This document defines neoplasia and describes the characteristics and classification of tumors. It discusses the components of tumors, benign and malignant tumor nomenclature, criteria to differentiate benign from malignant neoplasms including clinical features, growth rate, microscopy, invasion and metastasis. It also covers tumor markers, immunohistochemistry and cytology methods.

1. NEOPLASIA

2. • Neoplasm – New growth
Neoplasm – Definition by Willis.
“A neoplasm is an abnormal mass of
tissue, the growth of which is purposeless
and 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”.
Study of neoplasms is called oncology

3. Components of tumours
(i) Parenchyma – neoplastic cells
(ii) Supporting stroma- (Connective tissue
and vessels)
Frame work Blood supply

4. Nomenclature
•Benign tumour
Cell of origin + -oma
Mesenchymal tumours – fibroma
chondroma, osteoma.
Benign epithelial tumours – name based on cell
of origin, microscopic pattern or on gross
appearance.
Eg: Adenomas, Papillomas, Cystadenomas,
Papillary cystadenomas.

5. Malignant tumours
•Mesenchymal – Sarcomas
(Rhabdomyosarcoma, leiomyosarcoma)
•Epithelial – Carcinomas
( Adenocarcinoma, Squamous
cell carcinoma)

6. Teratoma
Made up of a variety of parenchymal cell
types representative of more than one germ
layer – usually all three germ layers – seen in
gonads.
Mature cystic teratoma (Dermoid cyst) of
ovary
Mature (Benign)
Teratoma
Immature (Malignant)

7. Choristoma - Ectopic rest of normal tissue
(Heterotopia)
Eg: Adrenal cells under the renal capsule, Pancreatic
tissue in small intestine /Stomach.
Hamartoma – Mass of disorganised but
mature specialised cells or tissues
indigenous to the site.
Eg: Pulmonary hamartoma, Benign behaviour

9. General criteria to differentiate benign &
malignant neoplasms
I Clinical features
II Gross appearance
III Rate of growth
IV Microscopy – Differentiation & anaplasia
V Local invasion
VI Metastasis.

10. I. Clinical features
•Benign * Malignant
Generally slow growing Rapid growth
Symptoms depend on Ulcerate
Location Locally invade
Distant spread
Systemic features
(Wt. loss, Anaemia)

11. II. Gross appearance
• May not be diagnostic
•Benign * Malignant
Spherical / ovoid Irregular
Encapsulated/ Poorly encapsulated
Well circumscribed Adherent to surrounding
Freely movable C/s secondary changes
C/s uniform Sarcomas – fleshy.

12. III Rate of growth
•Generally – benign – slow Malignant –
Rapid Erratic
Growth of neoplasms influenced by:
- Hormone dependance eg: leiomyoma uterus
- Blood supply
- Growth factors by tumour cells
(EGF, FGF, PDGF, CSF, TGF/3, IL0
- Differentiation.

13. III Microscopy
Important in recognising and classifying tumours
Pattern of growth
Epithelial – Acini, Sheets, cords, papillary
Mesenchymal – Interlacing bundles, whorls
Intercellular matrix +
Mixed pattern – Teratoma, pleomorphic adenoma
Carcinosarcoma
Haemopoietic – Little stroma
(lymphoma /leukaemia)
Benign – Resemble normal tissue.

14. Differentiation & Anaplasia
Differentiation - Extent to which the tumour cells
resemble the parent cell morphologically &
functionally
Minimal deviation- Well differentiated
Poor resemblance- Poorly / undifferentiated.
Anaplasia: Lack of differentiation
(hall mark of malignancy)
Causes morphological and functional alteration.

15. 1 Structural 2. Functional abnormalities
Hyperchromatism. 3.Chromosomal abnormalities
Pleomorphism (Philadelphia chromosome)
High N:C ratio
Anisonucleosis
Nucleolar changes
Normal
Mitotic figures
Atypical
Tumour giant cells
Loss of polarity

16. Dysplasia:-
Disorderly, but neoplastic proliferation
-Pleomorphism
- Mitotic activity
- Architectural anarchy
Carcinoma in situ – full thickness
- Dysplasia does not indicate cancer / do not
necessarily progress to cancer.
Eg:- Cervical dysplasia
Bronchial epithelial dysplasia – smokers
Barret oesophagus.

