PubMed Health⌕ Search

Biomedical subjects

T F Pajak

Publications and source records attributed to T F Pajak.

At least 55 records · Page 3Linked to original sources
PubMed1994

Chemotherapy as predictor of compliance.

Patient compliance with the increasingly complex adjuvant therapy protocols has always been of concern, particularly in the head and neck cancer population. The Head and Neck Intergroup recently concluded a phase III prospective randomized trial testing the addition of three courses of cisplatinum containing combination chemotherapy to standard treatment defined as surgery and postoperative radiotherapy for advanced stage III and IV squamous cell carcinoma. The chemotherapy was administered following the surgery prior to the postoperative radiotherapy. Variation from protocol is ranked retrospectively as minor acceptable, major acceptable, and major unacceptable. The incidence of major unacceptable variation from the protocol for radiotherapy immediately following the surgery was 15% vs. 19% in the population that completed all three courses of the chemotherapy (P < 0.10). However, for those patients that completed less than the three courses of chemotherapy, the incidence of major unacceptable variation in radiotherapy was 33% (P < 0.001). This observation was controlled for site, stage, performance status, age, sex, surgical margins and experience of participating institution. We conclude that compliance with a multicourse adjuvant chemotherapy regimen is predictive of subsequent compliance to radiotherapy in the head and neck cancer population.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Technically accurate intracavitary insertions improve pelvic control and survival among patients with locally advanced carcinoma of the uterine cervix.

The purpose of this study was to document whether the technical qualities of a brachytherapy application impacts on the outcome of patients with locally advanced cervix cancer treated by definitive irradiation. A previous report from the patterns of care study demonstrated the importance of brachytherapy in the treatment of locally advanced cervix cancer. Locally advanced disease was defined as FIGO stages Ib (if tumor diameter was < or = 4 cm), IIb (if disease was bilateral or involved the lateral aspect of either parametrium), and III. Localization films from 128 patients with locally advanced squamous cell carcinoma of the cervix were reviewed by a radiation physicist and a radiation oncologist with expertise in gynecologic radiotherapy. All patients received external beam irradiation followed by one brachytherapy application (median point A dose = 8040 cGy; range, 4083-10,020 cGy). Brachytherapy parameters assessed were (a) the distance between the right colpostat source and the distal tandem source, (b) the distance between the left colpostat source and the distal tandem source, and (c) the symmetry of colpostat placement. Implants were scored as "ideal" (n = 8) when all three parameters were deemed satisfactory, "unacceptable" (n = 17) when none of the parameters was deemed satisfactory, and "adequate" (n = 41) in all other cases. Significantly improved 5-year local control was seen when comparing ideal and adequate placements to unacceptable placements (68% vs 34%, P = 0.02). A strong trend toward improved 5-year survival was also noted among the group with ideal and adequate implants as opposed to unacceptable implants (60% vs 40%). Multivariate analysis showed that the technical adequacy of the brachytherapy implant was the most important prognostic discriminant of local control. In conclusion, these analyses demonstrate the direct influence of competent technical implant performance on tumor control and even survival. While only a small fraction of implants for cervical cancer are performed poorly in the United States, there is a need for continued emphasis of the principles for proper implant technique.

Adult↗
PubMed1994

Dose intensity of radiation therapy in non-small cell carcinoma of the lung: a review of RTOG data and strategies.

Prospective trials exploring questions of dose intensity for control of the local-regional tumor have been conducted by the Radiation Therapy Oncology Group for 20 years. Early studies established radiation therapy with a total dose of 60 Gy in 30 fractions as standard (STD) for unresectable non-small cell carcinomas of the lung (NSCCL). Hyperfractionated radiation therapy (HFX) with 1.2 Gy twice daily permitted higher total doses without increased normal tissue effects and led to comparison of STD vs. HFX (total dose 69.6 Gy in 58 fractions). Induction chemotherapy followed by STD, induction followed by concurrent chemotherapy and STD, and concurrent chemotherapy and HFX, have been explored in successive trials. Preliminary results of STD combined with chemotherapy suggest that increases in dose intensity increase local-regional control and survival. Confirmatory trials of increased dose intensity by combining chemotherapy with STD and HFX have been completed or are progressing.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Evaluation of preoperative radiation therapy in operable colorectal cancer.

