Inflammatory breast cancer

Definition

• Clinicopathological entity of breast cancer with erythema and oedema over at least one third of the breast, classified as T4d in the TNM system.

Classification

• Diagnostic criteria are a rapid onset of erythema, oedema, peau d'orange or warmth with or without a palpable mass, a history of no more than six months, erythema of at least one third of the breast and histological confirmation of invasive carcinoma.
• The primary form develops in a previously normal breast, the secondary form as inflammatory skin change in a breast with known invasive cancer.

Occurrence & epidemiology

Epidemiology

• Inflammatory breast cancer accounts for about 1–5% of breast cancers in the United States, depending on the source, but for about 7% of breast cancer deaths.
• It is often diagnosed at a younger age and is more common and diagnosed earlier in Black women than in White women.

Aetiopathogenesis

Aetiology and pathogenesis

• The cause is unknown; the disease is more common in women with obesity.
• The typical picture arises because tumour cells block the lymphatic vessels of the skin; most tumours are invasive ductal carcinomas and often hormone receptor-negative.

Clinical features

Distinction from inflammation

• Inflammatory breast cancer presents with diffuse erythema over at least one-third of the breast with oedema and peau d'orange, characteristically without fever.
• Inflammatory carcinoma is confirmed by a punch biopsy of the skin showing lymphatic vessel invasion, as a discrete mass is often absent.
• Paget's disease of the nipple is an intraepidermal spread of carcinoma cells and thus a sign of cancer, not a dermatosis.

• Symptoms develop rapidly; the breast is red and swollen, enlarges rapidly and shows peau d'orange, and there is usually no palpable lump.
• Further features are heaviness, burning or tenderness, an inverted nipple and enlarged lymph nodes in the axilla or near the collarbone.
• At diagnosis the disease is at least stage IIIB; most patients have locoregional disease, and up to 40% already have distant metastases.

Diagnosis

Typical imaging findings

• Clinical finding: The breast is diffusely red over a wide area, clearly enlarged and warm. The skin is thickened with coarse pitting — the peau d'orange appearance; the redness involves more than a third of the breast and there is no circumscribed mass.

• Mammography frequently shows skin thickening (84–93%), increased density (93%) and axillary adenopathy (24%), and ultrasound shows skin thickening, hypoechoic non-mass abnormalities, calcifications and nodal disease.
• The diagnosis is confirmed by core needle biopsy, supplemented by a skin punch biopsy from the most affected area; tumour cell emboli in dermal lymphatics are typical but not required for the diagnosis.

Keep learning in the app

Further reading (selection)

1. StatPearls: Inflammatory Breast Cancer (NCBI Bookshelf)
2. National Cancer Institute: Inflammatory Breast Cancer
3. Inflammatory breast cancer, best practice in the community setting (NPJ Breast Cancer 2025, PubMed Central)
4. DocCheck Flexikon, Mastitis non-puerperalis

Cross-references