Tools to Guide Radiation Oncologists in the Management of DCIS.

Similar to invasive breast cancer, ductal carcinoma in situ is also going through a phase of changes not only from a technical but also a conceptual standpoint. From prescribing radiotherapy to everyone to personalized approaches, including radiotherapy omission, there is still a lack of a comprehensive framework to guide radiation oncologists in decision making. Many pieces of the puzzle are finding their place as high-quality data mature and are disseminated, but very often, the interpretation of risk factors and the perception of risk remain very highly subjective. Sharing the therapeutic choice with patients requires effective communication for an understanding of risks and benefits, facilitating an informed decision that does not increase anxiety and concerns about prognosis. The purpose of this narrative review is to summarize the current state of knowledge to highlight the tools available to radiation oncologists for managing DCIS, with an outlook on future developments.

Multi-omics integrative modelling for stereotactic body radiotherapy in early-stage non-small cell lung cancer: clinical trial protocol of the MONDRIAN study.

BACKGROUND: Currently, main treatment strategies for early-stage non-small cell lung cancer (ES-NSCLC) disease are surgery or stereotactic body radiation therapy (SBRT), with successful local control rates for both approaches. However, regional and distant failure remain critical in SBRT, and it is paramount to identify predictive factors of response to identify high-risk patients who may benefit from more aggressive approaches. The main endpoint of the MONDRIAN trial is to identify multi-omic biomarkers of SBRT response integrating information from the individual fields of radiomics, genomics and proteomics. METHODS: MONDRIAN is a prospective observational explorative cohort clinical study, with a data-driven, bottom-up approach. It is expected to enroll 100 ES-NSCLC SBRT candidates treated at an Italian tertiary cancer center with well-recognized expertise in SBRT and thoracic surgery. To identify predictors specific to SBRT, MONDRIAN will include data from 200 patients treated with surgery, in a 1:2 ratio, with comparable clinical characteristics. The project will have an overall expected duration of 60 months, and will be structured into five main tasks: (i) Clinical Study; (ii) Imaging/ Radiomic Study, (iii) Gene Expression Study, (iv) Proteomic Study, (v) Integrative Model Building. DISCUSSION: Thanks to its multi-disciplinary nature, MONDRIAN is expected to provide the opportunity to characterize ES-NSCLC from a multi-omic perspective, with a Radiation Oncology-oriented focus. Other than contributing to a mechanistic understanding of the disease, the study will assist the identification of high-risk patients in a largely unexplored clinical setting. Ultimately, this would orient further clinical research efforts on the combination of SBRT and systemic treatments, such as immunotherapy, with the perspective of improving oncological outcomes in this subset of patients. TRIAL REGISTRATION: The study was prospectively registered at clinicaltrials.gov (NCT05974475).

Impact of inter-observer variability on first axillary level dosimetry in breast cancer radiotherapy: An AIRO multi-institutional study.

This study quantified the incidental dose to the first axillary level (L1) in locoregional treatment plan for breast cancer. Eighteen radiotherapy centres contoured L1-L4 on three different patients (P1,2,3), created the L2-L4 planning target volume (single centre planning target volume, SC-PTV) and elaborated a locoregional treatment plan. The L2-L4 gold standard clinical target volume (CTV) along with the gold standard L1 contour (GS-L1) were created by an expert consensus. The SC-PTV was then replaced by the GS-PTV and the incidental dose to GS-L1 was measured. Dosimetric data were analysed with Kruskal-Wallis test. Plans were intensity modulated radiotherapy (IMRT)-based. P3 with 90° arm setup had statistically significant higher L1 dose across the board than P1 and P2, with the mean dose (Dmean) reaching clinical significance. Dmean of P1 and P2 was consistent with the literature (77.4% and 74.7%, respectively). The incidental dose depended mostly on L1 proportion included in the breast fields, underlining the importance of the setup, even in case of IMRT.

A narrative review for radiation oncologists to implement preoperative partial breast irradiation.