MATERIALS AND METHODS: Patients with operable colorectal cancer in the ascending colon, descending colon, and rectum were randomized to 500 cGy before definitive surgery. Patients with stage A and B1 lesions received no further treatment. All patients with stage B2, B3, C1, C2, and C3 received a minimum of 4500 cGy postoperatively. RESULTS: Three hundred fifty-three patients were registered for the study. Three hundred one patients were available for analyses. Follow-up was a minimum of 5 years on all study patients. The majority of patients had rectal cancer. Complications of treatment were acceptable. Two hundred thirty-one patients had stage B2, B3, C1, C2, or C3 tumors. Estimated 5-year rates for no preoperative therapy versus preoperative therapy were as follows: local recurrence 29% versus 26%; metastasis 41% versus 43%; and survival 54% versus 54%. No statistical benefit was observed for preoperative treatment. CONCLUSIONS: In a prospective randomized trial designed to test the value of low-dose preoperative irradiation followed by surgery and postoperative irradiation, the authors were unable to observe any benefit to low-dose preoperative therapy in patients with unfavorable stages.

Adult↗
PubMed1993

Interruptions of high-dose radiation therapy decrease long-term survival of favorable patients with unresectable non-small cell carcinoma of the lung: analysis of 1244 cases from 3 Radiation Therapy Oncology Group (RTOG) trials.

PURPOSE: To determine if prolonged treatment time adversely affects survival for patients with inoperable non-small cell carcinoma of the lung. METHODS AND MATERIALS: Patients enrolled on three randomized studies (RTOG 8311, 8321, 8403) between 1983-1989 formed the database. Previous analyses found that the addition of thymosin (8321) or prophylactic cranial irradiation (8403) failed to prolong survival: both studies used thoracic irradiation with standard fractionation to 55-60 Gy in 30 fractions. In 8311, patients were treated by hyperfractionated radiation therapy to randomly assigned total doses of 60.0 Gy, 64.8 Gy, 69.6 Gy, 74.4 Gy or 79.2 Gy, 1.2 Gy twice daily, 5 days per week. Patients analyzed received +/- 4% of the assigned total dose and lived > 90 days (to ensure that all patients would have completed treatment). Completion < 5 days beyond protocol specifications was classified as "per protocol." Elapsed treatment time exceeding specifications by 5-9 days was a minor deviation, 10-13 days was a major deviation-acceptable, and > or = 14 days was a major deviation-unacceptable. Absolute survival was the endpoint to evaluate the effect of delays. The log rank statistic was used to test for survival differences in the univariate setting, the Cox regression model was used in the multivariate setting. RESULTS: Of 293 patients treated with standard fractionation, eight (2.7%) had deviations from the specified treatment time (six minor, two major-acceptable). With hyperfractionation, 90 (15%) patients had deviations (40 minor, 21 major-acceptable, 29 major-unacceptable). As the assigned dose increased, the deviation rate increased (9.7% for 60.0 Gy vs. 20.8% for 79.2 Gy). Survivals for hyperfractionation patients with any deviations in treatment time were significantly shorter than those treated "per protocol" (p = 0.16): estimated 2- and 5-years rates were 24% and 10% versus 13% and 3%, respectively. Multivariate analyses showed the delay effect to be entirely in patients treated with 69.6 Gy or higher; there was also dependence upon the patients' prognosis. In patients with favorable prognosis (KPS 90-100, weight loss < or = 5%, no N3), the difference in survival was pronounced (33% and 15% vs. 14% and 0% at 2- and 5-years, respectively). Such differences were not found in patients with unfavorable prognostic factors. CONCLUSIONS: Interruptions delaying completion of planned radiation therapy were more frequent with higher total doses (> or = 69.6 Gy). Favorable patients (high KPS, little weight loss, < N3 nodal metastasis) had markedly adverse effects on long-term survival associated with delays to completion of the planned total dose.

Adult↗
PubMed1993

The influence of field size and other treatment factors on pulmonary toxicity following hyperfractionated irradiation for inoperable non-small cell lung cancer (NSCLC)--analysis of a Radiation Therapy Oncology Group (RTOG) protocol.

