Oligometastasis in breast cancer-current status and treatment options from a radiation oncology perspective.

Evidence from a few small randomized trials and retrospective cohorts mostly including various tumor entities indicates a prolongation of disease free survival (DFS) and overall survival (OS) from local ablative therapies in oligometastatic disease (OMD). However, it is still unclear which patients benefit most from this approach. We give an overview of the several aspects of stereotactic body radiotherapy (SBRT) in extracranial OMD in breast cancer from a radiation oncology perspective. A PubMed search referring to this was conducted. An attempt was made to relate the therapeutic efficacy of SBRT to various prognostic factors. Data from approximately 500 breast cancer patients treated with SBRT for OMD in mostly in small cohort studies have been published, consistently indicating high local tumor control rates and favorable progression-free (PFS) and overall survival (OS). Predictors for a good prognosis after SBRT are favorable biological subtype (hormone receptor positive, HER2 negative), solitary metastasis, bone-only metastasis, and long metastasis-free interval. However, definitive proof that SBRT in OMD breast cancer prolongs DFS or OS is lacking, since, with the exception of one small randomized trial (n = 22 in the SBRT arm), none of the cohort studies had an adequate control group. Further studies are needed to prove the benefit of SBRT in OMD breast cancer and to define adequate selection criteria. Currently, the use of local ablative SBRT should always be discussed in a multidisciplinary tumor board.

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.

Quality assurance guidelines for interstitial hyperthermia.

Quality assurance (QA) guidelines are essential to provide uniform execution of clinical hyperthermia treatments and trials. This document outlines the clinical and technical consequences of the specific properties of interstitial heat delivery and specifies recommendations for hyperthermia administration with interstitial techniques. Interstitial hyperthermia aims at tumor temperatures in the 40-44 °C range as an adjunct to radiation or chemotherapy. The clinical part of this document imparts specific clinical experience of interstitial heat delivery to various tumor sites as well as recommended interstitial hyperthermia workflow and procedures. The second part describes technical requirements for quality assurance of current interstitial heating equipment including electromagnetic (radiative and capacitive) and ultrasound heating techniques. Detailed instructions are provided on characterization and documentation of the performance of interstitial hyperthermia applicators to achieve reproducible hyperthermia treatments of uniform high quality. Output power and consequent temperature rise are the key parameters for characterization of applicator performance in these QA guidelines. These characteristics determine the specific maximum tumor size and depth that can be heated adequately. The guidelines were developed by the ESHO Technical Committee with participation of senior STM members and members of the Atzelsberg Circle.

Multicatheter interstitial brachytherapy for breast cancer.

Brachytherapy remains the best irradiation technique to deliver a high dose in a small volume. Breast brachytherapy is part of the arsenal of therapy in the management of breast cancer. In this article, we present the technical data related to multicatheter interstitial brachytherapy to the breast proceeding, from the implantation of the vectors to the treatment itself. The indications for brachytherapy in breast cancer are boost after whole breast irradiation, accelerated partial breast irradiation or selected patients with second ipsilateral breast tumor event. The results in terms of efficacy and toxicity are presented for each indication. Multicatheter interstitial breast brachytherapy remains a major technique for breast cancer treatment.

A tool to automatically analyze electromagnetic tracking data from high dose rate brachytherapy of breast cancer patients.

During High Dose Rate Brachytherapy (HDR-BT) the spatial position of the radiation source inside catheters implanted into a female breast is determined via electromagnetic tracking (EMT). Dwell positions and dwell times of the radiation source are established, relative to the patient's anatomy, from an initial X-ray-CT-image. During the irradiation treatment, catheter displacements can occur due to patient movements. The current study develops an automatic analysis tool of EMT data sets recorded with a solenoid sensor to assure concordance of the source movement with the treatment plan. The tool combines machine learning techniques such as multi-dimensional scaling (MDS), ensemble empirical mode decomposition (EEMD), singular spectrum analysis (SSA) and particle filter (PF) to precisely detect and quantify any mismatch between the treatment plan and actual EMT measurements. We demonstrate that movement artifacts as well as technical signal distortions can be removed automatically and reliably, resulting in artifact-free reconstructed signals. This is a prerequisite for a highly accurate determination of any deviations of dwell positions from the treatment plan.