The strategy to anticipate radiotherapy (RT) before surgery, for breast cancer (BC) treatment, has recently generated a renewed interest. Historically, preoperative RT has remained confined either to highly selected patients, in the context of personalized therapy, or to clinical research protocols. Nevertheless, in the recent years, thanks to technological advances and increased tumor biology understanding, RT has undergone great changes that have also impacted the preoperative settings, embracing the modern approach to breast cancer. In particular, the reappraisal of preoperative RT can be viewed within the broader view of personalized and tailored medicine. In fact, preoperative accelerated partial breast irradiation (APBI) allows a more precise target delineation, with less variability in contouring among radiation oncologists, and a smaller treatment volume, possibly leading to lower toxicity and to dose escalation programs. The aim of the present review, which represents a benchmark study for the AIRC IG-23118, is to report available data on different technical aspects of preoperative RT including dosimetric studies, patient's selection and set-up, constraints, target delineation and clinical results. These data, along with the ones that will become available from ongoing studies, may inform the design of the future trials and representing a step toward a tailored APBI approach with the potential to challenge the current treatment paradigm in early-stage BC.Trial registration: The study is registered at clinicaltrials.gov (NCT04679454).

Intensity-modulated radiotherapy and cisplatin-based chemotherapy for anal cancer: long-term outcomes at a single institution.

PURPOSE: To evaluate oncological outcomes and late toxicities in a retrospective series of patients with locally-extended anal squamous cell carcinoma (ASCC), treated with curative Intensity Modulated Radiotherapy (IMRT) and chemotherapy. METHODS: ASCC patients who underwent chemo-radiotherapy with IMRT from 2010 to 2020 were included. Oncological outcomes were assessed in terms of overall survival (OS), disease-free survival (DFS), colostomy-free survival (CFS) and event-free survival (EFS). Late toxicity was detected according to CTCAE v.5.0 and RTOG late radiation morbidity scoring system. RESULTS: Ninety-five patients were included. Most patients (83%) received chemotherapy with oral Fluoropyrimidine plus Cisplatin. The median follow-up was 5.5 years. The OS was 85.2%, 82.1% and 79.3% at 3, 5 and 8 years, respectively. The DFS was 73.1%, 70%, and 65.3% at 3, 5 and 8 years, respectively; 3, 5 and 8 years CFS was 86.2%, 84.3% and 84.3%, respectively. The EFS was 71%, 67.9% and 63.1%, at 3, 5 and 8 years, respectively. On univariable analysis, a statistically significant lower OS was found for patients with T3-T4 stage (HR = 4.58, p = 0.005) and overall treatment time (OTT) ≥ 47 days (HR = 3.37, p = 0.038). A statistically significant lower DFS was reported for patients with T3-T4 stage (HR = 2.72, p = 0.008) and Serum Squamous Cell Carcinoma Antigen (SCC) value post-RT > 1.5 (HR = 2.90, p = 0.038.). Ten severe late toxicity (≥ G3) events were reported in 8 patients (8.6%). CONCLUSIONS: Our data confirm IMRT concomitant with a Cisplatin-based chemotherapy as an effective treatment of ASCC, ensuring acceptable long-term toxicities and good oncological outcomes.

The T-N tract involvement as a new prognostic factor for PORT in locally advanced oral cavity tumors.

OBJECTIVE: The space comprised between tumor and neck lymph nodes (T-N tract) is one of the main routes of tumor spread in oral cavity tumors. Aim of the study was to investigate the impact of T-N tract involvement on the postoperative radiotherapy (PORT) outcomes. MATERIALS AND METHODS: Patients (pts) treated between 2000 and 2016 with indication to PORT were retrospectively retrieved. Inclusion criteria were: (a) locally advanced tumors of the oral cavity, (b) who received with indication to PORT (c) with a minimum follow-up of six months. RESULTS: One hundred and fifty-seven pts met the inclusion criteria (136 pts treated with PORT and 21 pts not treated with PORT). In the PORT cohort, the T-N tract involvement had no impact on both OS (p = .09) and LRFS (p = .2). Among the non-PORT cohort, both OS (p = .007) and LRFS (p = .017) were worse for pts with positive T-N tract compared to those with negative T-N tract. PORT improved both OS (p = .008) and LRFS (p = .003) in pts with positive T-N tract but not in those with negative T-N tract (p = .36 and p = .37, respectively). CONCLUSIONS: Our results suggest that involvement of T-N tract should be considered as prognostic factors informing the indication to PORT.

