Whole breast radiotherapy in prone and supine position: is there a place for multi-beam IMRT?

Background: Early stage breast cancer patients are long-term survivors and finding techniques that may lower acute and late radiotherapy-induced toxicity is crucial. We compared dosimetry of wedged tangential fields (W-TF), tangential field intensity-modulated radiotherapy (TF-IMRT) and multi-beam IMRT (MB-IMRT) in prone and supine positions for whole-breast irradiation (WBI). Methods: MB-IMRT, TF-IMRT and W-TF treatment plans in prone and supine positions were generated for 18 unselected breast cancer patients. The median prescription dose to the optimized planning target volume (PTVoptim) was 50 Gy in 25 fractions. Dose-volume parameters and indices of conformity were calculated for the PTVoptim and organs-at-risk. Results: Prone MB-IMRT achieved (p= 600 cc heart dose was consistently lower in prone position; while for patients with smaller breasts heart dose metrics were comparable or worse compared to supine MB-IMRT. Doses to the contralateral breast were similar regardless of position or technique. Dosimetry of prone MB-IMRT and prone TF-IMRT differed slightly. Conclusions: MB-IMRT is the treatment of choice in supine position. Prone IMRT is superior to any supine treatment for right-sided breast cancer patients and left-sided breast cancer patients with larger breasts by obtaining better conformity indices, target dose distribution and sparing of the organs-at-risk. The influence of treatment techniques in prone position is less pronounced; moreover dosimetric differences between TF-IMRT and MB-IMRT are rather small

Dose-intensified stereotactic body radiotherapy for painful vertebral metastases: A randomized phase 3 trial.

BACKGROUND The purpose of this randomised study was to determine whether dose-intensified stereotactic body radiotherapy (SBRT) for painful vertebral metastases results in increased rates of pain improvement compared with conventional external beam radiotherapy (cEBRT) (control) 6 months after treatment. METHODS This randomized, controlled phase 3 trial was conducted between November 2016 and January 2023, when it was stopped early. Patients were eligible if they were aged 18 years or older; had one or two painful, stable, or potentially unstable vertebral metastases; and had a life expectancy of 1 year or longer according to the investigator's estimates. Patients received 48.5 grays (Gy) in 10 fractions (with epidural involvement) or 40 Gy in five fractions (without epidural involvement) in the SBRT group and 30 Gy in 10 fractions or 20 Gy in five fractions in the cEBRT group, respectively. The primary end point was an improvement in the pain score at the treated site by at least 2 points (on a visual analog scale from 0 to 10 points) at 6-month follow-up. Data were analyzed on an intention-to-treat and per-protocol basis. RESULTS Of 214 patients who were screened for eligibility, 63 were randomized 1:1 between SBRT (33 patients with 36 metastases) and cEBRT (30 patients with 31 metastases). The median age of all patients was 66 years, and 40 patients were men (63.5%). In the intention-to-treat analysis, the 6-month proportion of patients who had metastases with pain reduction by 2 or more points was significantly higher in the SBRT group versus the control group (69.4% vs. 41.9%, respectively; two-sided p = .02). Changes in opioid medication intake relative to baseline were nonsignificant between the groups. No differences were observed in vertebral compression fracture or adverse event rates between the groups. CONCLUSIONS Dose-intensified SBRT improved pain score more effectively than cEBRT at 6 months

Role of Mobility Strategy in moderating the effect Of ERP performance to operational performance: (Study in Indonesian palm oil plantation industries)

