Olivier Riou

Mobile Technology and Social Media in the Clinical Practice of Young Radiation Oncologists: Results of a Comprehensive Nationwide Cross-sectional Study

PURPOSEnSocial media and mobile technology are transforming the way in which young physicians are learning and practicing medicine. The true impact of such technologies has yet to be evaluated.nnnMETHODS AND MATERIALSnWe performed a nationwide cross-sectional survey to better assess how young radiation oncologists used these technologies. An online survey was sent out between April 24, 2013, and June 1, 2013. All residents attending the 2013 radiation oncology French summer course were invited to complete the survey. Logistic regressions were performed to assess predictors of use of these tools in the hospital on various clinical endpoints.nnnRESULTSnIn all, 131 of 140 (93.6%) French young radiation oncologists answered the survey. Of these individuals, 93% owned a smartphone and 32.8% owned a tablet. The majority (78.6%) of the residents owning a smartphone used it to work in their department. A total of 33.5% had more than 5 medical applications installed. Only 60.3% of the residents verified the validity of the apps that they used. In all, 82.9% of the residents had a social network account.nnnCONCLUSIONSnMost of the residents in radiation oncology use their smartphone to work in their department for a wide variety of tasks. However, the residents do not consistently check the validity of the apps that they use. Residents also use social networks, with only a limited impact on their relationship with their patients. Overall, this study highlights the irruption and the risks of new technologies in the clinical practice and raises the question of a possible regulation of their use in the hospital.

Integrating respiratory-gated PET-based target volume delineation in liver SBRT planning, a pilot study

BackgroundTo assess the feasibility and benefit of integrating four-dimensional (4D) Positron Emission Tomography (PET) – computed tomography (CT) for liver stereotactic body radiation therapy (SBRT) planning.Methods8 patients with 14 metastases were accrued in the study. They all underwent a non-gated PET and a 4D PET centered on the liver. The same CT scan was used for attenuation correction, registration, and considered the planning CT for SBRT planning. Six PET phases were reconstructed for each 4D PET. By applying an individualized threshold to the 4D PET, a Biological Internal Target Volume (BITV) was generated for each lesion. A gated Planning Target Volume (PTVg) was created by adding 3xa0mm to account for set-up margins. This volume was compared to a manual Planning Target Volume (PTV) delineated with the help of a semi-automatic Biological Target Volume (BTV) obtained from the non-gated exam. A 5xa0mm radial and a 10xa0mm craniocaudal margins were applied to account for tumor motion and set-up margins to create the PTV.ResultsOne undiagnosed liver metastasis was discovered thanks to the 4D PET. The semi-automatic BTV were significantly smaller than the BITV (pu2009=u20090.0031). However, after applying adapted margins, 4D PET allowed a statistically significant decrease in the PTVg as compared to the PTV (pu2009=u20090.0052).ConclusionsIn comparison to non-gated PET, 4D PET may better define the respiratory movements of liver targets and improve SBRT planning for liver metastases. Furthermore, non respiratory-gated PET exams can both misdiagnose liver metastases and underestimate the real internal target volumes.

Simultaneous integrated boost plan comparison of volumetric-modulated arc therapy and sliding window intensity-modulated radiotherapy for whole pelvis irradiation of locally advanced prostate cancer

Concurrent radiotherapy to the pelvis plus a prostate boost with long‐term androgen deprivation is a standard of care for locally advanced prostate cancer. IMRT has the ability to deliver highly conformal dose to the target while lowering irradiation of critical organs around the prostate. Volumetric‐modulated arc therapy is able to reduce treatment time, but its impact on organ sparing is still controversial when compared to static gantry IMRT. We compared the two techniques in simultaneous integrated boost plans. Ten patients with locally advanced prostate cancer were included. The planning target volume (PTV) 1 was defined as the pelvic lymph nodes, the prostate, and the seminal vesicles plus setup margins. The PTV2 consisted of the prostate with setup margins. The prescribed doses to PTV1 and PTV2 were 54 Gy in 37 fractions and 74 Gy in 37 fractions, respectively. We compared simultaneous integrated boost plans by means of either a seven coplanar static split fields IMRT, or a one‐arc (RA1) and a two‐arc (RA2) RapidArc planning. All three techniques allowed acceptable homogeneity and PTV coverage. Static IMRT enabled a better homogeneity for PTV2 than RapidArc techniques. Sliding window IMRT and VMAT permitted to maintain doses to OAR within acceptable levels with a low risk of side effects for each organ. VMAT plans resulted in a clinically and statistically significant reduction in doses to bladder (mean dose IMRT: 50.1±4.6Gy vs. mean dose RA2: 47.1±3.9Gy,p=0.037), rectum (mean dose IMRT: 44±4.5 vs. mean dose RA2:41.6±5.5Gy,p=0.006), and small bowel (V30IMRT:76.47±14.91% vs. V30RA2:47.49±16.91%,p=0.002). Doses to femoral heads were higher with VMAT but within accepted constraints. Our findings suggest that simultaneous integrated boost plans using VMAT and sliding window IMRT allow good OAR sparing while maintaining PTV coverage within acceptable levels. PACS number: 87.53.Jw

