To Extend or Not Extend? Evaluating the Need for Extended Endocrine Therapy in Patients With Early-Stage HR+ Breast Cancer
Welcome to this Clinical Case Series learning module!
Here's how it works:
- Read these 3 case studies on the AP role in evaluating the need for patients with early-stage HR+ breast cancer to receive extended endocrine therapy.
- Answer the poll next to each case to see how your colleagues are managing these patients. You'll see results in real time.
- Continue your learning by watching a recording of a webinar presented by Michelle Butaud, APRN, ANP, AOCNP, CBCN.
BCI Test Use in Younger Women
Clinical Pearl: BCI test results can be a helpful tool for younger patients.
A 55-year-old female was diagnosed with a stage II T2N1M0 left breast multifocal invasive ductal carcinoma, grade 2, ER 99%, PR 71%, HER2/neu 0 by IHC and Ki67 18%. She completed 4 cycles of doxorubicin HCl (Adriamycin)/cyclophosphamide (AC) followed by 12 weekly cycles of paclitaxel, followed by a left breast skin-sparing mastectomy with left axillary lymph node (LN) dissection. She had residual disease consistent with treatment effect measuring 8 x 8 cm comprising 1% of the area sampled. Clear margins were obtained. Additionally, she had residual isolated tumor cells in one of 18 LNs. She completed radiation therapy and initiated tamoxifen due to premenopausal status at time of diagnosis. Her last menstrual period was 1 year ago. She has been on tamoxifen for 4.5 years. Currently, she is experiencing some mild arthralgias and hot flashes. Additionally, she has osteoporosis and is on denosumab.
The patient is seen in the clinic for follow-up. At this point, her options are as follows: recommend continuing tamoxifen for 6 more months, for total of 5 years of endocrine therapy; consider ordering a Breast Cancer Index (BCI) test to determine if she is likely to benefit from extended endocrine therapy; recommend that the patient continue on tamoxifen, for a total of 10 years of endocrine therapy; or discuss drawing estradiol levels and switching to an aromatase inhibitor (AI) if she is postmenopausal, with the possibility of taking an AI for an additional 5 years.
Based on young age, tumor size, lymph node involvement, and Ki67 percentage, the advanced practice provider decides to order a BCI test. The predictive result indicates “yes,” that she is likely to benefit from extended endocrine therapy. The prognostic result shows that with a total of 5 years of therapy, her risk of late distant recurrence between 5 and 10 years is 23.2%, and with a total of 10 years of adjuvant endocrine therapy, her risk of late distant recurrence decreases to 7.7% to 9.7%. In light of these results, the patient was continued on tamoxifen due to having osteoporosis.
BCI Test and Endocrine Therapy Side Effects
Clinical Pearl: BCI test results may be helpful for patients who are experiencing side effects from endocrine therapy.
A 70-year-old female was diagnosed with a stage I T2N0M0 left breast invasive ductal carcinoma, grade 2, ER 99%, PR 5%, HER2/neu 2+ by IHC, amplified by FISH, Ki67 17%. She underwent a left breast segmental mastectomy with sentinel lymph node (LN) biopsy. Her invasive tumor was 3.5 cm. There was no lymphovascular invasion, and the 3 LNs sampled were negative for disease. She completed 4 cycles of adjuvant doxorubicin HCl (Adriamycin)/cyclophosphamide (AC) followed by 4 cycles of docetaxel (Taxotere)/trastuzumab (Herceptin)/pertuzumab (THP) followed by HP therapy to complete 1 year. She also had radiation therapy. She was initiated on letrozole and is now 4 years into her therapy. Her side effects include moderate arthralgias, mild osteopenia, and vaginal dryness.
The patient is seen in the clinic for follow-up. At this point, her options were as follows: recommend she continue letrozole for 1 more year, for a total of 5 years of endocrine therapy; consider ordering a Breast Cancer Index (BCI) test to determine if she is likely to benefit from extended endocrine therapy; recommend that the patient continue on letrozole for a total of 10 years of endocrine therapy; or discuss continuing on endocrine therapy for 10 years, but plan to switch her to tamoxifen at year 5.
Based on the patient’s significant symptom burden from endocrine therapy, the advanced practice provider chooses to order a BCI test. The predictive result indicates “yes,” that she is likely to benefit from extended endocrine therapy. The prognostic result shows that with a total of 5 years of therapy, her risk of late distant recurrence between 5 and 10 years is 7.1%, and with a total of 10 years of adjuvant endocrine therapy, her risk of late distant recurrence decreases by 65%. Based on these BCI test results, the patient elected to stay on letrozole, and her symptoms were managed pharmacologically. She was initiated on denosumab due to osteopenia, and moisturizers were recommended for vaginal dryness.
Using the BCI Test Based on Clinicopathological Features
Clinical Pearl: Extended endocrine therapy in patients with significant clinicopathological features and advanced age.
A 78-year-old female was diagnosed with a stage II T2N1M0 right breast invasive lobular carcinoma, ER 99%, PR 40%, HER2/neu 0 by IHC, and Ki67 7%. She had a total mastectomy with axillary lymph node (LN) dissection with an invasive component measuring 5.7 cm. 1/12 positive LNs and clear margins were found. There was no lymphovascular invasion. She received 4 cycles of doxorubicin HCl (Adriamycin)/cyclophosphamide (AC) followed by 12 weekly cycles of paclitaxel, followed by radiation therapy. She has now been on letrozole for 5 years. She is experiencing mild to moderate arthralgias and osteopenia.
The patient is seen in the clinic for follow-up. At this point, the options were as follows: let her know she is now finished with letrozole, having had a total of 5 years of endocrine therapy; consider ordering a Breast Cancer Index (BCI) test to determine if she is likely to benefit from extended endocrine therapy; recommend she continue on letrozole for a total of 10 years of endocrine therapy, and refer her to bone health; or recommend she stop letrozole and switch to tamoxifen for 5 years, to complete a total of 10 years of endocrine therapy.
Based on this patient’s clinicopathological features (tumor size, lymph node involvement, etc.), the advanced practice provider (APP) chooses to order a BCI test. The predictive result indicates “no,” that she is not likely to benefit from extended endocrine therapy. The prognostic result shows that with a total of 5 years of therapy, her risk of late distant recurrence between 5 and 10 years is 15.4%. Based on these BCI test results, the APP decides to discontinue letrozole.
Meet the Faculty
Michelle Butaud
APRN, ANP, AOCNP, CBCN
MD Anderson Cancer Center
Michelle Butaud, APRN, ANP, AOCNP, CBCN, is a nurse practitioner at MD Anderson Cancer Center, specializing in breast medical oncology. With over 25 years of oncology nurse practitioner experience and 13 years in breast oncology, Michelle works both in an independent clinic and with multiple breast medical oncologists. She is a Certified Breast Care Nurse and Advanced Oncology Certified Nurse Practitioner, as well as a member of the Oncology Nursing Society, Texas Nurse Practitioner Association, American Organization of Nurse Leaders, and Nursing Professional Development Association.
Let us know what you'd like to learn more about at jadpro-editor@broadcastmed.com