What is the most common mammographic appearance of T1a and T1b invasive breast cancer?

Background. Data about the mammographic appearance of breast cancer smaller than 10 mm are very limited and different authors use different mammographic criteria. The aim of this study was to determine the most common mammographic appearance of small invasive breast cancers (T1a and T1b ). Patients and methods. The study group consisted of 100 women with 102 small (1-10 mm) invasive breast cancers detected on mammography at a single institution in 16 months period. The mammographic appearance of tumours was classified as: mass, mass with associated calcifications, only calcifications or others (asymmetric density and architectural distortion). Results. The most common mammographic appearance was a mass without calcifications (60/102; 59%). Additional 12/102 (11%) tumours had a mammographic appearance of a mass with associated calcifications. Only microcalcifications were detected in 12 (11 %) and asymmetric density and architectural distortion in 18 breast cancers (18 %). Most (44/60) cancers which presented mammographically as a mass had stellate margins. The proportion of castig type calcifications was higher in women under 50 years. Conclusions: The most common mammographic finding of small breast cancer is a mass with stellate margins independent of the age of patients. Calcifications with/without mass are more common in woman under 50 years.