Technical Innovations and Patient Support in Radiation Oncology最新文献

Radiotherapy (RT) is one of the three pillars of cancer treatment (with surgery and systemic therapies) and has proven to be a cost–effective modality for curative and palliative treatment. In low and middle-income countries, access to RT treatment is limited posing many challenges to patients and caregivers. Many patients living in low and middle-income countries (LMICs) such as Malawi spend enormous sums of money to be treated abroad, through Government schemes, or, more commonly, go without treatment. This paper reviews the progress of the Malawi Government in establishing the first dedicated cancer treatment center with RT facilities at Kamuzu Central Hospital in Lilongwe. Malawi is expected to have a fully functional dedicated RT centre towards the end of 2024 equipped with one cobalt machine, two linear accelerators (LINAC), and a high dose rate (HDR) Brachytherapy unit. More cancer patients will have access to RT services locally, resulting in the Government saving on the foreign currency required to treat patients out of the country. While there has been great progress towards establishment of services in Malawi, careful and strategic planning is needed for the sustainability of required resources to avoid long-term disruption of treatments.

Background and purpose

The adoption of hypo-fractionated stereotactic body radiotherapy (SBRT) for treating prostate cancer has led to an increase in specialised techniques for monitoring prostate motion. The aim of this study was to comprehensively review a radiation therapist (RTT) led treatment process in which two such systems were utilised, and present initial findings on their use within a SBRT prostate clinical trial.

Materials and Methods

18 patients were investigated, nine were fitted with the Micropos RayPilot^TM (RP) system (Micropos Medical, Gothenburg, SE) and nine were fitted with the Micropos Raypilot Hypocath ^TM (HC) system. 36.25 Gray (Gy) was delivered in 5 fractions over 7 days with daily pre- and post-treatment cone beam computed tomography (CBCT) images acquired. Acute toxicity was reported on completion of treatment at six- and 12-weeks post-treatment, using the Radiation Therapy Oncology Group (RTOG) grading system and vertical (Vrt), longitudinal (Lng) and lateral (Lat) transmitter displacements recorded.

Results

A significant difference was found in the Lat displacement between devices (P=0.003). A more consistent bladder volume was reported in the HC group (68.03 cc to 483.7 cc RP, 196.11 cc to 313.85 cc HC). No significant difference was observed in mean dose to the bladder, rectum and bladder dose maximum between the groups. Comparison of the rectal dose maximum between the groups reported a significant result (P=0.09). Comparing displacements with toxicity endpoints identified two significant correlations: Grade 2 Genitourinary (GU) at 6 weeks, P=0.029; and no toxicity, Gastrointestinal (GI) at 12 weeks P=0.013.

Conclusion

Both the directly implanted RP device and the urinary catheter-based HC device are capable of real time motion monitoring. Here, the HC system was advantageous in the SBRT prostate workflow.

Background and aims

Proton therapy (PRT) for Head Neck Cancer (HNC), in view of the Bragg peak, spares critical structures like oral mucosa better than IMRT. In PRT, mouth-bites, besides immobilising and separating mucosal surfaces, may also negate the end-of-range effect. We retrospectively analysed the details and dosimetric impact of mouth-bites in PRT for HNC.

Materials and methods

The data of consecutive HNC patients treated with IMPT from May 2020 to August 2022 were studied retrospectively. Details of the mouth-bite used, compliance and resultant mucosal separation were noted. Further analysis, restricted to previously unirradiated patients, comprised volumetric dosimetric data pertaining to the mouth-bite and distal mucosal surfaces. High LET zones, corresponding to 6–12 keV/micron, for mouth-bite doses above 30 Gy, were recalculated from existing plans.

Results

A mouth-bite was used in 69 of 80 consecutively treated patients, ranging from 8 to 42 mm in thickness, and 12 to 52 mm in the resultant mucosal sparing. In 42 patients in whom the mouth-bite V 32 Gy was > 0, median Dmean, absolute V32, V39, V50 and V60 GyE (Gray Equivalent) of the mouth bite was 35.65 GyE (Range: 2.65 – 60 GyE), 10 cc (Range: 0.1 – 32 cc), 7.6 cc (Range: 0.1 – 30.8 cc), 5.7 cc (Range: 0.2 – 29.2 cc) and 1.45 cc (Range: 0.2 – 18.1 cc) respectively, all significantly more than the spared adjacent mucosal surface. In absence of a mouth-bite, the spared mucosa would have at least partially received the high dose received by the mouth-bite. High LET zones were noted in 12 of 48 mouth-bites.

