Purpose: To determine the optimal of three immobilisation devices for lung radiotherapy in terms of set-up reproducibility, patient comfort, radiation therapists’ (RTs) satisfaction and cost-effectiveness.

Materials and methods: A total of 30 lung CRT patients were randomised to one of three immobilisation techniques – Arm A, headsponge; Arm B, BreastBoard dedicated immobilisation device; and Arm C, LungBoard dedicated immobilisation device.

Results: Random errors were larger for Arm A versus C in all directions (p < 0.05). Random errors were larger for Arm A versus B for y and z directions (p < 0.05). When the data for the immobilisation devices (Arms B+C) were pooled and compared with Arm A (no dedicated device), the systematic errors were larger in the z direction for A (p < 0.05). Arm C was cheaper and was more comfortable for patients. Therapists preferred this device (Arm C) and treatment times were less (p < 0.05).

Conclusion: This is the first prospective randomised controlled lung immobilisation trial, based on 3-DCRT, that takes into account treatment accuracy, users satisfaction and resource implications. It suggests that the LungBoard immobilisation device is optimal.

Aim: To assess the efficacy of a probiotic preparation on the prevention of radiation-induced diarrhoea in cancer patients.

Methods: Group of 42 radio-oncology patients who had undergone adjuvant post-operative radiation therapy (RT) after abdominal and pelvic cancer were randomised to receive either the probiotic preparation “5” Strain Dophilus (twice per day; L-Group), or the preparation Hylak Tropfen Forte (40 drops, three times per day; H-Group). Supplementation started on the first day and lasted until the end of RT. Efficacy endpoints were the incidence and the severity of the radiation-induced diarrhoea. All patients received a paper form in which they recorded monitored parameters on a daily basis during RT.

Results: The mean daily number of bowel movements during the whole period was 4.16 in the L-Group and 2.52 in the H-Group; 62.5% of patients in L-Group and 81% in H-Group had a mean daily number of bowel movements of ≤4/day. Abdominal pain was recorded in 25% of the patients in L-Group and 22% of the patients in H-Group. Blood in the bowel movement was found in one patient from H-Group (9 days). Of patients in L-Group, 27% required diphenoxylate treatment during pelvic radiotherapy, compared with 55% in H-Group. Of patients from L-Group, 9% required antibiotics administration, compared with 25% in H-Group.

Conclusion: We concluded that the prophylactic probiotic therapy produced a highly favourable benefit/risk ratio. Supplementation with the probiotic preparation is an easy and safe approach to protect cancer patients from the risk of radiation-induced diarrhoea and carry out improvement in their quality of life.

We put forward the concept of the radiotherapy physics team as a community of practice (COP). Radiotherapy physicists are required to continuously develop their scientific, computational and management competencies. Much of this knowledge is gained through peer-to-peer interaction in a structured environment, enabling the individual to increase their tacit knowledge. Such interaction among peers will allow issues to be framed within their context, information to be shared, decisions to be made and protocols to be developed. The structure that allows physicists to create, share and manage knowledge conforms to the accepted definition of a COP. By implementing the methods of literature review and peer group survey, we have investigated the applicability of the concept of a radiotherapy physics COP. The results of the survey have shown a generally positive medical physicist training outlook in the UK and Germany, but highlighted certain areas where improvement is needed. Our surveys have shown that while most trainees are adequately supported, there are two areas where improvements can easily be made. Spatial factors, such as departmental geography, may not always be conducive to knowledge sharing but can readily be altered in most cases. The paucity of departmental seminars and journal club meetings has been highlighted as a problem at some training centres.

