DEGRO practical guideline for partial-breast irradiation.

PURPOSE: This consensus statement from the Breast Cancer Working Group of the German Society for Radiation Oncology (DEGRO) aims to define practical guidelines for accelerated partial-breast irradiation (APBI). METHODS: Recent recommendations for relevant aspects of APBI were summarized and a panel of experts reviewed all the relevant literature. Panel members of the DEGRO experts participated in a series of conferences, supplemented their clinical experience, performed a literature review, and formulated recommendations for implementing APBI in clinical routine, focusing on patient selection, target definition, and treatment technique. RESULTS: Appropriate patient selection, target definition for different APBI techniques, and basic rules for appropriate APBI techniques for clinical routine outside of clinical trials are described. Detailed recommendations for APBI in daily practice, including dose constraints, are given. CONCLUSION: Guidelines are mandatory to assure optimal results of APBI using different techniques.

DEGRO practical guidelines: radiotherapy of breast cancer II: radiotherapy of non-invasive neoplasia of the breast.

PURPOSE: To complement and update the 2007 practice guidelines of the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO) for radiotherapy (RT) of breast cancer. Owing to its growing clinical relevance, in the current version, a separate paper is dedicated to non-invasive proliferating epithelial neoplasia of the breast. In addition to the more general statements of the German interdisciplinary S3 guidelines, this paper is especially focused on indication and technique of RT in addition to breast conserving surgery. METHODS: The DEGRO expert panel performed a comprehensive survey of the literature comprising recently published data from clinical controlled trials, systematic reviews as well as meta-analyses, referring to the criteria of evidence-based medicine yielding new aspects compared to 2005 and 2007. The literature search encompassed the period 2008 to September 2012 using databases of PubMed and Guidelines International Network (G-I-N). Search terms were "non invasive breast cancer", "ductal carcinoma in situ, "dcis", "borderline breast lesions", "lobular neoplasia", "radiotherapy" and "radiation therapy". In addition to the more general statements of the German interdisciplinary S3 guidelines, this paper is especially focused on indications of RT and decision making of non-invasive neoplasia of the breast after surgery, especially ductal carcinoma in situ. RESULTS: Among different non-invasive neoplasia of the breast only the subgroup of pure ductal carcinoma in situ (DCIS; synonym ductal intraepithelial neoplasia, DIN) is considered for further recurrence risk reduction treatment modalities after complete excision of DCIS, particularly RT following breast conserving surgery (BCS), in order to avoid a mastectomy. About half of recurrences are invasive cancers. Up to 50 % of all recurrences require salvage mastectomy. Randomized clinical trials and a huge number of mostly observational studies have unanimously demonstrated that RT significantly reduces recurrence risks of ipsilateral DCIS as well as invasive breast cancer independent of patient age in all subgroups. The recommended total dose is 50 Gy administered as whole breast irradiation (WBI) in single fractions of 1.8 or 2.0 Gy given on 5 days weekly. Retrospective data indicate a possible beneficial effect of an additional tumor bed boost for younger patients. Prospective clinical trials of different dose-volume concepts (hypofractionation, accelerated partial breast irradiation, boost radiotherapy) are still ongoing. CONCLUSION: Postoperative radiotherapy permits breast conservation for the majority of women by halving local recurrence as well as reducing progression rates into invasive cancer. New data confirmed this effect in all patient subsets-even in low risk subgroups (LoE 1a).

DEGRO practical guidelines: radiotherapy of breast cancer III--radiotherapy of the lymphatic pathways.

