Stereotactic body radiation therapy (SBRT) for lung metastases from sarcoma in oligometastatic patients: a phase 2 study

Precision Treatment of Pulmonary Sarcoma Metastasis Using Personalized Ultrafractionated Stereotactic Adaptive Radiotherapy: A Case Report

The lungs represent the most common sites of distant metastases in soft tissue sarcoma (STS) patients. The relative radioresistance of STS renders them ideal targets for stereotactic radiotherapy (SRT). In this study, the treatment of a complex STS lung metastases case involving complete main bronchus occlusion and lung collapse using an image-guided, personalized ultrafractionated stereotactic adaptive radiotherapy (PULSAR) approach is reported. A biologically effective dose (BED) of 102 Gy10 was delivered in two stages separated by 21 days using the CyberKnifeTM platform (Accuray Inc., Sunnyvale, CA, USA) and the Synchrony Lung Optimized (Synchrony-LOTTM) motion management system (Accuray Inc.). Each treatment stage was based on real-time imaging data, allowing for the adaption of the treatment plan to the tumor's size and shape. Prior to the second stage, significant tumor regression was observed, leading to lung re-expansion and restoration of pulmonary function. This expansion enabled the visualization and treatment of a second peripheral lesion, which received a BED of 106 Gy10 in a single session. The applied treatment protocol resulted in excellent local control and minimal toxicity. The combination of the PULSAR approach and real-time imaging techniques hold significant promise for treating complex cases and marks a shift toward more adaptive and personalized radiation oncology.

Stereotactic ablative radiotherapy for pulmonary metastasis from sarcoma: a retrospective comparison with metastasectomy

Recent studies report excellent local control (LC) and favorable toxicities of stereotactic ablative radiotherapy (SABR) for pulmonary metastasis (PM) from sarcoma. This study compared the LC and survival of SABR and metastasectomy for sarcoma PM. We analyzed the LC rates of 54 PMs treated with SABR between 2008 and 2022. For survival analysis, we compared 14 patients who received SABR as first-line treatment with 61 patients who underwent metastatectomy. For SABR-treated PMs, a median total dose of 55 Gy (range, 48-60) was administered over 3-10 fractions. Median follow-up for LC in SABR-treated PMs was 19.2 months (range, 0.8-124.0), and the 2-year LC rate was 92.2%. No patients experienced toxicities of grade 3 or higher. The median age of the patients in the survival analysis was 73 years (range, 42-83) in the SABR group and 54 years (range, 19-78) in the metastasectomy group (p < 0.001). PMs in the "gray zone" were more common in the SABR group (35.7%) than in the metastasectomy group (8.2%) (p = 0.029). The median follow-up for survival analysis was 44.8 months (interquartile range, 21.5-66.4). The 3-year rates of LC and overall survival were 92.3% and 57.3% in the SABR group and 89.2% and 75.9% in the metastasectomy group (p = 0.807, 0.224), respectively. The out-of-field intrapulmonary failure-free survival and extrapulmonary systemic failure-free survival rates at 3 years were not significantly different (p = 0.673, 0.386). SABR for sarcoma PM demonstrated excellent LC with acceptable toxicity. Survival rates of SABR were comparable to those of metastasectomy.

Unraveling the role of local ablative therapies for patients with metastatic soft tissue sarcoma - A retrospective multicenter study of the Bavarian university hospitals

BACKGROUND

Local ablative therapies (LAT) are increasingly used in patients with metastatic soft tissue sarcoma (STS), yet evidence-based standards are lacking. This study aimed to assess the impact of LAT on survival of metastatic STS patients and to identify prognostic factors.

METHODS

In this retrospective multicenter study, 246 STS patients with metastatic disease who underwent LAT on tumor board recommendation between 2017 and 2021 were analyzed. A mixed effects model was applied to evaluate multiple survival events per patient.