Ten-year results of hypofractionated whole breast radiotherapy and intraoperative electron boost in premenopausal women.

AIM: To evaluate outcome of intraoperative electron boost (IOERT) and hypofractionated whole breast irradiation (HWBI) for breast cancer (BC) in young women. METHODS AND MATERIALS: Women aged ≤ 48 with pT1-2 N0-1 BC received 12 Gy IOERT boost during conservative surgery followed by 3-dimensional conformal HWBI in 13 fractions (2.85 Gy/die). Local relapses (LR) and survival (disease-free, DFS; specific, BCSS; overall, OS) were analyzed. RESULTS: 481 consecutive BC patients, mostly node negative, with median age of 42 were treated between 2004 and 2014. Median tumor size was 1.48 cm and median IOERT collimator was 4 cm. After 25-day mean interval, HWBI was delivered. At a median follow-up of 9.6 years, there were 23 LRs (4.8 %, 9 of which were in the boost region). Ten-year LR cumulative incidence was 4.1 % (95 %CI, 2.5-6.3). Over time, local control rate decreased for Luminal A and HER2 positive with negative hormonal receptors, while remained steady for triple negative. At multivariate analysis, LR predictors included age < 40, extensive intraductal component and the use of 4-cm IOERT collimator size. Ten-year survival outcomes were as follows: DFS 80.0 % (95 % CI, 75.8-83.5), BCSS 97.5 % (95 % CI, 95.5-98.6 %), OS 96.5 % (95 % CI, 94.3-97.9). Luminal B HER2 negative had the worse survival outcomes. Perioperative complications were uncommon (16.4 %), acute toxicity was mild (<2% Grade 3), but moderate/severe fibrosis was described in 40.8 % of the cases. Cosmesis was scored as excellent/good in 86 % of the cases. CONCLUSIONS: ELIOT boost and HWBI achieved an excellent local control at the cost of tumor bed fibrosis. IOERT boost dose lower than 12 Gy is advisable.

Single fraction ablative preoperative radiation treatment for early-stage breast cancer: the CRYSTAL study - a phase I/II clinical trial protocol.

BACKGROUND: Breast-conserving surgery (BCS) and whole breast radiation therapy (WBRT) are the standard of care for early-stage breast cancer (BC). Based on the observation that most local recurrences occurred near the tumor bed, accelerated partial breast irradiation (APBI), consisting of a higher dose per fraction to the tumor bed over a reduced treatment time, has been gaining ground as an attractive alternative in selected patients with low-risk BC. Although more widely delivered in postoperative setting, preoperative APBI has also been investigated in a limited, though increasing, and number of studies. The aim of this study is to test the feasibility, safety and efficacy of preoperative radiotherapy (RT) in a single fraction for selected BC patients. METHODS: This is a phase I/II, single-arm and open-label single-center clinical trial using CyberKnife. The clinical investigation is supported by a preplanning section which addresses technical and dosimetric issues. The primary endpoint for the phase I study, covering the 1st and 2nd year of the research project, is the identification of the maximum tolerated dose (MTD) which meets a specific target toxicity level (no grade 3-4 toxicity). The primary endpoint for the phase II study (3rd to 5th year) is the evaluation of treatment efficacy measured in terms of pathological complete response rate. DISCUSSION: The study will investigate the response of BC to the preoperative APBI from different perspectives. While preoperative APBI represents a form of anticipated boost, followed by WBRT, different are the implications for the scientific community. The study may help to identify good responders for whom surgery could be omitted. It is especially appealing for patients unfit for surgery due to advanced age or severe co-morbidities, in addition to or instead of systemic therapies, to ensure long-term local control. Moreover, patients with oligometastatic disease synchronous with primary BC may benefit from APBI on the intact tumor in terms of tumor progression free survival. The study of response to RT can provide useful information about BC radiobiology, immunologic reactions, genomic expression, and radiomics features, to be tested on a larger scale. TRIAL REGISTRATION: The study was prospectively registered at clinicaltrials.gov ( NCT04679454 ).

