What could this Large lump be???

My husband just went for a complete medical exam, and the Dr. found a large lump under his left arm, about 3-4" in diameter.  My husband swears it wasn't there the week before.  The Dr. said to see a surgeon to look at it, but that he felt for other lumps or nodes under his arms and found none.  This large lump is very soft, and almost with a squishy feel, causing no pain. It almost seems like a water balloon. My husband had just starting a new lifting routine. Could this be an injury, or something more.  All his blood work came back normal, no anemia, normal wbc and rbc counts. Thank you.

[CCF-RN,MSN-rf]

Dear cindala: This could very well be a cyst or something related to injury.  Other possiblities could be abcess (abscess) - although it might be painful and accompanied by fever and elevated WBC count.  It is best that he see a surgeon to be sure there is nothing to be concerned about.

[surgeon]

soft and squishy is almost never bad: malignancies tend to be very hard. It could be a lipoma, which is a harmless fatty tumor. The only way to know for sure is to be evaluated directly: an online answer just has no way of being accurate.