Jean B. Owen

Factors Predicting the Use of Breast-Conserving Therapy in Stage I and II Breast Carcinoma

PURPOSE To define patterns of care for the local therapy of stage I and II breast cancer and to identify factors used to select patients for breast-conserving therapy (BCT). PATIENTS AND METHODS A convenience sample of 16,643 patients with stage I and II breast cancer treated in 1994 was obtained from hospital-based tumor registries. Histologic variables were determined from original pathology reports. RESULTS BCT was performed in 42.6% of patients. Multivariate analysis demonstrated that living in the Northeast United States (odds ratio [OR], 2.48; 95% confidence interval [CI], 2.16 to 2.84), having a clinical T1 tumor (OR, 2.51; 95% CI, 2.27 to 2.78), and having a tumor without an extensive intraductal component (OR, 2.07; 95% CI, 1.81 to 2.37) were the strongest predictors of breast-conserving surgery. Radiation therapy was given to 86% of patients who had breast-conserving surgery. Age less than 70 years was the most significant predictor of receiving radiation (OR, 2.11; 95% CI, 1.77 to 2.25). Tumor variables did not correlate with the use of radiation, but favorable tumor characteristics were associated with the use of breast-conserving surgery. CONCLUSION Despite strong evidence supporting the use of BCT, the majority of women continue to be treated with mastectomy. Predictors of the use of BCT do not correspond to those suggested in guidelines.

Outcome of Patients Receiving Radiation for Cancer of the Esophagus: Results of the 1992-1994 Patterns of Care Study

PURPOSE A Patterns of Care Study examined the records of patients with esophageal cancer (EC) treated with radiation in 1992 through 1994 to determine the national practice processes of care and outcomes and to compare the results with those of clinical trials. PATIENTS AND METHODS A national survey of 63 institutions was conducted using two-stage cluster sampling, and specific information was collected on 400 patients with squamous cell (62%) or adenocarcinoma (37%) of the thoracic esophagus who received radiation therapy (RT) as part of primary or adjuvant treatment. Patients were staged according to a modified 1983 American Joint Committee on Cancer staging system. Fifteen percent of patients had clinical stage (CS) I disease, 40% had CS II disease, and 30% had CS III disease. Twenty-six percent of patients underwent esophagectomy. Seventy-five percent of patients received chemotherapy; 84% of these received concurrent chemotherapy and radiation (CRT). RESULTS Significant variables for overall survival in multivariate analysis include the use of esophagectomy (risk ratio [RR] = 0.62), the use of chemotherapy (RR = 0.63), Karnofsky performance status (KPS) greater than 80 (RR = 0.61), CS I or II disease (RR = 0.66), and facility type (RR = 0.72). Age, sex, and histology were not significant. Preoperative CRT resulted in a nonsignificantly higher 2-year survival rate compared with definitive CRT alone (63% v 39%; P =.11), whereas 2-year survival by planned treatment rather than treatment given was 47.7% for preoperative CRT and 35.4% for definitive CRT (P =.23). Definitive CRT compared with definitive RT alone resulted in significantly higher 2-year survival (39% v 20.6%; P =.027) and lower 2-year local regional failure (30% v 57.9%; P =. 0031). CONCLUSION This study confirms the value of CRT in EC treatment. It indicates that the results obtained in practice settings nationwide are similar to those obtained in clinical trials and that KPS and the 1983 clinical staging system are useful prognostic indicators. The suggested value of esophagectomy and superiority of preoperative CRT over CRT alone in this study should be tested in a randomized trial.

Local control of carcinoma of the tonsil by radiation therapy: An analysis of patterns of fractionation in nine institutions