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.

Hypofractionated proton therapy in breast cancer: where are we? A critical review of the literature.

PURPOSE: To critically review available literature on hypofractionated (≥ 3 Gy/fraction) proton therapy (PT) for breast cancer (BCa). METHODS: A systematic screening of the literature was performed in April 2021 in compliance with the preferred reporting items for systematic reviews and meta-analyses recommendations. All full-text publication written in English were considered eligible. Acute and late toxicities, oncological outcomes and dosimetric features were considered for the analysis. RESULTS: Twelve publications met the inclusion criteria; all studies but one focused on accelerated partial breast irradiation (APBI). Eleven works considered post-operative patients, one referred to ABPI as a curative-intent modality. The dosimetric profile of PT compared favorably with both photon-based 3D conformal and intensity-modulated techniques, while a more extended follow-up is warranted to fully assess both the long-term toxicities and the non-inferiority of oncological outcomes. CONCLUSION: Our work shows that results on PT for BCa are currently only available for APBI applications, with dosimetric analyses demonstrating a clear advantage over both 3D conformal and intensity modulated X-rays techniques, especially when ≥ 2 treatment fields were used. However, further evidence is needed to define whether such theoretical benefit translates into clinical improvements, especially in the long-term.

Ultra-hypofractionated whole breast adjuvant radiotherapy in the real-world setting: single experience with 271 elderly/frail patients treated with 3D and IMRT technique.

PURPOSE: The purpose of the study was to evaluate the toxicity, local control, overall and disease-free survival of elderly breast cancer (BC) patients treated with adjuvant once-weekly ultra-hypofractionated radiotherapy (RT) either with intensity-modulated RT (IMRT) or 3D conformal RT (3DCRT). METHODS: From July 2011 to July 2018, BC patients receiving 5.7 Gy once a week for 5 weeks to the whole breast after breast-conserving surgery were considered for the study. Inclusion criteria were: T1-T3 invasive BC, no or limited axillary involvement, age ≥ 65 years or women with commuting difficulties or disabling diseases. RESULTS: A total of 271 patients were included in the study. Median age was 76 (46-86) years. Most of BC were T1 (77%), while the remaining were T2 (22.2%) and T3 (0.4%). Axillary status was negative in 68.3% of the patients. The only severe acute toxicity (G3) at the end of RT was erythema (0.4%), registered in the 3DCRT group; no G3 edema or epitheliolysis was recorded. With 18 months of median follow-up, severe early-late toxicity (G3) was reported in terms of fibrosis and breast retraction, both with an incidence of 1.4%, mostly in the 3DCRT group. Oncological outcomes at a median follow-up of 2.9 years reported 249/271 (91.9%) patients alive and free from any event and 5 (1.8%) isolated locoregional recurrences. At 3 years, disease-free survival and overall survival were 94.9% and 97.8%, respectively. Breast volume > 500 cm3 was reported as predictive for moderate-severe (≥ G2) acute toxicity. CONCLUSIONS: Weekly ultra-hypofractionated whole breast RT seems feasible and effective. Toxicity was mild, local control was acceptable, and overall survival was 97.8% at 3 years. Rates of severe toxicity were reduced with the IMRT technique.

The POLO (Partially Omitted Lobe) approach to safely treat in-breast recurrence after intraoperative radiotherapy with electrons.

