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1.  Optimisation of Radiation Exposure to Gastroenterologists and Patients during Therapeutic ERCP 
This study intended to optimize the radiation doses for gastroenterologists and patients during therapeutic endoscopic retrograde cholangiopancreatography (ERCP) and to compare the doses based on available data obtained by other researchers. A total of 153 patients were studied in two Gastroenterology Departments, (group A, 111; group B, 42). Thermoluminescent dosimeters (TLD) were used to measure the staff and patients entrance surface air kerma (ESAK) at different body sites. The mean ESAK and effective doses per procedure were estimated to be 68.75 mGy and 2.74 mSv, respectively. Staff was exposed to a heterogonous doses. The third examiner (trainee) was exposed to a high dose compared with other examiners because no shield was located to protect him from stray radiation. Patients and examiners doses were lower compared to the lowest values found in previous studies taking into consideration the heterogeneity of patients and equipment. Staff doses during ERCP are within the safety limit in the light of the current practice.
PMCID: PMC3622381  PMID: 23589714
2.  Radiotherapy of early breast cancer in scleroderma patients: our experience with four cases and a short review of the literature 
Connective vascular diseases (CVD), including scleroderma, are reported to represent for some researchers a relative contraindication and for others absolute contraindication for radiotherapy. The purpose of our study is to add four new cases to the existing body of international literature and to determine whether women with pre-existing scleroderma who have been surgically treated for early breast cancer could undergo postsurgical radiotherapy without serious early and late complications.
Patients and methods
From May 1998 to November 2010, we irradiated for early breast cancer four patients suffering from pre-existing scleroderma; after conservative surgery, we performed whole breast postoperative radiotherapy of 50.4 Gy total dose to the whole breast plus a 9 Gy boost to the tumor bed. We reviewed the records of all four patients and evaluated the early and late reactions using acute radiation morbidity scoring criteria (Radiation Therapy Oncology Group [RTOG], American College of Radiology, Philadelphia, PA) and late radiation morbidity scoring scheme (European Organisation for Research and Treatment of Cancer [EORTC], Brussels, Belgium and RTOG).
After a median follow-up of 105 months (range 12–155 months) the early and late toxicity concerning the skin, the subcutaneous tissues, the lungs, and the heart have been acceptable and are in full accordance with what have been reported in international literature.
This study matches global experience, which shows that patients with scleroderma and breast cancer must be discussed by the multidisciplinary tumor board in order for a personalized treatment strategy to be formulated. Radiation therapy can be proposed as a postsurgical therapeutic option in selected cases.
PMCID: PMC3846919  PMID: 24367188
breast radiotherapy; early toxicity; late complications; short review; scleroderma
3.  Reduction of Radiation Doses to Patients and Staff During Endoscopic Retrograde Cholangiopancreatography 
Endoscopic retrograde cholangiopancreatography (ERCP) is associated with a considerable radiation exposure for patients and staff. While optimization of the radiation dose is recommended, few studies have been published. The purpose of this study has been to measure patient and staff radiation dose, to estimate the effective dose and radiation risk using digital fluoroscopic images. Entrance skin dose (ESD), organ and effective doses were estimated for patients and staff.
Materials and Methods:
Fifty-seven patients were studied using digital X-ray machine and thermoluminescent dosimeters (TLD) to measure ESD at different body sites. Organ and surface dose to specific radiosensitive organs was carried out. The mean, median, minimum, third quartile and the maximum values are presented due to the asymmetry in data distribution.
The mean ESD, exit and thyroid surface dose were estimated to be 75.6 mGy, 3.22 mGy and 0.80 mGy, respectively. The mean effective dose for both gastroenterologist and assistant is 0.01 mSv. The mean patient effective dose was 4.16 mSv, and the cancer risk per procedure was estimated to be 2 × 10-5
ERCP with fluoroscopic technique demonstrate improved dose reduction, compared to the conventional radiographic based technique, reducing the surface dose by a factor of 2, without compromising the diagnostic findings. The radiation absorbed doses to the different organs and effective doses are relatively low.
