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.
To assess the outcomes of a cohort of bone oligometastatic prostate cancer patients treated with PSMA-PET guided stereotactic body radiotherapy (SBRT). From April 2017 to January 2021, 40 patients ...with oligorecurrent prostate cancer detected by PSMA-PET were treated with SBRT for bone oligometastases. Concurrent androgen deprivation therapy was an exclusion criterion. A total of 56 prostate cancer bone oligometastases were included in the present analysis. In 28 patients (70%), oligometastatic disease presented as a single lesion, two lesions in 22.5%, three lesions in 5%, four lesions in 2.5%. 30.3% were spine-metastases, while 69.7% were non-spine metastases. SBRT was delivered for a median dose of 30 Gy (24–40 Gy) in 3–5 fractions, with a median EQD
2
= 85 Gy
2
(64.3—138.9Gy
2
). With a median follow-up of 22 months (range 2–48 months), local control (LC) 1- and 2-years rates were 96.3% and 93.9%, while distant progression-free survival (DPFS) rates were 45.3% and 27%. At multivariate analysis, the lower PSA nadir value after SBRT remained significantly related to better DPFS rates (p = 0.03). In 7 patients, a second SBRT course was proposed with concurrent ADT, while 11 patients, due to polymetastatic spread, received ADT alone, resulting in 1- and 2-years ADT-free survival rates of 67.5% and 61.8%. At multivariate analysis, a lower number of treated oligometastases maintained a correlation with higher ADT-free survival rates (p = 0.04). In our experience, PSMA-PET guided SBRT resulted in excellent results in terms of clinical outcomes, representing a helpful tool with the aim to delay the start of ADT.
The constantly increasing life expectancy is raising the issue of treating oncological older patients, who were traditionally candidates to best supportive care or palliative treatments. Several ...literature data support SBRT in the treatment of the oligometastatic patient as a potentially curable therapeutic option. However, data on older patients are lacking. This study presents the outcomes of a cohort of 61 oligometastatic patients over the age of 80 years who received SBRT, that was proposed to all patients with a minimum Karnofsky Performance Status ≥ 70 and a life expectancy of at least 6 months, with up to five oligometastatic lesions. Radiotherapy was delivered in 3–10 fractions with VMAT-IGRT technique. Toxicity was retrospectively collected according to CTCAE v4.0. Data were retrospectively collected and analyzed. Univariate and multivariate analysis were performed for assessing any potential predictive factor for clinical outcomes. A total of 90 oligometastases were treated in 61 patients with median age 82 years (range, 80–90). The most frequent histology was colorectal cancer (27% of cases). Median follow-up was 20 months (range, 2–63). Local control rates at 1- and 2-years were 98.8% and 88.2%, with colorectal histology being associated with worse LC rates (
p
= 0.014) at univariate analysis. Progression-free survival rates at 1- and 2-years were 48.6% and 30.5%. Oligorecurrent lesions and single oligometastases were associated with better PFS rates (respectively,
p
= 0.04 and
p
= 0.011). Overall survival rates were 75% and 60.5%, polymetastatic spread being predictive of worse survival outcomes at multivariate analysis (
p
= 0.012). No G2 or higher adverse events were recorded. Our study supports the role of SBRT for the treatment of elderly oligometastatic patients, highlighting the possibility to further explore this therapeutic option in the management of older oncological patients.
Aim
This study aims to compare acute toxicity of prostate cancer (PCa) stereotactic body radiotherapy (SBRT) delivered by MR-guided radiotherapy (MRgRT) with 1.5-T MR-linac or by volumetric modulated ...arc (VMAT) with conventional linac.
Methods
Patients with low-to-favorable intermediate risk class PCa were treated with exclusive SBRT (35 Gy in five fractions). Patients treated with MRgRT were enrolled in an Ethical Committee (EC) approved trial (Prot. n° 23,748), while patients treated with conventional linac were enrolled in an EC approved phase II trial (n° SBRT PROG112CESC). The primary end-point was the acute toxicity. Patients were included in the analysis if they had at least 6 months of follow-up for the primary end-point evaluation. Toxicity assessment was performed according to CTCAE v5.0 scale. International Prostatic Symptoms Score (IPSS) was also performed.
Results
A total of 135 patients were included in the analysis. Seventy-two (53.3%) were treated with MR-linac and 63 (46.7%) with conventional linac. The median initial PSA before RT was 6.1 ng/ml (range 0.49–19). Globally, acute G1, G2, and G3 toxicity occurred in 39 (28.8%), 20 (14.5%), and 5 (3.7%) patients. At the univariate analysis, acute G1 toxicity did not differ between MR-linac and conventional linac (26.4% versus 31.8%), as well as G2 toxicity (12.5% versus 17.5%;
p
= 0.52). Acute G2 gastrointestinal (GI) toxicity occurred in 7% and 12.5% of cases in MR-linac and conventional linac group, respectively (
p
= 0.06), while acute G2 genitourinary toxicity occurred in 11% and 12.8% in MR-linac and conventional linac, respectively (
p
= 0.82). The median IPSS before and after SBRT was 3 (1–16) and 5 (1–18). Acute G3 toxicity occurred in two cases in the MR-linac and three cases in the conventional linac group (
p
= n.s.).
