Hi. It's Dr Kathy Miller here from Indiana University, with a little preview of what you might look for from the breast cancer sessions at the upcoming American Society of Clinical Oncology (ASCO) meeting. It's going to be a bit of an up-and-down year for us. For two trials that we've heard about in press releases, we'll finally get to see the data. First, the positive trial—another in the PALOMA series looking at palbociclib, this time in combination with fulvestrant in patients with previously treated ER-positive disease. This, you recall from the press release, is a trial stopped early by the data monitoring committee because the trial was clearly positive. They thought it was unethical to continue. We'll finally get a first look at the data to see how good is good and whether this will impact our practice.
We'll also get the results of a trial that didn't turn out the way we thought. We heard—by way of press release again—that the MARIANNE trial looking at T-DM1 alone or T-DM1 in combination with pertuzumab as the initial chemotherapy for patients with HER2-positive metastatic disease was not superior to a standard arm of trastuzumab and a taxane.[3,4] That's a bit of a surprise.
T-DM1, we know, had been quite superior in previously treated patients. We'd seen superiority in a randomized phase 2 trial that led up to this. We saw the CLEOPATRA trial suggesting that simply adding pertuzumab to plain old trastuzumab and a taxane was markedly superior. I think many of us thought T-DM1 would be better and that you probably could get more benefit from adding pertuzumab.
In the case [of the MARIANNE data], the details are going to be a bit more difficult to decipher and will require more thought. The press release told us that neither the T-DM1-alone nor the T-DM1-plus-pertuzumab arm was superior, but they did meet a formal test for noninferiority. We're going to have to look carefully at the toxicities and the cost (what was that noninferiority boundary?) and think about what the role of T-DM1 should be in untreated patients, or at least as the initial therapy for metastatic disease. The MARIANNE results, I think, also call into question an ongoing adjuvant trial that looks at swapping out T-DM1 for a component of adjuvant therapy for patients with high-risk disease.
I found one unexpected gem as I was looking through the abstracts. I want to point you to a poster session for the SHAVE trial. This is a trial by one of our surgical colleagues, Dr Anees Chagpar, that looked at whether a shave margin after initial lumpectomy might decrease the risk for positive margins and the need for re-excision.
The trial was designed perfectly to address this question. Patients consented prior to surgery. The surgeon did a lumpectomy exactly as he or she would. And at the time the surgeon said, "I'm done," patients were then randomized, the envelope was opened in the OR, and the surgeon took either additional shave margins—an additional millimeter or two all around the lumpectomy cavity—or simply closed the envelope. Rates of positive margins and re-excision were cut by more than half with this simple technique.
We'll need to look at the outcome of cosmesis, but this is a really important trial that could change surgical management, decrease the cost, decrease the rate of re-excision, and decrease the number of patients who opt for mastectomy instead of re-excision. I'm sure there will be other notable studies.
I look forward to seeing you in Chicago. If you're there, please feel free to look for me. I'd love to hear your thoughts in person.
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Cite this: SHAVE a Big Plus in Breast Cancer - Medscape - May 22, 2015.