This document provides an overview of neoplasia (new abnormal growths or tumors). It defines neoplasia and discusses the classification of tumors as benign or malignant based on characteristics like differentiation, growth rate, invasion and metastasis potential. It also covers tumor nomenclature, risk factors for cancer like age, environment, heredity and pre-existing conditions. The document summarizes key concepts around epidemiology, molecular basis of cancer development, and laboratory diagnosis of tumors.

1. Neoplasia

2. Neoplasia
• Definitions
• Classification
• Nomenclature
• Characteristics of benign and malignant neoplasms

3. Neoplasia
• Cancer is one of the leading causes of death
worldwide.
• Emotional and physical suffering by the
patient.
• Different mortality rate …..
– Some are curable
– Others are fatal

4. Neoplasia
• Neoplasia = new growth
• Neoplasm = tumor
• Tumor = swelling
• The study of tumors = Oncology
– Oncos = tumor + ology = study of

5. Neoplasia
• Definition:
– is an abnormal mass of tissue,
– the growth of which is uncoordinated with that of normal
tissues,
– and that persists in the same excessive manner after the
cessation of the stimulus which evoked the change
– With the loss of responsiveness to normal growth
controls

6. Non-Neoplastic Proliferation:
*Controlled & Reversible
• Hypertrophy – Size
• Hyperplasia – Number
• Metaplasia – Change
• Dysplasia – Disordered

7. Neoplasia
• Classification
– Benign
– malignant

8. Neoplasia
• Benign tumors :
– Will remain localized
– Cannot spread to distant sites
– Generally can be locally excised
– Patient generally survives

9. Neoplasia
• Malignant neoplasms:
– Can invade and destroy adjacent structure
– Can spread to distant sites
– Cause death (if not treated )

10. Neoplasia
• All tumors benign and malignant have two
basic components:
–Parechyma: made up of neoplastic cells
–Stroma: made up of non-neoplastic, host-
derived connective tissue and blood vessels

11. Neoplasia
• The parenchyma:
– Determines the biological behavior of the tumor
– From which the tumor derives its name

12. Neoplasia
• The stroma:
– Carries the blood supply
– Provides support for the growth of the
parenchyma

13. • In some tumors, the stromal support is scant
and so the neoplasm is soft and fleshy.
• In other cases the parenchymal cells
stimulate the formation of an abundant
collagenous stroma, referred to as
desmoplasia.

16. Nomenclature
Benign tumors:
• prefix + suffix
• Type of cell + (-oma)

17. • Benign tumors arising from mesenchymal
tissue,
• cell of origin + oma
– Benign tumor arising in fibrous tissue:
Fibro + oma = Fibroma
- Benign tumor arising in fatty tissue:
Lipo + oma = lipoma

18. • Benign tumor arising in cartilage
chondro + oma = chondroma
• Benign tumor arising in smooth muscle
Leiomyo + oma = leiomyoma
• Benign tumor arising in skeletal muscle
Rhabdomyo + oma = rhabdomyoma

19. • epithelial benign tumors are classified on the
basis of :
– The cell of origin
– Microscopic pattern
– Macroscopic pattern

20. – Adenoma : benign epithelial neoplasms producing
gland pattern….OR … derived from glands but not
necessarily exhibiting gland pattern
– Papilloma : benign epithelial neoplasms growing
on any surface that produce microscopic or
macroscopic finger-like pattern

23. • Polyp : a mass that projects above a mucosal
surface to form a macroscopically visible
structure.
e.g. - colonic polyp
- nasal polyp

26. • Examples :
– Respiratory airways: Bronchial adenoma
– Renal epithelium: Renal tubular adenoma
– Liver cell : Liver cell adenoma
– Squamous epithelium: squamous papilloma

27. Malignant tumors:
– Malignant tumor arising in mesenchymal tissue :
SARCOMA
– Cell of origin + sarcoma
• From fibrous tissue: Fibrosarcoma
• From bone : Osteosarcoma
• From cartilage : chondrosarcoma

28. Malignant neoplasm of epithelial cells origin derived
from any of the three germ layer , are called
Carcinomas.
Cell of origin + Carcinoma
Squamous cells + carcinoma = squamous cell
carcinoma
Adenocarcinoma: One with a glandular growth
pattern microscopically.