Conclusion
Prostate SBRT with 1.5-T MR-linac is feasible and safe. Compared to conventional linac, MRgRT might to potentially reduce the overall G1 acute toxicity at 6 months, and seems to show a trend toward a lower incidence of grade 2 GI toxicity. A longer follow-up is necessary to assess the late efficacy and toxicity.
Background
The use of stereotactic radiotherapy (SBRT) for oligometastases is supported by several literature studies, but in the setting of gynecological malignancies, this scenario remains quite ...unexplored. This study reports a preliminary assessment of clinical outcomes in a cohort of 40 patients with oligometastatic gynecological neoplasms.
Methods
Radiotherapy was delivered in 3–10 fractions with VMAT-IGRT technique. Toxicity was retrospectively collected according to CTCAE v4.0. Data were retrospectively collected and analyzed. Univariate and multivariate analyses were performed for assessing any potential predictive factor for clinical outcomes.
Results
A total of 63 oligometastases were treated from December 2014 to February 2021. Median age was 63 years (range 30–89). Most frequent primary tumors were ovarian cancer in 42.5% and endometrium cancer in 42.5%. With a median follow-up of 27 months (range 6–69), no local failures were observed, our progression-free survival rates were 43.6% and 23% at one and 2 years, respectively, while 1 and 2-year overall survival rates were both 70%. No acute or late G ≥ 2 adverse events were observed.
Conclusions
In our experience, SBRT for oligometastatic gynecological malignancies resulted in promising results in terms of clinical outcomes, with excellent local control and no evidence of severe toxicity, highlighting the effectiveness of this therapeutic option. Prospective studies to further explore this approach in this setting are advocated.
Stereotactic body radiotherapy (SBRT) has a consolidated role in the treatment of bone oligometastases from prostate cancer (PCa). While the evidence for spinal oligometastases SBRT was robust, its ...role in non-spinal-bone metastases (NSBM) is not standardized. In fact, there was no clear consensus about dose and target definition in this setting. The aim of our study was to evaluate efficacy, toxicity, and the pattern of relapse in SBRT delivered to NSBM from PCa.
From 2016 to 2021, we treated a series of oligo-NSBM from PCa with
Ga-PSMA PET/CT-guided SBRT. The primary endpoint was local progression-free survival (LPFS). The secondary endpoints were toxicity, the pattern of intraosseous relapse, distant progression-free survival (DPFS), polimetastases-free survival (PMFS), and overall survival (OS).
a total of 150 NSBM in 95 patients were treated with 30-35 Gy in five fractions. With a median follow-up of 26 months, 1- and 3 years LPFS was 96.3% and 89%, respectively. A biologically effective dose (BED) ≥ 198 Gy was correlated with improved LPFS (
= 0.007). Intraosseous relapse occurred in eight (5.3%) cases. Oligorecurrent disease was associated with a better PMFS compared to de novo oligometastatic disease (
= 0.001) and oligoprogressive patients (
= 0.007). No grade ≥ 3 toxicity occurred.
SBRT is a safe and effective tool for NSBM from PCa in the oligometastatic setting. Intraosseous relapse was a relatively rare event. Predictive factors of the improved outcomes were defined.
Background
Stereotactic radiotherapy (SRT) and Proton therapy (PT) are both options in the management of liver lesions. Limited clinical-dosimetric comparison are available. Moreover, dose-constraint ...routinely used in liver PT and SRT considers only the liver spared, while optimization strategies to limit the liver damaged are poorly reported.
Methods
Primary endpoint was to assess and compare liver sparing of four contemporary RT techniques. Secondary endpoints were freedom from local recurrence (FFLR), overall survival (OS), acute and late toxicity. We hypothesize that Focal Liver Reaction (FLR) is determined by a similar biologic dose. FLR was delineated on follow-up MRI. Mean C.I. was computed for all the schedules used. A so-called Fall-off Volume (FOV) was defined as the area of healthy liver (liver-PTV) receiving more than the isotoxic dose. Fall-off Volume Ratio (FOVR) was defined as ratio between FOV and PTV.
Results
213 lesions were identified. Mean best fitting isodose (isotoxic doses) for FLR were 18Gy, 21.5 Gy and 28.5 Gy for 3, 5 and 15 fractions. Among photons, an advantage in terms of healthy liver sparing was found for Vmat FFF with 5mm jaws (
p
= 0.013) and Cyberknife (
p
= 0.03). FOV and FOVR resulted lower for PT (
p
< 0.001). Three years FFLR resulted 83%. Classic Radiation induced liver disease (RILD, any grade) affected 2 patients.
Conclusions
Cyberknife and V-MAT FFF with 5mm jaws spare more liver than V-MAT FF with 10 mm jaws. PT spare more liver compared to photons. FOV and FOVR allows a quantitative analysis of healthy tissue sparing performance showing also the quality of plan in terms of dose fall-off.