17. Metastasis (Most reliable differentiating
feature)
Tumour implants discontinuous with primary
Reduces possibility of cure
Exceptions – gliomas
Basal cell carcinoma.

18. Lymphatic spread
• Mostly seen in carcinomas
• Some sarcomas can have lymphatic spread
• Angiosarcoma, rhabdomyosarcoma, clear cell sarcoma, epithelioid
sarcoma, synovial sarcoma

19. II. Haematogenous spread
Typical of sarcoma
Arteries rarely penetrated
Venous invasion – flow venous drainage
Portal area flow liver
Caval blood lungs
Paravertebral plexus vertebral bodies
Unfavourable – spleen, heart, sk. Muscle
Gross- Multiple, scattered, rounded mass
Ca with hematogenous spread: RCC, HCC

20. III Seeding of body cavities and natural passages.
Eg: Peritoneal, pleural, pericardial
( Transcoelonic spread)
Eg: Krukenberg tumour
Peritoneal involvement of carcinoma ovary
Pseudomyxoma peritonei.
Preferential sites of systemic involvement
Prostatic – bone
Bronchogenic – Adrenals, brain.
Neuroblastomas – Liver, bone.

21. Cell cycle and control mechanisms
• G1 : Pre-synthetic phase
• S : Synthetic phase (DNA synthesis)
• G2 : Post-synthetic phase
• M : Mitotic phase: Cells divide and produce new cells
• G0 : Quiescent state: Cells in this state remain
quiescent for variable periods, but can be recruited in
cell cycle if stimulated later

22. G0

23. Regulation of cell cycle
• RB
• Molecular on/off switch
• Governor of the cell
• P53
• Molecular policeman
• Guardian of the genome

24. • During the G1 phase of the cell cycle, cyclin D binds to and activates
CDK4, forming a cyclin D-CDK4 complex.
• This complex has a critical role in the cell cycle by phosphorylating the
retinoblastoma susceptibility protein (RB).
• The phosphorylation of RB is a molecular ON-OFF switch for the cell
cycle
• In its hypophosphorylated state, RB prevents cells from replicating by
forming a tight, inactive complex with the transcription factor E2F

25. • Phosphorylation of RB dissociates the complex and results in
activation of E2F.
• Activated E2F results in transcription of target genes essential for
progression through the S phase
• These include cyclin E, DNA polymerases, thymidine kinase,
dihydrofolate reductase.

27. Role of p53
ATM gene
ATR gene
DNA damage
sensors
P53
MDM2
P
P53
released

28. p53
P21 GADD45 BAK
BAX
PUMA
Micro RNA
Long non coding
RNA
Arrest G1-S
transition
Arrest G2-M
transition
Apoptosis Senescence of cell
Mir-34 causes DNA
repair

29. • ATM and ATR gene acts as DNA damage sensors
• When DNA damage is detected, p53 is phosphorylated to release the
MDM-2
• Released p53 activates p21, GADD45, BAK, BAX, PUMA and micro
RNA/long non coding RNA

30. Cell cycle inhibitors

31. Cellular and molecular hallmarks of cancer
• Sell sufficiency in growth signals: due to oncogenes
• Insensitivity to growth inhibitor signals: tumor suppressor genes
• Evasion of apoptosis
• Limitless replicative potential
• Angiogenesis
• Invasion and metastasis
• Ability to escape immune recognition and regulation
• Altered cellular metabolism (by aerobic glycolysis/ Warburg effect)

32. Protooncogenes and oncogenes
• Proto-oncogenes are normal genes required for cell proliferation and
differentiation
• Mutation causes proto-oncogenes to oncogenes
• Oncogenes are genes responsible for causing dedifferentiation and
cancer
• There are five groups of oncogenes

33. Growth factor
Growth factor receptor
Cyclins and cyclin dependent
kinases
Signal transduction
proteins
Nuclear transcription
factors
G1-S-G2-M
Cell proliferation

34. ONCOGENES
Growth factor
TGF alpha Astrocytoma
PDGF beta Astrocytoma
HGF Hepatocellular carcinoma
FGF Osteosarcoma, breast cancer
Growth factor receptor
FLT-3 Leukaemia
ALK Inflammatory myofibroblastic tumor, anaplastic large cell
lymphoma
KIT Gastrointestinal stromal tumor, seminoma
RET Medullary carcinoma thyroid
PDGFR Glioma
EGFR Lung adenocarcinoma

