Neoplasia : The Cancer cell

Neoplasia is uncontrolled new growth, which serves no useful purpose, has no orderly structural arrangement and is undifferentiated or less differentiated in nature with more embryonic characters of the cells.

It is also known as tumor/ neoplasm/ cancer.

Types

1.      Benign neoplasm and

2.      Malignant neoplasm.

Nomenclature

•      If a word ends with ‘oma’, it generally means a tumor/tumour; e.g., fibroma.

•         Here, prefix ‘fibro’ indicates fibrous connective tissue (a particular cell type) and suffix ‘oma’ indicates tumor.

So, fibroma is the tumor of fibrous connective tissue.

•         Epithelial and mesenchymal benign neoplasm generally ends with suffix, ‘oma’ e.g., papilloma, fibroma, lipoma, leiomyoma, adenoma, chondroma, osteoma etc.

•         In case of malignant tumor of epithelial cells, the suffix will be ‘carcinoma’, e.g., squamous cell carcinoma, adenocarcinoma etc. and malignant tumor of mesenchymal tissues, the suffix will be ‘sarcoma’, e.g., chondrosarcoma, osteosarcoma, rhabdomyosarcoma, leiomyosarcoma, liposarcoma, fibrosarcoma etc.

Exception in Nomenclature

•         Lymphoma means a malignant tumor (previously called malignant lymphoma or lymphosarcoma).

•         Melanoma means a malignant tumor (previously called malignant melanoma. Now, melanocytoma (nevi, pigmented mole) indicates a benign tumor; while melanoma indicates a malignant tumor.

•         ‘oma’ does not always mean tumor, e.g., granuloma, hematoma.

•         Teratoma is a neoplasm that contains haphazardly arranged mixture of tissues derived from all germ cell layers, ie, endoderm, mesoderm, ectoderm. In human, it is malignant and is composed of skin, hair, tooth, nerve cell, muscle, bone, cartilage etc. but in animal, it is benign.

•         Meningioma and insulinoma are benign tumors but the effect is fatal.

•         Polyp is the outgrowth that may be inflammatory or hyperplastic or neoplastic.

•         Words without ‘oma’ but is tumor, e.g., basal cell tumor, mast cell tumor. 

•         Occult tumor: Primary origin is undetected but metastasis occurs to other organs causing death of the patient.