Evaluation Of Secondary Malignancy Risk Due To The Whole Body Computerized Tomography Simulation In Radiotherapy Facilities

Nowadays, the use of computed tomography (CT) simulation is getting widespread with the use of new treatment modalities like three dimensional conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), adaptive radiotherapy (ART) and stereotactic radiosurgery (SRS) in radiotherapy facilities. The main purpose of these new treatment modalities are to increase the survival and increase the quality of life by reducing the side effects. However, radiation induced secondary malignancy risk is getting important after radiotherapy with the increase in survival. Especially, CT scanning was performed from head to sacral region for 3D-CRT craniospinal treatments techniques in children or young patients and several precautions should be taken to reduce the radiation dose due to the CT simulation. In this study, we measured organ equivalent dose in Alderson Rando phantom and we estimate radiation-induced cancer risk due to CT scanning for different conditions. According to our measurement, secondary malignancy risk was found to be between 0.10% - 0.22% for different conditions in craniospinal CT simulation.WoSScopu

Principles and Practice of Modern Radiotherapy Techniques in Breast Cancer

XV, 358 p. 91 illus., 84 illus. in color.online r

Radiation therapy for head and neck cancers: a case-based review

This evidence-based guide to the current management of cancer cases at all head and neck sites will assist in the appropriate selection and delineation of tumor volumes/fields for intensity-modulated radiation therapy (IMRT), including volumetric modulated arc therapy (VMAT). Each tumor site-related chapter presents, from the perspective of an academic expert, several actual cases at different stages in order to clarify specific clinical concepts. The coverage includes case presentation, a case-related literature review, patient preparation, simulation, contouring, treatment planning, treatment delivery, and follow-up. The text is accompanied by illustrations ranging from slice-by-slice delineations on planning CT images to finalized plan evaluations based on detailed acceptance criteria. The book will be of value for residents, fellows, practicing radiation oncologists, and medical physicists interested in clinical radiation oncology

Management of Ductal Carcinoma in Situ Patients Receiving Postoperative Radiotherapy After Breast Conserving Surgery: Hacettepe Experience

We retrospectively evaluated our therapetic results in ductal carcinoma in situ (DCIS) patients treated with postoperative radiotherapy following breast-conserving surgery (BCS). Sixty-seven DCIS patients were treated with curative radiotherapy (RT) after BCS, in our department from December 1998 to January 2008. All patients have been treated with 6 MV photon energy on lineer accelerator machine. Radiotherapy treatment fields were opposed tangential to the whole breast. A total dose of median 50 Gy (48-50 Gy) was delivered in five fractions in a week. In twenty patients, boost dose to the tumour region was applied. Fifty patients received systemic hormonotherapy. Median follow-up time was 44 moths (range 12-122 months). Five-year OS, DFS and local control rates were found as 96%, 97% and 97%, respectively. There was only one ipsilateral breast recurrence in our study (2%). Two patients died due to other causes except disease (3%). Grade III dermatitis was seen in only one patient (2%), and there was no serious acute side effects in 41 patients (63%). There was no late side effect in our patients. Sixty-two patients were alive without evidence of tumour recurrence, with their intact breast and with good cosmesis. Our survival rates and side effects were in consistent with literature, and RT is an effective option for DCIS patients following BCS.WoSScopu

Prognostic Significance Of Castrate Testosterone Levels For Patients With Intermediate And High Risk Prostate Cancer

BACKGROUND Testosterone level of < 50 ng/dL has been used to define castrate level after surgery or after androgen deprivation treatment (ADT) in metastatic prostate cancer (PC). AIM To evaluate the effect of two different castrate testosterone levels, < 50 and < 20 ng/dL, on biochemical relapse free survival (BRFS) in patients with non-metastatic intermediate and high risk PC receiving definitive radiotherapy (RT) and ADT. METHODS Between April 1998 and February 2011; 173 patients with intermediate and high risk disease were treated. Radiotherapy was delivered by either three-dimensional-conformal technique to a total dose of 73.4 Gy at the ICRU reference point or intensity modulated radiotherapy technique to a total dose of 76 Gy. All the patients received 3 mo of neoadjuvant ADT followed by RT and additional 6 mo of ADT. ASTRO Phoenix definition was used to define biochemical relapse. RESULTS Median follow up duration was 125 months. Ninety-six patients (56%) had castrate testosterone level < 20 ng/dL and 139 patients (80%) had castrate testosterone level < 50 ng/dL. Both values are valid at predicting BRFS. However, patients with testosterone < 20 ng/dL have significantly better BRFS compared to other groups (P = 0.003). When we compare two values, it was found that using 20 ng/dL is better than 50 ng/dL in predicting the BRFS (AUC = 0.63 vs 0.58, respectively). CONCLUSION Castrate testosterone level of less than 20 ng/dL is associated with better BRFS and is better in predicting the BRFS. Further studies using current standard of care of high dose IMRT and longer ADT duration might support these findings.PubMedWo

