Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium

Immunotherapy-Boosted Stereotactic Ablative Radiotherapy in Inoperable Early-Stage Non-Small Cell Lung Cancer

OPINION STATEMENT

The combination of stereotactic ablative radiotherapy (SABR) with immune checkpoint inhibitors, known as iSABR, marks a significant evolution in treating early-stage, inoperable non-small cell lung cancer (NSCLC). Managing these cases requires a multidisciplinary approach involving radiation and medical oncologists. Clinical evidence from a meta-analysis of seven studies, including 462 patients, indicates that iSABR may offer better outcomes than SABR alone. The analysis showed significantly improved progression-free survival (PFS) rates at 1-, 2-, and 3-year follow-ups for iSABR compared to SABR. There was also a trend toward better overall survival (OS) with iSABR. Subgroup analyses highlighted enhanced 3-year PFS with programmed death-1 (PD-1) inhibitors and doses per fraction ≥ 12.5 Gy. While iSABR slightly increased the risk of grade ≥ 3 adverse events like pneumonitis, fatigue, and skin reactions, these risks are generally manageable within a multidisciplinary treatment framework. In conclusion, iSABR demonstrates potential benefits and manageable risks in phase I/II trials for early-stage, inoperable NSCLC, with improved PFS and acceptable toxicity. These findings warrant further investigation in a larger phase III prospective randomized controlled trial to validate efficacy, optimize protocols, and establish long-term safety.

The 2024 State of Science report from the European Organisation for Research and Treatment of Cancer's Radiation Oncology Scientific Council

BACKGROUND

Radiotherapy (RT) is a central pillar of a multimodal cancer treatment approach. The ongoing advances in the fields of RT, imaging technologies, cancer biology, and others yield the potential to refine the use of RT. The European Organisation for Research and Treatment of Cancer (EORTC) hosted a dedicated workshop to identify and prioritize key research questions and to define future RT-based treatment strategies to improve the survival and quality of life of cancer patients.

METHODS

An initial call for relevant RT research topics led to the formation of workgroups to develop these into new clinical research proposals and projects. The EORTC Radiation Oncology Scientific Council (ROSC) State of Science workshop was held in Brussels, Belgium, in February 2024, bringing together EORTC members and international stakeholders to connect and work on the proposals.

RESULTS

Four topics of interest were identified: I) De-escalation of RT, minimizing toxicity while maintaining patients' quality of life, II) Technology-driven RT utilizing advances in treatment techniques, such as spatially fractionated RT to improve outcomes in patients with bulky disease and localized high tumor burden, III) Biology-driven RT, integrating the rapid advances in cancer biology and functional imaging to guide and personalize RT, and IV) New indications adding value and expanding the use of RT.

CONCLUSION

The EORTC ROSC State of Science workshop prioritized clinical questions to be addressed in prospective clinical research projects to advance RT care and improve patient outcomes.

The Impact of Radiation Dose to Immune Cells in Stage IV Non-Small Cell Lung Cancer in the Era of Immunotherapy

PURPOSE

Thoracic radiotherapy (RT) is now widely used in the treatment of advanced non-small cell lung cancer (NSCLC) as palliative, consolidative or radical therapy. However, RT adversely impacts the immune system, which can be evaluated by calculating the estimated dose of radiation to immune cells (EDRIC). We evaluated the prognostic impact of the EDRIC in patients with advanced NSCLC who received immunotherapy and thoracic RT.

METHODS

We retrospectively enrolled 152 stage IV NSCLC patients who had received first-line immunotherapy and thoracic RT. EDRIC was a model developed by Jin et al., calculated using the number of radiotherapy fractions, mean lung dose, mean heart dose, and mean body dose. Spearman's rank correlation was used to assess the correlations between variables. The relationships of EDRIC (≥5.7 Gy vs. <5.7 Gy) with survival were assessed using Kaplan-Meier and Cox proportional hazard models.

RESULTS

The median PFS and OS were shorter in the EDRIC ≥ 5.7 Gy group (PFS: 10.2 months vs. 18.6 months, P < .0001; OS: 19.8 months vs. 30.2 months, P = .024). In the multivariate model, higher EDRIC was associated with worse PFS (HR = 2.791, P < .0001) and OS (HR = 1.823, P = .028). Additionally, bone metastasis was associated with worse OS (HR = 1.751, P = .022).

CONCLUSION

EDRIC was an independent predictor for PFS and OS in advanced NSCLC patients receiving immunotherapy and RT. These observations necessitate further exploration into techniques to optimize radiation exposure to the immune system in cancer treatment.

ESMO-ESTRO framework for assessing the interactions and safety of combining radiotherapy with targeted cancer therapies or immunotherapy

With the emergence of targeted therapies and immunotherapy, various cellular pathways are utilized to improve tumor control and patient survival. In patients receiving these new agents, radiotherapy is commonly applied with both radical and palliative intent. Combining radiotherapy with targeted therapies or immunotherapy may improve treatment outcomes, but may also lead to increased toxicity. High-quality toxicity data and evidence-based guidelines regarding combined therapy are very limited. The present framework, developed by ESMO and ESTRO, explores the main biological effects and interaction mechanisms of radiotherapy combined with targeted agents or immunotherapy. It addresses general clinical factors to take into consideration when deciding on whether and/or how to combine radiotherapy with these agents. Furthermore, it provides pragmatic, biological mechanism-based clinical considerations for combining radiotherapy with various targeted agents or immunotherapy.

Multimodality treatment in synchronous oligometastatic NSCLC: Analysis of the ETOP CHESS trial

OBJECTIVE

To evaluate the addition of immunotherapy and metastasis-directed stereotactic body radiotherapy (SBRT) to induction chemotherapy followed by definitive local therapy of the locoregional primary tumour in patients with synchronous oligometastatic non-small cell lung cancer (NSCLC).

METHODS

CHESS is a prospective, international, multicentre, single-arm, phase II trial evaluating the efficacy and safety of combined chemotherapy (carboplatin plus paclitaxel), immune checkpoint inhibition (durvalumab) and metastasis-directed SBRT, followed by definitive radiotherapy or surgery of the primary tumour (if no disease progression at the 3-month restaging) and maintenance durvalumab for maximum one year in patients with synchronous oligometastatic NSCLC. The primary endpoint was one-year progression-free survival, aiming to an improvement from 25% to 50%.

RESULTS

A total of 49 patients were enrolled from 11/2019 to 07/2022. Up to 05/2023, the median follow-up was 22 months. Of 47 patients starting treatment, 10 progressed and 2 died before restaging, while 35 proceeded to definitive therapy of the locoregional primary (11surgery, 24 radiotherapy). Among the first 42 evaluable patients, 14 (33%; ≥17 required) reached one year without progression, and the null hypothesis could not be rejected. The one-year overall survival rate for all patients was 74.9% (95% CI: 60.0%-84.9%). Treatment-related grade ≥ 3 adverse events were reported in 34% of patients, with no grade 5 event.

CONCLUSION

The CHESS trial did not meet its primary endpoint. However, the favourable safety profile and promising overall survival provided the basis for further intensification of induction systemic therapy (addition of tremelimumab in a subsequent study cohort; CHESS-Cohort 2).

State-of-the-art of multidisciplinary approach of bone metastasis-directed therapy: review and challenging questions for preparation of a GEMO practice guidelines

Bone is a common secondary site of dissemination during the course of cancer. Bone metastases (BM) can be associated with skeletal-related events (SRE) such as disabling pain, hypercalcemia, and bone instability that leads to pathological fractures or spinal cord compression. SRE contribute to high morbidity as well as, mortality, and have a negative economic impact. Modern management of BM integrates focal treatments (such as radiotherapy, surgery, and interventional radiology), orthoses, and antiresorptive and systemic oncological treatment. The choice of a metastasis-directed therapy depends on the objective of the treatment, the patient characteristics, and the complete assessment of the bone lesion (pain, neurological risk, and instability). In the narrative review present herein, we aim to provide an updated summary of the literature, with description of the advantages and disadvantages of current and emerging strategies in the multimodal treatment of BM and, based on these data, an updated algorithm for the management of BM.

Evaluating Toxicity and Interaction Outcomes of Systemic Therapy and Stereotactic Ablative Radiation Therapy for Oligometastatic Disease: A Secondary Analysis of the Phase 2 SABR-5 Trial

PURPOSE

Although stereotactic ablative radiation therapy (SABR) is known for low toxicity and safety, its combined use with specific systemic therapies requires further investigation. This study aims to evaluate the toxicity of SABR in combination with various systemic therapies.

MATERIALS AND METHODS

A secondary analysis of the SABR-5 trial evaluated grade 2+ and 3+ toxicities post-SABR in patients who had received high-risk or non-high-risk systemic therapies before SABR at 4 predefined intervals: concurrent with SABR, 1 day to 1 week prior, 1 to 2 weeks prior, or 2 to 12 weeks prior. High-risk systemic therapy was a priori defined as drugs that may increase treatment toxicity when delivered in close proximity to SABR. This category encompasses cytotoxic chemotherapy, multitargeted tyrosine kinase inhibitors, CDK 4/6 inhibitors, EGFR inhibitors, anti-VEGF agents, and anti-CTLA-4 agents.

RESULTS

Among 380 patients, grade 2+ toxicity rates were 17.3% (35/202) off systemic therapy, 19.2% (19/99) on non-high-risk therapy, and 42.9% (3/7) on high-risk therapy concurrent with SABR. Grade 3+ rates were 3.5% (7/202), 4.0% (4/99), and 28.6% (2/7), respectively. On multivariable analysis, concurrent use of high-risk systemic therapy was associated with a higher risk of grade 3+ toxic effects (OR, 14.88; P = .009). No significant risk was noted when high-risk drugs were used within 1 week, 2 weeks, or 2 to 12 weeks of SABR or with any non-high-risk drugs. Grade 2+ toxic effects associated with concurrent high-risk systemic therapy were primarily bone/pain related. Increased tumor diameter also elevated grade 2+ toxicity risk (per 1 cm increment; G2+ OR, 1.19; P < .001).

