Primary invasive breast cancer

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Last reviewed: 15 Nov 2025

Last updated: 07 Nov 2025

Breast cancer is a malignancy that is often strongly influenced by age, family history, genetic factors, hormonal exposure, and lifestyle factors.

Breast cancer may present as mammographic abnormalities (calcifications with suspicious morphology, mammographic mass, architectural distortion, or asymmetric density) detected at routine screening. Biopsy is required for definitive diagnosis.

Clinical breast exam may demonstrate a firm breast mass, which may be associated with axillary lymphadenopathy, skin changes, and nipple discharge.

Treatment requires a multidisciplinary approach, involving medical oncologists, breast surgeons, and radiation oncologists.

Complications of therapy are specific to each modality of treatment, and careful monitoring and preventive therapy for adverse events (e.g., antiemetic for the prevention of chemotherapy-induced nausea) are essential.

Definition

Primary invasive breast cancer is a malignancy originating in the ducts or lobules. The term "invasive" indicates that the malignancy has penetrated past the basement membrane of the duct or lobule of the breast and has spread to the surrounding tissues, but has not spread to other organs.

The American Joint Committee on Cancer TNM (tumor, node, metastasis) staging system classifies invasive breast cancer into the following stages based on the extent of disease: IA, IB, IIA, IIB, IIIA, IIIB, and IIIC.[1]

Stages IA, IB, and IIA are generally considered early-stage breast cancer. Stages IIIA, IIIB, and IIIC are generally considered locally advanced breast cancer.

Staging can also be defined by the pathologic node status (pN0 - pN3), which is dependent on the number of axillary nodes with metastases.

病史和体格检查

关键诊断因素

breast mass
nipple discharge
axillary lymphadenopathy

完整详情

其他诊断因素

skin thickening or discoloration
retraction, inversion, or scaling of the nipple

完整详情

危险因素

increasing age
female sex
ethnic origin
positive family history of breast and/or other cancers
genetic mutations in breast cancer susceptibility genes
endogenous estrogen exposure
exogenous estrogen/progestin exposure
alcohol consumption
radiation exposure
atypical breast disease
increased breast density
mild, moderate, or marked background parenchymal enhancement (BPE) on breast magnetic resonance imaging (MRI)
reduced physical activity
poor diet
high socioeconomic status
smoking
obesity
high dibutyl-phthalate exposure

完整详情

诊断性检查

首要检查

mammogram

完整详情

需考虑的检查

breast ultrasound
breast MRI
biopsy
hormone receptor testing
HER2 testing
gene expression assays
computed tomography
bone scan
genetic testing
CBC
LFTs
alkaline phosphatase

完整详情

治疗流程

急症处理

early-stage breast cancer (stages I to IIB [T2 N1 M0])

locally advanced breast cancer (stages IIB [T3 N0 M0] to III)

持续性治疗

disease recurrence

撰稿人

作者

Kandace P. McGuire, MD

Professor of Surgery

Virginia Commonwealth University

Richmond

利益声明

KPM is on the Advisory Board for Kubtec and the speaker bureau for Endomag/Hologic.

鸣谢

Dr Kandace McGuire would like to gratefully acknowledge Dr Krystal Cascetta, Professor Amy Tiersten, Dr Hope S. Rugo, Dr Amal Melhem-Bertrandt, Dr Gabriel N. Hortobagyi, and Dr Phuong Khanh H. Morrow, the previous contributors to this topic.

利益声明

KC, AMB, GNH, and PKHM declare that they have no competing interests. AT is on the advisory board for Immunomedics, AstraZeneca, Novartis, Eisai, and Healthline; receives research funding from Pfizer, Novartis, Genentech, Lilly, and AstraZeneca; and does expert testimony work. HSR receives research funding through the University of California from Novartis, Pfizer, Genentech, Macrogenics, Plexxikon, Merck, Nektar, and GSK; has been reimbursed for travel by Novartis, Genentech, and Nektar; and has received speaker honorarium from Genomic Health.

同行评议者

Savannah Liddell, MD

Fellow

Mayo Clinic College of Medicine and Science

Rochester

利益声明

SL declares that she has no competing interests.

Katherine H.R. Tkaczuk, MD, FACP

Professor of Medicine

University of Maryland School of Medicine

Baltimore

Disclosures

KHRT declares that she has no competing interests.

Susan Tannenbaum, MD

Associate Professor, Medicine

Chief, Division of Hematology/Oncology

Medical Director, Neag Comprehensive Cancer Center

University of Connecticut

Farmington

Disclosures

ST declares that she has no competing interests.

Emily Hsu, MD

Fellow

Division of Hematology/Oncology

University of Connecticut

Farmington

Disclosures

EH declares that she has no competing interests.

Anees Chagpar, MD

Assistant Professor

University of Louisville

Louisville

Disclosures

AC declares that she has no competing interests.

Gurhan Celik, MD

General Surgeon

General Surgery Department

Istanbul Training and Research Hospital

Istanbul

Turkey

Disclosures

GC is an author of a number of references cited in this topic.

Edward R. Sauter, MD, PhD

Medical Officer

Breast and Gynecologic Cancer Working Group

Division of Cancer Prevention

National Cancer Institute

Bethesda

Disclosures

ERS declares that he has no competing interests.

Peer reviewer acknowledgements

BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.

Disclosures

Peer reviewer affiliations and disclosures pertain to the time of the review.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: breast cancer screening and diagnosis [internet publication].Full text

National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: breast cancer [internet publication].Full text

Loibl S, André F, Bachelot T, et al. Early breast cancer: ESMO clinical practice guideline for diagnosis, treatment and follow-up. Ann Oncol. 2024 Feb;35(2):159-82.Full text Abstract

Denduluri N, Somerfield MR, Eisen A, et al. Selection of optimal adjuvant chemotherapy regimens for human epidermal growth factor receptor 2 (HER2)-negative and adjuvant targeted therapy for HER2-positive breast cancers: an American Society of Clinical Oncology guideline adaptation of the Cancer Care Ontario clinical practice guideline. J Clin Oncol. 2016 Jul 10;34(20):2416-27.Full text Abstract

Park KU, Somerfield MR, Anne N, et al. Sentinel lymph node biopsy in early-stage breast cancer: ASCO guideline update. J Clin Oncol. 2025 May 10;43(14):1720-41.Full text Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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Primary invasive breast cancer

Summary

Definition

病史和体格检查

关键诊断因素

其他诊断因素

危险因素

诊断性检查

首要检查

需考虑的检查

治疗流程

early-stage breast cancer (stages I to IIB [T2 N1 M0])

locally advanced breast cancer (stages IIB [T3 N0 M0] to III)

disease recurrence

撰稿人

作者

Kandace P. McGuire, MD

利益声明

鸣谢

利益声明

同行评议者

Savannah Liddell, MD

利益声明

Katherine H.R. Tkaczuk, MD, FACP

Disclosures

Susan Tannenbaum, MD

Disclosures

Emily Hsu, MD

Disclosures

Anees Chagpar, MD

Disclosures

Gurhan Celik, MD

Disclosures

Edward R. Sauter, MD, PhD

Disclosures

Peer reviewer acknowledgements

Disclosures

References

Key articles

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

Differentials

Guidelines

Patient information

Log in or subscribe to access all of BMJ Best Practice

Log in or subscribe to access all of BMJ Best Practice

Log in to access all of BMJ Best Practice