AIM: The purpose of this work is to update the practical guidelines for adjuvant radiotherapy of the regional lymphatics of breast cancer published in 2008 by the breast cancer expert panel of the German Society of Radiation Oncology (DEGRO). METHODS: A comprehensive survey of the literature concerning regional nodal irradiation (RNI) was performed using the following search terms: "breast cancer", "radiotherapy", "regional node irradiation". Recent randomized trials were analyzed for outcome as well as for differences in target definition. Field arrangements in the different studies were reproduced and superimposed on CT slices with individually contoured node areas. Moreover, data from recently published meta-analyses and guidelines of international breast cancer societies, yielding new aspects compared to 2008, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the German interdisciplinary S3 guidelines updated in 2012, this paper addresses indications, targeting, and techniques of radiotherapy of the lymphatic pathways after surgery for breast cancer. RESULTS: International guidelines reveal substantial differences regarding indications for RNI. Patients with 1-3 positive nodes seem to profit from RNI compared to whole breast (WBI) or chest wall irradiation alone, both with regard to locoregional control and disease-free survival. Irradiation of the regional lymphatics including axillary, supraclavicular, and internal mammary nodes provided a small but significant survival benefit in recent randomized trials and one meta-analysis. Lymph node irradiation yields comparable tumor control in comparison to axillary lymph node dissection (ALND), while reducing the rate of lymph edema. Data concerning the impact of 1-2 macroscopically affected sentinel node (SN) or microscopic metastases on prognosis are conflicting. CONCLUSION: Recent data suggest that the current restrictive use of RNI should be scrutinized because the risk-benefit relationship appears to shift towards an improvement of outcome.

DEGRO practical guidelines: radiotherapy of breast cancer I: radiotherapy following breast conserving therapy for invasive breast cancer.

BACKGROUND AND PURPOSE: The aim of the present paper is to update the practical guidelines for postoperative adjuvant radiotherapy of breast cancer published in 2007 by the breast cancer expert panel of the German Society for Radiooncology (Deutsche Gesellschaft für Radioonkologie, DEGRO). The present recommendations are based on a revision of the German interdisciplinary S-3 guidelines published in July 2012. METHODS: A comprehensive survey of the literature concerning radiotherapy following breast conserving therapy (BCT) was performed using the search terms "breast cancer", "radiotherapy", and "breast conserving therapy". Data from lately published meta-analyses, recent randomized trials, and guidelines of international breast cancer societies, yielding new aspects compared to 2007, provided the basis for defining recommendations according to the criteria of evidence-based medicine. In addition to the more general statements of the DKG (Deutsche Krebsgesellschaft), this paper addresses indications, target definition, dosage, and technique of radiotherapy of the breast after conservative surgery for invasive breast cancer. RESULTS: Among numerous reports on the effect of radiotherapy during BCT published since the last recommendations, the recent EBCTCG report builds the largest meta-analysis so far available. In a 15 year follow-up on 10,801 patients, whole breast irradiation (WBI) halves the average annual rate of disease recurrence (RR 0.52, 0.48-0.56) and reduces the annual breast cancer death rate by about one sixth (RR 0.82, 0.75-0.90), with a similar proportional, but different absolute benefit in prognostic subgroups (EBCTCG 2011). Furthermore, there is growing evidence that risk-adapted dose augmentation strategies to the tumor bed as well as the implementation of high precision RT techniques (e.g., intraoperative radiotherapy) contribute substantially to a further reduction of local relapse rates. A main focus of ongoing research lies in partial breast irradiation strategies as well as WBI hypofractionation schedules. The potential of both in replacing normofractionated WBI has not yet been finally clarified. CONCLUSION: After breast conserving surgery, no subgroup even in low risk patients has yet been identified for whom radiotherapy can be safely omitted without compromising local control and, hence, cancer-specific survival. In most patients, this translates into an overall survival benefit.

Reproducibility of the CROSS Trial Results in the Multimodal Treatment of Esophageal Cancer in Daily Practice: A Single Center Retrospective Observational Study.

