Future directions from past experience: a century of prostate radiotherapy

Radiomic Pipelines for Prostate Cancer in External Beam Radiation Therapy: A Review of Methods and Future Directions

Background: Prostate Cancer (PCa) is asymptomatic at an early stage and often painless, requiring only active surveillance. External Beam Radiotherapy (EBRT) is currently a curative option for localised and locally advanced diseases and a palliative option for metastatic low-volume disease. Although highly effective, especially in a hypofractionation scheme, 17.4% to 39.4% of all patients suffer from cancer recurrence after EBRT. But, radiographic findings also correlate with significant differences in protein expression patterns. In the PCa EBRT workflow, several imaging modalities are available for grading, staging and contouring. Using image data characterisation algorithms (radiomics), one can provide a quantitative analysis of prognostic and predictive treatment outcomes. Methods: This literature review searched for original studies in radiomics for PCa in the context of EBRT. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, this review includes 73 new studies and analyses datasets, imaging modality, segmentation technique, feature extraction, selection and model building methods. Results: Magnetic Resonance Imaging (MRI) is the preferred imaging modality for radiomic studies in PCa but Computed Tomography (CT), Positron Emission Tomography (PET) and Ultrasound (US) may offer valuable insights on tumour characterisation and treatment response prediction. Conclusions: Most radiomic studies used small, homogeneous and private datasets lacking external validation and variability. Future research should focus on collaborative efforts to create large, multicentric datasets and develop standardised methodologies, ensuring the full potential of radiomics in clinical practice.

Treatment of Localized and Locally Advanced, High-Risk Prostate Cancer: A Report From the First Prostate Cancer Consensus Conference for Developing Countries

PURPOSE

To generate and present survey results on important issues relevant to treatment and follow-up of localized and locally advanced, high-risk prostate cancer (PCa) focusing on developing countries.

METHODS

A panel of 99 PCa experts developed more than 300 survey questions of which 67 questions concern the main areas of interest of this article: treatment and follow-up of localized and locally advanced, high-risk PCa in developing countries. A larger panel of 99 international multidisciplinary cancer experts voted on these questions to create the recommendations for treatment and follow-up of localized and locally advanced, high-risk PCa in areas of limited resources discussed in this article.

RESULTS

The panel voted publicly but anonymously on the predefined questions. Each question was deemed consensus if 75% or more of the full panel had selected a particular answer. These answers are based on panelist opinion and not on a literature review or meta-analysis. For questions that refer to an area of limited resources, the recommendations considered cost-effectiveness as well as the possible therapies with easier and greater access. Each question had five to seven relevant answers including two nonanswers. Results were tabulated in real time.

CONCLUSION

The voting results and recommendations presented in this article can guide physicians managing localized and locally advanced, high-risk PCa in areas of limited resources. Individual clinical decision making should be supported by available data; however, as guidelines for treatment of localized and locally advanced, high-risk PCa in developing countries have not been defined, this article will serve as a point of reference when confronted with this disease.

Does the radiation approach affect acute toxicity in prostate cancer patients? A comparison of four radiation techniques

Introduction

Prostate cancer is treated with increasingly sophisticated radiation techniques. The aim of the study is to compare acute toxicity in patients managed with different therapeutic modalities.

Material and methods

A total of 60 patients irradiated between 2012 and 2016 were analyzed: A. conformal 3D - 11, B. intensity-modulated radiation therapy (IMRT) 20, C. image-guided radiation therapy (IGRT) - 19 and D. volumetric modulated arc therapy (VMAT) - 10. Patients' age ranged from 46 to 85 years (median 70.5), prostate-specific antigen values at the time of diagnosis were in the range of 3.54-154 ng/ml (median 15.9). Acute toxicity from the genitourinary (GU) and gastrointestinal (GI) tracts according to the European Organization for Research and Treatment of Cancer (EORTC) /Radiation Therapy Oncology Group (RTOG) grading system were assessed.

Results

All irradiation techniques were well tolerated and neither 3 nor 4 degrees acute toxicity was observed. Importantly, IGRT and IMRT did not lead to Grade 2 GI acute toxicity. There was no relationship between the severity of GU acute toxicity depending on the irradiation technique used (p = 0.8), but a trend towards a significant relationship was noted for GI acute toxicity (p = 0.05).

Conclusions

All assessed irradiation methods do not lead to severe acute adverse effects. Importantly, patients treated with IGRT and IMRT had only minor GI toxicity.