OBJECTIVES: The aim of this study is to evaluate feasibility of salvage 4-week hypofractionated whole breast radiotherapy (WBRT) in patients with in-breast recurrence after receiving intraoperative radiotherapy with electrons (IOERT) for primary breast cancer (BC). METHODS: BC patients who had repeated quadrantectomy underwent modified WBRT with intensity-modulated radiotherapy using Helical Tomotherapy to underdose the IOERT region. This approach, called POLO (Partially Omitted Lobe), excluded the IOERT volume from receiving the full prescription dose. RESULTS: Nine patients were treated with this approach, receiving 45 Gy in 20 fractions. A simultaneous integrated boost of 2.5 Gy in 20 fractions was delivered in 6/9 patients. Dose constraints and planning objectives were reported. No severe toxicity was reported while local control and overall survival were 100%. CONCLUSION: The POLO approach is technically feasible and capable to achieve a significant reduction of radiation dose delivered to the previous treated IOERT area. ADVANCES IN KNOWLEDGE: The study demonstrates the technical and dosimetric feasibility of conservative salvage whole breast radiotherapy, while sparing the area already treated with IORT, in patients with in-breast recurrence.

Comparing TomoHelical and TomoDirect in postmastectomy hypofractionated radiotherapy after immediate breast reconstruction.

BACKGROUND: Postmastectomy radiotherapy (PMRT) with TomoHelical™ (TH) or TomoDirect™ (TD) allows a uniform target coverage. In this study, we compare treatment plans using TD and TH in the setting of hypofractionated PMRT and immediate breast reconstruction. MATERIAL AND METHODS: The TD-treatment plans of breast cancer patients treated between May 2016 and August 2019 were retrospectively selected. All the TD plans were re-planned on TH with the same prescription dose (40.05 Gy/15 fractions) and according to our dose/volume constraints. Data about the 2 treatment plans were compared with a focus on PTV coverage and all the organs at risk (OARs) constraints. RESULTS: Fifty patients for a total number of 100 treatment plans (50 with TD and 50 re-planned with TH) were analyzed. All the median value in the TD PTV CHEST WALL plans fulfilled the predefined planning objectives, even though TH emerged as best for target coverage with statistically significant difference for V90%. TD provided the lowest V95% for the PTV SVC, but the median value was near to the recommended value of 90% (89.8 % vs 98.6% for TD and TH, respectively). Overall, TD reached the best OARs sparing. The main statistically significant differences with TH were for contralateral breast, ipsilateral and contralateral lung. All the other dose values for TH were higher than TD, but they fulfilled the recommended/acceptable predefined planning objectives. CONCLUSIONS: In the setting of PMRT, TD compared to TH reached an acceptable target volume coverage, with an optimal sparing of OARs.

Predictors of positive axillary non-sentinel lymph nodes in breast cancer patients with positive sentinel lymph node biopsy after neoadjuvant systemic therapy.

AIM: To assess the rate of positive non-sentinel lymph nodes (non-SLNs) after neoadjuvant systemic therapy (NAST) in breast cancer (BC) following positive sentinel lymph node biopsy (SLNB). MATERIALS AND METHODS: From institutional database, 265 consecutive patients receiving NAST for cT1-3, any N, M0 BC between 2001 and 2018 were identified. Patients presented clinically negative axilla before surgery and were candidate for SLNB. Following metastatic SLNB, completion axillary lymph node dissection (AxLND) was performed. Non-SLNs rate was investigated using multivariate (MV) logistic regression models. The distribution of non-SLNs across the axilla was observed. RESULTS: Positive non-SLNs were found in 62.3% of cases and showed no correlation with SLN metastasis size. At MV, statistically significant variables associated with non-SLNs were older age (p = 0.025), clinically positive lymph nodes (p = 0.002), SLN extracapsular extension (ECE, p = 0.001), and higher ratio of positive SLNs/total SLNs (p = 0.016). ECE and higher nodal ratio were independent predictors of III axillary level positivity. By categorizing patients in intermediate- and high-risk groups using the study variables, positive non-SLNs were found in the range of 23-56% across the three axillary levels, rates which did not support radiotherapy volume de-escalation. The III axillary level lower involvement (6.3%) was better identified with the RAPCHEM trial criteria based on the ypN status after AxLND. CONCLUSIONS: Involved non-SLNs rate following positive SLNB after NAST is nearly double the rate observed after primary surgery, supporting some intervention on the axilla. If AxLND is limited to I and II level, the involvement of the III level up to 31% of the cases seems to require some additional treatment, while the omission in selected cases needs further investigation.

