The 18th St.Gallen International Breast Cancer Conference (SGBCC 2023) was held in Vienna, the “City of Music”, from March 15 to 18, 2023 local time. SGBCC gathered breast cancer opinion leaders from all over the world to discuss and vote on the most cutting-edge and controversial topics related to early-stage breast cancer treatment. This forms the St.Gallen Early Breast Cancer International Expert Consensus, which is updated every two years. “Oncology Frontier” has compiled expert votes on topics related to early breast cancer’s pathology, genes, DCIS, and male-related issues. Let’s experience the St.Gallen atmosphere of early breast cancer treatment decision-making.
Treatment Decision for Triple-Negative Breast Cancer
Pathology:
(1) A 43 year old woman has undergone lumpectomy for a 1.6 cm, node-negative, grade 3, triple negative breast cancer. The sTlL score is 75%. Which of the following would you recommend?
1. Adjuvant chemotherapy
2. Good prognosis, no need for adjuvant chemotherapy
3. Abstain
SGBCC Expert Voting:
(2) Patient has undergone surgery for stage T1b TNBC, measuring 0.8 cm. The tumor has a high TILs > 50%. Which of the following would you recommend?
1. Adjuvant chemotherapy
2. Good prognosis, no need for adjuvant chemotherapy
3. Abstain
SGBCC Expert Voting:
Genetics:
(3) Breast cancer patients should have access to genetic counselors
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
(4) As part of routine care, all patients with breast cancer should ordinarily undergo germline genetic counseling and testing with agene panel testing (8 or 9 genes, including high penetrance and intermediate penetrance genes such as BRCA1, BRCA2 PALB2ATM, and CHEK2), regardless of family history or age:
As part of routine care, all patients with breast cancer should ordinarily undergo germline genetic counseling and may undergo testing for a limited panel of actionable, high-penetrance genes,namely, BRCA1,BRCA2,and PALB2:
As part of routine care, all patients younger than age 70 with breast cancer should ordinarily undergo germline genetic counseling and may undergo testing with a gene panel testing (8or 9 genes, minimum) regardless of family history.
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
(5) You are discussing risk-reducing mastectomy and intensified surveillance with a perimenopausal woman who has been diagnosed with early stage breast cancer. She has had genetic testing, and harbors a deleterious mutation. As part of a shared decision making process, she asks your opinion on management.
For each of these mutations indicate if you would preferentially recommend either contralateral risk-reducing surgery, or intensive (mammogram and MRI-based) screening, or if you have no preference (either)?
1. Surgery
2. Enhanced Screening
3. Abstain
SGBCC Expert Voting:
(6) A patient has developed isolated local regional recurrence 4 years after initial diagnosis while on adjuvant aromatase inhibitor therapy. The tumor is strongly ER positive and HER2 negative. A staging work up is negative. The recurrence is fully exised and receives definitive local therapy. When originally diagnosed, she had not received adjuvant chemotherapy.Would you recommend genomic signature testing to decide whether to receive chemotherapy?
1. Yes, to determine suitability for chemotherapy.
2. No, because chemotherapy would be recommended regardless of resistance to ET.
3. No, because chemotherapy is not recommended.
4. No, clinical decisions will be made based on other factors (tumor grade, Ki67, PR status, age).
5. Depending on the size of the recurrent lesion.
6. Abstain.
SGBCC Expert Voting:
(7) Patients with early breast cancer and pathological PALB2 mutations should be offered adjuvant PARP inhibitar therapy in accordance with the same criterla for adjuvant use in BRCA1/2 mutation carriers recognizine the absenoe of data supporting such are commendation.
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
(8) A patient has undergone hereditary genetic testing and has had tumor genomic testing.There is no hereditary mutation. However, there is a deleterious, somatic tumor mutation in BRCA1.Would you give adjuvant olaparib, if readily available?
1. Yes
2. No
3. Abstain
(9) A patient with a BRCA2 mutation has been diagnosed with ER positive HER2 positive breast cancer, with stage meeting OLYMPIA eligibility and will receive standard adjuvant therapies.Would you recommend adjuvant olaparib, if readily available?