Background: Treatment of nonmetastatic esophageal cancer with curative intention remains a major challenge. Neoadjuvant radiochemotherapy followed by surgery, as described in the CROSS trial in 2012, has been established as a standard of care. With this retrospective observational study, we aimed to analyze the results of the CROSS regimen in daily practice over the last 10 years at the St. Clara Hospital, a Swiss center for esophageal surgery. Methods: To determine the clinical outcome in our daily practice, the medical records of all patients with potentially curable localized esophageal cancer (T1N1 or T2-3N0-1 M0) treated with radiochemotherapy in neoadjuvant intention according to the CROSS regimen were reviewed. The primary endpoint was overall survival. Furthermore, an overall survival analysis of the subgroups of patients who exactly met the inclusion criteria of the CROSS trial with respect to age and weight loss before therapy was performed. The Kaplan-Meier method was used to estimate survival and compared by the log-rank test. Results: From January 2012 to January 2022, 91 patients with T1N1 or T2-3N0-1M0 esophageal cancer underwent neoadjuvant radiochemotherapy according to the CROSS regimen. The median age was 70 years (range 31-86 years), and 26 (29%) patients were over 75 years of age. Weight loss of more than 10% was observed in 23 (25%) patients. 77 (85%) patients underwent esophagectomy, and complete resection (R0) was obtained in 73 (95%) of them. The median overall survival was 41 months, compared to 49.4 months in the CROSS trial. The overall survival rate at 12 months was 85% and at 24 months, it was 68%, very similar to the CROSS trial results. 51% of the patients fully met the inclusion criteria of the CROSS trial with respect to age and pretherapeutic weight loss. Their overall survival rate at 12 months was 94% at St. Clara Hospital versus 82% in the CROSS trial (p=0.04), and at 24 months, 81% versus 67% (p=0.05). Conclusion: Overall, in a center specialized for the multimodal treatment of nonmetastatic esophageal cancer, the results of the CROSS trial seem to be well reproducible in daily practice.

When are breast cancer patients old enough for the quitclaim of local control?

BACKGROUND: Although postoperative radiotherapy (RT) after breast-conserving surgery (BCS) halves the 10-year recurrence rate in breast cancer patients through all age groups, the question of whether RT may be omitted and replaced by endocrine therapy for women aged 70 years and older with low-risk factors has recently become an issue of debate. METHODS: Survey of the relevant recent literature (Medline) and international guidelines. RESULTS: Three randomized studies investigating the effect of RT in older women revealed significantly increased local recurrence rates when RT was omitted, and a negative impact on disease-free survival was observed in two of these trials. Despite these findings, in one of the studies omission of RT in women over 70 is recommended, leading to a respective amendment in the guidelines of the American National Comprehensive Cancer Network. Several large retrospective cohort studies analyzing the outcome of patients over 65 years with and without RT have since been published and showed a significantly improved local control in all subgroups of advanced age and stage, which predominantly translated into improved disease-free and overall survival. CONCLUSION: No subgroup of elderly patients has yet been identified that did not profit from RT in terms of local control. Therefore, chronological age alone is not an appropriate criterion for deciding against or in favor of adjuvant RT. The DEGRO breast cancer expert panel explicitly discourages determination of a certain age for the omission of postoperative RT in healthy elderly women with low-risk breast cancer. For frail elderly women, treatment decisions should be individually decided on the basis of standardized geriatric assessment.

Prescribed fire: effects on water quality and forest nutrient cycling.

Prescribed fire, a practice applied annually to about 10(6) hectares of forests in the southeastern United States, had limited effects on soils, nutrient cycling, and hydrologic systems of a coastal plain pine forest. Hydrologic fluxes of nitrogen, phosphorus, sulfur, and basic cations, from burned pine litter to ground and stream waters, are not likely to have appreciable impacts on water quality in the Atlantic and Gulf Coastal Plain.

THE GERMAN DOSE RATE MONITORING NETWORK AND IMPLEMENTED DATA HARMONIZATION TECHNIQUES.