CONCLUSION

Concurrent use of high-risk drugs has demonstrated a potential of increased SABR-related toxicity, warranting caution in their concurrent use with SABR. In contrast, combining non-high-risk drugs (eg, hormonal therapy) with SABR did not increase risk. Further research is essential to identify risks associated with this therapeutic combination.

Tailoring an intravenously injectable oncolytic virus for augmenting radiotherapy

Oncolytic viruses (OVs) combined with radiotherapy (RT) show promise but are limited by challenges such as poor intravenous delivery and insufficient RT-induced DNA damage. In this study, an oncolytic adenovirus (AD) formulation, RadioOnco (AD@PSSP), is developed to improve delivery, infectivity, immune response, and RT efficacy. The multifunctional polyethylenimine (PEI)-selenium-polyethylene glycol (PEG) (PSSP) enhances intravenous delivery, shields the virus from rapid clearance, and enables targeted delivery to tumor sites after RT. The exposed PEI enhances the infectivity of AD through electrostatic interactions, thereby increasing DNA damage after RT by inhibiting the expression of DNA repair proteins, such as CHEK1 and CDK1. Furthermore, AD-PEI captures and delivers RT-induced tumor-released antigens to lymph nodes, activating robust anti-tumor immune responses. Animal model data demonstrate that RadioOnco overcomes RT resistance, targets distant metastases, and promotes long-term immunity, addressing metastasis and recurrence. In summary, this intravenously injectable OV enhances RT synergy through surface modification with multifunctional materials.

Current diagnostic and therapeutical approaches to bone metastases in patients with non-small cell lung cancer: A cross-sectional study

INTRODUCTION

The current study aims to investigate the current practice of bone metastasis management in patients with non-small cell lung cancer.

METHODS

An online questionnaire was administered to 92 oncologists. A survey was developed and revised by dedicated experts and was composed of five sections: i) general and work characteristics, ii) diagnostic issues, ii) bone-targeted agents issues, iii) radiotherapy issues, and iv) supportive care issues. Descriptive statistics was applied.

RESULTS

The 18F-FDG PET is the preferred evaluation for skeletal assessment for both patients with (62 %) and without (54 %) bone lesions at the CT scan; MRI (63 %) and 18F-FDG PET (61 %) are the most chosen radiographic assessments when a bone oligoprogression is suspected. The number of bone metastatic lesions was the main factor considered when deciding whether to start bone-targeted agents (57 %). In choosing between bone-targeted agents, renal toxicity was the most considered factor (62 %). Over half of the participants did not stop the systemic treatment during stereotactic radiotherapy (68 %) and considered re-irradiation on progressive bone metastases at least 6 months after prior radiotherapy (55 %). Overall, 64 % and 41 % of participants assessed patients' body weight and physical activity, respectively. Oral nutritional supplements or a specific diet were recommended by 34 % and 46 % of clinicians; 40 % of them also advised their patients to increase their physical activity levels, while 54 % were worried that exercise might increase the risk of skeletal-related adverse events.

CONCLUSIONS

Lung-cancer dedicated clinicians pay great attention to bone metastases-related diagnostic, bone-targeted agents, and radiotherapy issues, whereas the integration of supportive care approaches seem less standardized.

Nanoradiosentizers with X ray-actuatable supramolecular aptamer building units for programmable immunostimulatory T cell engagement

The insufficient activation and impaired effector functions of T cells in the immunosuppressive tumor microenvironment (TME) substantially reduces the immunostimulatory effects of radiotherapy. Herein, a multifunctional nanoradiosensitizer is established by integrating molecularly engineered aptamer precursors into cisplatin-loaded liposomes for enhancing radio-immunotherapy of solid tumors. Exposure to ionizing radiation (IR) following the nanoradiosensitizer treatment would induce pronounced immunogenic death (ICD) of tumor cells through cisplatin-mediated radiosensitization while also trigger the detachment of the aptamer precursors, which further self-assemble into PD-L1/PD-1-bispecific aptamer-based T cell engagers (CA) through the bridging effect of tumor-derived ATP to direct T cell binding onto tumor cells in the post-IR TME in a spatial-temporally programmable manner. The CA-mediated post-IR tumor-T cell engagement could override the immunosuppressive barriers in TME and enhance T cell-mediated recognition and elimination of tumor cells while minimizing systemic toxicities. Overall, this work offers an innovative approach to enhance the radio-immunotherapeutic efficacy in the clinics.

Targeting USP1 Potentiates Radiation-Induced Type I IFN-Dependent Antitumor Immunity by Enhancing Oligo-Ubiquitinated SAR1A-Mediated STING Trafficking and Activation

The magnitude of Type I interferon (IFN) mediated innate immune response within the tumor microenvironment (TME) critically influences the effectiveness of radiotherapy. Unfortunately, due to a myriad of resistance mechanisms, the double-stranded DNA (dsDNA) signals produced by tumor cells postradiotherapy often induce a diminished response from immune cells. Through chemical screening targeting deubiquitinating enzymes, we identified USP1 (Ubiquitin Specific Peptidase 1) inhibitor as an enhancer of post-radiotherapy dsDNA responses. Mechanistically, within the context of immune-stimulatory cells in TME, USP1 serves as a suppressor in the stress-mediated stages of the cGAS (Cyclic GMP-AMP synthase) -STING (Stimulator of interferon genes protein) signaling pathway, specifically affecting the trafficking of STING from endoplasmic reticulum to Golgi apparatus. It is elucidated that SAR1A (Secretion associated Ras related GTPase 1A) requires K27-linked oligo-ubiquitination to assemble the STING-COP-II (Coat protein II) transport complex for STING trafficking. USP1 counteracts this activation by removing SAR1A ubiquitination, thereby blocking STING trafficking and activation. Consequently, pharmacological USP1 inhibition using ML323 sustains SAR1A ubiquitination and COP-II complex formation, significantly enhancing STING trafficking and subsequent Type I IFN production. This intervention substantially amplifies radiotherapy-induced immune activation in the TME, providing a strategic approach to overcome therapeutic resistance and synergize radiotherapy with immunotherapies.

Efficacy and Safety of Third-Generation EGFR-TKIs Combined with Radiotherapy for Advanced NSCLC with Typical EGFR Mutations: A Retrospective Study

OBJECTIVE

To evaluate the efficacy and safety of third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in combination with radiotherapy (RT) for patients with advanced non-small cell lung cancer (NSCLC) harboring typical EGFR mutations.

METHODS

Patients who received treatment with third-generation EGFR-TKIs alone or in combination with RT were retrospectively enrolled at a single center. The primary endpoint was progression-free survival (PFS). Differences in PFS between the two groups were assessed via the Kaplan-Meier method. Additionally, a subgroup analysis was conducted to further explore the effect of thoracic RT combined with EGFR-TKIs.

RESULTS

This study included a total of 260 patients, among whom 81 patients received third-generation EGFR-TKIs and 179 patients received third-generation EGFR-TKIs plus RT. There was a significant difference in median PFS (mPFS) (13.0 versus 18.1 months, P = 0.0003) between the two groups. Moreover, third-generation EGFR-TKIs plus thoracic RT significantly improved the mPFS (13.0 versus 23.7 months, P < 0.0001). We observed that third-generation EGFR-TKIs plus RT increased the incidence of pneumonia, but all the cases were grade 1 or 2.

CONCLUSION

The addition of RT can delay the occurrence of acquired resistance to third-generation EGFR-TKIs, thereby significantly prolonging PFS in advanced NSCLC patients. RT for primary lung lesions exhibited a significant synergistic effect with EGFR-TKI treatment, and the adverse events of the combination therapy were acceptable.

Survival Without Quality of Life Deterioration in the GORTEC 2014-04 "OMET" Randomized Phase 2 Trial in Patients with Head and Neck Cancer with Oligometastases using Stereotactic Ablative Radiation Therapy (SABR) alone or Chemotherapy and SABR

PURPOSE

Patients with oligometastasis may have prolonged survival with multisite stereotactic ablative radiation therapy (SABR). Evidence to support this paradigm is scarce in squamous cell carcinoma of the head and neck (HNSCC). The multicenter open-label randomized GORTEC 2014-04 (NCT03070366) phase 2 study assesses survival without definitive quality of life (QoL) deterioration of omitting upfront chemotherapy in oligometastatic patients with HNSCC using SABR alone, in the French Head and Neck Intergroup.

METHODS AND MATERIALS

Eligible participants (≥18 years old with 1-3 oligometastases, the Eastern Cooperative Oncology Group score 0-2) were randomly assigned (1:1) to receive chemo-SABR or SABR alone. Salvage treatments were left to the physician's appreciation. The standard therapy was considered to be systemic therapy and SABR (chemo-SABR; EXTREME regimen [5 fluorouracil/platinum/cetuximab]). The primary endpoint was 1-year (±3 months) overall survival rate without definitive deterioration (ie, without subsequent better QoL score) of the global European Organisation for Research and Treatment of Cancer QoL Questionnaire-Core30 score.

