Breast cancer

In the framework of this workpackage, the following clinical trials are either ongoing or planned.

The DBCG RT Skagen trial 1 - NCT02384733

RCT offered to BC pts treated with loco-regional RT, and is a randomisation 50 Gy/25 vs 40 Gy/15 fr (boost is simultaneous). Primary endpoint is arm lymph edema. All Danish depts. participate (except Herlev), and pts are enrolled in N, D, B, Slo, Po, and from 2018 Finland and Australia. Now 1200 pts are included. Accrual stops in 2020 with ~3000 pts, where first results are available.

The DBCG RT Senomac trial 

RCT offered to cN0 BC pts, where SN reveals 1-2 macromets. Randomisation is ALND vs no ALND. Pts not having ALND receive level 1 RT. Primary endpoint is distant failure. Pts can be included in Skagen Trial also.

The DBCG RT Heart NTCP study 

This is a retrospective West Danish (Funen & Jutland) cohort study investigating RT dose in the exact location of a heart disease diagnosed following RT for BC. From the West Danish Heart Database almost 4000 invasive heart procedures have been identified in BC pts treated 1990-2015 (>90.000 pts), and this study will try establish a NTCP model linking dose to structures in the heart with risk of radiation-induced heart disease. This PhD study will start summer 2018.

The DBCG RT Recon trial 

RCT offered to BC pts who are candidates for mastectomy and loco-regional RT. Randomisation is immediate vs delayed-immediate reconstruction in relation to timing of RT. Primary endpoint is any complication after reconstruction where a surgical intervention is needed. RT planning is complicated and currently an ESTRO study is ongoing to reach international consensus. The consensus RT will be used in the trial. Around 750 pts will be included.

The DBCG RT Natural trial - NCT03646955

RCT offered to highly selected BC pts (>=60 yr, pT1, pN0, non-lobular, grade 1-2, ER>10%, HER2-, margin >=2mm). Randomisation is PBI vs no PBI. Primary endpoint is 5 yr local recurrence.  All enrolled pts will be offered yearly screen mammography independent of randomisation arm.

The DBCG RT DCIS study 

Prospective nationwide cohort study testing omission of RT in pts operated with breast conservation for DCIS up to 25mm, van Nuys 1-2, margin >=2mm, age >=50 yr, screen detected. Recurrence pattern in DCIS pts treated with RT 2008-2017 is currently being investigated and decision on selection criteria depend on that.

The DBCG RT Proton trial - NCT04291378

A phase 2 study is planned to provide data before a phase 3 study is designed. The phase 2 study will include 100 BC pts who need loco-regional RT, and where IMN RT is indicated. If heart and/or lung constraints are violated after full inclusion of the IMN, the pt must be referred for proton therapy.    

The DBCG RT Nation study 

During 2008-2017 >12.000 BC pts have had loco-regional RT in DK. These RT plans are collected and 3 studies performed:  1) Phase 4 study on IMN RT, 2) Evaluation of Ca scores in the planning CT scan and influence on RT related heart morbidity, 3) pulmonary morbidities following a large low dose bath to the lung after using inverse RT techniques.     

The DBCG RT PRO study (WP 7) 

Please, see WP7

The DBCG RT Shared Decision study 

A generic tool for shared decision making (SDM) offered to BC pts who are candidates for adjuvant RT will be developed, tested and validated in a prospective study. The aim is to introduce SDM to pts being offered RT through an evidence generating nationwide study.

DBCG Hypo trial - NCT00909818

DBCG PBI trial - NCT00892814

Expected results

Based on these DBCG studies, the DBCG RT Committee wants to further develop and explore BC RT. The results will document morbidities and recurrences in modern treated BC pts receiving multimodal therapy. Most of the pts are expected to have no recurrence and few late side effects, but it will be possible to identify pts who suffer from moderate/severe late effects and hopefully offer them relevant therapies (or design future studies to explore treatment of the late effects). The results are expected to validate new target volume definitions, where smaller volumes are irradiated without increasing risks of recurrence. It may be possible to identify pts at high risk of late morbidity based on data from the RT plan, and potentially initiate preventive strategies. Finally, SDM will be introduced in a controlled manner. 

Impact/Relevance/Ethics

The studies will be practice changing, and the results are expected to document that DBCG RT is "cutting edge". The projects have high clinical relevance and will apply with all ethical standards.