Environmental radiation monitoring networks have been established in Europe and world-wide for the purpose of protecting population and environment against ionizing radiation. Some of these networks had been established during the cold war period and were improved after the Chernobyl accident in 1986. Today, the German Federal Office for Radiation Protection (BfS) operates an early warning network with roughly 1800 ambient dose equivalent rate (ADER) stations equally distributed over the German territory. The hardware and software of all network components are developed in-house allowing the continuous optimization of all relevant components. A probe characterization and quality assurance and control program are in place. Operational and technical aspects of the network and data harmonization techniques are described. The latter allows for calculating of the terrestrial and net ADER combined with uncertainties mainly from site specific effects. Harmonized data are finally used as input to the German emergency management system and the European radiological data exchange platform.

Daytime pulsed dose rate brachytherapy as a new treatment option for previously irradiated patients with recurrent oesophageal cancer.

The aim of this study was to evaluate the feasibility, effects, and toxicity of pulsed dose rate (PDR) brachytherapy for re-irradiation of oesophageal carcinoma. A total of 16 patients (median age 67 years) with inoperable recurrences from oesophageal cancer after primary radio-(chemo)-therapy (median 50 Gy) were re-irradiated using PDR brachytherapy ((192)Ir, 37 GBq). Treatment was carried out on an outpatient basis applying a weekly 5 Gy daytime schedule (0.5 Gy pulse(-1) h(-1), total dose 15-20 Gy). The dose was prescribed 10 mm from the mid-dwell position and encompassed the clipped tumour extension with 2 cm margins. The use of clips for delineation of tumour extent and catheter movement during irradiations was evaluated. All 61 PDR treatments were applied safely. The median catheter movement was 5 mm, range 2-12 mm. After a median follow-up of 8 months, three patients had a complete and five a partial remission. Body weight increased in 5 of 16 (31%) and was stable in 4 of 16 (25%) patients, respectively. The median grade 2 (RTOG/EORTC) dysphagia-free survival was 17 months. Seven patients experienced grade 1, five grade 2, and one grade 3 late toxicity. Three patients with uncontrolled locoregional disease showed grade 4 complications (oesophago-tracheal fistulae (n=2), fatal arterial bleeding (n=1). Daytime PDR brachytherapy proved to be feasible and provided effective palliation. Toxicity remains a major problem. Thus, total dose should be restricted to <15 Gy in this palliative situation.

Abutment of high energy electron fields.

The problem of positioning multiple electron fields on the skin surface is complicated by the fact that the scattering properties of electrons result in constriction of the higher value isodoses and bulging out of the lower value isodoses. We have studied the dose distributions in the junction region for adjacent electron fields using our 3-dimensional radiation treatment planning system by investigating the effects of field separation for several field size, air gap, and beam energy combinations. Film dosimetry was used to measure specific test cases. Using our 3-dimensional radiation treatment planning system, we are able to display the calculated dose distribution, calculate dose-volume histograms, and compare calculations with the film dosimetry measurements. Results of our study are presented.

Independent collimator dosimetry for a dual photon energy linear accelerator.

PURPOSE: The independent collimator feature in medical linear accelerators can define radiation fields that are asymmetric with respect to the flattening filter and oblique to the incident surface. Prior to clinical implementation, it is necessary to evaluate the dosimetry of this non-standard treatment delivery technique. An investigation of the independent collimator dosimetry for 6 MV and 18 MV x-ray beams has been undertaken. METHODS AND MATERIALS: Dose to tissue in free space, percent depth dose and dose distribution were measured and compared to that for symmetric field collimation. RESULTS: The dosimetry results were consistent for both photon modes. Dose in free space with asymmetric collimation can be calculated from the corresponding symmetric field dose in free space to within 1.2 +/- 0.7% by applying an appropriate off-axis factor. Asymmetric field percent depth dose differs from symmetric field percent depth dose on average by 1.1 +/- 0.7% for 6 MV and by 0.7 +/- 0.5% for 18 MV for field sizes ranging from 5 x 5 to 20 x 20, centered 3 cm and 10 cm off-axis. The measured isodose curves demonstrate divergence effects and reduced doses (less than 3%) adjacent to the field edge closest to the flattening filter center. This dose asymmetry result is identical to that from secondary collimation. CONCLUSION: The methodology for clinical implementation of the independent collimator feature is straightforward. However, accurate representation of the isodose distributions by commercial radiotherapy treatment planning systems requires special dose calculation algorithms.

