Summary
A single-centre preprint comparing 4,055 men reports earlier erectile recovery and higher potency rates after prostatectomy when surgeons used a dehydrated amniotic membrane nerve wrap. The comparison was retrospective, with the control group treated before the wrap was introduced.
A single-centre preprint reports that men who received a dehydrated human amniotic membrane (dHAM) wrap around nerves during robotic prostate cancer surgery regained erectile function sooner, on average, than men who had surgery without the wrap. The comparison included 4,055 patients, but it was retrospective and contrasted patients treated in different time periods; the findings show an association, not proof that the wrap caused the difference.
The study is posted on Research Square and has not been peer reviewed by a journal. Its authors reviewed a prospectively maintained database covering operations by one high-volume surgeon. The dHAM group included 2,560 men who underwent bilateral nerve-sparing robotic radical prostatectomy from October 2014 to October 2024. The comparison group comprised 1,495 men operated on by the same surgeon before 2014, before dHAM was used at the centre. Mean follow-up was reported as eight years.
How the wrap was used
During nerve-sparing prostatectomy, surgeons aim to preserve the neurovascular bundles alongside the prostate, which are important for erectile function. In this study, the dHAM graft was placed around those bundles after their dissection and before the surgical connection between the bladder and urethra was completed.
The researchers compared time to first erection, time to an erection sufficient for penetrative intercourse, and the proportion of patients meeting the study’s potency measure at follow-up. That measure was described as satisfactory penetrative intercourse more than half the time and a Sexual Health Inventory for Men (SHIM) score of at least 17. The paper says patients in both groups started a penile rehabilitation programme after surgery, involving daily tadalafil and on-demand sildenafil.
Recovery outcomes in the two groups
The mean time to a first erection was seven days in the dHAM group and 14 days in the comparison group. Mean time to an erection sufficient for penetration was 21 days with the wrap and 36 days without it. The authors reported statistically significant differences for both measures.
The proportion classified as potent was 75% versus 60% at three months, 87% versus 78% at six months, 98% versus 90% at 12 months, and 98% versus 94% at 24 months, comparing the dHAM and non-dHAM groups respectively. These are the study’s reported group results; the paper does not provide confidence intervals for these comparisons in the supplied text.
The researchers reported no statistically significant differences between groups in postoperative complications, surgical margin status or biochemical recurrence. Positive surgical margins were reported in 17% of the dHAM group and 20% of the comparison group. The paper also reported no cases of graft-related infection, inflammation or immune response.
Why the comparison needs cautious interpretation
The results are relevant because recovery of erectile function is an important outcome after prostate removal, and the reported differences persisted in the group comparisons through 24 months. However, this was not a randomized trial. The control patients had surgery before 2014, while the dHAM patients were treated from 2014 onward. Changes over time in surgical technique or other aspects of care could therefore contribute to differences in outcomes. The authors themselves identify the retrospective design, single-centre setting and historical comparison as limitations, and call for multicentre prospective studies.
The findings are consequently an encouraging signal about a surgical adjunct, rather than a settled estimate of its effect. The preprint’s results will need to be assessed through peer review and further prospective research before they can establish how much the wrap contributes to recovery.