Spot-scanning proton therapy for early breast cancer in free breathing versus deep inspiration breath-hold.

BACKGROUND AND PURPOSE: Proton therapy for breast cancer is usually given in free breathing (FB). With the use of deep inspiration breath-hold (DIBH) technique, the location of the heart is displaced inferiorly, away from the internal mammary nodes and, thus, the dose to the heart can potentially be reduced. The aim of this study was to explore the potential benefit of proton therapy in DIBH compared to FB for highly selected patients to reduce exposure of the heart and other organs at risk. We aimed at creating proton plans with delivery times feasible with treatment in DIBH. MATERIAL AND METHODS: Sixteen patients with left-sided breast cancer receiving loco-regional proton therapy were included. The FB and DIBH plans were created for each patient using spot-scanning proton therapy with 2-3 fields, robust and single field optimization. For the DIBH plans, minimum monitor unit per spot and spot spacing were increased to reduce treatment delivery time. RESULTS: All plans complied with target coverage constraints. The median mean heart dose was statistically significant reduced from 1.1 to 0.6 Gy relative biological effectiveness (RBE) by applying DIBH. No statistical significant difference was seen for mean dose and V17Gy RBE to the ipsilateral lung. The median treatment delivery time for the DIBH plans was reduced by 27% compared to the FB plans without compromising the plan quality. INTERPRETATION: The median absolute reduction in dose to the heart was limited. Proton treatment in DIBH may only be relevant for a subset of these patients with the largest reduction in heart exposure.

Pelvic Insufficiency Fractures and Bone Pain after Radiation Therapy for Anal Cancer: Relation to Pelvic Bone Dose-Volume Parameters.

Purpose: Chemoradiation therapy is the primary treatment for anal cancer. Radiation therapy (RT) can weaken the pelvic bone structure, but the risk of pelvic insufficiency fractures (PIFs) and derived pain in anal cancer is not yet established. We determined the frequency of symptomatic PIFs after RT for anal cancer and related this to radiation dose to specific pelvic bone substructures. Methods and Materials: In a prospective setting, patients treated with RT for anal cancer had magnetic resonance imaging 1 year after RT. PIFs were mapped to 17 different bone sites, and we constructed a guideline for detailed delineation of pelvic bone substructures. Patients were interviewed regarding pain and scored according to Common Terminology Criteria for Adverse Effects. Dose-volume relationships for specific pelvic bone substructures and PIFs were determined for V20 to V40 Gy mean and maximum doses. Results: Twenty-seven patients were included, and 51.9% had PIFs primarily located in the alae of the sacral bone. Patients with PIFs had significantly more pelvic pain (86% vs 23%, P = .001) and 43% had grade 2 bone pain. Dose-volume parameters for sacral bone and sacral alae were significantly higher in patients with PIFs (P < .05). V30 Gy (%) for sacral bone and alae implied an area under the curve of 0.764 and 0.758, respectively, in receiver operating characteristic analyses. Conclusions: We observed a high risk of PIFs in patients treated with RT for anal cancer 1 year after treatment. A significant proportion had pain in the sites where PIFs were most frequently found. Radiation dose to pelvic bone substructures revealed relation to risk of PIFs and can be used for plan optimization in future clinical trials.

Management of treatment-related sequelae following colorectal cancer.

AIM: Colorectal cancer survivors are one of the most rapidly growing groups of patients living with and beyond cancer. In a national multidisciplinary setting, we have examined the extent of late treatment-related sequelae in colorectal cancer survivors and present the scientific evidence for management of these conditions in this patient category with the aim of facilitating identification and treatment. METHOD: A systematic search for existing guidelines and relevant studies was performed across 16 and 4 databases, respectively, from inception to 2021. This yielded 13 guidelines and 886 abstracts, of which 188 were included in the finalized guideline (231 included for full text review). Secondarily, bibliographies were cross-referenced and 53 additional articles were included. RESULTS: Symptoms have been divided into overall categories including psychosocial, bowel-related, urinary, sexual (male and female), pain/neuropathy and fatigue symptoms or complaints that are examined individually. Merging and grading of data resulted in 22 recommendations and 42 management strategies across categories. Recommendations are of a more general character, whereas management strategies provide more practical advice suited for initiation on site before referral to specialized units. CONCLUSION: Treatment-related sequelae in colorectal cancer survivors are common and attention needs to be focused on identifying patients with unmet treatment needs and the development of evidence-based treatment algorithms.

