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Aims and Background: The aim of the study was to analyze the dose to be administered with two-dimensional involved-field palliative radiotherapy in advanced pancreatic carcinoma with respect to current dose-volume constraints (QUANTEC)., Methods and Study Design: The following standard regimens were evaluated: 30 Gy at 3 Gy/fraction (regimen A), 36 Gy at 2.4 Gy/fraction (regimen B), 45 Gy at 1.8 Gy/fraction (regimen C), and 50 Gy at 2 Gy /fraction (regimen D). The following constraints were considered: spinal cord Dmax <50 Gy, duodenum Dmax <55 Gy, liver Dmean <30 Gy, kidneys Dmean <15 Gy. For dose/fraction different from 1.8-2 Gy, the correction of constraints using a value of alpha/beta = 3 for late effects was considered. The calculation of dose/volume constraints was repeated for three different radiation beams: cobalt unit, 6 MV photons, and 15 MV photons. Standard field sizes were used and adapted according to the different beam types, using the parameters of our previous study. Respect of dose-volume constraints was assessed for each type of beam and treatment (dose per fractionation) in all patients. Treatments were considered acceptable in case of: 1) respect of the constraints for spinal cord and duodenum in all patients; 2) respect in >10/15 patients of constraints for kidneys and liver. Therefore, minor violations (<10%) of the constraints for these organs were accepted (in less than 5/15 patients), in consideration of the palliative aim of treatment., Results: In regimen A (30 Gy, 3 Gy/fraction), evaluated constraints were respected in all patients, regardless of the type of energy. In regimen B (36 Gy, 2.4 Gy/fraction), constraints were met in all patients undergoing irradiation with 6 and 15 MV photons. However, using the cobalt unit, kidney constraint was respected only in 5 of 15 patients. In regimens C and D (45 Gy, 1.8 Gy/fraction and 50 Gy, 2 Gy/fraction, respectively), the constraint for the kidney was respected only in 2-5 patients, depending on the energy used. Furthermore, using 50 Gy, the spinal cord constraint was not respected in 2-3 patients, depending on the beam used. Therefore, only the following treatments were considered acceptable: 1) 30 Gy, 3 Gy/fraction, regardless of the energy used; 2) 36 Gy, 2.4 Gy/fraction, only for treatments performed with linear accelerator (6-15 MV)., Conclusions: The clinical benefits of radiotherapy in pancreatic tumors should not be withheld from patients treated in centers only with two-dimensional technology. Prospective trials, particularly in developing countries, would be useful to evaluate the efficacy in this setting of involved-field two-dimensional treatments using the dose and fractionation defined in this analysis.

Aims and Background: The aim of this report was to investigate the feasibility in terms of treatment time prolongation of an on-line no-action level correction protocol, based on daily electronic portal image verification., Methods and Study Design: The occupation of a linear accelerator (LINAC) delivering 3-D conformal treatments was monitored for two weeks (from Monday to Friday, 10 working days). An electronic portal image device I-View (Elekta, UK) was used for setup verification. Single-exposure portal images were acquired daily using the initial 8 monitor units delivered for each treatment field. Translational deviations of isocenter position larger than 5 mm or 7 mm, for radical or palliative treatments, respectively, were immediately corrected. In order to estimate the extra workload involved with the on-line protocol, the time required for isocenter check and table correction was specifically monitored., Results: Forty-eight patients were treated. In all, 482 fractions had electronic portal images taken. Two hundred and forty-five setup corrections were made (50.8% of all fractions). The occupation of the LINAC lasted 106 h on the whole. Twelve h and 25 min (11.7% of LINAC occupation time) were spent for portal image verification and setup correction. On the average, 4.3 fractions per hour were carried out., Conclusions: When used by trained therapists, ideally, portal imaging may be carried out before each fraction, requiring approximately 10% of LINAC occupation time.

A 77-year-old male patient with unresected malignant pleural mesothelioma, clinical stage T3N0M0 according to the New International Staging System for Diffuse Malignant Pleural Mesothelioma, received intensity-modulated radiotherapy (IMRT) with a simultaneous integrated boost (SIB) after 6 cycles of chemotherapy with cisplatin and pemetrexed. SIB-IMRT delivered 40.5 Gy (1.5 Gy/fraction) to the left pleura and 50 Gy (1.85 Gy/fraction) to the sites of macroscopic disease. Radiotherapy was well tolerated. Two months after the end of radiotherapy the patient showed grade 2 lung toxicity (febrile episodes accompanied by dry cough) that was successfully treated with steroid therapy. Local control lasted for 2 years after SIB-IMRT. Then the tumor recurred marginally to the radiation field and the patient underwent chemotherapy with pemetrexed. Three years from the diagnosis, the patient is alive and in good general condition. He only takes prednisone 5 mg/daily for exertional dyspnea. To the best of our knowledge this is the first reported use of SIB-IMRT in unresected malignant pleural mesothelioma. Considering the dosimetric advantages of SIB-IMRT and the clinical results observed in our patient, additional evaluation of this technique seems justified.

Aims: To investigate the technical feasibility of utilizing the Active Breathing Coordinator for planning of postoperative three-dimensional conformal radiation therapy in patients with early stage breast cancer undergoing breast conservation therapy., Methods: Patients with early stage breast cancer for whom adjuvant radiotherapy after breast-conserving surgery was planned were consecutively enrolled. Five sessions of simulation with the Active Breathing Coordinator were planned for each patient. Computed tomography for simulation was not acquired until a good level of compliance with the procedure was achieved by the patient. Patients who did not show a satisfactory level of compliance after the planned fifth session were defined as noncompliant. Two simulation computed tomography scans were acquired: the first without the Active Breathing Coordinator during free breathing, the second with the Active Breathing Coordinator. Forward intensity-modulated treatment plans were calculated. Mean lung dose (MLDipsilateral) and V30 (V30lung) for the ipsilateral lung and V30 for the heart (V30heart), were evaluated., Results: Twenty consecutive patients were enrolled (6 with left-sided breast cancer and 14 with right-sided breast cancer). Eighteen of the patients completed the simulation computed tomography with the Active Breathing Coordinator after 1-5 sessions (median, 3). In 16 of the 18 patients, a reduction of V301ung was observed with the Active Breathing Coordinator. In 15 of the 18 patients, a reduction of MLDipsiateral was also observed. In 5 of the 6 patients with left-sided breast cancer, a reduction of V30heart was noted., Conclusions: Routine application of the Active Breathing Coordinator in clinical practice is feasible, even though it requires an increased workload. Dosimetric results are encouraging in terms of a better sparing of the ipsilateral lung and the heart.

The occurrence of renal carcinoma metastasis to the head and neck region is extremely rare. Some authors have reported metastasis of renal cell carcinoma to the parotid glands, nose and paranasal sinus, tongue, larynx, thyroid and palatine tonsil. In this report we describe a rare case of renal cell cancer metastasized to the right tonsil in a 76-year-old man with previously diagnosed bone and lung metastases. To the best of our knowledge this is the first documented example of radiotherapy treatment in this type of presentation. Radiotherapy was effective in treating the lesion with satisfactory functional results.