In which I do some craaaaaazzzzy math

The HER2 was tested again, this time using FISH, which is considered to be more accurate and more conclusive. Now I know that my HER2 is negative. Supposedly this is good:

Cancer cells that are HER2 negative may grow more slowly and are less likely to recur (come back) or spread to other parts of the body (NIH).

Unfortunately, I also found this bit of info with the help of my good buddy, the internet:

Most patients with metastatic breast cancer have HER2-negative breast cancer. (ASCO)

Luckily, I took Symbolic Logic in college, so I know that “most patients with metastatic breast cancer have HER2-negative breast cancer” does NOT = “most HER2-negative breast cancer is metastatic” (just like “all girls with brown hair like ice cream” does not mean that “all girls who like ice cream have brown hair,” which seemed to be a common example in that class.) Nonetheless, I’m not liking the fact that the “m” word came up in my research on HER2-negative cancer.  But let’s carry on.

As I continue my quest to predict my staging and treatment before I meet with my doctor on July 8 (as constructive a hobby I’ve ever had), I came across information about Oncotype DX.  Knowing an Oncotype score can help predict the chance of metastasis as well as how best treat a cancer and if chemotherapy is likely to be of benefit, especially in ER+ cancers (hey, my cancer is ER+!).

I didn’t see this score mentioned in any of my pathology or imaging results, so I emailed Dr. McAuliffe to find out if the test had been done and what my score was. She replied that we would discuss this on July 8th. Figure it out myself before July 8th? Challenge accepted!

Interestingly, I found this article in which oncologists from my own hospital system, two whom I saw in 2012/13 in “Bryna takes her Breasts Off ” (not a porno) developed three ways to calculate an oncotype score without doing the actual genetic testing. It’s unclear to me why this would be preferable (my guess is cost, since it seems like not all insurance covers Oncotype testing). Of the three calculations that can be used, they say that one of them is the most accurate. It looks like this:

Magee equation 2: Recurrence score=18.8042+Nottingham score*2.34123+ERIHC*(−0.03749)+PRIHC*(−0.03065)+(0 for HER2 negative, 1.82921 for equivocal, 11.51378 for HER2 positive)+tumor size*0.04267.

I bet you’re thinking, “there’s no way a woman with four degrees in English will be able to do that equation,” especially if you’re my husband, but you would be wrong. Using my pathology reports, I figured out the corresponding information needed for each piece of the equation (Nottingham = 2; ERIHC = 260; PRIHC = 150; HER2neg = 0; Tumor Size = 2.4). I used Excel to do the math, and voila, Oncotype Dx = 9.249368. Less than 26 is considered low:

Recurrence Score of 0-15: The cancer has a low risk of recurrence. The benefits of chemotherapy likely will not outweigh the risks of side effects. (breastcancer.org)

According to the Magee researchers, when the score is very low or very high, we can expect the Oncotype score to be similar. So, if I did this math correctly, then my guess is that my Oncotype DX is on the low side.

Okey dokey, so here’s what we’re looking at in total so far:

 

Cancer Feature	Result	My assessment of what it means
Estrogen Receptor	Positive: 260	Good
Progesterone Receptor	Positive: 150	Good
HER2	Negative	Good?
Tumor Size	2+ centimeters	??
Ki-67	High, 40%	Bad
Oncotype DX score	9.2	Good
Grade	High Grade (3)	Bad
Metastasis	???	???
Lymph Node Involvement	???	???

For bonus points, I also made this table here using HTML because WordPress does not include a table maker as part of its visual text options. Come on WordPress – I’m self-diagnosing cancer here – can’t you throw me a bone with a table maker?

Final Pathology

I’ve been pathologically checking for the final pathology (haha see what I did there — oh *sigh* I’m so lame I can’t stand myself).

Anyway, as I expected, the tumor they biopsied is ER/PR+ (as was my DCIS in 2013), which is good news because ER or PR positive receptors tend to grow slower than negative ones. What this also means is that doctors will likely use hormone therapy to stop estrogen and/or progesterone from activating the cancer cells. Still, I don’t understand this part at all: I’ve managed to grow estrogen/progesterone activated cells after having my uterus and ovaries removed six years ago –  how? My research says that in postmenopausal women, androgens can be turned into small amounts of estrogen. I have a different theory – I continue to think these are the same DCIS cells from back then, before I had the hysterectomy/oophorectomy; they hung out in there mutating until they formed this lump I have now, and they’re ER/PR positive because that’s what activated them in the first place. If that’s the case, then what that also means is if someone had recommended I take Tamoxifen for several years after my mastectomy, I might not be in this situation.

Pathology also tested for HER2, and this came back “equivocal” or inconclusive. This is not great news. From what I understand, HER2 status (positive or negative) is pretty much the most important piece of the treatment puzzle. I emailed Dr. McAuliffe to ask what they’ll do about that. My understanding is that they can test for HER2 in at least two ways – an inexpensive way that shows results quickly, and an expensive way that takes longer. Since there is no description of methods in the pathology report, my hope is that they only did the first test, and they are currently working on the second test.

Because there are drugs made specifically to target HER2, it seems like it’s really important to know HER2 status:

In the era of precision medicine, human epidermal growth factor receptor 2 (HER2) is the most important predictive and prognostic biomarker in breast cancer (Gunn).

Yet, it is hard to know that status conclusively:

Inaccurate HER2 test results may cause women diagnosed with breast cancer to not get the best care possible. If all or part of a breast cancer is HER2-positive but test results classify it as HER2-negative, doctors aren’t likely to recommend anti-HER2 treatment — even though the woman could potentially benefit from [it]. If a breast cancer is HER2-negative but test results classify it as HER2-positive, doctors may recommend anti-HER2 treatment — even though the woman is unlikely to get any benefits and is exposed to the medicines’ risks. (breastcancer.org)

So, I’m glad I am having my pathology looked at by the Penn pathologists. I’m hoping that between two sets of pathologists, some clarity will be gained and I will get the correct treatment and prognosis.

Lastly, pathology showed that my rate of cell growth (Ki-67) is really high (mine is 40%; above 20% is considered high). This means that when they did the staining procedure, they could see 40% of the cancerous cells dividing to form new cancerous cells.

To sum up:

ER/PR positive = good
Ki-67 high = bad
HER2 equivocal = ??

Looks like we have a tie breaker, folks. Stay tuned.