Metastases-directed radiotherapy in castration resistant oligo metastatic prostate cancer: A multicentric retrospective study from the French group COLib

Oligometastases are defined as a number of detectable metastases less or equal to 5. In castrate-resistant oligo metastatic prostate Cancer (CR oligoM PC), Metastases-Directed Ablative radiotherapy (MDRT) is poorly investigated. Our study retrospectively reviewed the cases of CR oligoM PC treated with MDRT in 8 French high-volume radiotherapy centers. OS and PFS are defined as the delay between the first day of MDRT and death (OS) or progression according to PCWG criteria (PFS). OS and PFS are evaluated according to Kaplan Meyer, curves are compared with log rank test. Logistic regression was used to identify predictive factors for outcome: bone versus node metastasis, ISUP grade, PSA doubling Time (PSADT) at the time of MDRT, time to castration resistance. 107 patients were included in the study, among those 197 metastases received MDRT. For the overall population, the median follow-up was 25.2 months (1,4-145). OS was 93 % at 2 years and 81,4% at 3 years. At 2 years, 100 % of patients with node-only metastasis were alive versus 88,7% among those who have bone metastases (p = 0,72). The median PFS was 12,6 months (IC 95 % [9,6; 17]), with no difference among patients with node only disease versus the rest of the cohort. The PFS was 18,2 months (10,0; 32,4) in patients with PSADT >6 months versus 10,7 months (8,9; 14,3) when PSADT was inferior to 6 months. However, this difference did not reach significant. We did not find a correlation neither between ISUP grade (1-2 versus 3-4-5) and PFS, nor between hormone-sensitivity duration and PFS. Patients receiving MDRT for CR oligoM PC have a good prognosis with 81,6% OS at 3 years. PSA DT longer than 6 months could be related to better PFS. MDRT strategy could postpone the onset of new systemic treatment with median PFS >1 year.

Role of radiotherapy in the management of brain oligometastases

The management of patients with brain oligometastases is complex and relies on specific reasoning compared to extracranial oligometastases. The levels of evidence are still low because patients with brain oligometastases are frequently excluded from randomized clinical trials. Stereotactic radiotherapy should be preferred in this indication over whole brain irradiation, both for patients with metastases in place and for those who have undergone surgery. The decision of local treatment and its timing must be a multidisciplinary reflection taking into account the histological and molecular characteristics of the tumor as well as the intracranial efficacy of the prescribed systemic treatments. Great caution must be observed when using stereotactic radiotherapy and concomitant systemic treatments because interactions are still poorly documented. We present the recommendations of the French society of radiation oncology on the management of brain oligometastatic patients with radiotherapy.

Indication and perspectives of radiation therapy in the setting of de-novo metastatic prostate cancer

Prostate cancer is the most common cancer and the third leading cause of cancer mortality in men. Each year, approximately 10% of prostate cancers are diagnosed metastatic at initial presentation. The standard treatment option for de-novo metastatic prostate cancer is androgen deprivation therapy with novel hormonal agent or with chemotherapy. Recently, PEACE-1 trial highlighted the benefit of triplet therapy resulting in the combination of androgen deprivation therapy combined with docetaxel and abiraterone. Radiotherapy can be proposed in a curative intent or to treat local symptomatic disease. Nowadays, radiotherapy of the primary disease is only recommended for de novo low-burden/low-volume metastatic prostate cancer, as defined in the CHAARTED criteria. However, studies on stereotactic radiotherapy on oligometastases have shown that this therapeutic approach is feasible and well tolerated. Prospective research currently focuses on the benefit of intensification by combining treatment of the metastatic sites and the primary all together. The contribution of metabolic imaging to better define the target volumes and specify the oligometastatic character allows a better selection of patients. This article aims to define indications of radiotherapy and perspectives of this therapeutic option for de-novo metastatic prostate cancer.