RESULTS

Between September 2015 and October 2022, 69 participants were assigned to receive chemo-SABR (N = 35) or SABR alone (N = 34); 57 had lung-only metastases (82.6%), and 40 had isolated metastasis (58.0%). The median baseline QoL score was 66.7 (IQR, [50.0-83.3]). The median follow-up was 55.3 months (95% CI, 45.0-69.7). Of participants (N = 59) evaluable for the primary endpoint, 16 of 29 (55.2%, 90% CI, 0.38-0.71) and 16 of 30 (53.3%, 90% CI, 0.37-0.69) were alive and free of QoL deterioration at 1 year in the SABR-alone and chemo-SABR arms. However, QoL deterioration was deeper with chemo-SABR (50.0; IQR, [41.7-66.7]) than with SABR alone (16.7; IQR, [16.7-41.7]). In intent-to-treat analysis (N = 69), median survival was 42.3 months (95% CI, 26.5-not reached) with chemo-SABR and 41.1 months (95% CI, 32.1-66.9) with SABR alone; median progression-free survival was 12.9 (95% CI, 7.5-17.3) and 7.4 months (95% CI, 4.2-15.6) in the chemo-SABR and SABR alone arms, respectively. Rates of severe treatment-related toxicities were 21 of 35 (60.0%) with chemo-SABR and 3 of 34 (8.8%, no grade 5) with SABR alone.

CONCLUSIONS

Using SABR alone, the omission of upfront EXTREME-based chemotherapy and maintenance cetuximab in oligometastatic patients with HNSCC resulted in similar survival but much less severe QoL deterioration and fewer toxicity rates. SABR alone could be a reasonable alternative in oligometastatic patients with HNSCC.

A Randomized, Multicenter, Phase 2 Trial of Camrelizumab With or Without Metastasis-directed Stereotactic Body Radiation Therapy in Recurrent or Metastatic Nasopharyngeal Carcinoma

PURPOSE

To investigate the efficacy of metastasis-directed therapy (MDT) when added to camrelizumab (Cam) in patients with recurrent or metastatic nasopharyngeal carcinoma (R/M-NPC).

METHODS AND MATERIALS

We conducted a randomized, controlled, multicenter, phase 2 trial in 3 centers from China (NCT04830267). Patients with R/M-NPC, without prior exposure to immunotherapy, who presented with ≥2 lesions, and at least 1 measurable lesion were randomized 1:1 to either Cam alone or Cam plus MDT (Cam+MDT). Patients randomized to the MDT group must have 1 lesion that is amendable to stereotactic body radiation therapy (SBRT) prescribed to 27 Gy in 3 fractions every other day. The primary endpoint was objective response rate (ORR) of unirradiated lesions using Response Evaluation Criteria in Solid Tumors v1.1.

RESULTS

Between April 2021 and August 2023, 39 patients were randomly assigned to receive either Cam (n = 20) or Cam+MDT (n = 19). In total, 17 out of 39 (43.6%) patients had oligometastatic disease (≤3 lesions), 18 out of 39 (46.2%) had liver involvement, and 3 out of 39 (7.7%) had locoregional recurrent disease. ORR of unirradiated lesions did not differ between the treatment groups (26.3% [Cam+MDT] vs 30.0% [Cam], P = 1.0). The disease control rate of unirradiated lesions was 73.7% in the Cam+MDT group compared with 60.0% in the Cam group (P = .571). After a median follow-up of 25.8 months, median progression-free survival was 9.3 (95% CI, 6.2-not reached [NR]) months in the Cam+MDT group and 8.8 (95% CI, 3.3-NR) months in the Cam group (P = .750). Exploratory analyses suggested a longer overall survival (OS) with Cam+MDT for patients with >3 lesions (HR, 0.23; 95% CI, 0.07-0.77; P = .009). G3 and above adverse events were comparable between the treatment groups (15.8% [Cam+MDT] vs 20.0% [Cam]). The overall rate of capillary proliferation was 17.9% (7/39) for the trial.

CONCLUSIONS

Our study did not meet its primary endpoint of superior ORR of unirradiated lesions with the addition of MDT to Cam in patients with R/M-NPC.

Stereotactic body radiotherapy combined with immunotherapy or targeted therapy: a screenshot from Italy on behalf of the Italian Association of Clinical Oncology and Radiotherapy (AIRO)

AIM

Despite the widespread use of immunotherapy (IO) and targeted therapy (TT) in clinical practice, data on toxicity in combination with SBRT are lacking, largely based on retrospective studies and case reports. The present survey, conducted within the AIRO Oligometastatic Study Group, was developed for radiation oncologists to investigate the current clinical practice in Italy regarding hypofractionated SBRT (defined as a dose/fraction ≥ 5 Gy) in cancer patients using IO and TT.

METHODS

The online survey, composed of 19 questions, was developed using the cloud-based platform SurveyMonkey® and was sent to all registered AIRO members using the association's mailing list and was administered online and in anonymous form.

RESULTS

Sixty-eight AIRO members from different Italian regions completed the proposed survey. 59% stated that there is sufficient knowledge within their institute regarding the potential interaction between SBRT and TT/IO. According to 76% of the pool, a multidisciplinary protocol is available in their institute. However, 50% of participants report that interdisciplinary consultation with a radiation oncologist did not always take place. Only 6% of the radiation oncologists stated that they lacked sufficient knowledge to adequately consider the treatment of these patients, while 81% of them felt confident in deciding whether or not to combine SBRT and IO/TT. The 26% and the 37% answered that TT and IO, respectively, should be stopped during RT administration. Regarding which drug types would be of concern when patients are referred for SBRT, the majority of the answers regarded ALK inhibitors (21%), BRAF inhibitors (25%), EGFR inhibitors (26%), immune checkpoint inhibitors (25%) and PARP inhibitors (25%). Only 5% did not consider any of these classes of drugs. Particularly, many radiation oncologists (19%) did not expect a real risk of tumor flare upon discontinuation of TT or IO.

CONCLUSION

The findings from the present survey underscore significant variability in clinical practice regarding the combination of SBRT with IO and TT across Italy. Therefore, there is an urgent need for prospective clinical studies to evaluate the safety and efficacy of combining SBRT with IO/TT. These studies should aim to generate robust data that can inform the development of comprehensive, evidence-based guidelines.

Survival analysis of patients with metastatic head and neck squamous cell carcinoma treated with metastasis-directed radiotherapy and immunotherapy

OBJECTIVE

Immunotherapy combined with chemotherapy is currently the first-line treatment for metastatic head and neck squamous cell carcinoma (HNSCC). This study aims to evaluate whether adding metastasis-directed radiotherapy (MDRT) to immunotherapy and chemotherapy could improve the survival rate of patients with metastatic HNSCC.

MATERIALS AND METHODS

A retrospective analysis was conducted on patients with HNSCC who developed distant metastases after curative treatment. Systemic treatment was determined by the multidisciplinary team, with a programmed cell death-1 (PD-1) inhibitor combined with chemotherapy as the primary approach. The feasibility of radiotherapy was evaluated by clinical and imaging examinations. Stereotactic body radiotherapy (SBRT) was used to deliver different doses according to the number and location of metastatic lesions. Kaplan-Meier method was used to estimate survival, and Cox regression analysis was performed to evaluate the association between clinical factors and survival outcomes.

RESULTS

From January 2018 to June 2023, a total of 94 patients with 164 metastatic sites were included for the analysis. The most common primary tumor was the nasopharynx (77.7%), with the lung being the most frequent site of metastasis (46.8%), followed by bone (37.2%). Radiotherapy was administered to 276 metastatic lesions, with a median dose of 52.3 Gy (range: 24-60 Gy). The median overall survival (OS) was 43.0 months (range: 20.2-65.8). The OS rates at 2 and 5 years were 70.1% (95% CI, 59.7-80.5%) and 30.1% (95%CI 11.7-48.5%), respectively. Univariate and multivariate analysis showed that the number of metastases and the location of the primary tumor were significantly associated with OS.

CONCLUSIONS

In patients with metastatic HNSCC, MDRT combined with immunotherapy and chemotherapy can effectively improve local control and OS. These findings warrant further validation through prospective clinical trials.

Stereotactic body radiotherapy and poly (ADP-ribose) polymerase inhibitors in ovarian cancer: a knowledge and attitudes survey in collaboration with the Italian Association of Radiation Oncology (AIRO) and Multicenter Italian Trials in Ovarian Cancer (MITO) groups

The aim of this study was to present a nationwide survey on the specialist's attitudes towards stereotactic body radiotherapy (SBRT) combined with poly (ADP-ribose) polymerase inhibitors (PARPi) with oligometastatic/oligoprogressive/oligorecurrent ovarian cancer (oMPR-OC) patients. The 19-item questionnaire was developed by specialists and distributed online. Replies were stratified by categories and analyzed using descriptive statistics. Respondents ( N = 100) were radiation oncologists (57%), medical oncologists (32%), and gynecologic oncologists (11%). Fifty-four percent of respondents considered medical oncologists as the primary oncologists for oMPR-OC, while 23% preferred radiation oncologists and 15% favored gynecologic oncologists. Seventy-three percent discuss these cases in the Multidisciplinary Tumor Board, while 15, 6, and 2% send the patients straight to SBRT, surgery, or chemotherapy, respectively. Seventy-four percent of the experts interviewed were treated with SBRT less than 10 oMPR-OC patients. Concomitant treatment was highly heterogeneous, but it had little to no reported side effects. A significant variation in how PARPi is managed during SBRT was found: 34% do not interrupt the administration, while 52% pause and restart it later. Forty-three percent of respondents believe that the PARPi dosage should not be reduced when administered concurrently with SBRT. Sixty-nine percent of respondents believe that the SBRT dose should not be decreased while receiving PARPi if the constraints are met. The majority of respondents (40%) favored expert consensus for enhancing the clinical management of oMPR-OC, while 34% preferred clinical guidelines. A lack of or low toxicity with the combination of PARPi and SBRT was perceived, and a significant degree of heterogeneity concerning clinical protocols for their combination. Moreover, it emphasizes the low number of patients who have received this treatment approach nationwide.

