Omission of Axillary Surgery in Breast Cancer Patients

KK Women's and Children's Hospital

Status: Enrolling

Conditions: Sentinel Lymph Node; Breast Cancer; Breast Neoplasms

Treatments: Procedure: omission of SLNB in SentiOMIT or omission of ALND in SentiMACRO

Study type: Interventional

Funder types: Other

Identifiers

NCT06259513

CIRB Ref: 2023/2735

Details and patient eligibility

About

The treatment and prognosis of breast cancer (BC) are dependent on its molecular subtype and nodal burden. In early BCs with favourable molecular subtype, the incidence of axillary node involvement is low. However, these patients are still subjected to an axillary operation, which can result in additional cost, operating time and morbidities. Similarly, in patients with limited nodal burden of 1-2 metastatic nodes, there is emerging evidence that these patients may need sentinel lymph node biopsy (SLNB) only, instead of an axillary clearance (AC), which has more surgical morbidities.

We aimed to determine if axillary surgery could be safely tailored in BC patients based on their molecular subtype and nodal burden, without compromising their oncological outcomes. This could in turn reduce the morbidities associated with the axillary surgery,

Total 350 patients will be enrolled. 50 patients with early BC and favourable molecular subtype will be enrolled in a pilot study A (SentiOMIT), whereby SLNB is omitted. For eligible patients who declined study A and other stage I-II patients, with preoperative N0 status, undergoing upfront surgery but did not meet the inclusion criteria of Study A, these patients will be enrolled into study B (SentiMACRO) to undergo SLNB.

In study B, the patients will be categorized based on SLNB into 3 groups with 100 patients in each arm: B1 with pN0, B2- 1-2 metastatic nodes and B3- >/=3 metastatic nodes. In Study B, we aim to investigate if the B2 group (100 patients) can be treated with a less invasive procedure of SLNB alone instead of AC, without affecting oncological outcomes. B1 and B3 are controls.

The outcomes for study A and B include short term outcomes such as morbidity rates, cost and operating time savings. Long term outcomes include recurrence and survival rates. This study will allow individualisation of axillary surgery based on the patient's molecular subtype and nodal burden, to benefit patients' care.

Enrollment: 350 estimated patients

Sex: Female

Ages: 21 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• female patients aged >/=55 years old
• unifocal cancer on imaging
• breast tumour size based on imaging of </=3cm
• no evidence of axillary adenopathy on imaging
• patients with strongly positive ER and PR and negative HER2 on biopsy
• grade 1-2 tumour on core biopsy
• patient who opt for mastectomy

Exclusion criteria

• patients with T3/T4 or stage IV disease, patients with preoperative known N+ disease, bilateral breast cancers, patients planned for neoadjuvant chemotherapy, patients with other malignancies.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: Single Blind

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350 participants in 4 patient groups

patients with omission of SLNB

Experimental group

Description:

early breast cancer patients with cT1-2N0 Luminal A subtype with omission of SLNB

Treatment:

Procedure: omission of SLNB in SentiOMIT or omission of ALND in SentiMACRO

patients with </=2 macrometastasis and omission of ALND

Experimental group

Description:

breast cancer patients with 1-2 macrometastasis on SLNB and had omission of ALND

Treatment:

Procedure: omission of SLNB in SentiOMIT or omission of ALND in SentiMACRO

patients with cT1-2N0 and SLNB

No Intervention group

Description:

early breast cancer patients with cT1-2N0 Luminal A subtype and SLNB

patients with </=2 macrometastasis and ALND

No Intervention group

Description:

breast cancer patients with 1-2 macrometastasis on SLNB and had ALND