RESULTS

Median overall survival (OS) after first metastasis was 5.4 years with 1-, 2- and 5-year survival rates of 93.7, 81.7, and 53.1 %, respectively. A treatment-free interval ≥12 months and treatment of liver metastases were positively correlated with progression-free survival (PFS) after LAT (HR = 0.61, p = 0.00032 and HR = 0.52, p = 0.0081, respectively). A treatment-free interval ≥12 months and treatment of metastatic lesions in a single organ site other than lung and liver were positive prognostic factors for OS after first LAT (HR = 0.50, p = 0.028 and HR = 0.40, p = 0.026, respectively) while rare histotypes and LAT other than surgery and radiotherapy were negatively associated with OS after first LAT (HR = 2.56, p = 0.020 and HR = 3.87, p = 0.025). Additional systemic therapy was independently associated with a PFS benefit in patients ≤60 years with ≥4 metastatic lesions (for max. diameter of treated lesions ≤2 cm: HR = 0.32, p = 0.02 and >2 cm: HR = 0.20, p = 0.0011, respectively).

CONCLUSION

This multicenter study conducted at six German university hospitals underlines the value of LAT in metastatic STS. The exceptionally high survival rates are likely to be associated with patient selection and treatment in specialized sarcoma centers.

The Landmark Series: Multimodal Management of Oligometastatic Sarcoma

The concept of "oligometastatic" disease suggests the presence of intermediate states between localized disease and widespread metastases, which may be potentially treatable with curative therapeutic strategies. Metastases local therapy (MLT) can be accomplished through various techniques such as stereotactic ablative radiotherapy (SABR), radiofrequency ablation (RFA), microwave ablation (MWA), cryoablation, or surgical metastasectomy. The incorporation of MLT in the multidisciplinary treatment of patients with metastatic sarcoma is complex. Retrospective studies support consideration of MLT for selected patients based on factors such as patient condition, disease biology, histologic type, and disease burden. Decisions regarding type and timing of MLT should be made after multidisciplinary discussion including radiation oncologists, surgical and orthopedic oncologists, medical oncologists, and interventional radiology to explore all options before treatment decsions. All MLT techniques have advantages and disadvantages and should be performed in centers specialized in the care of complex oncology patients where various options can be explored concurrently or sequentially for each patient. Future studies evaluating quality of life and patient-reported outcomes are necessary to adequately align patient goals and optimal outcomes. This article reviews the medical scenarios that may benefit the use of MLT, evaluates the distinct advantages and disadvantages associated with these various techniques, and analyzes the findings from pivotal series to provide a comprehensive understanding of its role in clinical practice.

The Critical Role of Stereotactic Body Radiation Therapy in Multimodal Treatment of Lung Metastasis from Bone and Soft Tissue Sarcomas

BACKGROUND

Stereotactic body radiotherapy (SBRT) is increasingly used to treat lung metastasis (LM) in patients with soft tissue sarcoma (STS) and bone sarcoma (BS).

METHODS

This retrospective study evaluated the outcomes of patients with BS and STS treated with SBRT for LM between 2010 and 2023.

RESULTS

We enrolled 102 patients (51 each with STS and BS), of whom 71 were males and 31 were females (median age, 40 years; range, 11-81 years). At diagnosis, 76 and 26 patients had localized and metastatic disease, respectively, with a median of 4 recurrences (range, 1-12). Before SBRT, 75 patients received chemotherapy and 52 underwent surgery for LM, with 276 nodules treated with SBRT (median dose, 48 Gy; range, 40-52). Local control of irradiated LM was 86% at 1 year and 78% at 2 years. By 31 December 2023 (median follow-up, 4.8 years), 60 patients had died and 42 survived (20 without ongoing disease). From the first LM relapse, the median overall survival (OS) was 4.8 years and the 5-year OS was 49% (95% confidence interval, 39-60%), with no difference between STS and BS; the median OS was 2.9 years and the 5-year OS was 36% after SBRT. Chemotherapy before SBRT was a negative prognostic factor by multivariate analysis.

CONCLUSIONS

Long-term follow-up shows that SBRT as part of a multimodal treatment approach has reasonable survival rates in patients with LM due to sarcoma. Compared with historical results using only surgery and chemotherapy, SBRT has improved the 5-year OS.

