* Structure: CQ sentence, recommendation, strength of recommendation (Table 2 shows recommendation grades.), and strength of evidence. (Table 3 shows strength of evidence.)
Table 2 Recommendation grade Table 3 Strength of evidence Breast surgery in the initial treatment of breast cancer
CQ1: Is surgery recommended for patients with non-invasive ductal cancer (ductal carcinoma in situ: DCIS)?
(Recommendation) Surgery for patients with non-invasive ductal carcinoma is weakly recommended. [Strength of recommendation (SoR): 3, strength of evidence (SoE): very weak]
CQ2: In breast-conserving surgery (BCS) for invasive/non-invasive ductal carcinoma, is additional surgery recommended for patients with positive surgical margins?
(Recommendation) Additional surgery is weakly recommended for patients with positive surgical margins in BCS. (SoR: 2, SoE: weak)
CQ3: Is skin-sparing or nipple/areola-sparing mastectomy recommended in breast reconstruction?
CQ3a: Is skin-sparing mastectomy (SSM) recommended?
(Recommendation) Skin-sparing mastectomy is weakly recommended. (SoR: 2, SoE: weak)
CQ3b: Is nipple-sparing mastectomy (NSM) recommended?
(Recommendation) Nipple-sparing mastectomy is weakly recommended. (SoR: 2, SoE: weak)
Axillary surgery in the initial treatment of breast cancer
CQ4: Is no further axillary surgery for patients with sentinel node metastasis recommended?
CQ4a: In cases of micrometastases
(Recommendation) Is no further axillary surgery is strongly recommended. (SoR: 1, SoE: moderate)
CQ4b: In cases of macrometastases
CQ4b-1: Breast-conserving therapy
(Recommendation) Is no further axillary surgery is weakly recommended. (SoR: 2, SoE: moderate)
CQ4b-2: Total mastectomy (without radiation therapy)
(Recommendation) Further axillary surgery is strongly recommended. (SoR: 4, SoE: very weak)
CQ4b-3: Total mastectomy (with radiation therapy)
(Recommendation) Is no further axillary surgery is weakly recommended. (SoR: 2, SoE: weak)
CQ5: Is sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) recommended for avoidance of ALND?
CQ5a: Is SLNB for clinical node-negative breast cancer before and after NAC recommended?
(Recommendation) SLNB is weakly recommended. (SoR: 2, SoE: weak)
CQ5b: Is SLNB recommended, if an ipsilateral axillary lymph node is initially positive, and it is clinically negative after NAC?
(Recommendation) It is weakly recommended not to perform SLNB (recommended to perform ALND) (SoR: 3, SoE: weak)
Breast reconstruction in the initial treatment of breast cancer
CQ6: Is immediate breast reconstruction recommended after total mastectomy for clinically node-positive breast cancer patients who desire breast reconstruction?
(Recommendation) Immediate breast reconstruction after total mastectomy is weakly recommended for breast cancer patients with node-positive breast cancer who desire breast reconstruction. (SoR: 2, SoE: weak)
Surgery for metastatic and recurrent breast cancer
CQ7: Is primary tumor resection to improve prognosis recommended for Stage IV breast cancer?
(Recommendation) It is weakly recommended not to perform primary tumor resection to improve prognosis for Stage IV breast cancer. (SoR: 3, SoE: moderate)
CQ8: Is surgical resection recommended for regional lymph node recurrence?
CQ8a: For ipsilateral axillary lymph node recurrence after ALND
(Recommendation) Surgical resection is weakly recommended. (SoR: 2, SoE: very weak)
CQ8b: For ipsilateral supraclavicular lymph node recurrence
(Recommendation) It is weakly recommended not to perform surgical resection. (SoR: 3, SoE: very weak)