Endocrine Abstracts

Introduction: Testicular cancer (TC) is the most common cancer in white males aged 20–40 years, with a worldwide incidence of 7.5/100.000. Recently, we demonstrated an association between testiculopathy and alteration of the bone status, despite conserved bone-sparing effects of androgens and estrogens. Furthermore, recent published data from our group documented a strong reduction in 25(OH)D plasma levels in bilaterally orchiectomized patients compensated by testosterone-replacement therapy. These data suggested a potential role of testis in vitamin D activation. In fact, we demonstrated that the Leydig cell represents a main actor in this process expressing a high amount of CYP2R1, a key enzyme involved in vitamin D 25-hydroxylation. Few reports have investigated the incidence and pathogenesis of altered bone status in subjects with TC and the available literature shows contrasting data.

Materials and methods: One hundred and twenty five patients orchiectomized for unilateral TC, followed up over a 2-year period, and 41 age-matched healthy male controls were enrolled. Serum levels of total testosterone, oestradiol, LH, FSH, PTH, 25(OH)D, 1,25-(OH)2D, bone-specific alkaline phosphatase (BAP), and carboxyl-terminal telopeptide of collagen type I (ICPT) were measured in all subjects. Eighty-four patients and 41 controls underwent bone densitometry analysis by DEXA.

Results: 25-(OH)D levels were significantly lower and PTH, BAP and ICTP levels higher in TC patients compared to controls (P<0.05). Femoral neck and/or lumbar spine T-score was <−1 S.D. (osteopenia) in 30/84 TC subjects (35.7%) and <−2.5 S.D. (osteoporosis) in 8/84 TC subjects (9.5%). None of 41 control subjects showed alterations of BMD.

Conclusions: Our data show an association in patients orchiectomized for unilateral TC and alteration of the bone status, despite unvaried androgen and oestrogen levels and no other evident cause of vitamin D reduction.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.