Roger W. Byhardt

Recursive partitioning analysis (RPA) of prognostic factors in three radiation therapy oncology group (RTOG) brain metastases trials

PURPOSE Promising results from new approaches such as radiosurgery or stereotactic surgery of brain metastases have recently been reported. Are these results due to the therapy alone or can the results be attributed in part to patient selection? An analysis of tumor/patient characteristics and treatment variables in previous Radiation Therapy Oncology Group (RTOG) brain metastases studies was considered necessary to fully evaluate the benefit of these new interventions. METHODS AND MATERIALS The database included 1200 patients from three consecutive RTOG trials conducted between 1979 and 1993, which tested several different dose fractionation schemes and radiation sensitizers. Using recursive partitioning analysis (RPA), a statistical methodology which creates a regression tree according to prognostic significance, eighteen pretreatment characteristics and three treatment-related variables were analyzed. RESULTS According to the RPA tree the best survival (median: 7.1 months) was observed in patients < 65 years of age with a Karnofsky Performance Status (KPS) of at least 70, and a controlled primary tumor with the brain the only site of metastases. The worst survival (median: 2.3 months) was seen in patients with a KPS less than 70. All other patients had relatively minor differences in observed survival, with a median of 4.2 months. CONCLUSIONS Based on this analysis, we suggest the following three classes: Class 1: patients with KPS > or = 70, < 65 years of age with controlled primary and no extracranial metastases; Class 3: KPS < 70; Class 2- all others. Using these classes or stages, new treatment techniques can be tested on homogeneous patient groups.

Combined Chemotherapy and Radiotherapy Compared with Radiotherapy Alone in Patients with Cancer of the Esophagus

BACKGROUND The efficacy of conventional treatment with surgery and radiation for cancer of the esophagus is limited. The median survival is less than 10 months, and less than 10 percent of patients survive for 5 years. Recent studies have suggested that combined chemotherapy and radiation therapy may result in improved survival. METHODS This phase III prospective, randomized, and stratified trial was undertaken to evaluate the efficacy of four courses of combined fluorouracil (1000 mg per square meter of body-surface area daily for four days) and cisplatin (75 mg per square meter on the first day) plus 5000 cGy of radiation therapy, as compared with 6400 cGy of radiation therapy alone, in patients with squamous-cell carcinoma or adenocarcinoma of the thoracic esophagus. The trial was stopped after the accumulated results in 121 patients demonstrated a significant advantage for survival in the patients who received chemotherapy and radiation therapy. RESULTS The median survival was 8.9 months in the radiation-treated patients, as compared with 12.5 months in the patients treated with chemotherapy and radiation therapy. In the former group, the survival rates at 12 and 24 months were 33 percent and 10 percent, respectively, whereas they were 50 percent and 38 percent in the patients receiving combined therapy (P less than 0.001). Seven patients in the radiotherapy group and 25 in the combined-therapy group were alive at the time of the analysis. The patients who received combined treatment had fewer local (P less than 0.02) and fewer distant (P less than 0.01) recurrences. Severe and life-threatening side effects occurred in 44 percent and 20 percent, respectively, of the patients who received combined therapy, as compared with 25 percent and 3 percent of those treated with radiation alone. CONCLUSIONS Concurrent therapy with cisplatin and fluorouracil and radiation is superior to radiation therapy alone in patients with localized carcinoma of the esophagus, as measured by control of local tumors, distant metastases, and survival, but at the cost of increased side effects.

Common toxicity criteria: version 2.0. an improved reference for grading the acute effects of cancer treatment: impact on radiotherapy

In 1997, the National Cancer Institute (NCI) led an effort to revise and expand the Common Toxicity Criteria (CTC) with the goal of integrating systemic agent, radiation, and surgical criteria into a comprehensive and standardized system. Representatives from the Radiation Therapy Oncology Group (RTOG) participated in this process in an effort to improve acute radiation related criteria and to achieve better clarity and consistency among modalities. CTC v. 2.0 replaces the previous NCI CTC and the RTOG Acute Radiation Morbidity Scoring Criteria and includes more than 260 individual adverse events with more than 100 of these applicable to acute radiation effects. One of the advantages of the revised criteria for radiation oncology is the opportunity to grade acute radiation effects not adequately captured under the previous RTOG system. A pilot study conducted by the RTOG indicated the new criteria are indeed more comprehensive and were preferred by research associates. CTC v. 2.0 represents an improvement in the evaluation and grading of acute toxicity for all modalities.