On the use of particle filters for electromagnetic tracking in high dose rate brachytherapy.

Modern radiotherapy of female breast cancers often employs high dose rate brachytherapy, where a radioactive source is moved inside catheters, implanted in the female breast, according to a prescribed treatment plan. Source localization relative to the patient's anatomy is determined with solenoid sensors whose spatial positions are measured with an electromagnetic tracking system. Precise sensor dwell position determination is of utmost importance to assure irradiation of the cancerous tissue according to the treatment plan. We present a hybrid data analysis system which combines multi-dimensional scaling with particle filters to precisely determine sensor dwell positions in the catheters during subsequent radiation treatment sessions. Both techniques are complemented with empirical mode decomposition for the removal of superimposed breathing artifacts. We show that the hybrid model robustly and reliably determines the spatial positions of all catheters used during the treatment and precisely determines any deviations of actual sensor dwell positions from the treatment plan. The hybrid system only relies on sensor positions measured with an EMT system and relates them to the spatial positions of the implanted catheters as initially determined with a computed x-ray tomography.

On the use of multi-dimensional scaling and electromagnetic tracking in high dose rate brachytherapy.

High dose rate brachytherapy affords a frequent reassurance of the precise dwell positions of the radiation source. The current investigation proposes a multi-dimensional scaling transformation of both data sets to estimate dwell positions without any external reference. Furthermore, the related distributions of dwell positions are characterized by uni-or bi-modal heavy-tailed distributions. The latter are well represented by α-stable distributions. The newly proposed data analysis provides dwell position deviations with high accuracy, and, furthermore, offers a convenient visualization of the actual shapes of the catheters which guide the radiation source during the treatment.

High Dose Rate Brachytherapy as Monotherapy for Localised Prostate Cancer: Review of the Current Status.

The aim of this article is to review and present the published data on high dose rate (HDR) brachytherapy as monotherapy in the treatment of localised prostate cancer. A search and review of the literature was carried out on PubMed and MedLine using the medical subject headings 'high-dose-rate, brachytherapy, prostate cancer, monotherapy' as search terms. The search yielded more than 100 articles and abstracts published between 2000 and 2016. Only original clinical data on HDR monotherapy reporting oncological outcomes were included. When more than one series from the same institution were identified, the most recent one encompassing the largest patient number was considered for analysis. For citation crosscheck, the ISI web of science database was used employing the same search terms. Data tables were generated and summary descriptions created. The main outcome parameters used were biochemical control and toxicity scores. Fifteen articles comprising 3546 patients reported clinical outcome and toxicity, with follow-up ranging from median 1.4 to 8.0 years. A variety of dose and fractionation schedules were described, including 19.0 Gy as a single fraction to 54.0 Gy in nine fractions. Biochemical control rates ranged from 66 to 100% in low-risk, 63 to 98% in intermediate-risk and 81-93% in high-risk patients. Late grade 3 genitourinary and gastrointestinal toxicity was 0-16% and 0-2%, respectively. The reported potency preservation rates ranged from 60 to 90%. In conclusion, high biochemical control and low complication rates are reported with HDR monotherapy. It is a safe and effective local treatment modality for organ-confined prostate cancer with reproducible high-quality dosimetry.

Re-irradiation of the chest wall for local breast cancer recurrence : Results of salvage brachytherapy with hyperthermia.