35. Signal transduction factors
BRAF Melanoma, hairy cell leukaemia, papillary carcinoma
thyroid, LCH, pilocytic astrocytoma, PXA, Epithelioid GBM
GTP binding proteins
KRAS Colon, lung and pancreas adenocarcinoma
NRAS Melanoma
HRAS Bladder cancer
GNAS Pituitary adenoma, fibrous dysplasia
GNAQ Uveal melanoma
ABL CML, ALL
NOTCH T cell lymphoma
JAK-2 Polycythemia vera, essential thrombocythemia,
myelofibrosis

36. Nuclear transcription factors
NF-KB Diffuse large B cell lymphoma
E2F SCC, oral
C-MYC Burkitt lymphoma
N-MYC Neuroblastoma
L-MYC Small cell carcinoma lung
Cyclins and cyclin dependent kinases
Cyclin D1 Mantle cell lymphoma, high grade endometrial stromal
sarcoma
Cyclin dependent kinases Glioblastoma multiforme, liposarcoma

37. Oncogene addiction
• Coined by Dr. Bernard Weinstein
• It’s a phenomenon where some tumors are dependent on a single
oncogenic protein for sustained growth and proliferation
• Inhibition of specific oncogene is sufficient to halt the neoplastic
process
• CML is the best example for oncogene addiction

38. Tumor suppressor genes
• Tumor suppressor genes apply brakes to cell proliferation and
abnormalities in these genes lead to growth inhibition and
carcinogenesis
• Both alleles of a tumor suppressor gene must be mutated for
carcinogenesis to occur because heterozygous cells have adequate
tumor suppressor activity
• Mutation of second normal tumor suppressor leading to
carcinogenesis is called loss of heterozygosity

39. Tumor suppressor genes
Mitotic signalling pathway inhibitors
APC WNT signalling pathway Carcinoma of stomach, colon, pancreas
and melanoma
NF-1 (Neurofibromin-1) RAS/MAPK signalling inhibitor Neuroblastoma, JMML
NF-2 (Merlin) Hippo pathway meningioma, schwannoma
PTCH Hedgehog pathway Gorlin syndrome: basal cell carcinoma,
medulloblastoma
SMAD2 and SMAD4 TGF B signalling Colon and pancreatic cancers
PTEN PIK/AKT signalling Cowden syndrome- breast cancer,
endometrial cancer and thyroid cancer
Cell cycle progression inhibitors
CDKN2A P16 inhibits CDK
P14 activates p53
Melanoma, carcinoma of pancreas,
breast and esophagus
RB Inhibitor of G1-S Retinoblastoma, osteosarcoma
Angiogenesis inhibitors
VHL Inhibitor of HIF-1a Cerebellar hemangioblastoma, retinal
angioma, clear cell RCC
SDH B/D Paraganglioma, phaeochromocytoma

40. Invasion of invasion and metastasis
CDH-1 (E- Cadherin) Gastric carcinoma, lobular breast
carcinoma
Genomic stability enabler
p53 Cell cycle arrest Li fraumeni syndrome
DNA repair factor
BRCA1 & 2 Familial breast cancer
MSH2, MLH1, MSH6 DNA mismatch repair HNPCC

41. Paraneoplastic syndromes
• Symptom complexes that cannot be explained by tumor spread or
release of hormones that are indigenous to the tumor
• It is seen in 10% of the persons with cancers
• Hypercalcemia- most common PNS
• Most common cancer associated with hypercalcemia- breast cancers
• Among the lung cancers- squamous cell carcinoma
• It is due to parathyroid hormone related peptides

