Long-term follow-up of testicular cancer patients shows no predisposition to osteoporosis

Balancing efficacy with long-term side-effects: can we safely de-escalate therapy for germ cell tumors?

INTRODUCTION

The success in the management of germ cell tumors has encouraged researchers to pay more attention on long-term side effects and other survivorship issues. The de-escalation of treatment is intended to reduce side effects but must be balanced against any compromise of efficacy. Cisplatin-based therapy is the cornerstone of treatment for germ cell tumors. However, they can result in acute and long-term side effects, including ototoxicity, neurotoxicity, nephrotoxicity, and increased risk of second malignancies.

AREAS COVERED

This review discusses approaches of de-escalation including biomarker-directed treatment using microRNAs, surveillance for immature teratoma, the use of carboplatin monotherapy for seminoma, and the option of non-cisplatin-based approaches in relapsed germ cell tumors.

EXPERT OPINION

While the results with the current standard options in terms of cancer control are very good, the price being paid in terms of long-term side effects is considerable.

Risk of osteoporosis in testicular germ cell tumour survivors: A systematic review of the literature

Context

Testicular germ cell tumour (TGCT) survivors are potentially at risk of developing osteoporosis, because of increased risk for disturbed bone remodelling associated with hypogonadism and anti-cancer treatment. A number of studies show bone loss and increased fracture risk in TGCT survivors, but data are scarce. There are no clinical guidelines or recommendations issued to address skeletal health in this group of patients potentially at high risk for osteoporosis.

Objective

To conduct a systematic review of available literature addressing bone health in TGCT patients. Subgroup analysis was performed to identify risk factors for bone loss and increased fracture risk.

Evidence Acquisition

Relevant databases, including MEDLINE, Embase and the Cochrane Library, including all English written comparative studies addressing bone health in TGCT patients, were searched up to December 2021 and a narrative synthesis was undertaken. Risk of bias (RoB) was assessed using Cochrane ROBINS-I tool.

Evidence Synthesis

Ten studies (eight cross-sectional and two longitudinal), recruiting a total of 1997 unique TGCT patients, were identified and included in the analysis. Bone health was reported in various ways in different studies, and subgroups were defined heterogeneously, resulting in a widely varying prevalence of osteoporosis of up to 73.2% of patients. Six studies reported low BMD associated with higher luteinizing hormone levels and one study showed a correlation between follow up duration and bone loss.

Conclusions

TGCT survivors are at risk of developing osteoporosis and sustaining fragility fractures. Chemotherapy, pituitary-gonadal axis dysfunction and ageing are key risk factors, although available data are scarce. With increasing survival of TGCT patients, a clear unmet need has been identified to systematically evaluate and monitor skeletal health in larger numbers of survivors in order to develop best clinical practice guidelines to manage the insidious but potentially preventable and treatable skeletal complications of TGCT.

Association between prior cancer diagnosis and osteoporosis: a matched case-control study

Epidemiological studies show an inconsistent association between cancer and osteoporosis. In this nationally representative population-based study, we found that a prior cancer diagnosis was not associated with osteoporosis. This finding may primarily apply to cancer survivors seen many years after their cancer diagnosis.

BACKGROUND

Epidemiological studies show an inconsistent association between cancer and osteoporosis. We examined the association between a prior cancer diagnosis and osteoporosis in population-based data.

METHODS

We performed an age- and sex-matched case-control study (1:2 matching ratio) using the National Health and Nutrition Examination Survey, 2011-2018. Cases were determined by self-reported prior diagnosis of cancer; all controls were free of cancer at the time of bone density measurement with dual-energy x-ray absorptiometry. We defined osteoporosis as a T-score ≤  - 2.5 at femoral neck, total hip, or lumbar spine. Unconditional multivariable logistic regression was used to test the association between a prior cancer diagnosis and osteoporosis.

RESULTS

We identified 246 prior cancer cases and 492 controls (mean age: 65.8 years) in females, and 243 prior cancer cases and 486 controls (mean age: 68.0 years) in males. The most common types of cancer in females and males were breast cancer and prostate cancer, respectively. Osteoporosis prevalences were comparable between cases and controls among females (19.1% in cases vs. 18.7% in controls; P = 0.894) and males (5.8% in cases vs. 6.8% in controls; P = 0.594). After adjusting for covariates, a prior cancer diagnosis was not associated with osteoporosis in females (odds ratio [OR]: 0.83; 95% confidence interval [CI]: 0.54-1.29) or males (OR: 1.09; 95% CI: 0.51-2.30). Results were unaffected by cancer severity, cancer type, or time since cancer diagnosis.

CONCLUSIONS

A prior cancer diagnosis was not associated with osteoporosis in this nationally representative population.

Hypogonadism and Sexual Dysfunction in Testicular Tumor Survivors: A Systematic Review

Testicular tumor is the most common malignancy in men of reproductive age. According to the tumor histology and staging, current treatment options include orchiectomy alone or associated with adjuvant chemo- and/or radiotherapy. Although these treatments have considerably raised the percentage of survivors compared to the past, they have been identified as risk factors for testosterone deficiency and sexual dysfunction in this subgroup of men. Male hypogonadism, in turn, predisposes to the development of metabolic and cardiovascular impairment that negatively affects general health. Accordingly, longitudinal studies report a long-term risk for cardiovascular diseases after radiotherapy and/or cisplatin-based chemotherapy in testicular tumor survivors. The aim of this review was to summarize the current evidence on hypogonadism and sexual dysfunction in long-term cancer survivors, including the epidemiology of cardiovascular and metabolic disorders, to increase the awareness that serum testosterone levels, sexual function, and general health should be evaluated during the endocrinological management of these patients.