The purpose of this multi-centric work was to investigate the relationship between radiomic features extracted from pre-treatment computed tomography (CT), positron emission tomography (PET) imaging, ...and clinical outcomes for stereotactic body radiation therapy (SBRT) in early-stage non-small cell lung cancer (NSCLC). One-hundred and seventeen patients who received SBRT for early-stage NSCLC were retrospectively identified from seven Italian centers. The tumor was identified on pre-treatment free-breathing CT and PET images, from which we extracted 3004 quantitative radiomic features. The primary outcome was 24-month progression-free-survival (PFS) based on cancer recurrence (local/non-local) following SBRT. A harmonization technique was proposed for CT features considering lesion and contralateral healthy lung tissues using the LASSO algorithm as a feature selector. Models with harmonized CT features (B models) demonstrated better performances compared to the ones using only original CT features (C models). A linear support vector machine (SVM) with harmonized CT and PET features (A1 model) showed an area under the curve (AUC) of 0.77 (0.63–0.85) for predicting the primary outcome in an external validation cohort. The addition of clinical features did not enhance the model performance. This study provided the basis for validating our novel CT data harmonization strategy, involving delta radiomics. The harmonized radiomic models demonstrated the capability to properly predict patient prognosis.
•There is no clear evidence on the best treatment after primary SRS to brain metastases.•SRS might be an effective approach with the aim to defer or avoid WBRT.•We reported a series of patients ...treated with repeated monoisocentric SRS technique.•We showed high local control levels and acceptable survival.•95 % of new intracranial relapses after SRS occurred to brain tissue receiving ≤ 7 Gy.
Evaluate effectiveness and safety of multiple HyperArc courses and patterns of progression in patients affected by BMs with intracranial progression.
56 patients were treated for 702 BMs with 197 (range 2–8) HyperArc courses in case of exclusive intracranial progression. Primary end-point was the overall survival (OS), secondary end-points were intracranial progression-free survival (iPFS), toxicity, local control (LC), neurological death (ND), and whole-brain RT (WBRT)-free survival. Site of progression was evaluated against isodoses levels (0, 1, 2, 3, 5, 7, 8, 10, 13, 15, 20, and 24 Gy.).
The 1-year OS was 70 %, and the median was 20.8 months (17–36). At the univariate analysis (UVA) biological equivalent dose (BED) > 51.3 Gy and non-melanoma histology significantly correlated with OS. The median time to iPFS was 4.9 months, and the 1-year iPFS was 15 %. Globally, 538 new BMs occurred after the first HA cycle in patients with extracranial disease controlled. 96.4 % of them occurred within the isodoses range 0–7 Gy as follows: 26.6 % (0 Gy), 16.5 % (1 Gy), 16.5 % (2 Gy), 20.1 % (3 Gy), 13.1 % (5 Gy), 3.4 % (7 Gy) (p = 0.00). Radionecrosis occurred in 2 metastases (0.28 %). No clinical toxicity of grade 3 or higher occurred during follow-up. One- and 2-year LC was 90 % and 79 %, respectively. At the UVA BED > 70 Gy and non-melanoma histology were significant predictors of higher LC. The 2-year WBRT-free survival was 70 %. After a median follow-up of 17.4 months, 12 patients deceased by ND.
Intracranical relapses can be safely and effectively treated with repeated HyperArc, with the aim to postpone or avoid WBRT. Diffuse dose by volumetric RT might reduce microscopic disease also at relatively low levels, potentially acting as a virtual CTV. Neurological death is not the most common cause of death in this population, which highlights the impact of extracranial disease on overall survival.
Background : Lymph-nodal prostate cancer oligometastases are differently treated according to their site: pelvic are locoregional lymph nodes; instead, para-aortic lymph nodes are considered as ...distant metastases. The aim of the study was a comparison between para-aortic and pelvic oligometastases treated with stereotactic body radiation therapy (SBRT). Methods : This is a retrospective analysis. De novo metastatic or extra-nodal disease were excluded. Univariate and multivariate analyses were performed; the pattern of recurrence was also evaluated. A propensity score matching (PSM) was applied to create comparable cohorts. The primary end-point was the progression-free survival (PFS). The secondary end-points were biochemical relapse-free survival (BRFS), ADT-free survival (ADTFS), polymetastases-free survival (PMFS), local progression-free survival (LPFS), and pattern of relapse. Results : In total, 240 lymph-nodal oligometastases in 164 patients (127 pelvic and 37 para-aortic) were treated. The median PFS was 20 and 11 months in pelvic and para-aortic patients, respectively (p = 0.042). The difference was not confirmed in the multivariate analysis (p = 0.06). The median BRFS was 16 and 9 months, respectively, in the pelvic and para-aortic group (p = 0.07). No statistically significant differences for ADTFS or PMFS were detected. The cumulative 5-year LPFS was 90.5%. In PSM, no statistically significant differences for all the study end-points were detected. Conclusions : Patients affected by para-aortic disease might have a PFS comparable to pelvic disease; local control is high in both cohorts. Our results also support the use of SBRT for para-aortic metastases.