title: Lactate dehydrogenase isoenzyme 1 is the most important LD isoenzyme in patients with testicular germ cell tumor.
abstract: We examined the clinical utility of serum lactate dehydrogenase (LD) isoenzyme catalytic concentrations in 58 patients with testicular germ cell tumors (TGCT) (13 with seminoma and 45 with non-seminomatous tumors). Twenty-one patients with no evidence of disease (NED) all had serum LD isoenzyme 1 catalytic concentrations (LD-1) and LD-1/LD fractions below the upper limit of the reference values (ULR). LD-1 and the LD-1/LD fraction discriminated significantly between evidence of disease (ED) and NED (p = 0.00009 and p = 0.028, respectively, Mann Whitney U-test). Twenty of the 37 patients with ED had raised values of LD-1. The 17 patients with an LD-1 < 1.0 x ULR had a better survival than the 10 patients with LD-1 between 1.0 and 2.9 x ULR, the 7 with LD-1 between 3.0 and 5.9 x ULR, and the 3 patients with LD-1 > 6.0 x ULR (p = 0.006, log-rank test, chi2 test for trend)). Twenty-three patients with an LD-1/LD fraction < or = 0.25 had a better survival than the 14 with an LD-1/LD fraction > 0.25 (p = 0.013). Nineteen patients with LD-5 < 105 U/L and the 15 with LD-5 > 105 U/L had a similar rate of survival (p = 0.85). Our findings add to the evidence showing LD-1 in preference to LD as a serum tumor marker of TGCT.
authors.affiliation: Medical Research Unit in Ringkjøbing County, Ringkøbing, Denmark.
authors.forename: F E
authors.initials: FE
authors.lastname: von Eyben
authors.forename: F J
authors.initials: FJ
authors.lastname: Liu
authors.forename: R J
authors.initials: RJ
authors.lastname: Amato
authors.forename: H A
authors.initials: HA
authors.lastname: Fritsche
mesh_terms: D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis*; D018237:Germinoma / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016019:Survival Analysis; D013736:Testicular Neoplasms / Q000201:enzymology* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D007527:Isoenzymes; D007770:L-Lactate Dehydrogenase