Screen-detected lobular carcinoma in situ (LCIS) of the breast: 166 cases within the National Health Service Breast Screening Programme (NHSBSP)

Background

LCIS is classically an incidental finding on breast biopsy with no positive mammographic features. However, screening has identified a small number of cases of pure LCIS.

Aim

To review cases of screen-detected LCIS within the NHSBSP programme since its inception.

Methods

Cases of pure LCIS were identified via Quality Assurance offices and screening centres. Mammograms and pathology were reviewed and recurrence/survival data obtained. New immunohistochemistry was performed on the available pathology blocks.

Results

One hundred and sixty-six cases of screen-detected LCIS were identified in 20 centres since 1988. One hundred and seven (64%) presented with calcifications on mammography, 25 (15%) with a mass lesion and 34 (21%) with distortion or asymmetry. The preoperative diagnosis rate with core biopsy was 28/84 = 33%.

Of 106 patients in which follow-up was available to date, six went on to get an invasive cancer at a median time of 60 months; four of these were unilateral.

Conclusions

Screen-detected LCIS is a rare but important lesion. Preoperative diagnosis is difficult. Invasive recurrence is 1% per year of follow-up.