The rationale behind the \"International Consensus Conference for Advanced Breast Cancer\" (ABC) is to standardize the treatment of patients with advanced or metastatic breast cancer worldwide using an evidence-based approach. The aim is also to ensure that patients in all countries receive adequate treatment based on current treatment recommendations and standards. The 7th International Consensus Conference on Advanced Breast Cancer (ABC7) took place from November 9 to 12, 2023 in Lisbon/Portugal. ABC7 focused on metastatic disease as well as on locally advanced and inflammatory breast cancer. Special topics included the treatment of oligometastatic patients, leptomeningeal disease, treatment of brain metastases, and pregnant women with ABC. As in previous years, patient advocates from all over the world participated in the consensus conference and were involved in decision making.

Advances in characterizing cancer biology and the growing availability of novel targeted agents and immune therapeutics have significantly changed the prognosis of many patients with metastatic disease. Palliative radiotherapy needs to adapt to these developments. In this study, we summarize the available evidence for stereotactic body radiotherapy (SBRT) in the treatment of spinal metastases.
A systematic review and meta-analysis was performed using PRISMA methodology, including publications from January 2005 to September 2021, with the exception of the randomized phase III trial RTOG-0631 which was added in April 2023. Re-irradiation was excluded. For meta-analysis, a random-effects model was used to pool the data. Heterogeneity was assessed with the I2-test, assuming substantial and considerable as I2 > 50 % and I2 > 75 %, respectively. A p-value < 0.05 was considered statistically significant.
A total of 69 studies assessing the outcomes of 7236 metastases in 5736 patients were analyzed. SBRT for spine metastases showed high efficacy, with a pooled overall pain response rate of 83 % (95 % confidence interval [CI] 68 %-94 %), pooled complete pain response of 36 % (95 % CI: 20 %-53 %), and 1-year local control rate of 94 % (95 % CI: 86 %-99 %), although with high levels of heterogeneity among studies (I2 = 93 %, I2 = 86 %, and 86 %, respectively). Furthermore, SBRT was safe, with a pooled vertebral fracture rate of 9 % (95 % CI: 4 %-16 %), pooled radiation induced myelopathy rate of 0 % (95 % CI 0-2 %), and pooled pain flare rate of 6 % (95 % CI: 3 %-17 %), although with mixed levels of heterogeneity among the studies (I2 = 92 %, I2 = 0 %, and 95 %, respectively). Only 1.7 % of vertebral fractures required surgical stabilization.
Spine SBRT is characterized by a favorable efficacy and safety profile, providing durable results for pain control and disease control, which is particularly relevant for oligometastatic patients.

Oligometastatic prostate cancer is a new and emerging treatment field with only few prospective randomized studies published so far. Despite the lack of strong level I evidence, metastasis-directed therapies (MDT) are widely used in clinical practice, mainly based on retrospective and small phase 2 studies and with a large difference across centers. Pending results of ongoing prospective randomized trials, there is a clear need for more consistent treatment indications and radiotherapy practices.
A European Society for Radiotherapy and Oncology (ESTRO) Guidelines Committee consisting of radiation oncologists\' experts in prostate cancer was asked to answer a dedicated questionnaire, including 41 questions on the main controversial issues with regard to oligometastatic prostate cancer.
The panel achieved consensus on patient selection and routine use of prostate-specific membrane antigen positron emission tomography (PSMA PET) imaging as preferred staging and restaging imaging. MDT strategies are recommended in the de novo oligometastatic, oligorecurrent and oligoprogressive disease setting for nodal, bone and visceral metastases. Radiation therapy doses, volumes and techniques were discussed and commented.
These recommendations have the purpose of providing standardization and consensus to optimize the radiotherapy treatment of oligometastatic prostate cancer until mature results of randomized trials are available.

UNASSIGNED: Local treatment for bone metastases is becoming increasingly complex. National guidelines traditionally focus only on radiation therapy (RT), leaving a gap in clinical decision support resources available to clinicians. The objective of this study was to reach expert consensus regarding multidisciplinary management of non-spine bone metastases, which would facilitate standardizing treatment within an academic-community partnership.
UNASSIGNED: A multidisciplinary panel of physicians treating metastatic disease across the Memorial Sloan Kettering (MSK) Cancer Alliance, including community-based partner sites, was convened. Clinical questions rated of high importance in the management of non-spine bone metastases were identified via survey. A literature review was conducted, and panel physicians drafted initial recommendation statements. Consensus was gathered on recommendation statements through a modified Delphi process from a full panel of 17 physicians from radiation oncology, orthopaedic surgery, medical oncology, interventional radiology, and anesthesia pain. Consensus was defined a priori as 75% of respondents indicating \"agree\" or \"strongly agree\" with the consensus statement. Strength of Recommendation Taxonomy was employed to assign evidence strength for each statement.
UNASSIGNED: Seventeen clinical questions were identified, of which 11 (65%) were selected for the consensus process. Consensus was reached for 16 of 17 answer statements (94%), of which 12 were approved after Round 1 and additional 4 approved after Round 2 of the modified Delphi voting process. Topics included indications for referral to surgery or interventional radiology, radiation fractionation and appropriate use of stereotactic approaches, and the handling of systemic therapies during radiation. Evidence strength was most commonly C (n = 7), followed by B (n = 5) and A (n = 3).
UNASSIGNED: Consensus among a multidisciplinary panel of community and academic physicians treating non-spine bone metastases was feasible. Recommendations will assist clinicians and potentially provide measures to reduce variation across diverse practice settings. Findings highlight areas for further research such as pathologic fracture risk estimation, pre-operative radiation, and percutaneous ablation.

Oligometastatic prostate cancer (OMPC) is a heterogeneous disease state that is imperfectly understood, and its clinical implications are unclear.
To determine the consensus of a Dutch multidisciplinary expert panel on biological aspects, treatment goals, and management of OMPC in daily clinical practice.
The study comprised a modified Delphi method including an explorative survey with various statements and questions, followed by a consensus meeting to discuss and determine the agreement with revised statements and related items. The panel consisted of 34 Dutch representatives from urology, medical and radiation oncology, radiology, nuclear medicine, and basic research.
Agreement was determined with statements (five-point scale). Consensus was defined as ≥75% panel agreement with a statement.
Consensus existed for 56% of statements. The panel agreed that OMPC comprises a limited metastatic spread in the hormone-sensitive setting, in both the synchronous and the metachronous presentation. Limited metastatic spread was believed to involve three to five metastases and a maximum of two organs. Prostate-specific membrane antigen positron emission tomography/computed tomography scan was currently perceived as the most accurate diagnostic imaging modality. Although there was a consensus that targeted treatment of all metastases in OMPC will delay further dissemination of the disease, opinions on specific treatment regimens were divided. Panel outcomes were limited by the lack of scientific evidence on OMPC.
A multidisciplinary panel reached a consensus that OMPC is a specific disease state requiring a tailored treatment approach. OMPC registries and clinical studies should focus on both the biology and the clinical parameters in relation to optimal treatment strategies in synchronous and metachronous OMPC.
A group of Dutch medical specialists agreed that prostate cancer patients having few metastases may benefit from a new therapeutic approach. Clinical studies need to determine which treatment is best for each specific situation.