The role of spine stereotactic radiosurgery for patients with breast cancer metastases.

PURPOSE: Breast cancer that metastasizes to the spine is associated with low quality of life and poor survival. Radiosurgery has an increasing role in this patient population. This single-institution (2003-2023) study analyzes clinical outcomes and prognostic factors for patients who underwent spinal stereotactic radiosurgery (SSRS) for metastatic breast cancer. METHODS: Ninety patients (155 unique breast cancer spinal metastases) were treated with SSRS. The median age was 57 years (range: 35-88), and the median KPS was 80 (range: 40-100). Forty-two (27%) lesions were managed surgically prior to radiosurgery. At SSRS, 75 (48%) lesions impinged or compressed the spinal cord per the epidural spinal cord scale (ESCC). Seventy-nine (51%) lesions were categorized as potentially unstable or unstable by the Spinal Instability Neoplastic Score (SINS). RESULTS: The median follow-up was 15 months (range: 1-183). The median single-session tumor volume was 25.4 cc (range: 2-197), and the median single-fraction prescription dose was 17 Gy (range: 12-25). Seven (5%) lesions locally progressed. The 1-, 2-, and 5-year local control rates were 98%, 97%, and 92%, respectively. The median overall survival (OS) for the cohort was 32 months (range: 2-183). The 1-, 2-, and 5-year OS rates were 72%, 53%, and 30%, respectively. On univariate analysis, KPS ≥ 80 (p = 0.009, HR: 0.51, 95% CI: 0.31-0.84) was associated with improved OS. Patient-reported pain improved (68%), remained stable (29%), or worsened (3%) following radiosurgery. Fifteen (10%) radiation-induced toxicities were reported. CONCLUSIONS: Spinal radiosurgery is a safe and highly effective long-term treatment modality for metastases to the spine that originate from breast cancer.

Salvage stereotactic radiosurgery for recurrent gliomas with prior radiation therapy.

This study aims to assess the viability of salvage stereotactic radiosurgery (SRS) for recurrent malignant gliomas through assessing overall survival, local control and toxicity. We performed a retrospective review of 65 patients with 76 lesions (55 high-grade, 21 low-grade) treated with salvage SRS between 2002 and   2012. Median follow-up from salvage SRS was 14.9 months (IQR: 0.9-28.1), 8.3 months (IQR: 4.0-13.3) and 8.5 months (IQR: 3.9-15.8) for low-grade, high-grade, and combined, respectively. A 12-month overall survival from salvage SRS was 68.4, 38.7 and 47.3% for low-grade, high-grade and combined respectively. A total of 6-month local control was 86.2, 53.8 and 65.3% for low-grade, high-grade and combined, respectively. Our results indicate salvage SRS can provide acceptable survival and local control with minimal toxicity.

Dosimetric comparison between cone/Iris-based and InCise MLC-based CyberKnife plans for single and multiple brain metastases.

We performed an evaluation of the CyberKnife InCise MLC by comparing plan qualities for single and multiple brain lesions generated using the first version of InCise MLC, fixed cone, and Iris collimators. We also investigated differences in delivery efficiency among the three collimators. Twenty-four patients with single or multiple brain mets treated previously in our clinic on a CyberKnife M6 using cone/Iris collimators were selected for this study. Treatment plans were generated for all lesions using the InCise MLC. Number of monitor units, delivery time, target coverage, conformity index, and dose falloff were compared between MLC- and clinical cone/Iris-based plans. Statistical analysis was performed using the non-parametric Wilcoxon-Mann-Whitney signed-rank test. The planning accuracy of the MLC-based plans was validated using chamber and film measurements. The InCise MLC-based plans achieved mean dose and target coverage comparable to the cone/Iris-based plans. Although the conformity indices of the MLC-based plans were slightly higher than those of the cone/Iris-based plans, beam delivery time for the MLC-based plans was shorter by 30% ~ 40%. For smaller targets or cases with OARs located close to or abutting target volumes, MLC-based plans provided inferior dose conformity compared to cone/Iris-based plans. The QA results of MLC-based plans were within 5% absolute dose difference with over 90% gamma passing rate using 2%/2 mm gamma criteria. The first version of InCise MLC could be a useful delivery modality, especially for clinical situations for which delivery time is a limiting factor or for multitarget cases.

A method to improve dose gradient for robotic radiosurgery.

