• Neo = New ; Plasia= growth
• Abnormal mass of tissue as a result of abnormal growth
or multiplication of cell.
• Growth of neoplastic cell persist in excessive manner
even after the stimulus that evoked the changes stop.
CLASSIFICATION OF NEOPLASIA
2 types :
- Suffix = –oma to cell type which the tumor arise
- Eg: fibrous tissue – fibroma
Bone tissue – Osteoma etc.
- Suffix: –Sarcoma =
Malignant tumor (Cancer) that arises from
transformed cells of mesenchymal origin
–Carcinoma= Malignant tumor from epithelial origin
- Microscopic and gross characteristic relatively inoncent - Invade and destroyed adjacent structure and spread to distant
- Remain localized • Will invade other neighbouring tissues & m etastasize (Lymph &
- Amendable to local surgical removal • Lower prognosis than benign tumors
MALIGNANT AND BENIGN
TYPE BENIGN MALIGNANT
- Well differentiated
- Closely resemble their normal
- Mitosis usually rare
- Nuclei remain at basal layer
but usually enlarged.
- Poor differentiate@anaplastic
- Loss of structure and function
- Plemorphism, hyperchromatic,
ration, giant cell.
- Mitosis often numerous.
- Loss of polarity
- Remain localized at site of
- Does not have the capacity
to infiltrate,invade or
- Grow by progressive
destraction and penetration of
- Do not develop well of define
- Hemmorhage and necrosis.
METASTASIS - Absent - Metastasize
- Factor increase of metastasis
• Larger of tumor
• Older of tumor
• Poorly differentiated
- Disseminate by 3 pathways
• Seeding body cavity
• Lymphatic spread
• Hematogenous spread
History and physical
What the health care worker learns from talking to the patient and
through direct examination may give clues to the presence of a
neoplasm. Signs and symptoms such as weight loss, fatigue, and
pain may be present. A mass may be palpable or visible.
The use of plain films (x-rays), computed tomography (CT),
magnetic resonance imaging (MRI), mammography, and
ultrasonography (US) may be very helpful to detect the presence
and location of mass lesions. The findings from these methods
may aid in staging and determination of therapy.
Genetic markers include chromosomal alterations (translocations,
deletions, duplication, etc.); specific gene defects; single
nucleotide polymorphisms, and gene rearrangements. Detection
of specific genes (such as BRCA-1 for breast cancer) may
suggest an increased risk for some malignancies.
Cytology Methods that sample cells can be simple and cost-effective and
minimally invasive. A good example is the Pap smear for diagnosis of
cervical dysplasias and neoplasms. Cells exfoliated into body fluids may
also be examined. Fine needle aspiration (FNA) can be used to sample a
variety of mass lesions.
Methods that sample small pieces of tissue (biopsy) from a particular
site, often via endoscopic techniques (such as colonoscopy, upper
endoscopy, or bronchoscopy) can often yield a specific diagnosis of
malignancy. At surgery, portions of an organ or tissue can be sampled, or
the diseased tissue(s) removed and examined in surgical pathology to
determine the stage and grade of the neoplasm.
Autopsy Sometimes neoplasms are not detected or completely diagnosed during
life. The autopsy serves as a means of quality assurance for clinical
diagnostic methods, as a way of confirming diagnoses helpful in
establishing risks for family members, as a means for gathering statistics
for decision making about how to approach diagnosis and treatment of
neoplasms, and to provide material for future research.
General findings such as anemia, enzyme abnormalities (such as an
increased alkaline phosphatase), and hematuria or positive stool
occult blood are helpful to suggest further workup. Tumor markers in
serum such as carcinoembryonic antigen (CEA), alpha-fetoprotein
(AFP), or human chorionic gonadotropin (HCG) can be performed.
Unfortunately, they are not all that specific or sensitive, particularly
when applied as screening tests to a general population. More specific
testing, such as measurement of prostate specific antigen (PSA)
levels, may help to determine the presence of specific neoplasms, but
such tests are not perfect screening tools in a general population.