The role of radiation therapy for de novo metastatic bladder and renal cancers

Metastatic bladder and renal cancers account respectively for 2.1% and 1.8% of cancer deaths worldwide. The advent of immune checkpoint inhibitors has revolutionized the management of metastatic disease, by demonstrating considerable improvements in overall survival. However, despite initial sensitivity to immune checkpoint inhibitors for most patients, both bladder and renal cancer are associated with short progression-free survival and overall survival, raising the need for further strategies to improve their efficacy. Combining systemic therapies with local approaches is a longstanding concept in urological oncology, in clinical settings including both oligometastatic and polymetastatic disease. Radiation therapy has been increasingly studied with either cytoreductive, consolidative, ablative or immune boosting purposes, but the long-term impact of this strategy remains unclear. This review intends to address the impact of radiation therapy with either curative or palliative intent, for synchronous de novo metastatic bladder and renal cancers.

Recommendations for stereotactic body radiation therapy for spine and non-spine bone metastases. A GETUG (French society of urological radiation oncolgists) consensus using a national two-round modified Delphi survey

Background and purpose

The relevance of metastasis-directed stereotactic body radiation therapy (SBRT) remains to be demonstrated through phase III trials. Multiple SBRT procedures have been published potentially resulting in a disparity of practices. Therefore, the french society of urological radiation oncolgists (GETUG) recognized the need for joint expert consensus guidelines for metastasis-directed SBRT in order to standardize practice in trials carried out by the group.

Materials and methods

After a comprehensive literature review, 97 recommendation statements were created regarding planning and delivery of spine bone (SBM) and non-spine bone metastases (NSBM) SBRT. These statements were then submitted to a national online two-round modified Delphi survey among main GETUG investigators. Consensus was achieved if a statement received ≥ 75 % agreements, a trend to consensus being defined as 65-74 % agreements. Any statement without consensus at round one was re-submitted in round two.

Results

Twenty-one out of 29 (72.4%) surveyed experts responded to both rounds. Seventy-five statements achieved consensus at round one leaving 22 statements needing a revote of which 16 achieved consensus and 5 a trend to consensus. The final rate of consensus was 91/97 (93.8%). Statements with no consensus concerned patient selection (3/19), dose and fractionation (1/11), prescription and dose objectives (1/9) and organs at risk delineation (1/15). The voting resulted in the writing of step-by-step consensus guidelines.

Conclusion

Consensus guidelines for SBM and NSBM SBRT were agreed upon using a validated modified Delphi approach. These guidelines will be used as per-protocole recommendations in ongoing and further GETUG clinical trials.

[What do we need to deliver "online" adapted radiotherapy treatment plans?]

During the joint SFRO/SFPM session of the 2019 congress, a state of the art of adaptive radiotherapy announced a strong impact in our clinical practice, in particular with the availability of treatment devices coupled to an MRI system. Three years later, it seems relevant to take stock of adaptive radiotherapy in practice, and especially the "online" strategy because it is indeed more and more accessible with recent hardware and software developments, such as coupled accelerators to a three-dimensional imaging device and algorithms based on artificial intelligence. However, the deployment of this promising strategy is complex because it contracts the usual time scale and upsets the usual organizations. So what do we need to deliver adapted treatment plans with an "online" strategy?

[Clinical research in radiotherapy oncology in private sector: A reality with a possible future?]

Clinical research is one of the activities of medical practice, particularly in oncology including radiotherapy. It was developed in the public sector and then in the liberal sector, in compliance with regulatory institutions, resulting in a doubling of inclusions over the last decade. Setting up and developing clinical research in the liberal sector are major axes in terms of interests: improving the proposition of care, access to innovation, to keep patients, intellectual stimulation, encouraging recruitment, activity of scientific publications, financial valorisation, quality of visibility… An inventory on French national territory via the national union of iadiotherapists oncologists (SNRO) and the club of liberal oncologists (Colib) is reported in this article, as well as examples of structuring and organization.