Mastectomy alone for pT1-2 pN0-1 breast cancer patients: when postmastectomy radiotherapy is indicated.

PURPOSE: To assess outcome of breast cancer (BC) stages pT1-2 N0-1 after mastectomy alone and to identify prognostic factors calling for the need of postmastectomy radiotherapy. METHODS: Patients who were not eligible for breast conserving surgery (BCS) were operated on with mastectomy between 1998 and 2008. Locoregional (LRR), distant (DM) control and breast cancer specific survival (BCSS) were retrospectively evaluated. Cumulative incidence (CI) of events was estimated according to Kalbfleisch and Prentice while Gray's test tested difference. Kaplan-Meier method for survival and Cox proportional hazards model for univariable and multivariable analysis were used. A matched pair analysis between mastectomy alone and BCS plus whole breast irradiation (WBI), using the propensity score method, was performed. RESULTS: 1281 pT1-2 N0 and 1081 pT1-2 N1 were identified. Median follow-up was 8.2 years (9.2 years for survival). Overall, LRR rate was low for both N0 and N1 subgroups (10-year CI, 8.8% and 10.9%, respectively). Young age, lymphovascular invasion and Ki-67 ≥ 20% were proved to be statistically significant prognostic factors at multivariable analysis. The combination of ≥ 2 risk factors increased LRR rate to ≥ 15%. Risk factors combination weighed on LRR rate more than nodal status itself. DM rate doubled moving from negative to positive nodal status (10-year CI 10.5% versus 20.3%, respectively). BCSS remained high in both N0 and N1 subgroups (10-year CI 92.4% versus 84.5%, respectively). Remarkably, all the molecular subtypes except Luminal A significantly affected DM and BCSS both in the N0 and N1 subgroups. Nodes number significantly impacted on DM and BCSS but not on locoregional control. In the matched pair analysis, WBI decreased nodal recurrence rate and improved distant control, without affecting survival. CONCLUSIONS: Selected patients, namely those with at least two additional risk factors, presented high enough LRR risk to support the use of postmastectomy radiotherapy in both N0 and N1 subgroups. Moreover, the observation that radiotherapy may provide benefits that go beyond local control deserves to be further investigated.

Intensity-modulated radiotherapy (IMRT) in the treatment of squamous cell anal canal cancer: acute and early-late toxicity, outcome, and efficacy.

PURPOSE: To retrospectively review our experience on 84 patients with squamous cell anal canal cancer (SCAC) within 12 months after combined treatment with intensity-modulated RT (IMRT), in terms of acute and early-late toxicity, overall treatment time and interruptions, colostomy-free survival (CFS), and tumor response. METHODS: Acute gastrointestinal (GI), genitourinary (GU), and cutaneous (CU) toxicities were assessed according to Common Toxicity Criteria for Adverse Events (CTCAE) version 4.03. Early-late toxicity was scored using the Radiation Therapy Oncology Group (RTOG) late radiation morbidity scoring system. Tumor response was evaluated with response evaluation criteria in solid tumors (RECIST) v1.1. RESULTS: Acute toxicity for 84 subjects (100%): severe (≥ G3) GI and skin toxicity was observed in 4 (5%) and 19 patients (23%), respectively. Early-late toxicity for 73 subjects (87%): severe (≥ G3) GI and vulvo-vaginal toxicity was observed in 2 (3%) and 2 (3%) patients, respectively. No acute or early-late severe GU toxicity was reported. A treatment interruption occurred in 65 patients (77%). CFS was 96% (95% CI 89-99) at 6 months and 92% (95% CI 83-96) at 12 months. At 6 months complete response (CR), partial response (PR) and progressive disease (PD) was observed in 70 (83%), 3 (4%), and 7 patients (8%), respectively. At 12 months, CR was observed in 60 patients (81%); eleven patients (15%) experienced PD. CONCLUSION: Our study showed an excellent clinical result and very low acute toxicity rates, confirming the IMRT as standard of care for curative treatment of anal cancer patients. The current trial was registered with the number IEO N87/11.