When upgrading treatment planning software, it is important to understand and characterise any changes that may have been made to the system. This includes inverse treatment planning and dose optimisation software used for intensity-modulated radiation therapy (IMRT). A systematic and practical approach to characterising dose optimisation software following upgrades is presented based on a planning study of six IMRT prostate cases using the commercial treatment planning system Oncentra Masterplan (OMP). Upgrades included general changes in the fluence to multileaf collimator (MLC) segmentation algorithm, a change from a two-step to a one-step optimisation method and an upgrade of the dose calculation algorithm. Post upgrade changes in plan parameters such as calculation times, monitor units, segments and target doses were analysed. A 32% reduction in total calculated monitor units was observed following the general software upgrade. A smaller 12% reduction was observed when using the optional one-step optimisation method rather than a two-step process using a classic dose calculation algorithm. An increase in monitor units of approximately 12% was observed when changing to an enhanced dose calculation algorithm. The enhanced dose calculation algorithm accounted for MLC type, leakage and source size unlike the previous classic dose calculation algorithm. Differences in dose to volumes between fluence segmentation and final dose calculation varied between versions. These differences were found to be minimal for the most recent treatment planning system version. Repeatability tests revealed a more effective use of the system. The characterisation of the effects of treatment planning software upgrades allowed a better appreciation of IMRT planning and delivery attributes. Although this work is based on one commercial inverse treatment planning system, it would be easily transferable to other systems as the underlying system principles are the same.

Background and Purpose: Intensity-modulated radiation therapy (IMRT) is considered by many to be the standard of care in the delivery of external-beam radiotherapy treatments to the prostate. The purpose of this study is to assess the validity of the purported benefits of IMRT.

Materials and Methods: Treatment plans were produced for 10 patients using both 3D conformal radiation therapy (3D-CRT) and IMRT, utilising the dose constraints recommended by the Radiation Therapy Oncology Group (RTOG) 0415 protocol. Three IMRT modalities used in this study were linear accelerator based IMRT, helical tomotherapy, and serial tomotherapy. The prescription to the target, 76 Gy, was the same for all plans.

Results: In general the 3D-CRT plans satisfied the RTOG criteria for planning target volume (PTV) coverage, and met or bettered the dose criteria for the organs at risk. PTV coverage was more homogeneous for the IMRT plans than the 3D-CRT plans but not significantly improved.

Conclusions: Technically, because the IMRT plans required greater effort for the optimisation, longer treatment times and higher monitor units, the use of IMRT for the fulfilment of the protocol’s dosimetric goals was not justified using these constraints.

The essential need for postoperative irradiation in people with carcinoma of the upper aerodigestive tract and limited metastatic nodal spread is controversial. An experience with postoperative radiotherapy in head and neck cancer (HNC) patients with one histologically positive cervical node is presented. Between 1976 and 2000, 37 individuals with confirmed metastatic disease in a single neck node underwent postoperative radiotherapy. The median follow-up period was 24 months. Among the 35 evaluable patients, the observed failure rates at the primary site, neck and distant location were 11%, 15% and 6%, respectively. The overall 5-year relapse-free survival rate was 60%. The relapse-free survival rate at 5 years was 86% in individuals who did not have additional histopathological risk factors and 55% in those patients who did (p = 0.46). The precise role of postoperative radiotherapy in people with HNC and documented metastasis in a single cervical lymph node remains to be defined including the identification of select individuals who may truly benefit from the combined therapy program.

A recurring theme from the literature is that the definition of reflection is nebulous and/or complex. Many authors have suggested that more research needs to be conducted to better understand an individual’s perception of reflection and reflective practice, and how these concepts affect their clinical practice as well as their personal growth and development. This paper offers the findings of a qualitative study of radiation therapists in Canada. The aim of the study was to explore radiation therapist’s understanding of the concept of reflection, and to understand how they incorporated it into their daily practice. Secondary objectives were to examine some of the perceived barriers to its use, and the possible challenges of implementing reflective writing. Two focus groups were initially conducted, and a follow-up questionnaire was developed using the themes generated from the focus groups. The questionnaire was distributed to radiation therapists at two large cancer centres in Toronto, Canada. Most participants indicated that it is an integral part of their practice and professional lives, and that they use a variety of different methods for engaging in reflection. It is not without its barriers, but many of these can be overcome by providing time, coaching and a supportive work environment. Respondents were divided as to whether they would benefit from being taught reflection; however, small group teaching would be the favoured method. Further study is suggested to determine whether there are any improvements to patient care and in particular patient outcomes.