AIM: Following mastectomy and adjuvant external beam radiation therapy in patients with breast cancer, the incidence of local or locoregional recurrence is approximately 9 % (2-20 %). Alongside the often limited possibilities of surgical treatment, radiation therapy combined with superficial hyperthermia is the most effective local therapy. In the present work, a retrospective analysis of salvage brachytherapy combined with superficial hyperthermia for chest wall recurrences is presented. PATIENTS AND METHODS: Between 2004 and 2011, 18 patients with a total of 23 target volumes resulting from chest wall recurrences after previously mastectomy and external beam radiation therapy (median 56 Gy, range 50-68 Gy) were treated with superficial brachytherapy as salvage treatment: 8 patients (44 %) had macroscopic tumor, 3 (17 %) had microscopic tumor (R1), and 7 (39 %) had undergone R0 resection and were treated due to risk factors. A dose of 50 Gy was given (high-dose rate [HDR] and pulsed-dose rate [PDR] procedures). In all, 5 of 23 patients (22 %) received additional concurrent chemotherapy, and in 20 of 23 (87 %) target volumes additional superficial hyperthermia was carried out twice weekly. RESULTS: The 5­year local recurrence-free survival was 56 %, the disease-free survival was 28 %, and a 5-year overall survival was 22 %. Late side effects Common Toxicity Criteria (CTC) grade 3 were reported in 17 % of the patients: 2 of 18 (11 %) had CTC grade 3 fibrosis, and 1 of 18 (6 %) had a chronic wound healing disorder. CONCLUSION: Re-irradiation as salvage brachytherapy with superficial hyperthermia for chest wall recurrences is a feasible and safe treatment with good local control results and acceptable late side effects.

Time and Resources Needed to Document Patients with Breast Cancer from Primary Diagnosis to Follow-up - Results of a Single-center Study.

Aim: Certification of breast centers helps improve the quality of care but requires additional resources, particularly for documentation. There are currently no published data on the actual staff costs and financial resources required for such documentation. The aim of this study was to determine the time and resources required to document a patient with primary breast cancer from diagnosis to the end of follow-up, to establish a database for future strategic decisions. Material and Methods: All diagnostic and therapeutic procedures of patients with primary breast cancer were recorded at the University Breast Center of Franconia. All time points for documentation were evaluated using structured interviews. The times required to document a representative number of patients were determined and combined with the staff costs of the different professional groups, to calculate the financial resources required for documentation. Results: A total of 494 time points for documentation were identified. The study also identified 21 departments and 20 different professional groups involved in the documentation. The majority (54 %) of documentation was done by physicians. 62 % of all documentation involved outpatients. The results of different scenarios for the diagnosis, therapy and follow-up of breast cancer patients in a certified breast center showed that the time required for documentation can be as much as 105 hours, costing € 4135. Conclusion: This analysis shows the substantial staffing and financial costs required for documentation in certified centers. A multi-center study will be carried out to compare the costs for certified breast centers of varying sizes with the costs of non-certified care facilities.

Protocol-based image-guided salvage brachytherapy. Early results in patients with local failure of prostate cancer after radiation therapy.

PURPOSE: To assess the overall clinical outcome of protocol-based image-guided salvage pulsed-dose-rate brachytherapy for locally recurrent prostate cancer after radiotherapy failure particularly regarding feasibility and side effects. PATIENTS AND METHODS: Eighteen consecutive patients with locally recurrent prostate cancer (median age, 69 years) were treated during 2005-2011 with interstitial PDR brachytherapy (PDR-BT) as salvage brachytherapy after radiotherapy failure. The treatment schedule was PDR-BT two times with 30 Gy (pulse dose 0.6 Gy/h, 24 h per day) corresponding to a total dose of 60 Gy. Dose volume adaptation was performed with the aim of optimal coverage of the whole prostate (V100 > 95 %) simultaneously respecting the protocol-based dose volume constraints for the urethra (D0.1 cc < 130 %) and the rectum (D2 cc < 50-60 %) taking into account the previous radiation therapy. Local relapse after radiotherapy (external beam irradiation, brachytherapy with J-125 seeds or combination) was confirmed mostly via choline-PET and increased PSA levels. The primary endpoint was treatment-related late toxicities--particularly proctitis, anal incontinence, cystitis, urinary incontinence, urinary frequency/urgency, and urinary retention according to the Common Toxicity Criteria. The secondary endpoint was PSA-recurrence-free survival. RESULTS: We registered urinary toxicities only. Grade 2 and grade 3 toxicities were observed in up to 11.1 % (2/18) and 16.7 % (3/18) of patients, respectively. The most frequent late-event grade 3 toxicity was urinary retention in 17 % (3/18) of patients. No late gastrointestinal side effects occurred. The biochemical PSA-recurrence-free survival probability at 3 years was 57.1 %. The overall survival at 3 years was 88.9 %; 22 % (4/18) of patients developed metastases. The median follow-up time for all patients after salvage BT was 21 months (range, 8-77 months). CONCLUSION: Salvage PDR-brachytherapy of the prostate following local failure after radiation therapy is a treatment option with a low rate of genitourinary side effects and no late gastrointestinal side effects. The treatment efficacy in the first 3 years is promising.

