Histological study for murine mammary adenocarcinoma implanted in female Albino mice

Abstract

The current study was carried out in University of Kufa/ College of Veterinary Medicine during the period extending between October 2012 and August 2013, The aime of present study to follow the histological changes of growing tumor in female albino mice which were injected with cells of murine mammary adenocarcinoma AM3. The study included use of (40) females albino mice at age (6-8) weeks ,( 25)g weight average . All mice were injected by cells of murine mammary adenocarcinoman (AM3) in subcutaneous of femoro – dorsal region , and ascending to cervical region. The tumor was successfully implanted into (28) mice .These mice divided into four groups , each contains seven tumor-bearing mice . The animals of the first group subjected to the investigations after (48) hrs from implantation , while those of (2nd,3rd), and (4th) groups after 10,20,30 days respectively . The gross examination of the animals of different groups showed that the tumor grew as irregular projection with loss of hair and erosion of overlying skin with milky discharge.The post-mortem examination revealed that the tumor mass was divided into small lobules with various coloures and the tumor mass surrounded by fibrous tissue which increase in thickness as the tumor increased in the age . Extensive areas of necrosis were noticed in the centers of the tumor masses . The microscopic examination of tumor masses in the first group revealed there were sub cataneous small aggregation of tumor cells at the implantation region as well as dispersion of the implantated tumor cells .The inflammatory cells ,especially neutrophils were infiltrated . In the second group ,the tumor masses showed lobulation by fibrous septa with proliferation of new blood vessels with congestion of them. Infiltaration of inflammatory cells , particularly the lymphocytes . The tumor cells arranged as ribbons and acini ,characterized by hyperchromacia pleomorphism , high N/C ratio as well as appearance of mitotic figures . The histological features of the third group revealed increase in the fibrous tissue with extensive necrotic areas and loss of architecture , these appeared in the fourth group in addition to the presence of cellular debris with dead inflammatory cells.