Unity Elekta is a unique magnetic resonance (MR)-linac that conjugates a 1.5 Tesla MR unit with a 7 MV flattening filter free accelerator.A prospective observational study for the clinical use of ...Elekta Unity is currently ongoing in our department. Herein, we present our preliminary report on the feasibility, quality of life, and patient-reported outcomes measures (PROMs) for localized prostate cancer (PC) treated with stereotactic body radiotherapy (SBRT).
The SBRT protocol consisted of a 35 Gy schedule delivered in 5 fractions within 2 weeks. Toxicity and quality of life (QoL) were assessed at baseline and after treatment using the Common Terminology Criteria for Adverse Events v5.0, International Prostatic Symptoms Score (IPSS), ICIQ-SF, IIEF-5, and EORTC-QLQ-C30 and PR-25 questionnaires.
Between October 2019 and January 2020, 25 patients with localized PC were recruited. The median age was 68 years (range, 54-82); 4 were low risk, 11 favorable intermediate risk (IR) and 10 unfavorable IR. Median iPSA was 6.8 ng/ml (range, 1-19), and 9 of these patients (36%) received concurrent androgen deprivation therapy. Median prostate volume was 36 cc (range, 20-61); median baseline IPSS was 5 (range, 0-10). Median time for fraction was 53 min (range, 34-86); adaptive strategy with daily critical structure and target re-contouring and daily replanning (adapt to shape) was performed in all cases. No grade ≥ 3 adverse event was observed, three patients (12%) reported grade 2 acute genitourinary toxicity (urinary frequency, urinary tract pain and urinary retention), while only one patient reported mild rectal pain. No relevant deteriorations were reported in PROMs.
To the best of our knowledge, this is the first experience reporting feasibility, clinician-reported outcome measurements, and PROMs for 1.5 T MR-guided adaptive SBRT for localized prostate cancer. The preliminary data collected here report optimal safety and excellent tolerability, as also confirmed by PROMs questionnaires. Moreover, the data on technical feasibility and timing of online daily adapted planning and delivery are promising. More mature data are warranted.
Date of approval April 2019 and numbered MRI/LINAC n°23,748.
Purpose
SBRT demonstrated to increase survival in oligometastatic patients. Nevertheless, little is known regarding the natural history of oligometastatic disease (OMD) and how SBRT may impact the ...transition to the polymetastatic disease (PMD).
Methods
97 liver metastases in 61 oligometastatic patients were treated with SBRT. Twenty patients (33%) had synchronous oligometastases, 41 (67%) presented with metachronous oligometastases. Median number of treated metastases was 2 (range 1–5).
Results
Median follow-up was 24 months. Median tPMC was 11 months (range 4–17 months). Median overall survival (OS) was 23 months (range 16–29 months). Cancer-specific survival predictive factors were having further OMD after SBRT (21 months versus 15 months;
p
= 0.00), and local control of treated metastases (27 months versus 18 months;
p
= 0.031). Median PFS was 7 months (range 4–12 months). Patients with 1 metastasis had longer median PFS as compared to those with 2–3 and 4–5 metastases (14.7 months versus 5.3 months versus 6.5 months;
p
= 0.041). At the last follow-up, 50/61 patients (82%) progressed, 16 of which (26.6%) again as oligometastatic and 34 (56%) as polymetastatic.
Conclusion
In the setting of oligometastatic disease, SBRT is able to delay the transition to the PMD. A proportion of patients relapse as oligometastatic and can be eventually evaluated for a further SBRT course. Interestingly, those patients retain a survival benefit as compared to those who had PMD. Further studies are needed to explore the role of SBRT in OMD and to identify treatment strategies able to maintain the oligometastatic state.
The main aim of the current analysis was to explore the hypothetical advantages using rectal spacer during 1.5T MR-guided and daily adapted prostate cancer stereotactic body radiotherapy (SBRT) ...compared to a no-rectal spacer hydrogel cohort of patients.
The SBRT-protocol consisted of a 35 Gy schedule delivered in 5 fractions. Herein, we present a dosimetric analysis between spacer and no-spacer patients. Furthermore, treatment tolerability and feasibility were preliminarily assessed according to clinicians-reported outcomes at the end of treatment and patient-reported outcomes measures (PROMs) in both arms. Toxicity and quality of life were assessed at baseline and after treatment using the Common Terminology Criteria for Adverse Events v. 5.0, International Prostatic Symptoms Score, ICIQ-SF, IIEF-5, and EORTC-QLQ-C30 and PR-25 questionnaires.