Risk of low bone mineral density in testicular germ cell cancer survivors: association with hypogonadism and treatment modality

The cure rate of testicular cancer exceeds 95%, but testicular cancer survivors (TCS) are at increased risk of hypogonadism (HG). It has been suggested that TCS have reduced bone mineral density (BMD), but it is unclear whether this is related to HG or a direct effect of cancer therapy. The aim of this study was to evaluate whether TCS have decreased BMD, and if BMD is related to HG and/or the cancer treatment given. We investigated 91 TCS (mean age at diagnosis: 31 years; mean 9.3 years follow-up) and equal number of age matched controls (mean age at inclusion 40.3 years and 41.2 years, respectively). Total testosterone and LH were measured. BMD was determined using dual-energy X-ray absorptiometry (DXA). Low BMD (LBD) was defined as Z-score <-1. Compared to eugonadal TCS, both TCS with untreated HG (mean difference: -0.063 g/cm² ; 95% CI: -0.122; -0.004 p = 0.037) and TCS receiving androgen replacement (mean difference -0.085 g/cm² ; 95% CI: -0.168; -0.003; p = 0.043) presented with statistically significantly 6-8% lower hip BMD. At the spine, L1-L4, an 8% difference reached the level of statistical significance only for those with untreated HG (mean difference: -0.097 g/cm² ; 95% CI: -0.179; -0.014; p = 0.022). TCS with untreated HG had significantly increased OR for spine L1-L4 LBD (OR = 4.1; 95% CI: 1.3; 13; p = 0.020). The associations between the treatment given and BMD were statistically non-significant, both with and without adjustment for HG. In conclusion, TCS with HG are at increased risk of impaired bone health. Prevention of osteoporosis should be considered as an important part in future follow up of these men.

Testosterone Deficiency and Bone Metabolism Damage in Testicular Cancer Survivors

The aim of the study was to investigate the influence of therapeutic modalities and sexual hormone levels on changes in bone mineral density (BMD) in testicular cancer (TC) survivors. In a cross-sectional descriptive, long-term follow-up study, a total of 1,249 long-term TC survivors were evaluated according to treatment modality: orchiectomy (OE) only, OE + chemotherapy (CT), or OE + radiotherapy (RT). Luteinizing hormone (LH), total testosterone (TST), marker of bone resorption (β-carboxyl-terminal cross-linking telopeptide of type I collagen-CTx), and BMD were evaluated. Standard statistical techniques were used to test the differences between groups of patients. TST decrease was observed in 46/313 TC survivors after OE alone, in 103/665 after OE + CT, and in 66/271 after OE + RT. LH increase was observed in 23/313 TC survivors after OE alone, in 154/665 after OE + CT, and in 43/271 after OE + RT. CTx increase was observed in 116/313 TC survivors after OE alone, in 324/665 after OE + CT, and in 82/271 after OE + RT. Osteopenia/osteoporosis occurred in 136/313 TC survivors after OE alone, in 298/665 after OE + CT, and in 139/271 after OE + RT. TC survivors after RT have statistically significant decreased TST levels, increased LH and nonsignificant worse BMD (osteopenia/osteoporosis) in comparison with TC survivors after OE alone or CT. TST decrease and LH increase were statistically significant, more frequently observed in patients with osteopenia/osteoporosis. Examination of TST is an important part of follow-up in TC survivors with bilateral as well as unilateral disease. The important part of standard examination algorithm should be also the osteological examination of TC survivors mainly in patients with androgen deficiency.

Altered bone status in unilateral testicular cancer survivors: Role of CYP2R1 and its luteinizing hormone-dependency

BACKGROUND

Recent data suggest a potential role of testis in vitamin D activation, where Leydig cells could represent key players in this process since they express the highest amount of CYP2R1, a key enzyme involved in vitamin D 25 hydroxylation.

AIM

To evaluate bone status in unilateral orchiectomy and to assess in vivo and in vitro LH-dependency of Vitamin D 25 hydroxylation.

SUBJECTS AND METHODS

125 normotestosteronemic patients with testicular cancer (TC), featured by unilateral orchiectomy and 41 age-matched healthy male controls were studied in the Center for Human Reproduction Pathology at the University of Padova. To evaluate LH-dependency of Vitamin D 25 hydroxylation in vitro, Leydig cell cultures were stimulated with hCG and assessed for CYP2R1 expression, whereas in vivo 10 hypogonadotropic hypogonadal (HH) patients were evaluated before and after treatment with gonadotropins for bone metabolism markers. Hormonal pattern and bone metabolism markers were measured in all subjects, whereas 105 patients and 41 controls underwent bone densitometry by DEXA.

RESULTS

In TC patients 25-hydroxyvitamin D levels were significantly lower compared to controls. Furthermore, 23.8% of patients with TC displayed low bone density (Z-score <-2 SD). None of the 41 control subjects showed any significant alteration of BMD. In vitro and in vivo studies revealed that CYP2R1 expression in Leydig cells appeared to be hCG dependent.

CONCLUSION

Our data show an association between TC and alteration of the bone status, despite unvaried androgen and estrogen levels, suggesting the evaluation of bone status and possible vitamin D deficiency in TC survivors.