Paternity After Treatment for Testicular Germ Cell Cancer: A Danish Nationwide Population-Based Cohort Study

Oncological treatments have limited effects on the fertility prognosis in testicular cancer: A systematic review and meta-analysis

BACKGROUND

Testicular cancer is the most common solid tumour among young men in the reproductive phase. After completing cancer treatment, up to 77% of cancer survivors report an interest in paternity after completing cancer treatment. To preserve fertility, most guidelines recommend that physicians should counsel their patients about sperm cryopreservation before initiating gonadotoxic therapy. However, few studies have assessed fertility parameters after testicular cancer therapies over the last 20 years.

OBJECTIVES

To close the gap of data regarding gonadotoxicity of testicular cancer therapies to enable more accurate counselling regarding fertility preservation.

MATERIALS AND METHODS

A systematic literature search was conducted in Medline, Embase and Cochrane until December 2022. The systematic review included studies of men who had undergone all types of unilateral testicular cancer treatment, whereas the meta-analysis excluded studies with unspecified treatments, less than 10 patients for outcome evaluation or rare tumours. Infertility (i.e. azoospermia, failure to achieve paternity or the usage of cryosperm) was defined as outcome.

RESULTS

The qualitative analysis included 30 studies with a total of 13,718 men after unilateral testicular cancer. Treatment comprised active surveillance after unilateral orchidectomy (32.7%), radiotherapy (23.1%), standard- or low-dose chemotherapy (33.7%) and high-dose chemotherapy (1.4%). Post-treatment spermiograms were analysed in 17 studies. The quantitative synthesis included 23 studies, revealing an overall pooled prevalence of infertility (95% CI) of 14% (9%-21%). Azoospermia occurred in 8% (6%-12%). For good-prognosis patients who received standard therapy, the overall prevalence of infertility was only 4% (2%-10%).

CONCLUSION

So far, this very first meta-analysis of overall infertility prevalence provides the best approximation of fertility prognosis for men who have undergone testicular cancer therapy. Despite the low prevalence of infertility, it is still recommended to undergo sperm cryopreservation because of the uncertainty of the subsequent therapy and the lack of large longitudinal data on individual treatment effects.

Testicular cancer in 2023: Current status and recent progress

Testicular germ cell tumor (GCT) is the most common solid tumor in adolescent and young adult men. Progress in the management of GCT has been made in the last 50 years, with a substantial improvement in cure rates for advanced disease, from 25% in the 1970s to nearly 80%. However, relapsed or platinum-refractory disease occurs in a proportion, 20% of whom will die from disease progression. This article reviews the current evidence-based treatments for extracranial GCT, the acute and chronic toxic effects that may result, and highlights contemporary advances and progress in the field.

Fertility preservation in adult male patients with cancer: a systematic review and meta-analysis

STUDY QUESTION

Does sperm cryopreservation serve as a feasible and effective method for preserving fertility in adult male patients with cancer?

SUMMARY ANSWER

Sperm cryopreservation is an effective fertility preservation method and may benefit patients with cancer.

WHAT IS KNOWN ALREADY

Sperm cryopreservation is the only way to efficiently preserve male fertility. It is an important procedure in ART. Recently, due to remarkable advances in cancer treatment, an increasing number of studies have reported the outcomes of sperm cryopreservation in patients with cancer.

STUDY DESIGN SIZE DURATION

We conducted an extensive literature search for relevant studies published through to 31 December 2021, in the following databases: CENTRAL, CNKI, Cochrane Systematic Reviews, EMBASE, MEDLINE, PUBMED, and Web of Science. The search terms used were '(cryopreservation OR freeze OR freezing OR banking OR cryostorage OR storage) AND (sperm OR semen OR spermatozoon) AND (cancer OR tumor OR malignancy OR neoplasm)'.

PARTICIPANTS/MATERIALS SETTING METHODS

We included all studies that reported offering or attempting to cryopreserve sperm before or during cancer treatment in male patients considered at risk of treatment-related fertility impairment. We evaluated the eligibility of all data in each study. The major exclusion criteria were as follows: non-cancer patients; pediatric and adolescent cancer patients; not reporting the use of cryopreserved sperm; use of fresh semen for ART; not reporting the number of patients with cancer offered sperm cryopreservation or attempting to do so before or during treatment; using an experimental fertility preservation technique such as preservation of testicular tissue or spermatogonial stem cells; duplicate data; abstracts, case report, comments, reviews, or editorials; insufficient data reported. The quality of the included studies was assessed using the Newcastle-Ottawa scale and the Methodological Index for Non-Randomized Studies.

