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Macias V.A.,University of Salamanca | Blanco M.L.,University of Salamanca | Barrera I.,University of Salamanca | Garcia R.,CyberKnife Unit
Frontiers in Oncology | Year: 2014

Endpoint: To assess early urinary (GU) and rectal (GI) toxicities after helical tomotherapy Stereotactic body radiation therapy (SBRT), and to determine their predictive factors. Methods: Since May 2012, 45 prostate cancer patients were treated with eight fractions of 5.48 (low risk, 29%) or 5.65 Gy (intermediate-high risk, 71%) on alternative days over 2.5 weeks. The exclusion criteria were Gleason score 9-10, PSA >40 ng/mL, cT3b-4, IPSS =20, and history of acute urinary retention. During the follow-up, a set of potential prognostic factors was correlated with urinary or rectal toxicity. Results: The median follow-up was 13.8 months (2-25 months). There were no grade =3 toxicities. Acute grade 2 GU complications were found in a 22.7% of men, but in 2.3% of patients at 1 month, 0% at 6 months, and 0% at 12 months. The correspondent figures for grade 2 GI toxicities were 20.4% (acute), 2.3% (1 month), 3.6% (6 months), and 5% (12 months). Acute GI toxicity was significantly correlated with the rectal volume (>15 cm3) receiving 28 Gy, only when expressed as absolute volume. The age (>72 years old) was a predictor of GI toxicity after 1 month of treatment. No correlation was found, however, between urinary toxicity and the other analyzed variables. IPSS increased significantly at the time of the last fraction and within the first month, returning to the baseline at sixth month. Urinary-related quality of life (IPSS question 8 score), it was not significantly worsen during radiotherapy returning to the baseline levels 1 month after the treatment. At 12 months follow-up patient's perception of their urinary function improved significantly in comparison with the baseline. Conclusion: Our scheme of eight fractions on alternative days delivered using helical tomotherapy is well tolerated. We recommend using actual volume instead of percentual volume in the treatment planning, and not to exceed 15 cm3 of rectal volume receiving ≥25 Gy in order to diminish acute GI toxicity. © 2014 Macias, Blanco, Barrera and Garcia. Source

Canazza A.,Laboratory of Clinical Investigation | De Grazia U.,Laboratory of Clinical Investigation | Fumagalli L.,Radiotherapy Unit | Brait L.,CyberKnife Unit | And 5 more authors.
Neurological Sciences | Year: 2011

Radiosurgery is used increasingly upon recurrence of high-grade gliomas to deliver a high dose of focused radiation to a defined target. The purpose of our study was to compare intermittent irradiation (IIR) by using a CyberKnife (CK) with continuous irradiation (CIR) by using a conventional linear accelerator (LINAC). A significant decrease in surviving fraction was observed after IIR irradiation compared with after CIR at a dose of 8 Gy. Three hours after irradiation, most of the DNA damage was repaired in U87. Slightly higher basal levels of Ku70/80 mRNA were found in U87 compared with A172, while radiation treatment induced only minor regulation of Ku70/ 80 and Rad51 transcription in either cell lines. IIR treatment using CK significantly decreased the survival in U87 and A172 compared with CIR. Although the two cell lines differed in DNA repair capability, the role of Ku70/80 and Rad51 in the cell line radiosensitivity seemed marginal. © 2011 Springer-Verlag. Source

Canazza A.,Laboratory of Clinical Investigation | Calatozzolo C.,Laboratory of Clinical Investigation | Calatozzolo C.,Neuropathology Unit | Fumagalli L.,Radiotherapy Unit | And 6 more authors.
Cancer Biology and Therapy | Year: 2011

A human glioblastoma multiforme cell line (U87) and its derived-spheroids were irradiated either using a conventional irradiation (CIR) or a CK-like irradiation (IIR) in which the 8 Gy was delivered intermittently over a period of 40 min. The ability of glioma cells to migrate into a matrigel matrix was evaluated on days 1-8 from irradiation. Irradiation with CKdriven IIR significantly increased the invasion potential of U87 cells in a matrigel-based assay. In contrast to CIR, IIR was associated with increased levels of TGFβ at four days (real-time PCR), β1-integrin at 4-5 d (real-time PCR and protein gel blot) and no elevation in phosphorylated AKT at days 4 and 5 (protein gel blot). Our data suggests that glioma cell invasion as well as elevations of TGFβ and β1-integrin are associated with IIR and not CIR. © 2011 Landes Bioscience. Source

Vavassori A.,Oncology and Radiotherapy Institute | Jereczek-Fossa B.A.,Oncology and Radiotherapy Institute | Jereczek-Fossa B.A.,University of Milan | Beltramo G.,CyberKnife Unit | And 9 more authors.
Tumori | Year: 2010

Aims and background. Technological advances in treatment planning and execution are providing new potential opportunities in the treatment of recurrent prostate cancer. This studywas conducted to evaluate the feasibility and safety of reirradiationwith image-guided radiosurgery using CyberKnife, a robotic arm-driven compact linear accelerator, for intraprostatic recurrence after external beam radiotherapy (EBRT). Methods. Between September 2007 and May 2008, 6 patients diagnosed with locally recurrent prostate cancer after EBRT were treated using the CyberKnife system. The total reirradiation dose was 30 Gy in five fractions. Prior to radiosurgery four patients were treated with androgen-deprivation therapy. Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria and the Houston-Phoenix definition (PSA nadir + 2 ng/mL) were used for toxicity and biochemical failure evaluation, respectively. Results. After a median follow-up of 11.2 months (range, 9.6-18.6 months), all patients are alive with no evidence of severe urinary or rectal acute morbidity. Local control cannot be exactly determined due to the short follow-up and the bias of the use of androgen ablation. Four patients had biochemical failure, three of them with clinical failure evidence (lymph node, bone and lung metastasis, respectively): none of these patients had clinical evidence of tumor persistence in the prostate. Conclusions. Salvage radiosurgery with CyberKnife after irradiation is feasible with low urinary and rectal morbidity. A longer follow-up and a larger number of patients are necessary to evaluate its effectiveness and optimal patient selection criteria. Free full text available at www.tumorionline.it. Source

Floriano A.,CyberKnife Unit | Santa-Olalla I.,CyberKnife Unit | Sanchez-Reyes A.,CyberKnife Unit
Reports of Practical Oncology and Radiotherapy | Year: 2013

Aim: To analyze intrafraction movement in patients undergoing frameless robotic radiosurgery and evaluate the influence of image acquisition frequency on global accuracy. Background: Stereotactic radiosurgery requires high spatial accuracy in dose delivery. In conventional radiosurgery, a rigid frame is used to guarantee a correct target alignment and no subsequent movement. Frameless radiosurgery with thermoplastic mask for immobilization cannot completely eliminate intrafraction patient movement. In such cases, it is necessary to evaluate its influence on global treatment accuracy. Materials and methods: We analyzed the intrafraction motion of the first 15 patients undergoing intracranial radiosurgery (39 fractions) with the CyberKnife VSI system at our institution. Patient position was measured at a 15-90-s interval and was used to estimate intrafraction patient movement. Results: With our acquisition image protocol and immobilization device, the 99% displacement error was lower than 0.85. mm. The systematic movement components were lower than 0.05. mm and the random component was lower than 0.3. mm in the 3 translational axes. Clear linear time dependence was found in the random component. Conclusions: Selection of the X-ray image acquisition time is necessary to meet the accuracy required for radiosurgery procedures with the CyberKnife VSI system. We verified that our image acquisition protocol met the 1-mm criterion. © 2013 Greater Poland Cancer Centre. Source

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