Dose-intensified stereotactic body radiotherapy for painful vertebral metastases: A randomized phase 3 trial.

BACKGROUND: The purpose of this randomised study was to determine whether dose-intensified stereotactic body radiotherapy (SBRT) for painful vertebral metastases results in increased rates of pain improvement compared with conventional external beam radiotherapy (cEBRT) (control) 6 months after treatment. METHODS: This randomized, controlled phase 3 trial was conducted between November 2016 and January 2023, when it was stopped early. Patients were eligible if they were aged 18 years or older; had one or two painful, stable, or potentially unstable vertebral metastases; and had a life expectancy of 1 year or longer according to the investigator's estimates. Patients received 48.5 grays (Gy) in 10 fractions (with epidural involvement) or 40 Gy in five fractions (without epidural involvement) in the SBRT group and 30 Gy in 10 fractions or 20 Gy in five fractions in the cEBRT group, respectively. The primary end point was an improvement in the pain score at the treated site by at least 2 points (on a visual analog scale from 0 to 10 points) at 6-month follow-up. Data were analyzed on an intention-to-treat and per-protocol basis. RESULTS: Of 214 patients who were screened for eligibility, 63 were randomized 1:1 between SBRT (33 patients with 36 metastases) and cEBRT (30 patients with 31 metastases). The median age of all patients was 66 years, and 40 patients were men (63.5%). In the intention-to-treat analysis, the 6-month proportion of patients who had metastases with pain reduction by 2 or more points was significantly higher in the SBRT group versus the control group (69.4% vs. 41.9%, respectively; two-sided p = .02). Changes in opioid medication intake relative to baseline were nonsignificant between the groups. No differences were observed in vertebral compression fracture or adverse event rates between the groups. CONCLUSIONS: Dose-intensified SBRT improved pain score more effectively than cEBRT at 6 months.

Image-guided moderately hypofractionated radiotherapy for localized prostate cancer: a multicentric retrospective study (IPOPROMISE).

BACKGROUND: Moderate hypofractionated radiotherapy is a treatment option for the cure of localized prostate cancer (PCa) patients based on the results of randomized prospective trials, but there is a clinical concern about the relatively short length of follow-up, and real-world results on outcome and toxicity based on cutting-edge techniques are lacking. The objective of this study is to present the long-term results of a large multicentric series. MATERIALS AND METHODS: We retrospectively evaluated 1325 PCa patients treated with daily volumetric image-guided hypofractionated radiotherapy between 2007 and 2020 in 16 Centers. For survival endpoints, we used Kaplan-Meier survival curves and fitted univariate and multivariable Cox's proportional hazards regression models to study the association between the clinical variables and each survival type. RESULTS: At the end of the follow-up, 11 patients died from PCa. The 15-year values of cancer-specific survival (CSS) and biochemical relapse-free survival (b-RFS) were 98.5% (95%CI 97.3-99.6%) and 85.5% (95%CI 81.9-89.4%), respectively. The multivariate analysis showed that baseline PSA, Gleason score, and the use of androgen deprivation therapy were significant variables for all the outcomes. Acute gastrointestinal (GI) and genitourinary (GU) toxicities of grade ≥ 2 were 7.0% and 16.98%, respectively. The 15-year late grade ≥ 2 GI and GU toxicities were 5% (95%CI 4-6%) and 6% (95%CI 4-8%), respectively. CONCLUSION: Real-world long-term results of this multicentric study on cutting-edge techniques for the cure of localized PCa demonstrated an excellent biochemical-free survival rate of 85.5% at 15 years, and very low rates of ≥ G3 late GU and GI toxicity (1.6% and 0.9% respectively), strengthening the results of the available published trials.

Oligorecurrent Non-Small-Cell Lung Cancer Treated by Chemo-Radiation Followed by Immunotherapy and Intracranial Radiosurgery: A Case Report and Mini Review of Literature.