120 plans (pre- and daily adaptive SBRT planning) were analyzed in 20 patients (10 patients in spacer group and 10 patients in no-spacer group) treated using 1.5T MR-guided adaptive SBRT. Statistically significant dosimetric advantages were observed in favor of the spacer insertion, improving the planning target volume coverage in terms of V33.2Gy >95% and planning target volume 37.5 Gy <2% mainly during daily-adapted SBRT. Also, rectum V32, V28 and V18Gy and bladder V35Gy <1 cc were significantly reduced in the spacer cohort. Concerning the PROMS, all questionnaires showed no difference between the pre- and post-SBRT evaluation in both arms, excepting the physical functioning item of EORTC QLQ-C30 questionnaire that was declined in the no-spacer group.
These preliminary results strongly suggest the adoption of perirectal spacer due to dosimetric advantages not only for rectal sparing but also for target coverage. Longer follow-up is required to validate the clinical impact in terms of clinicians-reported toxicity and PROMs.
This the first experience reporting preliminary data concerning the potential dosimetric impact of rectal hydrogel spacer on MR-guided SBRT for prostate cancer.
Cyclin dependent kinases 4/6 (CDK4/6) inhibitors gained an essential role in the treatment of metastatic breast cancer. Nevertheless, data regarding their use in combination with radiotherapy are ...still scarce. We performed a retrospective preliminary analysis of breast cancer patients treated at our Center with palliative radiation therapy and concurrent CDK4/6 inhibitors. Toxicities were measured according to CTCAE 4.0, local response according to RECIST 1.1 or PERCIST 1.0 and pain control using verbal numeric scale. 18 patients (32 treated sites) were identified; 50% received palbociclib, 33.3% ribociclib and 16.7% abemacliclib. Acute non-hematologic toxicity was fair, with the only exception of a patient who developed G3 ileitis. During 3 months following RT, 61.1% of patients developed G 3-4 neutropenia; nevertheless no patient required permanent suspension of treatment. Pain control was complete in 88.2% of patients three months after radiotherapy; 94.4% of patients achieved and maintained local control of disease. Radiotherapy concomitant to CDK4/6 inhibitors is feasible and characterized by a fair toxicity profile, with isolated episodes of high-grade reversible intestinal toxicity. Rate of G 3-4 neutropenia was comparable with that measured for CDK4/6 inhibitors alone. Promising results were reported in terms of pain relief and local control of disease.
During the natural history of oncologic diseases, approximately 20-40% of patients affected by cancer will develop brain metastases. Non-small lung cancer, breast cancer, and melanoma are the ...primaries that are most likely to metastasize into the brain. To date, the role of Radiosurgery/Stereotactic Radiotherapy (SRS/SRT) without Whole brain irradiation (WBRT) is a well-recognized treatment option for patients with limited intracranial disease (1-4 BMs) and a life-expectancy of more than 3-6 months. In the current review, we focused on randomized studies that evaluate the potential benefit of radiosurgery/stereotactic radiotherapy for brain oligometastases. To date, no difference in overall survival has been observed between SRS/SRT alone compared to WBRT plus SRS. Notably, SRS alone achieved higher local control rates compared to WBRT. A possible strength of SRS adoption is the potential decreased neurocognitive impairment.
Background
We present preliminary data of the first older cancer patients treated with Hybrid Linac for stereotactic body radiotherapy (SBRT) consisting of 1.5 T MRI-guided and daily-adapted ...treatment. The aim was to assess feasibility, safety and the role of G8 and Charlson Comorbidity Index (CCI) questionnaires in predicting patients’ QoL, evaluated by patient-reported outcome measures (PROMs).
Methods
Two groups of patients with localized prostate cancer or abdominal-pelvic oligometastases were analyzed. SBRT schedule consisted of 35 Gy delivered in 5 fractions. The primary endpoint was to measure the impact of G8 and CCI on PROMs. Both G8 and the CCI were performed at baseline, while the EORTC Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) for PROMs assessment was prospectively performed at baseline and after SBRT.
Results
Forty older patients were analyzed. The median age was 73 years (range 65–85). For the entire population, the median G8 score was 15 (10–17) and the median CCI score was 6 (4–11). Concerning the PROMS, the EORTC-QLQ C30 questionnaire reported no difference between the pre- and post-SBRT evaluation in all patients, except for the fatigue item that declined after SBRT, especially in the group of patients with a G8 score < 15 and with age < 75 years (
p
= 0.049). No grade 3 or higher acute toxicity occurred.