PURPOSE To investigate the importance to outcome of treatment for squamous cell carcinomas of the tonsillar fossa, of dose per fraction, overall treatment duration, and total dose. METHODS AND MATERIALS A collaborative retrospective study was undertaken in nine centers that used widely different dose-fractionation patterns for external beam radiation therapy. RESULTS There were 676 eligible cases treated only with photon beams during the years 1976-1985. The probability of local control (of the tonsillar fossa primary) was influenced by both T-stage and N-stage. Significant treatment parameters were total dose and overall treatment duration, but not dose per fraction. Over the range of about 40 to 90% and for a constant overall treatment duration, local tumor control probability increased by nearly 2% for each 1 Gy increase in total dose. For a constant total dose there was a decrease in the probability of local control associated with prolongation of overall treatment duration, presumed to result from accelerated regrowth of surviving tumor clonogens during the course of treatment. If it is assumed that accelerated regrowth occurred at a constant rate and began within 9 days of the start of treatment, an average of 0.53 Gy extra dose per days extension of treatment would be required to maintain a constant probability of local control. Correspondingly, the probability of local control from a constant dose would be lowered by an average of at least 1% for each days extension of treatment duration. However, the data are slightly more consistent with an average delay of as long as 30 days before onset of accelerated repopulation, with a consequent increase to an average of 0.73 Gy per day for the value of the compensatory dose. The alpha/beta ratio for this tumor is high enough that the effect of fraction size on the probability of local control can be ignored; a precise estimate is not possible because the best value for beta was close to zero. After accounting for the significant variables studied (treatment time, T-stage, N-stage), the dose-response curves for tumor control were still shallow, suggesting that there are additional causes for heterogeneity of responses among these tumors. CONCLUSIONS Total dose is important to treatment outcome: After accounting for other treatment variables, there is about a 2% per Gy increase in probability of tumor control over the ranges of control commonly achieved. Overall treatment duration is important. There is at least a 1% per day decrease in tumor control probability if delivery of a constant total dose is prolonged, requiring a compensatory increase in dose by 0.5-0.7 Gy per day to achieve a constant rate of tumor control. Fraction size is not, of itself, an important factor in the response of primary carcinoma of the tonsil. If a tumor has demonstrated a capacity for metastatic spread to lymph nodes, a higher total dose should be considered to achieve control rates at the primary site equivalent to those in node negative patients. Even after accounting for variables such as tumor stage, total dose, and overall treatment duration, there is sufficient heterogeneity in other undocumented determinants of tumor control to cause the tumor control probability curve to be a shallow function of dose.

Late normal tissue sequelae from radiation therapy for carcinoma of the tonsil: Patterns of fractionation study of radiobiology

PURPOSE To evaluate the influence of dose fractionation and other factors on the development of late complications in mandibular bone, muscle, and mucosa of the oral cavity after external beam radiation therapy for carcinoma of the tonsil. METHODS AND MATERIALS A retrospective analysis was made of the results in 676 patients treated with a spectrum of fractionation regimens in nine centers during the years 1976-1985. Only severe (Grades 3-4) late complications were analyzed. RESULTS With more than 5 years follow-up, it was found that total dose was a factor for all three types of complications, but that in other respects, the radiobiology of late-(> 3 months) developing mucosal ulcerations was different from that for mandibular necrosis and muscle injury. Dose per fraction was a significant factor for bone and muscle (estimated alpha/beta values of 0.85 Gy and 3.1 Gy, respectively). By contrast, mucosa showed no influence on response from change in fraction size over the range of approximately 1.0-3.5 Gy. Complications in bone and muscle were not related to overall treatment duration, whereas there was a significant inverse relationship for mucosa breakdown. The rate of development of complications was fastest in mucosa and slowest in bone. The appearance of complications by 4 years after treatment was about 80% of those developing by 8 years in the mucosa, 66% in muscle, and about 50% in bone. The high alpha/beta ratio, inverse relationship with overall treatment duration, and faster development of mucosal complications suggests that they may develop as a consequence of earlier mucosal injury. As anticipated, adequate retrospective analysis of acute complications could not be made even when objective criteria such as weight loss, unplanned delays in completing treatment, or hospitalization during treatment were the measures. Field size was a significant factor for mandible complications, but not for muscle or mucosa. CONCLUSION The radiobiological characteristics of bone and muscle were those characteristic of other late-responding tissues, whereas late sequelae in mucosa had radiobiological parameters similar to those for acute responses. Field size was a significant factor for bone complications but not for others.

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.

Seminoma of the testis: long term beneficial and deleterious results of radiation☆

