Should necrotic fat lumps be removed before building up the lower pole of my breast lost to a previous fat grafting? (Photos)

Thank you for this question and I'm sorry you experienced this.  I would not recommend removal of the fat necrosis lumps for many reasons. 1) Depending on how recently they occurred, they can change and soften over time; 2) Removing those areas will cause more trauma to the tissue and potentially cause more areas of fat necrosis.  That would be a never-ending cycle and you would continue to lose breast volume and increase in scar tissue with more breast deformity.
It is appropriate to do fat grafting without removal of the areas of fat necrosis.  Timing would be the biggest factor.  The longer you wait (up to 1 year), the better idea you'll get about how the areas of fat necrosis are going to settle and how the breast will appear. This will help assist in better placement of fat graft to improve the contour and aesthetics of the breast.  Be sure to discuss the with you surgeon.  All the best!

Thank you for submitting your concerns.Based on the photographs and your concerns you would be a good candidate for Breast reconstruction. The removal of the lumps would be the first step you want take, followed by fat grafting where necessary. I would recommend you consult with a Board-certified plastic surgeon for the best results because it is too specific to inform on what procedure you may benefit from specifically just with your photographs. Best of luck. 

Fat necrosis after grafting is a well-known issue and can be worse depending on technique. Your situation does seem severe. I generally recommend removing the nodules before any further fat grafting or reconstruction. Reasons to do so include pain, masses mimicking cancer, poor cosmetics, skin retraction, and so on. Keep in mind that by removing you will likely be creating soft tissue voids and contour irregularities. Also, it may take multiple corrective surgeries to accomplish a stable soft tissue envelope. I feel your pictures warrant correction, in my opinion.I adopted fat grafting very early and was part of several trials a decade ago. I perform fat transfer in over 50% of my reconstruction cases. I find it to be a tremendous tool for reconstruction but you have to respect its limits. Visit with your surgeon and discuss your concerns. Assuming their experience is adequate, they will understand the problem and prescribe the correct course of action.Best wishes. Dr. Spann