[Ultrasonographic and clinical features of common testicular germ cell tumors in children].

OBJECTIVE: To study the ultrasonographic manifestations and clinical features of common pediatric testicular germ cell tumors (TGCT) in children. METHODS: We retrospectively analyzed the laboratory, ultrasonographic and clinical data on 92 children with TGCT diagnosed in Shanghai Children's Hospital from March 2013 to January 2019, and investigated the values of the serum alpha-fetoprotein (AFP) level and maximum diameter of tumors in the diagnosis of benign and malignant tumors using the ROC curve. RESULTS: Of the 92 cases of pediatric TGCT, 64 (69.6%) were pathologically confirmed as benign tumors, including 40 cases of teratoma (62.5%), 18 cases of epidermoid cyst (28.1%) and 6 cases of dermoid cyst (9.4%), and the other 28 (30.4%) as malignant neoplasms, including 26 cases of yolk sac tumor (YST, 92.9%) and 2 cases of mixed germ cell tumor (MGCT, 7.1%). Ultrasonography showed that 62.5% of the teratomas were cystic-solid mixed (25/40) and 32.5% solid masses (12/40), that 33.3% of the epidermoid cysts exhibited a typical sign of "onion ring" (6/18) and 22.2% that of capsular calcification (4/18), and that 42.3% of the YSTs displayed isoechoic (11/26), 30.9% hypoechoic (8/26) solid masses without calcium and 26.9% cystic anechoic lesions (7/26). Color Doppler blood flow imaging manifested abundant blood flow signals in most of the YSTs (25/26, 96.2%) but none in either the epidermoid or the dermoid cysts. The area under the ROC curve (AUC) of the serum AFP value was 0.985, with an optimal cutoff value of 124.2 ng/ml, and the sensitivity and specificity of AFP in the diagnosis of benign and malignant tumors were 92.9% and 93.7%, respectively. The AUC of the maximum diameter of the tumors was 0.796, with an optimal cutoff value of 2.7 cm, and the sensitivity and specificity of the maximum diameter of the tumors in the diagnosis of benign and malignant neoplasms were 57.1% and 93.7%, respectively. CONCLUSIONS: Ultrasonographic images have different characteristic manifestations for different pathological types of pediatric TGCT. Pediatric TGCT has a good prognosis and radical orchiectomy should be considered for the treatment of the tumors with serum AFP ≥ 124.2 ng/ml and a diameter ≥ 2.7 cm.

[High-frequency ultrasonography for diagnosis and differential diagnosis of acute scrotum in children].

OBJECTIVE: To analyze the high-frequency ultrasound image features of acute scrotum in children and explore the value of high-frequency ultrasonography in the diagnosis and differential diagnosis of the disease. METHODS: This retrospective study included 256 children aged 2 days to 14 years undergoing color Doppler ultrasonography at 2 hours to 3 days after onset of acute scrotum. We analyzed the morphology, internal echo and blood supply of the testis in comparison with the clinical and pathological results. RESULTS: Among the 256 cases, acute testicular torsion was found in 23, of which 16 were treated by complete resection the necrotic testis and the other 7 by surgical reduction of testicular torsion. Ultrasonographically, the involved testes presented different degrees of increase or decrease in volume, with uneven internal echoes, irregular hypoechoic flakes, and testicular hydrocele. Color Doppler flow imaging (CDFI) showed significant blood flow signals around the diseased testes but none within them. Acute testicular appendix torsion was found in 116 cases, in which ultrasonography manifested nodules with round or oval abnormal echoes between the upper pole of the testis and caput epididymidis, first hypoechoic and then gradually increased, heterogeneous internally. CDFI revealed enlarged epididymides and enriched testicular blood flow but no blood flow signals in the nodules. The 103 cases of acute epididymitis were ultrasonographically characterized by varied degrees of swelling of the involved epididymis with uneven internal echoes and rich blood flow signals on CDFI. Six of the cases were diagnosed as acute orchitis, with the ultrasonographic features of testicular swelling and low but uniform internal echoes, with rich blood flow signals on CDFI. Incarcerated inguinal hernia was confirmed in 15 cases, in which ultrasonography revealed intrusion of the hernia into the obviously enlarged scrotal sac with the mesentery and intestine in it, and blood flow visible on CDFI. Acute scrotal wall hematoma and edema was found in 8 cases, with the ultrasonographic characteristics of scrotal wall thickening, with visible blood flow signals on CDFI. CONCLUSIONS: High-frequency ultrasonography has a high sensitivity and specificity for acute scrotum in children, which can be applied as the first-choice clinical imaging modality and provide reliable evidence for the diagnosis and differential diagnosis of the disease.