Combination of stereotactic radiotherapy and targeted therapy: patterns-of-care survey in German-speaking countries

Engineered exosomes from different sources for cancer-targeted therapy

Exosome is a subgroup of extracellular vesicles, which has been serving as an efficient therapeutic tool for various diseases. Engineered exosomes are the sort of exosomes modified with surface decoration and internal therapeutic molecules. After appropriate modification, engineered exosomes are able to deliver antitumor drugs to tumor sites efficiently and precisely with fewer treatment-related adverse effects. However, there still exist many challenges for the clinical translation of engineered exosomes. For instance, what sources and modification strategies could endow exosomes with the most efficient antitumor activity is still poorly understood. Additionally, how to choose appropriately engineered exosomes in different antitumor therapies is another unresolved problem. In this review, we summarized the characteristics of engineered exosomes, especially the spatial and temporal properties. Additionally, we concluded the recent advances in engineered exosomes in the cancer fields, including the sources, isolation technologies, modification strategies, and labeling and imaging methods of engineered exosomes. Furthermore, the applications of engineered exosomes in different antitumor therapies were summarized, such as photodynamic therapy, gene therapy, and immunotherapy. Consequently, the above provides the cancer researchers in this community with the latest ideas on engineered exosome modification and new direction of new drug development, which is prospective to accelerate the clinical translation of engineered exosomes for cancer-targeted therapy.

Oligometastasis in breast cancer—current status and treatment options from a radiation oncology perspective

Evidence from a few small randomized trials and retrospective cohorts mostly including various tumor entities indicates a prolongation of disease free survival (DFS) and overall survival (OS) from local ablative therapies in oligometastatic disease (OMD). However, it is still unclear which patients benefit most from this approach. We give an overview of the several aspects of stereotactic body radiotherapy (SBRT) in extracranial OMD in breast cancer from a radiation oncology perspective. A PubMed search referring to this was conducted. An attempt was made to relate the therapeutic efficacy of SBRT to various prognostic factors. Data from approximately 500 breast cancer patients treated with SBRT for OMD in mostly in small cohort studies have been published, consistently indicating high local tumor control rates and favorable progression-free (PFS) and overall survival (OS). Predictors for a good prognosis after SBRT are favorable biological subtype (hormone receptor positive, HER2 negative), solitary metastasis, bone-only metastasis, and long metastasis-free interval. However, definitive proof that SBRT in OMD breast cancer prolongs DFS or OS is lacking, since, with the exception of one small randomized trial (n = 22 in the SBRT arm), none of the cohort studies had an adequate control group. Further studies are needed to prove the benefit of SBRT in OMD breast cancer and to define adequate selection criteria. Currently, the use of local ablative SBRT should always be discussed in a multidisciplinary tumor board.

Stereotactic Body Radiotherapy of adrenal metastases - A dose-finding study

Optimal doses for the treatment of adrenal metastases with stereotactic radiotherapy (SBRT) are unknown. We aimed to identify dose-volume cut-points associated with decreased local recurrence rates (LRR). A multicenter database of patients with adrenal metastases of any histology treated with SBRT (biologically effective dose, BED10 ≥ 50Gy, ≤ 12 fractions) was analyzed. Details on dose-volume parameters were required (planning target volume: PTV-D98%, PTV-D50%, PTV-D2%; gross tumor volume: GTV-D50%, GTV-mean). Cut-points for LRR were optimized using the R maxstat package. 196 patients with 218 lesions were included, the largest histopathological subgroup was adenocarcinoma (n = 101). Cut-point optimization resulted in significant cut-points for PTV-D50% (BED10: 73.2Gy; p = 0.003), GTV-D50% (BED10: 74.2Gy; p = 0.006), GTV-mean (BED10: 73.0Gy; p = 0.007), and PTV-D2% (BED10: 78.0Gy; p = 0.02) but not for the PTV-D98% (p = 0.06). Differences in LRR were clinically relevant (LRR ≥ doubled for cut-points that were not achieved). Further dose-escalation was not associated with further improved LRR. PTV-D50%, GTV-D50%, and GTV-mean cut-points were also associated with significantly improved LRR in the adenocarcinoma subgroup. Separate dose optimizations indicated a lower cut-point for the PTV-D50% (BED10: 69.1Gy) in adenocarcinoma lesions, other values were similar (< 2% difference). Associations of cut-points with overall survival (OS) and progression-free survival were not significant but durable freedom from local recurrence was associated with OS in a landmark model (p < 0.001). To achieve a significant improvement of LRR for adrenal SBRT, a moderate escalation of PTV-D50% BED10 > 73.2Gy (adenocarcinoma: 69.1Gy) should be considered. This article is protected by copyright. All rights reserved.

