Neoplasia and the most important features of Benign and malignant tumor

Neoplasia
Abnormal mass of tissue the growth of which is exceed and uncoordinated that of normal tissue and it persists even after cessation of the external stimuli .

Neoplasia is divided into benign and malignant tumours .

Feature Benign malignant
Histological feature Similar to tissue of origin
Nuclei is normal
Cells uniform in size and shape Many differ from tissue of origin
Nuclear pleomorphism
Cellular pleomorphism

Mode of growth Remain localized Infilteration and metastasis
Rate of growth Slower Faster
Clinical effects Local pressure effects
Hormonal secretion
Cure by local excition Local pressure and destructive effects , inappropriate Hormonal secretion ,non-metastatic metabolic and neurological complications ,not cure by local excition






The examples of benign tumours are :

Lipoma
It’s a benign tumour of adipose tissue of connective tissue origin , its arise anywhere in the body most commonly in the back , shoulder and proximal parts of limbs , usually affect women over fourty years old.

Clinically it presents as a single painless mass and can be painful , in this condition called angiolipoma

Macroscopically :it either single or multiple , soft ,mobile ,ill defined or well defined yellow colour as seen in picture(1) .

Microscopically : it consists of mature fat cells ,the cells uniform in size and shape ( large polygonal cell , peripheral nucleus , empty cytoplasm ) ,the tumor surrounded by fibrous capsule . as seen in picture(2)



Leiomyoma (Fibroids) of uterus
It’s a benign tumour of smooth muscle cell arise in the myomaterium of the uterus, there is :
1- Genetic predisposition (there is 40% of cases have chromosomal abnormalities , more in black female than white )
2- Estrogen dependant tumour that increase in size during pregnancy and in women taking oral contraceptive pills and regress post menopausal.

Clinically: It affect women at the reproductive age group presents as either asymptomatic (small size) or large mass to cause a different symptoms like prolong heavy menstrual bleeding , back pain, pelvic discomfort .
Complications : Vaginal Bleeding, Abortion , Infertility.

Macroscopically :it either single or multiple , firm, gray-white colour, small - large mass full the pelvis or abdominal cavity ,the whorl pattern of smooth muscle bundles is characteristic , the tumour can be intramural , submucosal ,subserosal . as seen in picture(3)

Microscopically :
1- Interlacing bundle of smooth muscles fibers arranged in the whorl pattern contain densely packed smooth muscle cells.
2- We may see the degenerative changes include fibrosis , patchy necrosis ,hyaline changes ,calcification, thrombosis and hemorrhage. as seen in picture(4)