Prostate cancer is the most commonly diagnosed cancer in men and it is responsible for about 10% of all cancer mortalities in both American and Canadian men. At present, serum prostate-specific antigen levels remain the most commonly used test to detect prostate cancer, and the standard and definitive diagnosis of the disease is via prostate biopsy. Conventional tissue biopsies are usually invasive, expensive, painful, time-consuming, and unsuitable for screening and need to be consistently evaluated by expert pathologists and have limited repeatability. Consequently, liquid biopsies are emerging as a favourable alternative to conventional tissue biopsies, providing a non-invasive and cost-effective approach for screening, diagnosis, treatment and monitoring of prostate cancer patients.

We searched several databases from August to December 2020 for relevant studies published in English between 2000 and 2020 and reporting on liquid-based biomarkers available in detectable quantities in patient bodily fluid samples. In this narrative review paper, we describe seven novel and promising liquid-based biomarkers that potentially account for individual patient variability as well as used in disease risk assessment, screening for early disease detection and diagnosis, identification of patients’ risk for metastatic disease and subsequent relapse, monitoring patient response to specific treatment and providing clinicians the potential to stratify patients likely to benefit from a particular treatment.

The concept of precision medicine from prevention to treatment techniques that take individual patient variability into account will depend on the development of effective clinical biomarkers that interrogate key aberrant pathways potentially targetable with molecular targets or immunologic therapies. Liquid-based biomarkers with high sensitivity and specificity for prostate cancer are emerging as minimally invasive, lower risk, readily obtainable and easily repeatable technique for screening for early disease detection and diagnosis, patient stratification at diagnosis into different risk categories, identification of patients’ risk for metastatic disease and subsequent relapse, and real-time monitoring of patient response to specific treatment. Thus, effective liquid-based biomarkers will potentially shift the treatment paradigm of prostate cancer towards more personalised and targeted medicine.

Pigmented villonodular synovitis (PVNS) is a rare benign proliferative disease of the synovium with locally aggressive behaviour. We reviewed our experience using external beam radiotherapy (RT) in the treatment of PVNS.

We report five cases of PVNS who underwent Arthroscopic Synovectomy followed by postoperative RT in National Oncology centre in Oman. The total dose RT ranges between 30 and 36 Gray (Gy) Three-dimensional radiotherapy technique.

Postoperative RT is effective in preventing disease recurrence and should be offered following maximal cytoreduction to enhance local control in PVNS.

Globally, cancer is the second leading cause of death, and it is estimated that over 18·1 million new cases are diagnosed annually. The COVID-19 pandemic has significantly impacted almost every aspect of the provision and management of cancer care worldwide. The time-critical nature of COVID-19 diagnosis and the large number of patients requiring hospitalisation necessitated the rerouting of already limited resources available for cancer services and programmes to the care of COVID-19 patients. Furthermore, the stringent social distancing, restricted in-hospital visits and lockdown measures instituted by various governments resulted in the disruption of the oncologic continuum including screening, diagnostic and prevention programmes, treatments and follow-up services as well as research and clinical trial programmes.

We searched several databases from October 2020 to January 2021 for relevant studies published in English between 2020 and 2021 and reporting on the impact of COVID-19 on the cancer care continuum. This narrative review paper describes the impact of the COVID-19 pandemic on the cancer patient care continuum from screening and prevention to treatments and ongoing management of patients.

The COVID-19 pandemic has profoundly impacted cancer care and the management of cancer services and patients. Nevertheless, the oncology healthcare communities worldwide have done phenomenal work with joint and collaborative efforts, utilising best available evidence-based guidelines to continue to give safe and effective treatments for cancer patients while maintaining the safety of patients, healthcare professionals and the general population. Nevertheless, several healthcare centres are now faced with significant challenges with the management of the backlog of screening, diagnosis and treatment cases. It is imperative that governments, leaders of healthcare centres and healthcare professionals take all necessary actions and policies focused on minimising further system-level delays to cancer screening, diagnosis, treatment initiation and clearing of all backlogs cases from the COVID-19 pandemic in order to mitigate the negative impact on cancer outcomes.