Intra- and inter-fractional variations of tumors with fiducial markers measured using respiratory-correlated computed tomography images for respiratory gated lung stereotactic body radiation therapy

PURPOSE

This study evaluated the intra- and inter-fractional variation of tumors with fiducial markers (FMs), relative to the tumor-FM distance, to establish how close an FM should be inserted for respiratory-gated stereotactic body radiation therapy (RG-SBRT).

METHODS

Forty-five lung tumors treated with RG-SBRT were enrolled. End-expiratory computed tomography (CT) (CTplan) and four-dimensional-CT (4D-CT) scans were obtained for planning. End-expiratory CT (CTfr) scanning was performed before each fraction. The FMs were divided into two groups based on the median tumor-FM distance in the CTplan (Dp). For the intra-fractional variation, the correlations between the corresponding tumor and FM intra-fractional motions, defined as the centroid coordinates of those in each 0-90% phase, with the 50% phase of 4D-CT as the origin, were calculated in the left-right, anterior-posterior, and superior-inferior directions. Furthermore, the maximum difference in the tumor-FM distance in each phase of 4D-CT scan, based on those in the 50% phase of 4D-CT scan (Dmax), was obtained. Inter-fractional variation was defined as the maximum distance between the tumors in CTplan and CTfr, when the CT scans were fused based on each FM or vertebra.

RESULTS

The median Dp was 26.1 mm. While FM intra-fractional motions were significantly and strongly correlated with the tumor intra-fractional motions in only anterior-posterior and superior-inferior directions for the Dp > 26 mm group, they were significantly and strongly correlated in all directions for the Dp ≤ 26 mm group. In all directions, Dmax values of the Dp ≤ 26 mm group were lower than those of the Dp > 26 mm group. The inter-fractional variations based on the Dp ≤ 26 mm were smaller than those on the Dp > 26 mm and on the vertebra in all directions.

CONCLUSIONS

Regarding intra- and inter-fractional variation, FMs for Dp ≤ 26 mm can increase the accuracy for RG-SBRT.

SABR for Sarcoma Lung Metastases: Indications for Treatment and Guidance for Patient Selection

PURPOSE

The lungs are the most common site of metastasis for patients with soft tissue sarcoma. SABR is commonly employed to treat lung metastases among select patients with sarcoma with limited disease burden. We sought to evaluate outcomes and patterns of failure among patients with sarcoma treated with SABR for their lung metastases.

METHODS AND MATERIALS

We performed a retrospective review of patients treated at a tertiary cancer center between 2006 and 2020. Patient disease status at the time of SABR was categorized as either oligorecurrent or oligoprogressive. The Kaplan-Meier method was used to estimate disease outcomes. Uni- and multivariable analyses were conducted using the Cox proportional hazards model.

RESULTS

We identified 70 patients with soft tissue sarcoma treated with SABR to 98 metastatic lung lesions. Local recurrence-free survival after SABR treatment was 83% at 2 years. On univariable analysis, receipt of comprehensive SABR to all sites of pulmonary metastatic disease at the time of treatment was associated with improved progression-free survival (PFS; hazard ratio [HR], 0.51 [0.29-0.88]; P = .02). On multivariable analysis, only having systemic disease controlled at the time of SABR predicted improved PFS (median PFS, 14 vs 4 months; HR, 0.37 [0.20-0.69]; P = .002) and overall survival (median overall survival, 51 vs 14 months; HR, 0.17 [0.08-0.35]; P < .0001).

CONCLUSIONS

SABR provides durable long-term local control for sarcoma lung metastases. The most important predictor for improved outcomes was systemic disease control. Careful consideration of these factors should help guide decisions in a multidisciplinary setting to appropriately select the optimal candidates for SABR.

Oligometastatic sarcoma treated with Curative intent Ablative Radiotherapy (OSCAR): A multicenter study on behalf of AIRO (Italian association of Radiotherapy and clinical Oncology)

BACKGROUND AND PURPOSE

Stereotactic Ablative Radiotherapy (SABR) is emerging as a valid alternative to surgery in the oligometastatic setting in soft tissue sarcomas (STS), although robust data are lacking. The aim of this study is to evaluate toxicity and efficacy of SABR in oligometastatic STS.

