This work compares dose-volume constraints (DVCs) and tumour control predictions based on the average intensity projection (AVIP) to those on each phase of the four-dimensional computed tomography.

In this prospective study plans generated on an AVIP for nine patients with locally advanced non-small-cell lung cancer were recalculated on each phase. Dose-volume histogram (DVH) metrics extracted and tumour control probabilities (TCP) were calculated. These were evaluated by Bland–Altman analysis and Pearson Correlation.

The largest difference between clinical target volume (CTV) on the individual phases and the internal CTV (iCTV) on the AVIP was seen for the smallest volume. For the planning target volume, the mean of each metric across all phases is well represented by the AVIP value. For most patients, TCPs from individual phases are representative of that on the AVIP. Organ at risk metrics from the AVIP are similar to those seen across all phases.

Utilising traditional DVH metrics on an AVIP is generally valid, however, additional investigation may be required for small target volumes in combination with large motion as the differences between the values on the AVIP and any given phase may be significant.

Breast cancer is the most commonly diagnosed cancer among women and the second leading cause of cancer-related death in Canadian women. Surgery is often the first line of treatment for low-risk early stage patients, followed by adjuvant radiation therapy to reduce the risk of local recurrence and prevent metastasis after lumpectomy or mastectomy. For high-risk patients with node positive disease or are at greater risk of nodal metastasis, radiation therapy will involve treatment of the intact breast or chest-wall as well as the regional lymph nodes.

We retrospectively evaluated the treatment plans of 354 patients with breast cancer with nodes positive or were at high risk of nodal involvement treated at our cancer centre. All patients were treated with a prescription dose of 50 Gy in 25 fractions to the intact breast or chest-wall and 50 Gy in 25 fractions to the supraclavicular region and, based on patient suitability and tolerance, were treated either using the deep inspiration breath hold (DIBH) or free-breathing (FB) techniques.

Based on patient suitability and tolerance, 130 (36·7%) patients were treated with DIBH and 224 (63·3%) with FB techniques. There were 169 (47·7%) patients treated with intact breast, whereas 185 (52·3%) were treated for post-mastectomy chest-wall. The mean PTV_eval V92%, V95%, V100% and V105% for all patients are 99·4 ± 0·7, 97·6 ± 1·6, 74·8 ± 7·9 and 1·5 ± 3·2%, respectively. The mean ipsilateral lung V10Gy, V20Gy and V30Gy are 30·0 ± 5·3, 22·4 ± 4·7 and 18·4 ± 4·3% for intact breast and 30·9 ± 5·8, 23·5 ± 5·4 and 19·4 ± 5·0% for post-mastectomy patients with FB, respectively. The corresponding values for patients treated using DIBH are 26·3 ± 5·9, 18·9 ± 5·0 and 15·6 ± 4·7% for intact breast and 27·5 ± 6·5, 20·6 ± 5·7 and 17·1 ± 5·2% for post-mastectomy patients, respectively. The mean heart V10Gy, V20Gy, is 1·8 ± 1·7, 0·9 ± 1·0 for intact breast and 3·1 ± 2·2, 1·7 ± 1·6 for post-mastectomy patients with FB, respectively. The corresponding values with the DIBH are 0·5 ± 0·7, 0·1 ± 0·4 for intact breast and 1·1 ± 1·4, 0·4 ± 0·7 for post-mastectomy patients, respectively.

The use of 3 and/or 4 field hybrid intensity-modulated radiation therapy technique for radiation therapy of high-risk node positive breast cancer patients provides an efficient and reliable method for achieving superior dose uniformity, conformity and homogeneity in the breast or post-mastectomy chest-wall volume with minimal doses to the organs at risk. The development and implementation of a consistent treatment plan acceptability criteria in radiotherapy programmes would establish an evaluation process to define a consistent, standardised and transparent treatment path for all patients that would reduce significant variations in the acceptability of treatment plans.

Malignant spinal cord compression (MSCC) is a serious condition requiring urgent palliative radiotherapy to alleviate symptoms and avoid permanent paralysis. This audit compares the number of patients treated for MSCC before and during Covid-19, their treatment regimes and 30-day mortality rates to assess if the pandemic affected the treatment and the number of patients referred for palliative radiotherapy.