For targets with substantial volume, collimators of relatively large size are usually selected to minimize the treatment time in robotic radiosurgery. Their large penumbrae may adversely affect the dose gradient around the target. In this study, we implement and evaluate an inner-shell planning method to increase the dose gradient and reduce dose to normal tissues. Ten patients previously treated with CyberKnife M6 system were randomly selected with the only criterion being that PTV be larger than 2 cm(3). A new plan was generated for each patient in which the PTV was split into two regions: a 5 mm inner shell and a core, and a 7.5 mm Iris collimator was exclusively applied to the shell, with other appropriate collimators applied to the core depending on its size. The optimization objective, functions, and constraints were the same as in the corresponding clinical plan. The results were analyzed for V12 Gy, V9 Gy, V5 Gy, and gradient index (GI). Volume reduction was found for the inner-shell method at all studied dose levels as compared to the clinical plans. The absolute dose-volume reduction ranged from 0.05 cm(3) to 18.5 cm(3) with a mean of 5.6 cm(3) for 12 Gy, from 0.2 cm(3) to 38.1 cm(3) with a mean of 9.8 cm(3) for 9 Gy, and from 1.5 cm(3) to 115.7 cm(3) with a mean of 24.8 cm(3) for 5 Gy, respectively. The GI reduction ranged from 3.2% to 23.6%, with a mean of 12.6%. Paired t-test for GI has a p-value of 0.0014. The range for treatment time increase is from -3 min to 20 min, with a mean of 7.0 min. We conclude that irradiating the PTV periphery exclusively with the 7.5 mm Iris collimator, rather than applying mixed collimators to the whole PTV, can substantially improve the dose gradient, while maintaining good coverage, conformity, and reasonable treatment time.

Stereotactic Radiosurgery for Patients with Spinal Metastases from Thyroid Cancer: A 20-Year Experience.

OBJECTIVE: Primary thyroid cancer metastasizing to the spine portends poor survival and low quality of life. Current management strategies continue to evolve. This single-institution retrospective study analyzes outcomes after spinal stereotactic radiosurgery for patients with spinal metastases from thyroid cancer. METHODS: Nineteen patients (median age: 64.5 years) were treated with stereotactic radiosurgery (SRS) for spinal primary thyroid metastases (40 metastases, 47 vertebral levels) between 2003 and 2023. Nineteen (47.5%) lesions had epidural involvement and 20 (50%) lesions were classified as potentially unstable or unstable via the Spinal Instability Neoplastic Score. The median tumor volume per lesion was 33 cc (range: 1.5-153). The median single fraction prescription dose was 20 Gy (range: 12-23.5). RESULTS: The median follow-up period was 15 months (range: 2-40). Five (12.8%) lesions locally progressed at a median of 9 months (range: 4-26) after SRS. The 1-, 2-, and 3-year local tumor control rates per lesion were 90.4%, 83.5%, and 75.9%, respectively. On univariate analysis, age at SRS >70 years (P = 0.05, hazard ratio: 6.86, 95% confidence interval: 1.01-46.7) was significantly correlated with lower rates of local tumor control. The median overall survival was 35 months (range: 2-141). The 1-, 2-, and 3-year overall survival rates were 73.7%, 50.4%, and 43.2%, respectively. For 33 lesions initially associated with pain, patients reported pain improvement (22 lesions, 66.7%), stability (10 lesions, 30.3%), and worsening (1 lesion, 3.0%) after SRS. One patient developed dysphagia 4 months after SRS treatment. CONCLUSIONS: SRS can be utilized as an effective and safe primary and adjuvant treatment option for primary thyroid metastases to the spine.

Preoperative stereotactic radiosurgery for cerebral metastases: safe, effective, and decreases steroid dependency.

OBJECTIVE: Preoperative stereotactic radiosurgery (SRS) is emerging as a viable alternative to standard postoperative SRS. Studies have suggested that preoperative SRS provides comparable tumor control and overall survival (OS) and may reduce the incidence of leptomeningeal disease (LMD) and adverse radiation effects (AREs). It is unknown, however, if preoperative SRS remains effective in cohorts including large brain metastases (> 14 cm3) or if preoperative SRS affects steroid taper/immunotherapy. Here, the authors report the results of a phase 2 single-arm trial assessing a prospectively acquired series of 26 patients who underwent preoperative SRS, without a volumetric cutoff, compared with a propensity score-matched concurrent cohort of 30 patients who underwent postoperative SRS to address these salient questions. METHODS: Demographics, oncological history, surgical details, and outcomes were collected from the medical records. Coprimary endpoints were local tumor control (LTC) and a composite outcome of LTC, ARE, and LMD. Additional outcomes were OS, steroid taper details, and immunotherapy resumption. For survival analyses, cohorts were propensity score matched. RESULTS: Preoperative and postoperative SRS patients were comparable in terms of age, sex, Karnofsky Performance Status score, oncological history, and operative details. Gross tumor volume (GTV) was significantly higher in the preoperative group (median 12.2 vs 5.3 cm3, p < 0.001). One-year LTC (preoperative SRS: 77.2% vs postoperative SRS: 82.5%, p = 0.61) and composite outcome (68.3% vs 72.7%, p = 0.38) were not significantly different between the groups. In multivariable analysis, preoperative SRS did not have a significant effect on LTC (HR 1.57 [95% CI 0.38-6.49], p = 0.536) or the composite outcome (HR 1.18 [95% CI 0.38-3.72], p = 0.771), although the confidence intervals were large. The median OS (preoperative SRS: 17.0 vs postoperative SRS: 14.0 months, p = 0.61) was not significantly different. Rates of LMD were nonsignificantly lower in the preoperative SRS group (3.8% vs 16.7%, p = 0.200). Greater GTV volume was associated with prolonged (> 10 days) steroid taper (OR 1.24 [95% CI 1.04-1.55], p = 0.032). However, in multivariable analysis, preoperative SRS markedly reduced the steroid taper length (OR 0.13 [95% CI 0.02-0.61], p = 0.016). Time to immunotherapy was shorter in the preoperative SRS group (36 [IQR 26, 76] vs OR 228 [IQR 129, 436] days, p = 0.02). CONCLUSIONS: Compared with postoperative SRS, preoperative SRS is a safe and effective strategy in the management of cerebral metastases of all sizes and provides comparable tumor control without increased adverse effects. Notably, preoperative SRS enabled rapid steroid taper, even in larger tumors. Future studies should specifically examine the interaction of preoperative SRS with steroid usage and resumption of systemic therapies and the subsequent effects on systemic progression and OS.