A computer user-code (TRANSMIT), based on the use of the EGSnrc Monte Carlo system, was developed to simulate the transmission of megavoltage x-rays through three different materials used for shielding purposes in radiotherapy. These materials are Lipowitz’s metal, lead and Rad-block. The simulations were performed for 4, 6 and 10 MV x-rays using narrow beam geometry in air. The linear attenuation coefficients, in cm–1, obtained from the simulated transmission curves for Lipowitz’s metal were 0.494, 0.470 and 0.452 for 4, 6 and 10 MV, respectively. For lead, the linear attenuation coefficients were 0.532, 0.507 and 0.483 for 4, 6 and 10 MV, respectively. For Rad-block, the linear attenuation coefficients were 0.561, 0.537 and 0.518 for 4, 6 and 10 MV, respectively. Comparison of the simulation results with experimental results reported in the literature gave a percent deviation <5% which indicates the validity of the simulation results. In addition, broad beam geometry calculations were performed for a variety of field sizes (10 × 10 cm2, 20 × 20 cm2 and 40 × 40 cm2) using the three different attenuators. The results showed that broad beam attenuation coefficients decreased with increased field size and photon energy. For Lipowitz’s metal, the difference in the linear attenuation coefficient data between the broad beam attenuation coefficient and the narrow beam value lies between 3.6% and 20% depending on x-ray energy and field size. Similarly, the difference between the broad beam attenuation coefficient and the narrow beam value for lead lies between 1.5% and 10.4%. For the Rad-block material, the difference lies between 0.53% and 6.8%.

Purpose: To assess the efficiency of an integrated imaging, planning, and treatment delivery system to provide image-guided intensity-modulated radiotherapy (IG-IMRT) for patients requiring palliative radiotherapy (PRT).

Methods: Between December 2006 and May 2008, 28 patients requiring urgent PRT were selected to undergo single-session megavoltage computed tomography (MV-CT) simulation, IMRT treatment planning, position verification and delivery of the first faction of radiotherapy on a helical Tomotherapy® unit. The time required to complete each step was recorded and compared to our standard approach of using either fluoroscopic or CT-based simulation, simplified treatment planning and delivery on a megavoltage unit.

Results: Twenty-eight patients were treated with our integrated IG-IMRT protocol. The median age was 72 years, with 61% men and 39% women. The indications for PRT were: painful bone and soft tissue metastasis (75%); bleeding lesions (14%); and other reasons (11%). The areas treated included the following: hip and/or pelvis (42%); spine (36%); and other areas (21%). The most commonly used dose prescription was 20 Gy in five fractions. Average times for the integrated IG-IMRT processes were as follows: image acquisition, 15 minutes; target delineation, 16 minutes; IMRT treatment planning, 9 minutes; treatment position verification, 10 minutes; and treatment delivery, 12 minutes. The average total time was 62 minutes compared to 66 minutes and 81 minutes for fluoroscopic and CT-simulation-based approaches, respectively. The IMRT dose distributions were also superior to simpler plans.

Conclusions: PRT with an integrated IG-IMRT approach is efficient and convenient for patients, and has potential for future applications such as single-fraction radiotherapy.

Radiosensitive neurogenic stem cells reside in the hippocampi, suggesting that avoidance of the hippocampi may be an important strategy to reduce potential radiation-related cognitive effects. Six patients treated for base of skull tumours were re-planned using co-planar helical fan beam arc therapy (tomotherapy) and co-planar and non-coplanar volumetric arc techniques (RapidArc). The hippocampi were contoured as avoidance structures with the specific goal of minimising the dose. Two gross target volume (GTV) to planning target volume (PTV) expansions (10 and 2 mm) were considered to evaluate the impact of margin selection on organ at risk (OAR) sparing. The dose prescription was 50 Gy to >95% of the PTV. Comparison of the hippocampus avoidance plans demonstrated the importance of non-coplanar delivery when the 10 mm margin was used. With the 2 mm margin, both co-planar and non-coplanar delivery provided similar degrees of sparing. A mean dose of 3–4 Gy and a V6Gy <5% to the hippocampi was realised with the hippocampus sparing techniques. Our comparisons suggest interventions to minimise GTV to PTV margins will have a more profound influence on multiple OAR sparing than the choice of intensity modulated arc delivery technique.

Purpose: To look for the therapeutic benefit of radiotherapy after surgery in patients with T1–T2 breast tumour.