Hypofractionated radiotherapy combined with targeted therapy or immunotherapy: Dutch survey on current practice, knowledge and challenges

•

Radiotherapy referral during targeted therapy or immunotherapy occurs regularly.

•

There is a knowledge gap regarding the implications of combined therapy.

•

There is no consensus on expected toxicity of combined therapy.

•

Multidisciplinary protocols regarding combined therapy are often not available.

•

The application of radiotherapy treatment adaptations varies widely when combined with different systemic treatments.

Introduction

With the introduction of tyrosine kinase inhibitors and systemic antibodies, including immune checkpoint inhibitors, the survival of advanced-stage cancer patients has improved for many tumor types. These patients are increasingly referred for radiotherapy, but it is unclear whether radiotherapy combined with these drugs is safe. No international guidelines exist on whether or how to combine these drugs with radiotherapy. Therefore, we investigated the current clinical practice in the Netherlands regarding hypofractionated radiotherapy in patients using targeted drugs and immunotherapy.

Materials and methods

We sent a survey to all 21 Dutch radiotherapy institutes. Dedicated radiation oncologists, medical oncologists and pulmonologists were asked to fill out the survey. The questions explored their familiarity with the combination of targeted drugs and immunotherapy with radiotherapy, the encountered clinical difficulties and factors influencing treatment decisions.

Results

The survey was filled out by 54 respondents from 19 different institutes. The median annual number of patients per radiation oncologist referred for radiotherapy when using targeted drugs or immunotherapy was 10 and 15, respectively. Despite this high number, only 11% of the radiation oncologists stated that they had sufficient information (resources) for adequate treatment decision making. Among all physicians, 44% stated that there was insufficient knowledge within their institute regarding this topic. Only 17% stated that there was a multidisciplinary protocol available. The application of radiotherapy treatment adaptations (technique, dose, fractionation, field size) varied widely. Generally, there seemed to be no consensus regarding the expected toxicity of combined drug-radiotherapy treatments and the expected risk of tumor flare upon temporary drug discontinuation.

Conclusion

There is no consensus amongst involved medical specialties on expected toxicity. Consequently, it is necessary to perform clinical studies examining the safety of combined drug-radiotherapy treatments, to add radiotherapy to phase I-III clinical trials for new drugs and to incorporate outcomes into multidisciplinary, evidence-based guidelines.

Continued versus Interrupted Targeted Therapy during Metastasis-Directed Stereotactic Radiotherapy: A Retrospective Multi-Center Safety and Efficacy Analysis

Simple Summary

The increasing use of targeted therapy (TT) has resulted in prolonged disease control and survival in many metastatic cancers. In parallel, stereotactic radiotherapy (SRT) is increasingly performed in patients receiving TT to obtain a durable control of resistant metastases, and thereby to prolong the time to disseminated disease progression and switch of systemic therapy. The aim of this study was to analyze the safety and efficacy of SRT combined with TT in metastatic cancer patients and to assess the influence of continuous vs. interrupted TT during metastasis-directed SRT. The data of 454 SRTs in 158 patients from the international multicenter database (TOaSTT) on metastatic cancer patients treated with SRT and concurrent TT (within 30 days) were analyzed. We found that there was no significant difference in survival, progression, or severe toxicity, whether TT was interrupted during SRT or not. Although any-grade acute and late SRT-related toxicity occurred in 63 (40%) and 52 (33%) patients, severe SRT-related toxicity rates were low (3% and 4%, respectively). The highest toxicity rates were observed for the combination of SRT and EGFRi or BRAF/MEKi, and any grade of toxicity was significantly increased when EGFRi or BRAF/MEKi were continued during SRT. However, this did not account for severe toxicity.