Peptide-based immuno-PET/CT monitoring of dynamic PD-L1 expression during glioblastoma radiotherapy

Real-time, noninvasive programmed death-ligand 1 (PD-L1) testing using molecular imaging has enhanced our understanding of the immune environments of neoplasms and has served as a guide for immunotherapy. However, the utilization of radiotracers in the imaging of human brain tumors using positron emission tomography/computed tomography (PET/CT) remains limited. This investigation involved the synthesis of [18F]AlF-NOTA-PCP2, which is a novel peptide-based radiolabeled tracer that targets PD-L1, and evaluated its imaging capabilities in orthotopic glioblastoma (GBM) models. Using this tracer, we could noninvasively monitor radiation-induced PD-L1 changes in GBM. [18F]AlF-NOTA-PCP2 exhibited high radiochemical purity (>95%) and stability up to 4 h after synthesis. It demonstrated specific, high-affinity binding to PD-L1 in vitro and in vivo, with a dissociation constant of 0.24 nM. PET/CT imaging, integrated with contrast-enhanced magnetic resonance imaging, revealed significant accumulation of [18F]AlF-NOTA-PCP2 in orthotopic tumors, correlating with blood-brain barrier disruption. After radiotherapy (15 Gy), [18F]AlF-NOTA-PCP2 uptake in tumors increased from 9.51% ± 0.73% to 12.04% ± 1.43%, indicating enhanced PD-L1 expression consistent with immunohistochemistry findings. Fractionated radiation (5 Gy × 3) further amplified PD-L1 upregulation (13.9% ± 1.54% ID/cc) compared with a single dose (11.48% ± 1.05% ID/cc). Taken together, [18F]AlF-NOTA-PCP2 may be a valuable tool for noninvasively monitoring PD-L1 expression in brain tumors after radiotherapy.

The role of external-beam radiotherapy for differentiated thyroid cancer

The treatment options for differentiated thyroid cancer (DTC) are surgery, thyroid stimulating hormone suppression, radioactive iodine, and multitargeted tyrosine kinase inhibitors. The role of external-beam radiotherapy (EBRT) for DTC is controversial because of the lack of randomized controlled trials, but prospective single-arm studies and propensity score matching analyses have shown its efficacy and safety. This review discusses the role of EBRT after resection of gross disease, when there is a high risk of locoregional failure, as well as its role for locoregionally gross recurrent and unresectable disease. As in other tumor sites, EBRT has an important role in the palliative management and local control of patients with metastatic DTC, especially with bone and brain metastases.

Navigating through recent evidence on locoregional breast cancer radiotherapy: an initiative by the scientific association of Swiss radiation oncology

PURPOSE

Breast cancer (BC) is the most prevalent cancer in women and radiotherapy (RT) is an integral part of its treatment. High-level evidence guides clinical decisions, but given the abundance of guidelines, a need to navigate within the evidence has been identified by the board of the Scientific Association of Swiss Radiation Oncology (SASRO). A pilot project was initiated aiming to create an overview of recent clinically relevant evidence for BC RT, to make it easily available to (radiation) oncologists and radiation oncologists in training.

METHODS

A panel of 10 radiation oncology experts for BC RT, one expert in BC surgery, and one expert in BC medical oncology critically reviewed the relevant literature. The panel comprehensively represented different geographical regions of Switzerland as well as university, cantonal, and private institutions. We sought to create a consensual overview of the most relevant questions in BC RT today, accompanied by the most recent and relevant available evidence.

RESULTS

From January 2023 to January 2024, the panel met four times to review and work on an initial draft. The final draft was reviewed and accepted by all panelists. We hereby publish this work to make it available to international audiences. After publication, the work will be made available to all SASRO members on the SASRO website. This work is to be updated every 2 years.

CONCLUSION

The identified need was addressed with a successful pilot project and will be further expanded upon in other tumor pathologies.

Efficacy of innovative systemic treatments in combination with radiotherapy for bone metastases: a GEMO (the European Study Group of Bone Metastases) state of the art

The management of bone metastases (BoM) requires a multidisciplinary approach to prevent complications, necessitating updated knowledge in light of the rapid advancements in systemic treatments and surgical, interventional radiology or radiation techniques. This review aims to discuss efficacy of new systemic treatments on BoM, the benefits of radiotherapy adjunction, and the optimal methods for combining them. Preliminary evidence suggesting reduced efficacy of immune checkpoint inhibitors (ICI), and several multi-kinase inhibitors regarding BoM may encourage early use of radiotherapy (RT). Systemic treatment efficacy modulation by RT and ablative RT strategies are explored. Concerns for increased side effects for several kinase inhibitors and double ICI in combination with RT imply suspending those systemic treatments during RT. Various timing strategies to combine prostate hormone therapies and RT are developed. Emerging internal vectorized radiotherapy molecules necessitate developing new combination strategies with RT. Further prospective data collection and comparative trials should be encouraged.

Ongoing prospective studies on reirradiation: A systematic review of a clinical trials database

INTRODUCTION

Reirradiation has gained increasing interest, as advances in systemic therapy increase the survival of patients with cancer, and modern radiation techniques allow more precise treatments. However, high-quality prospective evidence on the safety and efficacy of reirradiation to guide clinical practice remains scarce. This systematic review evaluates ongoing prospective studies on reirradiation to identify research gaps and priorities.

METHODS

A systematic review of ClinicalTrials.gov was conducted on July 11, 2024, using search terms related to reirradiation. Inclusion criteria were prospective studies that were "recruiting," "not yet recruiting," or "active, not recruiting." Studies with published results, retrospective, and in-silico studies were excluded. The review followed PRISMA 2020 guidelines and recommendations for systematic searches of clinical trial registries.

RESULTS

Among 1026 identified studies, 307 were screened, 99 were included. Fourty (40%) focused on central nervous system (CNS), 23 (23%) head and neck, and 17 (17%) on pelvic reirradiation. Most studies (90%) were interventional, with 32 (32%) phase II and 4 (4%) phase III trials. Sixteen trials were randomized (RCTs), including the 4 phase III trials for recurrent glioblastoma, rectal and nasopharyngeal cancer. Ten dose escalation trials focus on recurrent prostate, rectal, and non-small cell lung cancer as well as glioma. Modern high-precision radiotherapy techniques were frequently used, with 21 (21%) studies using stereotactic radiotherapy and 17 (17%) using particle therapy. Combinations with systemic therapies were investigated in 41 (41%) studies.

CONCLUSION

Ongoing studies most frequently focus on CNS, head and neck, and pelvic reirradiation. There remains a critical need for RCTs, in particular for lung, breast, and gynecological cancers. Dose escalation trials, application of precision radiation techniques and combinations with modern systemic therapy may help define the optimal multimodality treatment schedules.

Evaluating the effectiveness of cytoreductive surgery in oligometastatic prostate cancer: insights from quantitative analysis and retrospective cohort studies

BACKGROUND

Oligometastatic prostate cancer (OmPCa) is characterized by a restricted number of metastatic lesions confined to a limited organ range, presenting a distinct clinical challenge. The role of cytoreductive prostatectomy (CRP) in managing this specific metastatic stage has gained attention but remains controversial. This study aims to assess the effectiveness of CRP in OmPCa by synthesizing outcomes from previous studies and analyzing data from a multicenter, retrospective cohort.

METHODS

We focused on evaluating overall survival (OS), progression-free survival (PFS), cancer-specific survival (CSS), and castration-resistant prostate cancer-free survival (CRPCFS) as primary outcomes. A multicenter comparative retrospective analysis was also conducted on OmPCa patients treated with CRP versus those receiving androgen deprivation therapy (ADT) alone from January 2008 to June 2018. We gathered and analyzed data on patient demographics, tumor characteristics, surgical outcomes, and survival metrics.

RESULTS

The quantitative analysis included 18 studies [2 randomized controlled trials (RCTs) and 16 non-RCT studies], comprising a total of 1733 patients with OmPCa, and this is the largest number of samples included in the same subject research at present. The pooled analysis demonstrated that cytoreductive surgery was associated with significantly improved OS [hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.40-0.60], PFS (HR 0.39, 95% CI 0.27-0.51), CSS (HR 0.44, 95% CI 0.23-0.65), and CRPCFS (HR 0.48, 95% CI 0.36-0.59) compared to nonsurgical management. In addition, OS, PFS, and CRPCFS showed better results in the CRP group in all analyses (RCTs and non-RCTs). Additionally, in our multicenter retrospective research analysis, 64 patients with OmPCa were included, 32 underwent CRP (50%) and 32 underwent ADT alone (50%). The median follow-up time was 40.1 (18.9-51.3) months. The OS ( P =0.0182), PFS ( P =0.0297), and CRPCFS ( P =0.0125) had statistical differences between the two matched cohorts. Moreover, we observed 8 (25%) cases of perioperative complications, with the most common being urinary incontinence (9.4%).

CONCLUSIONS

Incorporating CRP alongside ADT in the treatment protocol for OmPCa significantly enhances patient outcomes in terms of OS, PFS, and CRPC-free survival, underscoring the potential benefit of this surgical approach in the specified patient population.

Stereotactic Body Radiation Therapy for Primary Renal Cell Carcinoma: A Case-Based Radiosurgery Society Practice Guide

Traditionally, renal cell carcinoma (RCC) was considered a radioresistant tumor, thereby limiting definitive radiation therapy management options. However, several recent studies have demonstrated that stereotactic body radiation therapy (SBRT) can achieve high rates of local control for the treatment of primary RCC. In the setting of expanding use of SBRT for primary RCC, it is crucial to provide guidance on practical considerations such as patient selection, fractionation, target delineation, and response assessment. This is particularly important in challenging scenarios where a paucity of evidence exists, such as in patients with a solitary kidney, bulky tumors, or tumor thrombus. The Radiosurgery Society endorses this case-based guide to provide a practical framework for delivering SBRT to primary RCC, exemplified by 3 cases. This article explores topics of tumor size and dose fractionation, impact on renal function and treatment in the setting of a solitary kidney, and radiation's role in the management of inferior vena cava tumor thrombus. Additionally, we review existing evidence and expert opinion on target delineation, advanced techniques such as magnetic resonance imaging guided SBRT, and SBRT response assessment.