42. Paraneoplastic syndrome
Endocrinopathies
Hypercalcemia (due to PTHrP, PGE2, 1,25-DHCC) Squamous cell carcinoma of the lung
Breast carcinoma
Renal cell carcinoma
Cushing syndrome Small cell carcinoma lung
Carcinoid lung
Syndrome of inappropriate secretion of ADH Small cell carcinoma of lung
Hypoglycemia Fibrosarcoma
Insulinoma
Hepatocellular carcinoma
Solitary fibrous tumor
Hematological
Polycythemia Renal cell carcinoma
Hepatocellular carcinoma
Cerebellar hemangioblastoma
Pheochromocytoma, leiomyoma
Trousseau syndrome (Migratory superficial thrombophlebitis) Adenocarcinoma of pancreas, prostate and lung
Non bacterial thrombotic endocarditis Pancreatic adenocarcinoma, AML-M3

43. Dermatological diseases
Acanthosis nigricans Gastric adenocarcinoma, lung and uterine cancer
Dermatomyositis and polymyositis Breast, lung and colorectal cancer
Leser trelat sign (sudden multiple seborrhoeic
keratosis)
Gastrointestinal adenocarcinoma eg stomach, liver, colorectal,
pancreas, breast and lung
Neuromuscular
Myasthenia gravis (antibodies against post synaptic
acetyl choline receptors)
Thymoma
Lambert eaton syndrome (antibodies against pre
synaptic P/Q type calcium channels at neuromuscular
junction)
Small cell carcinoma
Opsoclonus myoclonus ataxia syndrome (autoimmune
reaction against RNA binding protein Nova 1
Neuroblastoma
Small cell carcinoma
Paraneoplastic cerebellar degeneration (antibodies
against Hu, Yo and Tr antigens in purkinje cells)
Small cell carcinoma, gynaecological and breast cancers, hodgkins
lymphoma
Paraneoplastic encephalitis (antibodies against Hu
antigens in neuron)
Small cell carcinoma lung

44. Tumor markers
• Substances found in blood, urine or body tissues elevated in cancer
• Produced directly by tumor or non tumor cells in response to tumor
• Plays an important role in diagnosis, prognosis, screening of tumor,
effect of treatment, recurrence of tumor, tumor resistance)
• Tumor never used for confirmation of diagnosis
• Tumor markers can also be detected by immunohistochemistry

45. Tumor markers Tumor
Calcitonin Medullary carcinoma thyroid
CEA Colon, pancreas, lung, breast, stomach and heart
CA-125 Ovarian cancers
CA 19-9 Colon, pancreatic and breast
CA15-3 Breast cancer
CA27-29 Breast cancer
CA72-4 Gastric ovarian and pancreatic
PLAP, C-KIT Dysgerminoma
AFP Yolk sac tumor
Beta hcg Choriocarcinoma
5 hydroxyl indole acetic acid Carcinoid
Vanillyl mandelic acid Pheochromocytoma, neuroblastoma

46. Immunohistochemistry
• It is a technique to detect surface markers on the surface of tumor
cell using specific antibodies with a coloured marker
• It determines the histogenesis of the tumor
• Detection of molecules that have prognostic/therapeutic significance
eg ER/PR/Her2neu
• Used in diagnosis of tumor

47. IHC Tumor
HMB-45 Melanoma
CD99 Ewing sarcoma
CD10 Follicular lymphoma, low grade endometrial stromal sarcoma
CD117 Seminoma, GIST
CD34 Angiosarcoma
S100 Melanoma, Schwannoma
GCDFP Breast cancer
TTF-1 Lung cancer, all thyroid cancer except anaplastic carcinoma
ALK Anaplastic large cell lymphoma, inflammatory myofibroblastic tumor
PAX8 Pan renal thyroid and mullerian marker
PAX5 B cell neoplasm marker
CD30, CD15 Hodgkin lymphoma, CD30 0nly in embryonal carcinoma

48. Cytology methods
• Two types
• Fine needle aspiration cytology
• Exofoliative cytology

49. Fine needle aspiration cytology
• It involves aspiration of cells from tumor masses
• Uses 22-27 gauge needle
• For vascular tissues like lymph node 27 gauge needle is used
• Contraindications
• Bleeding diasthesis
• Uncooperative patient
• Skin infection at the area of FNAC
• Increased risk of anaphylactic reaction such as aspirating hydatid cyst
• FNAC not useful to differentiate follicular adenoma from follicular
carcinoma

50. Exfoliative cytology
• Used for cervical, endometrial, stomach and bronchus tumors
• Most commonly used in cervical smears
• Uses Ayres spatula and cervical brush
• For screening of cancers
• Material is put into coplin jar containing 95% ethanol
• Stained using papanicolov stain
• Detects dysplasia to malignancy
• Two preparations- conventional and liquid based cytology (LBC)
• Two types of LBC- Thin prep and sure path