Conclusion

In PRT for HNC, mouth-bites play a vital role in improving the sparing of mucosa outside the target.

Background

Gastric cancer has a high prevalence in Asia and may only be diagnosed in advanced stages. Therefore, patients with gastric cancer may experience fatal symptoms, such as bleeding or stenosis at the time of consultation. In this review, we aimed to describe the effectiveness and toxicity of hemostatic radiotherapy (RT).

Methods

A total of 17 retrospective and 3 prospective studies were analyzed. The prescription dose, biologically effective dose, equivalent dose in 2 Gy fractions, response rate, survival prognosis, and toxicities were also reported.

Results

Using 20 studies, the following observations were made the hemostatic effect was ∼ 80 %, the mean survival time after irradiation was about 3 months, and prescribed doses of 30 Gy/10 fractions and 20 Gy/5 fractions were considered suitable.

Conclusion

In this review, studies on hemostatic irradiation have been summarized, and the most optimal treatment method has been proposed. 30 Gy/10 fractions and 20 Gy/5 fractions were ideal. However, because palliative RT is preferably completed within a short period of time, a randomized trial is needed to determine whether the 8 Gy/single fraction treatment is equivalent to fractionated RT. Therefore, more prospective studies are warranted to establish a standard of care for palliative RT in gastric cancer.

In the changing global landscape, education programs for radiation therapists (RTTs), also known as therapeutic radiographers or radiation therapy technologists, at higher education institutions (HEIs) are non-existent in many African countries. In countries with local RTT education programs, there is evidence of a wide variety of qualification types, including in-house training, diploma and degree offerings. However, what is consistent is the integrated curriculum approach to classroom theory and clinical work-based learning that across the continent follows the general structure of a work-integrated learning (WIL) approach, to enhance clinical competence and meet the needs of the health sector. This study used a qualitative approach with thematic analysis of publicly available documents and reflective writings followed by further analysis through application of the Cultural Historical Activity Theory (CHAT) to explore the changing landscape of oncology in Africa and the impact of this on the education of RTTs. The study was guided by the reflective research question: How can the systemic understanding of RTT training in a changing landscape enable competent and caring practice? The study extends prior research on RTT education in Africa and contributes to debates on the changing role of RTTs in a rapidly changing environment.

Introduction

At our department we have a dedicated 1.5 Tesla MRI/HDR brachytherapy suite, which provides the possibility of repeated MRI scanning before, during and after applicator insertion and before and/or after irradiation for patients with advanced cervical cancer. In this study we analysed the effect of this adaptive workflow. We investigated the number of interventions, their impact on organ doses (OAR) and the respective dose differences between total prescribed and total delivered doses.

Materials and methods

Seventy patients with locally advanced cervical cancer FIGO2009 stages IB-IVA, treated from June 2016 till August 2020, were retrospectively analysed. The standard brachytherapy schedule consisted of two applicator insertions and delivery of three or four HDR fractions.

OARs were recontoured on the repeated MRI scans. The D_2cm3 dose difference between total prescribed and total delivered dose for bladder, rectum, sigmoid and bowel were calculated.

Results

In total 153 interventions were performed, 3 replacements of the applicator, 23 adaptations of needle positions, bladder filling was changed 74 times and repeated rectal degassing 53 times. The impact of the rectal interventions was on average −1.2 Gy EQD2₃. Dose differences between total delivered and total prescribed D_2cm3 for bladder, rectum, sigmoid and bowel were −0.6, 0.3, 2.2 and −0.6 Gy EQD2₃, respectively.

Conclusions

An MRI scanner integrated into the brachytherapy suite enables multiple interventions based on the scans before treatment planning and dose delivery. This allows for customized treatment according to the changing anatomy of the individual patient and a better estimation of the delivered dose.