Role of the TME in immune checkpoint blockade resistance of non-small cell lung cancer

Primary and secondary resistance to immune checkpoint blockade (ICB) reduces its efficacy. The mechanisms underlying immunotherapy resistance are highly complex. In non-small cell lung cancer (NSCLC), these mechanisms are primarily associated with the loss of programmed cell death-ligand 1 (PD-L1) expression, genetic mutations, circular RNA axis and transcription factor regulation, antigen presentation disorders, and dysregulation of signaling pathways. Additionally, alterations in the tumor microenvironment (TME) play a pivotal role in driving immunotherapy resistance. Primary resistance is mainly attributed to TME alterations, including mutations and co-mutations, modulation of T cell infiltration, enrichment of M2 tumor-associated macrophages (M2-TAMs) and mucosal-associated invariant T (MAIT) cells, vascular endothelial growth factor (VEGF), and pulmonary fibrosis. Acquired resistance mainly stems from changes in cellular infiltration patterns leading to "cold" or "hot" tumors, altered interferon (IFN) signaling pathway expression, involvement of extracellular vesicles (EVs), and oxidative stress responses, as well as post-treatment gene mutations and circadian rhythm disruption (CRD). This review presents an overview of various mechanisms underlying resistance to ICB, elucidates the alterations in the TME during primary, adaptive, and acquired resistance, and discusses existing strategies for overcoming ICB resistance.

Local treatment for oligoprogressive metastatic sites of breast cancer: efficacy, toxicities and future perspectives

Metastatic breast cancer (MBC) is still an incurable disease, which eventually develops resistance mechanisms against systemic therapies. While most patients experience widespread disease progression during systemic treatment (ST), in some cases, progression may occur at a limited number of metastatic sites. Evidence from other malignancies suggests that local treatment with stereotactic ablative radiotherapy (SABR) of oligoprogressive disease (OPD) may allow effective disease control without the need to modify ST. Available evidence regarding local treatment of oligoprogressive breast cancer is limited, mostly consisting of retrospective studies. The only randomized data come from the randomized CURB trial, which enrolled patients with oligoprogressive disease, including both small cell lung cancer and breast cancer patients, and did not show a survival benefit from local treatment in the latter group. However, local treatment of oligoprogressive MBC is still considered in clinical practice, especially to delay the switch to more toxic STs. This review aims to identify patients who may benefit from this approach based on the current available knowledge, focusing also on the potential risks associated with the combination of radiotherapy (RT) and ST, as well as on possible future scenarios.

The Evolving Role of Neoadjuvant Radiation Therapy in Pancreatic Adenocarcinoma

BACKGROUND/OBJECTIVES

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers. Surgical resection is the most reliable chance for cure, but high rates of positive margins and local failure persist. Neoadjuvant therapies (NAT), including chemotherapy and radiation therapy (RT), are being explored to improve surgical outcomes, particularly in borderline resectable (BRPC) and locally advanced pancreatic cancer (LAPC). This review aims to summarize the current landscape and future directions for neoadjuvant RT (NART) in PDAC.

METHODS

The review includes a detailed analysis of past and ongoing clinical trials investigating various NART approaches in PDAC, with an emphasis on different RT techniques, fractionation schemes, and their integration into multimodal treatment strategies.

RESULTS

Early evidence suggests that NART can improve resection margins and local control. However, recent trials, including the Alliance A021501 and LAP-07 trials, have failed to demonstrate significant survival benefits with the addition of RT to NAT. Nevertheless, nuances in trial design and execution continue to keep the question of NART open. Newer approaches, such as stereotactic magnetic resonance-guided adaptive radiation therapy (SMART), show promise in improving local control and survival, but further phase 3 trials are needed.

CONCLUSIONS

While NART has shown potential in improving local control in PDAC, its impact on overall survival remains unclear. Ongoing trials, particularly those utilizing advanced techniques like SMART, are critical in defining the role of RT in the neoadjuvant setting for PDAC. Collaboration across multidisciplinary teams is essential to optimize treatment strategies and trial outcomes.

ACROPath Oligometastases: The American College of Radiation Oncology Clinical Pathway

Radiation oncology is among the most data-driven specialties in medicine. Recently, a wealth of peer-reviewed data has been published supporting the treatment of oligometastatic malignancies, demonstrating improved survival with metastasis-directed therapy, such as stereotactic body radiation therapy (SBRT), when combined with appropriate patient selection and treatment. However, there are currently few, if any, established guidelines that synthesize the abundance of data specific to radiotherapy into a single, easily accessed resource for clinicians. ACROPath® is a major initiative of the American College of Radiation Oncology (ACRO) that aims to present aggregated clinical pathway data in a highly usable format that is readily accessible to clinicians at the point of care in real time. The oligometastases pathway is the first published algorithm in this collection, with additional pathways anticipated in future publications. Clinical radiation oncologists with expertise in the treatment and management of oligometastatic disease were recruited from across ACRO's diverse membership, including both academic and private practice physicians, to ensure a broad-based experience and insight. Individual participants were assigned subsections of the pathway for guideline development, and then, each subsection was presented to the full group for evaluation and consensus development based on published data. Rather than presenting an unstructured set of treatment options, as is common in other treatment guidelines, this initiative aimed to categorize appropriate treatments based on published clinical evidence in a hierarchy further ranked by efficacy, toxicity, and cost. Based on these strata, treatment recommendations were collated and grouped into three rank categories (gold, silver, or bronze) to denote the degree of applicability. The team assembled an interactive document that will eventually be available online, and it is summarized in detail here. Recommendations are grouped both by the anatomic site of metastasis and by the primary tumor type, recognizing that original histology might impact the treatment differently in different anatomic locations. After a review of available published clinical evidence, the committee reached a consensus on all recommendations presented, categorizing each option as gold, silver, or bronze to guide clinicians appropriately. This first iteration of ACROPath® Oligometastases represents one of the few comprehensive clinical decision support tools available for managing patients with limited metastatic disease. It presents available data in a highly accessible, easily used reference, which will be formally reviewed and updated by the committee as frequently as emerging data requires, likely at six- to 12-month intervals.

Diagnosis and management of brain radiation necrosis

Brain radiation necrosis (BRN) is a significant and complex side effect of stereotactic radiotherapy (SRT). Differentiating BRN from local tumor recurrence is critical, requiring advanced diagnostic techniques and a multidisciplinary approach. BRN typically manifests months to years post-treatment, presenting with radiological changes on MRI and may produce neurological symptoms. Key risk factors include the volume of irradiated brain tissue, the radiation dose, and prior radiotherapy history. This manuscript reviews the diagnostic process for BRN, emphasizing the importance of assessing baseline risk, clinical evaluation, and advanced imaging modalities. Multimodal imaging enhances diagnostic accuracy and aids in distinguishing BRN from tumor relapse. Therapeutic management varies based on symptoms. Asymptomatic BRN may be monitored with regular imaging, while symptomatic BRN often requires corticosteroids to reduce inflammation. Emerging therapies like bevacizumab have shown promise in clinical trials, with significant radiographic and symptomatic improvement. Surgical intervention may be necessary for histological confirmation and severe, treatment-resistant cases. Ongoing research aims to improve diagnostic accuracy and treatment efficacy, enhancing patient outcomes and quality of life. This review underscores the need for a multidisciplinary approach and continuous advancements to address the challenges posed by BRN in brain tumor patients.

Stereotactic body radiation therapy on abdominal-pelvic lymph node oligometastases: a systematic review on toxicity

BACKGROUND AND PURPOSE

To review available data on toxicity during and/or after treatment of abdominal-pelvic lymph node oligometastases (A-P LN) with stereotactic body radiation therapy (SBRT) and to provide an overview of adverse events and its relation to dose or fractionation.

MATERIAL AND METHODS

For this systematic review, we searched MEDLINE, Embase, Web of Science Core Collection, and CINAH for studies published between the database inception and October 3rd, 2023. Inclusion criteria were (1) patients with 1-5 A-P LN oligometastases, (2) treatment with SBRT to a median prescribed dose of ≥55 Gy BED10, and (3) description of acute and/or late toxicity. There were no language or date restrictions.

RESULTS

A total of 35 studies, including 1,512 patients, were selected. Late grade 3 and 4 adverse events occurred in 0.6% and 0.1% of the patients treated for A-P LN oligometastases. All late adverse events grade ≥ 3 occurred after treatment of the tumor with a minimum BED10 of 72 Gy. Of the 11 patients with severe late toxicity, five patients were re-irradiated. Late grade 2 and 1 toxicity was reported in 3.4% and 8.3% of the patients. Acute toxicity grades 4, 3, 2, and 1 occurred in 0.1%, 0.2%, 4.4%, and 19.8% of the patients, respectively.

INTERPRETATION

SBRT for A-P LN oligometastases show low toxicity rates. Nearly 50% of late adverse events ≥ grade 3 were associated with re-irradiation.

