Biopsy results- please clarify

I had mentioned earlier that I had a lump in my right underarm for 4-5 years and got a needle biopsy done 3 weeks back. My surgeon then said that he was 99% sure it was lipomas and yesterday he tells me that report says abnormal cells were present and the pathologist requires more sample. He suggests that I go for complete removal to be safe.When he did biopsy I saw straw coloured liquid and 1-2 small colourless tissue. The main problem is I am 11 weeks pregnant with my first child . He says that the operation can be done via local anesthesia.
1)I want to know whether and when its safe.??Can I push the operation after delivery?
I am extremely stressed out with my existing pregnancy symptoms and dont want harm to my baby.
2)Another important question is whether this atypical cells mean I have some kind of cancer or could it be malignant..
I am surprised as I have led a healthy life with the lump so far.
3)Want kind of results can I expect with the surgical biopsy. I am 26 years old. Thanks for answering this question. I really appreciate it.

[CCF-RN,MSN-JS]

Dear Annautum, Based on the needle biopsy results there is not enough information to say this lump is normal and no problem since the atypical or abnormal cells were present.  There might be abnormality that is just that - some abnormal cells, or a pre-cancer, or a possibility of malignancy (cancer), thus the recommendation of removal to make sure.  After the first trimester of pregnancy the babies organs are formed so it is less of a risk to proceed with the removal of the lump at that time, especially if it is done under local anesthetic.  Then based on those results would further recommendations be made, taking into account the pregnancy.

[surgeon]

atypical doesn't mean cancer, especially on a needle biopsy. It might be ectopic breast tissue, not all that rare to be found under the arm, which is responding to the hormones of pregnancy. Removing the lump, or sampling it more widely is very safe for the baby when done under local anesthesia. At your age the odds are huge that it will turn out to be no big deal. The problem with waiting til the birth is that on the way outside chance that it's serious a lot of time will pass before treatment. Local is safe.