Case Number : Case 2779 - 2 March 2021 Posted By: Uma Sundram

Not enough images, or too difficult case for me. ? Sebaceous Carcinoma. 

Difficult for me too. But let´s try: What about a Trichilemmal Carcinoma?

Squamous cell carcinoma with clear cell change

3 hours ago, Anil Patki said:

Squamous cell carcinoma with clear cell change

Yes, that's my impression too.

Agree with clear cell squamous cell carcinoma, but why is neither a Sebaceous Carcinoma nor Trichilemmal Carcinoma to me?
Well, in SC the cells have microvacuolated cytoplasm and central nuclei, irregular, spiculates and kind of scallopated with a lot of mitotic figures and even necrosis;  TC is well difenid with periferall palisaded, lobulated, there is more atypical squamoid cells, bright eosinofilic citoplasm with clear cell changes as well, the nuclear atypia is moderate to severe, mitotic figures incresed a few of them atypical and of course... trichilemmal like keratinization

Clear cell SCC. I thought the type and amount of clear cell change was striking. I will ask Trevor about the images. They have a lot of compression artefact.

20 hours ago, Victor Delgado said:

Agree with clear cell squamous cell carcinoma, but why is neither a Sebaceous Carcinoma nor Trichilemmal Carcinoma to me?
Well, in SC the cells have microvacuolated cytoplasm and central nuclei, irregular, spiculates and kind of scallopated with a lot of mitotic figures and even necrosis;  TC is well difenid with periferall palisaded, lobulated, there is more atypical squamoid cells, bright eosinofilic citoplasm with clear cell changes as well, the nuclear atypia is moderate to severe, mitotic figures incresed a few of them atypical and of course... trichilemmal like keratinization

Yes. Well done. And useful description about differential. Thanks Victor. 

On 03/03/2021 at 20:19, Victor Delgado said:

Agree with clear cell squamous cell carcinoma, but why is neither a Sebaceous Carcinoma nor Trichilemmal Carcinoma to me?
Well, in SC the cells have microvacuolated cytoplasm and central nuclei, irregular, spiculates and kind of scallopated with a lot of mitotic figures and even necrosis;  TC is well difenid with periferall palisaded, lobulated, there is more atypical squamoid cells, bright eosinofilic citoplasm with clear cell changes as well, the nuclear atypia is moderate to severe, mitotic figures incresed a few of them atypical and of course... trichilemmal like keratinization

Agree