Spread of tumour:
Direct spread Distant spread
-means tumour spreading and involving the
tissues around the tumour.
- As example,if the primary tumours arises
from the bronchus,this tumour can spread
to the lung tissue.
-means the tumour from one site (primary)
is now transferred to a distant site
-This process called metastasis.
-There are three ways on how tumour can
metastasise to distant sites. (refer table in
By Invasion of
-Lymphatic are channels lined by endothelium-drain lymph from
tissues to lymph nodes (regional lymphnodes)
-Ex : Breast carcinoma-enlarged axillary lymph nodes
-Usually cancers that spread via lymphatic are *CARCINOMAS.
-Spread via blood channels.
-VEINS are more frequently invaded than arteries because:
c-slower blood flow
-Neoplasm that spread via blood channels usually *SARCOMAS
Through body cavity It can either spread via:
-tumours seeding over surfaces in peritoneal,pleural and
-Ex:Carcinoma in ovary of one side spreading to the other ovary
or to other organs in peritoneum
2-Cerebral spinal fluid
-occurs for cancers in the brain and spinal cord.
• Made by Pathologist
• Microscopic appearance
• Assesment depends on :
Nuclear size &
• Degree of diff. indicates :
Grading of Malignant Neoplasms
I Well differentiated
III Poorly differentiated
IV Nearly anaplastic
• Made by Surgeon
• Gross anatomical appearance
Eg : lung carcinoma
Staging of Malignant Neoplasms
Tis In situ, non-invasive
T Refers to Primary tumors
Small, minimally invasive within primary
Larger, more invasive within the primary
Larger and/or invasive beyond margins of
primary organ site
Very large and/or very invasive, spread to
N Refers to Lymph Nodes
N0 No lymph node involvement
N1 Nearby lymph node involvement
N2 Regional lymph node involvement
N3 More distant lymph node involvement
M Refers to anatomical distance metastases
M0 No distant metastases
M1 Distant metastases present
Although benign tumours are confined
to their site of origin, they may cause
clinical problems due to:
Pressure on adjacent tissues
(e.g. benign meningeal tumours
Obstruction to the flow of fluid
(e.g. benign epithelial tumour
blocking a duct)
Production of a hormone (e.g.
benign thyroid tumour causing
Transformation into a
malignant neoplasm (e.g.
adenormatous polyp progressing
to an adenocarcinoma)
Morbidity and mortality associated with
Pressure on and destruction of
Formation of secondary tumours
Blood loss from ulcerated
Obstruction of flow (e.g.
malignant tumour of the colon
causing intestinal obstruction)
Production of a hormone (e.g.
ACTH and ADH from some lung
Other paraneoplastic effects
causing weight loss and debility
Cachexia (wasting syndrome)
• Progressive loss of body fat and lean body mass
accompanied by profound weakness, anorexia, and
• The origins of cancer cachexia are obscure.
• Cachexia is not caused by the nutritional demands of the
• Results from the action of soluble factors such as
cytokines produced by the tumor or host
• Cachexia- the loss of
• Symptoms complexes in cancer-bearing
patients that cannot be explained by :-
• local or metastatic spread
• elaboration of hormones indigenous to tissue
• May represent early manifestations of tumor
• May represent significant clinical problems
• May even be fatal
• Occurs in about. in 10% of patients with cancer
• They are syndromes involving nonmetastatic
systemic effects that accompany malignant
Syndrome Mechanism Example
Secretion of ACTH-
Lung small cell anaplastic
(oat cell) carcinoma
Lung (squamous cell)
Lung small cell anaplastic
(oat cell) carcinoma
Renal cell carcinoma
Hypercoagulable state Various carcinomas
Hypoglycemia Insulin-like substance
Various carcinomas and
indoleacetic acid (5-
• From team Omega
It is a process by which normal cells are transformed into cancer cells
Malfunction Of MYC Gene
Carcinogenesis:Amultiple step process
• Carcinogenesis= A multistep process resulting from the accumulation of
multiple genetic alteration , give rise to transform phenotype .