Stereotactic Radiosurgery vs Conventional Radiotherapy for Localized Vertebral Metastases of the Spine: Phase 3 Results of NRG Oncology/RTOG 0631 Randomized Clinical Trial.

Importance: Spine metastasis can be treated with high-dose radiation therapy with advanced delivery technology for long-term tumor and pain control. Objective: To assess whether patient-reported pain relief was improved with stereotactic radiosurgery (SRS) as compared with conventional external beam radiotherapy (cEBRT) for patients with 1 to 3 sites of vertebral metastases. Design, Setting, and Participants: In this randomized clinical trial, patients with 1 to 3 vertebral metastases were randomized 2:1 to the SRS or cEBRT groups. This NRG 0631 phase 3 study was performed as multi-institutional enrollment within NRG Oncology. Eligibility criteria included the following: (1) solitary vertebral metastasis, (2) 2 contiguous vertebral levels involved, or (3) maximum of 3 separate sites. Each site may involve up to 2 contiguous vertebral bodies. A total of 353 patients enrolled in the trial, and 339 patients were analyzed. This analysis includes data extracted on March 9, 2020. Interventions: Patients randomized to the SRS group were treated with a single dose of 16 or 18 Gy (to convert to rad, multiply by 100) given to the involved vertebral level(s) only, not including any additional spine levels. Patients assigned to cEBRT were treated with 8 Gy given to the involved vertebra plus 1 additional vertebra above and below. Main Outcomes and Measures: The primary end point was patient-reported pain response defined as at least a 3-point improvement on the Numerical Rating Pain Scale (NRPS) without worsening in pain at the secondary site(s) or the use of pain medication. Secondary end points included treatment-related toxic effects, quality of life, and long-term effects on vertebral bone and spinal cord. Results: A total of 339 patients (mean [SD] age of SRS group vs cEBRT group, respectively, 61.9 [13.1] years vs 63.7 [11.9] years; 114 [54.5%] male in SRS group vs 70 [53.8%] male in cEBRT group) were analyzed. The baseline mean (SD) pain score at the index vertebra was 6.06 (2.61) in the SRS group and 5.88 (2.41) in the cEBRT group. The primary end point of pain response at 3 months favored cEBRT (41.3% for SRS vs 60.5% for cEBRT; difference, -19 percentage points; 95% CI, -32.9 to -5.5; 1-sided P = .99; 2-sided P = .01). Zubrod score (a measure of performance status ranging from 0 to 4, with 0 being fully functional and asymptomatic, and 4 being bedridden) was the significant factor influencing pain response. There were no differences in the proportion of acute or late adverse effects. Vertebral compression fracture at 24 months was 19.5% with SRS and 21.6% with cEBRT (P = .59). There were no spinal cord complications reported at 24 months. Conclusions and Relevance: In this randomized clinical trial, superiority of SRS for the primary end point of patient-reported pain response at 3 months was not found, and there were no spinal cord complications at 2 years after SRS. This finding may inform further investigation of using spine radiosurgery in the setting of oligometastases, where durability of cancer control is essential. Trial Registration: ClinicalTrials.gov Identifier: NCT00922974.

Stereotactic body radiation therapy for adrenal metastases: a retrospective review of a noninvasive therapeutic strategy.