MATERIALS AND METHODS

This is a retrospective multicenter study including adult patients affected by stage IV STS, treated with SABR for a maximum of 5 cranial or extracranial metastases in up to 3 different organs. SABR was delivered with ablative purposes. Study endpoints were overall survival (OS), local control (LC), distant progression free survival (DPFS), time to polymetastatic progression (TTPP), time to new systemic therapy (TTNS) and toxicity.

RESULTS

From 10 Italian RT centers, 138 patients (202 metastases) treated between 2010 and 2022 were enrolled in the study. Treatment was generally well tolerated, no acute or late toxicity ≥ G3 was recorded. Median follow up was 42.5 months. Median OS was 39.7 months. Actuarial OS at 1 and 2 years was 91.5 % and 72.7 %. Actuarial LC at 1 and 2 years was 94.8 % and 88.0 %. Median DPFS was 9.7 months. Actuarial DPFS at 1 and 2 years was 40.8 % and 19.4 %.

CONCLUSION

SABR is a safe and effective approach for the treatment of oligometastatic sarcoma. One out of 5 patients is free of progression at 2-years.

Radiotherapy in the management of lung oligometastases

In recent years, the development of both medical imaging and new systemic agents (targeted therapy and immunotherapy) have revolutionized the field of oncology, leading to a new entity: oligometastatic disease. Adding local treatment of oligometastases to systemic treatment could lead to prolonged survival with no significant impact on quality of life. Given the high prevalence of lung oligometastases and the new systemic agents coming with increased pulmonary toxicity, this article provides a comprehensive review of the current state-of-art for radiotherapy of lung oligometastases. After reviewing pretreatment workup, the authors define several radiotherapy regimen based on the localization and size of the oligometastases. A comment on the synergistic combination of medical treatment and radiotherapy is also made, projecting on future steps in this specific clinical setting.

Management of oligometastatic/metastatic sarcomas and place of local treatments with focus on modern radiotherapy approaches

Soft tissue sarcomas are a rare and heterogeneous disease. For localized disease, treatment is based on surgery and radiotherapy with or without chemotherapy depending on risk factors. Upfront metastases are present in 7 to 20% of cases, and are localized to the lungs in most of cases. Disseminated disease is generally considered incurable but in selected cases, aggressive local treatment of metastases allowed long survival. Treatment of primary tumour is often debated. Our purpose is to evaluate the literature concerning the role of radiotherapy in the management of primary metastatic soft tissue sarcomas.

Improved local control following dose-escalated stereotactic ablative radiation therapy (SABR) for metastatic sarcomas: An international multi-institutional experience

BACKGROUND

We aimed to characterize local control (LC) and overall survival (OS) following stereotactic ablative radiation therapy (SABR) for extracranial sarcoma metastases.

METHODS

A prospectively-maintained institutional registry was queried for patients with metastases from sarcoma primaries managed with SABR. Kaplan-Meier analysis was utilized for univariate analyses to assess potential prognostic factors regarding LC and OS. A Cox proportional hazards multivariate (MVA) model was employed to further assess initially identified independent variables.

RESULTS

A total of 94 patients with 118 lesions with LC information were identified. Common metastatic sites treated were lung (77), non-spinal bone (15), and spine (10). The median biologically effective dose (BED4) was 175 Gy4 (range56.3 Gy4-360 Gy4) with a median dose/fractionation schedule of 50 Gy/5 fractions. One- and 2-year OS rates were 81.3 % (95 % CI: 71.2-88.1 %6) and 50.5 % (95 % CI: 38.6-61.3 %, respectively. On Cox MVA, advanced age and non-lung metastases were associated with inferior OS (p < 0.03) with patients with 0-2 of these risk factors having estimated 2-year OS of 65.1 %, 38.9 %, and N/A, respectively. One- and 2-year LC rates were 85.3 % (95 % CI: 77.7-90.9 %) and 78.2 % (95 % CI: 67.9-85.6 %), respectively. On MVA, only BED4 < 175 Gy was associated with inferior LC (hazard ratio (HR) = 3.33; p = 0.01). Ten of 118 treated lesions had treatment-related toxicities (all Grade 1-2).

