Hi Lou Lou. I know it's probably too late to give you advice you can act on, but I'm posting because I'm sure there are other women out there looking for info. I had a core biopsy last week and knew (from reading online) that it could result in a milk fistula. I lost some fluid from the incision point the first day (blood with some clear fluid and milk), but the fluid largely dried up within one day. On day 4, I started leaking milk tinged with blood. Now it's just milk pretty much. I, too, am soaking nursing pads.
I first called the breast cancer center yesterday where I had my biopsy taken. The nurse there said it was probably okay to continue to breastfeed but I should check with my OB-GYN. I then called my OB-GYN, and she said it's okay to continue breastfeeding. I wanted to find out how long this fistule would remain, so I did some online research. I've read conflicting things about healing and breastfeeding, so I used my university library to search for journal articles. I also called my lactation consultant (who said to nurse but have my OB look at it just in case). It may last as long as I continue to nurse, but it might heal sooner.
I came up with a couple of case studies, and I could only access one immediately. Being a case study, it's only one pair of doctors' opinions, and the article was written over 10 years ago:
"A milk fistula is more an annoyance than a threat. It disrupts the patient's lifestyle and could delay her return to work. A fistual can dry up spontaneously while lactation continues, but this result is not certain and closure can take several weeks [1,2]. The only reliable means of stopping a milk leak is for the woman to suppress lactation. The combination of breast binding and lack of sucking stimuli causes lactation to cease in about 1 week, but the patient may be uncomfortable because of breast engorgement . Bromocriptine [...] suppresses milk production within days without discomfort. Treatment must continue for 2 weeks to prevent relapse." from Schackmuth EM; Harlow CL; Norton LW. Milk fistula: a complication after core breast biopsy. AJR. American Journal Of Roentgenology [AJR Am J Roentgenol] 1993 Nov; Vol. 161 (5), pp. 961-2.
I also did a general Google search and a search using Google Book and found some advice that said a woman can and should keep nursing. Here's an example:
If you search Google Book, click on About this book (some current books are available, but many materials are from the late 1800s).
In addition, I found this discussion, which includes the experiences of several women: http://www.mothering.com/discussions.../t-489632.html
Ultimately, I'm going with my lactation consultant and OB-GYN's advice. If I run into problems, I'll seek further advice.