Oxygen self-supplying nanoradiosensitizer activates cGAS-STING pathway to enhance radioimmunotherapy of triple negative breast cancer

Radiotherapy (RT)-mediated immune activation is insufficient for effective therapy of triple-negative breast cancer (TNBC) due to the immunosuppressive tumor microenvironment. Herein, we developed an oxygen self-supplying nanoradiosensitizer to activate immunogenic cell death (ICD) and the cGAS-STING signaling pathway, elevating the anti-tumor immune response and improving radioimmunotherapy for TNBC. The nanoradiosensitizer was fabricated using astragaloside liposome-encapsulated FePt alloy and MnO nanocrystals (ALFM). The ALFM targeted the glucose transporter-1 (GLUT-1) receptor in TNBC and effectively entered tumor cells. Subsequently, the ALFM responded to the weakly acidic tumor microenvironment and degraded, releasing FePt and Mn2+ ions. The released Mn2+ ions not only elevated cellular ROS levels via a Fenton-like reaction but also activated the cGAS-STING signaling pathway, which stimulated the anti-tumor immune response. In addition, the FePt alloy catalyzed a cascade reaction, producing ROS and O2 in tumor cells, alleviating tumor hypoxia, and enhancing the RT effect. Besides, ROS-mediated cell damage induced the ICD effect in TNBC, promoted dendritic cell maturation and the infiltration of cytotoxic T lymphocytes, ultimately eliciting cancer immunotherapy. In vivo experimental results demonstrated that ALFM effectively activated the antitumor immune response and improved the radioimmunotherapy effect for TNBC. Overall, this work presents an effective strategy for enhanced radioimmunotherapy of TNBC. Subsequently, the ALFM responded to weak acidic tumor microenvironment, and then degraded along with the release of FePt and Mn2+ ions. The released Mn2+ ions not only elevated cellular ROS level via Fenton-like reaction, but also activated cGAS-STING signal pathway, which activated anti-tumor immune response. In addition, FePt alloy catalyzed cascade reaction and then produced ROS and O2 in tumor cells, relieving tumor hypoxia and enhancing RT effect. Besides, ROS-mediated cell damage induced ICD effect of TNBC, promoted dendritic cells maturation and the infiltration of cytotoxic T lymphocytes, eventually elicited antitumor immunotherapy. In vivo experimental results demonstrated that ALFM effectively activated antitumor immune response, improved radioimmunotherapy effect of TNBC. Overall, this work provided a complete new strategy for enhanced radioimmunotherapy of TNBC.

Gut microbiome model predicts response to neoadjuvant immunotherapy plus chemoradiotherapy in rectal cancer

BACKGROUND

Accurate evaluation of the response to preoperative treatment enables the provision of a more appropriate personalized therapeutic schedule for locally advanced rectal cancer (LARC), which remains an enormous challenge, especially neoadjuvant immunotherapy plus chemoradiotherapy (nICRT).

METHODS

This prospective, multicenter cohort study enrolled patients with LARC from 6 centers who received nICRT. The dynamic variation in the gut microbiome during nICRT was evaluated. A species-level gut microbiome prediction (SPEED) model was developed and validated to predict the pathological complete response (pCR) to nICRT.

FINDINGS

A total of 50 patients were enrolled, 75 fecal samples were collected from 33 patients at different time points, and the pCR rate reached 42.4% (14/33). Lactobacillus and Eubacterium were observed to increase after nICRT. Additionally, significant differences in the gut microbiome were observed between responders and non-responders at baseline. Significantly higher abundances of Lachnospiraceae bacterium and Blautia wexlerae were found in responders, while Bacteroides, Prevotella, and Porphyromonas were found in non-responders. The SPEED model showcased a superior predictive performance with areas under the curve of 98.80% (95% confidence interval [CI]: 95.67%-100%) in the training cohort and 77.78% (95% CI: 65.42%-88.29%) in the validation cohort.

CONCLUSIONS

Programmed death 1 (PD-1) blockade plus concurrent long-course CRT showed a favorable pCR rate and is well tolerated in microsatellite-stable (MSS)/mismatch repair-proficient (pMMR) patients with LARC. The SPEED model can be used to predict the pCR to nICRT based on the baseline gut microbiome with high robustness and accuracy, thereby assisting clinical physicians in providing individualized management for patients with LARC.

FUNDING

This research was funded by the China National Natural Science Foundation (82202884).

Risk of radionecrosis in HER2-positive breast cancer with brain metastasis receiving trastuzumab emtansine (T-DM1) and brain stereotactic radiosurgery

OBJECTIVES

To investigate the potential relationship between trastuzumab emtansine (T-DM1) treatment and radionecrosis induced by brain stereotactic radiosurgery (SRS) in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

MATERIALS AND METHODS

Patients with HER2-positive breast cancer who were diagnosed with brain metastasis and received both SRS and HER2-targeted agents between 2012 and 2022 were retrospectively analyzed. Patients who received T-DM1 within 1 year (either before or after) of SRS were considered as 'T-DM1 exposure (+)'. T-DM1 exposure (-) group had other HER2-targeted agents or received T-DM1 more than 1 year before or after SRS. Symptomatic radionecrosis was defined as Common Terminology Criteria for Adverse Events grade 2 or greater.

RESULTS

A total of 103 patients with 535 treatment sessions were included from seven tertiary medical centers in Korea and Italy. The median follow-up duration was 15.5 months (range 1.1-101.9). By per-patient analysis, T-DM1 exposure (+) group had an increased risk of overall radionecrosis after multivariate analysis (HR 2.71, p = 0.020). Additionally, T-DM1 exposure (+) group was associated with a higher risk of symptomatic radionecrosis compared to T-DM1 exposure (-) patients (HR 4.34, p = 0.030). In per-treatment analysis, T-DM1 exposure (+) was linked to higher incidences of overall (HR 3.13, p = 0.036) and symptomatic radionecrosis (HR 10.4, p = 0.013) after multivariate analysis. A higher prevalence of radionecrosis was observed with T-DM1 exposure (+) and a previous history of whole brain radiotherapy.

CONCLUSION

An increased risk of radionecrosis was observed in patients receiving T-DM1 with brain SRS. Further research is needed to better understand the optimal sequence and interval for administering T-DM1 and SRS.

Delayed neurotoxicity in HER2-positive breast cancer: a case series on combined SRS and T-DM1 treatment

This case series presents four instances of late neurotoxicity observed in HER2-positive breast cancer patients with brain metastases following treatment with stereotactic radiosurgery (SRS) and subsequent trastuzumab emtansine (T-DM1) therapy. Despite initial control of intracranial disease, patients experienced neurological deterioration months to years post-treatment. Radiological assessments revealed distinct patterns consistent with radiation necrosis, particularly in areas previously treated with SRS and subsequent T-DM1 administration. These changes, characterized by enlarging cystic masses with hemorrhagic components, emphasize the importance of vigilant monitoring in patients undergoing combined SRS and T-DM1 therapy for brain metastatic breast cancer. This report underscores the need for further investigation into the long-term effects of combining SRS with novel systemic therapies, particularly in HER2-positive breast cancer patients with brain metastases. Understanding and mitigating late neurotoxicity are critical for optimizing treatment strategies and improving patient outcomes.

Acute toxicity in patients with oligometastatic cancer following metastasis-directed stereotactic body radiotherapy: An interim analysis of the E2-RADIatE OligoCare cohort

AIM

To evaluate acute toxicity at 6 months after stereotactic body radiotherapy (SBRT) in patients with oligometastatic cancer within the OligoCare cohort.

MATERIAL AND METHODS

OligoCare is a prospective, registry-based, single-arm, observational study that aims to report prospective real-world data of patients with oligometastases from solid cancer treated with SBRT (NCT03818503). Primary tumor included non-small cell lung cancer (NSCLC), breast cancer (BC), colorectal cancer (CRC), and prostate cancer (PC). This analysis addresses a secondary endpoint of the trial, acute toxicity within 6 months after SBRT.

RESULTS

Out of 1,597registered patients, 1'468 patients were evaluated for acute toxicity. Globally, 290 (20 %) had NSCLC primary disease, 227 (16 %) had BC, 293 (20 %) had CRC, and 658 (45 %) had PC. Concomitant systemic treatment was administered in 527 (35.9 %) patients. According to the EORTC/ESTRO oligometastatic disease (OMD) classification, 828 (56 %) patients had de novo OMD, 464 (32 %) repeat OMD, and 176 (12 %) induced OMD. Acute grade ≥ 3 SBRT related adverse events were reported in 8 (0.5 %) patients, including 2 (0.1 %) fatal AEs. In particular, 6 (0.4 %) grade 3 events were: 1 empyema, 1 pneumonia, 1 radiation pneumonitis, 1 radiation skin injury, 1 decreased appetite, and 1 bone pain. Among those 2 occurred in NSCLC patients, 2 in BC patients, and 1 in CRC and PC patients each. The two (0.1 %) grade 5 toxicity were represented by: pneumonitis and cerebral hemorrhage.

CONCLUSION

OligoCare is the largest prospective registry cohort on oligometastatic disease. Acute toxicity within 6 months was low, confirming the safety of SBRT in the treatment of oligometastases.

Cyclin-dependent kinase 4/6 inhibitors combined with stereotactic ablative radiotherapy in oligometastatic HR-positive/HER2-negative breast cancer patients

OBJECTIVES

Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) have significantly improved the survival of patients with hormone receptor-positive HER2-negative advanced breast cancer (ABC). Although stereotactic ablative radiotherapy (SABR) is used more often in routine clinical practice, data on the safety and efficacy of combining SABR with CDK4/6i are lacking. Herein, we present the results of SABR combined with CDK4/6i in ABC.

METHODS

Patients with ABC who received CDK4/6i and SABR between 2018 and 2023 were analysed.

RESULTS

Among 384 patients treated with CDK4/6i, 34 patients received 44 courses of SABR. Two-year progression-free survival (PFS) was 63.6% (95% CI, 45.8-88.3), and the median PFS was 32 months. Three-year overall survival (OS) was 88.9% (95% CI, 77.7-100). Two-year local control (LC) was 92.7% (95% CI, 83.4-100). Median OS and LC were not reached. The subgroup analysis showed the difference in survival between oligometastatic patients (OMD) and non-OMD subgroup. Two-year PFS was 69.2% (95% CI, 44.5-100) in OMD compared with 57.4% (95% CI, 36-91.7) in the non-OMD (P = .042). Three-year OS was 90% (95% CI, 73.2-100) in OMD compared with 86.2% (95% CI, 70-100) in the non-OMD (P = .67). Median PFS and OS in the non-OMD were 26 and 56 months, respectively, and were not reached in OMD. Fifteen patients required CDK4/6i dose reduction, and 2 discontinued treatment due to toxicity. No difference in high-grade toxicity was observed between the sequential and concurrent SABR.

