Neoplasia PDF - Overview & Nomenclature

Neoplasia Dr. Sudha Arumugam  Learning objectives  To explain the concept of neoplasia.  To define the nomenclature used.  To explain the aetiology and features of neoplasia, both benign and malignant neoplasms.  To summarise & illustrate the spread, grading, staging and inv...

Neoplasia Dr. Sudha Arumugam  Learning objectives  To explain the concept of neoplasia.  To define the nomenclature used.  To explain the aetiology and features of neoplasia, both benign and malignant neoplasms.  To summarise & illustrate the spread, grading, staging and investigations. 2 Definition : “An abnormal mass of tissue, the growth of which exceeds and is uncoordinated with that of the normal tissues and persists in the same excessive manner after cessation of the stimuli which evoked the change”..........................RUPERT WILLIS Progressive, Purposeless, Pathologic, Proliferation of cells. Uncontrolled cell division 3 Terms to understand  Cancer is the common term for all malignant tumours.  Neoplasia literally means ‘ new growth’ and the new growth is called as a neoplasm.  Oncology is the study of tumours or neoplasms. 4 Non-Neoplastic Proliferation: *Controlled & Reversible  Hypertrophy – Size  Hyperplasia – Number  Metaplasia – Change  Dysplasia – Disordered Neoplastic Proliferation: Uncontrolled & Irreversible*  Benign  Localized, non-invasive.  Malignant (Cancer)  Spreading, Invasive.  Benign neoplasms  Designated by attaching the suffix –oma to the cell of origin.( e.g. fibroma, chondroma, lipoma).  They are variably classified, some based on their cells of origin, others on microscopic structure, and still others on their macroscopic patterns.  They do not invade adjacent tissues borders, nor do they spread to distant sites. 8  Nomenclature of Tumors Benign Tumors Epithelial Mesenchymal Benign tumor arising from Benign connective tissue glandular structure is called tumors have prefix denoting adenoma the cell of origin Benign tumor arising from E.g.: epithelial surface having Fibroma papillary structure is called Osteoma papilloma Chondroma E.g.: Lipoma Squamous cell Papilloma Transitional cell papilloma  Nomenclature of Tumors MALIGNANT TUMORS Epithelial Mesenchymal Carcinoma Sarcoma Squamous cell carcinoma Fibrosarcoma Adenocarcinoma Osteosarcoma Rhabdomyosarcoma Transitional Cell Carcinoma Leiomyosarcoma Malignant tumors of the blood cells are called “Leukemias”  Benign Malignant  Slow growing,  Fast growing,  capsulated,  non capsulated,  Non-invasive  Invasive & Infiltrate  do not metastasize,  Metastasize.  well differentiated,  poorly differentiated,  suffix “oma” eg.  Suffix “Carcinoma” Fibroma. or “Sarcoma”  Adenoma Gross: Polypoid Micro: Proliferation of gowth benign glands Lipoma Gross: Encapsulated Micro: Mature bland yellowish lobulated adipocytes Leiomyoma Gross: Well circumscribed Micro: bland spindle cells in fascicles  Exceptions to nomenclature rules Some nonneoplastic lesions with- oma suffix: Granuloma, Atheroma, Mycetoma, Tuberculoma Some malignant tumors with -oma suffix named like benign tumors Melanoma, Lymphoma, Myeloma Some tumor like malformations Hamartoma, Choristoma Hamartoma: mass of disorganized but mature specialized cells or tissue native to the particular site Bronchial epithelium Cartilage Choristoma Normal tissue in foreign location – non neoplastic Eg: pancreatic tissue under small bowel mucosa, Rest of adrenal gland tissue under renal capsule Tumors with more than one parenchymal cell type Teratoma Tumors arising from totipotent cells and representing all 3 germ cell layers- ectoderm, endoderm & mesoderm. Teratomas most often occur in gonads. Dermoid Cyst Benign ovarian teratoma with preponderant ectodermal differentiation  Thank you References: Pathologic Basis of disease – Robbins & Cotran, 10th Ed General & systemic pathology – Underwood, 6th Ed Principles of Internal Medicine – Harrisons, 20th Ed Aids to Pathology – Dixon/ Quirke, 4th Ed Surgical Pathology – Ackerman, 10th Ed; http://clinicalpathology.wordpress.com/ Images: Pathmax, Webpath, UWMed, Columbia Atlas, Images scanned from Robbins http://clinicalpathology.wordpress.com/