Noninvasive breast carcinoma: results of a national survey by the American College of Surgeons.

This study evaluates the data of noninvasive (in situ) lobular (ISLC) and ductal (ISDC) carcinoma, collected from 498 hospitals in a National Breast Cancer Survey, carried out by the American College of Surgeons in 1978. ISLC and ISDC were identified in 323 (3.2%) of 10,054 female patients with lobular and ductal carcinoma, of the total of 23,972 patients with histologically proven breast cancer surveyed (1.4%). The frequency of ISLC was significantly higher (18.5%) than ISDC (2.1%) suggesting a less agressive nature of ISLC, with a slower progression to invasion than ISDC. There was a different age distribution of ISLC and ISDC: about 80% of ISLC and 50% of ISDC were diagnosed in patients who were less than 54 years old, and the incidence showed a marked decrease in the older age groups in ISLC, whereas the incidence remained high in the following decade in ISDC. In this series there was a distinctly better five-year cure rate in the patients with ISLC (83.5%) than in the patients with ISDC (68.8%), in spite of the fact that radical surgery was performed more frequently in ISDC (67.8%) than ISLC (36.3%). The recurrence rate was five times higher (10.5%) in ISDC than in ISLC (2.5%). In black patients the recurrence rate (21.3%) was significantly higher in ISDC than in white patients (9.3%). In the present study there were no statistically significant differences in the five-year cure and recurrence rate in patients with noninvasive carcinoma, treated by more conservative procedures (72.9% and 8.5%) and those treated by more extensive surgeries (76.2% and 7.7%). The results of this study suggests that the biologic behavior of ISLC and ISDC may be different with regard to their propensity to invade and their overall prognosis. In contrast, the infiltrative form of lobular and ductal carcinoma, were found to have the same prognosis, regardless of the type of operative procedure performed.