Can I breastfeed after breast silicone injections?

Because of your concerns, I recommend having your doctor order a test of your breast milk. It's better to have the peace of mind that it's healthy for you to breastfeed your baby. That said, do try not to worry too much: It's unlikely that the silicone injected 5 years ago (some of which appears to have spurred the formation of granulomas) will leach into the milk. Granulomas can form when the immune system responds to a foreign substance in the body — in this case, silicone — but they shouldn't pose a problem for breastfeeding. Good luck. 

The only way to know for sure if silicone is leaching into your breast milk is to have your milk tested. Any other statement on this is just conjecture. Congratulations and wishing you a smooth rest of your pregnancy and smooth delivery!

As mentioned previously the lumps are likely to be silicone granulomas. It is unlikely that any silicone will be transferred via the breast milk.