MAIN RESULTS AND THE ROLE OF CHANCE

This meta-analysis included 69 non-randomized studies, with 32 234 patients referred for sperm analysis and 23 178 patients cryopreserving at least one sperm sample. The pooled failed-to-cryopreserve rate was 10% (95% CI, 8-12%), and the sperm disposal and sperm use rates were 23% (95% CI, 16-30%) and 9% (95% CI, 8-10%), respectively. The pregnancy, miscarriage, and delivery rates were 28% (95% CI, 22-33%), 13% (95% CI, 10-17%), and 20% (95% CI, 15-25%), respectively. Subgroup analysis showed higher pregnancy and delivery rates, as well as a lower failed-to-cryopreserve rate, in recent studies compared to those released a decade ago. The studies from Asia reported higher sperm disposal and pregnancy rates than in other continents. Our analysis showed clinical pregnancy rates per cycle of 34% (27-41%), 24% (14-35%), and 9% (5-15%) and delivery rates per cycle of 23% (17-30%), 18% (11-26%), and 5% (1-9%) for ICSI, IVF, and IUI, respectively.

LIMITATIONS REASONS FOR CAUTION

As with all meta-analyses, some limitations should be considered. The first limitation of our study is that the data span 36 years. During this time, the World Health Organization has revised its sperm analysis standards, and other important changes have been made. There is also a limitation in that the outcome does not analyze the correlation between the type of cancer and sperm quality. Many of the earlier studies were limited by small sample sizes and a lack of control groups. Furthermore, almost all studies did not consider the severity of the disease, which could potentially have a substantial impact on the results. Consequently, further research should evaluate the effect of the type of cancer and, in particular, the severity of the condition on sperm quality in order to draw more precise conclusions. Similarly, it is inappropriate that most studies failed to differentiate between patients with different types of tumors and instead drew generalized conclusions that are presumed to apply to all patients with cancer. In the present analysis, we did not have in-depth information on patients' disease, and although extensive efforts were made to conduct a thorough systematic review and meta-analysis of the outcomes for patients with various types of tumors, the results must be acknowledged as being subject to bias. However, the use of average results obtained in each study, without the patient-level data, might also represent a source of bias.

WIDER IMPLICATIONS OF THE FINDINGS

Sperm cryopreservation is an effective fertility preservation method and may benefit patients with cancer. The observed utilization rate of frozen sperm at 9% may underestimate the actual usage, as the short follow-up period is inadequate for obtaining comprehensive data on the use of frozen sperm in young cancer survivors. ART plays an important role in fertility preservation and the achievement of pregnancy, with this meta-analysis showing that ICSI delivers better clinical outcomes than IVF or IUI in patients with cancer undergoing fertility preservation.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by the National Natural Science Foundation of China (grant no. 82001634, 81960550), and the China Postdoctoral Science Foundation (2019M661521). There are no competing interests to declare.

REGISTRATION NUMBER

CRID 42022314460.

Paternity through use of assisted reproduction technology in male adult and childhood cancer survivors: a nationwide register study

STUDY QUESTION

How does a history of cancer affect the likelihood of using assisted reproduction in order to achieve paternity?

SUMMARY ANSWER

As compared to men with no history of cancer, use of assisted reproduction to achieve paternity was more frequent in fathers with a history of cancer, mainly those with testicular, prostate, and hematological and lymphatic malignancies.

WHAT IS KNOWN ALREADY

Although it is well known that different types of cancer and their treatment may have a negative impact on fertility, there is a lack of data regarding the use of IVF and ICSI among male cancer survivors.

STUDY DESIGN, SIZE, DURATION

In this population-based nation-wide study using the Swedish Medical Birth Register, we identified all men who fathered their first-born child in Sweden between 1994 and 2014. Using personal identification numbers, anonymized data from the Swedish National Quality of Assisted Reproduction Register, Swedish Cancer Register, Swedish Multi-generation Register, and Swedish Education Register were linked with the Swedish Medical Birth Register.

