SIGNET-RING CELL VARIANT OF INVASIVE LOBULAR CARCINOMA OF THE BREAST - A CLINICOPATHOLOGICAL STUDY OF 11 CASES

In signet-ring cell carcinoma of the breast, which was recognized in 1 976 as a distinct clinicopathologic variant of lobular carcinoma, more than 20% of the malignant cells appear as signet rings formed by muci n-positive intracytoplasmic vacuoles. Several recent studies have demo nstrated that the neoplasm behaves aggressively and is associated with a poor prognosis. However, the literature lacks information concernin g steroid hormone receptor assays and DNA ploidy profiles, especially regarding how these tests affect a patient's prognosis. During a 5-yea r period (1985 to 1990), 11 (8.7%) of 126 cases of invasive lobular ca rcinoma met the criteria for signet-ring cell carcinoma. Ten of 11 cas es were positive for estrogen and progesterone receptors; six cases sh owed type I and five showed type III DNA histograms. The high incidenc e of positive hormone receptors is significant: patients with receptor positive tumors, even those with type III DNA histograms, who were tr eated with tamoxifen citrate therapy after surgery had a significant i ncrease in disease-free survival (30 months). Both the pathologist and the clinician should be aware of the prognostic influence of hormone receptor studies in the management of signet-ring cell carcinoma of th e breast.