Conclusion
This is the first report documenting for older cancer patients that 1.5 T MRI-guided daily-adapted SBRT is feasible, safe and does not impact on the QoL at the end of treatment. Longer follow-up is advocated to report long-term outcomes.
Trial registration
Date of approval April 2019 and numbered MRI/LINAC no. 23748.
Purpose
Aim of this study is to assess the ability of contrast-enhanced CT image-based radiomic analysis to predict local response (LR) in a retrospective cohort of patients affected by pancreatic ...cancer and treated with stereotactic body radiation therapy (SBRT). Secondary aim is to evaluate progression free survival (PFS) and overall survival (OS) at long-term follow-up.
Methods
Contrast-enhanced-CT images of 37 patients who underwent SBRT were analyzed. Two clinical variables (BED, CTV volume), 27 radiomic features were included. LR was used as the outcome variable to build the predictive model. The Kaplan–Meier method was used to evaluate PFS and OS.
Results
Three variables were statistically correlated with the LR in the univariate analysis: Intensity Histogram (StdValue feature), Gray Level Cooccurrence Matrix (GLCM25_Correlation feature) and Neighbor Intensity Difference (NID25_Busyness feature). Multivariate model showed GLCM25_Correlation (
P
= 0.007) and NID25_Busyness (
P
= 0.03) as 2 independent predictive variables for LR. The odds ratio values of GLCM25_Correlation and NID25_Busyness were 0.07 (95%CI 0.01–0.49) and 8.10 (95%CI 1.20–54.40), respectively. The area under the curve for the multivariate logistic regressive model was 0.851 (95%CI 0.724–0.978). At a median follow-up of 30 months, median PFS was 7 months (95%CI 6-NA); median OS was 11 months (95%CI 10–22 months).
Conclusions
This analysis identified a radiomic signature that correlates with LR. To confirm these results, prospective studies could identify patient sub-groups with different rates of radiation dose–response to define a more personalized SBRT approach.
Purpose
We report preliminary dosimetric data concerning the use of 1.5-T MR-guided daily-adaptive radiotherapy for abdomino-pelvic lymph-nodal oligometastases. We aimed to assess the impact of this ...technology on mitigating daily variations for both target coverage and organs-at-risk (OARs) sparing.
Methods
A total of 150 sessions for 30 oligometastases in 23 patients were analyzed. All patients were treated with MR-guided stereotactic body radiotherapy (SBRT) for a total dose of 35 Gy in five fractions. For each fraction, a quantitative analysis was performed for PTV volume, V35Gy and
D
mean
. Similarly, for OARs, we assessed daily variations of volume,
D
mean
,
D
max
. Any potential statistically significant change between baseline planning and daily-adaptive sessions was assessed using the Wilcoxon signed-rank test, assuming a
p
value < 0.05 as significant.
Results
Average baseline PTV, bowel, bladder, and single intestinal loop volumes were respectively 8.9 cc (range 0.7–41.2 cc), 1176 cc (119–3654 cc), 95 cc (39.7–202.9 cc), 18.3 cc (9.1–37.7 cc). No significant volume variations were detected for PTV (
p
= 0.21) bowel (
p
= 0.36), bladder (
p
= 0.47), except for single intestinal loops, which resulted smaller (
p
= 0.026). Average baseline V35Gy and
D
mean
for PTV were respectively 85.6% (72–98.8%) and 35.6 Gy (34.6–36.1 Gy). We recorded a slightly positive trend in favor of daily-adaptive strategy vs baseline planning for improved target coverage, although not reaching statistical significance (
p
= 0.11 and
p
= 0.18 for PTV-V35Gy and PTV-
D
mean
). Concerning OARs, a significant difference was observed in favor of daily-adapted treatments in terms of single intestinal loop
D
max
23.05 Gy (13.2–26.9 Gy) at baseline vs 20.5 Gy (12.1–24 Gy);
p
value = 0.0377 and
D
mean
14.4 Gy (6.5–18 Gy) at baseline vs 13.0 Gy (6.7–17.6 Gy);
p
value = 0.0003. Specifically for bladder, the average
D
max
was 18.6 Gy (0.4–34.3 Gy) at baseline vs 18.3 Gy (0.7–34.3 Gy) for a
p
value = 0.28; the average
D
mean
was 7.0 Gy (0.2–16.6 Gy) at baseline vs 6.98 Gy (0.2–16.4 Gy) for a
p
value = 0.66. Concerning the bowel, no differences in terms of
D
mean
4.78 Gy (1.3–10.9 Gy) vs 5.6 Gy (1.4–10.5 Gy);
p
value = 0.23 were observed between after daily-adapted sessions. A statistically significant difference was observed for bowel
D
max
26.4 Gy (7.7–34 Gy) vs 25.8 Gy (7.8–33.1 Gy);
p
value = 0.0086.