Locally advanced non-small-cell lung cancer still represents a "grey zone" in terms of the best treatment choice and optimal clinical outcomes. Indeed, most patients may be suitable to receive different treatments with similar outcomes such as chemo-radiotherapy (CHT-RT) followed by immunotherapy (IO) or surgery followed by adjuvant local/systemic therapies. We report a clinical case of a patient submitted to primary thoracic surgery who developed a mediastinal nodal recurrence successfully treated by CHT-RT-IO. Subsequently, a single brain lesion was found to have been successfully treated by single fraction stereotactic ablative radiotherapy. The patient is still on follow-up and she is free from disease having a good quality of life. In this report, we also perform a mini review about the role of CHT-RT followed by IO in treating loco-regional relapse after surgery. The role of SABR after IO is also evaluated, finding that it is safe and well tolerated. More robust and larger clinical data are needed in this particular setting to better define the role of the combination of systemic and local treatments in the management of intrathoracic and intracranial relapse for patients already submitted to CHT-RT followed by immunotherapy.

Dose-escalated pelvic radiotherapy for prostate cancer in definitive or postoperative setting.

PURPOSE: Given the absence of standardized planning approach for clinically node-positive (cN1) prostate cancer (PCa), we collected data about the use of prophylactic pelvic irradiation and nodal boost. The aim of the present series is to retrospectively assess clinical outcomes after this approach to compare different multimodal treatment strategies in this scenario. METHODS: Data from clinical records of patients affected by cN1 PCa and treated in six different Italian institutes with prophylactic pelvic irradiation and boost on pathologic pelvic lymph nodes detected with CT, MRI or choline PET/CT were retrospectively reviewed and collected. Clinical outcomes in terms of overall survival (OS) and biochemical relapse-free survival (b-RFS) were explored. The correlation between outcomes and baseline features (International Society of Urological Pathology-ISUP pattern, total dose to positive pelvic nodes ≤ / > 60 Gy, sequential or simultaneous integrated boost (SIB) administration and definitive vs postoperative treatment) was explored. RESULTS: ISUP pattern < 2 was a significant predictor of improved b-RFS (HR = 0.3, 95% CI 0.1220-0.7647, P = 0.0113), while total dose < 60 Gy to positive pelvic nodes was associated with worse b-RFS (HR = 3.59, 95% CI 1.3245-9.741, P = 0.01). Conversely, treatment setting (postoperative vs definitive) and treatment delivery technique (SIB vs sequential boost) were not associated with significant differences in terms of b-RFS (HR = 0.85, 95% CI 0.338-2.169, P = 0.743, and HR = 2.39, 95% CI 0.93-6.111, P = 0.067, respectively). CONCLUSION: Results from the current analysis are in keeping with data from literature showing that pelvic irradiation and boost on positive nodes are effective approaches. Upfront surgical approach was not associated with better clinical outcomes.

Radiotherapy at oligoprogression for metastatic castration-resistant prostate cancer patients: a multi-institutional analysis.

PURPOSE: To retrospectively estimate the impact of radiotherapy as a progression-directed therapy (PDT) in oligoprogressive metastatic castration-resistant prostate cancer (mCRPC) patients under androgen receptor-target therapy (ARTT). MATERIALS AND METHODS: mCRPC patients are treated with PDT. End-points were time to next-line systemic treatment (NEST), radiological progression-free survival (r-PFS) and overall survival (OS). Toxicity was registered according to Common Terminology Criteria for Adverse Events v4.0. Survival analysis was performed using the Kaplan-Meier method; univariate and multivariate analyses were performed. RESULTS: Fifty-seven patients were analyzed. The median follow-up after PDT was 25.2 months (interquartile, 17.1-44.5). One-year NEST-free survival, r-PFS and OS were 49.8%, 50.4% and 82.1%, respectively. At multivariate analysis, polymetastatic condition at diagnosis of metastatic hormone-sensitive prostate cancer (mHSPC) (HR 2.82, p = 0.004) and PSA doubling time at diagnosis of mCRPC (HR 2.76, p = 0.006) were associated with NEST-free survival. The same variables were associated with r-PFS (HR 2.32, p = 0.021; HR 2.24, p = 0.021). One patient developed late grade ≥ 2 toxicity. CONCLUSION: Our study shows that radiotherapy in oligoprogressive mCRPC is safe, is effective and seems to prolong the efficacy of ARTT in patients who otherwise would have gone systemic treatment switch, positively affecting disease progression. Prospective trials are needed.

