The effect of preoperative hormonal stimulation on the urethral plate; A histologic and histochemical study

Aim of the work

Preoperative hormone stimulation (PHS) is used to increase the glans size and may improve the cosmetic appearance after hypospadias surgery. The exact effect of PHS on different penile tissues remains unclear and controversial. Previous studies showed that PHS increased vessel density in the foreskin. However, the effect of PHS on the urethral has never been studied before. In this study we examine the PHS effects on the urethral plate.

Materials and methods

Specimens of the urethral plate and the underlying tissue were excised to correct severe chordee in 16 children with proximal and perineal hypospadias with severe chordee in 2 groups. Group A consisted of 8 children received PHS prior to surgery. Group B included 8 children with proximal and perineal hypospadias with severe chordee who did not receive PHS and served as a control group. Specimens were examined blindly using hematoxylin-eosin and elastic van-Gieson stain as well as factor 8 and SMA antibodies.

Results

The median age of Group A was 13 (range 10–20) months. The median age of Group B (without prior PHS) was 17 (range 14–29) months (p = 0,03).

The median vessel-density in group A (82 vessels per mm²) was significantly higher than in Group B (65 per mm²), (p < 0.05). The median vessel diameter was also significantly higher in Group A (13 μm) than in Group B (11 μm), (p < 0.05). The median epithelial layer thickness in Group A was 110 μm and in Group B 98 μm, but showed no statistical significance (p = 0,16). There was no significant change in dartos fascia layer thickness or androgen receptor expression. There was no visual change in the organization of elastic fibers.

Conclusion

This study is the first study to document the effect of PHS on the urethral plate in hypospadias with severe chordee. PHS significantly increased the median vessel-density as well as median vessel diameter as compared to a matching control group. The findings of the study may justify PHS administration before the first operation to improve the vascularity and may reduce the severity of chordee.

1. Download: Download high-res image (991KB)
2. Download: Download full-size image

Summary figure. Histochemical findings after factor 8 staining and vessel diameter measurement. A shows a patient without PHS. B shows a patient after PHS. The increase of factor 8 and thus blood vessels is clearly visible in patient B. C&D: An area of 0,1 mm² was encircled and then mean diameter was added to 4 other circles to calculate the mean vessel diameter. C shows the same patient in A (without PHS, mean diameter size 11 μm) and D shows the patient B (after PHS, mean diameter size 13 μm).