Radiation OncologyA MCQ and Case Study-Based Review /

XIV, 490p. 341 illus., 285 illus. in color.onlin

Dosimetric Comparison Of Three‐Dimensional Conformal Radiotherapy And Intensity‐Modulated Radiotherapy For Left‐Sided Chest Wall And Lymphatic Irradiation

Introduction The aim of this study was to compare five different techniques for chest wall (CW) and lymphatic irradiation in patients with left‐sided breast carcinoma. Methods Three‐dimensional conformal radiotherapy (3DCRT), forward‐planned intensity‐modulated radiotherapy (FP‐IMRT), inverse‐planned IMRT (IP‐IMRT; 7‐ or 9‐field), and hybrid IP‐/FP‐IMRT were compared in 10 patients. Clinical target volume (CTV) included CW and internal mammary (IM), supraclavicular (SC), and axillary nodes. Planning target volumes (PTVs), CTVs, and organs at risks (OARs) doses were analyzed with dose–volume histograms (DVHs). Results No differences could be observed among the techniques for doses received by 95% of the volume (D95%) of lymphatics. However, the FP‐IMRT resulted in a significantly lower D95% dose to the CW‐PTV compared to other techniques (P = 0.002). The 9‐field IP‐IMRT achieved the lowest volumes receiving higher doses (hotspots). Both IP‐IMRT techniques provided similar mean doses (Dmean) for the left lung which were smaller than the other techniques. There was no difference between the techniques for maximum dose (Dmax) of right breast. However, FP‐IMRT resulted in lower Dmean and volume of right breast receiving at least 5 Gy doses compared to other techniques. Conclusion The dose homogeneity in CW‐CTV was better using IMRT techniques compared to 3DCRT. Especially 9‐field IP‐IMRT provided a more homogeneous dose distribution in IM and axillary CTVs. Moreover, the OARs volumes receiving low radiation doses were larger with IP‐IMRT technique, while volumes receiving high radiation doses were larger with FP‐IMRT technique. Hybrid IMRT plans were found to have the advantages of both FP‐ and IP‐IMRT techniques.PubMedWoSScopu

Utility Of "Over D1" Or D1 Nodal Dissections In Predicting Outcome Of Patients With Gastric Adenocarcinoma Treated With Postoperative Concurrent Chemoradiotherapy

We retrospectively evaluated the utility "over D1" or D1 dissections on outcome of gastric cancer patients with subsequent postoperative chemoradiotherapy. Sixty-five patients with gastric adenocarcinoma treated with postoperative concurrent chemoradiotherapy were evaluated. Inclusion criteria were total or subtotal gastrectomy with a cut-point of >= 10 nodes dissected in the surgery without scheduled splenectomy and pancreatectomy. Nodal dissections grouped according to Japanese Research Society; N1 stations (1-6) as D1, and dissection of additional stations (7-9) as "over D1". The median follow-up was 30 months. Surgery was total gastrectomy in 32 patients and subtotal in 33. Nodal dissection was D1 in 36 (55.4%) patients and over D1 in 29 (44.6%). The 2-year overall, local recurrence free, distant metastasis free, and disease free survivals of the entire group of patients were 83.3%, 89.9%, 68.4%, 62.5% respectively. Two year distant metastasis free survival was %55 for D1 and %88.5 for "over D1" dissected patients (p= 0.06). Overall survival was significantly longer in "over D1" dissected patients (2 year overall survival: 72.3% for D1 and 96% for "over D1", p= 0.05). Moreover, disease specific survival was significantly longer in "over D1" dissected patients (2 year disease specific survival: 72.3% for D1 and 100% for "over D1", p= 0.02). No grade 3-4 acute or late toxicity was observed. In conclusion, our retrospective data showed that over D1 dissected patients treated with concomitant chemoradiotherapy seemed to gain additional survival benefit in comparison to D1 dissected patients in this retrospective cohort with no significant extra toxicity.WoSScopu