PURPOSE The followup of 387 patients in a USA national survey of seminoma treated with radiation in 1973 and 1974 has been extended beyond 15 years to assess the long-term benefits and problems resulting from treatment. RESULTS Survival at 15 years is 83% for Stage I, 68% for Stage II; freedom from recurrence at 15 years is 93% for Stage I, 96% for Stage II; NED survival at 15 years is 80% for Stage I, 68% for Stage II; cause specific freedom from cancer death is 98% for Stage I and 97% for Stage II at 15 years. Second malignancy rates were 8% at 15 years, and observed in 14 patients versus 4.2 expected (p < .001). Deaths due to these second cancers were also increased with seven observed versus two expected (p < .01). Non-cancer intercurrent disease death occurred in 23 patients versus 7.5 expected (p < .01). The most frequent cause was cardiac death which appeared in 10 patients versus 4.4 expected (p < .05) and 8 of the 10 patients received mediastinal radiation. Two additional patients died of pulmonary fibrosis after mediastinal radiation. Mediastinal radiation correlated with all intercurrent disease and cardio-pulmonary deaths (p < .05), but not with second malignancies. With the exception of one, all patients experiencing cardiac death after mediastinal irradiation were 40 years or older at the time of treatment, with a range of 32-58 years and a mean interval to death of 9.8 years. CONCLUSIONS Recommendations for the future management of seminoma include: reducing the irradiated volume in the treatment of Stage I patients, completely eliminating mediastinal radiation in the treatment of patients with Stage IIA seminoma and treating patients with Stage IIB seminoma with chemotherapy. Radiation dose should not exceed 30 Gy for Stage I or 35 Gy for Stage IIA.

Compliance with breast-conservation standards for patients with early-stage breast carcinoma†

Multiple treatment guidelines and practice standards have been developed regarding the management of patients with breast carcinoma. Few evaluations of the penetration and utility of these practice standards have been performed. In 1992, the American College of Surgeons (ACOS), the American College of Radiology, the College of American Pathologists, and the Society of Surgical Oncology collaborated in establishing standards for breast‐conservation treatment (BCT). The authors sought to determine whether practice patterns for patients with breast carcinoma who underwent BCT were consistent with these standards 2 years after their dissemination and to establish whether compliance varied by the same patient and hospital variables that predicted for the amount of BCT performed.

The national practice for patients receiving radiation therapy for carcinoma of the esophagus: Results of the 1996–1999 Patterns of Care Study

PURPOSE A Patterns of Care Study (PCS) was conducted to evaluate the standards of practice for patients receiving radiation therapy for esophageal cancer from 1996 to 1999. This study examined the evaluation and treatment schemes used during this time and compared these results to the PCS data obtained between 1992 and 1994 to identify any fundamental changes in national practice. METHODS A national survey was conducted using a two-stage cluster sampling technique. Specific information was collected on 414 patients with esophageal cancer who received radiotherapy (RT) as part of definitive or adjuvant management at 59 institutions. Patients were staged according to the 1983 AJCC. Eligibility criteria for case review included RT between 1996 and 1999, no evidence of distant metastasis (including CT evidence of either supraclavicular or celiac nodes >1 cm), squamous cell or adenocarcinoma histology, Karnofsky performance status >60, tumors in the thoracic esophagus with <2 cm extension into the stomach, and no prior malignancies within the last 5 years. Statistical analysis was performed on the database using SUDAAN software to accurately reflect the type of sampling technique used by PCS. For the purpose of this analysis, institutions were stratified as either large or small based on the number of new cases seen each year. For the purposes of comparison, the 1992-1994 PCS esophageal survey results were subjected to the same statistical procedures and tests. RESULTS The median age of patients was 64 years. Seventy-seven percent were male, and 23% were female. Karnofsky performance status was >or=80% in 85% of patients. The racial profile mirrors the previous survey with 75% Caucasian, 21% African-American, 3% Asian, and <1% Hispanic. A review of the histology revealed a nearly 50:50 split between squamous cell and adenocarcinoma. Sixteen percent were clinical Stage I, 39% clinical Stage II, and 33% clinical Stage III according to the 1983 AJCC system. Workup included endoscopy (96%), CT of the chest (87%), CT of the abdomen (75%), and esophagram (64%). Endoscopic ultrasound (EUS) was used in 18% of cases as compared to <2% in the original survey (p < 0.0001). Patients treated at large centers were more likely to undergo EUS than those treated at small centers (23% vs. 12%, p = 0.047). Fifty-six percent of patients received concurrent chemoradiation as definitive treatment. There was a significant increase in the use of concurrent chemoradiation before planned surgical resection as compared to the original survey (27% vs. 10%, p = 0.007). Other schemes included RT alone (10%), postoperative RT (1%), and postoperative chemoradiation (5%). Forty-six percent of patients with adenocarcinoma underwent trimodality therapy as compared to 19% with squamous cell carcinomas (p = 0.0002). Patients undergoing preoperative chemoradiation were more likely to have had an EUS. The median total dose of external RT was 50.4 Gy, and the median dose per fraction was 1.8 Gy. Brachytherapy was used in 6% of cases. The chemotherapy agents most commonly used included 5-fluorouracil (82%), cisplatin (67%), and paclitaxel (22%). Paclitaxel was more commonly employed as part of a preoperative chemoradiation regimen than in the setting of definitive chemoradiation (46% vs. 12%, p = 0.03). Compared to the original survey, paclitaxel use significantly increased between 1996 and 1999 (0.2% vs. 22%, p = 0.001). CONCLUSIONS The Patterns of Care Survey confirms the use of concurrent chemoradiation as part of the national standards of practice for the management of esophageal cancer patients. A comparison with the previous study documents the significant rise in the use of EUS, preoperative chemoradiation followed by surgery, and the increasing use of paclitaxel as part of a combined modality regimen.