Abstract

The increasing use of targeted therapy (TT) has resulted in prolonged disease control and survival in many metastatic cancers. In parallel, stereotactic radiotherapy (SRT) is increasingly performed in patients receiving TT to obtain a durable control of resistant metastases, and thereby to prolong the time to disseminated disease progression and switch of systemic therapy. The aims of this study were to analyze the safety and efficacy of SRT combined with TT in metastatic cancer patients and to assess the influence of continuous vs. interrupted TT during metastasis-directed SRT. The data of 454 SRTs in 158 patients from the international multicenter database (TOaSTT) on metastatic cancer patients treated with SRT and concurrent TT (within 30 days) were analyzed using Kaplan–Meier and log rank testing. Toxicity was defined by the CTCAE v4.03 criteria. The median FU was 19.9 mo (range 1–102 mo); 1y OS, PFS and LC were 59%, 24% and 84%, respectively. Median TTS was 25.5 mo (95% CI 11–40). TT was started before SRT in 77% of patients. TT was interrupted during SRT in 44% of patients, with a median interruption of 7 (range 1–42) days. There was no significant difference in OS or PFS whether TT was temporarily interrupted during SRT or not. Any-grade acute and late SRT-related toxicity occurred in 63 (40%) and 52 (33%) patients, respectively. The highest toxicity rates were observed for the combination of SRT and EGFRi or BRAF/MEKi, and any-grade toxicity was significantly increased when EGFRi (p = 0.016) or BRAF/MEKi (p = 0.009) were continued during SRT. Severe (≥grade 3) acute and late SRT-related toxicity were observed in 5 (3%) and 7 (4%) patients, respectively, most frequently in patients treated with EGFRi or BRAF/MEKi and in the intracranial cohort. There was no significant difference in severe toxicity whether TT was interrupted before and after SRT or not. In conclusion, SRT and continuous vs. interrupted TT in metastatic cancer patients did not influence OS or PFS. Overall, severe toxicity of combined treatment was rare; a potentially increased toxicity after SRT and continuous treatment with EGFR inhibitors or BRAF(±MEK) inhibitors requires further evaluation.

Toxicity of combined targeted therapy and concurrent radiotherapy in metastatic melanoma patients: a single-center retrospective analysis

Supplemental Digital Content is available in the text.

The Eastern Cooperative Oncology Group consensus guidelines from 2016 recommend interruption of targeted therapy with BRAF- and MEK-inhibitors during radiotherapy with data being based mostly on BRAF monotherapy. The aim of this study is to provide data on the safety of concurrent radiotherapy and combination targeted therapy with BRAF- and MEK-inhibitors. A total of 32 patients with 51 sessions of radiotherapy from one center receiving concurrent radiotherapy and BRAF- and MEK- inhibitors were included. Radiotherapy-associated toxicities were retrospectively collected. Incidence was compared between three groups: (A) targeted therapy during radiotherapy with and, (B) without interruption, and (C) radiotherapy before the start of targeted therapy. Survival and local disease control were examined. Targeted therapy was interrupted during radiotherapy in 16, not interrupted in 14, and only started after radiotherapy in 21 sessions. Stereotactic radiotherapy was applied in 28 sessions, conventionally fractionated radiotherapy in 23. The brain was the most common site of irradiation (n = 36). Radiotherapy-associated toxicities occurred in 41.2% (n = 21) of sessions and did not differ significantly among the groups. Overall survival was 11.7 months and progression-free survival was 8.4 months. No increase in radiotherapy-associated toxicity was seen where combination targeted therapy was not interrupted during radiotherapy. Prospective clinical trials are warranted to support our findings.

Targeted therapy moves to earlier stages of non-small-cell lung cancer: emerging evidence, controversies and future challenges

Lung cancer continues to be the leading cause of cancer mortality and a serious health problem despite the numerous advances made in the last decade and the rapid advance of research in this field. In recent years, there has been a decrease in mortality from lung cancer coinciding with the approval times of targeted therapy. To date, targeted therapy has been used in the context of advanced disease in clinical practice, with great benefits in survival and quality of life. The next step will be to incorporate targeted therapy into the treatment of earlier stages of non-small-cell lung cancer, and there is already a randomized trial showing a disease-free survival benefit. However, there are many questions that need to be resolved first. In the present review, the authors discuss the findings of published reports and ongoing clinical trials assessing the role of targeted therapies in nonmetastatic disease.

A fatal wound complication following sequential anti-angiogenesis, immune checkpoint inhibition and ultra-hypofractionated radiotherapy

PURPOSE

Multimodality treatments combining radiotherapy, immune therapy and/or targeted therapy are under heavy investigation. Promising data from clinical trials are emerging, nevertheless unexpected interactions and adverse events should not be overlooked.

CASE PRESENTATION

Here we present a case study of a patient with metastatic colon adenocarcinoma treated sequentially with a chemotherapy/targeted therapy combination, immune checkpoint inhibitors and ultra-hypofractionated radiotherapy. After radiation treatment, the patient developed extensive posterior abdominal wall wounds coinciding with regression of the irradiated metastatic tumour mass and marked elevation of the inflammation parameters.

