Invasive lobular carcinoma of the breast: should this be regarded as a chronic disease?

The surgical treatment of patients with invasive lobular carcinoma is still controversial due to its different clinical and pathological features. Most studies report local recurrence after relatively short follow-up periods, which is usually 5 years. However there is some evidence to suggest that local recurrence may occur late in the course of follow-up.

To study the implications and outcome of extending the follow-up period of patients treated for invasive lobular carcinoma.

Patients (268) treated between 1989 and 1996 were reviewed. Thirty-three patients were excluded as they had primary hormonal therapy. The outcomes for 235 patients were analyzed.

Seventy-nine patients (33.6%) had breast conservation surgery (group I), which was followed by re-excision due to positive margins in 23 patients (29%), and 156 patients (66.3%) had mastectomy (group II). Compared to group II, tumours in group I were smaller (mean size 17 vs. 37 mm, P=0.001), multifocal [20 (25%) vs. 14 (9%), P=0.003] and with more positive margins [23 (29%) vs. 24 (15%), P=0.0009]. Only 33 patients (21%) in group II, and all patients in group I had post-operative radiotherapy (P=0.0001). Forty-eight patients (17.9%) developed local recurrence [27 (34%) in group I and 21 (13.4%) in group II, P=0.0005] after a median follow-up period of 167.8 months. The mean time to local recurrence was 127 (range 24-196) months. Univariate analysis showed that the type of surgery, margin status, adjuvant radiotherapy and chemotherapy significantly affected local recurrence (P=0.0005, 0.02, 0.04 and 0.05 respectively). Cox regression analysis showed that the only factor affected local recurrence was the type of surgery (relative risk 2.43, 95% confidence interval 1.22-4.83, P=0.01) The overall survival was 99.3 months (78.2%). Univariate and Cox regression analyses showed that only the patients age at diagnosis significantly affected survival (P=0.003).

Local recurrence may be a late event in patients treated for invasive lobular carcinoma of the breast and extended follow-up may be considered. In this study mastectomy offers better local control.