The central nervous system (CNS) embryonal tumour is a rare malignancy reported in adults and more commonly in children. The most available treatments may cause neurological dysfunctions requiring clinical attention.

A 29-year-old male was referred with ataxia and diplopia, and brain imaging revealed a posterior fossa lesion suggesting medulloblastoma. The tumour and related symptoms were notably alleviated following treatment with dexamethasone. Following the recurrence of tumour, a biopsy and pathology report, the diagnosis of desmoplastic/nodular medulloblastoma was confirmed. The patient underwent 18 fractions of 180 cGy spine and whole-brain radiation therapy (RT). In addition, 5400 cGy irradiation in 12 fractions was given to the posterior fossa together with 2 mg/m2 intravenous vincristine (VCR) weekly over 6 weeks. Following a 3-week break, the patient was scheduled to receive 150 mg/m2/day temozolomide for 5 days, 2 mg VCR and 65 mg/m2/day cisplatin every 3 weeks for 8 cycles.

The patient gained survival benefit to date (60 months since diagnosis) with favourable life quality. The promising response in this one exemplary case study proposes that a combined chemotherapy regimen including temozolomide, vincristine and cisplatin is an effective treatment choice for CNS embryonal tumours following RT; however, the further evaluation and a randomised clinical trial are needed.

Centrally located early-stage non-small cell lung cancer in patients who are unfit for surgery are treated with fractionated radiotherapy. We present the outcomes of a moderately hypofractionated accelerated dose regimen of 50 Gy in 15 fractions from a single centre in the UK.

Electronic case notes and radiotherapy records of lung cancer patients treated between January 2014 and December 2016 were retrospectively reviewed. Adult Comorbidity Evaluation-27 score was used to evaluate comorbidities. Mean lung doses and percentage of lung receiving more than 20 Gy were calculated for all patients. Survival outcomes were estimated using Kaplan–Meier curves.

Fifty-three patients were included in the study; the median follow-up was 20.2 months. 87% of patients had stage I disease. There was no 30-day post-treatment mortality. Ninety-day mortality rate after radiotherapy was 3.8%. Grade 2 pneumonitis was seen in five patients while no grade 3 or 4 pneumonitis was observed. The median progression-free survival (PFS) and overall survival (OS) were 18.5 months and 28.2 months, respectively. The estimated 1 and 2 years PFS were 62.3% and 41.3%, respectively, and OS were 77.4% and 56.6%, respectively. Worsening performance status was associated with worse survival on cox regression analysis. Disease relapsed in 36% of patients. 7.5% of patients with relapsed disease had infield recurrence.

50 Gy in 15 fractions radiotherapy for central early-stage lung cancer is a feasible choice that requires further randomised trials.

To study the effect of deep inspiration breath hold (DIBH) on Fast-Forward trial for left-sided breast radiotherapy dosimetrically using tangential field-in-field (FiF), flattening filtered volumetric-modulated arc therapy (FF-VMAT) and flattening filter free volumetric-modulated arc therapy (FFF-VMAT) in comparison with free breathing (FB).

Computed tomography images were acquired on 15 patients with carcinoma of left breast in FB and DIBH. Planning target volume (PTV) and organs at risk were contoured on both image sets. Dose of 26 Gy in five daily fractions was prescribed to PTV. FiF, FF-VMAT and FFF-VMAT plans were created in treatment planning system on both FB and DIBH. PTV V95%, V107%, D0·1 cc, CI and HI, heart V1·5 Gy, V7 Gy, lung left V8 Gy, monitor units (MU) and beam ON time were used for evaluation. Different technique analysis in same breathing condition and FB versus DIBH for same planning technique were performed.