AIMS: The role of radiation therapy in the treatment of adrenal metastases has traditionally been a palliative one, achieving excellent pain control with very limited toxicity. Recent studies have focused on the potential role of stereotactic body radiation therapy (SBRT) with curative intent in limited metastatic disease, its potential to reduce tumor burden and to prevent symptomatic progression. This study reports the single-institution outcomes of SBRT utilizing both single fraction and hypofractionated regimens in the treatment of adrenal metastases. METHODS: A total of seven patients with nine adrenal metastases treated with SBRT at the University of Pittsburgh Cancer Institute were retrospectively studied. The primary malignancies consisted of non-small-cell lung cancer (n = 4), small-cell lung cancer (n = 1) and hepatocellular carcinoma (n = 2). RESULTS: Five lesions were treated in a single fraction to a median prescription dose of 16 Gy (range: 10-22 Gy) to the 80% isodose line. The remaining four lesions were treated over three fractions to a median prescription dose of 27 Gy (range: 24-36 Gy), with a median prescription isodose line of 94% (range: 80-94%). Median follow-up from the primary diagnosis was 38 months (range: 7-88 months) and from SBRT was 14 months (range: 1-60 months). Follow-up imaging for six patients, and eight metastatic lesions, revealed one complete response, two partial responses and five stable lesions. Five of the lesions eventually failed locally, with a median time to failure of 12 months and actuarial local control of 63% at 1 year. The median overall survival was 8 months from SBRT. CONCLUSION: SBRT can be safely delivered in single fraction, or hypofractionated, regimens for the treatment of adrenal metastases.

Stereotactic radiosurgery to the resection cavity of brain metastases: a retrospective analysis and literature review.

PURPOSE: The aim of this study was to analyze results of stereotactic radiosurgery (SRS) as adjuvant therapy for resected brain metastases. METHODS: Medical records of patients treated at a single institution with SRS to the postoperative cavity of brain metastases were retrospectively reviewed. Patients who completed the prescribed SRS regimen following gross-total resection and had no previous whole brain radiotherapy were included in the study. Kaplan-Meier analyses were used to estimate local (LC) and intracranial control (IC), and overall survival (OS) rates. RESULTS: Between April 2005 and July 2010, 77 patients (median age 63 years) with 89 metastases met the inclusion criteria. The median prescription dose was 18 Gy (12-27 Gy) delivered in 1-3 fractions for a median target volume of 7.6 cm(3) (0.5-59 cm(3)). The 6-month, 1-year, and 2-year LC rates were 76.1, 76.1, and 74.3%, respectively. The 6-month, 1-year, and 2-year IC rates were 75.2, 54, and 43.6%, respectively. With a median follow-up of 13.8 months, the median OS was 14.5 months (1.9-51.4 months) after SRS. The overall 6-month, 1-year, and 2-year OS rates were 91, 62.5, and 43.6%, respectively. Complications included 2 patients with radiation necrosis. CONCLUSION: Adjuvant radiosurgery to the tumor cavity of resected brain metastases is well-tolerated and achieves LC in the majority of patients.

Long term outcomes with linear accelerator stereotactic radiosurgery for treatment of jugulotympanic paragangliomas.

BACKGROUND: Data supporting linear accelerator (linac) stereotactic radiosurgery (SRS) for jugulotympanic paragangliomas (JTPs) come from small series with minimal follow-up. Herein, we report a large series of JTPs with extended follow-up after frameless linac-based SRS. METHODS: JTPs treated with linac-based SRS from 2002 to 2019 with 1+ follow-up image were reviewed for treatment failure (radiographic or clinical progression, or persistent symptoms after SRS requiring intervention) and late toxicities (CTCAE v5.0). RESULTS: Forty JTPs were identified; 30 were treated with a multifraction regimen. Median clinical and radiographic follow-up was 79.7 (interquartile range [IQR] 31.7-156.9) and 54.4 months (IQR 17.9-105.1), respectively, with a median 4.5 follow-up scans (IQR 2-9). Seven-year progression-free survival (PFS) was 97.0% (95% confidence interval 91.1%-100.0%). PFS was similar between single- and multifraction regimens (log rank P = .99). Toxicity was seen in 7.7% (no grade III). CONCLUSIONS: With extended clinical and radiographic follow-up, frameless linac-based SRS provides excellent local control with mild toxicity <8%.

EUS-guided fiducial placement for stereotactic body radiotherapy in locally advanced and recurrent pancreatic cancer.

