The prognostic significance of proliferative activity in poor histology non-Hodgkin's lymphoma: a flow cytometry study using archival material.

The DNA content and proliferative activity of paraffin-embedded lymph node tissue from 111 patients with poor histology non-Hodgkin's lymphoma were measured by flow cytometry. These patients had been entered into a prospective randomized trial which, to date, has shown no survival difference by treatment arm. Forty-four (40%) samples showed evidence of aneuploidy with three samples having more than one aneuploid population. The aneuploid populations had a bimodal distribution with one group having a DNA index between 1.1-1.3 and the other 1.8-2.2. The incidence of aneuploidy did not correlate with age, stage or survival. In 56 diploid samples the S phase values below 10% had a significantly better survival than those with S phase values above 10% (P less than 0.011). For patients with diffuse large cell histology the corresponding discriminatory S phase value was 19% (P less than 0.009).