PARTICIPANTS/MATERIALS, SETTING, METHODS

During the study period, a total of 1 181 488 men fathering their first-born child were identified. Of these, 26 901 fathers had a cancer diagnosis. Fathers diagnosed with cancer with <12 months from offspring conception, or with a cancer diagnosis after offspring conception, were excluded (n = 21 529). The remaining fathers who had a history of cancer (n = 5372) were divided into three groups based on age at cancer diagnosis (<15, ≥15 and <24, or ≥24 years). For subgroup analyses, they were also grouped according to the cancer location using ICD-7 codes. The fathers with no cancer diagnosis (n = 1 154 587), were included as controls. In total, 1 159 959 men were included. Associations between IVF/ICSI use and history of cancer were evaluated using logistic regression models, unadjusted and adjusted for paternal education, fathers age at childbirth, and year of conception, yielding crude and adjusted odds ratio (aOR), respectively, with a 95% CI.

MAIN RESULTS AND THE ROLE OF CHANCE

As compared to controls, childhood cancer survivors were only more likely to achieve paternity through ICSI (aOR 3.52, 95% CI 2.52-4.93; P < 0.001) but not through IVF treatment (aOR 1.02, 95% CI 0.61-1.70; P = 0.955). Similarly, teenage and young adult cancer survivors were more likely to father through ICSI treatment (aOR 6.84, 95% CI 5.64-8.30; P < 0.001) but not using IVF (aOR 1.27, 95% CI 0.90-1.80; P = 0.17). However, adult cancer survivors were more likely to conceive through either ICSI (aOR 5.52, 95% CI 4.86-6.27; P < 0.001) or IVF treatment (aOR 1.32, 95% CI 1.09-1.60; P = 0.004). In subgroup analyses, childhood survivors of testicular cancer (aOR 5.15, 95% CI 1.20-22.0; P = 0.027), soft tissue and bone cancers (aOR 4.70, 2.13-10.4; P < 0.001), hematological and lymphatic cancers (aOR 4.49, 95% CI 2.72-7.40; P < 0.001), or central nervous system (CNS) and eye cancers (aOR 2.64, 95% CI 1.23-5.67; P = 0.012), were at an increased likelihood of fathering through ICSI. Teenage and young adult survivors of testicular cancer (aOR 15.4, 95% CI 11.5-20.7; P < 0.001), hematological and lymphatic cancers (aOR 9.84, 95% CI 6.93-14.0; P < 0.001), or soft tissue and bone cancers (aOR 6.83, 95% CI 3.53-13.2; P < 0.001) were more likely to father through ICSI treatment. Adult survivors of prostate cancer (aOR 15.7, 95% CI 6.70-36.9; P < 0.001), testicular cancer (aOR 9.54, 95% CI 7.81-11.7; P < 0.001), hematological and lymphatic cancers (aOR 11.3, 95% CI 8.63-14.9; P < 0.001), digestive, respiratory, and urogenital tract cancers (aOR 2.62, 95% CI 1.75-3.92; P < 0.001), CNS and eye cancers (aOR 2.74, 95% CI 1.48-5.08; P = 0.001), or skin cancer (aOR 1.68, 95% CI 1.08-2.62; P = 0.022) were more likely to father through ICSI treatment. Only teenage and young adult survivors of hematological and lymphatic cancers (aOR 1.98, 95% CI 1.10-3.56; P = 0.022) and adult survivors of testicular cancer (aOR 1.88, 95% CI 1.37-2.58; P < 0.001) were significantly more likely to achieve fatherhood using IVF treatment.

LIMITATIONS, REASONS FOR CAUTION

Information on men failing to father children was not available, and thus our results cannot estimate the risk of infertility in men with a history of cancer.

WIDER IMPLICATIONS OF THE FINDINGS

Use of ART, in particular ICSI, was significantly more frequent in fathers with malignancies of the male reproductive tract or hematological and lymphatic systems. Our findings highlight which groups of male cancer survivors would benefit from access to fertility care, thereby improving future fertility treatment policies.

STUDY FUNDING/COMPETING INTEREST(S)

The study received funding from the Swedish Cancer Society, Swedish Childhood Cancer Society, and the Swedish Government Fund for Clinical Research. There are no competing interest.

TRIAL REGISTRATION NUMBER

N/A.