Progress report of combined chemoradiotherapy versus radiotherapy alone in patients with esophageal cancer: an intergroup study.

PURPOSE The present intergroup phase III randomized study compared combined chemotherapy (CT) plus radiotherapy (RT) treatment versus RT only in patients with locally advanced esophageal cancer. MATERIALS AND METHODS Two courses of chemotherapy during 50 Gy RT followed by additional two courses of the same CT, versus 64 Gy RT alone were investigated. CT consisted of cisplatin 75 mg/m2 on day 1 [corrected] and fluorouracil (5FU) 1,000 mg/m2/d on days 1 to 4 every 4 weeks with RT and every 3 weeks post-RT. The main objective of the study was to compare overall survival between the two randomized treatment groups. Patients were stratified by tumor size, histology, and degree of weight loss. RESULTS Sixty-two assessable patients were randomized to receive RT alone, and 61 to the combined arm. Patients characteristics were as follows: squamous cell cancer, 90% versus 85%; weight loss greater than 10 lb, 61% versus 69%; and tumor size, > or = 5 cm, 82% versus 80% on the RT and CT-RT arms, respectively. Systemic side effects, which consisted of nausea, vomiting, and renal and myelosuppression, occurred more frequently on the combined arm, while local side effects were similar in both groups. With a minimum follow-up time of 5 years for all patients, the median survival duration was 14.1 months and the 5-year survival rate was 27% in the combined treatment group, while the median survival duration was 9.3 months with no patients alive at 5 years in the RT-alone group (P < .0001). Additional patients (69) were treated with the same combined therapy and were analyzed. The results of the last group confirmed all of the results obtained with combined CT-RT in the randomized trial, with a median survival duration of 17.2 months and 3-year survival rate of 30%. CONCLUSION We conclude that cisplatin and 5FU infusion given during and post-RT of 50 Gy is statistically superior to standard 64-Gy RT alone in patients with locally advanced esophageal cancer.

Phase III trial of androgen suppression using goserelin in unfavorable-prognosis carcinoma of the prostate treated with definitive radiotherapy: report of Radiation Therapy Oncology Group Protocol 85-31.

PURPOSE Although androgen suppression results in a tumor response/remission in the majority of patients with carcinoma of the prostate, its potential value as an adjuvant has not been substantiated. MATERIALS AND METHODS In 1987, the Radiation Therapy Oncology Group (RTOG) initiated a randomized phase III trial of adjuvant goserelin in definitively irradiated patients with carcinoma of the prostate. A total of 977 patients had been accessioned to the study. Of these, 945 remained analyzable: 477 on the adjuvant arm and 468 on the observation arm. RESULTS Actuarial projections show that at 5 years, 84% of patients on the adjuvant goserelin arm and 71% on the observation arm remain without evidence of local recurrence (P < .0001). The corresponding figures for freedom from distant metastases and disease-free survival are 83% versus 70% (P < .001) and 60% and 44% (P < .0001). If prostate-specific antigen (PSA) level greater than 1.5 ng is included as a failure (after > or = 1 year), the 5-year disease-free survival rate on the adjuvant goserelin arm is 53% versus 20% on the observation arm (P < .0001). The 5-year survival rate (for the entire population) is 75% on the adjuvant arm versus 71% on the observation arm (P = .52). However, in patients with centrally reviewed tumors with a Gleason score of 8 to 10, the difference in actuarial 5-year survival (66% on the adjuvant goserelin arm v 55% on the observation arm) reaches statistical significance (P = .03). CONCLUSION Application of androgen suppression as an adjuvant to definitive radiotherapy has been associated with a highly significant improvement in local control and freedom from disease progression. At this point, with a median follow-up time of 4.5 years, a significant improvement in survival has been observed only in patients with centrally reviewed tumors with a Gleason score of 8 to 10.

Neoadjuvant combined modality program with selective organ preservation for invasive bladder cancer: results of Radiation Therapy Oncology Group phase II trial 8802.