• Mutation provide cells of precursor lesion with a selective advantage
(Darwinin Selection) . Once initiate, cancer continue undergoes darwinian
• Over period of time, tumors become more aggressive and acquire greater
malignant potential (Tumor Progression, not represent simply by an
increase in tumor size) .
•Some mutation may lethal. Others may spur cell growth by affecting proto-oncogenes or
cancer suppressor genes.
Hallmarks of cancer
• Self sufficiency in growth signals
• Insensitivity to growth inhibitory signals
• Evasion (Immortalization) of cell death
• Limitless replicative potential
• Development of sustained angiogenesis
• Ability to invade and metastasize
SELF SUFFICIENCY IN GROWTH FACTORS
Normal cells require growth stimulation by growth factors to undergo proliferation.
•Many cancer cells acquire growth self-sufficiency by acquiring ability to synthesize the
same growth factors which they are responsive.
•Another mechanism by which cancer cells acquire growth self-sufficiency is by
interaction with stroma. In some cases, tumor cells send signals to activate normal cells in
the supporting stroma which in turn produce growth factors that promote tumor growth .
2. Growth factor receptors and non-Receptor Tyrosine Kinases
•Mutant receptor proteins deliver continuous mitogenic signals to cells even in the absent
of growth factor in the environment .
•Mutation is overexpression of growth factor to level which growth factor receptor which
render cancer cells hyperresponsive to level of the growth factor that would not normally
•Most commonly mutated proto-oncogene in human tumor.
•Normal RAS protein flip back and forth between an excited signal-transmitting state and not active
•Activated RAS stimulates downstream regulators of proliferation by two distinct pathway that
converge on the nucleus and flood it with signal for cell proliferation.
•Mutational activation of these massengers to the nucleus can mimic growth promoting effect of
activation RAS .
•Activating mutation RAS as well as it downstream signaling molecules are very common in wide
variety of tumor .
•Also mutation in RAS mimicked by loss-of—function mutations in the GTPase-activating
proteins with a failure to stimulate GTP hydrolysis and thereby restrain normal RAS protein.
INSENSITIVITYTO GROWTH INHIBITORYSIGNALS
• Products of tumor suppresor genes apply brakes to cell proliferation. Disruption of such
genes renders cells refractory to growth inhibition and mimics the growth-promoting
effect on oncogenes .
RB GENES: Governor of the cell cycle
o RB gene product is a DNA-binding protein that expressed in every cell type examined ,
exists in active hypophosphorylated state and an inactive hyperphosphorylated stated.
o RB exerts antiproliferative effect by controlling regulations of G1/S checkpoint (mitosis
cycle) , the portal through which cell must pass before DNA replication commences .
o RB in active form, hypophosphorylation bind to E2F transcription factors. This
interaction prevents transcription of genes like cyclin E that are needed for DNA
replication, and so the cell arrested in G1.
o Growth factor signaling leads to cyclin D expression, activation of the cyclin D-CDK4/6
complexes, inactivation of RB by phosphorylation , and thus release E2F .
o Loss of cell cycle control is fundamental to malignant transformation.
o All cancers have disabled G1 checkpoint due to mutation either RB or genes that affect
RB function such as cyclin D, CDK4, and CDKIs
TP53 GENE: Guardian of the genome
• The p53-encoding tumor suppressor gene, TP53 , one of the most commonly mutated
genes in human cancers.
• The p53 proteins prevents neoplastic transformation by three interlocking mechanisms :
• Activation of temporary cell cycle arrest (quiescence ) when DNA damage and assist DNA repair
• Induction of permanent cell cycle arrest (Senescence) when DNA damage genes cannot be
• Or triggering of programmed death (apoptosis)
• Rb sense external signal, p53 is central monitor of internal stress, directing stress to one
of the three mechanism .
• Example of stresses that trigger the p53 responses pathway including anoxia,
inappropriate oncoprotein activity and damage to integrity of DNA .
= The condition or process of deterioration with age.