[Intermediate-risk prostate cancer treated with exclusive external irradiation: Focus on anatomical sites of recurrence in two French trials]

PURPOSE

Retrospective description of anatomical sites of relapse based on (18F)-choline PET-CT, (68Ga)-prostatic specific-membrane antigen PET-CT, bone scan, and prostate magnetic resonance imaging (MRI) data.

MATERIALS AND METHODS

From two French prospective cohorts, patients treated with exclusive radiotherapy for an intermediate-risk cancer were identified during their follow-ups. They were included if they presented a rising of the prostate-specific antigen (PSA) associated with the realization of an imaging showing the sites of recurrences.

RESULTS

Two hundred and sixty-three patients were included. After a median follow-up of 76 months (interquartile range [IQR] 67-95), 65 patients had biochemical recurrence and positive imaging. The median nadir PSA was 0.6ng/mL and the median PSA at recurrence was 3.4ng/mL. A single lesion was found in 48% of cases, 2 to 4 lesions in 43% of cases and more than 4 lesions in 9% of cases. The sites of relapse identified were prostate (37/65), prostate only (19/65), seminal vesicles (9/65) Pelvic nodes (35/65), extrapelvic nodes (15/65) and bone (13/65).

CONCLUSIONS

The majority of relapses presented as a single lesion localized in the pelvis.

Radiation therapy for brain metastases

We present the update of the recommendations of the French society for radiation oncology on radiation therapy for the management of brain metastases. It has evolved in recent years and has become more complex. As the life expectancy of patients has increased and retreatments have become more frequent, side effects must be absolutely avoided. Cognitive side effects must in particular be prevented, and the most modern radiation therapy techniques must be used systematically. New prognostic classifications specific to the primary tumour of patients, advances in imaging and radiation therapy technology and new systemic therapeutic strategies, are making treatment more relevant. Stereotactic radiation therapy has supplanted whole-brain radiation therapy both for patients with metastases in place and for those who underwent surgery. Hippocampus protection is possible with intensity-modulated radiation therapy. Its relevance in terms of cognitive functioning should be more clearly demonstrated but the requirement for its use is constantly increasing. New targeted cancer treatment therapies based on the nature of the primitive have complicated the notion of the place and timing of radiation therapy and the discussion during multidisciplinary care meeting to indicate the best sequences is becoming a challenging issue as data on the interaction between treatments remain to be documented. In the end, although aimed at patients in the palliative phase, the management of brain metastases is one of the locations for which technical reflection is the most challenging and treatment become increasingly personalized.

[Salvage radiotherapy after prostatectomy - what do do in case of elevated post operative PSA or macroscopic relapse?]

The management of the postoperative biological relapse of prostate cancer is most often based on salvage radiotherapy (RT) and a variable duration of hormone therapy (HT) in addition. The indications for RT±HT become more consensual for the adjuvant postoperative situation or in the event of a rising PSA level after a period where an undetectable PSA level was achieved. On the other hand, in the event of detectable PSA immediately postoperatively or in the event of a biological recurrence with macroscopic relapse in the prostate bed seen on conventional imaging assessment, the treatment options are still being evaluated. This article will describe these 2 situations and their current management but also will come through assessments with the contribution of modern imaging and new treatment options in terms of RT dose and RT±HT combination.

[The role of radiotherapy to the primary tumor and metastases in patients with oligometastatic prostate cancer]

Oligometastatic prostate cancer is among the most studied oligometastatic cancers in the literature. However few prospective studies have assessed stereotactic body radiotherapy (SBRT) for prostate cancer oligometastases. Two randomised phase II trials show a progression-free survival benefit compared with observation. Prospective registry data show very good local control and low toxicity too. Inclusion in ongoing trials should be strongly encouraged to define the role of SBRT in addition to systemic therapy. Radiation therapy to the primary tumour has been studied in randomised trials and provides an overall survival benefit in patients with low metastatic burden. The benefit is inversely correlated with the number of bone lesions using conventional imaging, up to three metastases. Radiotherapy to the primary tumour is recommended by the learned societies for patients with low metastatic burden. Its role in combination with second generation anti androgen therapy needs to be clarified.

