Radiological Screening and Biopsy - Mammo, MRI and/or US?

chelseasanfran

I had a suspicious mammogram last September during my annual screening and was called in for a f/u ultrasound on suspicious findings.  I had had several repeat mammograms in the past for questionable masses, as my breasts are very fibrous.  I had also complained to my PCP and gynos in the past about lumps, which they always said were just fibrous breast tissue, and discouraged me from doing regular self-exam, which was probably not such a great idea.

This time, I was told by the radiologist who did the f/u US, that it was "some kind of cancer", then had a biopsy by US, which they used for pre-op staging (said my IDC tumor was no more than 13 mm at its widest margin). They presumed me to be stage one, recommended a lumpectomy with newly approved intra-operative radiation IORT, stating that it would be just as good as WBRT, which I could avoid.  Unfortunately, my tumor turned out to be 2.4 cm, and I subsquently learned - six months post-op - that their assurances that IORT had equivalent outcomes to Whole Breast Radiation were not quite accurate, in that the procedure was so new, they only had outcomes data 5 years out and nothing beyond. 

I got lots of different recommendations for my post-op screening - MRI and/or mammogram, alternating MRI and Mammogram every six months or annually. So I went for a breast MRI at six months. The findings, which included a new 7 mm mass detected in my good breast, were incredibly vague - didn't meet basic American Academy of Radiology standards for Breast MRI interpretation - with f/u recommendation for a "second-look" US and an US guided core biopsy if there were suspicious findings on the US.

I found this very confusing. I had decided to have the breast MRI in lieu of the mammogram for two reasons. One being that it involves no radiation and two because I thought it was both more sensitive and specific.  Well, guess what, it is more sensitive - more able to detect tumors and accurately estimate their size, but not at all specific, especially for small lesions, i.e. they are very blurry with poor discrimination between benign and malignant tumors. 

So, I went back to both my surgeon and a breast radiology specialist to ask why I had an MRI if I was now being told to go backwards in sensitivity with an US for a second look and subsequent biopsy. The response I got initially was that it was "easier" and that US was what was "typically done."  But then I got feedback that breast MRI discrimination capacity - distinguishing between benign and malignant - is poor. It's also more expensive and more difficult to do an MRI-guided core biopsy (I'm not even sure how they logistically do it, but I will let you know, as I may be having one soon). This is because with Breast MRI, the woman lays on her stomach with her breasts hanging down to the floor. 

I had to insist against the US and am moving forward with another breast MRI (at another institution) and a MRI guided core biopsy if indicated by the second MRI. I think the US was a worse option, as it's less sensitive and less specific than an MRI.  Had I known more accurately the size of my tumor going into surgery last November, I would not have had IORT, as technically I wouldn't have even been eligible for the procedure. 

Now, I would rather have an unnecessary biopsy than wait another six months for a cancer to grow and if it is malignant, want to know more reliably its size for more accurate pre-op staging and decision support regarding surgery and associated treatment options. 

There is new Breast MRI technology that is much more specific, but doesn't seem available yet, except through clinical trials (and I'm not sure if there are any being conducted currently). The technique was developed by Dr. Charles Springer (Ph.D) at Oregon Health and Science University.  It was written up in a November 15th, 2010  NYT article by Denise Grady and there's a published article: Discrimination of Benign and Malignant Breast Lesions by Using Shutter-Speed Dynamic Contrast-enhanced MR Imaging Radiology November 2011 261:2 394-403. Shutter-speed analysis of breast dynamic contrast-enhanced MR imaging data was found to produce 98.6% specificity and 100% sensitivity for a cohort of 92 suspicious lesions.

I would very much like to hear from other women about their experiences and thoughts regarding these questions and issues.