In one of my classes last year, I heard a cancer specialist discuss breasts, breastfeeding and lumps. One of the biggest questions that I have always had was how to know which lumps are "normal" during lactation and which ones should be worried about. While I will never be casual with any mother regarding persistent lumps, he did share some guidelines that I found to be very helpful and reassuring: In palpating the lump, check the symmetry, the roundness, the rootedness. Is it fairly round, or is it irregular in shape? Is it symmetrical, or oddly shaped? Does it move as you probe, or does it seem "rooted" and unyielding to the touch? Cancerous lumps are most often irregular, unsmooth, and very rooted to the breast, whereas benign lumps are smooth, more round in shape, and will "float" or move as you explore them. I keep these guidelines in my mind when I take calls or check out the occasional lump. Most of the time it is a plugged duct, and I give the usual instructions on how to clear it. But I do always ask the mothers to call me back if it doesn't clear up, and refer them to their ob-gyn when there is a question here. -Lisa Lisa A. Marasco, IBCLC International Board Certified Lactation Consultant [log in to unmask] [log in to unmask]