Nucleosomes in pancreatic cancer patients during radiochemotherapy

Nucleosomes appear spontaneously in elevated concentrations in the
serum of patients with malignant diseases as well as during chemo-
and radiotherapy. We analyzed whether their kinetics show typical
characteristics during radiochemotherapy and enable an early
estimation of therapy efficacy. We used the Cell Death Detection
Elisaplus ( Roche Diagnostics) and investigated the course of
nucleosomes in the serum of 32 patients with a local stage of
pancreatic cancer who were treated with radiochemotherapy for
several weeks. Ten of them received postsurgical therapy, 21
received primary therapy and 1 received therapy for local relapse.
Blood was taken before the beginning of therapy, daily during the
first week, once weekly during the following weeks and at the end
of radiochemotherapy. The response to therapy was defined according
to the kinetics of CA 19-9: a decrease of CA 19-9 650% after
radiochemotherapy was considered as `remission'; an increase of
>= 100% ( which was confirmed by two following values) was
defined as `progression'. Patients with `stable disease' ranged
intermediately. Most of the examined patients showed a decrease of
the concentration of nucleosomes within 6 h after the first dose of
radiation. Afterwards, nucleosome levels increased rapidly,
reaching their maximum during the following days. Patients
receiving postsurgery, primary or relapse therapies did not show
significant differences in nucleosome values during the time of
treatment. Single nucleosome values, measured at 6, 24 and 48 h
after the application of therapy, could not discriminate
significantly between patients with no progression and those with
progression of disease. However, the area under the curve of the
first 3 days, which integrated all variables of the initial
therapeutic phase, showed a significant correlation with the
progression-free interval ( p = 0.008). Our results indicate that
the area under the curve of nucleosomes during the initial phase of
radiochemotherapy could be valuable for the early prediction of the
progression-free interval. Copyright (C) 2005 S. Karger AG, Basel.