Mean of all 15 patients was reported as mean ± 1 standard deviation. PTV V95% was 97·55 ± 0·10 (FiF), 95·75 ± 0·66 (FF-VMAT) and 96·15 ± 0·46 (FFF-VMAT) in FB while 97·34 ± 0·50 (FiF), 96·03 ± 0·71 (FF-VMAT) and 95·86 ± 0·63 (FFF-VMAT) in DIBH. Heart V7 Gy was 8·53 ± 4·26 (FiF), 8·86 ± 2·20 (FF-VMAT) and 9·27 ± 2·46 (FFF-VMAT) in FB while 6·30 ± 2·98 (FiF), 5·23 ± 2·20 (FF-VMAT) and 4·68 ± 2·01 (FFF-VMAT) in DIBH. p-value of heart V7 Gy between FB and DIBH was 0·278 (FiF), 0·009 (FF-VMAT) and 0·003 (FFF-VMAT). Beam ON time for FFF-VMAT was reduced by 65% (FF-VMAT) and 11% (FiF).

Conformal dose to PTV was achieved better with VMAT plans. FFF-VMAT was delivered in less time compared to FF-VMAT and FiF for 26 Gy in five fractions. Heart dose can be significantly minimised with DIBH for VMAT plans.

To evaluate the prevalence and risk factors of arm lymphedema in patients with breast cancer.

Between 2006 and 2017, we investigated patients with breast cancer after breast surgery who received adjuvant radiotherapy at the breast or chest wall, and/or adjuvant radiotherapy at regional lymph nodes, and standard systemic chemotherapy depending on disease stage and risk factors. We assessed arm lymphedema using arm circumference measurement differences on the treated side compared with the opposite arm (≥2 cm measurements at any one position). Associations between arm lymphedema and potential risk factors were identified using statistical analysis.

In 308 patients, arm lymphedema prevalence was 6·2%. Patients having ≥20 lymph nodes removed (hazard ratio (HR) = 3·29; 95% confidence interval (CI): 1·12–8·87), undergoing regional lymph node irradiation (HR = 1·81; 95% CI: 1·09–13·28), and no arm and shoulder exercises after treatment (HR = 3·16; 95% CI: 1·89–5·26) had a higher risk of arm lymphedema.

Arm lymphedema is a serious breast cancer complication and is a preventable morbidity. Planning arm and shoulder exercises in line with adjuvant treatments and increasing clinical awareness of early indications could help lower the risk of occurrence.

To propose a new matching method for the supraclavicular (SC) and tangential fields on three-dimensional radiotherapy (3DRT) for postmastectomy radiotherapy (PMRT).

A method of matching coplanar field borders (CFB) between the tangential and SC fields was created in 3DRT. The collimator angle of the medial tangential field was calculated to coplanar the SC field. The proposed method performance was ultimately benchmarked using the half beam block (HBB) and traditional three-field monoisocenter (TTM) methods by dosimetric comparison. The decision score was then employed to clarify the performance among these methods.

The results show that the TTM method exhibited not only low doses on the organs at risk (OAR) but also on the matching fields. The CFB and HBB produced comparable results, but the ipsilateral lung yielded lesser amounts than the HBB. The decision score indicated a low performance level when using the TTM method, whereas the CBF method exhibited a slightly higher performance score than the HBB.

The CFB exhibited good performance in terms of the dose on OARs and at the matching fields. This method offers a comparable level of performance to the HBB. Thus, the CFB offers an alternative method of significant interest in PMRT.

To analyse the patterns of care and clinical outcomes of patients diagnosed with cervical cancer International Federation of Gynecology and Obstetrics (FIGO) stage IVA treated at a tertiary care centre in South India.

The electronic medical records of 2,476 patients diagnosed with cervical cancer at a tertiary care institution between January 2005 and December 2018 were reviewed. Among them, 96 patients diagnosed with histologically proven carcinoma cervix stage IVA established by either cystoscopy or proctoscopy were included. Four patients who did not receive treatment at the study centre were excluded and 92 patients were available for final analysis.

