FLOW CYTOMETRIC S-PHASE FRACTION IN SOFT-TISSUE SARCOMA - PROGNOSTIC IMPORTANCE ANALYZED IN 160 PATIENTS

We could determine the S-phase fraction (SPF) by flow cytometric DNA a nalysis of paraffin archival material in 160 of 260 patients with soft -tissue sarcoma of extremity and trunk wall. The prognostic value of S PF was compared with other clinicopathological factors. The median fol low-up time was 16 (6-31) years. In a univariate analysis, deep tumour location, increasing tumour size and histological malignancy grade, m icroscopic tumour necrosis, vascular invasion, DNA non-diploidy and hi gh SPF (>3.0%) were associated with poor metastasis-free survival. In a multivariate analysis, microscopic tumour necrosis and high SPF were independently prognostic for metastasis. Used in combination with tum our size, microscopic tumour necrosis and vascular invasion, SPF could identify a group of patients with a 5-year metastasis-free survival r ate of 0.97. This group constituted one-quarter of ail patients. Patie nts with low SPF who did recur had a prolonged clinical course both as regards metastases and local recurrence. We conclude that SPF is a va luable adjunct in prognostication in soft-tissue sarcoma.