A retrospective audit was performed (July–December 2019) and 101 patients were treated for MSCC, an average of 17 patients per month. A further audit was undertaken during Covid-19 (March–May 2020) and 36 patients were treated for MSCC, an average of 12 patients per month in this shorter cohort.

The results have demonstrated fewer patients presenting during the pandemic and this may be due to patients not wishing to utilise the National Health Service (NHS) during this time. It also highlighted the need to reduce the treatment duration to minimise hospital attendance and lessen the potential for exposure to Covid-19.

Educating patients at risk of MSCC is essential and all cancer patients should be counselled on symptoms and what to do if they occur. Ensuring clinicians know the warning signs and the referral pathway for MSCC is also key to ensure early presentation and early referral for treatment.

To compare tumour dose distribution, conformality, homogeneity, normal tissue avoidance, tumour control probability (TCP) and normal tissue complication probability (NTCP) using 3D conformal radiation therapy (3DCRT), 3- and 4-field intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) in patients with locally advanced rectal cancer.

Twenty-four patients staged T1–3N+M0 with locally advanced rectal cancer underwent neoadjuvant chemoradiation therapy. Four different radiotherapy plans were prepared for each patient: 3DCRT, 3- and 4-field IMRT and VMAT are evaluated for target distribution using CI and homogeneity index (HI), normal tissue avoidance using Dmax, V45, V40, V50 and TCP and NTCP using the Lyman–Kutcher–Burman model.

VMAT has better HI (HI = 1·32) and 3DCRT exhibited better conformality (CI = 1·05) than the other radiotherapy techniques. With regard to normal tissue avoidance, all radiotherapy plans met the constraints. Dmax in the 3DCRT plans was statistically significant (p = 0·04) for bladder and no significant differences in V40 and V50. In the bowel bag, no significant differences in Dmax for any radiotherapy plan and V40 was lower in 3DCRT than VMAT (p = 0·024). In the case of femoral heads, 3DCRT has a statistically significant lower dose on Dmax than 4-field IMRT (p = 0·00 « 0·05). VMAT has the biggest TCP (80·76%) than the other three radiotherapy plans. With regard to normal tissue complications, probabilities were shown to be very low, of the order of 10-14 and 10-41 for bowel bag and femoral heads respectively.

It can be concluded that 3DCRT plan improves conformity and decreases radiation sparing in the organ at risks, but the VMAT plan exhibits better homogeneity and greater TCP.

To evaluate the patterns of recurrence following postoperative conformal radiotherapy (RT) for intracranial meningioma.

Eighty-six patients who received conformal RT for intracranial meningiomas from 2014 to 2017 were retrospectively analysed. For documented recurrences, recurrence imaging was deformably co-registered to planning CT scan. In-field recurrence was defined as recurrence within the 90% isodose line, and out-of-field recurrences were those that occurred outside the 90% isodose line. We present the demographic details, surgical and RT details, outcomes and patterns of recurrence.

The median age was 46 years (range 17–72); 82·6% underwent surgery [46·5% had subtotal resection (STR), 43·7% gross tumour resection (GTR), 5·6% biopsy] and 17·4% had no surgery. Among these, 53·5% were WHO grade 2; 27·9% grade 1; and 1·2% grade 3 meningioma. Fifty per cent received stereotactic RT (SRT), 46·5% 3D conformal RT (3DCRT) and 3·5% intensity-modulated RT (IMRT). The mean clinical target volume (CTV) and planning target volume (PTV) margins were 4·5 mm (range 0–15) and 3·9 mm (range 1–5), respectively. The doses ranged from 54 to 59·4 Gy. The median follow-up after RT was 1·7 years (range 0·2–4·7). 17·4% were lost to follow-up, 5·4% had recurrence, and the median time to recurrence after completion of RT was 2 years (range 0·7–2·9). The 3-year recurrence-free rate was 81·5%. Three patients had in-field and two had in-field and out-of-field recurrence. Among the cases with recurrence, three received SRT, one 3DCRT and one IMRT. Four were grade 2 and one was grade 3 tumour, and the CTV margin ranged from 0 to 5 mm, and the PTV margin ranged from 3 to 5 mm.