The median follow-up period was 12 months (2–131 months). Of the 92 patients, 59 patients (64·13%) received radiation therapy (RT) alone, 22 patients (23·9%) received chemoradiation (CRT), three patients (3·26%) received neoadjuvant chemotherapy (NACT) followed by RT, one (1·08%) received NACT followed by CRT, four patients (4·35%) received chemotherapy alone, while three (3·26%) were offered best supportive care. The median progression-free survival (PFS) was 12 months (95% CI: 9·6–14·4 months) and median overall survival (OS) was 25 months (95% CI: 16·6–33·4 months). The 2-year and 3-year PFS was 30 and 20%, respectively, and the OS was 50 and 32%, respectively.

The management of stage IVA cervical cancer needs to be individualised to achieve a fine balance between local control, toxicity, and quality of life. RT is the mainstay of treatment with concurrent chemotherapy in carefully selected patients. Involvement of palliative care team early in the course of treatment adds a holistic approach to the continuum of oncological care.

There are only limited studies available in literature that discuss methods to reduce the oesophageal dose and acute oesophagitis during breast cancer radiotherapy. The aim of this study is to compare dose volumetric parameters of oesophagus in radiation treatment of breast with and without oesophagus delineation.

Treatment plans of 44 patients, who underwent chest wall and supraclavicular fossa irradiation, were selected for the study. Oesophagus was later delineated and treatment replanned using three-dimensional conformal radiotherapy (3DCRT) considering oesophagus as an organ at risk (OAR). The dose prescribed was 40 Gy/15 fractions to the planning target volume (PTV). Dose volumetric parameters of oesophagus such as maximum dose (Dmax), mean dose (Dmean), the percentage of oesophagus volume receiving ≥15Gy (V15), ≥25Gy(V25), ≥33Gy(V33) and ipsilateral lung volume parameters V4, V8 and V16 were compared with already executed plans in which oesophagus was not delineated.

Contouring the oesophagus as an OAR as a part of the radiotherapy treatment for Carcinoma Breast resulted in statistically significant reduction in dose to the oesophagus. No statistically significant change was found in the ipsilateral lung volume parameters. No compromise in plan quality was required as evident from the statistically non-significant differences in Homogeneity index and Conformity index.

3DCRT planning with oesophagus delineation can be considered as a method to reduce oesophageal dose and the acute oesophageal toxicity during radiotherapy for carcinoma breast.

The dosimetric and clinical advantages offered by implementation of pencil beam scanning (PBS) proton therapy for moving thoracic tumours is hindered by interplay effect. The purpose of this study is to evaluate the impact of large proton beam spot size along with adaptive aperture (AA) and various motion mitigation techniques on the interplay effect for a range of motion amplitudes in a three-dimensional (3D) respiratory motion phantom.

Point doses using ionisation chamber (IC) and planner dose distributions with radiochromic film were compared against the corresponding treatment planning system (TPS) information. A 3D respiratory motion phantom was scanned either for static or 4D computed tomographic (CT) technique for 6-, 10- and 14-mm motion amplitudes in SI direction. For free breathing (FB) treatment, a tumour was contoured on maximum intensity projection scan and an average scan was used for treatment planning. Each FB treatment was delivered with one, three and five volumetric repaintings (VRs). Three phases (CT40–60%) were extracted from the 4D-CT scans of each motion amplitude for the respiratory-gated treatment and were used for the treatment planning and delivery. All treatment plans were made using AA and robustly optimised with 5-mm set-up and 3·5% density uncertainty. A total of 26 treatment plans were delivered to IC and film using static, dynamic and respiratory-gated treatments combinations. A percent dose difference between IC and TPS for the point dose and gamma indices for film–TPS planner dose comparison was used.

The dose profile of film and TPS for the static phantom matched well, and percent dose difference between IC and TPS was 0·4%. The percent dose difference for all the gated treatments were below 3·0% except 14-mm motion amplitude-gated treatment. The gamma passing rate was more than 95% for film–TPS comparison for all gated treatment for the investigated gamma acceptance criteria. For FB treatments, the percent dose difference for 6-, 10- and 14-mm motion amplitude was 1·4%, −2·7% and −4·1%, respectively. As the number of VR increased, the percent difference between measured and calculated values decreased. The gamma passing rate met the required tolerance for different acceptance criteria except for the 14-mm motion amplitude FB treatment.