Stereotactic or conventional radiotherapy for macroscopic prostate bed recurrence: a propensity score analysis.

PURPOSE: To assess outcomes between salvage radiation therapy (SRT) with curative intent and stereotactic radiotherapy for macroscopic prostate recurrence (SSRT) after radical prostatectomy (RP). In order to compare these two different options, we compared their outcomes with a propensity score-based matched analysis. METHODS: Data from 185 patients in seven Italian centres treated for macroscopic prostate bed recurrence after RP were retrospectively collected. To make a comparison between the two treatment groups, propensity matching was applied to create comparable cohorts. RESULTS: After matching, 90 patients in the SRT and SSRT groups were selected (45 in each arm). Kaplan-Meier analysis did not show any significant differences in terms of BRFS and PFS between matched populations (p = 0.08 and p = 0.8, respectively). Multivariate models show that treatment was not associated with BRFS, neither in the whole or matched cohort, with HR of 2.15 (95%CI 0.63-7.25, p = 0.21) and 2.65 (95%CI 0.59-11.97, p = 0.21), respectively. In the matched cohort, lower rate of toxicity was confirmed for patients undergoing SSRT, with acute GI and GU adverse events reported in 4.4 versus 44.4% (p < 0.001) and 28.9 versus 46.7% (p = 0.08) of patients, and late GI and GU adverse events reported in 0 versus 13.3% (p = 0.04) and 6.7 versus 22.2% (p = 0.03) of patients, respectively. CONCLUSION: Considering the favourable therapeutic ratio of this approach and the lower number of fractions needed, SSRT should be considered as an attractive alternative to conventional SRT in this setting.

Dissecting Immunotherapy Strategies for Small Cell Lung Cancer: Antibodies, Ionizing Radiation and CAR-T.

Small cell lung cancer (SCLC) is a highly aggressive malignancy that accounts for about 14% of all lung cancers. Platinum-based chemotherapy has been the only available treatment for a long time, until the introduction of immune checkpoint inhibitors (ICIs) recently changed first-line standard of care and shed light on the pivotal role of the immune system. Despite improved survival in a subset of patients, a lot of them still do not benefit from first-line chemo-immunotherapy, and several studies are investigating whether different combination strategies (with both systemic and local treatments, such as radiotherapy) may improve patient outcomes. Moreover, research of biomarkers that may be used to predict patients' outcomes is ongoing. In addition to ICIs, immunotherapy offers other different strategies, including naked monoclonal antibodies targeting tumor associated antigens, conjugated antibody, bispecific antibodies and cellular therapies. In this review, we summarize the main evidence available about the use of immunotherapy in SCLC, the rationale behind combination strategies and the studies that are currently ongoing in this setting, in order to give the reader a clear and complete view of this rapidly expanding topic.

Sequential chemo-hypofractionated RT versus concurrent standard CRT for locally advanced NSCLC: GRADE recommendation by the Italian Association of Radiotherapy and Clinical Oncology (AIRO).

INTRODUCTION: Almost 30% of non-small cell lung cancer (NSCLC) patients have locally advanced-stage disease. In this setting, definitive radiotherapy concurrent to chemotherapy plus adjuvant immunotherapy (cCRT + IO) is the standard of care, although only 40% of these patients are eligible for this approach. AIMS: A comparison between cCRT and hypofractionated radiotherapy regimens (hypo-fx RT) with the addition of sequential chemotherapy (sCHT) could be useful for future combinations with immunotherapy. We developed a recommendation about the clinical question of whether CHT and moderately hypo-fx RT are comparable to cCRT for locally advanced NSCLC MATERIALS AND METHODS: The panel used GRADE methodology and the Evidence to Decision (EtD) framework. After a systematic literature search, five studies were eligible. We identified the following outcomes: progression-free survival (PFS), overall survival (OS), freedom from locoregional recurrence (FFLR), deterioration of quality of life (QoL), treatment-related deaths, severe G3-G4 toxicity, late pulmonary toxicity G3-G4, and acute esophageal toxicity G3-G4. RESULTS: The probability of OS and G3-G4 late lung toxicity seems to be worse in patients submitted to sCHT and hypo-fx RT. The panel judged unfavorable the balance benefits/harms. CONCLUSIONS: The final recommendation was that sCHT followed by moderately hypo-fx RT should not be considered as an alternative to cCRT in unresectable stage III NSCLC patients.

