Neoplasia and Cancer Pathology Flashcards

Comprehensive vocabulary flashcards covering concepts of cellular growth abnormalities (-plasias), benign vs. malignant tumors, terminology, genetic mechanisms, multistep carcinogenesis, metastasis, staging, grading, effects on the body, and cancer treatment principles.

Hypoplasia

A condition characterized by fewer cells than what is deemed a normal amount (usually benign), such as micromastia (postpubertal female breast underdevelopment).

Hyperplasia

An increase in cell number under the control of normal proliferation regulatory mechanisms, occurring as a result of external stimuli like callus formation on skin exposed to trauma or pressure.

Neoplasia

Meaning "new growth", it denotes abnormal multiplication and cellular growth due to the loss of normal proliferation regulation and absence of stimuli, also known as "cells manifesting hyperplasia with atypia".

Dysplasia

A change in normal cell shape, size, and organization, usually in response to chronic irritation (such as cigarette smoke or inflammation); changes are reversible if the stimulus is removed, otherwise cells become metaplastic.

Metaplasia

A change in cell type, such as ciliated columnar epithelium of the respiratory surface becoming stratified squamous epithelium after prolonged irritation from smoking; reversible if the stimulus is removed, otherwise cells become anaplastic.

Anaplasia

A reversal in differentiation (dedifferentiation) or loss of mature structural and functional features of a cell or tissue, where a greater degree indicates more aggressive malignancy; characteristic of cancerous tumors and irreversible in nature.

Benign Growth

A tissue growth that more closely resembles the original tissue type (low anaplasia), is encapsulated, grows slowly with little vascularity, is rarely necrotic, does not invade adjacent tissues or metastasize, and generally has a good prognosis.

Malignant Growth

A tissue growth lacking tissue-specific differentiation (greater degree of anaplasia), characterized by rapid invasive growth, metastasizing nature, frequent necrosis, dysfunction, and poor prognosis if untreated.

Lipoma

A benign tumor originating in adipose tissue.

Neuroma

A benign tumor originating in neural tissues.

Adenoma

A benign tumor originating in glandular tissue.

Carcinoma

A malignant tumor of epithelial origin, representing $90\%$ of human cancers.

Adenocarcinoma

A malignant tumor originating in ductal or glandular tissue.

Sarcoma

A malignant tumor of mesenchymal origin, such as connective tissue, muscle, or bone.

Lymphoma

A malignant tumor originating in lymphatic tissue.

Leukemia

A malignant growth of blood-forming cells.

Carcinogen

A potential cancer-causing agent.

Proto-oncogene

A normal gene that encodes components of receptor-mediated cell growth activating pathways designed to regulate normal cellular proliferation.

Oncogene

A mutant, overexpressed form of a proto-oncogene that causes gain of function and overactivity of cancer-critical genes, promoting uncontrolled cell growth.

Tumor Suppressor Gene

A gene that normally regulates the cell cycle, inhibits proliferation resulting from growth signals, stops cell division when cells are damaged, and prevents mutations; loss of function in both copies contributes to cancer.

Gatekeeper Genes

Tumor suppressor genes that directly suppress growth, including cell cycle regulator genes, checkpoint control genes, and apoptosis-related genes.

Caretaker Genes

Tumor suppressor genes responsible for maintaining overall genetic stability by encoding DNA repair proteins.

p53 Gene

The most common defective tumor suppressor gene in human cancers (missing in more than $\frac{1}{2}$ of tumors); normally accumulates after DNA damage to bind damaged DNA, stall replication, induce p21 cell cycle arrest, or trigger apoptosis/senescence.

BRCA1 and BRCA2

Breast cancer tumor suppressor genes; inherited defects in BRCA1 give women an approximate $85\%$ risk of breast cancer and a $40\%$ to $60\%$ risk of ovarian cancer, accounting for $5\%$ to $10\%$ of all breast cancer cases.

Initiation

The first step in the multistep nature of carcinogenesis, involving primary DNA damage or mutation.

Promotion

The second step in carcinogenesis, involving cell proliferation mediated by growth promoters.

Progression

The final stage of carcinogenesis, in which cells develop a fully cancerous phenotype.

Metastasis

The process by which cancer cells escape their tissue of origin using specialized enzymes and receptors, traveling through circulatory or lymphatic systems to initiate new colonies in distant sites like the lung, brain, liver, and bone.

Angiogenesis

The growth of new blood vessels, utilized by cancerous tumors to expand beyond approximately $2\,\text{mm}$ in diameter, often stimulated by tumor-produced VEGF.

VEGF (Vascular Endothelial Growth Factor)

An angiogenesis factor produced by tumor cells that stimulates the proliferation and migration of endothelial cells to orchestrate blood vessel development into the tumor.

Tumor Markers

Cell surface markers or enzymes used to identify the parent tissue of origin of new tumors and track overall tumor activity.

Grading of Cancer

The histological (microscopic) characterization of tumor cells indicating the degree of anaplasia and differentiation, ranging from Grade 1 (well differentiated) to Grade 3 or 4 (poorly or undifferentiated).

Staging of Cancer

The description of the location, size, and pattern of spread of a tumor within a host (commonly using the TNM system), evaluating factors like local growth, lymph node involvement, and distant metastases.

TNM System

An international cancer staging system based on evaluating Primary Tumor size/extent (T), regional lymph Node involvement (N), and distant Metastasis (M).

Cachexia

An effect of cancer on the body characterized by overall weight loss, skeletal muscle wasting, loss of appetite (anorexia), increased metabolic rate, and generalized weakness.

Allogeneic Bone Marrow Transplant

A procedure to rescue bone marrow following chemotherapy and radiation by reintroducing stem cells obtained from a healthy matched donor.

Autologous Bone Marrow Transplant

A procedure to reintroduce a patient's own peripheral blood stem cells back into their body after processing and storage following cancer treatment.