Neoplasia Part 1 Flashcards
what is neoplasia
- is the disordered and autonomous (uncontrolled) proliferation of NEW monoclonoal cells
- unregulated cell proliferation
- monoclonal, single genetically altered precursor cells
what does NEO mean
new
what does PLASIA mean
growth
what is benign neoplasms
- LOCAL growth
- inability to INVADE or METASTASIZE
- amenable to surgical excisions (may recur)
are benign neoplasms life threatening
no (unless significant compression of adjacent structures)
benign neoplasm are designated by the suffix
-oma
what is lipoma
-benign neoplasm of adipose tissue, common in adults 40-60 yrs old
what are the characteristics of lipoma
-soft, movable, generally innocuous, can be aesthetically unpleasant
what is fibroadenoma
-neoplasm derived form glandular and mesenchymal breast tissue
what are the characteristics of fibroadenoma
- movable, firm, painless
- “lump” often seen in women of reprodutive age
what is teratoma
- tumor derived from totipotent cells composed of all 3 germ cell components
- saccro-coccygeal or cervical in fetus/neonate
- ovarian/testicular in children/adults
a vast majority of teratoma are what
-benign, some show histologic features of malignancy
are teratomas life threatening
despite benignancy, they can pose life-threatning complications
malignant neoplasma are referred to as what
CANCER
what are the characteristics of malignant neoplasms
- able to INVADE AND DESTROY adjacent structures
- able to METASTASIZE to distant structures
- often LIFE-THREATENING
how do you treat malignant neoplasms
- require a MULTI-THERAPETUTIC approach (surgery, radiation, chemotherapy)
- key role of screening and early detection
name an example of malignant neoplasms
advanced breaks carcinoma with skin erosion and invasion into chest wall
what is the metastasic potential of malignant neoplasm
- aggressive malignant neoplasms can reach and destroy distant structures
- ex. patient with Burkitt’s lymphoma arising in the neck (cervial lymph nodes) with abdominal/:E metastases
where do benign tumor cells grow
only locally and cannot spread by invasion or metastasis
where do malignant (cancer) cells grow
-invade neighbouring tissues, enter blood vessels and metastasize to different sites
designation of neoplasms is based on what
their tissue of origin (lineage)
**neoplasms are usually composed of one cell-type of origin such as:
Epithelial (cells of skin or those lining glands/ducts of various organs)
Mesenchymal (cells in soft tissue, bone, cartilage)
Hematopoietic (cells in bone marrow and lymph nodes)
Melanocytic (melanin-producing cells of the skin)
what are exceptions to the nomenclature rule
mixed tumors
what are mixed tumors
- neoplasms composed of different cell types
- they are derived form a single cell type, but undergo divergent differentiation
ex. pleomorphic adenoma of salivary glands, Fibroadema of the breast
what are the mixed tumors we should know
- Teratoma
- Hamartoma
- Choristoma
what are teratoma
-derived from totipotent germ cells, able to differentiate into multiple recognizable (mature) tissues or more than one germ cell layer
what are hamartoma
- mass of disorganized cells native to tissue
- WRONG ARRANGEMENT
what are Choristoma
- mass of normal tissue in abnormal location
- WRONG PLACE (ectopic tissue)
what are the fundamental differences btwn benign and malignant
- degree of differentiation and anaplasia
- rate of growth
- presence of local invasion
- presence of Metastasis
what does differentiation designate
the degree to which tumors cells reflect the morphology and function of their normal counterparts
what are the characteristics of benign neoplasms
-tend to be well-differentiated and resemble their cells of origin
the degree of differentiation of malignant neoplams can range from
well to poorly differentiated or even undifferentiated
what do well-differentiated adenocarcinoma of the lung look like
-bonchoioloalveolar pattern extending through the alveolar septa
what do moderately-differentiated adenocarcinoma of the lung look like
-loss of normal architecture, retained glandular formation
what does “reversion of differentiation” describe
malignant neoplasms that lack any differentiation
–> undifferentiated cells
*what are the morphological features of malignancy
Increased N/C ratios: In normal cells (1:6), N/C of malignant cells can reach 1:1
Pleomorphism: Variation in size and shape of neoplastic cells and nuclei
Nuclear hyperchromasia: Dark nuclear staining (high color/stain)
Loss of Polarity: Loss of cellular orientation in relation to basement membrane or in relation to other cells (disordered growth)
Increased Mitotic Activity: Due to high, uncontrolled proliferation rate. Atypical mitotic forms are common
what is the rate of growth for benign tumors
GENERALLY grow slowly over months/yrs
malignant tumors have a more variable growth rate which inversely correlates with what
their level or differentiation (indolent vs. filminant course)
high growth rates can cause malignancies to “outgrow” their blood supply and lead to what
hemorrhage and necrosis
mitotic count and adjuvant studies show what
- the proliferative index of tumors
- can provide information on prognosis and response to chemotherapy
describe the local invasion of benign neoplasm
-have an expansile growth that maintains a well-demarcated boundary from the host tissue - they will not invade
some benign tumors develop a surrounding fibrous capsule whcih demaractes what
the neoplastic boundary and facilitates enucleation
malignant neoplasms have an invasive front that allow them to what
infiltrate and destroy adjacent tissues
what is one of the most reliable features of malignancy
-local invasion
what attribute defines malignancy
metastasis
what is characteristic of metastasis
-presence of tumor deposits away from primary sites
different malignancies have different
metastatic potential
what are the 3 main paths malignancies metastasize
- seeding –> tumor implantation on surfaces of body cavities
- lymphatic –> tumor spread via lymphatic system
- hematogenous –> tumor spread via vascular system
what is the most common pattern of spread in carcinomas
lymphatic spread
what happens once metastasize to lymphatics
-cancer cells invade lymph nodes, usually sentinel lymph nodes first
what pattern of spread is frequently seen in sarcomas and some carincomas (renal, hepatocellylar, thryoid and choriocarcinoma)
-hematogenous spread
why are liver and lung more often affected by hematogenous spread
-they receive all portal and caval blood flow
what is cancer epidemiology
Studies the distribution and patterns of cancer in populations, focusing on influencing factors and trends to better understand causes and prevention
what is the 2nd leading cause of death in the US in both adults and children
cancer
what are the most common cancer by incidence
- breast/prostate
- lung
- colorectal
what are the most common causes of cancer death
- lung
- breast/prostate
- colorectal
what factors affect cancer epidemiology
Geographic
Environmental –> Environmental carcinogens
Age
Heredity
what are the important types of carcinogens
Chemical
Viral/Bacterial
Radiation
see slide 49
see slide 49
Epstein-Barr virus is a member of what family
Herpes
what is EBV associated with
various B-cell neoplasms and nasopharyngela carcinoma (epithelial)
what do EBV genes promote
proliferation and expansion of cells while decreasing their rate of apoptosis (death
what are the main 2 types of radiation
- ionizing (nuclear receptor accidents and radiotherapy)
2. nonionizing (UVB rays)
what are the 3 types of genetic predispostion in cancer
- autosomal dominant cancer cyndromes (Rb, BRCA1 and 2, APC)
- autosomal Recessive defects in DNA repair (Xeroderma Pigmentosa, Ataxia-telangentasia)
- Cancers of uncertain inheritance (not well understood, early onset of cancer clustered in families)
cancer incidence and death rate increase with what
age
what is associated with the increased incidence of cancer and age
-accumulation of somatic mutations and decreased immune competency contribute to this trend