Breast Adjuvant Radiotherapy Amid the COVID-19 Crisis in a Hub Cancer Center, Lombardy, Italy.

INTRODUCTION: During the COVID-19 pandemic, Lombardy (Northern Italy) Regional Health Council created hubs for cancer care, meant to be SARS-CoV-2-free pathways for cancer patients. The workflow of breast cancer (BC) radiotherapy (RT) in one of the hubs is presented here. METHODS: Candidates to adjuvant RT during the pandemic peak of March-April 2020 were compared to those treated in the same period of 2019, and patient volume, deferral rate, and type of RT were analyzed. Statistics were calculated with χ2 or Fisher exact tests for categorical variables, and the Wilcoxon rank test for continuous variables. RESULTS: In March-April 2020 the BC patient volume increased by 28% compared to the same period in 2019 (scheduled patients: 175 vs. 137) and amid travel restrictions it was kept high (treated patients: 136 vs. 133), mainly due to an influx from across Lombardy. RT schemes basically did not change, being already centered on hypofractionation. The increase of median time (67 vs. 74.5 days in 2019 and 2020, respectively) to the commencement of RT for low-risk patients was clinically negligible yet statistically significant (p = 0.03), and in line with the pertinent recommendations. No significant difference was found in the time interval between treatments and RT for high-risk patients. Concomitant chemoradiotherapy was avoided throughout the pandemic peak. Twenty-one women (13.6%) delayed either computed tomography simulation or RT commencement mainly because of COVID-19-related concerns and mobility restrictions. CONCLUSION: The workload for BC was high during the pandemic peak. Hubs allowed the continuation of oncologic treatments, while mitigating the strain on frontline COVID-19 hospitals.

Stereotactic radiotherapy for prostate bed recurrence after prostatectomy, a multicentric series.

OBJECTIVE: To assess the safety and effectiveness of stereotactic salvage radiotherapy (SSRT) in RT-naïve patients affected by macroscopic prostate bed recurrence. PATIENTS AND METHODS: Consecutive patients treated for prostate bed macroscopic recurrence in three different Italian institutes were reviewed. Patients were treated with SSRT, with a total dose of 30-40 Gy in five fractions, the mean pre-SSRT PSA level was 2.3 ng/mL. Two different PSA thresholds were defined and biochemical recurrence-free survival (BCRFS) was reported, in order to better express outcome: BCRFS1 (a PSA level increase of >10% compared to the pre-SSRT value) and BCRFS2 (a PSA level increase of >0.2 ng/mL for patients with a PSA nadir of <0.2 ng/mL or two consecutive PSA level increases of >25% compared to nadir in patients with a PSA nadir of <0.2 ng/mL). RESULTS: In all, 90 patients were treated, with a mean (range) follow-up of 21.2 (2-64) months, and 17 of these patients (19%) had concomitant androgen-deprivation therapy (ADT) during SSRT. Complete biochemical response, defined as a PSA nadir of <0.2 ng/mL, was obtained in 39 of the 90 patients (43.3%). Considering BCRFS1, 25 patients (27.8%) had BCR, with an actuarial median BCRFS1 time of 36.4 months. For BCRFS2, BCR was reported in 32 patients (35.5%), with an actuarial median BCRFS2 time of 24.3 months. There was no Grade >2 toxicity. CONCLUSIONS: SSRT was found to yield significant biochemical control and allowed ADT delay despite adverse features.

Stereotactic radiation therapy in oligometastatic colorectal cancer: outcome of 102 patients and 150 lesions.