PURPOSE This phase II study was designed to evaluate effectiveness and toxicity of a combined chemoradiotherapy program with selective bladder preservation in the management of patients with invasive bladder cancer. PATIENTS AND METHODS Ninety-one eligible patients with invasive bladder cancer stages T2M0 to T4AM0 suitable for radical cystectomy received two courses of methotrexate, cisplatin, and vinblastine (MCV regimen) followed by radiotherapy with 39.6 Gy and concurrent cisplatin. After complete urologic evaluation, operable patients who achieved complete response were selected for bladder preservation and treated with consolidation cisplatin-radiotherapy. RESULTS Of 91 eligible patients, 85 underwent complete urologic evaluation and 68 (75%; 95% confidence interval [CI], 59% to 84%) had documented complete responses. Fourteen operable patients with residual tumor underwent immediate cystectomy. Of 70 patients treated with consolidation cisplatin-radiotherapy, 36 subsequently developed bladder recurrences, 23 of which were invasive. Patients with invasive recurrence (n = 16), extensive noninvasive recurrence (n = 6), or severe treatment complications (n = 1) underwent salvage cystectomy. Thus, a total of 37 of 91 patients (40%) required cystectomy. The 4-year cumulative risk of invasive local failure (which includes induction failures) was 43% (95% CI, 33% to 53%). The 4-year actuarial risk of distant metastasis was 22% (95% CI, 13% to 31%). The 4-year actuarial survival rate of the entire group was 62% (95% CI, 52% to 72%). The 4-year actuarial rate of survival with bladder intact was 44% (95% CI, 34% to 54%). CONCLUSION Initial results of this combined chemoradiotherapy program show that bladder preservation can be achieved in the majority of patients, and that overall survival is similar to that reported with aggressive surgical approaches. Long-term survival and quality-of-life assessments require longer follow-up study.

RESPONSE, TOXICITY, FAILURE PATTERNS, AND SURVIVAL IN FIVE RADIATION THERAPY ONCOLOGY GROUP (RTOG) TRIALS OF SEQUENTIAL AND/OR CONCURRENT CHEMOTHERAPY AND RADIOTHERAPY FOR LOCALLY ADVANCED NON-SMALL-CELL CARCINOMA OF THE LUNG

PURPOSE The purpose of this study was to assess response, toxicity, failure patterns, and survival differences in three chemotherapy (ChT)/radiation therapy (RT) sequencing strategies for locally advanced non-small cell lung cancer (NSCLC). METHODS AND MATERIALS Five completed Radiation Therapy Oncology Group (RTOG) trials for Stage II-IIIA/B inoperable NSCLC patients employed one of the three following strategy groupings: 1) sequential ChT followed by standard RT (60 Gy in 6 weeks); 2) combined sequential and concurrent ChT and standard RT (60 Gy in 6 weeks); or 3) concurrent ChT and hyperfractionated RT (69.6 Gy in 6 weeks). All five trials required KPS > or = 70; two trials (314 patients) required <5% weight loss and three trials (147 patients) had no minimum weight loss requirement. In all five trials the ChT used cisplatin with either vinblastine or oral etoposide. Combining data for the five trials yielded an evaluable group of 461 patients. The three methods of sequencing ChT and RT were evaluated for differences in response, acute and late toxicity, patterns of failure, and survival. Acute toxicity was defined as that occurring within 90 days from the start of RT. Late toxicity was defined as that occurring after 90 days from the start of RT. Acute or late toxicity > or = grade 3 was defined as severe. Site of first failure was recorded by date. In-field failure excluded distant metastasis as a failure and included only tissue in the RT treatment field. Overall progression-free survival (PFS) was defined as survival without evidence of intra- or extrathoracic tumor or death from any cause. RESULTS Group 1 had a lower overall response rate (63%) compared to either Group 2 (77%) or Group 3 (79%), p = 0.03 and 0.003, respectively. Overall grade 4/5 acute toxicities were nearly equal between groups. The severe nonhematologic acute toxicities were significantly different by strategy group (p < 0.0001). Group 1 and 2 were not statistically different. Group 3 had significantly more patients with severe acute nonhematologic toxicity (55%) than either Group 1 (27%) or 2 (34%) with p < 0.0001 and p = 0.0005, respectively. This was due to a severe acute esophagitis rate of 34% for Group 3 versus 1.3% for Group 1 and 6% for Group 2 (p < 0.0001 for both comparisons). Overall grade 4/5 late toxicities did not differ by group. Severe late nonhematologic toxicities were different by group (p = 0.0098). Group 1 patients had significantly fewer severe late nonhematologic toxicities (14%) compared to patients in Groups 2 (26%) or 3 (28%) (p = 0.046 and 0.038, respectively). Severe late lung toxicity was 10% for Group 1 compared to 21% and 20% for Groups 2 and 3, respectively. Severe late lung toxicities differed by group (p = 0.033), but not severe late esophagitis (p = 0.077). There were no differences between the three strategy groups for patterns of first failure. The in-field failures were higher in Group 2 (71%) compared to Groups 1 (56%) and 3 (55%), p = 0.0478. Pairwise comparisons yielded p-values of 0.068 and 0.015 for Group 2 versus 1 and Group 2 versus 3, respectively. Three-year PFS was better in Group 2 (15%) and 3 (15%) compared to Group 1 (7%), but not statistically significant (p = 0.454). Similarly, in-field PFS was better in Group 2 (17%) and 3 (20%) than Group 1 (9%), but not significant (p = 0.167). There were improvements in 3-year survival for Group 2 (17%) and Group 3 (25%) compared to Group 1 (15%), but the differences were not statistically significant (p = 0.47). The same results were present for patients with less than 5% weight loss and patients with stage IIIA tumors. CONCLUSION Thus, concurrent ChT and hyperfractionated RT had a higher incidence of severe acute esophageal toxicity. Severe late lung toxicity with concurrent ChT/hyperfractionated RT, as well as with induction ChT followed by concurrent ChT/standard RT, may be greater compared to sequential ChT/RT. (ABSTRACT TRUNCATED)