CONCLUSION

Age and lung vs. non-lung metastases were prognostic of OS and should be considered in patient selection for SABR. Dose escalation when feasible with BED4 ≥ 175 Gy is recommended given durable LC achieved without a subsequent increase in toxicity.

Stereotactic body radiotherapy for Ultra-Central lung Tumors: A systematic review and Meta-Analysis and International Stereotactic Radiosurgery Society practice guidelines

BACKGROUND

Stereotactic body radiotherapy (SBRT) is an effective and safe modality for early-stage lung cancer and lung metastases. However, tumors in an ultra-central location pose unique safety considerations. We performed a systematic review and meta-analysis to summarize the current safety and efficacy data and provide practice recommendations on behalf of the International Stereotactic Radiosurgery Society (ISRS).

METHODS

We performed a systematic review using PubMed and EMBASE databases of patients with ultra-central lung tumors treated with SBRT. Studies reporting local control (LC) and/or toxicity were included. Studies with <5 treated lesions, non-English language, re-irradiation, nodal tumors, or mixed outcomes in which ultra-central tumors could not be discerned were excluded. Random-effects meta-analysis was performed for studies reporting relevant endpoints. Meta-regression was conducted to determine the effect of various covariates on the primary outcomes.

RESULTS

602 unique studies were identified of which 27 (one prospective observational, the remainder retrospective) were included, representing 1183 treated targets. All studies defined ultra-central as the planning target volume (PTV) overlapping the proximal bronchial tree (PBT). The most common dose fractionations were 50 Gy/5, 60 Gy/8, and 60 Gy/12 fractions. The pooled 1- and 2-year LC estimates were 92 % and 89 %, respectively. Meta-regression identified biological effective dose (BED10) as a significant predictor of 1-year LC. A total of 109 grade 3-4 toxicity events, with a pooled incidence of 6 %, were reported, most commonly pneumonitis. There were 73 treatment related deaths, with a pooled incidence of 4 %, with the most common being hemoptysis. Anticoagulation, interstitial lung disease, endobronchial tumor, and concomitant targeted therapies were observed risk factors for fatal toxicity events.

CONCLUSION

SBRT for ultra-central lung tumors results in acceptable rates of local control, albeit with risks of severe toxicity. Caution should be taken for appropriate patient selection, consideration of concomitant therapies, and radiotherapy plan design.

Stereotactic Body Radiation Therapy for Sarcoma Pulmonary Metastases

BACKGROUND

Lung metastases are the most common form of distant failure for patients diagnosed with sarcoma with metastasectomy considered for some patients with limited metastatic disease and good performance status. Alternatives to surgery such as stereotactic body radiation therapy (SBRT) can be considered, though data are limited. We present outcomes after SBRT for sarcoma lung metastases.

METHODS

Fifty sarcoma patients with 109 lung metastases were treated with SBRT between 2005 and 2021. Outcomes evaluated included local control (LC), overall survival (OS), and toxicity including lung pneumonitis/fibrosis, chest wall toxicity, dermatitis, brachial plexus, and esophageal toxicity. Systemic therapy receipt before and after SBRT was recorded.

RESULTS

SBRT schedules were divided into 3 cohorts: 30 to 34 Gy/1fx (n=10 [20%]), 48 to 50 Gy/4 to 5fx (n=24[48%]), and 60 Gy/5fx (n=16[32%]). With a median follow-up of 19.5 months, 1/3-year LC rates were 96%/88% and 1/3-year OS 77%/50%, respectively. There was no differences between the 3 regimens in terms of LC, OS, or toxicity. Size >4 cm was a predictor of worse LC ( P =0.031) and worse OS ( P = 0.039) on univariate analysis. The primary pattern of failure was new metastases (64%) of which the majority were in the contralateral lung (52%). One-year chemotherapy-free survival was 85%. Overall, 76% of patients did not require chemotherapy initiation or change of chemotherapy regimen after lung SBRT. Toxicity was reported in 16% of patients overall, including 25%, 20%, and 14% in the 30 to 34 Gy/1fx, 48 to 50 Gy/4 to 5fx, and 60 Gy/5fx cohorts, respectively.