CONCLUSION

This case represents an unusual fatal wound complication after palliative ultra-hypofractionated radiotherapy. Further research into synergistic effects of sequential radiotherapy and anti-angiogenesis therapy may provide an advantage in anticipating severe sequelae.

Stereotactic or conformal radiotherapy for adrenal metastases: Patient characteristics and outcomes in a multicenter analysis

To report outcome (freedom from local progression [FFLP], overall survival [OS] and toxicity) after stereotactic, palliative or highly conformal fractionated (>12) radiotherapy (SBRT, Pall-RT, 3DCRT/IMRT) for adrenal metastases in a retrospective multicenter cohort within the framework of the German Society for Radiation Oncology (DEGRO). Adrenal metastases treated with SBRT (≤12 fractions, biologically effective dose [BED10] ≥ 50 Gy), 3DCRT/IMRT (>12 fractions, BED10 ≥ 50 Gy) or Pall-RT (BED10 < 50 Gy) were eligible for this analysis. In addition to unadjusted FFLP (Kaplan-Meier/log-rank), we calculated the competing-risk-adjusted local recurrence rate (CRA-LRR). Three hundred twenty-six patients with 366 metastases were included by 21 centers (median follow-up: 11.7 months). Treatment was SBRT, 3DCRT/IMRT and Pall-RT in 260, 27 and 79 cases, respectively. Most frequent primary tumors were non-small-cell lung cancer (NSCLC; 52.5%), SCLC (16.3%) and melanoma (6.7%). Unadjusted FFLP was higher after SBRT vs Pall-RT (P = .026) while numerical differences in CRA-LRR between groups did not reach statistical significance (1-year CRA-LRR: 13.8%, 17.4% and 27.7%). OS was longer after SBRT vs other groups (P < .05) and increased in patients with locally controlled metastases in a landmark analysis (P < .0001). Toxicity was mostly mild; notably, four cases of adrenal insufficiency occurred, two of which were likely caused by immunotherapy or tumor progression. Radiotherapy for adrenal metastases was associated with a mild toxicity profile in all groups and a favorable 1-year CRA-LRR after SBRT or 3DCRT/IMRT. One-year FFLP was associated with longer OS. Dose-response analyses for the dataset are underway.

Liver SBRT with active motion-compensation results in excellent local control for liver oligometastases: An outcome analysis of a pooled multi-platform patient cohort

BACKGROUND

Local treatment of metastases in combination with systemic therapy can prolong survival of oligo-metastasized patients. To fully exploit this potential, safe and effective treatments are needed to ensure long-term metastases control. Stereotactic body radiotherapy (SBRT) is one means, however, for moving liver tumors correct delivery of high doses is challenging. After validating equal in-vivo treatment accuracy, we analyzed a pooled multi-platform liver-SBRT-database for clinical outcome.

METHODS

Local control (LC), progression-free interval (PFI), overall survival (OS), predictive factors and toxicity was evaluated in 135 patients with 227 metastases treated by gantry-based SBRT (deep-inspiratory breath-hold-gating; n = 71) and robotic-based SBRT (fiducial-tracking, n = 156) with mean gross tumor volume biological effective dose (GTV-BED_α/β=10Gy) of 146.6 Gy₁₀.

RESULTS

One-, and five-year LC was 90% and 68.7%, respectively. On multivariate analysis, LC was significantly predicted by colorectal histology (p = 0.006). Median OS was 20 months with one- and two-year OS of 67% and 37%. On multivariate analysis, ECOG-status (p = 0.003), simultaneous chemotherapy (p = 0.003), time from metastasis detection to SBRT-treatment (≥2months; p = 0.021) and LC of the treated metastases (≥12 months, p < 0.009) were significant predictors for OS. One- and two-year PFI were 30.5% and 14%. Acute toxicity was mild and rare (14.4% grade I, 2.3% grade II, 0.6% grade III). Chronic °III/IV toxicities occurred in 1.1%.

CONCLUSIONS

Patient selection, time to treatment and sufficient doses are essential to achieve optimal outcome for SBRT with active motion compensation. Local control appears favorable compared to historical control. Long-term LC of the treated lesions was associated with longer overall survival.