Local recurrence was seen in grade 2 and 3 meningiomas. SRT probably had more recurrence as they had lesser CTV margin. Increased CTV margin, escalated dose up to 59·4 Gy and 3DCRT/IMRT may be helpful in preventing local recurrences in grade 2 and grade 3 meningiomas.

To report 5- and 10-year overall survival (OS) outcomes of squamous cell carcinoma of the head and neck and identify prognostic factors.

Data on 2,095 patients at Maharaj Nakorn Chiang Mai Hospital, Thailand between 2007 and 2014 were analysed using the Kaplan–Meyer method to estimate 5- and 10-year OS rates. Cox proportional hazard regression models were applied to assess the independent prognostic factors of survival.

8·7% had hypopharyngeal cancer, 19·7% laryngeal, 53·3% oral cavity and 18·3% oropharyngeal. Two-thirds of the patients had locally advanced stage (III–IVB). Five- and ten-year OS rates were 30·1 and 22·8%, respectively.

Cancer site, stage and age at diagnosis were associated with mortality, highlighting the importance of prevention and early detection.

The aim of this study was to investigate the extent to which lung stereotactic body radiotherapy (SBRT) treatment plans can be improved by replacing conventional flattening filter (FF) beams with flattening filter-free (FFF) beams.

We selected 15 patients who had received SBRT with conventional 6-MV photon beams for early-stage lung cancer. We imported the patients’ treatment plans into the Eclipse 13·6 treatment planning system, in which we configured the AAA dose calculation model using representative beam data for a TrueBeam accelerator operated in 6-MV FFF mode. We then created new treatment plans by replacing the conventional FF beams in the original plans with FFF beams.

The FFF plans had better target coverage than the original FF plans did. For the planning target volume, FFF plans significantly improved the D98, D95, D90, homogeneity index and uncomplicated tumour control probability. In most cases, the doses to organs at risk were lower in FFF plans. FFF plans significantly reduced the mean lung dose, V10, V20, V30, and normal tissue complication probability for the total lung and improved the dosimetric indices for the ipsilateral lung. For most patients, FFF beams achieved lower maximum doses to the oesophagus, heart and the spinal cord, and a lower chest wall V30.

Compared with FF beams, FFF beams achieved lower doses to organs at risk, especially the lung, without compromising tumour coverage; in fact, FFF beams improved coverage in most cases. Thus, replacing FF beams with FFF beams can achieve a better therapeutic ratio.

Vestibular schwannomas (VS) are benign slow-growing tumours treated either with microsurgery or stereotactic radiosurgery (SRS) or both. The aim of this study was to correlate the outcome factors—tumour control and adverse factors—facial nerve function and hearing loss with patient and treatment factors.

A retrospective review of the records of 98 patients with 99 VS treated from June 2007 to June 2014, all patients receiving Linear Accelerator (LINAC)-based SRS.

Median follow-up period was 5·6 years (range: 1–12 years). The response to treatment was stable disease in 37 (37·4%), regression in 46 (46·5%), asymptomatic minimal progression in 9 (9·1%) and symptomatic progression in 5 (5%) and unknown in 2 (2%) patients. There was no evidence of SRS induced tissue damage on magnetic resonance scans for any. Hearing preservation rate after SRS was 92%. The patients who developed worsening of facial function were predominantly in the cohort that had prior surgery.

SRS is an effective modality to treat VS lesser than 3 cm in size. Tumour control rate was 95% with a median follow-up period of 5·6 years. The complication rates were 8% each for facial function worsening and worsening of hearing. Prior surgery was a statistically significant factor that affected facial nerve function deterioration.

The standard treatment modalities for prostate cancer include surgery, chemotherapy, hormonal therapy and radiation therapy or any combination depending on the stage of the tumour. Radiation therapy is a common and effective treatment modality for low-intermediate-risk patients with localised prostate cancer, to treat the intact prostate and seminal vesicles or prostate bed post prostatectomy. However, for high-risk patients with lymph node involvement, treatment with radiation will usually include treatment of the whole pelvis to cover the prostate and seminal vesicles or prostate bed and the pelvic lymph nodes followed by a boost delivery dose to the prostate and seminal vesicles or prostate bed.

We retrospectively analysed the treatment plans for 179 prostate cancer patients treated at the cancer centre with the volumetric-modulated arc therapy (VMAT) technique via RapidArc using 6 MV photon beam. Patients were either treated with a total prescription dose of 78 Gy in 39 fractions for patients with intact prostate or 66 Gy in 33 fractions for post prostatectomy patients.