Postoperative radiotherapy in prostate cancer: Dose and volumes

Approximately thirty percent of patients experience biochemical recurrence after radical prostatectomy for prostate cancer. Early salvage radiotherapy has recently become a standard of care in this setting. The purpose of this review is first to summarize current knowledge in terms of dose to the prostate bed in light of the recent SAKK 09/10 randomized phase III trial results. The evidence on moderate hypofractionation will also be discussed whereas extreme hypofractionation remains highly investigational. Regarding target volumes, several different guidelines have been published to address the need for standardization of postoperative target delineation. The recent GFRU (Groupe Francophone de Radiothérapie Urologique) recommendations could represent an international consensus.

[Recent advances in high-risk prostate cancer surgery]

The management of high-risk prostate cancer has greatly evolved in recent years. Advances in imaging helps to better define the actual aggressiveness of the disease, to plan the surgical procedure, and to improve the prognostic evaluation of this high-risk of recurrence disease. The information obtained by MRI and by targeted biopsies improves management before surgery. Advances in nuclear medicine and generalization of PSMA-PET scans are beginning to improve the initial stage of diagnosis, thanks to a better detection of lymph node and distant metastases. The oncological interest of these new imaging techniques, which then influence the therapeutic plan, remains to be defined. The curative impact of an extensive lymph node dissection, as currently recommended, remains to be proved, and recently published randomized trials do not provide firm conclusions. The new hormone therapies pave the way for an intensification of perioperative systemic treatment, with a significant action on the tumor tissue, but an impact on survival, which remains to be defined in the context of ongoing randomized trials.

Patterns of practice of androgen deprivation therapy combined to radiotherapy in favorable and unfavorable intermediate risk prostate cancer. Results of The PROACT Survey from the French GETUG Radiation Oncology group

PURPOSE

The intermediate-risk (IR) prostate cancer (PCa) group is heterogeneous in terms of prognosis. For unfavorable or favorable IR PCa treated by radiotherapy, the optimal strategy remains to be defined. In routine practice, the physician's decision to propose hormonal therapy (HT) is controversial. The PROACT survey aimed to evaluate pattern and preferences of daily practice in France in this IR population.

MATERIALS AND METHODS

A web questionnaire was distributed to French radiotherapy members of 91 centers of the Groupe d'Etude des Tumeurs Uro-Genitales (GETUG). The questionnaire included four sections concerning: (i) the specialists who prescribe treatments and multidisciplinary decisions (MTD) validation; (ii) the definition of IR subsets of patients; (iii) radiotherapy parameters; (iv) the pattern of practice regarding cardiovascular (CV) and (iv) metabolic evaluation. A descriptive presentation of the results was used.

RESULTS

Among the 82 responses (90% of the centers), HT schedules and irradiation techniques were validated by specific board meetings in 54% and 45% of the centers, respectively. Three-fourths (76%) of the centers identified a subset of IR patients for a dedicated strategy. The majority of centers consider PSA>15 (77%) and/or Gleason 7 (4+3) (87%) for an unfavorable IR definition. Overall, 41% of the centers performed systematically a CV evaluation before HT prescription while 61% consider only CV history/status in defining the type of HT. LHRH agonists are more frequently prescribed in both favorable (70%) and unfavorable (98%) IR patients. Finally, weight (80%), metabolic profile (70%) and CV status (77%) of patients are considered for follow-up under HT.

CONCLUSION

To the best of our knowledge, this is the first survey on HT practice in IR PCa. The PROACT survey indicates that three-quarters of the respondents identify subsets of IR-patients in tailoring therapy. The CV status of the patient is considered in guiding the HT decision, its duration and type of drug.

