Early hematologic changes during prostate cancer radiotherapy predictive for late urinary and bowel toxicity - Abstract

BACKGROUND: The primary objective of the study was to identify early hematologic changes predictive for radiotherapy (RT)-associated genitourinary and gastrointestinal toxicity.

METHODS: In a group of 91 prostate cancer patients presenting for primary (n = 51) or postoperative (n = 40) curative RT, blood samples (blood count, acute phase proteins, and cytokines) were analyzed before (T1), three times during (T2-T4), and 6-8 weeks after (T5) radiotherapy. Before RT (baseline), on the last day (acute toxicity), a median of 2 months and 16 months (late toxicity) after RT, patients responded to a validated questionnaire (Expanded Prostate Cancer Index Composite). Acute score changes > 20 points and late changes > 10 points were considered clinically relevant.

RESULTS: Radiotherapy resulted in significant changes of hematologic parameters, with the largest effect on lymphocytes (mean decrease of 31-45 %) and significant dependence on target volume. C-reactive protein (CRP) elevation > 5 mg/l and hemoglobin level decrease ≥ 5 G/1 at T2 were found to be independently predictive for acute urinary toxicity (p < 0.01, respectively). CRP elevation was predominantly detected in primary prostate RT (p = 0.02). Early lymphocyte level elevation ≥ 0.3G/l at T2 was protective against late urinary and bowel toxicity (p = 0.02, respectively). Other significant predictive factors for late bowel toxicity were decreasing hemoglobin levels (cut-off ≥ 5 G/l) at T2 (p = 0.04); changes of TNF-α (tumor necrosis factor; p = 0.03) and ferritin levels (p = 0.02) at T5. All patients with late bowel toxicity had interleukin (IL)-6 levels < 1.5 ng/l at T2 (63 % without; p = 0.01).

CONCLUSION: Early hematologic changes during prostate cancer radiotherapy are predictive for late urinary and bowel toxicity.

Written by:
Pinkawa M, Ribbing C, Djukic V, Klotz J, Holy R, Eble MJ.   Are you the author?
Department of Radiation Oncology, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany.  


Reference: Strahlenther Onkol. 2015 May 26. Epub ahead of print.
doi: 10.1007/s00066-015-0841-3

PubMed Abstract
PMID: 26009493

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