Evaluating the Impact of Post-Treatment Self-Management Guidelines for Prostate Cancer Survivors

BACKGROUND

With a rising number of prostate cancer survivors, transitioning patients to follow-up care has become more relevant in the current Albertan cancer care landscape and has led to a need for better patient education resources surrounding this topic. In response, the Alberta Provincial Genitourinary Tumour Team and Cancer Control Alberta have developed self-management guidelines to aid patients with prostate cancer during this transition. This study aimed to evaluate the effectiveness and impact of the new provincial self-management guidelines in facilitating transition from active curative external beam radiation treatment to primary community care.

METHODS

This prospective study used convenience sampling to recruit 18 patients with prostate cancer from two major cancer centers in Alberta: Calgary and Edmonton. Participants were given the self-management guidelines within their final week of external beam radiation treatment and a follow-up phone questionnaire 4 weeks later. Participants answered standardized questions regarding the self-management document based on the themes of timeliness, patient-centeredness, safety, effectiveness, and comprehensiveness.

RESULTS AND DISCUSSION

A thematic analysis of the results suggested that the majority of patients were satisfied with the document in all domains, but some expressed concern with the clarity of the document. They suggested improvements such as adding a side effect timeline, adding an appendix or symptom index, further simplifying the language, and coordinating delivery of the guidelines with an in-person education session.

CONCLUSION

Overall, our findings supported the effectiveness of the guidelines in providing self-management information. If implemented into practice, these guidelines could have a positive impact on the perception of patients with prostate cancer regarding transitioning to follow-up care.

The current state of randomized clinical trial evidence for prostate brachytherapy

Interstitial brachytherapy is one of several curative therapeutic options for the treatment of localized prostate cancer. In this review, we summarize all available randomized data to support the optimal use of prostate brachytherapy. Evidence from completed randomized controlled trials is the focus of this review with a presentation also of important ongoing trials. Gaps in knowledge are identified where future investigation may be fruitful with intent to inspire well-designed prospective studies with standardized treatment that focuses on improving oncological outcomes, reducing morbidity, or maintaining quality of life.

Adipose-Derived Mesenchymal Stromal Cells Improve the Healing of Colonic Anastomoses Following High Dose of Irradiation Through Anti-Inflammatory and Angiogenic Processes

Cancer patients treated with radiotherapy (RT) could develop severe late side effects that affect their quality of life. Long-term bowel complications after RT are mainly characterized by a transmural fibrosis that could lead to intestinal obstruction. Today, surgical resection is the only effective treatment. However, preoperative RT increases the risk of anastomotic leakage. In this study, we attempted to use mesenchymal stromal cells from adipose tissue (Ad-MSCs) to improve colonic anastomosis after high-dose irradiation. MSCs were isolated from the subcutaneous fat of rats, amplified in vitro, and characterized by flow cytometry. An animal model of late radiation side effects was induced by local irradiation of the colon. Colonic anastomosis was performed 4 wk after irradiation. It was analyzed another 4 wk later (i.e., 8 wk after irradiation). The Ad-MSC-treated group received injections several times before and after the surgical procedure. The therapeutic benefit of the Ad-MSC treatment was determined by colonoscopy and histology. The inflammatory process was investigated using Fluorine-182-Fluoro-2-Deoxy-d-Glucose Positron Emission Tomography and Computed Tomography (¹⁸F-FDG-PET/CT) imaging and macrophage infiltrate analyses. Vascular density was assessed using immunohistochemistry. Results show that Ad-MSC treatment reduces ulcer size, increases mucosal vascular density, and limits hemorrhage. We also determined that 1 Ad-MSC injection limits the inflammatory process, as evaluated through ¹⁸F-FDG-PET-CT (at 4 wk), with a greater proportion of type 2 macrophages after iterative cell injections (8 wk). In conclusion, Ad-MSC injections promote anastomotic healing in an irradiated colon through enhanced vessel formation and reduced inflammation. This study also determined parameters that could be improved in further investigations.

Focal Ablation of Prostate Cancer

The challenge to the urology community is to reduce the risks of screening and treatment by reducing the number of men undergoing unnecessary biopsy and whole-gland curative treatment of low-risk disease. There is compelling evidence that focal ablation of prostate cancer is truly minimally invasive and offers major functional advantages over whole-gland treatment.