Early breast cancer

Question 1

Which factors influence risk for breast cancer recurrence?

Answer 1

Patient characteristics : Age, Menopausal status
Tumor characteristics : Size, Nodal status, Grade, LVSI, Genomic risk score, Receptor status
Treatment related factors: surgical margin, systemic therapy

Question 2

Which group of patients seems to benefit from RT in early breast cancer after BCS?

Answer 2

According to EBCTCG metaanalysis (Lancet 2011), there is highest RT benefit in younger patients, high grade, large tumors, and tumors that do not receive tamoxifen.

Question 3

RT after BCS in early breast cancer

Answer 3

Question 4

RT after BCS: Whole breast irradiation (AGO 2023)

Answer 4

Moderately hypofract. RT (40Gy in 15-16Fx)
Ultrahypofract. RT (26Gy in 5 Fx over one week)
Conventionally fract. RT (50Gy in 25 Fx)
In case of life expectancy <10 yrs and pT1, pN0, R0, ER/PR-positive, HER2-negative, endocrine therapy (all criteria), RT can be omitted, resulting in an increased risk for in-breast recurrence.

Question 5

Which studies investigate the omission of RT in older women with hormone receptor-positive early breast cancer?

Answer 5

CALGB 9343 (Hughes et al, JCO 2013)
PRIME-II Study (Kunkler et al, NEJM 2023)

Question 6

Are there subgroups of patients who may be treated with BCS without radiation in early breast cancer?

Answer 6

There are two trials looking at this question: PRIME II and CALGB 9343

Question 7

Prime-II Study

Answer 7

Phase 3 randomized study
Age > 65 yrs, ER-positive, cN0, T1-2 (upto 3cm), BET and endocrine therapy
WBRT versus no WBRT with 1326 pts
Conclusion: local breast cancer recurrence within 10 years was 9.5% in non-RT-group vs. 0.9% RT-group. OS identical.

Question 8

CALGB 9343

Answer 8

Was designed to determine whether there is a benefit to adjuvant RT after BCS and tamoxifen in women age ≥ 70 years with early-stage breast cancer.

Question 9

CALGB 9343 : Inclusion criteria

Answer 9

636 pts, age > 70, T1N0M0, ER-positive, Lumpectomy
Tamoxifen + RT (TamRT) vs. Tamoxifen (Tam) alone

Question 10

CALGB 9343 : Results

Answer 10

Question 11

CALGB 9343 : Conclusion

Answer 11

At 10yr follow-up 98% TamRT and 90% Tam were free from local and regional recurrences. Hence small improvement in locoregional recurrence. OS identical.

Question 12

Risk of ischemic heart disease in women after radiotherapy for breast cancer

Answer 12

For each gray-increase in the mean heart dose, there is a 7.4% increase of the coronary heart event. That why we say that the mean heart dose should be less than 5, ideally 3 Gy. Careful in patients with known CAD.
Darby NEJM 2013

Question 13

Use of a bisphosphonate (PO/IV) or denosumab in breast cancer

Answer 13

To maintain or improve bone mineral density and reduce risk of fractures in postmenopausal (natural or induced) patients receiving adjuvant aromatase inhibitor therapy