CONCLUSION

The addition of SABR to CDK4/6i seems to be safe and effective, especially in patients with oligometastatic disease.

ADVANCES IN KNOWLEDGE

In advanced breast cancer patients treated with CDK4/6i, SABR provides a high local control and may provide additional benefit in an oligometastatic setting.

Focal therapy for oligometastatic and oligoprogressive renal cell carcinoma: a narrative review

Metastatic renal cell carcinoma (RCC) can present with oligometastatic disease and/or develop oligoprogression following systemic therapy. Cytoreductive and focal metastasis-directed therapy options include resection, stereotactic ablative radiation and thermal ablation. Aggressive focal therapy may allow delay in initiation of or modification to systemic therapy and improve clinical outcomes. In this narrative review we synthesize current practice guidelines and prospective data on focal therapy management options and highlight future research. Patient selection and the choice of focal treatment techniques are controversial due to limited and heterogeneous data and patients may benefit from multidisciplinary evaluation. Prospective comparative trials with clearly defined inclusion criteria and relevant end points are needed to clarify the risks and benefits of different approaches.

Abscopal effect: from a rare phenomenon to a new frontier in cancer therapy

Radiotherapy (RT) controls local lesions, meantime it has the capability to induce systemic response to inhibit distant, metastatic, non-radiated tumors, which is referred to as the "abscopal effect". It is widely recognized that radiotherapy can stimulate systemic immune response. This provides a compelling theoretical basis for the combination of immune therapy combined with radiotherapy(iRT). Indeed, this phenomenon has also been observed in clinical treatment, bringing significant clinical benefits to patients, and a series of basic studies are underway to amplify this effect. However, the molecular mechanisms of immune response induced by RT, determination of the optimal treatment regimen for iRT, and how to amplify the abscopal effect. In order to amplify and utilize this effect in clinical management, these key issues require to be well addressed; In this review, we comprehensively summarize the growing consensus and emphasize the emerging limitations of enhancing the abscopal effect with radiotherapy or immunotherapy. Finally, we discuss the prospects and barriers to the current clinical translational applications.

Palliative Thoracic Radiotherapy in the Era of Modern Cancer Care for NSCLC

Palliative thoracic radiotherapy provides rapid and effective symptom relief in approximately two-thirds of NSCLC patients treated. In patients with poor performance status, the degree of palliation appears unrelated to the radiation dose or fractionation schedule. Conversely, in patients with good performance status, higher radiation doses administered over longer periods have shown modest survival benefits. These findings stem from studies conducted before the advent of immunotherapy and targeted therapy in clinical practice. Currently, there are no large prospective studies specifically dedicated to palliative radiotherapy conducted in this new treatment era. Modern radiotherapy technologies are now widely available and are increasingly used for palliative purposes in selected patients, reflecting the expanded array of therapeutic options for disseminated NSCLC and improved prognosis. Some traditional tenets of palliative thoracic radiotherapy, such as the improvement of overall survival with a protracted radiation schedule and the use of simple, cost-effective radiation techniques for palliative purposes, may no longer hold true for patients receiving immunotherapy or targeted therapy. The application of IMRT or SBRT in the context of palliative radiotherapy for NSCLC is not yet sufficiently explored, and this is addressed in this review. Moreover, new risks associated with combining palliative radiotherapy with these systemic treatments are being explored and are discussed within the context of palliative care. The optimal timing, doses, fractionation schedules, and treatment volumes for radiotherapy combined with immunotherapy or targeted therapy are currently subjects of investigation. In emergencies, radiotherapy should be used as a life-saving measure without delay. However, for other indications of palliative thoracic radiotherapy, decisions regarding doses, timing relative to systemic treatments, and treatment volumes should be made in a multidisciplinary context, considering the patient's prognosis, anticipated outcomes, and access to potentially effective treatments. We still lack robust data from prospective studies on this matter. This review examines and discusses available evidence on the use of palliative thoracic radiotherapy within the framework of modern treatment strategies for NSCLC.

Targeted RT study: results on early toxicity of targeted therapies and radiotherapy

PURPOSE/OBJECTIVE

Currently, there are few prospective data on the tolerability of combining targeted therapies (TT) with radiation therapy (RT). The objective of this prospective study was to assess the feasibility and toxicity of pairing RT with concurrent TT in cancer patients. The aim was to enhance the existing evidence base for the simultaneous administration of targeted substances together with radiotherapy.

METHODS

Prospective study enrollment was conducted at a single institution between March 1, 2020, and December 31, 2021, for all patients diagnosed with histologically confirmed cancer who underwent external beam radiotherapy in combination with targeted therapy. The study, known as the "targeted RT study," was registered in the German Clinical Trials Register under DRKS00026193. Systematic documentation of the toxicity profiles of different targeted therapies was performed, and the assessment of acute toxicity followed the guidelines of the National Cancer Institute Common Terminology Criteria for Adverse Events Version v5.0.

RESULTS

A total of 334 patients underwent 683 radiation therapy series. During the course of RT, 51 different TT substances were concurrently administered. External beam radiotherapy was employed for various anatomical sites. The combination of RT and concurrent TT administration was generally well tolerated, with no instances of severe acute toxicity observed. The most commonly reported toxicity was fatigue, ranging from mild to moderate Common Terminology Criteria for Adverse Events (CTCAE) °I-°III. Other frequently observed toxicities included dermatitis, dyspnea, dysphagia, and dry cough. No toxicity greater than moderate severity was recorded at any point. In only 32 patients (4.7% of evaluated RT series), the concurrent substance administration was discontinued due to side effects. However, these side effects did not exceed mild severity according to CTCAE, suggesting that discontinuation was a precautionary measure. Only one patient receiving Imatinib treatment experienced a severe CTCAE °III side effect, leading to discontinuation of the concurrent substance due to the sudden occurrence of melaena during RT.

CONCLUSION

In conclusion, the current study did not demonstrate a significant increase or additional toxicity when combining radiotherapy and concurrent targeted therapy. However, additional research is required to explore the specific toxicity profiles of the various substances that can be utilized in this context.

TRIAL REGISTRATION NUMBER

DRKS00026193. Date of registration 12/27/2022 (retrospectively registered).

Cracking the Codes behind Cancer Cells' Immune Evasion

Immune evasion is a key phenomenon in understanding tumor recurrence, metastasis, and other critical steps in tumor progression. The tumor microenvironment (TME) is in constant flux due to the tumor's ability to release signals that affect it, while immune cells within it can impact cancer cell behavior. Cancer cells undergo several changes, which can change the enrichment of different immune cells and modulate the activity of existing immune cells in the tumor microenvironment. Cancer cells can evade immune surveillance by downregulating antigen presentation or expressing immune checkpoint molecules. High levels of tumor-infiltrating lymphocytes (TILs) correlate with better outcomes, and robust immune responses can control tumor growth. On the contrary, increased enrichment of Tregs, myeloid-derived suppressor cells, and M2-like anti-inflammatory macrophages can hinder effective immune surveillance and predict poor prognosis. Overall, understanding these immune evasion mechanisms guides therapeutic strategies. Researchers aim to modulate the TME to enhance immune surveillance and improve patient outcomes. In this review article, we strive to summarize the composition of the tumor immune microenvironment, factors affecting the tumor immune microenvironment (TIME), and different therapeutic modalities targeting the immune cells. This review is a first-hand reference to understand the basics of immune surveillance and immune evasion.

Stereotactic radiotherapy for managing ovarian cancer oligoprogression under poly (ADP-ribose) polymerase inhibitors (PARPi)

OBJECTIVE

Poly (ADP-ribose) polymerase inhibitors (PARPi) have become a new standard of care for the maintenance treatment of advanced epithelial ovarian cancer. This study aims to evaluate the efficacy and safety of combining stereotactic body radiotherapy with PARPi continuation as a strategy to treat ovarian cancer oligoprogression on PARPi.

METHODS

This is a multicenter retrospective study including ovarian cancer patients treated with stereotactic body radiotherapy and PARPi continuation for oligoprogression under PARPi maintenance therapy between June 2012 and May 2023 in three Italian centers. PARPi treatment was continued until further disease progression or unacceptable toxicity. The primary endpoint was the next-line systemic therapy-free interval. The Kaplan-Meier method was used to assess local control, progression-free survival, and overall survival. Univariate and multivariate Cox regression analyses were performed to evaluate potential clinical outcomes predictors.

RESULTS

46 patients were included, with a total of 89 lesions treated over 63 radiotherapy treatments. Lymph nodes were the most frequently treated lesions (80, 89.9%), followed by visceral lesions (8, 9%) and one case with a bone lesion (1.1%). Median follow-up was 25.9 months (range 2.8-122). The median next-line systemic therapy-free interval was 12.4 months (95% CI 8.3 to 19.5). A number of prior chemotherapy lines greater than five was significantly associated with a reduced next-line systemic therapy-free interval (HR 3.21, 95% CI 1.11 to 9.32, p=0.032). At the time of analysis, 32 (69.6%) patients started a new systemic therapy regimen, while 14 (30.4%) remained on the PARPi regimen. The 2-year progression-free survival, local failure-free survival, and overall survival rates were 10.7%, 78.1%, and 76.5%, respectively. Four patients (8.7%) experienced acute toxicity with G1 gastrointestinal events.

