Question about sentinel node biopsy

Hi, This is my first posting.

I recently had a mastectomy and sentinel lymph node biopsy.  The pathology report states:

"Intraoperative diagnosis: Sentinel lymph node, right, biopsy: NEGATIVE for tumor (1 touch preparation)"

"Comment: Keratin AE1/AE3 immunohistochemical stains are performed on the right sentinel lymph node. They show a single cluster of keratin positive cells. This cluster measures 0.10 mm.  The intraoperative smear is reviewed and is without tumor."

My questions are:

1. How can the sentinel lymph node biopsy be Negative, while it is also stated in the pathology report "...a single cluster of keratin positive cells. This cluster measures 0.10mm." ?  What does this mean? Is the sentinel node biopsy positive or negative?

2. Just because a 0.10 mm cluster of keratin positive cells were found, is "keratin positive" = malignant/cancer cells ?

3. Should more lymph nodes have been removed during the mastectomy?

4. Is it crucial for me to go back and have more lymph nodes removed for biopsy? Or is there an alternative non-invasive approach to check other lymph nodes?

Thank you.

[lhughes]

According to my onc, they stated that anything less than 2mm is just trash and not to worry.  My positive node was just over 2mm and he stated that he "might" not have recommended the removal of the other nodes based on that one node positive.  I'm certain that having the others removed did not do me any benefit other than to prove that the cancer had not gone any further.

I would not worry so much about such a small indication.  According to my doc, that would indeed be regarded as "negative".  

Bless your heart, you won't have to deal with lymphedema, hopefully.  Good luck in the rest of your treatment, may the outcome be good.