Methodology: From 1990 to 2000, 915 patients with T1–T2 breast tumour who underwent mastectomy or conservative breast surgery (CBS) with or without radiotherapy were analysed retrospectively for age, disease stage, radiation therapy technique, dose, the use of chemotherapy or hormonal therapy and other clinical and/or pathologic characteristics. The Kaplan–Meier method was used to estimate locoregional recurrence-free survival (LRRFS) and overall survival (OS). The Cox proportional hazard regression model was used to determine significant prognostic factors affecting LRRFS and OS.

Results: At a median follow up of 74 months, LRR rate was 5.3% and distant metastases rate was 19%. Disease-free survival (DFS) and OS at 10 year was 72% and 76%, respectively. LRR in patients with CBS followed with radiation was 3% as compared to 33% without radiation. LRR in patients with post-mastectomy radiation was 3% as compared to 19% without radiation. In patients with N0 nodes, LRR was 4% with radiation and 20% without radiation. Worst case was in patients with CBS-N0 who were not given radiation. LRR in such patients was 32% as compared to 5% in those who were given radiation post-CBS. In patients with mastectomy with N0 status, LRR was 3% with radiation as compared to 18% with out radiation. On univariate analysis factors affecting LRRFS were type of surgery, nodal involvement, radiotherapy and hormonal therapy. Factors affecting OS were nodal involvement, grade, lymphovascular invasion (LVI), ductal carcinoma in situ (DCIS), extracapsular extension (ECE), chemotherapy and radiotherapy. On multivariate analysis factors affecting LRRFS were type of surgery, nodal involvement, radiotherapy and hormonal therapy. Factors affecting OS were nodal involvement, LVI, DCIS, ECE, chemotherapy and radiotherapy.

Conclusion: Radiation use offered a therapeutic advantage for all patients with T1–T2 breast cancer.

In radiotherapy, the radiation beam is sometimes shaped so as to deliver different doses to different organs or give a homogeneous dose to structures of different densities. This objective is achieved by the use of attenuating materials introduced into the radiation beam. These attenuators alter the primary as well as the scattered radiation components of the beam and there is at present no accurate method of dose calculation for these situations. Most calculations are performed considering only the effect of the attenuators on the primary radiation beam and can produce large errors in dosimetry. In this study, the broad-beam attenuation is investigated in homogeneous phantoms for various radiation field sizes, photon beam energies and depths in phantom. A mathematical method taking account of primary as well as first scattered radiation is developed. This method predicts reasonably well the transmission through lead attenuators for various experimental conditions.

Purpose: Conformal radiotherapy of the prostate is an increasingly common technique in the treatment of prostate cancer. When using 3D conformal radiotherapy (CFRT) methods, it is desirable to protect the vital structures such as bladder, rectum, and femur. In this study, our aim was to compare the femur head doses resulting from co-planar beam arrangements in four-field (4F), five-field (5F), six-field (6F) and seven-field (7F) treatment plans, in a dose-escalated CFRT schedule.

Materials and Methods: From January 2005 to December 2006, at Istanbul University Medical Faculty of Radiation Oncology Clinic, a total of 22 patients with carcinoma of the prostate had been scanned using computed tomography (CT) (0.50 mm) in the supine position. During the CT scanning which used the Sim Pro (CMD–USA) programme, planned target volume (PTV), clinical target volume (CTV), and dose volumes received by the bladder, rectum and femur heads were recorded and dose–volume histogram (DVH) were created. The dose volume relating to prostate and seminal vesicles was termed CTV 1, and the dose volume relating to prostate alone was termed CTV 2. During the formation of PTV, into CTV 1, from the anterior-superior-inferior 8 mm, and from posterior 5 mm tolerance were taken into account. After volume determination is calculated using XiO (CMS-USA) 3D treatment planning computer, each patient 4F (45° – 25%, 135° – 25%, 225° – 25%, 315° – 25%), 5F (0° – 20%, 45° – 20%, 90° – 20%, 270° – 20%, 315° – 20%), 6F (45° – 20%, 90° – 10%, 135° 20%, 315° – 20%, 270° – 10%, 225° – 20%) and 7F (0° – 4%, 45° – 12.9%, 90° – 22.2%, 135° – 12.9%, 315° – 12.9%, 270° – 22.2%, 225° – 12.9%) was entered; 70 – 76 Gy was calculated to be given to prostate lodge. With the use of Siemes Oncor, 18 MV photons CFRT was applied. In DVH analysis, following were observed: V50, minimum and maximum doses for head of left femur and right femur total doses.