PURPOSE: The risk of pulmonary toxicity, observed in an Radiation Therapy Oncology Group Phase I/II randomized dose escalation trial of hyperfractionated irradiation for nonsmall cell lung cancer, was analyzed with regard to custom vs. hand blocking and compliance to protocol specified treatment field parameters. MATERIALS AND METHODS: There were 832 evaluable cases analyzed. The protocol required field margins 2 cm beyond primary tumor and involved nodes. In 674, the field margins were considered "per protocol" or as having minor protocol variations. In 94, margins exceeded protocol specification ("excessive margin" group). In this group, the area (cm2) of the effective (blocked) field and the portion including lung was measured from simulator films with a computer scanning device. Based on size and location of the primary and nodal disease, "per protocol" fields were constructed and the area (cm2) of lung included beyond these margins was estimated. Patients from both groups who received less than 30 Gy to normal lung were excluded from analysis of pulmonary toxicity. RESULTS: Grade 1 acute lung toxicity was higher (p = .009) in the "excessive margin" group compared to the "per protocol" group, whereas late lung toxicity was not significantly different (p = .94). The risk of Grade 2 or greater acute toxicity increased as area of excess irradiated lung increased. Overall lung toxicity, defined as the greater of either acute or late toxicity, was evaluated by multivariate analysis, in relation to assigned dose, effective treated field area, and type of shielding. Overall maximum lung toxicity (> or = Grade 2) was significantly greater in the "excessive margin" group, when lung treated beyond protocol margins exceeded an area of 35 cm2, than in the "per protocol" group, but only when the effective treated field size was > or = 180 cm2 (68% vs. 37%; p = .02). This effect was independent of assigned total dose or type of shielding. CONCLUSION: For nonsmall cell lung cancer treated with hyperfractionated irradiation, the risk of overall pulmonary toxicity was increased for patients treated with field sizes in excess of protocol specified margins of tumor coverage in comparison to patients treated with protocol specified margins. This effect was seen only when the area of lung treated beyond protocol margins exceeded 35 cm2 and when the overall field size was below 180 cm2.

Carcinoma, Non-Small-Cell Lung↗
PubMed1993

A phase I/II study to evaluate accelerated fractionation via concomitant boost for squamous, adeno, and large cell carcinoma of the lung: report of Radiation Therapy Oncology Group 84-07.

PURPOSE: A Phase I/II trial was conducted by the Radiation Therapy Oncology Group from 1984 to 1989 for 355 evaluable patients with non-small-cell lung cancer to assess tolerance to and efficacy of accelerated fractionation irradiation via concomitant boost. METHODS AND MATERIALS: "Large" fields (primary tumor and locoregional lymph nodes) received 1.8 Gy followed after 4 to 6 hr by 1.8 Gy two to three times weekly to reduced "boost" fields (primary and involved nodes only). The total doses escalated during the study and started with 63 Gy in 5 weeks (45 Gy "large" field and 18 Gy "boost") for 61 patients. After follow-up for ongoing toxicity assessment, the total dose was increased to 70.2 Gy in 5.5 weeks (50.4 Gy "large" field and 19.8 Gy "boost") for the next 180 patients. The last 114 patients received 70.2 Gy in 5 weeks (45 Gy "large" field and 25.2 Gy "boost"). RESULTS: Pretreatment patient characteristics were well balanced between the three treatment arms. Grade 3 acute toxicity was 7% for the 63 Gy arm; it was 14% and 17% for the two 70 Gy arms. Grade 4 or greater acute toxicities (esophagitis and pneumonitis) were 2 to 3% for all three arms. Late toxicities ranged between 5 and 9% (> or = Grade 3) and 0 to 2% (> or = Grade 4), not statistically different among the three arms. There was no difference between the three regimens in median survival (9 months) or 1-year survival (39 to 44%). However, the 2-year survivals ranged from 16% (63 Gy) to 21% ("shortened" 70.2 Gy). Among 176 patients who had the same criteria as Cancer and Leukemia Group B protocol 84-33 (American Joint Committee on Cancer Staging, 1984, Stage III; Karnofsky performance status 70 to 100; < 6% weight loss), the 2-year survival rates ranged from 18 to 22%. CONCLUSION: Concomitant boost accelerated fractionation irradiation regimens for non-small cell lung cancer may offer improved long-term survival without enhanced late toxicity. While acute toxicity is somewhat increased, further refinement of the relationship of "large" to "boost" field doses may improve the therapeutic ratio. Further Phase I/II testing seems justified and necessary, before concomitant boost accelerated fractionation irradiation is tested in Phase III trials for NSCLC.

