Comparison of Acute Toxicity and Cost Between Whole Breast Irradiation With Sequential Boost and Simultaneous Integrated Boost After Breast Conserving Surgery. (SeqB vs SIB)

Ghent University Hospital (UZ)

Status and phase: Completed; Phase 2

Conditions: Radiotherapy After Breast Conserving Surgery

Treatments: Radiation: SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.12 Gy); Radiation: SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.33 Gy); Radiation: sequential boost (15 x 2.67 Gy WBI + 4 x 2.5 Gy boost); Radiation: sequential boost (15 x 2.67 Gy WBI + 6 x 2.48 Gy boost)

Study type: Interventional

Funder types: Other

Identifiers

NCT01973634

2012/655

Details and patient eligibility

About

Whole breast irradiation (WBI) after breast conserving surgery for early-stage breast cancer halves the recurrence risk and reduces the breast cancer death by about one sixth. A sequential boost (SeqB) dose to the tumour bed further improves local control, but also increases the risk of late skin toxicity and cosmetic changes. At Ghent University Hospital WBI is prescribed in 15 fractions of 2.67 Gy according to the START-B hypofractionation scheme. A sequential boost is typically given in 4 to 8 extra fractions which prolongs the overall treatment time. The boost dose can also be delivered within the 15 fractions of WBI, the so-called simultaneous integrated boost (SIB). SIB shortens the overall treatment time which is convenient for the patient and the radiotherapy department. In this study we wish to test the hypothesis of acceptable skin toxicity and reduced cost with SIB using hypofractionated prone intensity modulation radiotherapy IMRT with topographical dose painting, a technique recently developed in our group. Patients are randomized between SeqB and SIB.

Enrollment: 170 patients

Sex: Female

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Inclusion criteria:

Female patients AND breast conserving surgery AND multidisciplinary decision of adjuvant WBI with a boost to the tumor bed AND age ≥ 18 years AND informed consent obtained, signed and dated before specific protocol procedures

Exclusion criteria

• Mastectomy
• Need for lymph node irradiation
• No boost
• Bilateral breast irradiation
• Patient not able to reach or maintain the prone position
• Pregnant or breastfeeding
• Mental condition rendering the patient unable to understand the nature, scope and possible consequences of the study
• Patient unlikely to comply with the protocol; i.e. uncooperative attitude, inability to return for follow-up visits, and unlikely to complete the study

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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170 participants in 4 patient groups

Minimal surgical margin 1 mm, conventional arm: seq boost

Active Comparator group

Description:

Minimal surgical margin of 1 mm, conventional arm with sequential boost (15 x 2.67 Gy WBI + 4 x 2.5 Gy boost).

Treatment:

Radiation: sequential boost (15 x 2.67 Gy WBI + 4 x 2.5 Gy boost)

Minimal surgical margin of 1 mm, experimental arm with SIB

Experimental group

Description:

Minimal surgical margin of 1 mm, experimental arm with SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.12 Gy)

Treatment:

Radiation: SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.12 Gy)

Minimal surgical margin <1 mm, conventional arm: seq boost

Active Comparator group

Description:

Minimal surgical margin \< 1 mm, conventional arm with sequential boost (15 x 2.67 Gy WBI + 6 x 2.48 Gy boost)

Treatment:

Radiation: sequential boost (15 x 2.67 Gy WBI + 6 x 2.48 Gy boost)

Minimal surgical margin < 1 mm, experimental arm with SIB.

Experimental group

Description:

Minimal surgical margin \< 1 mm, experimental arm with SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.33 Gy)

Treatment:

Radiation: SIB (15 x 2.67 Gy WBI and SIB 15 x 2.67-3.33 Gy)