S-PHASE FRACTIONS OF BREAST-CANCER PREDICT OVERALL AND POST-RELAPSE SURVIVAL

We studied the correlation of S-phase fraction (SPF) with clinical out come in 127 pre- or perimenopausal patients with breast cancers treate d by neoadjuvant chemotherapy from October 1986 to June 1990. When the patients were analysed using the median value of the SPF as a thresho ld, there was a small but non-significant difference in favour of low SPF tumours for metastasis-free survival. SPF was the only parameter p redicting overall survival in multivariate analysis (P < 0.002) which included T, N, histopathological grade and steroid hormone receptors. The results of metastasis-free survival contrasted with previous analy ses with shorter follow-up, so we tested the time-dependent influence of SPF on prognosis. It was thus shown that SPF significantly predicts metastasis-free survival only during the first 30 months, whereas the relative risk of cancer-related death according to SPF remains signif icant for 56 months. In order to find an explanation for the differenc e in predictivity between metastasis-free survival and overall surviva l, we studied the post-relapse survival. Significantly shorter surviva l (median 12 months) was associated with tumours presenting pre-treatm ent high SPF values, compared to the low SPF group for which 60% of th e patients were still alive after 30 months of metastasis phase (P = 0 .002). Our current results, in a homogeneous series with a median foll ow-up of over 5 years, emphasise the importance of proliferation-relat ed parameters for breast cancer management. (C) 1997 Elsevier Science Ltd.