Adenocarcinoma↗
PubMed1993

The influence of treatment time on outcome for squamous cell cancer of the uterine cervix treated with radiation: a patterns-of-care study.

PURPOSE: To analyze the effect of total treatment time on infield pelvic control and survival for squamous cell carcinoma of the uterine cervix using the combined 1973 and 1978 Patterns of Care (PCS) data base. METHODS AND MATERIALS: Eight hundred thirty-seven evaluable patients were analyzed for the effect of total treatment time on outcome. The Kaplan-Meier method was used to estimate time-to-outcome annual rates. Comparisons of time to failure were performed with the log rank test. Multivariate analysis was performed using the Cox regression analysis. RESULTS: A highly significant decrease in survival (p = .0001) and pelvic control (p = .0001) was demonstrated as the total treatment time was increased from < 6, 6 to 7.9, 8 to 9.9, and 10+ weeks. Stage III accounted for the majority of the adverse effect from the prolongation of total treatment time. Multivariate analysis of total treatment time in addition to previously reported significant pretreatment and treatment factors from the PCS data base revealed three independent factors for infield recurrence, namely Stage I versus II versus III (p = .0001), total treatment time < 6 versus 6 to 7.9 versus 8 to 9.9 versus 10+ weeks (p = .003), and age > 50 versus < or = 50 years (p = .01). When the analysis was performed by stage to evaluate the effect of overall treatment time with respect to the extent of pelvic disease as defined by PCS, total treatment time continued to be an independent prognosticator for infield pelvic control (p = .01) and survival (p = .02) for Stage III but not Stages I and II. CONCLUSION: This study demonstrates a significant adverse effect on survival and pelvic control with prolongation of the total radiation treatment time for Stage III squamous cell cancer of the uterine cervix in multivariate analysis. In the future design of clinical trials, limitations on total treatment time should be rigorously controlled, and the effect of variations in this important factor by altered fractionation schemes should be studied.

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

"Compensated" split-course versus continuous radiation therapy of carcinoma of the tonsillar fossa. Final results of a prospective randomized clinical trial of the Radiation Therapy Oncology Group.

The Radiation Therapy Oncology Group conducted a prospective comparison of a compensated split course radiotherapy technique (300 cGy x 10, 3 weeks rest, 300 cGy x 10), versus continuous radiotherapy (200-220 cGy up to 6000-6600 cGy), in 137 evaluable patients. The complete response (CR) was 57% in 63 patients, treated with the split-technique vs 61% in 74 patients submitted to continuous course radiotherapy. The completion of therapy as planned was better in the split-technique, but acute and late tissue reactions were the same. Locoregional control of tumor at 5 years was 25% for split and 28% for continuous therapy. At 7 years this was 25% and 24%, respectively. Absolute survival in the split-course patients tended to be lower than in the continuous group, but when the sample of patients was enlarged by the addition of cases from similar trials of nasopharynx and base of tongue lesions, the survival difference was eliminated. On the basis of the results of this study we conclude that the stated compensated split-course technique gives equal clinical results as conventional continuous therapy, with the advantage of requiring fewer radiation fractions, and less burden on the patient and therapy facilities.

Aged↗
PubMed1992

Interruptions adversely affect local control and survival with hyperfractionated radiation therapy of carcinomas of the upper respiratory and digestive tracts. New evidence for accelerated proliferation from Radiation Therapy Oncology Group Protocol 8313.

Hyperfractionated radiation therapy (HFX) attempts to overcome tumor proliferation during treatment by permitting higher total doses in the same overall time as standard fractionation. Whereas interruptions, including splits, reduce local control with standard fractionation in carcinoma of the upper respiratory and digestive tracts, HFX might compensate for interruptions. Patients were randomized to receive total doses of 6720, 7200, 7680, and 8160 cGy, using 120 cGy twice daily, 5 days per week. Those analyzed received +/- 4% of assigned total dose and lived 90 days or more. Treatment was completed within 5 days of the time specified for each treatment arm in 233 patients; 48, 80, and 131 patients had delays 14, 10, and 5 days or more, respectively. Locoregional control and survival were significantly (P less than or equal to 0.03) reduced with delays of 5 days or more when corrected for prognostic factors. Late effects of radiation therapy were not affected by interruptions. These data support the hypothesis that proliferation (possibly accelerated) of tumor clonogens during treatment influences the outcome.