[Brachytherapy for the treatment of head and neck cancer]. / Brachytherapie für die Behandlung von Kopf-Hals-Karzinomen.

Image-Adapted brachytherapy (IABT) is a modern interdisciplinary development of classic radiation therapy, which allows the application of a high radiation dose while avoiding severe adverse events, thereby improving the prognosis of our patients. Indications in head and neck squamous cell carcinoma (HNSCC) include tumours of the floor of mouth, the face, the paranasal sinuses, the naso- and oropharynx, recurrent cancer and incomplete resections due to close vicinity of the tumor to important structures. The application type can be classified as curative, adjuvant, perioperative as a boost with or without external beam radiation (EBRT) or as a palliative treatment. The published results encourage the integration of IABT as part of the therapy of HNSCC, thereby improving the prognosis and quality of life of our patients.

[High-dose 106Ruthenium plaque brachytherapy for posterior uveal melanoma. A clinico-pathologic study]. / Hochdosisbrachytherapie des malignen Aderhaut- und Ziliarkörpermelanoms mit 106Ruthenium. Eine klinisch-pathologische Studie.

BACKGROUND: The purpose of this study was to report the multifactorial results of high-dose (106)Ruthenium plaque brachytherapy for (cilio-)choroidal melanoma and to confirm them by histological examinations. PATIENTS AND METHODS: 100 patients with choroidal or ciliochoroidal melanoma treated by high-dose 106Ruthenium plaque brachytherapy were followed-up for 5 years. 12 secondary enucleated eyes were compared to a non-irradiated matched group by light microscopy. RESULTS: The 5-year local tumour control rate was 93%, the 5-year survival rate 91%. Late radiogenic side effects occured as a retinopathy in 13%, as an optic neuropathy in 5% and as a secondary glaucoma in 3% of the patients. 14% had to be enucleated, 10% developed metastases. The histopathologic examination revealed significantly higher degrees of necrosis (p=0,041), balloon cell degeneration (p=0,025) and fibrosis (p<0,001) in the irradiated melanomas than in the control tumours. CONCLUSION: High-dose 106Ruthenium plaque brachytherapy turned out to be an effective treatment procedure for posterior uveal melanoma (not exceeding a prominence of 5,5 mm) with a high rate of local tumour control and a low rate of side effects.

[Partial breast irradiation for early breast cancer with favorable prognostic factors: 3-year results of the German-Austrian phase II-trial]. / Teilbrustbestrahlung beim Mammakarzinom mit günstigen prognostischen Faktoren: 3-Jahres-Ergebnisse der deutsch-österreichischen Phase II-Studie.