BACKGROUND: Stereotactic body radiotherapy (SBRT) has been approved for the treatment of locally advanced pancreatic cancer. Placement of gold fiducials is required for real-time tracking and delivery of a high-dose therapeutic beam of radiation to the tumor. Traditionally, fiducials have been placed either intraoperatively or percutaneously. Recently, EUS-guided fiducial placement has been reported, but the safety and feasibility of this approach is not well defined. OBJECTIVE: The aim of this study was to determine the safety, feasibility, and limitations of EUS-guided placement of 0.8 x 5.0 mm fiducials via a 19-gauge needle for locally advanced and recurrent pancreatic cancer. DESIGN: Prospective study of patients with either locally advanced or recurrent pancreatic cancer referred for EUS-guided fiducial placement for SBRT at our institution over a 3-year period. SETTING: Tertiary referral center conducting >1800 EUS procedures annually. MAIN OUTCOME MEASUREMENTS: Primary outcome measurements included success, complications, and technical limitations of EUS-guided fiducial placement in pancreatic cancer. In addition, the percentage of patients successfully completing SBRT after EUS-guided fiducial placement was determined. RESULTS: A total of 51 patients (mean age 73 years; 57% male) with locally advanced (n = 36) and recurrent (n = 15) pancreatic cancer were referred for EUS-guided fiducial placement. Fiducials were successfully placed in 46 patients (90%), with technical failures occurring in 4 patients (8%) with recurrent cancer after pancreaticoduodenectomy. In 3 patients (7%), the fiducials spontaneously migrated from the original site of injection, thereby requiring a second EUS procedure for placement of additional fiducials. Of the 46 patients with fiducials placed under EUS guidance, 42 patients (91%) successfully completed SBRT. Two patients experienced disease progression before SBRT, 1 patient was lost to follow-up, and 1 patient experienced a complication at ERCP that precluded further therapy. Only 1 complication (2%), of mild pancreatitis, occurred in a patient undergoing simultaneous placement of fiducials and celiac plexus neurolysis for intractable abdominal pain. LIMITATIONS: Single-center experience and lack of a formal follow-up protocol to assess for complications. CONCLUSION: EUS-guided fiducial placement for SBRT in locally advanced and recurrent pancreatic cancer is safe and feasible. Successful placement was achieved in 90% of patients, with a low complication rate (2%). Furthermore, 91% of patients successfully completed SBRT after EUS-guided fiducial delivery. Although fiducials can spontaneously migrate from the initial injection site, the rate of migration is relatively low (7%), and no migration-related complications occurred over the course of this study. Limitations to EUS-guided fiducial placement may include surgically altered anatomy (pancreaticoduodenectomy) in patients with recurrent pancreatic cancer.

Self-reported weight loss practices among African American and Hispanic adults in the United States.

OBJECTIVE: To describe weight loss methods used and interactions with health care professionals on the issue of weight among African Americans and Hispanics. METHODS: Five hundred thirty-seven African American and 526 Hispanic adults who self-described as being overweight participated in a telephone interview. RESULTS: Exercise and healthy eating were the 2 most commonly used weight loss methods among both groups; prescription medications were the least-utilized weight loss aid. Forty-one percent of African Americans and 35% of Hispanics reported having been advised to lose weight by a health care professional. CONCLUSIONS: Do-it-yourself approaches to weight loss predominate among African Americans and Hispanics; formal assistance is rarely used. Physician advice on weight loss is suboptimal.

Patterns of Failure After Adjuvant Stereotactic Body Radiation Therapy for Pancreatic Cancer With Close or Positive Margins.

PURPOSE: There is no consensus on treatment volumes for adjuvant stereotactic body radiation therapy (SBRT) for pancreatic cancer. Herein, we report patterns of failure after pancreatic SBRT for close/positive margins, which may inform target volume design. METHODS AND MATERIALS: An institutional review board-approved retrospective review of patients with pancreatic adenocarcinoma treated with adjuvant SBRT for close/positive margins from 2009 to 2018 was conducted. Patterns of failure were defined as local (LF) within the tumor bed, regional (RF) within lymph nodes or anastomoses, or distant (DF). The cumulative incidence of locoregional failure was calculated using the cumulative incidence function accounting for the competing risk of death. LFs were mapped to the planning target volume (PTV) and classified as in-field (completely within the PTV), marginal (partially within the PTV), or out-of-field (completely outside the PTV). The location of LFs was compared with the Radiation Therapy Oncology Group 0848 contouring atlas to determine whether standard postoperative radiation therapy volumes would have included the LF. RESULTS: Seventy-six patients were treated with adjuvant SBRT for close (51.3%) or positive (48.7%) margins. Most (81.6%) received 36 Gy in 3 fractions, with a median PTV volume of 17.8 cc (interquartile range, 12.1-25.6). With a median follow-up of 17.0 months (interquartile range, 7.3-28.4), crude rates of first isolated LF, isolated RF, and DF +/- LF or RF were 9.2%, 6.6%, and 56.6%, respectively. Two-year cumulative incidences of LF, RF, locoregional failure, and DF were 34.9%, 30.8%, 49.2%, and 60.4%, respectively. Of 28 reviewable LFs, 21.4% were in-field while the remainder were completely outside (60.7%) or partially outside (17.9%) the PTV. Most LFs (92.9%) would have been encompassed by the Radiation Therapy Oncology Group consensus target volumes. CONCLUSIONS: After adjuvant pancreatic SBRT for close/positive margins, the majority of LFs were outside the PTV but within contemporary target volumes for conventional radiation therapy.