Whole breast external beam radiotherapy in elderly patients affected by left-sided early breast cancer: a dosimetric comparison between two simple free-breathing techniques.

BACKGROUND: Elderly breast cancer patients are frequently affected by significant comorbidities that make sophisticated radiotherapy treatments particularly challenging. AIMS: We dosimetrically analyzed two different simple free-breathing external beam radiotherapy (EBRT) techniques for the hypofractionated treatment of the left breast in elderly patients with a low compliance, to compare target coverage, and heart and left anterior descending coronary artery (LADCA) sparing. METHODS: We developed radiation plans for 24 elderly patients using 3D conformal (3DCRT) field-in-field tangential technique and intensity-modulated (IMRT) tangential beam technique. Dose-Volume-Histograms (DVHs) were used to provide a quantitative comparison between plans. RESULTS: The median breast volume was 645 cm3. IMRT and 3DCRT plans comparison demonstrated no significant differences in terms of organ sparing for the heart. Regarding LADCA, mean dose (10.3 ± 9.5 Gy vs 11.9 ± 9.6 Gy, p = 0.0003), maximum dose (26.1 ± 16.1 Gy vs 29.1 ± 16.1 Gy, p = 0.004) and V17 Gy (21.5% ± 26.9% vs 25.0% ± 27.2%, p = 0.002) significantly decreased using IMRT compared with 3DCRT. IMRT plans showed a better target coverage compared with 3DCRT (0.91 ± 0.05 vs 0.93 ± 0.04, p = 0.05). DISCUSSION: Comparing the two different EBRT techniques, we demonstrated few, although substantial, dosimetric differences in terms of doses to the organs at risk characterized by a statistically significant dose reduction of LADCA in the IMRT plans. CONCLUSIONS: Elderly patients with a low compliance to treatment might benefit from 3DCRT with field-in-field tangential arrangement or from a simple IMRT approach. IMRT should be preferred.

Is multidisciplinary management possible in the treatment of lung cancer? A report from three Italian meetings.

PURPOSE: To report criticisms and barriers to the "real-life" application of international guidelines and recent developments in the management of locally advanced non-small cell lung cancer (NSCLC) in Italy. METHODS: Three 2-day courses were organized. During the first day, experts in different fields of thoracic oncology gave their lecture on diagnosis and therapy for locally advanced NSCLC. During the second day, all participants were divided into four groups to discuss on a clinical case as a multidisciplinary team (MDT). The aim was to stimulate the discussion on practical issues in the management of NSCLC patients in the real-life practice. RESULTS: A total of 196 physicians were involved in the courses as learners. Invasive diagnosis of nodal disease for staging purposes, a priori definition of "surgical resectability" and a regular MDT with all crucial participants available were the three main key points identified for a good management of these patients. The main barriers to the clinical application of a good diagnostic and therapeutic approach to the patient were the absence of a regular and complete MDT in the South and Centre of Italy, while in the North of Italy, time for discussion of clinical cases in the MDT and waiting lists for staging and therapeutic interventions were deemed as the major concerns. CONCLUSION: The meetings showed that diagnosis and treatment of locally advanced NSCLC are still extremely variable between different Italian regions. Logistic issues, waiting lists, paucity of well-trained staff and expertise seem to be the main barriers to international guidelines application.

Hypofractionated radiation therapy versus chemotherapy with temozolomide in patients affected by RPA class V and VI glioblastoma: a randomized phase II trial.

