Thank Dr. Zhang's good differential dx.  When we see these kinds of lesions we must consider the differential dx. Three ddx including Paget's, Bowen, and melanoma should  be in our mind immediately. The treatment and prognosis of these diseases can be huge different. We always do some stains for these lesions even though we can favor some dx based on H@E. You can be right in most of the time, but you will be wrong some time during your life long practice.  

 Hope some of you can write your differential diagnosis and immunostains needed briefly. Thank, cz

 Good to see above diagnosis. What will you do about this  case If it is your case in clinical practice? As pathologists we cannot guess diagnosis even though we might be right in most of the times. We should have our differential dx even for some easy-looking cases.

Can you sleep well if you sign out the case without any other study?

以下是引用wangxuanju在2009-8-13 21:48:00的发言：  考虑是Paget's ，但是光就这个区域不能确诊，最好还是多发几张图片吧！

This is biopsy specimen. Is there size criteria for diagnosis of Paget's?

 Another photo based on  your requirement