A 45 year old man with a history of renal transplant presented with lymphadenopathy. A lymph node biopsy was performed. A representative image is shown. The large atypical cells are positive for CD30 and CD15 with dim PAX5 nuclear positivity and dim and variable CD20 expression. CD3 and CD45 are negative. Which of the following is the most appropriate diagnosis?
Select an answer:
A. Classic Hodgkin lymphoma posttransplant lymphoproliferative disorder
B. Monomorphic posttransplant lymphoproliferative disorder (diffuse large B cell lymphoma)
C. Nondestructive posttransplant lymphoproliferative disorder (florid follicular hyperplasia)
D. Polymorphic posttransplant lymphoproliferative disorder
An 80 year old Caucasian woman had a thyroid mass and a 1 cm pulmonary lesion. CT guided transthoracic needle biopsy was performed to rule out metastatic tumor. Microscopic examination of core needle biopsy tissue reveals the following lesion. What is your diagnosis?
The cellular population within the nodules shows spectrum of differentiation, comprising of stellate to spindle mesenchymal cells in a myxoid background at one end, as seen in this example, to well developed hyaline cartilaginous differentiation on the other end.
Site: pancreatic head. Procedure: Whipple resection. Diagnosis: medullary pancreatic ductal adenocarcinoma. Histologic finding: neoplastic cells with syncytial growth and without gland formation (hematoxylin eosin, original magnification 10x). Molecular findings: microsatellite instability is very common in the case of medullary histology.