INTRODUCTION: In RPA V-VI glioblastoma patients both hypofractionated radiotherapy and exclusive temozolomide can be used; the purpose of this trial is to compare these treatment regimens in terms of survival and quality of life. METHODS: Patients with histologic diagnosis of glioblastoma were randomized to hypofractionated radiotherapy (RT-30 Gy in 6 fractions) and exclusive chemotherapy (CHT-emozolomide 200 mg/m2/day 5 days every 28 days). Overall (OS) and progression free survival (PFS) were evaluated with Kaplan Maier curves and correlated with prognostic factors. Quality- adjusted survival (QaS) was evaluated according to the Murray model (Neurological Sign and Symptoms-NSS) RESULTS: From 2010 to 2015, 31 pts were enrolled (CHT: 17 pts; RT: 14pts). Four pts were excluded from the analysis. RPA VI (p = 0.048) and absence of MGMT methylation (p = 0.001) worsened OS significantly. Biopsy (p = 0.048), RPA class VI (p = 0.04) and chemotherapy (p = 0.007) worsened PFS. In the two arms the initial NSS scores were overlapping (CHT: 12.23 and RT: 12.30) and progressively decreased in both group and became significantly worse after 5 months in CHT arm (p = 0.05). Median QaS was 104 days and was significantly better in RT arm (p = 0.01). CONCLUSIONS: The data obtained are limited by the poor accrual. Both treatments were well tolerated. Patients in RT arm have a better PFS and QaS, without significant differences in OS. The deterioration of the NSS score would seem an important parameter and coincide with disease progression rather than with the toxicity of the treatment.

Metastasis-directed stereotactic radiotherapy for oligoprogressive castration-resistant prostate cancer: a multicenter study.

PURPOSE: Herein, we report the clinical outcomes of a multicenter study evaluating the role of SBRT in a cohort of patients affected by oligoprogressive castration-resistant prostate cancer (CRPC). MATERIALS AND METHODS: This is a retrospective multicenter observational study including eleven centers. Inclusion criteria of the current study were: (a) Karnofsky performance status > 80, (b) histologically proven diagnosis of PC, (c) 1-5 oligoprogressive metastases, defined as progressive disease at bone or nodes levels (detected by means of choline PET/CT or CT plus bone scan) during ADT, (d) serum testosterone level under 50 ng/ml during ADT, (e) controlled primary tumor, (f) patients treated with SBRT with a dose of at least 5 Gy per fraction to a biologically effective dose (BED) of at least 80 Gy using an alpha-to-beta ratio of 3 Gy, (g) at least 6 months of follow-up post-SBRT. RESULTS: Eighty-six patients for a total of 117 lesions were treated with SBRT. The median follow-up was 30.7 months (range 4-91 months). The median new metastasis-free survival after SBRT was 12.3 months (95% CI 5.5-19.1 months). One- and two-year distant progression-free survival was 52.3% and 33.7%, respectively. Twenty-six out of 86 patients underwent a second course of SBRT due to further oligoprogressive disease: This resulted in a median systemic treatment-free survival of 21.8 months (95% CI 17.8-25.8 months). One-year systemic treatment-free survival was 72.1%. CONCLUSION: SBRT appears to be a promising approach in oligoprogressive castration-resistant prostate cancer. Further investigations are warranted.

Hypofractionated radiation therapy in the management of locally advanced NSCLC: a narrative review of the literature on behalf of the Italian Association of Radiation Oncology (AIRO)-Lung Working Group.

A systematic literature was performed to assess the benefit in terms of effectiveness and feasibility of hypofractionated radiotherapy (HypoRT), with or without chemotherapy (CT), in the treatment of locally advanced non-small cell lung cancer (NSCLC). We have identified all studies, published from 2007 onwards, on patients with locally advanced NSCLC treated with HypoRT with radical intent, with a minimal dose per fraction of 2.4 Gy, with or without concurrent chemotherapy. Twenty-nine studies were identified, for a total of 2614 patients. Patients were divided in the concurrent chemo-radiation therapy group (CT-RT) and radiotherapy alone (RT). In RT group, the delivered dose ranged from 45 to 85.5 Gy, with a dose/fraction from 2.4 to 4 Gy. Actuarial 2-year PFS ranged from 13 to 57.8%, and 1, 2- and 3-year overall survival (OS) ranged from 51.3 to 95%, from 22 to 68.7%, and from 7 to 32%, respectively. Acute Grade ≥ 3 esophagitis occurred in 0-15%, while late esophageal toxicity was 0-16%. Acute pneumonitis occured in 0-44%, whereas late pneumonitis occured in 0-47%, most commonly grade ≤ G3. In CT-RT group, the delivered dose ranged from 52.5 to 75 Gy, with a dose/fraction ranging from 2.4 to 3.5 Gy. Actuarial 2-year PFS ranged from 19 to 57.8%, and OS at 1, 2 and 3 years ranged from 28 to 95%, 38.6 to 68.7%, and 31 to 44%, respectively. Acute Grade 2 and 3 esophagitis occurred in 3-41.7%, while late esophageal toxicity occurred in 0-8.3%. Acute pneumonitis ranged from 0 to 23%, whereas late pneumonitis occured 0-47%. HypoRT seems to be safe in patients with locally advanced NSCLC. The encouraging survival results of several studies analyzed suggest that hypofractionated radiation schemes should be further investigated in the future.

