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 Radiation Therapy (SBRT) for Spinal Metastases: Real-world Outcomes From an International Multi-institutional SBRT Registry.

OBJECTIVE: The objective of this study was to compare clinical outcomes following single fraction versus fractionated stereotactic body radiotherapy (SBRT) for spinal metastases. MATERIALS AND METHODS: A multi-institutional registry was queried for patients with spinal metastases treated with single-fraction or fractionated SBRT. Potential predictive factors of local control (LC) and overall survival were evaluated. Pretreatment and posttreatment Visual Analog Scale scores were analyzed to examine initial and durable pain responses and complete response (CR) rates. Logistic regression was utilized to assess potential correlations between pain response, biologically effective dose (BED), and fractionation. RESULTS: Four hundred sixty-six patients with 514 lesions treated with SBRT were identified; 209 and 104 lesions had information on LC and pain, respectively. The median pain score of patients with symptoms was 6 (range: 3 to 10). The median follow-up was 8.9 months (range: 0.4 to 125.5 mo). Utilizing Karnofsky Performance Score, age, and primary site (lung and/or nonbreast), 1-year overall survival rates were 76.1%, 59.1%, 54.9%, 37.2%, and 23.5% for patients with 0 to 4 of these factors, respectively (P<0.0001). One- and 2-year LC rates were 79.9% and 73.6%, respectively. Eighty-six patients (82.7%) had an initial pain response with a median decline of 3.5 and a CR rate of 47.1%. Sixty-five patients (62.5%) had a durable pain response with a median decline of 2 and a CR rate of 20.2%. Higher initial CR rates were observed with BED10 ≥51 Gy10 (58.7% vs. 37.9%; P=0.04). CONCLUSIONS: Following SBRT, encouraging palliative responses with >80% and 60% of patients having initial and durable pain responses, respectively. Dose escalation may result in improved initial CR rates. Performance status, age, and primary histology are factors to consider in the absence of pain.

A multi-institutional analysis of outcomes following stereotactic body radiation therapy for management of metastases from squamous cell carcinomas of the head and neck.

Background: There is limited data on clinical outcomes following SBRT for patients with metastatic head and neck squamous cell carcinoma (mHNC). Method: An international SBRT registry was utilized to identify patients. LC and OS were evaluated with the Kaplan-Meier method and a Cox-proportional hazards model for multivariate analysis (MVA) to assess potential prognostic factors. Results: We identified 81 patients with 98 lesions treated with SBRT. Areas treated included the lung (53.0%), non-regional lymph nodes (16.0%), and spine (12.3%). OS rates at 1 year and 2 years were 66.4% and 43.1%, respectively. Utilizing KPS, spinal disease, and GTV, 1-year OS estimates were 90.9%, 70.4%, 54.5%, and 25% for patients with 0-3 of these factors, respectively (p = 0.002). One-year and 2-year LC rates were both 93.3%. Roughly 17% of patients reported toxicities (none Grade 3+). Conclusions: SBRT resulted in promising LC for mHNC patients. Spinal disease, GTV, and KPS should be considered in selecting patients with mHNC that may benefit from SBRT.

Stereotactic body radiation therapy (SBRT) for metastatic renal cell carcinoma: A multi-institutional experience.

Objectives: Examine local control(LC), overall survival(OS), and toxicity following stereotactic body radiation therapy(SBRT) for patients with metastatic renal cell carcinoma(mRCC). Methods: A multi-institutional registry was queried. Potential predictive factors of LC and OS were evaluated with a Cox-proportional hazards model for multivariate analysis(MVA). Results: We identified 115 mRCC patients with 181 lesions. Median biologically effective dose (BED7) was 72.9 Gy7 (range: 42.9-231.4 Gy7) with a median dose/fraction of 10 Gy (range: 5-24 Gy). Utilizing both Karnofsky Performance Score (KPS) and presence of osseous metastatic disease as prognostic indicators, estimated 2-year OS rates were 67.7% (95% CI: 49.9-89.5%), 31.8% (95% CI: 19.0-45.3%), and 20% (95% CI: 1.4-54.7%; p=0.0012). One- and 2-year LC rates were 88.2% and 82.7%, respectively, with no prognostic factors identified. Roughly 13% of patients reported toxicities with one Grade 3-5 toxicity. Conclusion: SBRT was well-tolerated with promising LC. Both KPS and osseous metastatic disease should be considered in determining which patients with mRCC may preferentially benefit from SBRT.

