Department of Pathology, Georgia Health Sciences University Augusta, GA.
Merkel cell carcinoma is a high-grade neuroendocrine carcinoma of skin that is characterized by immature cells which, because of its striking morphologic similarity, may be confused with other small round blue cell tumors such as pulmonary small cellcarcinoma or lymphoblastic leukemia/lymphoma. Immunohistochemistry is therefore paramount to ensuring accurate diagnostic distinction between these tumors. The aim of our study was to evaluate and compare the expression of PAX5 and Terminal deoxynucleotidyl transferase (TdT), in Merkel cell carcinoma and pulmonary small cellcarcinoma.
PAX5 and TdT immunohistochemical stains were performed on 27 Merkelcell carcinomas and 10 pulmonary smallcell carcinomas.
PAX5 was expressed in 24/27 (89%) Merkelcell carcinomas and 0/10 (0%) pulmonary small cell carcinomas. TdT was expressed in 21/27 (78%) Merkelcell carcinomas and 9/10 (90%) pulmonary small cell carcinomas.
Our study confirms that PAX5 and TdT expression can be expressed in a high percentage of Merkelcellcarcinomas and so when positive are not diagnostic of lymphoblastic leukemia/lymphoma. When dealing with metastatic lesions, PAX5 negativity would favor a diagnosis of pulmonary small cellcarcinoma over Merkel cell carcinoma. In addition, TTF-1 negative pulmonary small cellcarcinoma is to be differentiated from Merkel cell carcinoma.
Am old enough to understand the difference between the Bay of Pigs - and roasting a pig at a epicurian feast. Been thru the hippy, yippie and yuppie years - always remaining who I am.
Very much believe in "Sing your own song - weave your own tapestry"
Am young enough to still know the thrill of new discoveries, the beauty of the evening, to celebrate the joy of another tommorow.
Survived these many decades with a severe medical problems. Sorting out the maze of now having two lymphomas and all their nasty little companions, but I continue.
Besides, being a simple iconoclastic eclectic, have been called many things. An incurable romanticist - with a strong touch of reality. Thinker, intellectual (God, how I hate that term) - been told I am a lion with the heart of the poet.
Know how to wage war and conquer my foes - but would rather be known as one who brings hope and life. To bring hope into anothers life is the ultimate of joys.
Life should be about bringing hope, peace, vision... a sense of purpose beyond yourself.