There were 114 (64%) patients treated with 78 Gy/39 and 65 (36%) treated with 66 Gy/34. The mean homogeneity index (HI), conformity index (CI) and uniformity index (UI) for the PTV-primary of patients treated with 78 Gy are 0.06 ± 0.01, 1.04 ± 0.01 and 0.99 ± 0.01, respectively, and the corresponding mean values for patients treated with 66 Gy are 0.06 ± 0.02, 1.05 ± 0.01 and 0.99 ± 0.01, respectively. The mean PTV-primary V95%, V100% and V105% are 99.5 ± 0.5%, 78.8 ± 12.2% and 0.1 ± 0.5%, respectively, for patients treated with 78 Gy and 99.3 ± 0.9%, 78.1 ± 10.6% and 0.1 ± 0.4%, respectively, for patients treated with 66 Gy. The rectal V50Gy, V65Gy, V66.6Gy, V70Gy, V75Gy and V80Gy are 26.8 ± 9.1%, 14.2 ± 5.3%, 13.1 ± 5.0%, 10.8 ± 4.3%, 6.9 ± 3.1% and 0.1 ± 0.1%, respectively, for patients treated with 78 Gy and 33.7 ± 8.4%, 14.1 ± 4.5%, 6.7 ± 4.5%, 0.0 ± 0.2%, 0.0% and 0.0%, respectively, for patients treated with 66 Gy.

The use of VMAT technique for radiation therapy of high-risk prostate cancer patients is an efficient and reliable method for achieving superior dose conformity, uniformity and homogeneity to the PTV and minimal doses to the organs at risk. Results from this study provide the basis for the development and implementation of consistent treatment criteria in radiotherapy programs, have the potential to establish an evaluation process to define a consistent, standardised and transparent treatment path for all patients that reduces significant variations in the acceptability of treatment plans and potentially improve patient standard of care.

This study reveals the characteristic nature and the use of optically stimulated luminescence dosimeters (OSLD) as an in vivo dosimetry tool for head and neck intensity-modulated radiation therapy (IMRT).

Calibration and characterisation of OSLD such as sensitivity, reproducibility, dose-rate dependence, beam quality dependence, output factor measurement and comparison of two bleaching techniques using halogen and compact fluorescent lamp (CFL) were initially performed. Later, eye dose measurements were performed for head and neck IMRT patients using OSLD and were compared with the corresponding dose calculated by the treatment planning system (TPS).

While the sensitivity was found to be within ±5%, the dose-rate dependence and reproducibility were found to be within ±3%. The OSLD showed an under-response of 3% for 15 MV and an increase in response by 5% for Co60 (1·25 MeV) when compared with the 6 MV X-ray beam. Therefore, a separate calibration for different beam energies is required. The percentage deviation of OSLD to that of TPS was found to be within ±2·77%. The OSLD has been successfully used for the in vivo dosimetry of patients who received IMRT. Hence, it is concluded that OSLDs can serve as effective dosimeters for in vivo dosimetry.

To report a single-institution experience of intensity-modulated radiotherapy (IMRT) and RapidArc treatment plans for the patients treated with low grade mucoepidermoid carcinoma (MEC) of the salivary gland while sparing the organs at risk (OARs) within tolerance limits.

Twenty-five patients with MEC were selected to develop and analyse the treatment plans using both of the techniques. Dose distributions were calculated using Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA). Plans were generated to deliver the dose of 6000 cGy in 30 fractions. For IMRT, seven angle plans were used and for RapidArc, two half arcs were used with the same 6 MV photon beam. Quality of treatment plans was evaluated by using parameters such as, coverage, conformity index (CI), homogeneity index (HI), gradient index (GI), unified dosimetry index (UDI), dose volume histogram, delivery time and OARs sparing for IMRT and RapidArc plans.

The analysis revealed that IMRT and RapidArc coverages are 0·90 and 0·94, respectively; CIs are 1·15 and 1·10, respectively; HIs are 1·12 and 1·07, respectively; GIs are 0·94 and 0·98, respectively. Average UDI values for RapidArc and IMRT are 1·09 and 1·11, respectively. Integral dose comparison shows better OAR sparing for RapidArc. RapidArc plans have the shorter beam on time (45%) in comparison with IMRT plans.

