Impact of tomato juice on radiation side effects and select inflammatory mediators in prostate cancer patients undergoing intensity modulated radiation therapy

This pilot study assessed tolerance of different volumes of processed tomato juice consumed daily and its impact on serum lycopene, selected serum inflammatory mediator levels and radiation-induced side effects in men with localized prostate cancer undergoing radiation therapy. Participants (n = 17) were randomized into control group or one of three intervention groups (4 oz, 8 oz or 12 oz of processed tomato juice daily). Non-Hispanic Whites comprised 71% of study participants. Tumor staging ranged from T1c-2cN0M0, with 71% of participant tumors in the T1cN0M0 stage. Participants tolerated daily tomato juice supplementation without any adverse gastrointestinal (GI) effects. Serum lycopene decreased in control group participants, while increasing from 0.33±0.11 ìg/mL (baseline) to 0.41± 0.12 ìg/mL (endpoint) in the intervention group. No correlation between serum and dietary lycopene was detected. Control group participants lost weight, while participants in the intervention groups did not. Not surprisingly, participants exhibited systemic inflammation at baseline. Overtime, increased c-reactive protein (CRP) and interleukin-6 (IL-6) was observed in control group, while decreases in serum CRP, IL-6 and prostaglandin E2 (PGE2) levels were observed in intervention groups (p>0.05). No statistically significant within group differences were detected for CRP. Within group differences were statistically significant for 12 oz group only, when comparing baseline and endpoint with midpoint levels (p = 0.014) for IL-6, and when comparing PGE2 baseline levels with midpoint and endpoint (p = 0.003). We observed no statistical correlation between inflammatory markers, cancer characteristics and dietary or serum lycopene, or acute side effects of treatment. Lower performance score was observed in intervention group participants. Daily tomato juice intake appeared to offer a GI protective effect during the first three weeks of treatment. Based on the results of this study, daily consumption of processed tomato juice (at least 8-12 oz) may decrease serum levels of CRP, IL-6 and PGE2; lower performance status score; and offer a protective GI effect during radiotherapy for prostate cancer. This information may assist in improving patient tolerance and minimize acute side-effects of radiation therapy in men with localized prostate cancer undergoing intensity modulated radiation therapy