PURPOSE: To evaluate perioperative morbidity, toxicity and cosmetic outcome in patients treated with interstitial brachytherapy to the tumor bed as the sole radiation modality after breast conserving surgery. MATERIALS AND METHODS: From 11/2000 to 11/2004, 240 women with early stage breast cancer participated in a protocol of tumor bed irradiation alone using pulsed dose rate (PDR) or high dose rate (HDR) interstitial multi-catheter implants (partial breast irradiation). Perioperative morbidity, acute and late toxicity as well as cosmetic outcome were assessed. Of the first 51 patients treated in this multicenter trial, we present interim findings after a median follow-up of 36 months. RESULTS: Perioperative Morbidity: Bacterial infection of the implant: 2 % (1/51). Acute toxicity: radiodermatitis Grade 1: 4 % (2/51). Late toxicity: breast pain Grade 1: 8 % (4/51), Grade 2: 2 % (1/51); dyspigmentation Grade 1: 8 % (4/51); fibrosis Grade 1: 4 % (2/51), Grade 2: 8 % (4/51); telangiectasia Grade 1: 10 % (5/51), Grade 2: 4 % (2/51). Cosmetic results: Excellent and good in 94 % (48/51) of the patients. CONCLUSION: This analysis indicates that accelerated partial breast irradiation with 192-iridium interstitial multicatheter PDR-/HDR-implants (partial breast irradiation) is feasible with low perioperative morbidity, low acute and mild late toxicity at a median follow-up of 36 months. The cosmetic result is not significantly affected.

High-dose intravascular beta-radiation after de novo stent implantation induces coronary artery spasm.

BACKGROUND: Intracoronary brachytherapy is effective in preventing restenosis after coronary interventions. However, in vitro and animal studies have shown that irradiation produces immediate and sustained endothelial dysfunction. This study assesses the clinical relevance of impaired vasomotoric function induced by brachytherapy. METHODS AND RESULTS: We analyzed the occurrence of postradiation coronary artery spasms in 1 animal study and 2 clinical trials investigating the effects of high-dose intracoronary beta-radiation after de novo coronary artery stenting. Irradiated segments (IRSs) proximal and distal to the stent were studied by quantitative coronary angiography after stenting, after radiation, and at the end of the procedure. There was an 67% overall incidence of coronary artery spasm in the IRSs immediately after beta-radiation compared with 9% after sham treatment (P<0.001). Whereas in most cases this phenomenon was only minor or moderate, in 12 cases, 4 (22%) animals and 8 (28%) patients, severe coronary spasm (>90% diameter stenosis) with significant ECG-changes or hemodynamic instability was observed. Relief of spasms was protracted (mean time until complete relief of spasm 423+/-122 seconds) and required repetitive intracoronary administration of nitroglycerin (mean dose: 1.2+/-0.6 mg). CONCLUSIONS: Vasoconstriction is a frequent reaction of coronary arteries after high-dose intracoronary beta-radiation, necessitating repetitive administration of vasodilators.

Alteration of radiation-induced hematotoxicity by amifostine.

PURPOSE: To investigate whether amifostine can reduce radiation hematotoxicity. PATIENTS AND METHODS: Seventy-three patients undergoing radiotherapy for squamous cell carcinoma of the head and neck at the university clinics of Freiburg, Heidelberg, and Erlangen were evaluated. All received 60 Gy (50-70 Gy) at 5 x 2 Gy fractions per week employing standard techniques. Thirty-five were randomized to receive 200 mg/m(2) amifostine i.v. 30 min before radiation; 38 served as control patients. Blood counts (total n = 501) were determined before, during, and while completing radiotherapy. Changes of leukocyte, platelet, and hemoglobin levels were determined and compared using the t test. RESULTS: The blood hemoglobin level and the platelet count were not affected by irradiation, for either the amifostine-treated or control patients. Similarly, the leukocyte counts of amifostine-treated patients did not change during irradiation. However, control patients experienced a decrease in leukocyte count from 8.1 x 10(3)/mm(3) to 5.8 x 10(3)/mm(3) (difference: 2.3 x 10(3)/mm(3)). This seems to be line specific: Whereas amifostine does not affect lymphocyte count, a radiation-induced decrease of neutrophil granulocytes seems to be prevented. CONCLUSION: Amifostine protects from radiation hematotoxicity, particularly affecting the granulocytopoiesis. These data confirm results from our former study.