51. Metastasis
• The process by which cancer cells spreads from the primary organ to
distant locations of the body
• Metastasis is a sign of malignancy
• Metastasis is controlled by metastasis signature genes and metastasis
suppressor genes
Metastasis signature genes Metastasis suppressor genes
Ezrin (seen in RMS and osteosarcoma) Mir 226, Mir-335
Mir-10b NM23
SNAIL KAI-1 (prostate cancer)
TWIST KiSS (malignant melanoma)

52. Steps of metastasis
• Detachment of tumor cells
• ECM degradation
• ECM attachment
• Migration, vascular dissemination and homing of tumor cells

53. Detachment of tumor cells
• First step in metastasis
• Normally two cells adhere to each other using adhesion molecules
like E-cadherin
• During cancer, there is mutation of E-cadherin and loss of E-cadherin
• Tumor cells discohese from each other
• Loss of E-cadherin seen in lobular carcinoma breast and signet ring
cell adenocarcinoma stomach

54. Extracellular matrix degradation
• ECM degradation is required for migration of tumor cells
• It is the digestion of epithelial and vascular basement membrane
• This is carried out with the help of certain enzymes
• Enzymes are
• 1. Matrix metalloproteinase (MMP-2 &MMP-9)
• 2. Cathepsin D
• 3. Urokinase plasminogen activator
• Proteases are secreted by tumor cells, macrophage and fibroblasts
• MMP-9 has an additional function of angiogenesis with the help of
VEGF

55. Extracellular matrix attachment
• Tumor cells express integrins to attach to ECM components
• The components to which cells attach are
• 1. Collagen
• 2. Laminin
• 3. Fibronectin
• 4. Vitronectin

56. Migration, vascular dissemination and homing
• Tumor cells migrate into the blood vessels from the extracellular matrix
• Tumor cells form emboli with platelets and leucocytes and migrate to
distant organs
• When it reaches distant organs, it extravasates through the endothelial
spaces to reach the organ
• Tumor cells have certain adhesion molecules on their surface like CD44
which binds to hyaluronic acid on high endothelial venules and extravasate
into lymph node
• Breast cancer cells express CXCR4 and CCR7 which helps in tumor cell
extravasation

58. Warburg effect- aerobic glycolysis
• Even in the presence of sufficient oxygen, cancer cells glycolysis for
energy generation rather than the more efficient mitochondrial
oxidatative phosphorylation
• ATP is produced at a faster rate through glycolysis than through
oxidative phosphorylation
• Production of lactate to glucose occurs 10-100 times faster than
complete oxidation of glucose in mitochondria

59. Epigenetic change
• It is process of silencing of DNA
• No structural aberrations are produced in the DNA
• There is no insertion or deletion of DNA
• Some chemical groups are added such as DNA methylation and
histone acetylation
• Such addition of chemical groups silences DNA and DNA not
expressed
• Cancers can be caused by silencing of tumor suppressing genes
• Epigenetics have a role in drug resistance and sensitivity

60. Examples of epigenetics
Gene Method of epigenetic modification Malignant tumor
DNMT3A DNA methylation AML
MLL1 Histone methylation Acute leukaemia
cREBBP/ EP300 Histone acetylation DLBCL

61. Chromothrypsis
• Dramatic chromosomal catastrophe
• Literally means chromosomal shattering
• Chromosomes breaks and shatters followed by hapahazard repair
• This activity will activate oncogenes and inactivate tumor suppressor
genes
• Seen in osteosarcoma and glioma

62. Cancer cachexia
• It is the loss of body fat and protein seen in chronic cancer patients
• Results in wasting of muscles
• Most common cytokine involved is TNF-alpha
• It is due to excessive activation of ubiquitin proteasome pathway

63. Radiation carcinogenesis
• Caused by ultraviolet radiation and ionizing radiation
• Ultraviolet radiation
• UV rays can be divided into three wavelength rays
• UV-A (320-400nm)
• UV-B (280-320nm)
• UV-C (200-280nm)
• UV-B is the most carcinogenic due to formation of pyrimidine dimers
• UV rays are associated with increased risk of basal cell carcinoma,
squamous cell carcinoma, melanoma
• Most common carcinoma is basal cell carcinoma
• Melanoma is associated with intense intermittent exposure like sunbathing

