yolk sac

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Related to Yolk sac tumor: embryonal carcinoma

yolk sac

n.
A membranous sac attached to the embryo and enclosing the yolk in egg-laying vertebrates. In humans and other placental mammals, it functions as the circulatory system for the embryo before internal circulation begins.

yolk sac

n
1. (Zoology) the membranous sac that is attached to the ventral surface of the embryos of birds, reptiles, and some fishes and contains yolk
2. (Zoology) the corresponding part in the embryo of mammals, which contains no yolk

yolk′ sac`


n.
an extraembryonic membrane that encloses the yolk of eggs.
[1860–65]

yolk sac

A sac attached to the gut of an embryo that encloses the yolk in bony fish, sharks, reptiles, mammals, and birds. In most mammals, the yolk sac functions as part of the embryo's circulatory system before the placenta develops.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.yolk sac - membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functionalyolk sac - membranous structure that functions as the circulatory system in mammalian embryos until the heart becomes functional
sac - a structure resembling a bag in an animal
2.yolk sac - membranous structure enclosing the yolk of eggs in birds, reptiles, marsupials, and some fishes; circulates nutrients to the developing embryo
sac - a structure resembling a bag in an animal
References in periodicals archive ?
Seminoma with tubular, microcystic, and related patterns: a study of 28 cases of unusual morphologic variants that often cause confusion with yolk sac tumor.
Primary yolk sac tumor of endometrium: Report of two cases and review of literature.
The use of cytokeratin 7 and EMA in differentiating ovarian yolk sac tumors from endometrioid and clear cell carcinomas.
The most common type of testicular tumors in children is yolk sac tumor (54-66%).
Successful orthotopic liver transplantation for treatment ofa hepatic yolk sac tumor.
Incidence of pediatric testicular tumors according to Prepubertal Testis Tumor Registry data (11) Tumor type No of patients Percent (%) Germ cell tumors Yolk sac tumor 244 62 Teratoma 92 23 Epidermoid cyst 13 3 Stromal tumors Juvenile granulosa cell 11 3 Sertoli's cell 10 3 Leydig cell 5 1 Non-specified 16 4 Gonadoblastoma 4 1
Immunohistochemically, different expression patterns were noted in various subtypes of GCTs, like seminoma, embryonal carcinoma, yolk sac tumor, teratoma and choriocarcinoma, in primary and metastatic lesions.
Postoperative paraffin pathology found a mixed germ cell tumor (GCT) composed of immature teratoma, dysgerminoma [Figure 1], and yolk sac tumor [Figure 2] in right ovary while a mixed tumor composed of GCT and sex cord stromal tumor (mature teratoma and gonadoblastoma) was identified in left ovary.
The differential diagnosis includes juvenile granulosa cell tumor (JGCT), yolk sac tumor, cystic teratoma, Sertoli cell tumor, and Leydig cell tumor.
One solitary case of yolk sac tumor was found in a 20-year-old patient.
The diagnosis and treatment of yolk sac tumor in infants and children.