Planning constraints were achieved in both techniques. However, RapidArc showed better quality treatment plan, OARs sparing and shorter delivery time as compared to IMRT.

Radiotherapy is a mainstay of cancer therapy for a wide variety of anatomical areas. An unfortunate side effect of treatment can be radiation damage to the skin which can be a painful and debilitating problem. Previous experience from the experimental use of Flamigel® in two large-scale clinical studies on affected skin has proven sufficiently positive for the addition of a new product in the Flamigel® family (now commercially available in the UK as Flamigel RT®, Flen Health UK). The aim of this investigation is to evaluate the use of this new product to study how effective it is in the prevention and/or treatment of radiation-induced skin damage.

A survey was conducted among radiotherapy specialist teams in dedicated UK radiotherapy centres between 1 January 2017 and 31 October 2017. This report is of a preliminary evaluation conducted by UK-based specialists on 108 patients undergoing radiotherapy. The scoring system for skin reactions of the ‘Radiation Therapy Oncology Group’ was used.

Results show that the use of Flamigel® has the potential to soothe (p = 0·0001), reduce pain (p = 0·0001) and reduce pruritus (p = 0·004). The product met the expectations of the clinicians involved (p < 0·0001) of whom most were happy to continue use or to recommend its use to colleagues (p < 0·0001).

Flamigel® is an effective treatment in the management of radiation-induced skin reactions. Erythema was unchanged through the study period (p = 0·42). No adverse reactions were reported after the use of Flamigel from twice to six times a day.

Spatially fractionated Grid radiation therapy (SFGRT) in an effective technique for bulky and radio-sensitive tumours. SFGRT using a constructed block has been used to evaluate the photon and photo-neutron (PN) dose measurement in 18-MV photon beam energy.

A mounted Grid block on to a Varian Clinac 2100c linear accelerator was used to perform photon dosimetry. The percentage depth dose, in-plane and cross-plane beam profile and output factor was measured by ionization chamber in water. The PN contamination was measured after photon dosimetry using the combination of thermoluminescence dosimetry types 600 and 700, and Polycarbonate Film dosimeters on the surface and in the maximum depth dose (dmax) of solid water™ slabs.

The valley-to-peak ration for 6 and 18 MV photon beams obtained from the beam profiles was ~35 and 72%, respectively. Fast and thermal PN equivalent dose decreased in the Grid field compared to an open field (without Grid).

The Grid therapy dosimetry compared to the conventional radiotherapy (without the grid) the production of fast and thermal neutrons were reduced. Using of a Grid block in high-energy photon beams for a long period of the treatment continuously might be a new source of contamination due to the interaction of photon beam resulting the activation of the Grid block

To evaluate the information needs of radiotherapy patients and their families. To explore influential factors regarding information-seeking behaviours. To identify the preferred formats of information and the optimum time for radiotherapy patients to receive information. To assess the implications for clinical practice in satisfying patient information needs.

A Cumulative Index to Nursing and Allied Health Literature database search of literature was undertaken and publications screened for retrieval with 36 qualifying for inclusion in the evaluation.

There was inconclusive evidence exploring the impact that patient age, diagnosis, family background, and educational status had on the information-seeking behaviours and preferences of cancer patients. There is an agreement that there are positive and negative benefits of using different formats of information: verbal, written, virtual, and so on, and ultimately healthcare providers must utilise a combination of information formats to satisfy the information needs and preferences of individual patients. Inconsistent data were found on the optimum time to deliver cancer information to patients and professionals, and therapeutic radiographers should not assume that their information priorities are the same as those of their patients—every patient has unique and individually specific information needs.

The information needs of patients and families are dependent on individual circumstances, and priorities have a tendency to change during the cancer management journey, presenting huge challenges for therapeutic radiographers who are required to regularly reassess and satisfy the varying needs and preferences. More research is needed within the area of information needs and preferences for cancer patients receiving radiotherapy.

Inflammatory bowel disease (IBD) [i.e., Crohn’s disease (CD) and ulcerative colitis (UC)] has been considered a relative contraindication for radiation therapy (RT) to the abdomen or pelvis, potentially preventing patients with a diagnosis of IBD from receiving definitive therapy for their malignancy.

Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) conventions, a PubMed/MEDLINE literature search was conducted using the keywords RT, brachytherapy, inflammatory bowel disease, Crohn’s disease, ulcerative colitis and toxicity.

A total of 1,206 publications were screened with an addition of 8 studies identified through hand searching. Nineteen studies met the inclusion criteria for quantitative analysis. The total population across all studies was 497 patients, 50·5% having UC, 37% having CD and an additional 12·5% having unspecified IBD. Primary gastrointestinal malignancy (55%) followed by prostate cancer (40%) composed the bulk of the population. Acute and late grade 3 or greater gastrointestinal specific toxicity ranged from 0–23% to 0–13% respectively for those patients with IBD treated with RT to the abdomen or pelvis. In the literature reviewed, RT does not appear to increase fistula or stricture formation or IBD flares; however, one study did note RT to be a statistically significant risk factor for subsequent IBD flare on multivariate analysis.

A review of reported acute and late toxicities suggests that patients with IBD should still be considered for definitive radiotherapy. Patient characteristics including IBD distribution relative to the irradiated field, inflammatory activity at the time of radiation, overall disease severity and disease phenotype in the case of CD (fistulising versus stricturing versus inflammatory only) should be considered on an individual basis when evaluating potential patients. When possible, advanced techniques with strict organ at risk dose constraints should be employed to limit toxicity in this patient population.

The aim of this paper is to investigate the effectiveness of physical exercise in managing fatigue during radiotherapy for prostate cancer patients. It explores the impact of various physical exercise regimes and their role in the prevention and management of fatigue to help inform best practice.

A literature search was conducted on OVID Medline database with a follow-up search on google scholar to include relevant references found during the initial search. Relevant systematic reviews and randomised controlled trials (RCTs) arising from this search were reviewed.

There is evidence to support the notion that physical exercise in all its forms is an effective and safe intervention for fatigue management for prostate cancer patients undergoing radiotherapy. Although widely studied, there is limited evidence of fatigue management strategies being clearly implemented into current radiotherapy practice for patients with prostate cancer. This information is essential to enable therapeutic radiographers to educate prostate cancer patients regarding effective exercise strategies and ensure that fatigue is managed optimally.

Further research is required into the optimum physical exercise prescription to reduce radiation-induced fatigue, and standardised best practice guidelines should be developed nationally. A future move toward patient education into physical exercise and wellbeing should be a central component of the therapeutic radiographer role with specialist advice offered by review radiographers, empowering patients to become more physically active during treatment. Therapeutic radiographers have a unique opportunity to educate and promote physical exercise through a holistic wellbeing approach that aims to mitigate fatigue and improve quality of life.

Merkel cell carcinoma (MCC) is an aggressive cutaneous neuroendocrine tumour. Although surgical resection is a treatment choice, it often occurs in the head and neck and occurs mainly in the elderly, making surgery impossible. Radical radiation therapy may be an alternative to surgery in these patients. In addition, radiation treatment may be performed even after recurrence after surgery.

An 82-year-old MCC patient had cT2N0M0, stage IIA MCC on the left cheek that metastasised to lymph node 2 months after surgery. She was treated with radiation monotherapy with a hypofractionation schedule (39 Gy at 3 Gy per fraction).

The patient achieved complete remission after radiotherapy without severe toxicities.

Supine orientation is the standard treatment position for radiation therapy for head and neck cancer. Some patients, however, cannot tolerate this due to pooling of secretions and airway concerns, and theoretically, treatment would be better tolerated in a prone position. Here, we described the first prone treatment setup and delivery for a patient with head and neck cancer.

A 68-year-old male patient with inoperable locally advanced, T4aN0M0, squamous cell carcinoma of the maxillary sinus was simulated, planned, and treated in prone position due to sinus congestion.

Prone position was well tolerated by the patient, who then did not require daily anaesthesia for airway secretion management. The prone dosimetry demonstrated good target coverage and normal tissue sparing. His treatment setup was found to be reproducible throughout the course of therapy.

We successfully demonstrated the feasibility of prone treatment position for patients with head and neck cancer who are unable to tolerate supine position due to unmanageable secretions. Consideration should be given to prone treatment when designing both radiation therapy protocols and individual treatment plans.