A study of assessing cardiotoxicity by MUGA technique in patients treated for carcinoma breast

Introduction: Adriamycin is one of the commonly used chemotherapeutic drugs in breast cancer which induce cardiotoxicity ranges from benign arrhythmias to potentially lethal cardiomyopathy. Aim: To study on assessing adriamycin induced early cardiotoxicity in breast cancer with MUGA scan by estimating LVEF. Materials and methods: In this prospective study with a subject of 30 female patients, histologically confirmed breast cancer stage-I –III without any co-morbidities and higher risk factors (as per protocol) with baseline LVEF >50% estimated with TC-99M MUGA scan and 2D Echo received 4 cycles of AC + RT + Paclitoxal + HT. Chemotherapy given based on BSA with dosage of A=60 mg/m2, C = 600 mg/m2; EBRT = 5040 Gy/5000 gy to chest wall and p=175 mg/m2. Results: Out of 30 patients, 4 patients received320 mg; 14 patients received 360 mg; 4 patients received 380 mg; 5 patients received 400 mg; 1 patient received 340 mg; 1 patient received 450 mg and 1 patient received 600 mg. In all the patients there is a decline in LVEF from baseline to 1st MUGA scan and Baseline to 2nd MUGA scan. From baseline - 2nd MUGA scan out of 30 patient, 3 patients had protocol defined decline LVEF i.e. <50% at doses of 380 mg, 400mg and 600 mg respectively i.e. 3 patients developed protocol defined subclinical cardiotoxicity. 2D Echo was also done in all patients at 3rd MUGA scan. In 2D Echo even though there is a decline in LVEF, no patient developed protocol defined subclinical cardiotoxicity. Mean and standard deviation (SD) was 51.97±2.72 for MUGA-3 based on null lypothesis, p value is scored as = 0.9 which is insignificant for adriamycin cardiotoxicity. Conclusions: Out weighing the benefits and risks at lower cumulative doses, adriamycin is still considered as treatment of choice. Specific cardiac monitoring guidelines should be formed to evaluate adriamycin cardiotoxicity.