64. Ionizing radiation
• Radiation from electromagnetic (X rays) and particulate (alpha and
beta particles)
• Ionizing radiation induces DNA mutations to cause cancer
• Most common malignancies are ANL and papillary carcinoma thyroid
• All leukaemias are associated with malignancy except CLL
• Skin, bone and gut are least susceptible to radiation carcinogenesis

65. Chemical carcinogenesis
• It’s a process in which chemicals induces carcinogenesis
• There are two types of chemicals
• Direct acting agents- do not require metabolic conversion to cause
DNA mutation eg alkylating agents
• Indirect acting agents- its first converted into a carcinogen by
cytochrome p450. eg benzopyrene and polycyclic hydrocarbons

66. Chemical carcinogenesis includes three steps
• Initiation: chemical carcinogens are converted into chemical adducts
that bind DNA
• Promotion: proliferation of the cell
• Progression: progression of proliferated cell to cancer cell

68. Chemical carcinogenesis of benzopyrene
Tobacco smoking
(Benzopyrene)
Activates p53
Activates cytochrome
p450
Benzopyrene
Vicinal diol epoxide
Carbonium ion
(nucleophilic)
Benzopyrene epoxide
Binds to DNA
DNA damage and
tumorigenesis

69. Microbial carcinogenesis
A. Bacterial
Helicobacter
pylori
Gastric adenocarcinoma, Maltoma
B. Viruses
EBV Nasopharyngeal carcinoma, burkitt lymphoma, post transplant lymphoproliferative disorders, EBV
positive DLBCL NOS, EBV positive smooth muscle tumors, Hodgkin lymphoma (except NLPHL and
NS), gastric ca
HPV Squamous cell carcinoma cervix, penis, vulva and vagina adenocarcinoma cervix, oropharyngeal
carcinoma, HPV associated sinonasal carcinoma
HBV and HCV Hepatocellular carcinoma
HIV Kaposi sarcoma, NHL, Primary effusion lymphoma
HTLV Adult T cell leukaemia/ lymphoma
HHV-8 Kaposi sarcoma, primary effusion lymphoma
C. Parasites
Schistosomia Squamous cell carcinoma bladder
Clonorchis sinensis Cholangiocarcinoma, pancreatic carcinoma, hepatocellular carcinoma
Fasciola hepatica Cholangiocarcinoma

70. Human papilloma virus
• Oncogenic DNA virus
• HPV 16,18,31,33,45- causes cancer
• HPV 6,11- benign lesions (condyloma accuminata)
• Pathogenic proteins responsible for cancer
• HPV E6 protein: binds to p53 and causes ubiquitination and subsequent
degradation in proteasomes
• HPV E7 protein: Binds to RB and releases E2F which is a transcription
activator
• It exist as two forms: episomal form and integrated form
• Integrated form is responsible for cancer

73. EBV virus
• It is herpes virus that infects B cells through CD21 (CR2: complement
receptor 2)

74. • EBNA-1 : binds EBV genome to Host genome ensuring viral genome to be partitioned to
daughter cells of infected parent cells during cell division, maintains viral episome
• EBNA-2 : promotes B cell replication and activation by activating transcription of certain
host proteins like cyclins
• EBV LMP-1 : it is a mimicker of CD40 molecule binding to TNF receptor associated factors
(TRAFs) and adaptor proteins activating NF-kB and JAK-STAT pathway leading to cytokine
production and B cell activation. Also activates antiapoptotic factor bcl-2
• vIL-10: inhibits macrophages and dendritic cells and suppresses antiviral T cell responses

76. Hepatitis B and C virus
• 70-85% oh HCC world wide are due to HBV and HCV
• HBV is most commonly associated with HCC
• HBx is the main protein responsible for carcinogenesis
• HBx inactivates p53 as well as causes transcriptional activation of
several protooncogenes

78. Helicobacter pylori
• Causes gastric carcinoma and Maltoma
• Cag A gene responsible for proliferation of cells and cancer
• Cag A is cytotoxin associated A