PMCID: PMC3099076  PMID: 21196649
ERCP; radiation risk; staff exposure
4.  Peripheral dose measurement in high-energy photon radiotherapy with the implementation of MOSFET 
World Journal of Radiology  2010;2(11):434-439.
AIM: To study the peripheral dose (PD) from high-energy photon beams in radiotherapy using the metal oxide semiconductor field effect transistor (MOSFET) dose verification system.
METHODS: The radiation dose absorbed by the MOSFET detector was calculated taking into account the manufacturer’s Correction Factor, the Calibration Factor and the threshold voltage shift. PD measurements were carried out for three different field sizes (5 cm × 5 cm, 10 cm × 10 cm and 15 cm × 15 cm) and for various depths with the source to surface distance set at 100 cm. Dose measurements were realized on the central axis and then at distances (1 to 18 cm) parallel to the edge of the field, and were expressed as the percentage PD (% PD) with respect to the maximum dose (dmax). The accuracy of the results was evaluated with respect to a calibrated 0.3 cm3 ionization chamber. The reproducibility was expressed in terms of standard deviation (s) and coefficient of variation.
RESULTS: % PD is higher near the phantom surface and drops to a minimum at the depth of dmax, and then tends to become constant with depth. Internal scatter radiation is the predominant source of PD and the depth dependence is determined by the attenuation of the primary photons. Closer to the field edge, where internal scatter from the phantom dominates, the % PD increases with depth because the ratio of the scatter to primary increases with depth. A few centimeters away from the field, where collimator scatter and leakage dominate, the % PD decreases with depth, due to attenuation by the water. The % PD decreases almost exponentially with the increase of distance from the field edge. The decrease of the % PD is more than 60% and can reach up to 90% as the measurement point departs from the edge of the field. For a given distance, the % PD is significantly higher for larger field sizes, due to the increase of the scattering volume. Finally, the measured PD obtained with MOSFET is higher than that obtained with an ionization chamber with percentage differences being from 0.6% to 34.0%. However, when normalized to the central dmax this difference is less than 1%. The MOSFET system, in the early stage of its life, has a dose measurement reproducibility of within 1.8%, 2.7%, 8.9% and 13.6% for 22.8, 11.3, 3.5 and 1.3 cGy dose assessments, respectively. In the late stage of MOSFET life the corresponding values change to 1.5%, 4.8%, 11.1% and 29.9% for 21.8, 2.9, 1.6 and 1.0 cGy, respectively.
CONCLUSION: Comparative results acquired with the MOSFET and with an ionization chamber show fair agreement, supporting the suitability of this measurement for clinical in vivo dosimetry.
PMCID: PMC3006482  PMID: 21179311
Radiotherapy; Peripheral dose; Metal oxide semiconductor field effect transistor; Dosimeter
5.  Cytolytic T-cell response against Epstein-Barr virus in lung cancer patients and healthy subjects 
This study aimed to examine whether EBV seropositive patients with lung cancer have an altered virus-specific CTL response, as compared to age-matched healthy controls and whether any variation in this response could be attributed to senescence.
Peripheral blood mononuclear cells from lung cancer patients, age-matched and younger healthy individuals were used to measure EBV-specific CTLs after in vitro amplification with the GLCTLVAML and RYSIFFDYM peptides followed by HLA-multimer staining.
Lung cancer patients and aged-matched controls had significantly lesser EBV-specific CTL than younger healthy individuals. Multimer positive populations from either group did not differ with respect to the percentage of multimer positive CTLs and the intensity of multimer binding.
This study provides evidence that patients with lung cancer exhibit an EBV-specific CTL response equivalent to that of age-matched healthy counterparts. These data warrant the examination of whether young individuals have a more robust anti-tumor response, as is the case with the anti-EBV response.
PMCID: PMC2907867  PMID: 20525347

Results 1-5 (5)