Spot-scanning proton therapy for targets with adjacent cardiac implantable electronic devices - Strategies for breast and head & neck cancer.

BACKGROUND AND PURPOSE: Cardiac implantable electronic device (CIED) malfunctions can be induced by secondary neutron dose from spot-scanning proton therapy. A recent in-vitro study investigating secondary neutron dose to CIEDs up to 7 mSv per fraction found that exposure of secondary neutrons in this range was clinically manageable. This study presents decision algorithms proposed by a national expert group for selection of patients with breast and head & neck (H&N) cancer with CIEDs adjacent to target for proton therapy based on the 7 mSv threshold. METHODS AND MATERIALS: Ten patients with breast cancer and five with H&N cancer were included in the study. Five patients with breast cancer received photon therapy with CIED and proton plans were retrospectively created. The remaining patients received proton therapy without CIED and a worst-case position of a virtual CIED was retrospectively delineated. Secondary neutron dose was estimated as ambient dose equivalent H*(10) using Monte Carlo simulations. RESULTS: For patients with breast cancer and with contralateral CIED, the secondary neutron dose to the CIED was below 7 mSv per fraction for CTV < 1500 cm3 in 2 Gy fractions and CTV < 1000 cm3 in 2.67 Gy fractions. The secondary neutron dose to the CIED was below 7 mSv per fraction for all patients with H&N cancer. CONCLUSIONS: Simulations of neutron exposure suggest that proton therapy is feasible for most patients with CIED adjacent to target. This forms the basis for decision algorithms for selection of patients with CIED for proton therapy.

Proton therapy for early breast cancer patients in the DBCG proton trial: planning, adaptation, and clinical experience from the first 43 patients.

BACKGROUND: The Danish Breast Cancer Group (DBCG) Proton Trial randomizes breast cancer patients selected on high mean heart dose (MHD) or high lung dose (V20Gy/V17Gy) in the photon plan between photon and proton therapy. This study presents the proton plans and adaptation strategy for the first 43 breast cancer patients treated with protons in Denmark. MATERIAL AND METHODS: Forty-four proton plans (one patient with bilateral cancer) were included; 2 local and 42 loco-regional including internal mammary nodes (IMN). Nineteen patients had a mastectomy and 25 a lumpectomy. The prescribed dose was either 50 Gy in 25 fractions (n = 30) or 40 Gy in 15 fractions (n = 14) wherefrom five received simultaneous integrated boost to the tumor bed. Using 2-3 en face proton fields, single-field optimization, robust optimization and a 5 cm range shifter ensured robustness towards breathing motion, setup- and range uncertainties. An anatomical evaluation was performed by evaluating the dose after adding/removing 3 mm and 5 mm tissue to/from the body-outline and used to define treatment tolerances for anatomical changes. RESULTS: The nominal and robust criteria were met for all patients except two. The median MHD was 1.5 Gy (0.5-3.4 Gy, 50 Gy) and 1.1 Gy (0.0-1.5 Gy, 40 Gy). The anatomical evaluations showed how 5 mm shrinkage approximately doubled the MHD while 5 mm swelling reduced target coverage of the IMN below constraints. Ensuring 3-5 mm robustness toward swelling was prioritized but not always achieved by robust optimization alone emphasizing the need for a distal margin. Twenty-eight patients received plan adaptation, eight patients received two, and one received five. CONCLUSION: This proton planning strategy ensured robust treatment plans within a pre-defined level of acceptable anatomical changes that fulfilled the planning criteria for most of the patients and ensured low MHD.

Risk of Cardiac Implantable Electronic Device Malfunctioning During Pencil Beam Proton Scanning in an In Vitro Setting.

PURPOSE: Cardiac implantable electronic devices (CIED) are sensitive to scattered secondary neutrons from proton beam irradiation. This experimental in vitro study investigated risk of CIED errors during pencil beam proton therapy. METHODS AND MATERIALS: We used 62 explanted CIEDs from 4 manufacturers; 49 CIEDs were subjected to a simulated clinical protocol with daily 2 Gy relative biological effectiveness fractions prescribed to the phantom. Devices were located at 3 different lateral distances from the spread-out Bragg peak to investigate the risk of permanent or temporary device errors. Additionally, 13 devices with leads connected were monitored live during consecutive irradiations to investigate the risk of noise, over- or undersense, pace inhibition, and inappropriate shock therapy. RESULTS: We detected 61 reset errors in 1728 fractions, and all except 1 CIED were reprogrammed to normal function. All, except 1 reset, occurred in devices from the same manufacturer. These were successfully reprogrammed to normal function. The 1 remaining CIED was locked in permanent safety mode. Secondary neutron dose, as estimated by Monte Carlo simulations, was found to significantly increase the odds of CIED resets by 55% per mSv. Clinically significant battery depletion was observed in 5 devices. We observed no noise, over- or undersense, pace inhibition, or inappropriate shock therapy during 362 fractions of live monitoring. CONCLUSIONS: Reprogrammable CIED reset was the most commonly observed malfunction during proton therapy, and reset risk depended on secondary neutron exposure. The benefits of proton therapy are expected to outweigh the risk of CIED malfunctioning for most patients.