Stereotactic Ablative Radiotherapy for the Management of Spinal Metastases: A Review

Importance

Rising cancer incidence combined with improvements in systemic and local therapies extending life expectancy are translating into more patients with spinal metastases. This makes the multidisciplinary management of spinal metastases and development of new therapies increasingly important. Spinal metastases may cause significant pain and reduced quality of life and lead to permanent neurological disability if compression of the spinal cord and/or nerve root occurs. Until recently, treatments for spinal metastases were not optimal and provided temporary local control and pain relief. Spinal stereotactic ablative radiotherapy (SABR) is an effective approach associated with an improved therapeutic ratio, with evolving clinical application.

Objective

To review the literature of spinal SABR for spinal metastases, discuss a multidisciplinary approach to appropriate patient selection and technical considerations, and summarize current efforts to combine spinal SABR with systemic therapies.

Evidence Review

The MEDLINE database was searched to identify articles reporting on spinal SABR to September 30, 2018. Articles including clinical trials, prospective and retrospective studies, systematic reviews, and consensus recommendations were selected for relevance to multidisciplinary management of spinal metastases.

Results

Fifty-nine unique publications with 5655 patients who underwent SABR for spinal metastases were included. Four comprehensive frameworks for patient selection were discussed. Spinal SABR was associated with 1-year local control rates of approximately 80% to 90% in the de novo setting, greater than 80% in the postoperative setting, and greater than 65% in the reirradiation setting. The most commonly discussed adverse effect was development of a vertebral compression fracture with variable rates, most commonly reported as approximately 10% to 15%. High-level data on the combination of SABR with modern therapies are still lacking. At present, 19 clinical trials are ongoing, mainly focusing on combined modality therapies, radiotherapy prescription dose, and oligometastic disease.

Conclusions and Relevance

These findings suggest that spinal SABR may be an effective treatment option for well-selected patients with spinal metastases, achieving high rates of local tumor control with moderate rates of adverse effects. Optimal management should include review by a multidisciplinary care team.

Radiation-induced damage in the upper gastrointestinal tract: clinical presentation, diagnostic tests and treatment options

Radiation-induced damage of the upper gastrointestinal (GI) tract results from radiation of GI tumors or structures adjacent to the GI tract. Radiation-induced damages of the upper GI tract may be acute or delayed, and ranges from lack of appetite, mucosal inflammation (i.e. esophagitis, gastritis, duodenitis) to ulcers, which may be complicated by perforation, penetration, bleeding and stenosis. Radiation-related factors as well as individual patient predisposing factors may increase susceptibility to post-radiation damage. High quality evidence for the treatment of radiation-induced GI damage is scarce and the management is often extrapolated from studies on GI lesions of different etiology. Treatment depends on severity and localization of the radiation-induced damage, and ranges from supportive and dietary measures to endoscopic interventions or surgery. Modern radiation techniques may decrease the incidence and severity of the radiation-induced upper gastrointestinal disease.

Prospective Evaluation of All-lesion Versus Single-lesion Radiotherapy in Combination With PD-1/PD-L1 Immune Checkpoint Inhibitors

Background

Local ablative treatments improve survival in patients with oligometastatic disease in addition to chemotherapy. The application of immune checkpoint inhibitors prolonged patients’ survival in different tumor entities. This raises the question if patients still benefit from intensified local treatments in combination with a more efficient systemic treatment with immune checkpoint inhibitors.

Methods

The prospective non-interventional ST-ICI trial investigates treatment with PD-1/PD-L1 (Programmed cell death protein 1/Programmed cell death 1 ligand 1) immune checkpoint inhibitors and radiotherapy in different tumor entities. Patients who started radiotherapy and immunotherapy concomitantly were included in this interim analysis. In this cohort patients with all-lesion radiotherapy (all tumor lesions irradiated, al-RT) were compared to patients with radiotherapy to only a single of their tumor lesions (single-lesion radiotherapy, sl-RT). Endpoints of the interim analysis were progression-free survival (PFS), overall survival (OS) and time to progression (TTP).

Results

A total of 104 patients were registered between April 2017 and August 2019. Fifty patients started immune checkpoint inhibitor treatment and radiotherapy concomitantly and were included. Most frequent tumor entities were non-small cell lung cancer (62%) followed by head and neck squamous cell cancer (26%). Most frequent location of radiotherapy was lung (34%) and central nervous system (20%). Median duration of follow-up was 8.6 months beginning with first administration of the immune-checkpoint-inhibitor. Median PFS was 9.2 months (95% CI, 5.8 – 12.6) in the al-RT group and 3.0 months (95% CI, 2.5 – 3.5) in the sl-RT group (p<0.001). Median OS was 11.6 months (95% CI, 8.1 - 15.1) in the al-RT group and 4.2 months (95% CI, 3.0 - 5.4) in the sl-RT group (p=0.007). Median TTP was not reached in the al-RT group compared to 4.6 months (95% CI, 1.1–8.0) in the sl-RT group (p=0.028). Univariate Cox regression analyses computed tumor entity, histology, central nervous system metastases, immunotherapy drug and al-RT as predictors of OS (with an effect p-value of ≤ 0.1). In the multivariable analysis only tumor entity and al-RT remained prognostic factors for OS.

