Invasive lobular carcinoma

Invasive lobular carcinoma
Lobules of the mammary glands.
Specialty	Oncology

Invasive lobular carcinoma (ILC) is

The histologic patterns include:[6]^[7][8]

Type	Prevalence	Description	Image
Classical	40%	Round or ovoid cells with little cytoplasm in a single-file infiltrating pattern, sometimes concentrically giving a targetoid pattern
Mixed	40%	No dominant pattern
Solid	10%	Sheets of classical-appearing cells with little intervening stroma
Alveolar	5%	Aggregates of classical-appearing cells
Tubulolobular	5%	Cells form microtubules in >90% of tumor (smaller than in tubular carcinoma)
Pleomorphic		Classical-appearing but with pleomorphic cells. It may include signet-ring cells, or plasmacytoid cells (pictured) which have abundant cytoplasm and eccentric nuclei.

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  Histopathology of invasive lobular carcinoma (ILC), next to lobular carcinoma in situ (LCIS)
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  Invasive lobular carcinoma demonstrating a predominantly lobular growth pattern
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  Lobular breast cancer. Single file cells and cell nests.
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  ILC may be subtle on low magnification (left). Higher magnification (right) shows invasive growth pattern and vesicular nuclei with prominent nucleoli.

Prognosis

Overall, the five-year survival rate of invasive lobular carcinoma was approximately 85% in 2003.^[9]

Diagnosis

On mammography, ILC shows spiculated mass with ill-defined margins that has similar or lower density than surrounding breast tissues. This happens only at 44–65% of the time. Architectural distortion on surrounding breast tissues is only seen in 10–34% of the cases. It can be reported as benign in 8–16% of the mammography cases.^[10]

Ultrasound has 68–98% sensitivity of detecting ILC. ILC shows irregular or angular mass with hypoechoic or heterogenous internal echoes, ill-defined or spiculated margins, and posterior acoustic shadowin.^[10]

Loss of