Salvage Curative-Intent Reirradiation Stereotactic Body Radiation Therapy for Isolated Pelvic and/or Paraortic Recurrences of Gynecologic Malignancies.

PURPOSE: To determine the feasibility of stereotactic body radiation therapy (SBRT) for isolated nodal recurrences of gynecologic malignancies within a previously irradiated area. METHODS AND MATERIALS: A retrospective review was performed on 20 patients who underwent 21 curative-intent reirradiation SBRT treatments for locoregional recurrences of gynecologic malignancies. Disease control and survival outcomes were analyzed with the Kaplan-Meier method and log-rank test. Treatment toxicities were graded according to Common Terminology Criteria for Adverse Events version 4.03. RESULTS: All patients had an isolated pelvic, paraortic, or intra-abdominal nodal recurrence, with the exception of 1 patient who had a concurrent paraortic and right acetabulum metastasis, both of which were irradiated with SBRT. Primary sites included cervix (30.0%), uterus (55.0%), vulva (5.0%), vagina (5.0%), and ovary (5.0%). Median prior external beam radiation therapy dose was 45 Gy. Recurrences were in field in 14 (66.7%) and marginal in 7 (33.3%). SBRT was directed to the pelvis in 13 cases (61.9%) and to paraortic or celiac nodes in 8 (38.1%). The most common SBRT regimen was 40 to 45 Gy in 5 fractions (n = 12). At a median follow-up of 31.2 months, 3-year actuarial in-field local control, distant progression-free survival, and overall survival were 61.4%, 44.0%, and 51.9%, respectively. At the time of last follow-up, 9 (45.0%) patients remained alive without evidence of disease. Actuarial 3-year risk of grade ≥2 and grade ≥3 late toxicities was 38.1% and 14.3%, respectively. CONCLUSIONS: SBRT for isolated pelvic or intra-abdominal recurrences of gynecologic malignancies within a previously irradiated field is feasible with an acceptable toxicity rate. With this approach, about half of patients achieved durable disease-free survival.

Stereotactic Ablative Radiation Therapy for Unresectable Colorectal Oligometastases.

PURPOSE: Patients with oligometastatic colorectal cancer have demonstrated excellent clinical outcomes with surgical resection of hepatic and pulmonary metastases. Stereotactic ablative radiation therapy (SABR) has emerged as an alternative local therapy for nonsurgical candidates. Herein, we report the oncologic and patient-reported quality-of-life (PR-QoL) outcomes for a subset of patients with oligometastatic colorectal cancer who were treated in a prospective phase 2 multicenter clinical trial. METHODS AND MATERIALS: Patients with a pathologically proven diagnosis of oligometastatic colorectal cancer were enrolled as part of a prospective study. SABR dose and fractionation schedules were dependent on the lesion location and size. Patient follow-up occurred 6 weeks after completion of SABR and at 3-month intervals for the following 3 years. Patients received the Functional Assessment of Cancer Therapy-General questionnaire at baseline and at each follow-up visit to assess PR-QoL. The total Functional Assessment of Cancer Therapy-General questionnaire scores were compared with those from baseline using the Wilcoxon signed rank test. Overall survival, local progression-free survival (PFS), and distant PFS were calculated using the Kaplan-Meier estimation to the date of the last follow-up visit/death or local/distant failure. RESULTS: A total of 31 patients with oligometastatic colorectal cancer with 1 (71.0%), 2 (16.1%), 3 (3.2%), 4 (3.2%), or 5 (6.5%) metastatic lesions were identified. After a median follow-up time of 50.1 months, the median OS from the time of completion of the SABR was 53.9 months (95% confidence interval, 23.2-84.6), and the 5-year OS, local PFS, and distant PFS were 45%, 83%, and 27%, respectively. Acute grade 2+ toxicity was 9.7% (pain, nausea, fatigue) and late grade 3+ toxicity (small bowel obstruction) was 3.2% with no significant change in PR-QoL in the year after SABR. CONCLUSIONS: This subset analysis of a prospective phase 2 study demonstrates that SABR is a safe and effective treatment option for patients with unresectable oligometastic colorectal cancer. In addition, SABR of oligometastatic disease preserves PR-QoL.

Initial Results of a Multicenter Phase 2 Trial of Stereotactic Ablative Radiation Therapy for Oligometastatic Cancer.