CONCLUSIONS

SBRT outcomes for lung metastases from sarcoma demonstrate high rates of LC and are similar with different dose/fractionation regimens. Lung SBRT is associated with prolonged chemotherapy-free survival. Prospective validation of these results is warranted.

Metastatic adult-type non-rhabdomyosarcoma soft tissue sarcomas in children and adolescents: A cohort study from the European paediatric Soft tissue sarcoma Study Group

BACKGROUND

Limited data exist on the clinical behavior of pediatric non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) with distant metastases at onset, and a clear standard of care has not yet been defined.

METHODS

This cohort study reports on pediatric adult-type metastatic NRSTS enrolled in two concurrent prospective European studies, i.e., the randomized BERNIE study and the single-arm MTS 2008 study developed by the European paediatric Soft tissue sarcoma Study Group. Treatment programs were originally designed for patients with metastatic rhabdomyosarcoma, i.e., nine courses of multidrug chemotherapy (with or without bevacizumab in the BERNIE study), followed by 12 cycles of maintenance therapy, whereas radiotherapy and/or surgery (on primary tumor and/or metastases) were delayed until after seven courses of chemotherapy had been administered.

RESULTS

The study included 61 patients <21 years old treated from July 2008 to December 2016. The lung was the site of metastases in 75% of the cases. All patients received multi-agent chemotherapy, 44% had local therapy to primary tumor, and 18% had treatment of metastases. Median time to progression/relapse was 6 months. A high rate of tumor progression was observed during the initial part of the chemotherapy program. With a median follow-up of 41.5 months (range, 2-111 months), 3-year event-free survival and overall survival were 15.4% (95% confidence interval [CI], 7.6-25.7) and 34.9% (95% CI, 22.7-47.5), respectively. There were no statistically significant differences in outcome depending on the type of treatment administered.

CONCLUSIONS

The study confirmed the overall poor outcome for patients with metastatic NRSTS, whose treatment remains a challenge.

PLAIN LANGUAGE SUMMARY

Pediatric non-rhabdomyosarcoma soft tissue sarcomas form a heterogeneous group of rare tumors. Although recent international studies have defined the standard of care for patients with localized disease, limited data are available on the clinical behavior of patients with distant metastases. This study on 61 metastatic cases treated on two prospective European protocols confirms that the chances of survival of such patients are often dismal and a standard treatment is still lacking.

Treatment outcomes of stereotactic body radiation therapy for pulmonary metastasis from sarcoma: a multicenter, retrospective study

PURPOSE

The aim of this study was to evaluate the treatment outcomes and potential dose-response relationship of stereotactic body radiation therapy (SBRT) for pulmonary metastasis of sarcoma.

MATERIALS AND METHODS

A retrospective review of 39 patients and 71 lesions treated with SBRT from two institutions was performed. The patients had oligometastatic or oligoprogressive disease, or were receiving palliation. Doses of 20-60 Gy were delivered in 1-5 fractions. The local control per tumor (LCpT) was evaluated according to the biologically effective dose with an α/β ratio of 10 (BED₁₀) of the prescribed dose (BED₁₀ ≥ 100 Gy vs. BED₁₀ < 100 Gy). Clinical outcomes per patient, including local control per patient (LCpP), pulmonary progression-free rate (PPFR), any progression-free rate (APFR), and overall survival (OS) were investigated.

