WHY breast cancer treatment can never be "one size fits all"

[Lani]

I often seem to rattle on regarding why it is important to look at breast cancer subtypes, comparing breast cancer to a fruit salad where one should not compare apples, oranges, pineapple, guavas and passionfruits (now was;t that delicious!)

Here is a perfect example of the need not only for individual treatment of tumors, but of different treatment of two tumors which developed simultaneously in the same patient.

Mol Cancer Ther. 2012 Aug 9. [Epub ahead of print]
Discordant cellular response to pre-surgical letrozole in bilateral synchronous ER+ breast cancers with a KRAS mutation or FGFR1 gene amplification.
Balko JM, Mayer IA, Sanders ME, Miller TW, Kuba MG, Meszoely IM, Wagle N, Garraway LA, Arteaga CL.
Source
1Medicine, Vanderbilt University.
Abstract
We describe herein a patient presenting with bilateral ER+ breast tumors. The patient was enrolled in a clinical trial exploring molecular aberrations associated with hormone-refractory tumor cell proliferation. Short-term (2-week) hormonal therapy with the aromatase inhibitor letrozole substantially reduced proliferation as measured by Ki67 immunohistochemistry in one tumor, while the second was essentially unchanged. Extensive molecular and genetic workup of the two tumors yielded divergent lesions in the two tumors: an activating KRAS mutation in the responsive tumor, and an amplification of the FGFR1 locus in the treatment-refractory tumor. These findings provide an insight to possible mechanisms of resistance to antiestrogen therapy in ER+ breast cancers. First, they illustrate the necessity of clinically approved assays to identify FGFR1 gene amplification, which occur in ~5% of breast tumors and have been linked to antiestrogen resistance. It is quite possible that the addition of FGFR inhibitors to ER-targeted therapy will yield a superior antitumor effect and improved patient outcome. Second, they suggest that the role of activating mutations in RAS, although rare in breast cancer, may need to be explored in the context of ER+ breast tumors.
PMID: 22879364

['lizbeth]

Thank you Lani. I'm please to see this information. I was multi focal in the right breast and asked if there was any difference in the lesions by the nipple, which were only detected by MRI, and the the larger lesion located above. Five years ago, that question was a bit ahead of the medical communities way of thinking. Now so many changes are bringing more tools to the treatment of cancer.

I'm so glad you are great at discovering this information and sharing it with us.

[Laurel]

Like the salad metaphor, Lani. This is interesting, but do you think extensive molecular and genetic testing on all tumors will ever become the norm due to the associated expense? Much of this lab work currently runs in the 3-5k price range and that is just for the standard ki67. It would be wonderful to have the knowledge, but just as with our propensity to mets to the CNS where routine MRI screening is suggested, the expense vs benefit becomes the prevailing limitation.

[Lani]

sequencing the human genome used to cost multimillions of dollars. I have read (U think in the Economist) that we are now probably less than a year away from the cost being #1000 and it will continue to drop. Where there is a will, and a money-generating contest competing aginst for profit large companies trying to maximize profiti ( companies should realize there is more money to be made making the test affordable, making up in quantity sold for the lower price --thank you Henry Ford and the Model T for showing the way!)

MIcrofluidic chips may lead the way and I am sure other methods including spectroscopy (noninvasive, not even a blood test) could be developed further.

If one only looks at what things cost now, one will stay in the mode of why test for mets early if the person will ony die in two years one way or the other.

If we don't try, we won't get better at fighting breat cancer and other cancers.

Off the soap box again.

[Laurel]

I agree, Lani, and you may stay on your proverbial soap box as far as I am concerned. I really hope you are correct in your belief that our market driven economy will deliver affordable testing. It feels like we are in the stone age on some of this stuff and another break through is needed to propel us forward into a new era of cancer treatment!

[hutchibk]

The salad metaphor is great. Stay on your soap box... it makes sense.