Inflammatory breast cancer

😠 Pathology - The Angry Breast

• Core Pathology: An aggressive ductal carcinoma defined by diffuse invasion and obstruction of dermal lymphatic vessels by tumor emboli.
• Mechanism: Lymphatic blockage → impaired drainage → lymphedema, erythema, and warmth, creating the "inflammatory" signs.
• Histology: Punch biopsy is diagnostic, showing malignant cells within dermal lymphatics. Often lacks a discrete palpable mass.
• Clinical Mimic: Presents acutely like mastitis but fails to resolve with antibiotics.

⭐ Key Feature: The characteristic peau d'orange (orange peel) appearance is due to lymphedema causing skin tethering around hair follicles.

😠 Clinical Manifestations - Red, Swollen, Unhappy

• Rapid Onset: Symptoms develop acutely over days to weeks.
• Diffuse Breast Changes:
  • Erythema (redness), edema (swelling), and warmth involving ≥1/3 of the breast.
  • Tenderness and firmness.
  • A discrete palpable mass is often absent.
• Pathognomonic Sign:
  • Peau d'orange: A dimpled, pitted skin appearance from dermal lymphatic invasion by tumor cells.
• Other Signs: Nipple retraction/inversion, axillary lymphadenopathy.

⭐ High-Yield: IBC is a clinical diagnosis that mimics mastitis. Suspect it in a non-lactating woman with "mastitis" that fails to improve after 1-2 weeks of antibiotics.

🔬 Diagnosis - Biopsy is Boss

⚠️ Critical: IBC is often misdiagnosed as mastitis. Failure to improve after 3-5 days of antibiotics mandates immediate workup for IBC.

• Initial Steps:

  • Diagnostic Mammogram & Ultrasound: Often reveals skin thickening, diffuse increased breast density, and axillary adenopathy. A discrete mass may be absent.

• Biopsy is Mandatory for Diagnosis:

  • Full-thickness punch biopsy of the involved skin is essential, even without a clear mass.
  • Core needle biopsy of any underlying mass or suspicious sonographic finding.
  • Biopsy confirms malignancy and determines receptor status (ER, PR, HER2).

⭐ Pathognomonic Finding: The presence of tumor emboli invading the dermal lymphatic vessels on skin punch biopsy confirms the diagnosis.

🥊 Management - Triple Threat Takedown

IBC requires an aggressive, mandatory trimodal approach. The specific sequence is critical for survival and local control. 📌 Mnemonic: C-S-R (Chemotherapy → Surgery → Radiation).

⭐ High-Yield Rule: Surgery is NEVER the first step. Initial mastectomy is contraindicated as it fails to address the diffuse dermal lymphatic tumor emboli and is associated with very poor outcomes. Always begin with systemic chemotherapy to downstage the tumor and treat micrometastases.

• Surgical Standard: Modified Radical Mastectomy (MRM) is required; breast conservation is not an option due to diffuse skin involvement.
• Nodal Staging: ⚠️ Axillary Lymph Node Dissection (ALND) is performed. Sentinel node biopsy (SLNB) is unreliable and contraindicated.

⚡ Biggest Takeaways

• Presents as a rapidly progressive, tender, erythematous, edematous breast (peau d'orange).
• Often lacks a palpable mass and is frequently mistaken for mastitis.
• Pathophysiology involves dermal lymphatic invasion by tumor emboli.
• Diagnosis requires a full-thickness skin punch biopsy to confirm.
• Always considered locally advanced (at least T4d); carries a very poor prognosis.
• Treatment is trimodal: neoadjuvant chemotherapy, followed by mastectomy and radiation.
• Failure to improve with antibiotics is a critical diagnostic clue.