CONCLUSION

Stereotactic body radiotherapy combined with PARPi continuation may be an effective and safe strategy for managing ovarian cancer patients with oligoprogression on PARPi maintenance therapy. Prospective research is warranted to shed more light on this approach.

Evaluation of the clinical efficacy of Ru'ai Shuhou recipe for the prevention of lung metastases from breast cancer: a retrospective study based on propensity score matching

Background

Breast cancer lung metastasis occurs at a high rate and at an early stage, and is the leading cause of death in breast cancer patients. The aim of this study was to investigate the effect of Ru'ai Shuhou Recipe (RSR) intervention on the occurrence of recurrent metastases, especially lung metastases, in postoperative patients with breast cancer.

Materials and Methods

A retrospective cohort study was implemented at Shuguang Hospital of Shanghai University of Traditional Chinese Medicine in China between January 2014 to January 2019. Female patients were included according to the propensity score matching (PSM) method and balanced on the basis of general and clinical information such as age, body mass index, neo-adjuvant therapy, and surgical approach. Patients with pathological diagnosis of breast cancer were included in this study. Breast cancer patients were divided into exposed and non-exposed groups according to whether they took RSR-based botanical drugs after surgery. Kaplan-Meier survival analysis and Cox survival analysis to explore the relationship between RSR and 5-year disease-free survival and incidence of lung metastases in breast cancer patients after surgery.

Results

360 female patients were assessed and 190 patients were included in the study after PSM (95 in each of the exposed and non-exposed groups). Of the 190 patients after PSM, 55.79% were over 50 years of age. The mean follow-up time was 60.55 ± 14.82 months in the exposed group and 57.12 ± 16.37 months in the non-exposed group. There was no significant baseline characteristics difference between two groups. Kaplan-Meier analysis showed that the 5-year incidence of lung metastases was significantly lower in the exposed group, and the disease-free survival of patients was significantly longer. Cox univariate and multivariate analysis showed that neoadjuvant chemotherapy and lymph node metastasis were independent risk factors for the development of breast cancer lung metastasis, with risk ratios of 17.188 and 5.812, while RSR treatment was an independent protective factor against the development of breast cancer lung metastasis, with a risk ratio of 0.290.

Conclusion

Standard biomedical treatment combined with RSR intervention can better prevent breast cancer recurrence and metastasis, reduce the incidence of lung metastasis in patients, and improve long-term prognosis.

The Landscape of Stereotactic Ablative Radiotherapy (SABR) for Renal Cell Cancer (RCC)

Renal cell cancer (RCC) has traditionally been considered radioresistant. Because of this, conventional radiotherapy (RT) has been predominantly relegated to the palliation of symptomatic metastatic disease. The implementation of stereotactic ablative radiotherapy (SABR) has made it possible to deliver higher ablative doses safely, shifting the renal radioresistance paradigm. SABR has increasingly been adopted into the multidisciplinary framework for the treatment of locally recurrent, oligoprogressive, and oligometastatic disease. Furthermore, there is growing evidence of SABR as a non-invasive definitive therapy in patients with primary RCC who are medically inoperable or who decline surgery, unsuited to invasive ablation (surgery or percutaneous techniques), or at high-risk of requiring post-operative dialysis. Encouraging outcomes have even been reported in cases of solitary kidney or pre-existing chronic disease (poor eGFR), with a high likelihood of preserving renal function. A review of clinical evidence supporting the use of ablative radiotherapy (SABR) in primary, recurrent, and metastatic RCC has been conducted. Given the potential immunogenic effect of the high RT doses, we also explore emerging opportunities to combine SABR with systemic treatments. In addition, we explore future directions and ongoing clinical trials in the evolving landscape of this disease.

High-intensity focused ultrasound ablation combined with immunotherapy for treating liver metastases: A prospective non-randomized trial

PURPOSE

Given the unique features of the liver, it is necessary to combine immunotherapy with other therapies to improve its efficacy in patients of advanced cancer with liver metastases (LM). High-intensity focused ultrasound (HIFU) ablation is now widely used in clinical practice and can enhanced immune benefits. The study is intended to prospectively evaluate the safety and clinical feasibility of HIFU ablation in combination with systemic immunotherapy for patients with liver metastases.

METHODS

The study enrolled 14 patients with LM who received ultrasound-guided HIFU ablation combined with immune checkpoint inhibitors (ICIs) such as anti-programmed cell death protein 1 (anti-PD-1 agents manufactured in China) at Mianyang Central Hospital. Patients were followed up for adverse events (AEs) during the trial, using the CommonTerminology Criteria for Adverse Events v5.0(CTCAE v5.0) as the standard. Tumour response after treatment was assessed using computerized tomography.

RESULTS

The 14 patients (age range, 35-84 years) underwent HIFU ablation at 19 metastatic sites and systemic immunotherapy. The mean lesion volume was 179.9 cm3 (maximum: 733.1 cm3). Median follow-up for this trial was 9 months (range: 3-21) months. The study is clinically feasible and acceptable to patients.

CONCLUSION

This prospective study confirmed that HIFU combined with immunotherapy is clinically feasible and safe for treating liver metastases.

Beyond success: unveiling the hidden potential of radiotherapy and immunotherapy in solid tumors

Immunotherapy, particularly with immune checkpoint inhibitors, has significantly transformed cancer treatment. Despite its success, many patients struggle to respond adequately or sustain long-lasting clinical improvement. A growing consensus has emerged that radiotherapy (RT) enhances the response rate and overall efficacy of immunotherapy. Although combining RT and immunotherapy has been extensively investigated in preclinical models and has shown promising results, establishing itself as a dynamic and thriving area of research, clinical evidence for this combination strategy over the past five years has shown both positive and disappointing results, suggesting the need for a more nuanced understanding. This review provides a balanced and updated analysis of the combination of immunotherapy and RT. We summarized the preclinical mechanisms through which RT boosts antitumor immune responses and mainly focused on the outcomes of recently updated clinical trials, including those that may not have met expectations. We investigated the optimization of the therapeutic potential of this combined strategy, including key challenges, such as fractionation and scheduling, lymph node irradiation, and toxicity. Finally, we offered insights into the prospects and challenges associated with the clinical translation of this combination therapy, providing a realistic perspective on the current state of research and potential future directions.

Systematic review of the efficacy of stereotactic ablative radiotherapy for oligoprogressive disease in metastatic cancer

BACKGROUND

Stereotactic Ablative Radiotherapy (SABR) for the treatment of oligometastatic disease can improve survival and delay the requirement for systemic therapy. The benefits of SABR in oligoprogressive disease are less well-defined. Here, we evaluate the available evidence investigating the efficacy of SABR in the treatment of oligoprogressive disease.

METHODS

A systematic review was carried out following PRISMA guidelines. Medline and Embase databases were searched using the terms "stereotactic radiotherapy" OR "SABR" OR "Stereotactic Ablative Body Radiotherapy" OR "SBRT" OR "SRT" AND "oligoprogression" in May 2022, June 2023, and February 2024. Studies were excluded where: SABR was used as a radical treatment, a specific oligoprogressive cohort could not be identified, publication was as a conference abstract or where fewer than 10 patients were recruited. Studies treating only brain metastases were also excluded. The site of primary tumour, oligoprogressive sites, rates of overall survival (OS), progression free survival (PFS), local control (LC) and time to next systemic therapy were collected.

RESULTS

Thirty-three full text studies were included. These consisted of single centre and multi-institutional observational studies, case series and phase II trials. Twenty-two studies were related to a specific tumour type: 12 urological cancer (9 prostate, 3 renal cancer), 6 non-small cell lung cancer, 2 colorectal cancer, 2 breast cancer and 11 were studies covering multiple tumour sites (5 studies involving SABR to a single organ and 6 studies involving SABR to multi-organ). Median PFS was >6 months in patients with oligoprogressive prostate, non-small cell lung cancer and renal cancer patients.

CONCLUSIONS

SABR appears to have clinical benefit in oligoprogresssive prostate, lung, and renal patients. However, the optimal management of patients with oligoprogressive disease is still somewhat uncertain due to lack of prospective data. This will hopefully become clearer in the near future with the publication of further randomised trials.

Exploiting cell death and tumor immunity in cancer therapy: challenges and future directions

Cancer remains a significant global challenge, with escalating incidence rates and a substantial burden on healthcare systems worldwide. Herein, we present an in-depth exploration of the intricate interplay between cancer cell death pathways and tumor immunity within the tumor microenvironment (TME). We begin by elucidating the epidemiological landscape of cancer, highlighting its pervasive impact on premature mortality and the pronounced burden in regions such as Asia and Africa. Our analysis centers on the pivotal concept of immunogenic cell death (ICD), whereby cancer cells succumbing to specific stimuli undergo a transformation that elicits robust anti-tumor immune responses. We scrutinize the mechanisms underpinning ICD induction, emphasizing the release of damage-associated molecular patterns (DAMPs) and tumor-associated antigens (TAAs) as key triggers for dendritic cell (DC) activation and subsequent T cell priming. Moreover, we explore the contributions of non-apoptotic RCD pathways, including necroptosis, ferroptosis, and pyroptosis, to tumor immunity within the TME. Emerging evidence suggests that these alternative cell death modalities possess immunogenic properties and can synergize with conventional treatments to bolster anti-tumor immune responses. Furthermore, we discuss the therapeutic implications of targeting the TME for cancer treatment, highlighting strategies to harness immunogenic cell death and manipulate non-apoptotic cell death pathways for therapeutic benefit. By elucidating the intricate crosstalk between cancer cell death and immune modulation within the TME, this review aims to pave the way for the development of novel cancer therapies that exploit the interplay between cell death mechanisms and tumor immunity and overcome Challenges in the Development and implementation of Novel Therapies.