Introduction: Inter-observer variability (IOV) in target volume delineation is a well-documented source of geometric uncertainty in radiotherapy. Such variability has not yet been explored in the context of adaptive re-delineation based on imaging data acquired during treatment. We compared IOV in the pre- and mid-treatment setting using expert primary gross tumour volume (GTV) and clinical target volume (CTV) delineations in locoregionally advanced head-and-neck squamous cell carcinoma (HNSCC) and (non-)small cell lung cancer [(N)SCLC]. Material and methods: Five and six observers participated in the HNSCC and (N)SCLC arm, respectively, and provided delineations for five cases each. Imaging data consisted of CT studies partly complemented by FDG-PET and was provided in two separate phases for pre- and mid-treatment. Global delineation compatibility was assessed with a volume overlap metric (the Generalised Conformity Index), while local extremes of IOV were identified through the standard deviation of surface distances from observer delineations to a median consensus delineation. Details of delineation procedures, in particular, GTV to CTV expansion and adaptation strategies, were collected through a questionnaire. Results: Volume overlap analysis revealed a worsening of IOV in all but one case per disease site, which failed to reach significance in this small sample (p-value range .063-.125). Changes in agreement were propagated from GTV to CTV delineations, but correlation could not be formally demonstrated. Surface distance based analysis identified longitudinal target extent as a pervasive source of disagreement for HNSCC. High variability in (N)SCLC was often associated with tumours abutting consolidated lung tissue or potentially invading the mediastinum. Adaptation practices were variable between observers with fewer than half stating that they consistently adapted pre-treatment delineations during treatment. Conclusion: IOV in target volume delineation increases during treatment, where a disparity in institutional adaptation practices adds to the conventional causes of IOV. Consensus guidelines are urgently needed

Does ionizing radiation stimulate cancer invasion and metastasis?

Radiotherapy (RT) is a form of local treatment used mainly for malignant tumors. Such tumors originate from mutated stein cells, During their development they do attract a variety of host cells, coined tumor-associated host cells. Malignant tumors are characterized by uncontrolled growth,. invasion and metastasis'. the latter being the major cause of death of patients, even when their primary tumor is under control. RT inhibits growth. There are, however. clinical data suggesting that, under some circumstances, it may stimulate metastasis. DNA is a target of ionizing radiation (IR), though not the only one. IR produces cascades of growth factors and chemokines; it activates molecules initiating multiple signaling pathways that modulate several cellular Junctions. We consider cancer as a network of ecosystems, including at least the founder primary tumor, the site of metastasis and the hone marrow. As these ecosystems are in continuous communication, it is not surprising that R T of the primary tumor influences metastasis. Indeed, experiments with cells in culture and with animal tumors have shown that IR stimulates invasion and metastasis and activates pro-invasive and prometastatic cellular activities through upregulation of key molecules. At certain doses and within certain time frames, IR enhances the activities of the tumor-associated host cells that support invasion and metastasis, namely: endothelial cells building new vessels; leucocytes and macrophages causing inflammation; myofibroblasts initiating desmoplasia; osteoblasts and osteoclasts establishing hone metastasis; nerve cells producing efferent growth- and invasion-promoting molecules. Techniques such as spatially fractioned radiotherapy and hadron therapy may have different effects on metastasis. Taking into consideration the dose- and time-dependency of the IR-induced tumor-associated host cell reactions, these techniques, as well as the conventional ones, should he combined with repetitive biological imaging, reevaluation of planning and eventual replanning during the course of the treatment

Modern treatment for nasopharyngeal carcinoma : current status and prospects

Purpose of review : In this article, we focus on the role of Epstein-Barr virus in the management of nasopharyngeal cancer, intensity-modulated radiotherapy, adjuvant and neoadjuvant chemotherapy, and targeted therapy. Recent findings : Epstein-Barr virus DNA clearance has recently been studied for prediction of tumor response and survival. Patients with a short t1/2 of plasma Epstein-Barr virus DNA clearance had significantly higher responses and survival than those with long t1/2. Intensity-modulated radiotherapy, delivering higher doses to the tumor, results in improved local control and overall survival at lower treatment-induced toxicity. Recent reports show that re-planning during the course of radiotherapy could influence outcome and toxicity. The use of newer platinum compounds and combinations with taxanes in adjuvant and neoadjuvant setting have been investigated in phase II trials. They demonstrate acceptable toxicity profiles and promising treatment outcomes. However, antiepidermal growth factor receptor and antivascular endothelial growth factor receptor agents do not show important responses in metastatic disease and when combined with radiotherapy, toxicity is of concern. Summary : Epstein-Barr virus DNA has a potential as a risk stratification marker. Intensity-modulated radiotherapy is standard treatment and adaptive radiotherapy with re-planning has to be considered. Uncertainties on adjuvant/neoadjuvant chemotherapy should be addressed in well designed randomized trials. Currently, the role of targeted agents is not well defined