Neoplasm

Neoplasm its Types and Nomenclature

 Neoplasm, Oncology, Differentiation, Tumors, Mixed Tumors, Teratoma, Anaplasia, Components of neoplasm, Desmoplasia, Types Of Neoplasms (Tumors), Nomenclature Of Tumors, Papilloma, Cystadenoma, Polyps, Fibroma, Myxoma,Lipoma.

    Neoplasia means new growth and is characterized by unceasing abnormal and excessive proliferation of cells.

Neoplasm

    The neoplasm (commonly called tumor) is defined as the abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissue, and persists in the same excessive manners after the cessation of the stimuli which evoked the change.

Oncology

The study of neoplasm (tumor) is called oncology.

Differentiation

    Th extent to which the neoplastic parenchymal cells resemble their normal parent cells, both morphologically and functionally is called differentiation.

Anaplasia

    Irreversible loss of differentiation is called anaplasia.

Components of neoplasm

    Parenchyma constitute the proliferating part of the neoplasm Stroma. It is made up of connective tissue, blood vessels and lymphatics. It provides support for the growth of parenchymal cells.

Desmoplasia

The excess of stromal component in a tutor is called desmoplasia and such a tumor is called scirrhous tumor

Types Of Neoplasms (Tumors)

A) Benign tumors

B) Malignant tumors

Benign tumor

    It is the tumor characteristics of which are relatively innocent such as:

It will remain located.

It cannot spread to other sites Amenable to local surgical removal.

Patient survives.

Malignant Tumor

    It is also called cancer. The malignant tumor is destructive and dangerous, having characteristics such as It can invade and destroy adjacent structures. It spreads to distant sites (metastasis).

Patient dies

Nomenclature Of Tumors

    The tumor is named on the basis of Cell or tissue of origin

Whether it is benign or malignant.

Benign Tumors

In general. These are designated by attaching the suffix " oma " to the cell of origin.

Examples:

a) Benign tumor arising from fibroblastic cells is called Fibr-oma (Fibroma)

b) Benign tumor arising from meninges is called meningi-oma (meningioma).

    Important note Benign tumors of mesenchymal cells generally follow the above rule of just attaching on to the cell of origin. Nomenclature of benign tumors of epithelial cell is more complex. They are named on multiple basis ep

Cell of origin

Microscopic architecture,

Macroscopic pattern.

Examples of benign epithelial cell tumors,

Adenoma:

    The benign epithelial neoplasm that forms glandular pattern as well as those derived from gland although not necessarily reproducing glandular pattern is called adenoma eg. Benign epithelial neoplasm that arises from renal tubular cells growing in the form of glands would be termed as adenoma, while epithelial tumors arising from adrenal gland even not grow in gland pattern would also be called adenoma.

Papilloma

    The benign epithelial neoplasms producing microscopically or macroscopically visible finger like projections from epithelial surfaces are called papilloma's

Cystadenoma

    When retention of secretion is marked, a cyst forms in adenoma and such tumor is called cystadenoma.

Polyps

    The tumor that produces macroscopically visible projection above a mucosal surface ( eg into gastric or colonic lumen) is called polyp. Examples of benign mesenchymal cell tumors

Fibroma

    This benign tumor arises in subcutaneous tissues, fascia, periosteum, kidney and ovary.

Myxoma

    This benign tumor is a variant of fibroma and represents a degenerative changes characterized by accumulation of ground substances in mature tissues.

Lipoma

    This benign tumor arises from fat of cells in subcutaneous tissue arises from cartilage

Chondroma

This benign tumor arises from cartilage

Osteoma

This benign tumor arises from bones,

Myoma

    It arises from muscles and is divided into Leiomyoma: It is benign tumor of smooth muscles. It can occur wherever there is smooth muscle present but is especially common in uterus (mostly) and media of blood vessels. It also occurs in GIT, ovary and kidney.

Rhabdomyoma: This is a rare benign tumor of skeletal and heart muscles.

Malignant Tumors

    The nomenclature of malignant tumors follows the same rules as for benign tumors with certain additions. There are two types of malignant tumors:

Carcinoma

    The malignant tumors of epithelial cell origin are called carcinoma. The word carcinoma is attached to the type of tissue eg , malignant epithelial tumor of renal cell is called renal cell carcinoma.

Sarcomas

    The malignant tumors arising in mesenchymal tissues are called sarcomas. The word sarcoma is attached to the type of tissue eg malignant tumor of fibroblastic cells is called fibro-sarcoma (Fibrosarcoma).

Examples of carcinoma

Adenocarcinoma

    The carcinoma in which neoplastic epithelial cells grow in gland-pattern is called adenocarcinoma. also specified eg Tissue of origin is also adenocarcinoma of renal cell, stomach, colon, breast, gall bladder, prostate and uterus.

    Squamous cell carcinoma The carcinoma in which neoplastic cells resemble stratified squamous epithelium is called squamous cell carcinoma. The carcinoma arising from the area either covered by stratified squamous epithelium ( eg skin, oral cavity, esophagus) or from the epithelium which has undergone metaplasia from columnar to squamous type as seen in gall bladder, bronchi and cervix.

    Some variations Lymphoma, mesothelioma, melanoma and seminoma are malignant tumors although they have suffix " oma " a characteristic of benign tumors.

Examples of sarcomas

Fibrosarcoma

    This tumor arises most commonly from fascia, intermuscular septa, subcutaneous tissues and periosteum.

Chondrosarcoma:

    This malignant tumor arises in the cartilage, most commonly at the ends of long bones.

Osteogenic sarcomas:

    This malignant tumor arises in the bones usually in the upper end of tibia, lower end of femur and upper end of humerus.

    Giant cell tumor of bone ( osteoclastoma ) This malignant tumor arises in the multinucleated giant cell in the spindle cell stroma.

Leiomyosarcoma:

    This malignant tumor arises in smooth muscles, and almost all of them occur in the uterus.

Rhabdomyosarcoma:

    This malignant tumor arises in striated muscles usually in children. Skeletal muscles are rarely affected as compare to bladder and uterus.

Liposarcoma:

    This malignant tumor arises in fat cells in subcutaneous tissue of arm, shoulder and buttocks.

Mixed Tumors

    The Tumors containing more than a cell type (mesenchymal or epithelady we called mind

    Beniga: Pleomorphic adenoma of salivary gland, bodenoma of breast

    Malignant: Malignant moved summer of salivary and Wilm's tumor of kidney, malignant cystsadenama phyllodes of breast,

Teratoma

    These are the tumors containing mature of immature cells or tissues representative of more than one germ layer and sometimes of at three (ectoderm, mesoderm and endoderm . They originate from differentiation of totipotential cell the cells more commonly present in ovary and testes having capacity to differentiate into all cell types to be found in the adult bodies . The teratoma may be benign or malignant. 

    The benign tumor is called imature or dermoid cyst while the malignant tumor is called immature teratoma. The vast majority of teratomas occur in gonads, more common in ovary then testis Less frequently tremors are found in anterior mediastinum retroperitoneal tissue, and intracranially retroperitoneal tissue, and intracranially.