A Case of Urachal Yolk Sac Tumor With Spontaneous Rupture in a Child

Primary yolk sac tumor in the abdominal wall in a 20-year-old woman: A case report

BACKGROUND

Extragonadal yolk sac tumors (YSTs) are rare, with only a low reported tumor occurrence outside the gonads locally and abroad. Extragonadal YSTs are usually a diagnostic challenge, because they are infrequent, but also because a thoughtful and detailed differential diagnostic process must be performed.

CASE SUMMARY

Here we present a case of an abdominal wall YST in a 20-year-old woman admitted with a tumor in the lower abdomen close to the umbilicus. The tumorectomy was performed. The histological examination revealed characteristic findings such as Schiller-Duval bodies, loose reticular structures, papillary structures, and eosinophilic globules. According to the immunohistochemical staining, the tumor tissue was positive for broad-spectrum cytokeratin, Spalt-like transcription factor 4, glypican-3, CD117, and epithelial membrane antigen. Based on the clinical information, histological features, and immunohistochemical staining profile, the tumor was diagnosed as a YST present in the abdominal wall.

CONCLUSION

Based on the clinical information, histological features, and immunohistochemical staining profile described above, the tumor was diagnosed as a primary YST in the abdominal wall.

Urachal yolk sac tumor penetrating the bladder as a diagnostic challenge: a case report and review of the literature

Background

Yolk sac tumor (YST) is a germ cell tumor. It is primarily located in the gonads but can also occur extragonadally (extragonadal yolk sac tumor - EGYST), most commonly in the pelvis, retroperitoneum or mediastinum. Only a few YSTs of the urachus have been described.

Case report

We present a rare case report of a 37-year-old male with episodes of macroscopic hematuria. The histological specimen obtained by transurethral resection showed a solid, and in some parts papillary infiltrative, high-grade tumor with numerous areas of marked nuclear atypia and clear invasion between the detrusor bundles. Glandular pattern has been observed in only minority of the tumor. Immunohistochemistry showed significant positivity for GPC3, SALL4 and cytokeratins AE1/AE3, while KRT7 and GATA3 were negative. We concluded that the biopsy findings were consistent with urothelial carcinoma with infrequent YST differentiation. In definitive surgical specimens we found a malignant epithelial, glandular and cystically arranged tumor of germinal appearance arising from urachus. The surrounding urothelium was free of invasive or in situ tumor changes. We reclassified the tumor as a urachal YST.

Conclusion

EGYST was suspected because glandular and hepatoid structures were found, but the presence of these structures should be verified by immunohistochemistry.