Purpose

Material and Methods

Results

Conclusion

Purpose or Objective

The aim of this study was to explore the potential relationship between the time estimation and psychological distress in patients with solid tumors prior to starting radiotherapy.

Materials and Methods

In this multicenter study were included a total of 344 patients with solid tumors (197 with and 147 without metastatic disease). The time estimation was assessed by evaluating each subjects prospective estimation of how fast 1 min passed compared to the actual time. The median value (35sec) of subjective perception of time was used to group cases into two categories for experience of time. We used the National Comprehensive Cancer Network Distress Thermometer at the beginning of treatment to determine the levels of distress, where it measures distress on a scale from 0 to 10. Patients scoring 4 or above (73.5 %) were regarded as having high levels of distress.

Results

The time estimation distributions significantly changed according to the level of distress. ROC analysis revealed that at the optimal cut off value of time estimation, patients with low and high distress levels can be discriminated with an AUC = 0.80 (95 % CI: 0.75– 0.85, p < 0.001) and with a sensitivity of 77.8 % and specificity of 73.3 %. In a multivariate logistic regression model, fast time estimation was an independent predictor of high levels of distress (OR 0.136; 95 % CI, 0.072–––0.256, p < 0.001).

Conclusion

Time estimation is a novel potent indicator of high levels of distress in cancer patients prior starting of radiotherapy.

Outcomes for patients receiving radiotherapy (RT) for non-metastatic esophageal cancer at a single institution were assessed, as well as the impact of factors including age and intensity modulated RT (IMRT) planning on patient outcomes. A retrospective cohort of patients treated with RT for stage I-III esophageal cancer between 2010 and 2018 was identified. Among 248 identified patients, 28 % identified as older (≥75 years of age). Other than histology, there were no other statistically significant differences in patient and tumour characteristics between the younger and older populations. Treatments varied between the two age groups, with significantly less older patients completing trimodality treatments (17 % vs 58 %). Median overall survival (M−OS) and progression-free survival (M−PFS) were 20 months and 12 months for all patients and 40 months and 26 months for trimodality patients, respectively. In the older patients, the M−OS improved from 13 months for all to 34 months for trimodality patients; and M−PFS from 10 months to 16 months. On multivariate analysis, the use of trimodality therapy showed improved OS (HR 0.26, p < 0.001). In the non-surgical older patient group, significantly better survival was seen in patients who had a heart V30Gy under 46 %. There was no significant difference in M−OS in patients planned with IMRT compared with 3D-conformal RT. Clinical outcomes in the treatment of esophageal cancer vary significantly by treatment approach, with the most favourable results in those receiving trimodality therapy. Among older patients deemed fit after assessment by the multidisciplinary team for trimodality treatments, the M−OS is comparable to the younger patient group.

Background

Physicians manage multiple obligations, providing best-practice treatment and patient- centred care in the standard treatment pathway while contributing to clinical trials simultaneously. These multifaceted responsibilities may introduce barriers and dilemmas to clinical trial execution, potentially impacting the clinical trial decision- making process. This study explores physicians’ barriers and dilemmas in executing clinical trials and the impact on clinical trial decision-making.

Method

Qualitative semi-structured interviews were conducted with experienced oncologists. Moreover, participant observations were performed during clinical encounters involving discussions about clinical trials. The analysis followed a structured approach: (1) transcription of data, (2) inductive text coding, (3) exploration of patterns, and (4) interpretation, leading to the results. The results were discussed and validated by the study participants.

Results

The results comprise (1) a description of the clinical practice, which presents the setting of clinical trial execution; (2) results regarding physicians’ barriers and dilemmas in executing clinical trials, leading to (3) the impact on clinical trial decision- making. The results involve barriers to time constraints for clinical trial tasks, dilemmas emerging from trial requirements or deviations from standard guidelines, and challenges with providing sufficient trial communication and adequate decision-making support, balancing between a paternalistic approach and respecting patient autonomy.

Conclusion

The demanding obligations of clinical practice constitute a complex setting for executing clinical trials, resulting in numerous barriers and dilemmas that impact the decision-making process in clinical trials. The study emphasises the need for tailored clinical trial decision-making interventions to facilitate supportive, informed, and non-directive clinical trial decision-making.