Refusal of Breast Surgery in Patients With Breast Cancer With a Clinical Complete Response (cCR) After Neoadjuvant Systemic Therapy and a Confirmed Pathological Complete Response (pCR) Using Vacuum-assisted Biopsy (VAB) and Sentinel Lymph Node Biopsy (SLNB)
Refusal of Breast Surgery in Patients With Breast Cancer With a Clinical Complete Response (cCR) After Neoadjuvant Systemic Therapy and a Confirmed Pathological Complete Response (pCR) Using Vacuum-assisted Biopsy (VAB) and Sentinel Lymph Node Biopsy (SLNB)
The main goal of the study is to abandon breast surgery in patients with breast cancer with a
 clinical complete response (cCR) after neoadjuvant systemic therapy and confirmed pCR using
 Vacuum-assisted biopsy (VAB) and sentinel lymph node biopsy (SLNB).

 Evidence of the high diagnostic accuracy (sensitivity and specificity) of vacuum aspiration
 biopsy in determining pCR in patients with clinical complete response after neoadjuvant
 systemic therapy will allow abandoning breast surgery in favor of radiation therapy alone,
 improving the quality of life of these patients.
Vacuum-assisted removal and biopsy of the tumor bed after neoadjuvant systemic therapy (NST)
 in patients with clinical complete clinical response with a biopsy of sientinel lymph nodes
 is in the future a modern alternative to the standard, often crippling and traumatic surgical
 procedures and does not require additional financial costs for the reconstruction of the
 breast.

 There are only two trial visits that are specific to the trial. All other visits will be
 routine visits.

 The first trial visit before NST will take place in order to provide the patient with
 detailed information on the study, its' aims, the VAB procedure, and its risks. The patient
 will be asked to sign a form of informed consent.

 In the second visit after the NST, VAB planning will be carried out. This visit may vary
 depending on the patient, the tumor, and the characteristics of the study site. We will
 provide each test participant with the opportunity to choose the appropriate conditions for
 the procedure.

 The VAB procedure with a sentinel lymph node biopsy will be performed in the operating room
 Research objectives

 1. To evaluate the frequency of coincidence of the clinical complete or partial response
 (cCR and PR) with pathological complete response (pCR).

 2. To study the frequency of detecting a residual tumor in the mammary gland using a
 Vacuum-assisted biopsy or another type of core biopsy and / or detection of metastases
 in regional lymph nodes (sentinel lymph node biopsy) in comparison with a standard
 pathological study of the surgical material and regional (including sentinel ) lymph
 nodes.

 3. To analyze the frequency of false-positive conclusions of a vacuum aspiration biopsy of
 the tumor bed about the achievement of pathological complete response (pCR) in
 comparison with a standard pathological study of a surgical material.

 4. To study the long-term results (local-regional relapse, survival) of surgical treatment
 of patients with clinical complete response (cCR) after neoadjuvant systemic therapy,
 including residual disease compared with patients who achieved pathological complete
 response (pCR).

 5. To develop an algorithm for treating patients with clinical complete response, with a
 confirmed pathological complete response using a tumor bed biopsy and targeted biopsy of
 sentinel lymph nodes (taking into account the initial characteristics: age, stage with
 TNM, disease subtypes, the presence of a genetic mutation BRCA1 / 2).

 Ultrasound guided VAB will be performed on breast cancer patients with clinical complete
 response (cCR) after NST.

 The pathological results of the VAB specimen will be generally categorized as follows:

 1. Residual tumor cells in VAB specimen (=non-pCR)

 2. No residual tumor cells in the VAB specimen and VAB representative of former tumor
 region (="pCR in VAB")

 3. No residual tumor cells in the VAB specimen but VAB unclear or not representative of
 former tumor region (=possible sampling error). These VABs are categorized as
 uninformative for the primary endpoint of the clinical trial.

 The results will be compared with the results of a pathological examination of a surgical
 material.
Inclusion Criteria:

 Triple negative breast cancer / HER2-positive breast cancer (ER / PR +/-)

 -  age> 18 years.

 -  morphologically confirmed diagnosis of breast cancer, IIA-IIIA stage

 -  ECOG score 0-1.

 -  life expectancy of more than 3 months.

 -  the consent of patients to use reliable methods of contraception throughout the study

 -  adequate liver and bone marrow function

 -  the absence of contraindications to surgical intervention (including anesthetic risk
 is taken into account).

 Exclusion Criteria:

 -  Inconsistency with inclusion criteria.

 -  Conducting earlier any systemic therapy for breast cancer.

 -  stage 4 cancer

 -  carrier mutations of the BRCA1 / 2 gene

 -  severe uncontrolled concomitant chronic diseases or acute diseases

 -  the presence of a second malignant tumor

 -  pregnancy or lactation

 -  acute conditions and complications, which, according to the doctor, interfere with
 treatment