Aged↗
PubMed1991

Randomized dose-searching phase ILE/II trials of fractionation in radiation therapy for cancer.

This article describes a new design, phase ILE/II dose searching, used in four prospective, randomized, multicenter clinical trials of escalating total doses of hyperfractionated radiation. This design combines an experimental protocol with a statistical application of ranking and selection theory. Its purpose was to identify (within a certain margin of error) a dose that achieved the highest rate of clinical response from a set of doses that were tolerable in terms of both acute (within 90 days) and late (more than 90 days) toxic effects (LE). We calculated the number of patients required to reliably test toxicity under various assumptions. To determine the maximum tolerated total dose for hyperfractionated radiation, we randomly assigned patients with tumors that responded to radiation therapy in a dose-dependent manner from four body sites (lung, upper respiratory and digestive tract, bladder, and brain) to one of three regimens receiving total doses (D1, D2, or D3) differing by increments of 4.8 Gy. All patients received two fractions of 1.2 Gy each (separated by 4-6 hours) daily 5 days a week. The lowest total dose was set at the level considered tolerable with standard once-a-day radiation therapy. We tested tumor responses and late toxic effects of higher doses by assigning patients to these three regimens until acute effects and early estimates of late effects were found to be acceptable for the highest dose D3; thereafter, regimen D1 was closed, and additional patients were assigned to D2, D3, and D4 (an escalated total dose greater than D3 by an increment of 4.8 Gy). The assignment of patients was performed in a weighted manner (1:1:2), so that greater numbers were assigned to the highest dose regimen (whether D3 or D4) to allow rapid evaluation of the feasibility of the highest dose.

Clinical Trials as Topic↗
PubMed1991

5-year results of cisplatin and fluorouracil infusion in head and neck cancer.

As part of the developmental process for the Head and Neck Intergroup trial of adjuvant chemotherapy for advanced resectable head and neck carcinoma, in 1981 the Radiation Therapy Oncology Group, Philadelphia, Pa, conducted two nonrandomized pilot studies using chemotherapy consisting of three courses of cisplatin and fluorouracil infusion. Chemotherapy was administered prior to surgery in 42 patients (induction) and after surgery in an additional 29 patients (sequential). The populations were roughly comparable with respect to tumor site and stage. Twelve of the 42 patients in the induction group and seven of the 29 in the sequential group are alive and with no evidence of disease at the last reported follow-up. The median survival was 31 months in the sequential group vs 20 months in the induction group. Only two of the 26 patients with less than a complete clinical response following induction chemotherapy are still alive. Twenty-seven of the 42 patients who received induction chemotherapy did not undergo surgery as initially planned. Despite the lack of surgery, at 5 years the survival between the two groups was not significantly different (27% for the induction group vs 23% for the sequential group).

Adult↗
PubMed1991

Elapsed treatment days--a critical item for radiotherapy quality control review in head and neck trials: RTOG report.

For all randomized trials since 1978, the Radiation Therapy Oncology Group has required the study chairman for radiation therapy to review the treatment given to each patient. The chairman scores the compliance of the treatment borders, total dose, fraction, and total elapsed time relative to the protocol prescription at the primary site, regional nodes, and any critical structure. The individual parameters are then considered together to derive an "overall" treatment score. For two RTOG head and neck studies in patients with moderately and very advanced carcinomas, the "overall" treatment was classified as unacceptable if the treatment at primary was scored unacceptable with respect to dose, fractionation, and field borders. However, prolonged elapsed treatment was not included. Analysis of these studies with 426 evaluable patients was performed to assess the relationship of unacceptable "overall" treatment compliance with outcome. Patients with prolonged treatment elapsed days (14 days beyond the protocol prescription) exhibited significantly poorer loco-regional control (13% vs. 27% at 3 years with p = .007) and absolute survival (13% vs. 26% at 3 years with p = .01). As a result, the criteria for unacceptable "overall" treatment were revised to include prolonged elapsed treatment days. Further multivariate analyses showed the revised criteria identified patients with significantly poorer loco-regional control and absolute survival even after adjusting for other prognostic factors.