Eight years of IMRT quality assurance with ionization chambers and film dosimetry: experience of the montpellier comprehensive cancer center

BackgroundTo present the results of quality assurance (QA) in IMRT of film dosimetry and ionization chambers measurements with an eight year follow-up.MethodsAll treatment plans were validated under the linear accelerator by absolute and relative measures obtained with ionization chambers (IC) and with XomatV and EDR2 films (Kodak).ResultsThe average difference between IC measured and computed dose at isocenter with the gantry angle of 0° was 0.07 ± 1.22% (average ± 1 SD) for 2316 prostate, 1.33 ± 3.22% for 808 head and neck (h&n), and 0.37 ± 0.62% for 108 measurements of prostate bed fields. Pelvic treatment showed differences of 0.49 ± 1.86% in 26 fields for prostate cases and 2.07 ± 2.83% in 109 fields of anal canal.Composite measurement at isocenter for each patient showed an average difference with computed dose of 0.05 ± 0.87% for 386 prostate, 1.49 ± 1.86% for 158 h&n, 0.37 ± 0.34% for 23 prostate bed, 0.80 ± 0.28% for 4 pelvis, and 2.31 ± 0.56% for 17 anal canal cases. On the first 250 h&n analyzed by film in absolute dose, the average of the points crossing a gamma index 3% and 3 mm was 93%. This value reached 99% for the prostate fields.ConclusionMore than 3500 beams were found to be within the limits defined as validated for treatment between 2001 and 2008.

Role of the Radiotherapy Boost on Local Control in Ductal Carcinoma In Situ

Ductal carcinoma in situ of the breast is associated with low mortality rates, but local relapse is a matter of concern in this disease. Risk factors for local relapse include young age, close or positive margins, and tumor necrosis. Whole breast irradiation following breast-conserving surgery for ductal carcinoma in situ significantly reduces the risk of local relapse as compared to breast-conserving surgery alone. Studies point to similar outcomes between breast-conserving surgery plus radiotherapy and mastectomy, in the absence of extensive disease. A complementary boost to the surgical bed improves outcomes for patients with invasive breast cancer. However, the effect of this strategy has never been prospectively reported for ductal carcinoma in situ. Two randomized controlled trials assessing this issue are ongoing. This paper represents an update on available literature about radiotherapy for DCIS with a special focus on the role of a radiotherapy boost to the tumor bed.

Bilateral kidney preservation by volumetric-modulated arc therapy (RapidArc) compared to conventional radiation therapy (3D-CRT) in pancreatic and bile duct malignancies

BackgroundTo compare volumetric-modulated arc therapy plans with conventional radiation therapy (3D-CRT) plans in pancreatic and bile duct cancers, especially for bilateral kidney preservation.MethodsA dosimetric analysis was performed in 21 patients who had undergone radiotherapy for pancreatic or bile duct carcinoma at our institution. We compared 4-field 3D-CRT and 2 arcs RapidArc (RA) plans. The treatment plan was designed to deliver a dose of 50.4 Gy to the planning target volume (PTV) based on the gross disease in a 1.8 Gy daily fraction, 5 days a week. Planning objectives were 95% of the PTV receiving 95% of the prescribed dose and no more than 2% of the PTV receiving more than 107%. Dose-volume histograms (DVH) for the target volume and the organs at risk (right and left kidneys, bowel tract, liver and healthy tissue) were compared. Monitor units and delivery treatment time were also reported.ResultsAll plans achieved objectives, with 95% of the PTV receiving ≥ 95% of the dose (D95% for 3D-CRT = 48.9 Gy and for RA = 48.6 Gy). RapidArc was shown to be superior to 3D-CRT in terms of organ at risk sparing except for contralateral kidney: for bowel tract, the mean dose was reduced by RA compared to 3D-CRT (16.7 vs 20.8 Gy, p = 0.0001). Similar result was observed for homolateral kidney (mean dose of 4.7 Gy for RA vs 12.6 Gy for 3D-CRT, p < 0.0001), but 3D-CRT significantly reduced controlateral kidney dose with a mean dose of 1.8 Gy vs 3.9 Gy, p < 0.0007. Compared to 3D-CRT, mean MUs for each fraction was significantly increased with RapidArc: 207 vs 589, (p < 0.0001) but the treatment time was not significantly different (2 and 2.66 minutes, p = ns).ConclusionRapidArc allows significant dose reduction, in particular for homolateral kidney and bowel, while maintaining target coverage. This would have a promising impact on reducing toxicities.