[Stereotaxic radiotherapy of primary extracranial tumors]

Stereotactic radiotherapy is a fundamental change from the conventional fractionated radiotherapy and represents a new therapeutic indication. Stereotactic radiotherapy is now a standard of care for inoperable patients or patients who refuse surgery. The results are encouraging with local control and survival rates very high in selected populations. The rate of late toxicity remains acceptable. Good tolerability makes it appropriate even for elderly and frail patients. In these fragile patients or in certain specific clinical situations, different surgical, radiotherapy or interventional radiology attitudes can be discussed on a case-by-case basis. These situations are considered in this article for the pulmonary, hepatic and prostatic localizations.

[Treatment of primary disease for synchronous metastatic prostate cancer]

The management of early metastatic prostate cancer is based on systemic treatment by androgen deprivation therapy with or without chemotherapy or next-generation anti-androgen therapies. Local treatment of the prostate was initially used only to alleviate local symptoms. However, local radiotherapy of the prostate has been the subject of retrospective and prospective studies in patients with better prognostic factors, particularly in oligometastatic status. The results of these studies support that prostate radiotherapy can prolong the survival of patients with a low metastatic burden. This article states the biological bases, the main published and future published studies aimed to embed this strategy to optimize therapeutic management.

[Prophylactic nodal radiotherapy in prostate cancer]

The risk of lymph node invasion, in case of prostate cancer, increases with the clinical stage of the disease, the Gleason score of prostate biopsies and the value of PSA at diagnosis. Historically, beyond 15% risk of lymph node involvement, irradiation of the pelvic areas was performed with prostate radiotherapy (RT) to take into account the risk of occult lymph node metastasis in patients at risk, but the benefit of this therapeutic approach remains to be demonstrated. The data from surgical lymph node dissection seem to question the risk levels, the escalation of the dose on the prostate increases the survival without relapse, the contribution of image-guided radiotherapy, (IGRT) and modulation of intensity (IMRT), decreases the toxicity of pelvic RT. This article reviews the principles of prophylactic ganglion irradiation for prostate cancer and discusses its relevance, current uncertainties, and prospective trials.

[The radiation oncologist, one of the actors in the patient's path after cancer. Follow up after prostate cancer]

Prostate cancer is the most common cancer of men over 50 years old. Localized prostatic cancer treatment may be responsible of a decline of patient's quality of life. The main actors of treatment are now focused on minimizing functional consequences of treatments. The radiation oncologist has a central role in patient monitoring. The follow-up is codified by official recommendations of learned societies to enhance the post-cancer period. The main objective of this article is to review the recommendations for clinical and biological follow-up. An inventory of the functional consequences of the various treatments will be detailed, and particularly those caused by androgen deprivation therapy, with a review of precautions before implementation, adverse effects and their management, as well as monitoring recommendations. The analysis of quality of life after curative treatment and suggestions to improve monitoring will also be discussed.

[Optimizing local control of high-risk prostate cancers through multimodal treatments]

Prostate cancer is a sensitive adenocarcinoma, in more than 80 % of cases, to chemical castration, due to its hormone dependence. Locally advanced and/or high-risk cancer is defined based on clinical stage, initial PSA value or high Gleason score. Hormone therapy associated with radiation therapy is the standard of management and improves local control, reduces the risk of distant metastasis and improves specific and overall survival. Duration of hormone therapy, dose level of radiation therapy alone or associated with brachytherapy are controversial data in the literature. Radical prostatectomy surgery is a therapeutic option that must be performed with extensive lymph node dissection and is often part of a multimodal care sequence. The therapeutic choice, multidisciplinary, depends on the age and co-morbidity of the patient, the prognostic criteria of the pathology and the urinary function of the patient. Current research focuses on optimizing local and distant control of these aggressive forms and incorporates neo-adjuvant or adjuvant chemotherapy and also new hormone therapies.