PURPOSE: Oligometastatic disease has emerged as a potentially curable state in the spectrum of cancer progression. Aggressive local therapy such as stereotactic ablative radiation therapy (SABR) may improve oncologic outcomes. Herein, we report the initial oncologic outcomes and patient-reported quality of life (PR-QoL) from a phase 2 multicenter trial for patients with oliogmetastatic disease. METHODS AND MATERIALS: Patients with oligometastatic disease (1-5 metastases) were prospectively recruited between 2011 and 2017. SABR dose and fractionation was dependent on the lesion size and location. Patient follow-up occurred within 6 weeks of completion of SABR and at 3-month intervals. Patients received a Functional Assessment of Cancer Therapy-General questionnaire at baseline and at each follow-up to assess for PR-QoL. Median follow-up was calculated by reverse Kaplan-Meier method. Overall survival (OS), local progression-free survival, and distant progression-free survival were calculated using the Kaplan-Meier method. RESULTS: We enrolled 147 patients with oligometastatic cancer with a median age of 66.4 years (interquartile range, 59.9-74.6). The most common primary tumors included lung (21.8%, non-small cell: n = 29, small cell: n = 3), colorectal adenocarcinoma (21.1%), and head and neck (10.9%, squamous cell carcinoma: n = 11). In a median follow-up of 41.3 months (interquartile range: 14.6-59.0), the median OS was 42.3 months (95% confidence interval: 27.4-∞) with 5-year OS of 43%. Five-year local progression-free survival and distant progression-free survival were 74% and 17%, respectively. Acute grade 2+ and 3+ toxicity were 7.5% and 2.0%, respectively, and late grade 2+ and 3+ toxicity were both 1.4%. There was no significant change in quality of life at completion and 6 weeks, 3 months, and 9 months after treatment. At 6 and 12 months, patients were found to have statistically significant improvement in PR-QoL. CONCLUSIONS: This multicenter prospective phase 2 study demonstrates that SABR for recurrent oligometastatic cancer is a feasible and tolerable treatment option with minimal acute and late grade 3 toxicity. Additionally, PR-QoL was not adversely affected.

Initial Results of a Prospective Study of Adjuvant Pancreatic Stereotactic Body Radiation Therapy for Close or Positive Margins.

PURPOSE: Patients with close or positive margins after surgery for pancreatic carcinoma are at a high risk for recurrence. Stereotactic body radiation therapy (SBRT) allows for safe dose escalation with great conformity and short duration of treatment. Herein, we report the initial results of a prospective observational study that evaluated the efficacy and safety of this treatment option. METHODS AND MATERIALS: Patients eligible for the study had pathologically proven T1-4N0-1M0 pancreatic adenocarcinoma with a positive margin (≤1 mm) or a close margin defined as <2.5 mm. Patients were treated with either neoadjuvant or adjuvant chemotherapy, if eligible for systemic therapy. All patients received 36 Gy in 3 fractions to the close or positive margin site. RESULTS: From February 2013 to January 2018, 50 patients were enrolled with 49 patients treated on protocol and included in the analysis. The median age was 71 years. The median clinical target volume was 11.3 cc and median planning target volume 22.0 cc. The median overall survival was 23.7 months (95% confidence interval, 13.6-33.8). Local progression-free survival at 1 and 2 years was 85% and 77%, respectively. Regional progression-free survival at 1 and 2 years was 73% and 73%, respectively. Distant metastases-free survival was 57% and 49% at 1 and 2 years, respectively. Grade 3+ radiation toxicity was only 4.1% and occurred in 2 patients. CONCLUSIONS: Adjuvant pancreatic SBRT was shown to be a safe and feasible treatment option for patients with high-risk pancreatic adenocarcinoma and close or positive margins. This is the first prospective study of SBRT in high-risk postoperative pancreatic cancer. Our results yielded significant local and regional control with low rates of acute toxicity. This technique does not interrupt the administration of systemically dosed multiagent chemotherapy and can be safely interdigitated between cycles because SBRT is only 1 week of treatment.

Fractionated stereotactic body radiation therapy in the treatment of primary, recurrent, and metastatic lung tumors: the role of positron emission tomography/computed tomography-based treatment planning.