Long-term follow-up of women with early onset pre-eclampsia shows subclinical impairment of the left ventricular function by two-dimensional speckle tracking echocardiography.

OBJECTIVES: This study compares differences in the long-term myocardial function between women with early (EOPE) and late onset preeclampsia (LOPE) and age matched normotensive controls using two-dimensional speckle tracking echocardiography. METHODS: The study population comprised 93 women who gave birth at Department of Gynecology and Obstetrics, Randers Regional Hospital between 1998 and 2008. The women were grouped as EOPE (n = 31), LOPE (n = 22), and women with previous normotensive pregnancies (n = 40). All women underwent comprehensive blinded echocardiographic assessment of myocardial function. RESULTS: The median time since delivery was 12 years [9;15]. Left ventricular (LV) ejection fraction did not differ between groups. In contrast, LV longitudinal systolic myocardial function by LV global longitudinal strain (LVGLS) magnitude was significantly lower in EOPE women than controls (-18 ±â€¯3% versus -21 ±â€¯2%, p < 0.001) and LOPE women (-18 ±â€¯3% versus -21 ±â€¯2%, p < 0.01). In alignment with systolic parameters, the diastolic filling pattern indicated more restrictive filling pattern in EOPE women than controls and LOPE women. Thus, EOPE women had lower septal e' velocities leading to lower mean e' and subsequently higher E/e' ratio (p < 0.01) than controls and LOPE women. LVGLS was the echocardiographic parameter with the strongest association with EOPE in ROC curves. CONCLUSIONS: Women with a history of EOPE are more likely to have subclinical impairment of left ventricular function 12 years after PE than are those with a history of LOPE and controls. LVGLS was the echocardiographic parameter with the strongest association with EOPE.

Can we Save the rectum by watchful waiting or TransAnal microsurgery following (chemo) Radiotherapy versus Total mesorectal excision for early REctal Cancer (STAR-TREC study)?: protocol for a multicentre, randomised feasibility study.

INTRODUCTION: Total mesorectal excision (TME) is the highly effective standard treatment for rectal cancer but is associated with significant morbidity and may be overtreatment for low-risk cancers. This study is designed to determine the feasibility of international recruitment in a study comparing organ-saving approaches versus standard TME surgery. METHODS AND ANALYSIS: STAR-TREC trial is a multicentre international randomised, three-arm parallel, phase II feasibility study in patients with biopsy-proven adenocarcinoma of the rectum. The trial is coordinated from Birmingham, UK with national hubs in Radboudumc (the Netherlands) and Odense University Hospital Svendborg UMC (Denmark). Patients with rectal cancer, staged by CT and MRI as ≤cT3b (up to 5 mm of extramural spread) N0 M0 can be included. Patients will be randomised to either standard TME surgery (control), organ-saving treatment using long-course concurrent chemoradiation or organ-saving treatment using short-course radiotherapy. For patients treated with an organ-saving strategy, clinical response to (chemo)radiotherapy determines the next treatment step. An active surveillance regime will be performed in the case of a complete clinical regression. In the case of incomplete clinical regression, patients will proceed to local excision using an optimised platform such as transanal endoscopic microsurgery or other transanal techniques (eg, transanal endoscopic operation or transanal minimally invasive surgery). The primary endpoint of this phase II study is to demonstrate sufficient international recruitment in order to sustain a phase III study incorporating pelvic failure as the primary endpoint. Success in phase II is defined as randomisation of at least four cases per month internationally in year 1, rising to at least six cases per month internationally during year 2. ETHICS AND DISSEMINATION: The medical ethical committees of all the participating countries have approved the study protocol. Results of the primary and secondary endpoints will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN14240288, 20 October 2016. NCT02945566; Pre-results, October 2016.