Current evidence for moderate and ultra-hypofractionated radiation therapy in prostate cancer: a summary of the results from phase 3 randomised trials.

PROBLEM: A low α/ß ratio for prostate cancer (PCa) compared to surrounding normal tissue theoretically implies therapeutical advantages with hypofractionated treatment. Data from large randomised control trials (RCTs) comparing moderate hypofractionated (MHRT, 2.4-3.4 Gray/fraction (Gy/fx)) and ultra-hypofractionated (UHRT, >5 Gy/fx) with conventionally fractionated radiation therapy (CFRT, 1.8-2 Gy/fx) and the possible clinical implications have been reviewed. MATERIALS AND METHOD: We searched PubMed, Cochrane and Scopus for RCT comparing MHRT/UHRT with CFRT treatment of locally and/or locally advanced (N0M0) PCa. We found six RCTs, which compared different radiation therapy regimes. Tumour control and acute and late toxicities are reported. RESULTS: MHRT was non-inferior to CFRT for intermediate-risk PCa, non-inferior for low-risk PCa and not superior in terms of tumour control for high-risk PCa. Acute toxicity rates were increased compared to CFRT, especially an increase in acute gastrointestinal adverse effects was seen. Late toxicity related to MHRT seems to be comparable. UHRT was non-inferior in terms of tumour control in one RCT, with increased acute toxicity, but with comparable late toxicity. One trial, however, indicated increased late toxicity rates with UHRT. DISCUSSION AND CONCLUSION: MHRT delivers similar therapeutic outcomes compared to CFRT in terms of tumour control and late toxicity for intermediate-risk PCa patients. Slightly more acute transient toxicity could be tolerated in favour of a shorter treatment course. UHRT should be regarded as an optional treatment for patients with low- and intermediate-risk disease applied at experienced centres in concordance with international and national guidelines.

The Quandary of DNA-Based Treatment Assessment in De Novo Metastatic Prostate Cancer in the Era of Precision Oncology.

Guidelines for genetic testing have been established for multiple tumor types, frequently indicating the most confident molecularly targeted treatment options. However, considering the often-complex presentation of individual cancer patients, in addition to the combinatorial complexity and inherent uncertainties of molecular findings, deriving optimal treatment strategies frequently becomes very challenging. Here, we report a comprehensive analysis of a 68-year-old male with metastatic prostate cancer, encompassing pathology and MRI findings, transcriptomic results, and key genomics findings from whole-exome sequencing, both somatic aberrations and germline variants. We identify multiple somatic aberrations that are known to be enriched in prostate cancer, including a deletion of PTEN and a fusion transcript involving BRCA2. The gene expression patterns in the tumor biopsy were also strikingly similar to prostate tumor samples from TCGA. Furthermore, we detected multiple lines of evidence for homologous recombination repair deficiency (HRD), including a dominant contribution by mutational signature SBS3, which is specifically attributed to HRD. On the basis of the genomic and transcriptomic findings, and in light of the clinical case presentation, we discussed the personalized treatment options that exist for this patient and the various challenges that one faces in the process of translating high-throughput sequencing data towards treatment regimens.

Ablative Radiotherapy in Prostate Cancer: Stereotactic Body Radiotherapy and High Dose Rate Brachytherapy.

Prostate cancer (PCa) is the most common noncutaneous solid organ malignancy among men worldwide. Radiation therapy is a standard of care treatment option that has historically been delivered in the form of small daily doses of radiation over the span of multiple weeks. PCa appears to have a unique sensitivity to higher doses of radiation per fraction, rendering it susceptible to abbreviated forms of treatment. Stereotactic body radiation therapy (SBRT) and high-dose-rate brachytherapy (HDRBT) are both modern radiation modalities that allow the precise delivery of ablative doses of radiation to the prostate while maximally sparing sensitive surrounding normal structures. In this review, we highlight the evidence regarding the radiobiology, oncological outcomes, toxicity and dose/fractionation schemes of SBRT and HDRBT monotherapy in men with low-and intermediate-risk PCa.

Metastatic-directed therapy using PSMA-PET/CT at PSA relapse.

The side effects of androgen deprivation therapy (ADT) as general treatment against prostate cancer are known to impair quality of life. However, the optimal onset of ADT at PSA relapse is unknown, especially in patients with normal testosterone. In our case a limited PSMA avid lymph node was detected on PET/CT. Our case highlights the importance of metastasis-directed therapy balancing general versus tailored treatment in the decision making in the era of advanced molecular imaging. By using PSMA-PET/CT and radiation we were able to pinpoint the metastasis prolonging the ADT-free survival, thus sparing the patient the side-effects of continuous ADT.