The PBS technique for the FB thoracic treatments up to 10-mm motion amplitude can be implemented with an acceptable accuracy using large proton beam spot size, AA and robust optimisation. The impact of the interplay effect can be reduced with VR and respiratory-gated treatment and extend the treatable tumour motion amplitude.

Optimal preoperative therapy regimen in the treatment of resectable retroperitoneal sarcoma (RPS) remains unclear. This study compares the impact of preoperative radiation, chemoradiation and chemotherapy on overall survival (OS) in RPS patients.

The National Cancer Database (NCDB) was queried for patients with non-metastatic, resectable RPS (2006–15). The primary endpoint was OS, evaluated by Kaplan–Meier method, log-rank test, Cox multivariable analysis and propensity score matching.

A total of 1,253 patients met the inclusion criteria, with 210 patients (17%) receiving chemoradiation, 850 patients (68%) receiving radiation and 193 patients (15%) receiving chemotherapy. On Cox multivariable analysis, when compared to preoperative chemoradiation, preoperative radiation was not associated with improved OS (hazards ratio [HR] 0·98, 95% CI 0·76–1·25, p = 0·84), while preoperative chemotherapy was associated with worse OS (HR 1·64, 95% CI 1·24–2·18, p < 0·001). Similar findings were observed in 199 and 128 matched pairs for preoperative radiation and chemotherapy, respectively, when compared to preoperative chemoradiation.

Our study suggested an OS benefit in using preoperative chemoradiation compared to chemotherapy alone, but OS outcomes were comparable between preoperative chemoradiation and radiation alone.

Radiotherapy to the head and neck region may cause considerable radiotherapy-induced changes in the surrounding tissues. These changes are oral mucositis, hyposalivation, dental caries, osteoradionecrosis, trismus and overall impact on patients’ quality of life. Tooth-coloured synthetic materials, unlike metallic restoration, did not influence radiation dose distribution. However, their exposure to a gamma radiation therapeutic dose during treatment might cause structural and compositional changes that alter their mechanical and physical properties.

This study intends to evaluate the effect of Co 60 gamma rays on shear bond strength and marginal adaptation of already restored tooth surfaces, to help in material selection before the onset of radiotherapy.

Hundred freshly extracted human permanent mandibular molar teeth collected and stored in a 0·2% thymol solution for disinfection and were randomly divided into two groups of 50 each, to be tested for the shear bond strength of restoration to dentin and the marginal gap at tooth–restoration interface, respectively.

ANOVA showed a significant effect of both radiotherapy (F = 40·33, p < 0·001) and restorations (134·00, p < 0·001) on the marginal gap at the interface. In the without radiotherapy group, the mean marginal gap was least in Group Z250, and in with radiation, Bulk Fill has the least mean marginal gap. The mean shear bond strength was comparatively higher for all restorations without radiation than with radiation (p < 0·001).

Gamma radiation affects the physical or mechanical properties of tooth structure and the tooth restorative interface. Composites seem to be good restorative material when placed before the onset of radiotherapy in head and neck cancer patients.

Adrenocortical carcinoma (ACC) is a rare and aggressive malignancy. Surgery is the mainstay of treatment, still even after a R0 surgical margins, there is a high risk of recurrence.

A 26-year-old female diagnosed with a large functioning ACC treated with a trimodality approach (surgery, radiotherapy and chemotherapy). Postoperative radiotherapy was proposed regarding the high risk of recurrence. A dose of 50.4 Gy in 28 fractions was delivered to the patient using a volumetric-modulated arc therapy plan. Radiotherapy was safe and well tolerated, and no local recurrence was observed so far (13 months after radiotherapy).

Due to the rarity of ACC and the lack of evidence regarding this entity, therapeutic approach can be challenging. Recent evidence suggests that radiotherapy could have an important role in the therapeutic arsenal.

