LDH serum levels as prognostic and predictive factor in advanced biliary tract cancer patients treated with first-line chemotherapy.

313 Background: Previous data suggested that LDH serum levels may be associated with tumour hypoxia and VEGFA and VEGFR-1 over-expression. LDH may then represent an indirect marker of activated tumour neo-angiogenesis and worse prognosis in many tumour types. In our analysis, we analyzed the role of LDH serum levels in predicting clinical outcome for biliary tract cancer patients treated with first-line cisplatin and gemcitabine chemotherapy, to individuate a potentially reliable and easy to use marker for patients stratification. Methods: 71 advanced biliary tract cancer patients treated with cisplatin and gemcitabine in first-line chemotherapy were available for our analysis. For all patients, LDH values were collected within one month before treatment beginning. We chose the laboratory cut-off (Upper Normal Rate, UNR) as LDH cut-off value (450 U/l) and then we divided the patients into two groups (A and B, below and above the UNR respectively). Survival distribution was estimated by the Kaplan-Meier method. Disease control rate (DCR) was assessed with chi-square test. A significant level of 0.05 was chosen to assess the statistical significance. Results: Patients in group A (46 patients) and B (25 patients) proved homogeneous for all clinical characteristics analyzed. Median progression free survival (PFS) was 3.97 months and 1.8 months respectively in group A (patients with LDH level below the UNR) and in group B (patients with LDH level above the UNR), p=0.0064 (HR=2.07, 95%CI: 1.07-3.99). Median overall survival (OS) was 9.24 months and 2.55 months in group A and B respectively, p<0.0001 (HR=2.93; 95%CI: 1.37-6.27). DCR was 65% in group A vs. 21% in group B (p=0.004). Conclusions: Our observations seem to suggest a prognostic role of LDH in biliary tract cancer patients. Our findings showing an improved PFS and DCR in patients with low LDH serum levels also suggest a possible predictive role in patients treated with a cisplatin and gemcitabine regimen as first-line chemotherapy. After further confirmation in larger trial, these results may be relevant for a better patients stratification and selection.