Recursive partitioning analysis of 1999 radiation therapy oncology group (RTOG) patients with locally-advanced non–small-cell lung cancer (LA-NSCLC): Identification of five groups with different survival

PURPOSE Survival of patients with locally-advanced non-small-cell lung cancer (LA-NSCLC) is predicted by the stage of the disease and other characteristics. This analysis was undertaken to identify these characteristics in a large cooperative group patient population, as well as to define subgroups of the population with differing outcomes. PATIENTS AND METHODS Analysis included 1,999 patients treated in 9 RTOG trials between 1983 and 1994 with thoracic irradiation (RT) with (n = 355) or without chemotherapy (CT). RESULTS In univariate analysis, the following characteristics were significantly associated with an improved survival: use of CT, CT delivered without major deviation, abnormal pulmonary function tests, normal hemoglobin, protein, LDH and BUN, presence of dyspnea, hemoptysis, cough or hoarseness, uninvolved lymph nodes, T1 or T2 stage, no malignant pleural effusion (PE), weight loss of < 8%, Karnofsky performance status (KPS) of at least 90, adenocarcinoma histology, female gender, and age less than 70 years. Recursive partitioning analysis (RPA) was subsequently applied to identify 5 patient subgroups with significantly different median survival times (MST): Group I, KPS of > or = 90, who received chemotherapy (MST 16.2 months); Group II, KPS of > or = 90, who received no CT, but had no PE (MST 11.9 months); Group III, KPS < 90, younger than 70 years, with non-large cell histology (MST 9.6 months); Group IV, KPS > or = 90, but with PE, or KPS < 90, younger than 70 years, and with large cell histology, or older than 70 years, but without PE (MST 5.6-6.4 months); Group V, older than 70, with PE (MST 2.9 months). CONCLUSION Cisplatinum-based CT improves survival, for excellent prognosis of LA-NSCLC patients, over RT alone. The presence of a malignant pleural effusion is a major negative prognostic factor for survival. The identification of RPA prognostic groups among patients with LA-NSCLC provides prognostic information and may serve as a basis of stratification in future trials.

Comorbidity and Karnofksy performance score are independent prognostic factors in stage III non-small-cell lung cancer: an institutional analysis of patients treated on four RTOG studies

