Stereotactic body radiation therapy for liver tumours using flattening filter free beam: dosimetric and technical considerations

Purpose: To report the initial institute experience in terms of dosimetric and technical aspects in stereotactic body radiation therapy (SBRT) delivered using flattening filter free (FFF) beam in patients with liver lesions.Methods and Materials: From October 2010 to September 2011, 55 consecutive patients with 73 primary or metastatic hepatic lesions were treated with SBRT on TrueBeam using FFF beam and RapidArc technique. Clinical target volume (CTV) was defined on multi-phase CT scans, PET/CT, MRI, and 4D-CT. Dose prescription was 75 Gy in 3 fractions to planning target volume (PTV). Constraints for organs at risk were: 700 cc of liver free from the 15 Gy isodose, D max < 21 Gy for stomach and duodenum, D max < 30 Gy for heart, D 0.1 cc < 18 Gy for spinal cord, V 15 Gy < 35% for kidneys. The dose was downscaled in cases of not full achievement of dose constraints. Daily cone beam CT (CBCT) was performed.Results: Forty-three patients with a single lesion, nine with two lesions and three with three lesions were treated with this protocol. Target and organs at risk objectives were met for all patients. Mean delivery time was 2.8 ± 1.0 min. Pre-treatment plan verification resulted in a Gamma Agreement Index of 98.6 ± 0.8%. Mean on-line co-registration shift of the daily CBCT to the simulation CT were: -0.08, 0.05 and -0.02 cm with standard deviations of 0.33, 0.39 and 0.55 cm in, vertical, longitudinal and lateral directions respectively.Conclusions: SBRT for liver targets delivered by means of FFF resulted to be feasible with short beam on time. © 2012 Mancosu et al; licensee BioMed Central Ltd

Compatibility between entomopathogenic fungi and biorational insecticides in toxicity against Ronderosia bergi under laboratory conditions

Our aim was to evaluate the efficacy of combinations between two biorational insecticides (luphenuron, methoxyfenozide), a new synthetic chemical pesticide (rynaxypyr), and three entomopathogenic fungi strains (Beauveria bassianaLPSc 1067, LPSc1082), and Metarhizium anisopliae (LPSc 907) in the biocontrol of the pest grasshopper Ronderosia bergi (Stål) under laboratory conditions. The insecticides were tested at three concentrations: the average concentration recommended for application in the field (100%) and 50% and finally 25% of that level. The fungal strains used were adjusted to 1×108, 1×106, and 1×104conidia ml-1. The combinations of those insecticides with B. bassiana (LPSc 1067, LPSc 1082) and M. anisopliae (LPSc 907) caused higher mortality to R. bergi nymphs than any of the individual agents used alone. The three insecticides tested did not affect the isolates of the two species of entomopathogenic fungi employed. In conclusion, the use of these biorational insecticides in an IPM program aimed at control of the grasshopper R. bergicould be of value

Characterisation and classification of oligometastatic disease : a European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer consensus recommendation

Oligometastatic disease has been proposed as an intermediate state between localised and systemically metastasised disease. In the absence of randomised phase 3 trials, early clinical studies show improved survival when radical local therapy is added to standard systemic therapy for oligometastatic disease. However, since no biomarker for the identification of patients with true oligometastatic disease is clinically available, the diagnosis of oligometastatic disease is based solely on imaging findings. A small number of metastases on imaging could represent different clinical scenarios, which are associated with different prognoses and might require different treatment strategies. 20 international experts including 19 members of the European Society for Radiotherapy and Oncology and European Organisation for Research and Treatment of Cancer OligoCare project developed a comprehensive system for characterisation and classification of oligometastatic disease. We first did a systematic review of the literature to identify inclusion and exclusion criteria of prospective interventional oligometastatic disease clinical trials. Next, we used a Delphi consensus process to select a total of 17 oligometastatic disease characterisation factors that should be assessed in all patients treated with radical local therapy for oligometastatic disease, both within and outside of clinical trials. Using a second round of the Delphi method, we established a decision tree for oligometastatic disease classification together with a nomenclature. We agreed oligometastatic disease as the overall umbrella term. A history of polymetastatic disease before diagnosis of oligometastatic disease was used as the criterion to differentiate between induced oligometastatic disease (previous history of polymetastatic disease) and genuine oligometastatic disease (no history of polymetastatic disease). We further subclassified genuine oligometastatic disease into repeat oligometastatic disease (previous history of oligometastatic disease) and de-novo oligometastatic disease (first time diagnosis of oligometastatic disease). In de-novo oligometastatic disease, we differentiated between synchronous and metachronous oligometastatic disease. We did a final subclassification into oligorecurrence, oligoprogression, and oligopersistence, considering whether oligometastatic disease is diagnosed during a treatment-free interval or during active systemic therapy and whether or not an oligometastatic lesion is progressing on current imaging. This oligometastatic disease classification and nomenclature needs to be prospectively evaluated by the OligoCare study

Stereotactic radiotherapy for ultra-central lung oligometastases in non-small-cell lung cancer

Background: Stereotactic body radiotherapy (SBRT) in ultra-central (UC) lung tumors, defined in the presence of planning target volume (PTV) overlap or direct tumor abutment to the central bronchial tree or esophagus, may be correlated to a higher incidence of severe adverse events. Outcome and toxicity in oligometastatic (≤3 metastases) non-small-cell lung cancer (NSCLC) patients receiving SBRT for UC tumors were evaluated. Methods: Oligometastatic NSCLC patients treated with SBRT for UC were retrospectively reviewed. Local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS) and overall survival (OS) were calculated. Incidence and grade of toxicity were evaluated. Statistical analysis was performed to assess the impact of clinical and treatment-related variables on outcome and toxicity occurrence. Results: Seventy-two patients were treated to a median biologically effective dose (BED) of 105 (75–132) Gy10 . Two-year LC, DMFS, PFS, and OS were 83%, 46%, 43%, and 49%. BED>75 Gy10 was correlated to superior LC (p = 0.02), PFS (p = 0.036), and OS (p < 0.001). Grade ≥3 toxicity rate was 7%, including one fatal esophagitis. No variables were correlated to DMFS or to occurrence of overall and grade ≥3 toxicity. Conclusions: SBRT using dose-intensive schedules improves outcome in NSCLC patients. Overall toxicity is acceptable, although rare but potentially fatal toxicities may occur