Results: Our statistical evaluation was made using SPSS software, and we found femur doses following; 4F V50 1030 cGy (minimum 58, maximum 1390), 5F V50 2425 cGy (minimum 540, maximum 3631), 6F V50 1769 cGy (minimum 1234, maximum 3912) and 7F V50 3230 cGy (minimum 2150, maximum 4137). In comparing different techniques, the greatest rectal sparing was achieved by the 5F plan. (Rectal: 5F V%25 = 59.90 ± 6.8 Gy, 4F V%25 = 62.30 ± 10.3 Gy, 6F V%25 = 69.36 ± 5.7 Gy, 7F V%25 = 61.32 ± 7.3 Gy). The greatest femoral head sparing was achieved by the 4F techniques. When paired samples t-test was made, we found considerable lower femur doses for 4F techniques (p = 0.05).

Conclusion: We concluded that, during radiotherapy to treat carcinoma of the prostate, the dose received by the rectum is the most important factor to consider, given the potential for late toxicity in this organ. However, while using lateral fields (90–270°) so as to protect the rectum, the doses received by the femur heads were observed to be higher. Especially in older patients, the critical doses of 52 Gy for TD5/5 and 65 Gy for TD 50/5 were observed to be not reached late toxicity for 4F, 5F, 6F and 7F.

Purpose: To determine the pattern of care and survival in older patients with breast cancer.

Methods: The study population included 228 women aged ≥60 years with breast cancer treated between 1992 and 2002. Analysis was done for surgery, radiotherapy (RT), chemotherapy and hormonal therapy. Outcomes studied were locoregional recurrence (LRR) distant metastases, disease-free survival (DFS) and overall survival (OS) using univariate and multivariate analyses. Kaplan–Meier method was used to estimate DFS and OS.

Results: Mastectomy was done in 208 (91%) patients and conservative breast surgery (CBS) only in 20 (9%) patients. Majority of the patients received adjuvant RT 179 (78.5%). Chemotherapy was given to 49 (21.5%) patients and hormones to 204 (89.5%) patients. LRR with or without distant metastases was 7% and distant metastasis rate was 19.3%. DFS at 10 years was 69%. With RT, DFS was 76% in patients aged <65 years and 73% in aged ≥65 years (p = 0.13). It was 73 and 86%, respectively, with chemotherapy (p = 0.041). DFS with hormones was 96% in patients aged ≥65 years and 79% in aged <65 years (p = 0.028). The OS was 74% at 10 years. RT improved OS in all patients. OS with chemotherapy was 94% in patients ≥65 years, and 82% in patients <65 years (p = 0.044). With hormonal therapy OS was 96% in patients aged ≥65 years and 78% in patients <65 years (p = 0.020).

Conclusion: CBS rate and chemotherapy use is very low in elderly women with breast cancer in India. Adjuvant RT, chemotherapy and hormonal therapy offered a therapeutic advantage in these patients.

Objective: Complications of pelvic irradiation for rectal cancer have gained more attention because of increased survival of patients. The aim of this study was to compare testes doses when pelvis is irradiated using Cobalt 60 (Co60) for rectal cancer in comparison with linear accelerator (LINAC) and its effect on sex hormones levels.

Materials and Methods: In a cohort study, 28 rectal cancer patients that were candidate to receive pelvic radiotherapy were recruited in the study consecutively. They were sequentially assigned to receive radiotherapy using Co60 teletherapy or LINAC. Serum sex hormones levels were measured before and 3–6 weeks after irradiation. Testes absorption doses were measured three times during whole course of irradiation in nine patients.

Results: Testes doses in LINAC group were significantly lower than Co60 group (p < 0.001). Serum follicular-stimulating hormone (FSH) and luteinising hormone (LH ) levels increased after irradiation in both groups and there was not a significant relation between FSH and LH levels with treatment machine (p < 0.2 and p < 0.6, respectively). Serum testosterone level decreased significantly in Co60 group (p < 0.05) but not in LINAC group (p < 0.3).

Discussion: It seems using LINAC for pelvic irradiation in patient with rectal cancer cannot prevent hormonal changes and we suggest using extra shield to decrease testes doses below the toxic levels.