Stereotactic radiosurgery and fractionated stereotactic radiosurgery for vestibular schwannomas: A comparison of clinical outcomes from the RSSearch patient registry.

PURPOSE: To compare clinical outcomes following stereotactic radiosurgery (SRS) and fractionated stereotactic radiosurgery (fSRS) for vestibular schwannomas (VS). MATERIALS/METHODS: We identified 64 VS patients from the RSSearch Patient Registry (12 treated with SRS and 52 patients treated with fSRS). Potential factors predictive of local control (LC) and toxicity were estimated using the Kaplan-Meier method, Cox proportional hazards model, and binary logistic regressions with propensity score weighting. RESULTS: SRS (100%) and fSRS (94.2%) resulted in similar LC (p = 0.33). fSRS was associated with a higher likelihood of experiencing toxicities (42.3% vs. 8.3%; p = 0.054 on time-to-event analysis) that was maintained following a propensity-score weighted binary logistic regression (p = 0.037) and propensity-score weighted Cox regression (p = 0.039; hazard ratio (HR) = 8.85 (95% CI: 1.1 - 70.1)). CONCLUSION: In a multi-institutional analysis, we note equivalent LC but higher toxicity with fSRS compared to SRS for VS.

Clinical Outcomes Following Stereotactic Body Radiation Therapy (SBRT) for Stage I Medically Inoperable Small Cell Lung Carcinoma: A Multi-Institutional Analysis From the RSSearch Patient Registry.

OBJECTIVES: To utilize the RSSearch Patient Registry (RSSPR) to examine local control (LC), overall survival (OS), and toxicities following stereotactic body radiation therapy (SBRT) for stage I (T1-T2/N0) medically inoperable small cell lung carcinoma (SCLC). MATERIALS AND METHODS: We searched the RSSPR for medically inoperable stage I SCLC patients treated with definitive SBRT. Potential predictive factors of OS were estimated using the Kaplan-Meier method as well as a Cox proportional hazards model. RESULTS: Twenty-one patients were identified with medically inoperable stage I SCLC that met inclusion criteria. Fourteen patients had stage IA SCLC (T1N0) and 7 patients had stage IB SCLC (T2N0) with a median gross tumor volume of 10.1 cm (range: 0.72 to 41.4 cm). The median number of fractions was 4 (range: 3 to 5), and the median BED10 was 105.6 Gy10 (range: 72 to 239.7 Gy10). Four patients received adjuvant chemotherapy. One- and 2-year actuarial OS rates were 73.1% (95% confidence interval [CI]: 36.8%-90.1%) and 36.6% (95% CI: 9.0%-65.7%), respectively. Factors found to be associated with 1-year OS on univariate analysis included T2 disease (85.5% vs. 33.3%; P=0.03), adjuvant chemotherapy (100% vs. 66.3%; P=0.11), and gross tumor volume ≥10 cm (100% vs. 52.5%; P=0.10). On multivariate analysis, adjuvant chemotherapy was associated with improved OS (hazard ratio=0.07 [95% CI: 0.13-0.37; P=0.002]). The 1-, 2-, and 3-year LC rates were 100%, and 1- and 2-year progression-free survival (PFS) rates were 85.7% (95% CI: 33.4-97.9%) and 42.9% (95% CI: 1.1-85.3%), respectively. Similar to OS, patients with T1N0 disease had superior PFS as compared to T2N0 disease (P=0.01). Toxicities were reported by 3/21 (14.3%) of patients with none ≥ grade 3 and no esophageal toxicities. CONCLUSIONS: SBRT was well-tolerated in the treatment of stage I SCLC with excellent LC achieved. Patients with T1N0 stage IA SCLC were noted to have improved PFS and OS following SBRT as compared with T2N0 Stage IB SCLC. Adjuvant chemotherapy was found to result in improved OS for stage I SCLC patients over SBRT alone.