Carcinoma, Squamous Cell↗
PubMed1991

ASTRO plenary: interfraction interval is a major determinant of late effects, with hyperfractionated radiation therapy of carcinomas of upper respiratory and digestive tracts: results from Radiation Therapy Oncology Group protocol 8313.

A prospective, randomized, multi-institutional, Phase I(LE)/II trial of HFX was conducted by the RTOG between 1983 and 1987. Patients with histologically proven, inoperable squamous cell carcinoma of the upper respiratory and digestive tracts stratified by site, nodal status, and performance status, were assigned to one of three arms, were assigned to one of three arms, 67.2 Gy, 72.0 Gy, or 76.8 Gy. Fractions of 1.2 Gy were given twice daily, 5 days per week: intervals of 4 to 8 hours were permitted between fractions. After acceptable rates of acute normal tissue effects were found, the randomization was changed to evaluate a new higher total dose, 81.6 Gy. Of 479 patients entered, 447 were analyzed, 63 on 67.2 Gy, 129 on 72.0 Gy, 117 on 76.8 Gy, and 138 on 81.6 Gy. The treatment arms were well balanced with respect to pretreatment characteristics. Acute reactions consisted almost entirely of pseudomembranous inflammation. "Severe" (Grade 3) acute reactions were reported in 33% to 41% and grade 4 reactions were found in 0 to 3% of patients, with no differences in frequencies among the four arms. Toxicities that developed or persisted beyond 90 days after the first treatment (408 patients evaluable greater than 90 days) did not differ among arms: grade 3+ reactions occurred in 10% to 14%, and grade 4+ effects (necroses) were reported in 5% at 67.2 Gy, 3% at 72.0 Gy, 7% at 76.8 Gy, and 2% at 81.6 Gy. Grade 3+ acute reactions occurred in 40% of patients when the interfraction interval was less than or equal to 4.5 hours versus 31% with greater than 4.5 hours (p = .03). Interfraction intervals less than or equal to 4.5 hours were associated with higher frequencies of grade 4+ late effects in all four arms, 8% of 197 patients with less than or equal to 4.5 hours versus 1% of 211 patients with greater than 4.5 hours. Estimates of late toxicity at 1, 2, and 3 years were 5.5%, 9.8%, and 15.4% with intervals less than or equal to 4.5 hours, versus 1.7% at all three periods for greater than 4.5 hours (p = .006). Local-regional control at 2 years was 25% for the assigned dose of 67.2 Gy compared to 43% to 45% for the three higher doses (p = .01), but a similar comparison for survival showed no significant difference (p = .35). There was no evidence for an effect of interfraction interval on either local-regional control (p = .38) or survival (p = .28).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

The Radiation Therapy Oncology Group: an update of clinical research activities.

This paper provides an introduction into the clinical activities of the RTOG (Radiation Therapy Oncology Group), its goals, its organization, its format for protocol development, and presents major areas of achievement. It provides an organizational chart of the group, a disease site modality cross-reference for protocols, and appendices which provide the key published results of the Group's clinical activities. This paper presents an important overview of the RTOG clinical research activities, which are designed to improve the role of radiation therapy.

Clinical Protocols↗
PubMed1991

Five-year survival after hyperfractionated radiation therapy for non-small-cell carcinoma of the lung (NSCCL): results of RTOG protocol 81-08.

RTOG Protocol 81-08, a feasibility study of hyperfractionated radiation therapy (HFX) with 1.2 Gy twice daily separated by 4-6 hours for non-small-cell cancer of the lung (NSCCL), was completed in 1983. Encouraging short-term results in a recently closed trial of HFX for NSCCL (RTOG 83-11) led to assessment of long-term outcome in the earlier trial. Of 120 evaluable patients who were assigned to total doses from 50.4 Gy to 74.4 Gy, all 5 of the 5-year survivors came from the 79 patients assigned to receive 69.6 Gy. The 5-year survival rates for the 79 patients were 14.3 +/- 9.4% for clinical RTOG Stage II, 5.9 +/- 4.0% for Stage III, and 3.2 +/- 3.2% for Stage IV. Combined Stage II and III 5-year survival rates were 8.3 +/- 4.0% for HFX 69.6 Gy compared to 5.6 +/- 1.5% for standard once-a-day irradiation in concurrent RTOG trials.

Carcinoma, Non-Small-Cell Lung↗