Mydlo Jack H, Lebed Brett
Departmetn of Urology, Temple University School of Medicine, Philadelphia, PA 19140, USA.
Scand J Urol Nephrol. 2004;38(3):221-4. doi: 10.1080/00365590410025451.
Sperm banking prior to surgical procedures which may affect fertility, such as retroperitoneal lymph node dissection, has been well documented. However, such procedures are usually performed in young men. With older men marrying later in life, or remarrying, we wanted to investigate the effects of radiation on prostate cancer patients who wanted to have children afterwards.
We encountered several patients with prostate cancer who decided to undergo brachytherapy and were planning to have more children. We performed a search using PubMed and Ovid for the period 1966-2001 using the key words "fertility", "sperm banking", "radiation effects", "prostate cancer" and "brachytherapy".
Of the four young patients we encountered who underwent brachytherapy, we found no significant change in semen parameters post-therapy, and three of them were able to father a child subsequently without any deleterious side-effects. It has been demonstrated in several reports that external-beam radiation therapy is associated with decreased spermatogenesis due to Leydig cell dysfunction and decreased serum testosterone, as well as having a direct effect on spermatogonia. However, there is a scarcity of literature discussing the effects of prostate brachytherapy on spermatogenesis as the patients involved are usually older and usually do not desire to father any more children. As I has a half-life of 60 days, we used an exposure of 10 mR/h at the symphysis pubis and used integration to find the total dose exposed to the testis as follows: Limits 14 400 to 0, S 10e (-In2/1440.Tdt) where T = 14 400 and 20.75 R = 20.75 cGy. Therefore, the total dose was 20.75 cGy x 0.91 = 18.88 cGy. This value is considered too low to have any significant effect on testicular tissues.
We speculate that the effects of prostate brachytherapy on spermatogenesis in prostate cancer patients are minimal. However, due to the half-life of I, we recommend that these patients should wait for at least 3-4 months before trying to conceive. Furthermore, younger men with prostate cancer may want to consider sperm banking prior to brachytherapy if they want to have children in the future.
在可能影响生育能力的外科手术(如腹膜后淋巴结清扫术)前进行精子冻存,已有充分记录。然而,此类手术通常在年轻男性中进行。随着老年男性结婚年龄推迟或再婚,我们希望研究放疗对之后想要孩子的前列腺癌患者的影响。
我们遇到几位决定接受近距离放射治疗并计划生育更多子女的前列腺癌患者。我们使用关键词“生育能力”“精子冻存”“放射效应”“前列腺癌”和“近距离放射治疗”在1966年至2001年期间对PubMed和Ovid进行了检索。
在我们遇到的接受近距离放射治疗的4名年轻患者中,我们发现治疗后精液参数无显著变化,其中3人随后能够生育且无任何有害副作用。几份报告表明,外照射放疗与由于睾丸间质细胞功能障碍和血清睾酮降低导致的精子发生减少有关,并且对精原细胞有直接影响。然而,由于所涉及的患者通常年龄较大且通常不再希望生育,讨论前列腺近距离放射治疗对精子发生影响的文献较少。由于碘-125半衰期为60天,我们在耻骨联合处使用10毫伦琴/小时的照射剂量,并通过积分计算得出睾丸所接受的总剂量如下:范围14400至0,S = 10e^(-In2/1440.Tdt),其中T = 14400且20.75伦琴 = 20.75厘戈瑞。因此,总剂量为20.75厘戈瑞×0.91 = 18.88厘戈瑞。该值被认为过低,对睾丸组织无显著影响。
我们推测前列腺近距离放射治疗对前列腺癌患者精子发生的影响极小。然而,由于碘-125的半衰期,我们建议这些患者在尝试受孕前至少等待3 - 4个月。此外,患有前列腺癌的年轻男性如果未来想要孩子,可能希望在近距离放射治疗前考虑精子冻存。