Helical tomotherapy and volumetric modulated arc therapy: New therapeutic arms in the breast cancer radiotherapy

AIMnTo analyse clinical and dosimetric results of helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT) in complex adjuvant breast and nodes irradiation.nnnMETHODSnSeventy-three patients were included (31 HT and 42 VMAT). Dose were 63.8 Gy (HT) and 63.2 Gy (VMAT) in the tumour bed, 52.2 Gy in the breast, 50.4 Gy in supraclavicular nodes (SCN) and internal mammary chain (IMC) with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions. Margins to particle tracking velocimetry were greater in the VMAT cohort (7 mm vs 5 mm).nnnRESULTSnFor the HT cohort, the coverage of clinical target volumes was as follows: Tumour bed: 99.4% ± 2.4%; breast: 98.4% ± 4.3%; SCN: 99.5% ± 1.2%; IMC: 96.5% ± 13.9%. For the VMAT cohort, the coverage was as follows: Tumour bed: 99.7% ± 0.5%, breast: 99.3% ± 0.7%; SCN: 99.6% ± 1.4%; IMC: 99.3% ± 3%. For ipsilateral lung, Dmean and V20 were 13.6 ± 1.2 Gy, 21.1% ± 5% (HT) and 13.6 ± 1.4 Gy, 20.1% ± 3.2% (VMAT). Dmean and V30 of the heart were 7.4 ± 1.4 Gy, 1% ± 1% (HT) and 10.3 ± 4.2 Gy, 2.5% ± 3.9% (VMAT). For controlateral breast Dmean was 3.6 ± 0.2 Gy (HT) and 4.6 ± 0.9 Gy (VMAT). Acute skin toxicity grade 3 was 5% in the two cohorts.nnnCONCLUSIONnHT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance. A longer follow-up is needed to assess the impact of low doses to healthy tissues.

Radiothérapie conformationnelle avec modulation d’intensité dans les cancers du sein : intérêt, limitations, modalités techniques

Intensity modulated radiotherapy (IMRT) is a technique allowing dose escalation and normal tissue sparing for various cancer types. For breast cancer, the main goals when using IMRT were to improve dose homogeneity within the breast and to enhance coverage of complex target volumes. Nonetheless, better heart and lung protections are achievable with IMRT as compared to standard irradiation for difficult cases. Three prospective randomized controlled trials of IMRT versus standard treatment showed that a better breast homogeneity can translate into better overall cosmetic results. Dosimetric and clinical studies seem to indicate a benefit of IMRT for lymph nodes irradiation, bilateral treatment, left breast and chest wall radiotherapy, or accelerated partial breast irradiation. The multiple technical IMRT solutions available tend to indicate a widespread use for breast irradiation. Nevertheless, indications for breast IMRT should be personalized and selected according to the expected benefit for each individual.

Implementing intensity modulated radiotherapy to the prostate bed: Dosimetric study and early clinical results

Salvage intensity modulated radiotherapy (IMRT) to the prostate bed has hardly been studied so far. We present here a feasibility study and early clinical results for 10 patients. These patients were selected on the basis of having either a biochemical relapse or high risk histology after prostatectomy. They were treated using sliding-window IMRT to 68 Gy in 34 fractions. Three-dimensional conformal radiotherapy (3D-CRT) plans were generated using the same planning computed tomography data set. Dose coverage of planning target volumes (PTVs) and of organs-at-risk (OAR, namely: rectum, bladder, and femoral heads) were compared. Acute toxicity and chronic toxicity were measured using the Common Toxicity Criteria for Adverse Events version 3.0 scale. IMRT significantly reduces the dose above the prescription dose given to the PTV1 (mean dose: IMRT 67.2 Gy vs 3D-CRT 67.7 Gy (p = 0.0137)), without altering dose coverage for PTV2 (mean dose: IMRT 68.1 Gy vs 3D-CRT 68.0 Gy (p = 0.3750)). Doses to OAR were lower with IMRT and differences were statistically significant (mean dose: IMRT 51.4 Gy vs 3D-CRT 56.6 Gy for rectum (p = 0.002), IMRT 45.1 Gy vs 3D-CRT 53.1 Gy for bladder (p = 0.002), and IMRT 26.1 Gy vs 3D-CRT 28.4 Gy for femoral heads (p = 0.0059)). There was no acute or chronic genitourinary or gastrointestinal toxicity >1 with a median follow-up of 38 months. IMRT to the prostatic fossa is feasible and reduces dose to OAR, with consequential limited toxicity.

Delegation of medical tasks in French radiation oncology departments: Current situation and impact on residents’ training

OBJECTIVESnA national survey was conducted among the radiation oncology residents about their clinical activities and responsibilities. The aim was to evaluate the clinical workload and to assess how medical tasks are delegated and supervised.nnnMATERIALS AND METHODSnA first questionnaire was administered to radiation oncology residents during a national course. A second questionnaire was mailed to 59 heads of departments.nnnRESULTSnThe response rate was 62% for radiation oncology residents (99 questionnaires) and 51% for heads of department (30). Eighteen heads of department (64%) declared having written specifications describing the residents clinical tasks and roles, while only 31 radiation oncology residents (34%) knew about such a document (P=0.009). A majority of residents were satisfied with the amount of medical tasks that were delegated to them. Older residents complained about insufficient exposure to new patients consultation, treatment planning and portal images validation. The variations observed between departments may induce heterogeneous trainings and should be addressed specifically.nnnCONCLUSIONnNational specifications are necessary to reduce heterogeneities in training, and to insure that the residents training covers all the professional skills required to practice radiation oncology. A frame endorsed by academic and professional societies would also clarify the responsibilities of both residents and seniors.