Concomitant radiotherapy and TKI in metastatic EGFR- or ALK-mutated non-small cell lung cancer: a multicentric analysis on behalf of AIRO lung cancer study group.

PURPOSE: To investigate the role of radiotherapy (RT) in the management of EGFR- or ALK-mutated metastatic non-small cell lung cancer (NSCLC) treated with TKI. MATERIALS AND METHODS: Clinical data of 106 patients (pts) from five Institutions treated with RT concomitant to TKI were retrospectively revised. Overall survival (OS) and toxicities were analyzed as endpoints of the study. RESULTS: Median age of pts was 65 years. TKIs were given for EGFR (81%)- or ALK (19%)-mutated metastatic NSCLC. Stereotactic RT (SRT) was delivered to 49 pts (46%). Patients with four or less metastasis were defined as oligometastatic/oligoprogressive (OM/OP); sites of RT were brain, bone, lung or others in 46%, 27%, 14% and 13%, respectively. Median OS was 23 months. At univariate analysis SRT, ECOG PS 0-1, OM/OP disease, lung sites and a TKI duration longer than median favorably affected OS (all p < 0.001). Multivariate analysis confirmed SRT (HR 0.355, CI 95% 0.212-0.595; p < 0.001) and median duration of TKI > 14 months (HR 0.17, 95% CI 0.10-0.30; p < 0.001) as independent factors related to better OS. Toxicities were rare. CONCLUSIONS: SRT seems to positively affect OS with limited toxicity in selected patients.

Radiation therapy in small cell lung cancer: a national Italian survey.

INTRODUCTION: Radiation therapy plays an important role in the management of SCLC both in curative and palliative setting, however, conflicting data from clinical trials incite debate over the appropriate use of radiation therapy regarding prophylactic cranial irradiation (PCI) and/or thoracic consolidative in extensive-stage SCLC (ES-SCLC). This survey is conducted to evaluate the current pattern of care among Italian radiation oncologists. METHODS: In June 2016, all Italian radiation oncologists were invited to a web-based survey. The survey contained 34 questions regarding the role of RT in SCLC. Questions pertaining the role of RT in the clinical management of both limited-stage (LS) and ES-SCLC were included. RESULTS: We received 48 responses from Italian radiation oncologists. More than half of respondents had been practicing for more than 10 years after completing residency training and 55% are subspecialists in lung cancer. Preferred management of LS-SCLC favored primary concurrent chemoradiotherapy (89%), even if the 36.9% usually delivered RT during or after the cycle 3 of chemotherapy, due to organizational issues. The most common dose and fractionation schedule in this setting was 60 Gy in 30 once-daily fractions. Furthermore, almost all respondents recommended PCI in patients with LS-SCLC. For ES-SCLC scenario, chemotherapy was defined the standard treatment by all respondents. PCI was recommended in ES-SCLC patients with thoracic complete remission (63% of respondents), with thoracic partial response (45%) and with thoracic stable disease (17%) after first-line chemotherapy. Lastly, the thoracic consolidative RT was recommended by 51% of respondents in patients with ES-SCLC in good response after first-line chemotherapy and a great variability was shown in clinical target volume definition, doses and fractionation schedules. CONCLUSIONS: Our analysis showed a high adherence to current guidelines among the respondents in regard to chemoradiation approach in LS-SCLC patients and to PCI indications and doses. The great variability in radiation therapy doses and volumes in the thoracic consolidative radiotherapy in ES-SCLC is concerning. Future clinical trials are needed to standardize these treatment approaches to improve treatment outcomes among patients with ES-SCLC.

