HER2 Support Group Forums - View Single Post - Herceptin side-effects

Lolly · 02-01-2006, 04:28 PM

Judy, I found this study which may answer some of your questions, but the conclusion is that really not much is known about how Herceptin damages the heart. Lolly

Influence of trastuzumab on epirubicin pharmacokinetics in metastatic breast cancer patients
http://annonc.oxfordjournals.org/cgi...full/14/8/1222

"...The mechanism by which trastuzumab treatment leads to an increased incidence of cardiac dysfunction in patients treated with anthracyclines has not yet been defined. A strong expression of HER2 receptors was not observed in the tissue obtained from heart biopsies from 60 patients with cardiac dysfunction, nor from 25 breast cancer patients with or without previous anthracycline treatment [17]. Nonetheless, cardiotoxicity seems to be related to myocardial uptake of trastuzumab [18]. In fact, it was observed that, in a group of 20 patients, seven had myocardial uptake of radiolabeled trastuzumab. Six out of the seven patients developed cardiotoxicity, and the seventh had episodes of cardiac arrhythmia during the administration of trastuzumab. In the 13 patients without myocardial uptake, no adverse cardiac effect occurred. Recent animal studies have demonstrated that in ErbB2-deficient conditional mutant mice there is a progressive onset of multiple independent parameters of dilated cardiomyopathy, the same type of cardiac dysfunction evident in patients treated with trastuzumab [5, 19], and that ErbB2-deficient cardiomyocytes are more susceptible to anthracycline-induced cell death [5]...."

02-01-2006, 04:28 PM	#5
Lolly Senior Member Join Date: Aug 2001 Location: Oregon Posts: 1,756	Judy, I found this study which may answer some of your questions, but the conclusion is that really not much is known about how Herceptin damages the heart. Lolly Influence of trastuzumab on epirubicin pharmacokinetics in metastatic breast cancer patients http://annonc.oxfordjournals.org/cgi...full/14/8/1222 "...The mechanism by which trastuzumab treatment leads to an increased incidence of cardiac dysfunction in patients treated with anthracyclines has not yet been defined. A strong expression of HER2 receptors was not observed in the tissue obtained from heart biopsies from 60 patients with cardiac dysfunction, nor from 25 breast cancer patients with or without previous anthracycline treatment [17]. Nonetheless, cardiotoxicity seems to be related to myocardial uptake of trastuzumab [18]. In fact, it was observed that, in a group of 20 patients, seven had myocardial uptake of radiolabeled trastuzumab. Six out of the seven patients developed cardiotoxicity, and the seventh had episodes of cardiac arrhythmia during the administration of trastuzumab. In the 13 patients without myocardial uptake, no adverse cardiac effect occurred. Recent animal studies have demonstrated that in ErbB2-deficient conditional mutant mice there is a progressive onset of multiple independent parameters of *dilated cardiomyopathy*, the same type of cardiac dysfunction evident in patients treated with trastuzumab [5, 19], and that ErbB2-deficient cardiomyocytes are more susceptible to anthracycline-induced cell death [5]...."