To evaluate the local control (LC), progression free survival (PFS), out-field PFS, overall survival (OS), toxicity and failure predictors of SRT in a series of various sites oligometastatic CRC patients. Patients with oligometastatic CRC disease were analyzed retrospectively. The SRT prescribed dose was dependent on the lesion volume and its location. 102 consecutive oligometastatic CRC patients (150 lesions) were included. They underwent SRT between 2012 and 2015. Median prescription dose was 45 Gy (median dose/fraction was 15 Gy/3 fractions biological equivalent dose (BED10) 112.5 Gy). Median follow-up was 11.4 months. No patients experienced G3 and G4 toxicity. No progression was found in 82% (radiological response at 3 months) and 85% (best radiological response) out of 150 evaluable lesions. At 1 and 2 years: LC was 70% and 55%; OS was 90% and 90%; PFS was 37% and 27%; out-field PFS was 37% and 23% respectively. Progressive disease was correlated with BED10 (better LC when BED10 was ≥ 75 Gy (p < 0.0001)). In multivariate analysis, LC was higher in lesions with a Plpnning target volume (PTV) volume < 42 cm3 and BED10 ≥ 75 Gy. Patients with Karnofsky performance status < 90 showed higher out-field progression. SRT is an effective treatment for patients with oligometastases from CRC. Its low treatment-associated morbidity and acceptable LC make of SRT an option not only in selected cases. Further studies should be focused to clarify which patient subgroup will benefit most from this treatment modality and to define the optimal dose to improve LC while maintaining low toxicity profile.

Evaluation of target coverage and margins adequacy during CyberKnife Lung Optimized Treatment.

PURPOSE: Evaluation of target coverage and verification of safety margins, in motion management strategies implemented by Lung Optimized Treatment (LOT) module in CyberKnife system. METHODS: Three fiducial-less motion management strategies provided by LOT can be selected according to tumor visibility in the X ray images acquired during treatment. In 2-view modality the tumor is visible in both X ray images and full motion tracking is performed. In 1-view modality the tumor is visible in a single X ray image, therefore, motion tracking is combined with an internal target volume (ITV)-based margin expansion. In 0-view modality the lesion is not visible, consequently the treatment relies entirely on an ITV-based approach. Data from 30 patients treated in 2-view modality were selected providing information on the three-dimensional tumor motion in correspondence to each X ray image. Treatments in 1-view and 0-view modalities were simulated by processing log files and planning volumes. Planning target volume (PTV) margins were defined according to the tracking modality: end-exhale clinical target volume (CTV) + 3 mm in 2-view and ITV + 5 mm in 0-view. In the 1-view scenario, the ITV encompasses only tumor motion along the non-visible direction. Then, non-uniform ITV to PTV margins were applied: 3 mm and 5 mm in the visible and non-visible direction, respectively. We defined the coverage of each voxel of the CTV as the percentage of X ray images where such voxel was included in the PTV. In 2-view modality coverage was calculated as the intersection between the CTV centred on the imaged target position and the PTV centred on the predicted target position, as recorded in log files. In 1-view modality, coverage was calculated as the intersection between the CTV centred on the imaged target position and the PTV centred on the projected predictor data. In 0-view modality coverage was calculated as the intersection between the CTV centred on the imaged target position and the non-moving PTV. Similar to dose-volume histogram, CTV coverage-volume histograms (defined as CVH) were derived for each patient and treatment modality. The geometric coverages of the 90% and 95% of CTV volume (C90, C95, respectively) were evaluated. Patient-specific optimal margins (ensuring C95 ≥ 95%) were computed retrospectively. RESULTS: The median ± interquartile-rage of C90 and C95 for upper lobe lesions was 99.1 ± 0.6% and 99.0 ± 3.1%, whereas they were 98.9 ± 4.2% and 97.8 ± 7.5% for lower and middle lobe tumors. In 2-view, 1-view and 0-view modality, adopted margins ensured C95 ≥ 95% in 70%, 85% and 63% of cases and C95 ≥ 90% in 90%, 88% and 83% of cases, respectively. In 2-view, 1-view and 0-view a reduction in margins still ensured C95 ≥ 95% in 33%, 78% and 59% of cases, respectively. CONCLUSIONS: CTV coverage analysis provided an a-posteriori evaluation of the treatment geometric accuracy and allowed a quantitative verification of the adequacy of the PTV margins applied in CyberKnife LOT treatments offering guidance in the selection of CTV margins.