Immature embryoid teratoma of the gall bladder: case of a primary primitive neoplasm

Abstract

This study presents diagnostic histopathological features of a primary embryoid teratomatous neoplasm in the gall bladder of a 60-year-old woman, and also discusses its pathogenesis. Sections revealed immature and typical embryoid bodies and dispersed syncytial trophoblasts along with mature and immature neuroectodermal and mesodermal elements. The residual endothelial lining of the gall bladder showed in situ and proliferative changes characteristic of an endodermal tumour. Ultrasonographic and magnetic resonance imaging findings of the rest of the abdominal and pelvic organs appeared normal. Results show that the mature adult gall bladder is susceptible to primary neoplasms of a primitive nature ranging from immature embryoma and teratoma to neuroectodermal tumour. Such primitive neoplasms in adult organs where benign neuroectodermal elements are present may evolve from a constituent cell of an adult organ acquired during embryogenesis from a morula that differentiated into trophoblastic (outer) and embryoblastic (inner) cells, and existing dormant cells at rest until reactivation during oncogenesis.

Mature cystic teratoma of gall bladder – Where do they come from?

“…4 But as reported in a case of gall bladder embryoma, which had mature as well as immature teratomatous and neuroectodermal components, the dedifferentiation of gall bladder endothelium can't explain both the presence of mature and immature components. 4 So, a second hypothesis was proposed.…”

“…PGCs) rests, which differentiates into polyclones giving rise to variants that are polyembryomatous, teratomatous (immature and mature), neuroectodermal, mesodermal, rhabdomyosarcomatous and carcinomatous (small and large blastic), and carcinoid tumours. 4 The present case of mature cystic teratoma of gall bladder can be explained on the basis of this hypothesis. The absence of surrounding organ involvement, any metastatic lymph nodes in CT scan and absence of neoplastic tissue on histopathology rules out the possibility of a metastatic origin in the present case.…”

“…1e4 This has led to the development of the following two hypotheses behind the origin of primitive neoplasms in the gall bladder. 4 The first one being that, endothelium of adult gall bladder can dedifferentiate resulting in precursor, primitive or immature neoplastic lesions. 4 But as reported in a case of gall bladder embryoma, which had mature as well as immature teratomatous and neuroectodermal components, the dedifferentiation of gall bladder endothelium can't explain both the presence of mature and immature components.…”

Mature embryoid teratoma in the wall of a mucinous cyst adenoma of ovary in multiparous female

“…In a collision tumour where the two tumours coexisted together as presently, possibility was that the teratoma originated from ovarian germ cell rest7 in the wall of the cyst adenomatous neoplasm. Another possibility could be that the mature embryoid teratoma resulted from parthenogenesis of ovum evolved in a graffian follicle which failed to rupture,8 together with the mucinous adenoma cysts by ‘epithelial metaplasia’4 of the follicular lining.…”

Collision Tumor: A Rare Case Report of Benign Teratoma and Mucinous Cystadenoma in the Same Ovary

“…Teratoma is a germ cell neoplasm whereas origin of mucinous cystadenoma is explained by metaplasia of the ovarian surface epithelium [11,17]. So in a case where these two tumours coexisted a possibility may be considered that teratoma originated from a germ cell rest [18]. Another possibility could be that the teratoma resulted from pathogenesis of ovum evolved in a graffian follicle which failed to rupture, together with the mucinous adenoma cysts from the 'epithelial metaplasia' of the follicular lining [19].…”