• Metastatic cascade subdivided into :
Invasion of ECM
Vascular dissemination and homing of tumor
• 2 types of ECM :
basement membrane both are composed
Interstitial connective tissue of collagen, glycoprotein
Loosening of intracellular junctions occurred because
of E-cadherin lost its function (keep cells together &
transmit antigrowth signal) by :
• mutational inactivation of E-cadherin gene
• activation of β-catenin gene
(regulating the coordination of cell–cell adhesion and gene
• inappropriate expression of SNAIL & TWIST
transcription factors (Give Metastatic Ability)
Degradation of basement membrane & interstitial
Tumor cells secrete proteolytic enzymes / induce stromal
cells elaborate proteases (cathepsin D, urokinase
plasminogen activator, MMPs) tumor cell invasion
remodel insoluble components of
basement membrane & interstitial
matrix + release ECM-sequestered GF
Changes in attachment of tumor cells to ECM
Loss in adhesion in normal cells apoptosis ; but
tumor cells are resistant to apoptosis, instead caused
matrix modification by cleaving of basement membrane
proteins (collagen IV, laminin) by MMP generates
novel sites (bind to tumor cells’ receptors) migration
Migration is directed by tumor cell-derived cytokines
(autocrine motility factors) + cleaved products (collagen &
laminin) + some growth factors + stormal cells (HGF/SCF)
• In circulation, tumor cells vulnerable to destruction by host immune cells – it will form emboli & adhere to
the circulating leukocytes = protection
• Site of extravasation & the organ distribution of metastases based on location of primary tumor and its
vascular or lymphatic drainage. This tropism influences by :
i. Expression of adhesion molecules by tumor cells are preferential to the ligand on endothelium of
ii. Expression of chemokines (participate in chemotaxis of leukocytes) & their receptors – tumor cells use
similar tricks to home in on tissue
iii. When reach the target colonize the site (tumor cells dependent on a receptive stroma for growth)
• Tumor cells are inefficient in colonizing of distant organs and concept of dormancy refer to prolonged
survival of micrometastases w/o progression
Etiology of cancer: carcinogenic events
• Chemical carcinogens
• Radiation carcinogens
• Viral and microbial oncogenesis
Direct-acting agents Indirect-acting agents
• Does not require metabolic
conversion to become carcinogenic
• Require metabolic conversion to
become active carcinogenic
• Weak carcinogens • E.g: polycyclic hydrocarbons,
aromatic amines, azo dyes
• E.g: alkylating agents
Chemical carcinogens and the tumours
with which they are associated:
Chemical Tumor Comments
Polycyclic hydrocarbon Lung cancer Present on fossil fuels
Aromatic amines Skin cancer
Rubber and dye workers
Nitrosamines Gut cancer Proven in animals
Azo dyes Bladder n liver cancer Proven in animals
Leukemia Small risk in human
Other organic chemicals
e.g: vinyl chloride
Liver angiosarcoma PVC manufactures
Arsenic compounds Skin cancer No longer a common
UV light, x rays, nuclear fission
• Ionizing radiation
- cause chromosome breakage, translocation, less
frequency, point mutation
- Lead to genetic damage n carcinogenesis
- E.g: chronic lymphocytic leukemia , Thyroid carcinoma
• UV radiation
- Damage DNA by forming pyrimidine dimer
- Cause skin cancer (melanoma, SCC, BCC)
- Risk factor: fair-skinned people
- May cause the mutational activation of an oncogen (RAS)
- non-mutagenic, non-tumorigenic
- Induces cell proliferation
- E.g: phorbol esters, hormones, phenols, certain drugs
Cancer Progression Due To Constant Irritation
• Autosomal recessive
• Defects in NER genes = (DNA repair mechanism )
• Due to inability to repair DNA damage induced by UV
• 200 X increase risk of skin cancer
VIRAL and MICROBIAL
•Cause by Retrovirus: Human T Cell Lymphotropic Virus-1
•a/w T cell leukemia/lymphoma
•Has tropism for CD4 Tcells target for neoplastic
•Transmission: sexual intercourse, blood products or
• Human papilloma virus
• Epstein-Barr virus
• Hepatitis B virus
• Kaposi Sarcoma herpes virus