Early-Stage Monitoring and Adverse Event Mitigation for Patients with HER2-Postitive Breast Cancer
Dr. Joyce O’Shaughnessy closes the discussion with considerations for clinicians on monitoring patients with HER2-psotive breast cancer.
Joyce O’Shaughnessy, MD: For patients with early-stage HER2-positive breast cancer during their chemotherapy treatment, I see them every three weeks while they're getting their chemotherapy. It's usually docetaxel, carboplatin, trastuzumab, and pertuzumab. And then once they have their surgery, if they're getting TDM1 in the adjuvant setting, I continue to see them every three weeks during their TDM1 treatment. If they're a pathologic complete response and they're going to get trastuzumab/pertuzumab, they come in every three weeks for their treatment, but I see them in person every nine weeks until they finish up their adjuvant, trastuzumab and pertuzumab. Once patients finish their, HER2-directed therapy for their early HER2-positive breast cancer, we're just following them at that point. Now they're on endocrine therapy. If they're HR+, if they're premenopausal, they'll be getting an LH or H agonist along with their aromatase inhibitor. So they'll be coming in generally every four weeks to get their LH agonist. We tend to see patients every three months for the first year to two. And then we go over generally to every six months till year five. And then we go annually there, after. My practice, if patients have HR- HER2-positive breast cancer, when they reach seven years, their chances of being cured are exceedingly high. I usually give them the option of being followed up by their primary care physician or practitioner at that point, if they're HR+, HER2-positive I generally will continue to see the patients annually after that five-year mark. We don't do any particular surveillance with regard to blood tests or x-rays. We do a careful history and physical examination following up on any concerns. We get annual mammograms. If patients have intact breasts, we get annual mammograms. We do encourage patients to have general, well-woman care, which usually involves a visit with their family practice or internal medicine practitioner, which generally involves annual blood work. Sometimes an annual chest x-ray this is well-woman care. And of course the usual well-woman things such as colonoscopies on schedule et cetera. So that's how we monitor patients with HER2-positive early breast cancer.
It's very important in the curative setting that patients be able to get the proven therapy, to have the highest chances of cure for their HER2-positive breast cancer. That's particularly important when chemotherapy is being combined with trastuzumab and pertuzumab. The main toxicities are myelosuppression as well as diarrhea from the combination of pertuzumab and chemotherapy. Very important we really tell patients about it. I have them take too loperamide after the first loose stool of each day and then one loperamide after each subsequent loose stool of each day, I ask them to keep careful track of how many loose stools, what day it starts, what day it ends how many loperamide they're taking to eat bland diet during the days of the diarrhea. This is the main issue. There are patients who will get grade three diarrhea, then they require a dose reduction of their chemotherapy, but you keep the trastuzumab and pertuzumab going. Usually, with dose reduction of the chemotherapy patients, they'll have only date grade one or two diarrhea tends to get better with each subsequent cycle. Once patients finish their chemotherapy, and they're getting their trastuzumab/pertuzumab by itself, most patients don't have diarrhea. Most patients don't have any toxicities. We do have to monitor, cardiac echo their heart function every three months while they're getting the trastuzumab/pertuzumab. But most patients don't have diarrhea. Some will have low-grade diarrhea from the combination, but it's usually with the chemotherapy. But the use of loperamide, bland diet, good hydration, and calling the doctor if need be for IV hydration, electrolyte checking and repletion, and then dose reduction if necessary are the strategies we use to make sure patients can get their curative chemotherapy trastuzumab and pertuzumab.
