Presentation on theme: "Case Study 11 Gabrielle Yeaney, M.D.. The patient is a 23-year-old male with headaches, dizziness, anusea, vomiting, diabetes insipidus, and no seizure."— Presentation transcript:
The patient is a 23-year-old male with headaches, dizziness, anusea, vomiting, diabetes insipidus, and no seizure history. Hormone studies revealed adrenal insufficiency, hypothyroidism and low IGF-1. Describe the MRI findings (location, enhancement, etc.). Question 1
There is a cystic pineal mass (6 mm) with an enhancing solid component. The pituitary stalk (infundibulum) is enlarged. Answer
Question 2 Give a differential diagnosis based on clinical history and MRI findings.
Answer Germ cell tumor Pineo-cytoma or -blastoma Lymphoma Metastasis Rare Stuff Langerhans cell histocytosis Neurosarcoidosis Tuberculosis Infiltrative glioma Note: Pituitary adenoma and other lesions of the suprasellar variety (craniopharygioma, etc) are not likely in this scenario because of the synchronous involvement of both the stalk and the pineal gland.
Question 3 Using endoscopic endonasal approach, the contents of the pituitary stalk are identified. The surgeon notes a distinct mass within the stalk and gives you a small biopsy. Describe the cytologic features of the touch preparation. Click here to view slide.here
Answer The touch prep shows a polymorphic population of cells. There are abundant small lymphocytes and a few plasma cells. A second cell type consists of large cells each with a single round hyperchromatic nucleus with one or more macronucleoli. Mitotic figures are present. The cells on the touch prep are dyshesive.
Question 4 What is your intraoperative diagnosis? (A. Neoplastic/Defer/Non-neoplastic, B. ______)
Answer A. Neoplastic B. Poorly-differentiated neoplasm, lymphoid-rich; C. Germinoma versus lymphoma--r some variation of the above.
Question 5 What additional lab values might be ascertained from the surgeon to help with your diagnosis?
Answer Blood or CSF levels of alpha-fetoprotein (AFP), beta- human chorionic gonadotrophin or carcinoembryonic antigen if they were drawn. High levels of AFP imply the presence of yolk-sac tumor, and high levels of beta-HCG suggest choriocarcinoma.
Question 6 Review the permanent section. Describe the histologic features. Click here to view slide.here
Answer Sheets of large cells showing syncytial growth Diffuse infiltrate of chronic inflammatory cells (esp. lymphocytes) admixed with tumor cells Tumor cells are large with vacuolated cytoplasm, vesicular nuclei and prominent nucleoli Crush artifact Apoptotic and mitotic figures
Question 8 Tumor cell membranes show reactivity for c-kit (CD117) seen here. What other immunohistochemical studies might confirm your diagnosis? Click here to view slide.here
Answer Placental alkaline phosphatase (PLAP) is usually positive in germinoma but tends to be less "crisp" than c- kit. OCT4 is sensitive for seminoma, germinoma and embyronal carcinoma. Syncytiotrophoblasts are reactive for beta-HCG and cytokeratins. Syncytiotrophoblasts may be seen in germinoma in small numbers and are not necessarily indicative of choriocarcinoma.
Question 9 What classic histologic feature would lead you to a diagnosis of yolk-sac tumor (either pure or as a component of a mixed germ cell tumor)? What immunohistochemical stain is usually expressed in yolk- sac tumors?
Answer Schiller-Duval body--"endodermal sinus" that looks like a glomeruloid structure; AFP
Question 10 What immunohistochemical stain is reactive for embryonal carcinoma?
Question 11 What other imaging studies should be obtained in this patient (now or follow-up)?
Answer MRI of spine (to look for drop mets) and MRI/CT of chest/abdomen/pelvis--Metastasis outside of the CNS is rare but can occur. Abdominal cavity involvement can occur after ventriculoperitoneal shunt placement. There have been reports of CNS germ cell tumors associated with second lesions in the gonads.
Question 12 What is the prognosis and standard treatment for this neoplasm?
Answer Germinomas are often curable as they are extremely radio- and chemo-sensitive. 5-year-survival rates are 80- 96%.