Efficacy of stereotactic body radiotherapy in oligorecurrent and in oligoprogressive prostate cancer: new evidence from a multicentric study.

BACKGROUND: The aim of the present study is to evaluate the impact of metastases-directed stereotactic body radiotherapy in two groups of oligometastatic prostate cancer (PC) patients: oligorecurrent PC and oligoprogressive castration-resistant PC (oligo-CRPC). METHODS: Inclusion criteria of the present multicentre retrospective analysis were: (1) oligorecurrent PC, defined as the presence of 1-3 lesions (bone or nodes) detected with choline positron emission tomography or CT plus bone scan following biochemical recurrence; (2) oligo-CRPC, defined as metastases (bone or nodes) detected after a prostatic-specific antigen rise during androgen deprivation therapy (ADT). Primary end points were: distant progression-free survival (DPFS) and ADT-free survival in oligorecurrent PC patients; DPFS and second-line systemic treatment-free survival in oligo-CRPC patients. RESULTS: About 100 patients with oligorecurrent PC (139 lesions) and 41 with oligo-CRPC (70 lesions), treated between March 2010 and April 2016, were analysed. After a median follow-up of 20.4 months, in the oligorecurrent group 1- and 2-year DPFS were 64.4 and 43%. The rate of LC was 92.8% at 2 years. At a median follow-up of 23.4 months, in the oligo-CRPC group 1- and 2-year DPFS were 43.2 and 21.6%. Limitations include the retrospective design. CONCLUSIONS: Stereotactic body radiotherapy seems to be a useful treatment both for oligorecurrent and oligo-CRPC.

Redetermination of PD-L1 expression after chemio-radiation in locally advanced PDL1 negative NSCLC patients: retrospective multicentric analysis.

Background: Chemoradiation therapy (CRT) is the treatment of choice for locally advanced non-small cell lung cancer (LA-NSCLC). Several clinical trials that combine programmed cell death 1 (PD1) axis inhibitors with radiotherapy are in development for patients with LA-NSCLC. However, the effect of CRT on tumor cells programmed cell death ligand-1 (PD-L1) expression is unknown. Methods: In this multicentric retrospective study, we analyzed paired NSCLC specimens that had been obtained pre- and post-CRT. PD-L1 expression on tumor cells was studied by immunohistochemistry. The purpose of this study was to evaluate the feasibility, risk of complications, and clinical relevance of performing re-biopsy after CRT in patients with PD-L1 negative LA-NSCLC. Results: Overall, 31 patients from 6 centers with PD-L1 negative LA-NSCLC were analyzed. The percentage of tumor cells with PD-L1 expression significantly increased between pre- and post-CRT specimens in 14 patients (45%). Nine patients had unchanged PD-L1 expression after CRT, in five patients the rebiopsy material was insufficient for PD-L1 analysis and in two patients no tumor cells at rebiopsy were found. The post-rebiopsy complication rate was very low (6%). All patients with positive PD-L1 re-biopsy received Durvalumab maintenance after CRT, except one patient who had a long hospitalization for tuberculosis reactivation. Median PFS of patients with unchanged or increased PD-L1 expression was 10 and 16.9 months, respectively. Conclusion: CRT administration can induce PD-L1 expression in a considerable fraction of PD-L1 negative patients at baseline, allowing them receiving the maintenance Durvalumab in Europe. Hence, after a definitive CRT, PD-L1 redetermination should be considered in patients with LA-NSCLC PD-L1 negative, to have a better selection of maintenance Durvalumab candidates.

Sterotactic Ablative Radiotherapy in a Multicentric Series of Oligometastatic SCLC: The SAMOS Cohort.