The aim of this service review was to review whether implementing a formal training package increased therapeutic radiographer confidence and competence in recognising neutropenic sepsis in radiotherapy patients. In addition, authors also investigated whether the introduction of a weekly National Early Warning Score (NEWS) protocol had been successful in identifying cases of neutropenic sepsis.

Therapeutic radiographer (n = 13) views on the new protocol were collected through an online questionnaire. A review of the clinical observation sheets of patients who received chemo-radiotherapy (n = 49) between 18 April 2019 and 31 October 2019 was undertaken. Information on disease site, NEWS scores, number of patients who had become neutropenic and action taken by therapeutic radiographers was collected.

The majority of respondents to the questionnaire found that training benefitted both professionals and patients. Some challenges were highlighted relating to increased workload. For patients receiving regular observations, NEWS scores ranged from 0 to 4. When a patient scored on NEWS, the most common score was 1 across all treatment sites except cervix.

Implementing a neutropenic sepsis protocol appears to be beneficial to therapeutic radiographers as professionals, increasing their confidence in patient assessment and monitoring. Regular observations may help to identify deteriorating patients alongside clinical judgement and symptom reviews.

Few studies claimed that dynamic jaw (DJ) mode in Helical TomoTherapy® (HT) could improve the cranio-caudal dose distribution without prolonging the treatment time in treating different types of cancer. Also, studies suggested that DJ with a wider 5 cm field width (FW) could replace fixed jaws (FJ) with 2.5 cm FW to reduce the delivery time with the sustainable plan quality. Yet, the study on breast cancer with supraclavicular fossa (SCF) nodal involvement using DJ mode in HT is limited. This study aims to evaluate the DJ mode retrospectively by comparing their dosimetric quality with normal tissue complication probability (NTCP) of organs at risk and treatment delivery time with FJ mode on treating left-side breast with SCF nodal involvement.

All post-mastectomy patients, who had been irradiated for left-side breast with SCF nodal involvement were selected retrospectively in this study. With the same dose constraint and prescription as the treated DJ2.5 plan, two extra plans using DJ mode with 5 cm FW(DJ5.0) and FJ mode with 2.5 cm FW (FJ2.5) were computed for plan comparison.

No statistical significance was found in all the parameters of PTV and OARs, except for V20 of whole lung. DJ5.0 received V20 in ipsilateral left lung than FJ2.5 and DJ2.5. However, the average delivery time of DJ5.0 was significantly lower than that of DJ2.5 and FJ2.5 by almost 40%.

No statistical significance was found in those dosimetric and radiobiological parameters among three modes while the delivery time has greatly reduced by using DJ5.0. A shorter treatment time can minimise intra-fractional error and better the patient’s experience during treatment.

This study aimed to evaluate the dosimetric effects of the metal prosthesis in radiotherapy by Siemens Primus 15 MV linac accelerator. In addition, it proposed the new material could lead to less dose perturbation.

The depth dose distributions of typical hip prostheses were calculated for 15 MV photons by MCNP-4C code. Five metal prostheses were selected to reveal the correlation between material type, density and dose perturbations of prostheses. Furthermore, the effects of the location and thickness of the prosthesis on the dose perturbation were also discussed and analysed.

The results showed that the Co-Cr-Mo alloy as the prosthesis had more influence on the dose at the interface of metal tissue. The dose increased at the entrance of this prosthesis and experienced the reduction when passed through it. Finally, the impact of the new PEEK biomedical polymer materials was also investigated, and the lowest dose perturbations were introduced based on the obtained results.

It was found that the mean relative dose before and after of PEEK prosthesis was 99·2 and 97·1%, respectively. Therefore, this new biomedical polymer material was proposed to replace the current metal implants.

This study aimed to investigate the uncertainty in organ delineation of low-dose computed tomography (CT) images using a high-strength iterative reconstruction (IR) during radiotherapy planning for the treatment of prostate cancer.

Two CT datasets were prepared with different dose levels by adjusting the reconstruction slice thickness. Two observers independently delineated the prostate, seminal vesicles, bladder and rectum on both images without referring to other modality images. The delineated organ volumes were compared between both images. Observer delineation variability was assessed using Dice similarity coefficient (DSC) and mean distance to agreement.

