of patients with an expected median survival of 6 months in whom the late effects of treatment could be evaluated. Data from two RTOG liver metastases studies (7605 and 8003) were analyzed using multi-variate techniques. Cases with a serum bilirubin level of greater than 1.5 mg%, performance score of less than 50, and gastric or pancreatic primary carcinomas were initially excluded because of the adverse influence of these factors on survival. One hundred and ninety cases met the criteria for inclusion in this analysis. A loglinear model was used to identify the patient characteristics associated with a favorable prognosis for survival. These included a performance score of 80-100, colorectal carcinoma primary, and no extrahepatic metastases. A logistic regression equation was derived and confirmed that the probability of surviving at least 6 months depended on the effects of performance score, primary site and the presence or absence of extra-hepatic metastases. Patients with all three favorable factors constituted 30% of the evaluable study population and had a predicted survival of 50% at 6 months. A patient population with these characteristics will be used to study the late effects of accelerated fractionated radiation therapy on the liver.

Breast Neoplasms↗

PubMed1989

Correlation of prostate-specific acid phosphatase and prostate-specific antigen immunocytochemistry with survival in prostate carcinoma.

Prostate-specific acid phosphatase, a secretory product of prostatic cells, may be a secondary product of the interaction of hormones with their receptor proteins. In this study we have examined two independent patient populations to see whether the intensity or extent of prostate-specific acid phosphatase and/or prostate-specific antigen staining correlated with survival and hormonal manipulation. One population of 24 patients was selected from patients undergoing surgical resection for adenocarcinoma Stage B or C at the Mayo Clinic. The second population of 123 patients was obtained from Radiation Therapy Oncology Group Protocols 75-06 and 77-06. Tissue from both populations was analyzed. In both populations, the intensity of prostate-specific acid phosphatase staining correlated with survival in a statistically significant manner. Staining with prostate-specific antigen was present in greater than 90% of specimens; data was therefore not analyzed. In those patients who subsequently relapsed and were subjected to hormonal manipulation, there appeared to be a higher likelihood of response to hormones with intense prostate-specific acid phosphatase staining.

Acid Phosphatase↗

PubMed1989

Impact of surgical staging in evaluating the radiotherapeutic outcome in RTOG phase III study for A2 and B prostate carcinoma.

Radiation Therapy Oncology Group (RTOG) protocol 7706 was a randomized Phase III study designed to test the value of elective (prophylactic) pelvic irradiation in addition to prostatic irradiation in patients with carcinoma of the prostate with no clinical evidence of tumor extension through the capsule. Eligible patients were those who had clinical Stage T1bNOMO (A2) or T2NOMO (B), who did not have curative surgery, and who had no evidence of lymph node metastases. Assessment of the regional lymphatics was mandatory but, at the discretion of the investigator, lymphangiography (LAG) or staging lymphadenectomy (SL) could be used. A total of 445 eligible and analyzable patients were entered in the study between 1978 and 1983 when the study was closed. The median follow-up was 7 years; minimum follow-up was 5 years. There were no significant differences in survival or local control whether treatment was administered to the prostate or to the prostate and pelvic lymph nodes. The nodal status for 117 (26%) patients was assessed by staging lymphadenectomy (SL) whereas for 328 (74%) patients it was assessed by lymphangiography (LAG). Pretreatment characteristics felt to have impact on survival were evaluated and found to be free of serious imbalance between the staging lymphadenectomy and lymphangiography groups. Compared to the lymphangiography group, the staging lymphadenectomy group showed better overall survival (87% to 76% at 5 years, p = .02), better disease-free survival (76% to 63% at 5 years, p = .008) and better metastases-free survival (88% to 82% at 5 years, p = .04). There was no difference between the groups in local control. The lymphangiography evaluation of pelvic nodes was clearly inferior for demonstration of the absence of pelvic node metastasis as reflected by reduced survival and increased metastasis.

Aged↗