Carcinoma of the cervix: Patterns of care studies: Review of 1978, 1983, and 1988–1989 surveys

PURPOSE A review of the Patterns of Care Studies Process Survey data on carcinoma of the cervix conducted on patients in 1978, 1983, and 1988-89 was carried out to identify changes or trends in the demographics, evaluation, and treatment that might have occurred over this time period. METHODS AND MATERIALS Patterns of Care Studies conducted surveys on patients treated by radiation therapy for cervical carcinoma in 1978, 1983, and 1988-89. These surveys have compiled demographic and treatment data on a total of 993 patients. There is outcome data for the 1978 and 1983 surveys, but not for the 1988-89 survey because follow-up has not been collected yet. The demographic and treatment delivery data on all three surveys has been reviewed and analyzed and is the subject of this study. RESULTS There was no difference in the age distribution at the time of diagnosis of the patients in these surveys. The percentage of black patients remained constant in the three surveys, 19%, 17%, and 21%, respectively. The percentage of white patients was 76%, 78%, and 67%, but that of nonwhite/nonblack patients was 3%, 4%, and 12% (p < 0.001). The distribution of patients by stage was similar in the first two surveys. In the third survey, there was a decrease in the percentage of patients with Stage IA and IB (first = 35%; second = 38%; third = 29%) with a concurrent increase in Stage IIIA and IIIB patients (first = 20%; second = 18%; third = 26%). The surveys showed a major change in the pretreatment evaluation tests used. There was a progressive decrease in the use of intravenous pyelogram (IVP) (86 to 42%), barium enema (58 to 32%), cystoscopy for patients Stage IIB and higher (64 to 52%), and lymphangiography (18 to 14%). The use of abdominal or pelvic computed tomography dramatically increased from 6 to 70% between the first and third surveys. The use of 60Co units decreased from 35 to 2% from the first to the third survey [6 to 0% for short source-surface distance (SSD) 60Co units]. Point dose calculations for the intracavitary therapy increased from 78% in the 1978 survey to 95% in the third survey. As determined by the total dose delivered to the paracentral points, more patients (75.1%) were treated according to the Patterns of Care recommended guidelines in the 1988-89 survey than in the 1983 survey (63.6%). Chemotherapy was given to 12% of the patients undergoing radiation therapy during the period of the third survey, but these data are not available for the first and second surveys. CONCLUSION Review of the Carcinoma of the Cervix Patterns of Care studies discloses significant changes in the demographics, patient evaluation, and radiation therapy techniques during the period of the studies. The potential impact of these changes on treatment outcome cannot be determined at this time until longterm follow-up for the 1988-89 survey is available, but improvements in the processes of care should lead to improvements in outcome.

Outcome Results of the 1996-1999 Patterns of Care Survey of the National Practice for Patients Receiving Radiation Therapy for Carcinoma of the Esophagus

Purpose A Patterns of Care Study of patients treated from 1996 to 1999 evaluated the national practice for patients receiving radiation therapy for carcinoma of the esophagus in the United States. Methods A national survey was conducted at 59 institutions in a stratified random sample selected from a master list of radiation therapy facilities throughout the United States. Patient, tumor, and treatment characteristics were evaluated. Multivariate comparisons of survival times were made using the Cox proportional hazards model. Results Adenocarcinoma was diagnosed in 51% of patients and squamous cell carcinoma in 49% of patients. Sixteen percent of patients were clinical stage (CS) I (using the 1983 American Joint Committee on Cancer system), 39% were CS II, and 33% were CS III. Significant variables in the multivariate analysis of survival times included clinical stage, treatment approach, and facility size. Patients with CS III disease had a higher hazard risk of death as compared with CS I patients (haz...