PURPOSE: The aim of this study was to assess the outcomes of patients treated with stereotactic body radiation therapy (SBRT) in patients with primary, recurrent, or metastatic lung lesions, with a focus on positron emission tomography (PET)/computed tomography (CT)-based management. PATIENTS AND METHODS: Fifty-one patients with primary stage I non-small-cell lung cancer (NSCLC; n = 26), recurrent lung cancer after definitive treatment (n = 12), or solitary lung metastases (n = 13) were treated with SBRT between 2005 and 2007. Patients were treated with the CyberKnife Robotic Radiosurgery System with Synchrony respiratory tracking. A dose of 60 Gy was delivered in 3 fractions. All patients had CT or PET/CT performed at approximately 3-month intervals after treatment. RESULTS: The median follow-up was 12 months. Local control at median follow-up was 85% in patients with stage I NSCLC, 92% in patients with recurrent lung cancer, and 62% in the patients with solitary lung metastasis. Analysis of the 28 patients with pre- and post-treatment PET/CT scans demonstrated that those with stable disease (n = 4) had a mean standardized uptake value (SUV) decrease of 28%, partial responders (n = 11) had a decrease of 48%, and patients with a complete response (n = 11) had a decrease of 94%. Patients with progressive disease (n = 2) had an SUV decrease of only 0.4%. Only 2 patients (7%) who had reduced fluorodeoxyglucose avidity later progressed locally. No correlations were found between pretreatment SUV and tumor response, disease progression, or survival. Overall 1-year survival rates were 81%, 67%, and 85% among the patients with primary NSCLC, recurrent lung cancer, and solitary lung metastases, respectively. CONCLUSION: Stereotactic body radiation therapy with CyberKnife is an effective treatment for patients with medically inoperable recurrent or metastatic lung cancer. Positron emission tomography/CT is valuable in staging, planning, and evaluating treatment response and might predict long-term outcome.

Stereotactic radiosurgery for early stage non-small cell lung cancer: rationale, patient selection, results, and complications.

Lung cancer is the most common cause of cancer-related mortality in the United States. Lobectomy is the current standard of care for early stage lung cancer. For nonoperative candidates, standard radiation has been offered but generally with little hope for cure. Advanced radiation techniques with three-dimensional planning, multiple beam paths, and respiratory-motion compensation have resulted in the ability to administer high-dose radiation or stereotactic radiosurgery to lung tumors. Stereotactic radiosurgery is likely to be more effective than standard external beam radiation and there is evidence that in appropriately selected medically inoperable patients such therapy may offer a chance for cure. Early results are encouraging but these results are not mature and, recently, severe late toxicity has been reported. Prospective trials are underway in our institution and others to evaluate stereotactic radiosurgery for early stage lung neoplasm. This article summarizes the role of stereotactic radiosurgery for the treatment of lung cancer.

Clinical assessment of stereotactic IGRT: spinal radiosurgery.

The role of stereotactic radiosurgery for the treatment of intracranial lesions is well established. Its use for the treatment of spinal lesions has been limited because of the availability of effective target immobilization devices. Recent advances in stereotactic IGRT have allowed for spinal applications. Large clinical experience with spinal radiosurgery to properly assess clinical outcomes has previously been limited. At our institution, we have developed a successful multidisciplinary spinal radiosurgery program in which 542 spinal lesions (486 malignant and 56 benign lesions) were treated with a single-fraction radiosurgery technique. Patient ages ranged from 18 to 85 years (mean 56 years). Lesion location included 92 cervical, 234 thoracic, 130 lumbar, and 86 sacral. The most common metastatic tumors were renal cell (89 cases), breast (74 cases), and lung (71 cases). The most common benign tumors were neurofibroma (24 cases), schwannoma (13 cases), and meningioma (7 cases). Eighty-nine cervical lesions were treated using skull tracking. Thoracic, lumbar, and sacral tumors were tracked relative to either gold or stainless steel fiducial markers. The maximum intratumoral dose ranged from 12.5 to 30 Gy (mean 20 Gy). Tumor volume ranged from 0.16 to 298 mL (mean 47 mL). Three hundred thirty-seven lesions had received prior external beam irradiation with spinal cord doses precluding further conventional irradiation. The primary indication for radiosurgery was pain in 326 cases, as a primary treatment modality in 70 cases, for tumor radiographic tumor progression in 65 cases, for post-surgical treatment in 38 cases, for progressive neurological deficit in 35 cases, and as a radiation boost in 8 cases. Follow-up period was at least 3 to 49 months. Axial and/or radicular pain improved in 300 of 326 cases (92%). Long-term tumor control was demonstrated in 90% of lesions treated with radiosurgery as a primary treatment modality and in 88% of lesions treated for radiographic tumor progression. Thirty of 35 patients (85%) with progressive neurological deficits experienced at least some improvement after treatment. Spinal stereotactic radiosurgery is now a feasible, safe, and clinically effective technique for the treatment of a variety of spinal lesions. The potential benefits of radiosurgical ablation of spinal lesions are short treatment time in an outpatient setting with essentially no recovery time and excellent symptomatic response. This technique offers a new therapeutic modality for the primary treatment of a variety of spinal lesions, including the treatment of neoplasms in medically inoperable patients, previously irradiated sites, for lesions not amenable to open surgical techniques, and as an adjunct to surgery.