Salvage Stereotactic Body Radiation Therapy for Locally Recurrent Previously Irradiated Head and Neck Squamous Cell Carcinoma: An Analysis from the RSSearch® Registry.

Objectives To report on overall survival (OS), local control (LC), dose-outcome relationships, and related toxicities following stereotactic body radiation therapy (SBRT) for locally recurrent, previously irradiated squamous cell carcinoma of the head and neck (rSCCHN). Methods We queried the prospectively-maintained RSSearch® Registry for patients with rSCCHN treated with five-fraction SBRT from January 2008 to November 2016. Patients with non-squamous cell histology, missing registry data regarding prior irradiation, those treated with less than five fractions of SBRT, and those treated with SBRT in primary or boost settings were excluded. LC and OS were estimated using the Kaplan-Meier method with comparisons between groups completed using log-rank t-tests and multivariable Cox regression. Logistic regression analyses were used to examine factors predictive of toxicity. Results Forty-five rSCCHN patients treated with SBRT delivered in five fractions at 12 radiotherapy centers were identified. Prescription doses ≥ 40 Gy were associated with higher one-year rates of OS, LC, and a higher likelihood of experiencing toxicities. Acute and late toxicity rates were low (22.2% and 15.6%, respectively) and were all Grade 1-2 with only one late Grade 3 esophagitis. Conclusion Salvage SBRT for rSCCHN resulted in outcomes comparable to prior single-institutional reports in a multi-institutional cohort across clinical settings with low toxicity, thus supporting more widespread adoption of SBRT with recommended doses ≥ 40 Gy.

Results of a 2-arm Phase II study of 9-nitrocamptothecin in patients with advanced soft-tissue sarcomas.

BACKGROUND: The authors conducted a 2-arm Phase II trial of 9-nitrocamptothecin (9-NC), an oral topoisomerase I inhibitor, to define response rates in patients with gastrointestinal (GI) leiomyosarcomas and other soft-tissue sarcomas (STS). METHODS: Patients were required to provide informed consent and have measurable disease, Zubrod performance status < or = 2, and adequate organ function. 9-NC was administered orally at 1.5 mg/m(2) per day x 5 days every week. Response evaluation was performed at 8 weeks, and those with stable or responding disease continued treatment until maximal response was achieved. A total of 56 patients (30 females and 26 males) with a median age of 55 years (range, 19-79 years) were enrolled on the study. Seventeen patients were enrolled on the GI leiomyosarcoma arm; only 1 minor response, lasting < 8 weeks in a patient with liver metastases, was noted, and so this arm was terminated. Thirty-nine patients were entered on the other STS arm. RESULTS: Three patients achieved a partial response (response rate, 8%) for durations of 4, 6, and 13 months, respectively. Fourteen patients had stable disease for a median of 4 months (range, 2-8 months). Two patients died of disease during the first 2 months. Four other patients required hospitalization for nausea, vomiting, and dehydration. Other toxicities included diarrhea (36 patients, 5 with Grade 3 toxicity); fatigue (42 patients, 11 with Grade 3 toxicity); anorexia (32 patients, 1 with Grade 3 toxicity); nausea (37 patients, 2 with Grade 3 toxicity); vomiting (24 patients, 3 with Grade 3 toxicity); neutropenia (14 patients, 5 with Grade 3 toxicity); and thrombocytopenia (16 patients, 5 with Grade 3 or 4 toxicity). CONCLUSIONS: 9-NC is well tolerated but inactive in GI leiomyosarcomas and has minimal activity in previously treated patients with STS.