Chest wall radiotherapy after mastectomy treats a thin, curved target that includes the skin and scar. Bolus, reconstruction and field matching with nodal volumes make it one of the more technique-sensitive breast plans.
After mastectomy the target is the chest wall: the skin, the scar and the thin layer of tissue over the ribs. It is shallow and curved, and often sits over a breast reconstruction.
Common schedules include 50 Gy in 25 fractions, 40.05 Gy in 15 fractions and 26 Gy in 5 fractions for the chest wall.
What changes for the planner:
As for whole breast, with the scar and skin in focus.
Supine on a breast board with the arm above the head, scanned from the neck to below the diaphragm. More →
The same reproducibility and breath-hold considerations as whole-breast treatment.
Radio-opaque wire on the mastectomy scar, and optionally around the opposite breast.
Shows the scar and the expected chest wall extent on CT, and makes the contralateral breast easier to see and spare.
Tissue-equivalent material placed on the skin during treatment. More →
Megavoltage beams deposit less dose at the surface. When the skin needs full dose, bolus moves the build-up region outward. Chest wall bolus should be considered; international consensus covers when it is used.
An implant, tissue expander or tissue flap placed at or after mastectomy. More →
Reconstruction changes the shape of the chest wall and where the target lies relative to the implant. A consensus guideline covers delineation after implant-based reconstruction.
Image fusion aligns an outside scan with the planning CT so the target can be drawn using information the CT doesn't show. After mastectomy the breast is gone, so the pre-operative imaging — mammogram, ultrasound, MRI or PET/CT — is mainly reviewed alongside the planning CT rather than relied on for a close match.
It shows where the tumor was and how far it extended, and any involved nodes. The chest wall and nodal targets are drawn on the planning CT, guided by the scar wire and anatomy.
What each volume represents. Expansions and dose levels come from your protocol.
The tissue left after mastectomy, including the scar, down to the chest wall.
Atlases differ on the deep border and on how reconstruction is handled, which changes lung and heart dose.
The CTV expanded for setup uncertainty, and an evaluation copy used to judge coverage.
Whether the evaluation volume is cropped from the skin depends on whether bolus is used and on your protocol.
Chest wall without nodes. Click an organ for its anatomy, why it matters and contouring resources. Superscripts link to the study behind each value.
| Organ | 50 Gy / 25 fx | 26 Gy / 5 fxFAST-Forward |
|---|---|---|
| Ipsilateral Lung25 fx limits are from a whole-breast tangent trial. With nodes, V20 Gy <30% applies — see the regional nodal page. |
| |
| Contralateral Lung |
| — |
| Heart / PericardiumKeep mean dose as low as reasonably achievable; <2 Gy is often achievable. Consider breath hold. | ||
| LAD (Left Anterior Descending Artery)Left-sided treatment. Developed mainly for whole-breast plans. | — | |
| Contralateral BreastKeep as low as reasonably achievable, especially with VMAT or fields crossing the midline. | — |
Values quoted from RTOG 1005, eviQ 1925 (last reviewed 28 March 2024; review due 30 June 2028), DEGRO 2019 and SKAGEN Trial 1, checked by DoseLab on 2026-09-23. Verify against your protocol, institutional policy and physician directive before clinical use.
ESTRO ACROP consensus on post-mastectomy target delineation after implant-based immediate reconstruction. Citation as given in the eviQ reference list; not yet checked against the journal.
Delphi consensus recommendations on the use of bolus in post-mastectomy radiotherapy. Citation as given in the eviQ reference list; not yet checked against the journal.
Five-year results of the UK FAST-Forward trial, comparing one week of whole-breast or chest wall radiotherapy with three weeks. Citation as given in the eviQ reference list; not yet checked against the journal.
NRG Oncology's protocol page for RTOG 1005, a phase 3 trial of hypofractionated whole-breast irradiation with a concurrent (SIB) boost. The protocol document holds the trial's dose–volume requirements, set separately for each arm: Arm I (50 Gy in 25 fractions, sequential boost) and Arm II (40 Gy in 15 fractions, concurrent boost to 48 Gy). Both arms are tangent-style whole-breast treatment without nodes, and skin bolus was not allowed. DoseLab checked the 50 Gy / 25 fx ipsilateral lung limits against section 6.4.3.5 of the 24 May 2011 version.
NRG Oncology's protocol page for NSABP B-51 / RTOG 1304, a phase 3 trial of regional nodal irradiation after neoadjuvant chemotherapy. The protocol document holds the trial's normal-tissue requirements.
NRG Oncology's breast downloads page, which links the RTOG Breast Cancer Atlas for Radiation Therapy Planning, an NRG whole-breast radiation therapy template and the RADCOMP breast atlas.
Endorsed eviQ protocol for chest wall radiotherapy after mastectomy. DoseLab's post-mastectomy constraint table reproduces selected values from its organs-at-risk table, keeping eviQ's citation for each. When nodes are treated, the protocol refers to its nodal irradiation protocol for organ limits.