PURPOSE To determine the prognostic role of comorbidity in Stage III non-small cell lung cancer (NSCLC) treated definitively with radiotherapy alone. METHODS AND MATERIALS A total of 112 patients with clinical Stage III NSCLC (American Joint Commission on Cancer 1997) enrolled in four Radiation Therapy Oncology Group studies (83-11, 84-03, 84-07, and 88-08 nonchemotherapy arms) at a single institution were analyzed retrospectively for overall survival (OS) and comorbidity. Of the 112 patients, 105 (94%) completed their assigned radiotherapy. The median assigned dose was 50.4 Gy to the lymphatics (range 45-50.4 Gy) and 70.2 Gy to the primary tumor (range 60-79.2 Gy). Comorbidity was rated retrospectively using the Cumulative Illness Rating Scale for Geriatrics (CIRS-G) and Charlson scales. Karnofsky performance scores (KPSs) and weight loss were prospectively recorded. Because only 8 patients had a KPS of <70, these patients were combined with patients who had a KPS of 70. The OS of this group was compared with that of the patients with better KPSs (>70). RESULTS The median survival was 10.39 months (range 7.87-12.91). The 2-, 3-, and 5-year OS rate was 20.5%, 12.5%, and 7.1%, respectively. On univariate analysis, clinical stage (IIIA vs. IIIB) was found to be a statistically significant factor influencing OS (p = 0.026), and the histologic features, grade, tumor size as measured on CT scans, age, tobacco use, weight loss >or=5%, and total dose delivered to the primary tumor were not. A KPS of <or=70 (p = 0.001), the presence of a CIRS-G score of 4 (extremely severe; p = 0.0002), and a severity index of >2 (p <0.0001) were associated with statistically significant inferior OS. Multivariate analysis with clinical stage, KPS, and comorbidity (severity index) of all patients showed that a KPS <or=70 and severity index >2 were independently associated with inferior OS; clinical tumor stage was not found to be an independent prognostic factor. CONCLUSION KPS and comorbidity are important independent prognostic factors in Stage III NSCLC. Comorbidity should be included in protocols studying advanced stage NSCLC and used for stratification.

Anal sphincter conservation for patients with adenocarcinoma of the distal rectum: long-term results of radiation therapy oncology group protocol 89-02

PURPOSE To assess the outcome of a multi-institutional, national cooperative group study attempting functional preservation of the anorectum for patients with limited, distal rectal cancer. METHODS AND MATERIALS Between September 21, 1989 and November 1, 1992, a Phase II trial of sphincter-sparing therapy was conducted for patients with clinically mobile rectal cancers located below the pelvic peritoneal reflection. Protocol treatment was designed for patients who were, in the judgement of their attending surgeon, unsuitable for anal sphincter conservation in the context of anterior resection, and would have required abdominoperineal resection (APR) as conventional surgical therapy. Primary cancers were estimated to be 4 cm or less in largest clinical diameter, and occupied 40% or less of the rectal circumference. Chest radiography and computerized axial tomography (CT) of the abdomen and pelvis excluded patients with overt lymphatic or hematogenous metastases. Protocol surgery was intended to remove the primary cancer by en-bloc, transmural excision of an ellipse of rectal wall by transanal, transcoccygeal, or trans-sacral technique, while conserving the anal sphincter. Based on tumor size, T classification, grade, and adequacy of surgical margins, patients were allocated to one of three treatment assignments: observation, or adjuvant treatment with 5-fluorouracil (5-FU) and one of two different dose levels of local-regional radiation. After completion of protocol therapy, patients were observed with follow-up that included periodic general physical and rectal examination, determinations of CEA, abdominopelvic CT, chest radiography, and surveillance endoscopy. Sixty-five eligible and analyzable patients were registered. RESULTS With minimum follow-up of 5 years and median follow-up of 6.1 years, 11 patients have failed: 3 patients recurred local-regionally only, 3 patients had distant failure alone, and 5 patients manifested local-regional and distant failure. Eight patients died of intercurrent illness. Local-regional failure correlated with T-category revealed: T1 1/27 (4%), T2 4/25 (16%), and T3 3/13 (23%). Local-regional failure escalated with percentage involvement of the rectal circumference: 2/31 (6%) among patients with cancers involving 20% or less of the rectal circumference, and 6/34 (18%) among patients with cancers involving 21-40% of the circumference. Distant dissemination rose with T-category with 1/27 (4%) T1, 3/25 (12%) T2, and 4/13 (31%) T3 patients manifesting hematogenous spread. Eight patients (12%) required temporary or permanent colostomy. Five of 8 patients with local-regional recurrence achieved local-regional control with management including surgery, although 4 of these patients subsequently developed distant dissemination. Three patients (5%) had persistent, uncontrolled, local disease. Actuarial freedom from pelvic relapse at 5 years is 88% based on the entire study population, and 86% for the less favorable patients treated with adjuvant radiation and 5-FU. CONCLUSION Conservative, sphincter-sparing therapy is a feasible alternative treatment for selected patients with limited cancer involving the middle and lower rectum. Risk of both local and distant failure appears to escalate with increasing T-category (depth of invasion). Results achieved in the multi-institutional, cooperative group setting approximate results reported from single institutions.