Clinical implementation of a commercial multileaf collimator: dosimetry, networking, simulation, and quality assurance.

PURPOSE: Clinical implementation of multileaf collimation (MLC) includes commissioning (including leaf calibration), dosimetric measurements (penumbra, transmission, calculation parameters), shaping methods, networking for file transfer, verification simulation, and development of a quality assurance (QA) program. Differences of MLC and alloy shaping in terms of penumbra and stair-step effects must be analyzed. METHODS AND MATERIALS: Leaf positions are calibrated to light field. The resultant decrement line, penumbras, leaf transmission data, and isodoses in various planes were measured with film. Penumbra was measured for straight edges and corners, in various media. Ion chambers were used to measure effects of MLC on output, scatter, and depth dose. We maintain midleaf intersection criteria. MLC fields are set 7 mm beyond planning target volumes. After shaping by vendor software or by our three-dimensional planning system, files are transferred to the MLC workstation by means of sharing software, interface cards, and cabling. A MLC emulator was constructed for simulation. Our QA program includes file checks, monthly checks (leaf position accuracy and interlock tests), and annual review. RESULTS: We found the MLC leaf position (light field) corresponds to decrement lines ranging from 50 to 59%. Transmission through MLC (1.5-2.5%) is less than alloy (3.5%). Multileaf penumbra is slightly wider than for alloy. Relative penumbra did not increase in the lung, and composite field dosimetry exhibited negligible differences compared with alloy. Verification simulations provide diagnostic image quality hard copies of the MLC fields. Monitor unit parameters used for alloy held for MLC. DISCUSSION: Clinical implementation for MLC as a block replacement was conducted on a site-by-site basis. Time studies indicate significant (25%) in-room time reductions. Through imaging and dosimetric analysis, the accuracy of field delivery has increased with MLC. The most significant impact of MLC is the ability to increase the number of daily treatment fields, thereby reducing normal tissue dosing, which is vital for dose escalation.

The cumulative verification image analysis tool for offline evaluation of portal images.

PURPOSE: Daily portal images acquired using electronic portal imaging devices contain important information about the setup variation of the individual patient. The data can be used to evaluate the treatment and to derive correction for the individual patient. The large volume of images also require software tools for efficient analysis. This article describes the approach of cumulative verification image analysis (CVIA) specifically designed as an offline tool to extract quantitative information from daily portal images. METHODS AND MATERIALS: The user interface, image and graphics display, and algorithms of the CVIA tool have been implemented in ANSCI C using the X Window graphics standards. The tool consists of three major components: (a) definition of treatment geometry and anatomical information; (b) registration of portal images with a reference image to determine setup variation; and (c) quantitative analysis of all setup variation measurements. The CVIA tool is not automated. User interaction is required and preferred. Successful alignment of anatomies on portal images at present remains mostly dependent on clinical judgment. Predefined templates of block shapes and anatomies are used for image registration to enhance efficiency, taking advantage of the fact that much of the tool's operation is repeated in the analysis of daily portal images. RESULTS: The CVIA tool is portable and has been implemented on workstations with different operating systems. Analysis of 20 sequential daily portal images can be completed in less than 1 h. The temporal information is used to characterize setup variation in terms of its systematic, random and time-dependent components. The cumulative information is used to derive block overlap isofrequency distributions (BOIDs), which quantify the effective coverage of the prescribed treatment area throughout the course of treatment. Finally, a set of software utilities is available to facilitate feedback of the information for treatment plan recalculation and to test various decision strategies for treatment adjustment. CONCLUSIONS: The CVIA tool provides comprehensive analysis of daily images acquired with electronic portal imaging devices. Its offline approach allows characterization of the nature of setup variation for the individual patient that would have been difficult to deduce using only a few daily or weekly portal images. Distribution of the tool will help establish an important database of setup variation from many clinics. The information derived from CVIA can also serve as the foundation to integrate treatment verification, treatment planning, and treatment delivery.