No significant differences regarding the delineated organ volumes were observed between the low- and standard-dose images for all organs. Regarding inter-observer variability, the DSC was relatively high for both images, whereas mean distance to agreement was not significantly different between images (p > 0·05 for all). Intra-observer variability for each observer showed high DSC (>0·8 and >0·9 for seminal vesicles and other organs, respectively) but no significant differences in the mean distance to agreement (p > 0·05 for all).

Our results indicate that low-dose CT images with high-strength IR would be available for organ delineation in the radiotherapy treatment planning for prostate cancer.

Variation in delineation of target volumes/organs at risk (OARs) is well recognised in radiotherapy and may be reduced by several methods including teaching. We evaluated the impact of teaching on contouring variation for thoracic/pelvic stereotactic ablative radiotherapy (SABR) during a virtual contouring workshop.

Target volume/OAR contours produced by workshop participants for three cases were evaluated against reference contours using DICE similarity coefficient (DSC) and line domain error (LDE) metrics. Pre- and post-workshop DSC results were compared using Wilcoxon signed ranks test to determine the impact of teaching during the workshop.

Of 50 workshop participants, paired pre- and post-workshop contours were available for 21 (42%), 20 (40%) and 22 (44%) participants for primary lung cancer, pelvic bone metastasis and pelvic node metastasis cases, respectively. Statistically significant improvements post-workshop in median DSC and LDE results were observed for 6 (50%) and 7 (58%) of 12 structures, respectively, although the magnitude of DSC/LDE improvement was modest in most cases. An increase in median DSC post-workshop ≥0·05 was only observed for GTVbone, IGTVlung and SacralPlex, and reduction in median LDE > 1 mm was only observed for GTVbone, CTVbone and SacralPlex. Post-workshop, median DSC values were >0·7 for 75% of structures. For 92% of the structures, post-workshop contours were considered to be acceptable or within acceptable variation following review by the workshop faculty.

This study has demonstrated that virtual SABR contouring training is feasible and was associated with some improvements in contouring variation for multiple target volumes/OARs.

To evaluate comparative dosimetry of brachytherapy treatment planning between a volume-based plan by computed tomography (CT) and a point-based plan by transabdominal ultrasound (TAUS) in CT datasets for brachytherapy.

From 2019 to 2021, 59 different datasets of CT images were collected from 38 patients treated by intracavitary brachytherapy with tandem ovoid or tandem ring applicators. At that time, TAUS was performed to prevent uterine perforation and to evaluate topography of the cervix during application. In volume-based planning by CT, the target dose was used to keep the dose at 90% of high-risk clinical target volume (HR-CTV), to give a dose of at least 7Gy, while in the point-based plan by TAUS, the target dose was used to keep the minimum dose to eight cervix reference points (measured by TAUS), to give a dose of at least 7Gy. The doses to targets and organs at risk were evaluated and compared between volume-based planning by CT and the point-based plan by TAUS.

Of 59 fractions, a tandem ovoid applicator was used in 48 fractions (81·3%). In the volume-based plan by CT, the mean doses to HR-CTV(D90), intermediate-risk clinical target volume (IR-CTV)(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 7·0, 3·9, 4·9, 2·9 and 3·3 Gy, respectively, while in the point-based plan by TAUS, the mean doses to HR-CTV(D90), IR-CTV(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 8·2, 4·6, 5·9, 3·4 and 3·9 Gy, respectively. The percentages of mean dose differences between TAUS and CT of HR-CTV(D90), IR-CTV(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 17·7, 19·5, 20·5, 19·5, 21·3 and 19·8%, respectively. With the target dose to the point-based plan by TAUS (7 Gy to the cervix reference points), this was close to D98 of HR-CTV with a mean percentage of difference of 0·6%.

The point-based plan by TAUS showed higher values to targets and organs at risk than the volume-based plan by CT. With the point-based plan by TAUS, it was close to D98 of HR-CTV.