Pineal germ cell tumors: Two cases with review of histopathologies and biomarkers

Abstract

Pineal germ cell tumors (GCTs) are primarily seen in pediatric and Asian populations. These tumors are divided into germinomatous and non-germinomatous GCTs (NGGCTs). GCTs are thought to arise by misplacement of totipotent stem cells en route to gonads during embryogenesis. Intracranial GCTs display an affinity to develop along the pineal-suprasellar axis and have variable manifestations dependent upon the location of the tumor. Management and outcomes are driven by histopathologies. In this study, we highlight two cases of pineal GCTs and present a review of the literature with an emphasis on histopathologies and biomarkers.

Keywords: Germ cell tumor; Germinoma; Intracranial neoplasms; Pathology; Yolk sac tumor.

Fig. 1.

(a) Histopathology of a germinoma exhibiting large cells with clear cytoplasm and round nuclei, interspersed with lymphocytes. (b) Immunohistochemical stain positive for PLAP. This figure was reproduced with the kind permission of Elsevier. J Clin Neurosci 2009 Feb;16(2):321–5.

Fig. 2.

Histopathology of a mature teratoma composed of (a) mature glial cells, (b) mucous gland cells, and (c and d) squamous epithelium at different magnifications. This figure was reproduced with the kind permission of Elsevier. Urology 2011 Sep;78(3):689–91.

Fig. 3.

(a) Histopathology of an immature teratoma composed of brain tissue (solid arrow), bone (#), and cartilage (*). (b) Separate section of the tumor exhibiting elements of immature neuroepithelium (open arrowhead), enteric-type epithelium (open arrow), and liver tissue (solid arrowhead). This figure was reproduced with the kind permission of Wiley. J Obstet Gynaecol Res 2010 Dec;36(6):1252–5.

Fig. 4.

(a) Histopathology of an embryonal carcinoma exhibiting cells with large nuclei and irregular chromatin arrangement. (b) Immunohistochemical stain positive for cytokeratins. This figure was reproduced with the kind permission of Elsevier. Am J Ophthalmol 2005 Feb;139(2):380–1.

Fig. 5.

(a) Histopathology of a yolk sac tumor demonstrating tubular and polyvesicular vitelline arrangement of cells. (b) Characteristic Schiller-Duval body composed of a vascular space inside a cystic area and lined with tumor cells. (c) Appearance of hyaline globules. This figure was reproduced with the kind permission of Elsevier. J AAPOS 2008 Dec;12(6):623–5.

Fig. 6.

(a) Histopathology of a choriocarcinoma showing the presence of both cytotrophoblastic and syncytiotrophoblastic elements. (b) Increased magnification showing mononucleate cytotrophoblastic cells. (c) Increased magnification showing multinucleate syncytiotrophoblastic giant cells. (d) Cytotrophoblastic cells lining a villous-like structure. (e) Immunohistochemical stain of syncytiotrophoblastic cells positive for hCG. This figure was reproduced with the kind permission of Elsevier. Ann Diagn Pathol 2009 Apr;13(2):96–100.