Conclusion

Patients with PD-1/PD-L1 immune checkpoint inhibitor therapy benefit from local radiotherapy to all known lesions compared to single-lesion radiotherapy regarding PFS and OS.

PARP inhibitors combined with ionizing radiation induce different effects in melanoma cells and healthy fibroblasts

Background

PARP inhibitors niraparib and talazoparib are FDA approved for special cases of breast cancer. PARP is an interesting repair protein which is frequently affected in cancer cells. We studied the combined action of talazoparib or niraparib with ionizing radiation in melanoma cells and healthy fibroblasts.

Methods

Homologous recombination (HR) status in six different melanoma cell lines and healthy fibroblasts was assessed. Cell cultures were treated with PARP inhibitors talazoparib or niraparib and ionizing radiation (IR). Apoptosis, necrosis and cell cycle distribution was analyzed via flow cytometry. Cell migration was studied by scratch assays.

Results

Studied melanoma cell cultures are HR deficient. Studied healthy fibroblasts are HR proficient. Talazoparib and niraparib have congruent effects within the same cell cultures. In all cell cultures, combined treatment increases cell death and G2/M arrest compared to IR. Combined treatment in melanoma cells distinctly increases G2/M arrest. Healthy fibroblasts are less affected by G2/M arrest. Treatment predominantly decelerates or does not modify migration. In two cell cultures migration is enhanced under the inhibitors.

Conclusions

Although the two PARP inhibitors talazoparib and niraparib appear to be suitable for a combination treatment with ionizing radiation in our in vitro studies, a combination treatment cannot generally be recommended. There are clear interindividual differences in the effect of the inhibitors on different melanoma cells. Therefore, the effect on the cancer cells should be studied prior to a combination therapy. Since melanoma cells increase more strongly than fibroblasts in G2/M arrest, the fractional application of combined treatment should be further investigated.

Impact of preoperative treatment on the CINSARC prognostic signature: translational research results from a phase 1 trial of the German Interdisciplinary Sarcoma Group (GISG 03)

PURPOSE

CINSARC (Complexity INdex in SARComas) is a prognostic signature for soft tissue sarcoma that determines the risk for recurrence and may serve to guide the decision for adjuvant chemotherapy. The aim of this study was to compare the CINSARC signature of pre- and posttreatment biopsies of sarcoma patients treated within a phase I trial evaluating preoperative sunitinib and irradiation.

METHODS

We retrieved 14 pairs of formalin-fixed paraffin-embedded blocks from pretreatment biopsies and posttreatment resection specimens and performed expression profiling of the 67 CINSARC signature genes.

RESULTS

In 5/14 patients, both probes were unsuitable for expression analysis because there was no (vital) tissue left in biopsies or resection specimens. Comparing the CINSARC risk classification before and after treatment in the remaining patients, 2/9 shifted from a high- to a low-risk classification for metastatic disease after preoperative treatment with radiation therapy plus sunitinib and 7/9 pairs of pre- and posttreatment biopsies revealed identical results.

CONCLUSION

Concurrent radiation therapy and sunitinib leads to diverging results of prognostic gene array testing in a relevant proportion of sarcoma patients. These changes may reflect tumor heterogeneity, local treatment effects, or prognostic changes of the disease. Caution is advised in the selection of samples and interpretation of test results.

Optimal Timing and Sequence of Immunotherapy When Combined with Stereotactic Radiosurgery in the Treatment of Brain Metastases

Checkpoint immunotherapy (CIT) is an emerging and exciting treatment modality for the treatment of cancer. Much excitement has ensued in the potential of CIT to revolutionize the treatment and prognosis of brain metastases. The combination of stereotactic radiosurgery (SRS) and CIT has also been studied and showed promise compared with either treatment modality alone. However, several questions have arisen, in particular, the timing at which SRS and CIT should be administered relative to each other. We reviewed the reported data and attempted to offer a potential answer to this question.