RESULTS

The median follow-up period was 27.2 months. The 1-, 2-, and 3-year LCpT rates for the entire cohort were 100.0%, 88.3%, and 73.6%, respectively. There was no observed difference in LCpT between the two BED₁₀ groups (p = 0.180). The 3-year LCpP, PPFR, APFR, and OS rates were 78.1%, 22.7%, 12.9%, and 83.7%, respectively. Five (12.8%) patients with oligometastasis had long-term disease-free intervals, with a median survival period of 40.7 months. Factors that were associated with a worse prognosis were oligoprogression (vs. oligometastasis), multiple pulmonary metastases, and simultaneous extrathoracic metastasis.

CONCLUSION

SBRT for pulmonary metastasis of sarcoma is effective. Some selected patients may achieve durable response. Considerations of SBRT indication and disease extent may be needed as they may influence the prognosis.

Stereotactic body radiotherapy for metastatic sarcoma to the lung: adding to the arsenal of local therapy

INTRODUCTION

Conventional treatment of pulmonary metastatic sarcoma primarily involves surgery, with systemic therapy added in select patients. However, broader applications of radiation therapy techniques have prompted investigation into the use of stereotactic body radiotherapy (SBRT) for treatment of metastatic sarcoma, an attractive non-invasive intervention with potential for lower rates of adverse events than surgery. Current data are limited to retrospective analyses. This study analyzed 2-year local control and overall survival and adverse events in patients prospectively treated with SBRT to pulmonary sarcoma metastases.

METHODS

Patients prospectively treated with SBRT to the lung for biopsy-proven metastatic sarcoma at a single institution from 2010 to 2022 were included. SBRT dose/fractionation treatment regimens ranged from 34 to 54 Gy in 1-10 fractions using photons. Local recurrence, local progression-free survival (LPFS) and overall survival (OS) were calculated from the end of SBRT. Univariable analysis (UVA) was performed using the log-rank test. Multivariable analysis (MVA) was performed using the Cox proportional hazards model. Adverse events due to SBRT were graded based on the Common Terminology Criteria for Adverse Events, version 4.0.

RESULTS

Eighteen patients with metastatic sarcoma were treated to 26 pulmonary metastases. The median local progression-free survival was not met. The median overall survival was not met. The local control rate at 2 years was 96%. 2-year LPFS was 95.5% and OS was 74%. Three patients (16.7%) developed grade 1 adverse events from SBRT. There were no adverse events attributed to radiation that were grade 2 or higher.

CONCLUSION

We report prospective data demonstrating that SBRT for sarcoma pulmonary metastases affords a high rate of local control and low toxicity, consistent with prior sarcoma SBRT retrospective data. This study adds to the wealth of information on SBRT in a radioresistant tumor. Though largely limited to retrospective reviews, current data indicate high rates of local control with favorable toxicity profiles. Therefore, SBRT for pulmonary sarcoma metastases may be considered for properly selected patients.

A prognostic score from a multicentric retrospective analysis of patients affected by sarcoma with metachronous lung metastases undergoing metastasectomy

BACKGROUND

Despite the lack of evidence-based on prospective randomized studies, surgery has become the cornerstone of the treatment in patients with pulmonary oligometastatic sarcomas. Our study aimed to construct a composite prognostic score for metachronous oligometastatic sarcoma patients.

METHODS

A retrospective analysis was performed on data patients who underwent radical surgery for metachronous metastases in six research institutes from January 2010 to December 2018. The log-hazard ratio (HR) obtained from the Cox model was used to derive weighting factors for a continuous prognostic index designed to identify differential outcome risks.

RESULTS

A total of 251 patients were enrolled in the study. In the multivariate analysis, a longer disease-free interval (DFI) and a lower neutrophil-to-lymphocytes ratio (NLR) were predictive of a better overall survival (OS) and disease-free survival (DFS). A prognostic score was developed based on DFI and NLR data, identifying 2 risk class groups for DFS (3-years DFS 20.2% for the high-risk group [HRG]and 46.4% for the low-risk group [LRG] [<0.0001]) and 3 risk groups for OS (3 years OS 53.9% for the HRG vs. 76.9% for the intermediate-risk group and 100% of the LRG (p < 0.0001)).

CONCLUSION

The proposed prognostic score effectively predicts outcomes for patients with lung metachronous oligo-metastases from the surgically treated sarcoma.