Aglaia elliptica Blume is one of plants that contain cyclopenta[b] tetrahydrobenzofuran compound with strong cytotoxic effect on various types of cancer cell lines. The objective of this study is to determine the inhibition effect of ethanol extract of A. elliptica leaves on mammary tumor growth in Sprague Dawley female rats induced by 7.12-dimethylbenz[a]anthracene (DMBA). The study was conducted with induction of 50 female rats with DMBA at a dose of 20 mg/kg orally for 11 times. Twenty-five female rats suffering mammary tumor were divided into 5 groups. Three groups were treated with ethanol extract at a dose of 50, 100 and 200 mg/200 g BW one day after the tumor appeared for 30 days, 1 group as a negative control and 1 group as a positive control (doxorubicin 2 μg/200 g BW). The results showed that the induction of DMBA resulting tumor incidence by 74% and tumor multiplicity of 2 nodules/rat. Histopathological analysis of mammary tumor, suggested that the carcinogenesis has reached the level of ductal carcinoma invasive (DCIV). The administration of ethanol extract at dose of 50, 100 and 200 mg/200 g BW suppressed the growth of mammary tumor volume by 30 %, 33.5% and 37.4%, respectively.Aglaia elliptica Blume adalah tanaman dari suku Meliacecae yang mengandung senyawa cyclopenta[b]tetrahydrobenzofuran dengan efek sitotoksik kuat pada berbagai jenis sel kanker. Penelitian ini bertujuan untuk mengetahui efek hambatan karsinogenesis ekstrak etanol daun Aglaia elliptica Blume pada mamae tikus betina galur Sprague Dawley (SD) yang diinduksi 7,12 dimetilbenz[a] antracene (DMBA). Penelitian diawali dengan induksi 50 ekor tikus betina galur SD menggunakan DMBA dosis 20 mg/kg BB secara oral sebanyak 11 kali. Sebanyak 25 ekor tikus betina yang tumbuh tumor mamae dibagi dalam 5 kelompok. Tiga kelompok diberi ekstrak pada dosis 50, 100 dan 200 mg/200 g BB sehari setelah muncu tumor selama 30 hari, 1 kelompok sebagai kontrol negatif dan 1 kelompok sebagai kontrol positif (diberi doksorubisin 2 μg/200 g BB). Hasil penelitian menunjukkan bahwa induksi DMBA memberikan insidensi tumor sebesar 74% dan multiplisitas sebesar 2 nodul/ekor. Hasil analisis histopatologi tumor mamae menunjukkan bahwa tingkat karsinogenesis sampai kategori Ductal Carcinoma Invasive (DCIV). Pemberian ekstrak etanol dosis 50,100 dan 200 mg/200 g BB dapat menekan pertumbuhan volume tumor berturut-turut sebesar 30%, 33.5% dan 37.4%
