What considerations underlie these choices?
In 2016, we're lucky that we have a number of choices. Many of them have only been studied in the first- or second-line metastatic setting and many of them have only been studied with a type 2 armoatase inhibitor. For the case of the CDK inhibitors, that's letrozole or fulvestrant, that's our other agent that we can combine with our endocrine agents. We don't really have a lot of data about the use of CDK inhibitors past the second-line, whereas with the use of everolimus, we've studied that in patients who have progressed on a type 2 armoatase inhibitor. That's the eligibility criteria for the BOLERO2 study.
I think in terms of data-driven decision making, we have data in this setting, and also in this very practical thought of "what targeted agent can I get covered in combination with anti-estrogen therapy," I think everolimus is a good choice. If you were really worried about her liver lesions, or she was having bumps in her liver function test, it's also appropriate to consider capecitabine, which is an oral chemotherapy agent, but I don't think there's any harm in trying an 8-week course of a targeted agent and anti-estrogen therapy. I would just keep a close eye on her and, given that she's 3 years out from her initial diagnosis and is still having minimal symptoms, I think it's very appropriate to choose an anti-estrogen strategy.
ER+/HER2-Breast Cancer: Case 1
Angela is a 56-year-old woman, who in 2013 was diagnosed with a 4 cm IDC of the left breast, ER positive at 50%, PR negative, and Her2 negative. She was treated with four cycles of neoadjuvant doxorubicin and cyclophosphamide, followed by twelve weeks of paclitaxel.
She then had a left MRM with AD, showing a residual 1.5 cm tumor with 3/10 LN positive
She received anastrozole, and in early 2015 she complained of low back pain and a bone scan revealed multiple areas of uptake in the lumbosacral spine
PET-CT revealed lytic lesions in the lumbosacral spine and pelvis, and a 2 cm low attenuation lesion in the liver with a PET SUV value of 10, indicating malignancy
She was placed on denosumab 120 mg SQ monthly, and fulvestrant 500 mg IM monthly. Her pain resolved within 2 months, and on follow-up CT qt 4 months her bone lesions appeared sclerotic and her liver lesion had reduced to 1 cm. Her fulvestrant and denosumab were continued.
In early 2016 she again complained of worsening low back pain and left hip pain
Repeat PET-CT demonstrated new lytic lesions in the left iliac crest as well as an enlargement of the liver lesion to 3 cm