AIMS: SCLC is the most aggressive lung cancer histology with a 5-year OS <10%. At the diagnosis, almost two-thirds of the SCLC an Extended Disease presentation. Two randomized studies (CASPIAN and ImPower133) demonstrated an OS improvement, when immunotherapy was prescribed as maintenance therapy after standard chemotherapy. To date, SABR has had a limited indication in managing metastatic SCLC, although recent reports proposed it as a valid treatment option in selected patients. We propose a retrospective multicentric analysis of patients treated with SABR for oligometastatic SCLC. METHOD: Data of patients affected by oligometastatic-SCLC treated with SABR between 2017 and 2022 in 11 Italian centers were collected. Clinical and therapeutic variables together with OS and time to next treatment were analyzed. Univariate analysis with Kaplan-Meier curve were calculated, and log-rank test were applied. Cox proportional hazard model was used for multivariate analysis. RESULTS: Data from 93 patients and 132 metastatic lesions were analyzed. The median age was 64 years (36-86) and all but 1 had Performance Status 0 or 1. Fifty-two patients presented ED at diagnosis. The first line treatment was radiochemotherapy in 42%, CHT alone in 24% and CHT-IO in 28%, others treatment accounts for 4% and only 2% of patients underwent best supportive care. Of the 132 lesions treated with SBRT 55 were in brain, 27 in lung, 11 in liver, 10 in lymph nodes, 8 in bones and 20 in adrenal gland. Median OS was 14 months, 1 year-OS and 2 years OS were 53% and 27%, respectively. The median TtNT was 14 months for the entire population. Of all the analyzed variables only, the anatomical site of the metastases and their number showed statistical significance in the univariate analysist, confirmed in the subsequent multivariate. CONCLUSION: SABR seems to play a role in delaying further systemic lines in oligometastatic disease and to extend the use of ongoing treatment in oligoprogressive state. Prospective studies are needed to confirm these findings.

Lattice Radiation Therapy in clinical practice: A systematic review.

Purpose: Lattice radiation therapy (LRT) is an innovative type of spatially fractionated radiation therapy. It aims to increase large tumors control probability by administering ablative doses without an increased toxicity. Considering the rising number of positive clinical experiences, the objective of this work is to evaluate LRT safety and efficacy. Method: Reports about LRT clinical experience were identified with a systematic review conducted on four different databases (namely, Medline, Embase, Scopus, and Cochrane Library) through the August 2022. Only LRT clinical reports published in English and with the access to the full manuscript text were considered as eligible. The 2020 update version PRISMA statement was followed. Results: Data extraction was performed from 12 eligible records encompassing 7 case reports, 1 case series, and 4 clinical studies. 81 patients (84 lesions) with a large lesion ranging from 63.2 cc to 3713.5 cc were subjected to exclusive, hybrid, and metabolism guided LRT. Excluding two very severe toxicity with a questionable relation with LRT, available clinical experience seem to confirm LRT safety. When a complete response was not achieved 3-6 months after LRT, a median lesion reduction approximately ≥50 % was registered. Conclusion: This systematic review appear to suggest LRT safety, especially for exclusive LRT. The very low level of evidence and the studies heterogeneity preclude drawing definitive conclusions on LRT efficacy, even though an interesting trend in terms of lesions reduction has been described.

Validation of RayStation Monte Carlo dose calculation algorithm for multiple LINACs.

PURPOSE: A photon Monte Carlo (MC) model was commissioned for flattened (FF) and flattening filter free (FFF) 6 MV beam energy. The accuracy of this model, as a single model to be used for three beam matched LINACs, was evaluated. METHODS: Multiple models were created in RayStation v.10A for three linacs equipped with Elekta "Agility" collimator. A clinically commissioned collapsed cone (CC) algorithm (GoldCC), a MC model automatically created from the CC algorithm without further optimization (CCtoMC) and an optimized MC model (GoldMC) were compared with measurements. The validation of the model was performed by following the recommendations of IAEA TRS 430 and comprised of basic validation in a water tank, validation in a heterogeneous phantom and validation of complex IMRT/VMAT paradigms using gamma analysis of calculated and measured dose maps in a 2D-Array. RESULTS: Dose calculation with the GoldMC model resulted in a confidence level of 3% for point measurements in water tank and heterogeneous phantom for measurements performed in all three linacs. The same confidence level resulted for GoldCC model. Dose maps presented an agreement for all models on par to each other with γ criteria 2%/2mm. CONCLUSIONS: The GoldMC model showed a good agreement with measured data and is determined to be accurate for clinical use for all three linacs in this study.