Three dimensional conformal radiation therapy in pediatric parameningeal rhabdomyosarcomas.

PURPOSE: We evaluated the utility of three dimensional (3D) treatment planning in the management of children with parameningeal head and neck rhabdomyosarcomas. METHODS AND MATERIALS: Five children with parameningeal rhabdomyosarcoma were referred for treatment at our radiation oncology center from May 1990 through January 1993. Each patient was evaluated, staged, and treated according to the Intergroup Rhabdomyosarcoma Study. Patients were immobilized and underwent a computed tomography scan with contrast in the treatment position. Tumor and normal tissues were identified with assistance from a diagnostic radiologist and defined in each slice. The patients were then planned and treated with the assistance of a 3D treatment planning system. A second plan was then devised by another physician without the benefit of the 3D volumetric display. The target volumes designed with the 3D system and the two-dimensional (2D) method were then compared. The dosimetric coverage to tumor, tumor plus margin, and normal tissues was also compared with the two methods of treatment planning. RESULTS: The apparent size of the gross tumor volume was underestimated with the conventional 2D planning method relative to the 3D method. When margin was added around the gross tumor to account for microscopic extension of disease in the 2D method, the expected area of coverage improved relative to the 3D method. In each circumstance, the minimum dose that covered the gross tumor was substantially less with the 2D method than with the 3D method. The inadequate dosimetric coverage was especially pronounced when the necessary margin to account for subclinical disease was added. In each case, the 2D plans would have delivered substantial dose to adjacent normal tissues and organs, resulting in a higher incidence of significant complications. CONCLUSIONS: 3D conformal radiation therapy has a demonstrated advantage in the treatment of sarcomas of the head and neck. The improved dosimetric coverage of the tumor and its margin for subclinical extensions may result in improvement in local control of these tumors. In addition, lowering of radiation dose to adjacent critical structures may help lower the incidence of adverse late effects in children.

Preliminary results of a prospective trial using three dimensional radiotherapy for lung cancer.

PURPOSE: To evaluate the preliminary results of a prospective trial using three-dimensional (3D) treatment for lung cancer. METHODS AND MATERIALS: Seventy patients with inoperable Stage I through IIIB lung cancer were treated with three-dimensional thoracic irradiation with or without chemotherapy (35% received chemotherapy). Total prescribed dose to the tumor ranged from 60-74 Gy (uncorrected for lung density). All patients were evaluated for local control, survival, and development of pneumonitis. These parameters were evaluated in respect to and compared with three-dimensional parameters used in their treatment planning. RESULTS: With a minimum follow-up of 6 to 30 months, the 2-year cause-specific survival rate for Stages I and II was 90% and 53% for Stage III (no difference between Stages IIIA and IIIB). Patients with local tumor control had a better 2-year overall survival rate (47%) than those with local failure (31%). Volumetrically heterogeneously calculated doses were important to the accurate delineation of dose-volume coverage as there was a wide range of discrepancies between a homogeneously prescribed point dose calculation and the heterogeneously calculated volume coverage of that prescription. High-grade pneumonitis was correlated with the location of the tumor with lower lobe tumors having a much higher risk than those with upper lobe tumors. A critical volume effect and threshold dose were apparent in the development of high-grade pneumonitis. CONCLUSIONS: Three-dimensional therapy for lung cancer has been practically implemented at the Mallinckrodt Institute of Radiology and shows promising results in our preliminary analysis. The incidence of high-grade pneumonitis, however, warrants careful selection of patients for future dose escalation. Future dose escalation trials in lung cancer should be directed to volumes that limit the amount of elective nodal irradiation. However, the volume of necessary elective nodal irradiation remains unknown and should be studied prospectively. Dose escalation trials are indicated and may be facilitated by smaller target volumes.