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
Ductal Carcinoma In Situ (DCIS)
(10)A healthy woman has undergone breast conserving surgery for DCIS. The DCIS is grade 1 to 2, without comedonecrosis, and spans less than 2 cm. Should she receive radiation therapy?
If the same patient will take endocrine therapy for ER+ DCIS, Would you recommend radiation therapy?
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
(11) Considering the following DCIS patients who have undergone breast-conserving surgery with margins greater than 2 mm, which patients need radiation therapy? (Age groups are <50 years old, 50~65 years old, >70 years old; DCIS groups are tumor size <2 cm, tumor size ≥2 cm, no comedo necrosis, <2 cm and no comedo necrosis)
1. Yes
2. No
3. Abstain
SGBCC Expert Voting:
(12) A healthy postmenopausal woman has undergone breast conserving surgery and radiation therapy for DCIS.She is discussing adjuvant endocrine therapy with you.Her principal goal is prevention of in breast recurrence.She is concerned about familiar side effects, the modest benefits of endocrine treatment. Which of the following would you recommend?
1. No endocrine therapy
2. Tamoxifen 5 mg daily
3. Tamoxifen 20 mg daily
4. Aromatase inhibitor
5. Either 3 or 4
6. Abstain
SGBCC Expert Voting:
Male Breast Cancer
(13) The preferred local-regional treatment option for male breast cancer in non-BRCA1/2 mutation carriers is:
1. Lumpectomy
2. Lumpectomy combined with radiation
3. Mastectomy
4. Nipple-sparing mastectomy
5. Abstain
SGBCC Expert Voting:
(14) For stage I (excluding minimal risk), ER+/HER2- breast cancer, the preferred adjuvant endocrine therapy for male patients is:
For stage III, ER+/HER2- breast cancer, the preferred adjuvant endocrine therapy for male patients is:
1. Tamoxifen
2. Aromatase inhibitor
3. GnRH agonist combined with Tamoxifen
4. GnRH agonist combined with Aromatase inhibitor
5. Abstain
SGBCC Expert Voting:
SGBCC Expert Voting, which one do you pick?
Due to formatting constraints, we’ve selected a few questions for readers to vote on, letting everyone experience the St. Gallen atmosphere of early breast cancer treatment decisions. The question stems have been abbreviated; for detailed content, please refer to the above text.”
1. 43 years old, Grade 3, TNBC, 1.6 cm, N-, sTlL 75%, what would you recommend? (Choose one)
• Adjuvant chemotherapy
• Good prognosis, no need for adjuvant chemotherapy
• Abstain
2. T1b stage TNBC, 0.8 cm, TIL> 50%, what would you recommend? (Choose one)
• Adjuvant chemotherapy
• Good prognosis, no need for adjuvant chemotherapy
• Abstain
3. 4 years after initial diagnosis, isolated recurrence, should genetic testing be recommended after surgery? (Choose one)
• Yes, to determine if chemotherapy is suitable
• No, because regardless of resistance to ET, chemotherapy would be recommended
• No, because chemotherapy is not recommended
• No, decisions can be made based on other factors (tumor grading, Ki67, PR status, age)
• Depends on the size of the recurrent lesion
• Abstain
4. Should EBC patients with PALB2 mutation be given PARPi adjuvant treatment? (Choose one)
• Yes
• No
• Abstain
5. Should patients with somatic BRCA1 mutation be given olaparib adjuvant treatment? (Choose one)
• Yes
• No
• Abstain
6. BRCA2m+, ER+/HER2+, meets OLYMPIA criteria, would you recommend olaparib? (Choose one)
• Yes
• No
• Abstain
7. After breast-conserving surgery for DCIS Grade 1~2, without comedo-type necrosis, T<2 cm, should radiotherapy be given? (Choose one)
• Yes
• No
• Abstain
8. If the patient has ER+ DCIS and will receive endocrine therapy, would you recommend radiotherapy? (Choose one)
• Yes
• No
• Abstain
“SGBCC voting site (Photography: Maple Leaf).”
