The Contralateral Testis Hypertrophy And Assessment Of Ipsilateral Testicular Status In The Unilateral Nonpalpable Testes

Objectives:1. To investigate the incidence of contralateral testicular hypertrophy(CTH) in boys with a nonpalpable testis (NPT) and the relation betweenCTH and the status of NPT and the age of the boys.2. To evaluate the accuracy of assessing the ipsilateral testicular statusfrom the size of the contralateral descended testis (CDT).Methods: From January2009to December2012, we evaluated148patients with unilateral NPT from1,465children with cryptorchidism at ourinstitution. The nonpalpable status of the side was confirmed by physicalexamination, preoperative ultrasonic examination was performed to locatethe NPT and measure the testicular volume, all of them had a laparoscopicor inguinal exploration. The age of these148patients varied from8monthsto12.4years at surgery, including79boys in0～3years,23boys in3～5years,35boys in5～10years and11boys in10～13years. Base on thestatus of the NPT in surgery, we divided all cases into atrophic and absenttestes group (104testes), intra-abdominal testes group (21testes) andinguinal testes group (23testes). We also recorded the testicular sizes with ultrasonography in300age-matched healthy volunteers with no testicular orsystematic abnormalities as controls. We compared the contralateraltesticular size with those of300age-matched normal boys at different agesand defined contralateral testicular volume increased by15%～25%,25%～35%,35%～45%and≥45%relative to the age-matched normal boysas light, moderate, severe and extreme hypertrophy.Results:1. The volume of testis was increasing with ages. The mean volumesof the CDT in boys with a NPT were larger than those of controls duringbirth to10years, and the differences were significant from birth throughyear5(P＜0.05). It revealed that CTH was common in boys with a NPTand it was influenced by ages.2. The incidence of CTH in boys with a NPT. Comparing the volumesof CDT in148patients with the mean size of the even-aged normal boys,we found88(59.5%) boys with a contralateral testicular volume was15%or more larger than controls, including11(7.5%） boys with lighthypertrophy,12(8.1%) boys with moderate hypertrophy,20(13.5%) boyswith severe hypertrophy and45(30.4%) boys with extreme hypertrophy,respectively.3. The relation between CTH and the age of the boys. The proportionof the CDT with15%or more greater volume than age matched controlswas72.2%,47.8%,51.4%and18.2%in0～3years,3～5years,5～10 years and10～13years groups, respectively. Whereas, the proportion ofthe CDT with least35%greater volume than controls in the age groups was49.4%、47.8%、37.1%and18.2%, respectively. Spearman analysisindicated CTH had a negative correlation with the ages (ρs=-0.296, P=0.00026). It suggested that CTH seemed to be more frequent andpronounced in early prepuberty.4. The relation between CTH and the status of NPT. There were76(73.1%) boys with CTH in104atrophic and absent testes,7(33.3%) boyswith CTH in21intra-abdominal testes and5(21.7%) boys with CTH in21inguinal testes. Furthermore, the proportion of atrophic and absent testeswas81.8%,83.4%,85.0%and88.9%in boys with a light, moderate, severeand extreme hypertrophic testis, respectively. There was a significantdifferences between atrophic and absent testes group and control during0～7years (P＜0.05), but not between intra-abdominal testes and inguinaltestes group and control (P＞0.05). It revealed that CTH mainly occurred inboys with atrophic and absent testes, and the more pronounced ofhypertrophy, the more likely to be absent or severe atrophy for the NPT.5. The assessment of ipsilateral testicular status from CTH. ROC curveanalysis indicated CTH (cutoff at0.1464≈15%; AUC:0.784;95%CI:0.700～0.869) was a useful predictor of atrophic and absent testes inunilateral NPT. The optimal cutoff value for predicting absent testis is thevolume of the CDT increases at least15%relative to the age-matched normal boys with a positive predictive value and negative predictive valueof86.4%and53.3%.6. The assessment of ipsilateral testicular status from ultrasonography.Preoperative ultrasound correctly identified22of the23inguinal testes(95.7%sensitivity),10of the21intra-abdominal testes (47.6%sensitivity),and92(88.5%) boys had atrophic and absent testes of the104patients withnegative ultrasound.7. When we excluded23patients with inguinal testes, there were76(91.6%) boys had atrophic and absent testes in83cases with CTH. Of the72patients with both negative ultrasound and CTH,67(93.1%) boys hadatrophic and absent testes.Conclusions:1. CTH is common in patients with a NPT and the incidence is about59.5%. The hypertrophy mainly occurs in boys with atrophic and absenttestes and it seems to be more frequent and pronounced in earlierprepuberty.2. CTH is a useful predictor of atrophic and absent testes in unilateralNPT. The optimal cutoff value for predicting atrophic and absent testes isthe volume of the CDT increases at least15%relative to the age-matchednormal boys. The more pronounced of hypertrophy, the more likely to beatrophy and absent for the NPT. The probability of atrophy and absence forNPT is81.8%,83.4%,85.0%and88.9%in boys with a light, moderate, severe and extreme hypertrophic testis, respectively.3. Although ultrasound is not reliable for truly intra-abdominal testes,it may reliably identify NPT in the inguinal canal. If the patients withnegative ultrasound, it predict the testis atrophic and absent with anaccuracy of about88.5%.4. It will increase the accuracy of predicting the absence or presence ofNPT from CTH combining with the result of ultrasonography and acarefully physical examination to rule out a palpable testis, which wouldprovide more valuable information for preoperative counseling andtreatment planning for the patients with a NPT.