Conclusions
Daily-adaptive MR-guided SBRT reported a significantly improved single intestinal loop sparing for lymph-nodal oligometastases. Also, bowel
D
max
was significantly reduced with daily-adaptive strategy. A minor advantage was also reported in terms of PTV coverage, although not statistically significant.
Abstract
Background
The assessment of organ motion is a crucial feature for prostate stereotactic body radiotherapy (SBRT). Rectal spacer may represent a helpful device in order to outdistance rectal ...wall from clinical target, but its impact on organ motion is still a matter of debate. MRI-Linac is a new frontier in radiation oncology as it allows a superior visualization of the real-time anatomy of the patient and the current highest level of adaptive radiotherapy.
Methods
We present data regarding a total of 100 fractions in 20 patients who underwent MRI-guided prostate SBRT for low-to-intermediate risk prostate cancer with or without spacer. Translational and rotational shifts were computed on the pre- and post-treatment MRI acquisitions referring to the delivery position for antero-posterior, latero-lateral and cranio-caudal direction, and assessed using the Mann-Whitney U-Test.
Results
All patients were treated with a five sessions schedule (35 Gy/5fx) using MRI-Linac for a median fraction treatment time of 50 min (range, 46–65). In the entire study sample, median rotational displacement was 0.1° in cranio-caudal, − 0.002° in latero-lateral and 0.01° in antero-posterior direction; median translational shift was 0.11 mm in cranio-caudal, − 0.24 mm in latero-lateral and − 0.22 mm in antero-posterior. A significant difference between spacer and no-spacer patients in terms of rotational shifts in the antero-posterior direction (
p
= 0.033) was observed; also for translational shifts a positive trend was detected in antero-posterior direction (
p
= 0.07), although with no statistical significance. We observed statistically significant differences in the pre-treatment planning phase in favor of the spacer cohort for several rectum dose constraints: rectum V32Gy < 5% (
p
= 0.001), V28 Gy < 10% (
p
= 0.001) and V18Gy < 35% (
p
= 0.039). Also for bladder V35 Gy < 1 cc, the use of spacer provided a dosimetric advantage compared to the no-spacer subpopulation (
p
= 0.04). Furthermore, PTV V33.2Gy > 95% was higher in the spacer cohort compared to the no-spacer one (
p
= 0.036).
Conclusion
In our experience, the application of rectal hydrogel spacer for prostate SBRT resulted in a significant impact on rotational antero-posterior shifts contributing to limit prostate intra-fraction motion. Further studies with larger sample size and longer follow-up are required to confirm this ideally favorable effect and to assess any potential impact on clinical outcomes.
Stereotactic radiosurgery (SRS) is an effective treatment option for multiple brain metastases (BMs). Modern mono-isocentric techniques allow the delivery of multiple stereotactic courses, in the ...event of intracranial failure. Nevertheless, limited data on effectiveness and toxicity have been reported in comparison to WBRT. Aim of this retrospective matched-pair analysis was to compare patients affected by limited BMs treated with multiple SRS courses using a mono-isocentric, non-coplanar technique (HyperArc™, Varian Medical System) to upfront WBRT. One hundred and two patients accounting for 677 BMs were treated with HyperArc™. In case of further intracranial progression, 44 treatment courses of 201 metastases in 19 patients, were treated by subsequent HyperArc™ courses. This population was matched with 38 patients treated with WBRT. The median BMs number was 4 (range 2–10) for HyperArc™ and 5 (range 2–10) for WBRT. Overall survival (OS) and toxicity were evaluated. The median follow-up was 9 months (range 3–40 months). The median OS was not reached (range 5–22 months) for HyperArc™ patients and 8 months (range 3–40 months) for WBRT patients, while the 1-year OS was 77% and 34.6% for HyperArc™ and WBRT, respectively (p = 0.001; HR 4.77, 95% CI 1.62–14.00). There was one case of radionecrosis. HyperArc™ is an effective and safe technique for the treatment of multiple BMs. In selected cases of intracranial oligorecurrence, further subsequent courses can be safely delivered with the same technical approach. Moreover, in patients with a limited number of BMs, SRS showed an improved survival outcome when compared to WBRT.
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