Assessing a Case of Early-Stage HER2+ Breast Cancer

Denise A. Yardley, MD:This is a postmenopausal patient who underwent routine screening and mammography. She did not come in with any symptoms. Unfortunately, like many of the patients with breast cancer these days, her disease was detected by an abnormality that showed up on the screening mammogram. That, of course, prompted further evaluation with an ultrasound that looks at the breast and looks at the lymph nodes, and there was a suggestion of some abnormal lymph nodes. And then, the patient was appropriately referred for a biopsy and underwent a core biopsy that revealed a diagnosis of breast cancer.

Now, this breast cancer underwent the typical evaluation for both hormone receptors, which in this case were negative, and for HER2, which is standard for any new diagnosis of breast cancer. That revealed that this case is a HER2-positive breast cancer. At this point, we start thinking about what the best treatment approaches are for this patient. We look at the considerations for neoadjuvant therapy, adjuvant therapy, and the guidelines. I think the NCCN [National Comprehensive Cancer Network] guidelines really help us try to figure out what the next best steps are for this patient to take.

When we look at the NCCN guidelines and look at this postmenopausal 56-year-old lady who has a HER2-positive, hormone receptor-negative breast cancer, we look at a couple considerations for neoadjuvant therapy, and she presented with many of those findings. The concurrent considerations for neoadjuvant therapy look at a tumor size greater than 2 cm, and by imaging, her tumor falls into that category.

There’s also a suggestion of involvement of lymph nodes, and she did undergo an evaluation of the lymph node at the time of her breast biopsy. That did, unfortunately, reveal there was disease in at least 1 of the lymph nodes. That’s a patient who I would typically think of as a good patient for neoadjuvant therapy considerations. I think the guidelines would support that as well, and looking at treatment options, we clearly think about dual HER2-targeted therapy with chemotherapy for the neoadjuvant setting. This particular patient received a recommendation of a taxane and platinum-based regimen with docetaxel/carboplatin given concurrently with Herceptin [trastuzumab] and Perjeta [pertuzumab]. She then underwent surgery following completion of her chemotherapy.

When we look at a patient who comes in post-biopsy, we now have some parameters to start thinking of how we should best approach the patient. This patient clearly had an appropriate workup in terms of an imaging procedure that demonstrated a breast abnormality. She went on to an ultrasound that looked at both the breast and the lymph nodes. And so, we really do want to get a look at that—the axillary contents—to start planning the strategy of neoadjuvant or adjuvant therapy, and even have considerations for the surgeon to perform sentinel node evaluation or full axillary bisection. This patient’s ultrasound did suggest a reason to biopsy a lymph node, and we have now documented lymph node involvement for this patient. This clearly guides us to the consideration of neoadjuvant therapy in this particular case.

The considerations really are, What do we do in terms of systemic evaluation? We now know the patient has HER2-positive, lymph node-involved, hormone receptor-negative disease, and I’m already thinking of the neoadjuvant strategy. It seems quite appropriate for this patient. But I do want to look at her systemic staging studies because we know that this is a high-risk, highly proliferative and aggressive breast cancer, and it may have evidence of disease spreading. It’s unlikely when a patient walks in, but I do consider doing laboratory evaluation to look at liver enzymes for the patient and then get a baseline systemic approach in terms of imaging, whether it’s a CT [computed tomography] scan, PET [positron emission tomography] scan, or a combination of scans to take a look at liver, lung, and bones.

The prognosis for this patient these days is fabulous. I think if we look a little bit back in time, before we had a real understanding of the HER2-signaling pathway—and more specifically, drugs very specifically targeted for this pathway that are now part of standard care, Herceptin and Perjeta in this case—we’ve changed what was previously a very poor prognostic cancer, where patients had a very aggressive disease course. We have now tailored and directed specific HER2 dual-targeted therapy as part of the treatment approach and elevated the cancer to one of the cancers that has the best prognostic outcome if that disease is sensitive to treatment.

Transcript edited for clarity.

A 56-Year-Old Woman Receiving Adjuvant Therapy forHER2+ Breast Cancer

• A 56-year-old postmenopausal woman was referred for evaluation of a left-sided spiculated mass (2.4-cm) with scattered microcalcifications, found incidentally on screening mammography. Mammogram 12 months earlier was normal.
• Ultrasound confirmed a hypoechoic mass of approximately 2.4 cm X 2,3 cm by 1.8 cm at the 2 o’clock position in the left breast, 4 cm from the nipple. Axillary ultrasound demonstrated 3 enlarged lymph nodes with cortex thickening.
• Core biopsy of the breast mass revealed poorly differentiated invasive ductal carcinoma, ER/PR-negative, HER2 IHC 3+; lymph node sampling revealed the presence of breast cancer.
• Staging: T2N1M0
• She received neoadjuvant docetaxel and carboplatin with concurrent trastuzumab and pertuzumab.
• Surgical resection scattered microscopic foci of residual disease spanning 4 mm; no involved lymph nodes
  • Re-staging, ypT1aypN0M0