29. Adenocarcinoma

30. Carcinoma

31. Adenocarcinoma: One with a glandular
growth pattern microscopically.

32. Squamous cell carcinoma

33. Clear Cells Renal Carcinoma

34. (3) Special nomenclature
① Blastoma: tumors rigging in immature tissue
or nervous tissue, most of them are malignant
e.g.medulloblastoma,retinoblastoma,
nephroblastoma,Neuroblastoma
② Some tumors attaching the suffix-oma.
But malignant
e. g. seminoma, lymphoma, melanoma,
dysgerminoma, glioma, hepatoma

35. ③ Some malignant tumors, but called disease.
e. g. leukemias, paget’s disease
④ Some malignant tumors nominated by
scientists’ name
e. g. Hodgkin’s disease, Ewing’s tumor
⑤ Mixed tumors: tumors which derived from one
germ layer may undergo divergent
differentiation creating mixed tumors
e. g. mixed tumor of salivary gland

36. Neoplasia
Characteristics of benign and malignant
neoplasms
• Differentiation and anaplasia
• Rate of growth
• Local invasion
• metastasis

37. Neoplasia
1. Differentiation and anaplasia:
• Differentiation means : the extent to which
the parenchymal cells of the tumor resemble
their normal counterparts morphologically
and functionally

38. Neoplasia
• well differentiated = closely resemble their
normal counterparts
• Moderately differentiated
• Poorly differentiated
• Undifferentiated ( Anaplasia )

39. Neoplasia
• Benign tumors = well differentiated
• Malignant tumors =
well differentiated -----> anaplastic

43. Neoplasia
Characteristics of benign and malignant
neoplasms
• Differentiation and anaplasia
• Rate of growth
• Local invasion
• metastasis

44. Neoplasia
• Rate of growth:
– Benign tumors:
• grows slowly
• are affected by blood supply, hormonal effects ,
location
– Malignant tumors :
• grows faster
• Correlate with the level of differentiation

45. Neoplasia
Characteristics of benign and malignant
neoplasms
• Differentiation and anaplasia
• Rate of growth
• Local invasion
• metastasis

46. Neoplasia
• Local invasion :
– Benign tumors :
• Remain localized
• Cannot invade
• Usually capsulated
– Malignant tumors :
• Progressive invasion
• Destruction
• Usually not capsulated

51. Neoplasia
Characteristics of benign and malignant
neoplasms
• Differentiation and anaplasia
• Rate of growth
• Local invasion
• metastasis

52. Neoplasia
• Metastasis :
– Definition : the development of secondary
implants discontinuous with the primary tumor,
possibly in remote tissues.

54. Neoplasia
• Metastasis :
– Cancers have different ability to metastasize
– Approximately 30% patients present with clinically
evident metastases.
– Generally, the more anaplastic and the larger the
primary tumor, the more likely is metastasis

55. Benign Malignant:
• Slow growing,
• capsulated,
• Non-invasive
• do not metastasize,
• well differentiated,
• suffix “oma” eg.
Fibroma.
• Fast growing,
• non capsulated,
• Invasive & Infiltrate
• Metastasize.
• poorly differentiated,
• Suffix “Carcinoma” or
“Sarcoma”

56. Modes of spread
• Metastasis : three pathways
– Lymphatic spread :
– Hematogenous spread :
– Seeding of the body cavities: pleural, peritoneal
cavities and cerebral ventricles

57. Neoplasia
• Lymphatic spread :
– favored by carcinomas
– Breast carcinoma  axillary lymph nodes
– Lung carcinomas  bronchial lymph nodes

58. • Hematogenous spread :
• favored by sarcomas
• Also used by carcinomas
• Veins are more commonly invaded
• The liver and lungs are the most frequently
involved secondary sites.

59. Dysplasia :
– Definiton: a loss in the uniformity of the individual
cells and a loss in their architectural orientation.
– Occurs mainly in the epithelia
– Dysplastic cells shows a degree of : pleomorphism,
hyperchromasia,increased mitosis and loss of
polarity.

60. • Dysplasia does not mean cancer
• Dyplasia does not necessarily progress to
cancer
• Dysplasia may be reversible
• If dysplastic changes involve the entire
thickness of the epithelium it is called :
CARCINOMA IN-SITU

62. • Carcinoma in-situ
– Definition: an intraepithelial malignancy in which
malignant cells involve the entire thickness of the
epithelium without penetration of the basement
membrane.
– Applicable only to epithelial neoplasms.

65. Teratoma:
– Teratoma contains recognizable mature or
immature cells or tissues representative of more
than one germ-cell layer and some times all
three.
– Teratomas originate from totipotential cells such
as those normally present in the ovary and testis.

66. • Such cells have the capacity to differentiate into any
of the cell types found in the adult body.
• So they may give rise to neoplasms that mimic
bone, epithelium, muscle, fat, nerve and other
tissues.
• Most common sites are: ovary, testis

67. Epidemiology
– Will help to discover aetiology
– Planning of preventive measures
– To know what is common and what is rare.
– Development of screening methods for early
diagnosis

69. Neoplasia
• Factors affecting incidence of cancer
– Geographic and Environmental
– Age
– Heredity
– Acquired preneoplastic disorders

70. Neoplasia
• Geographic and Environmental factors:
– Asbestos : mesothelioma
– Smoking : lung cancer
– Multiple sexual partners: cervical cancer
– Fatty diets : colonic cancer

71. Neoplasia
• Age:
– Generally, the frequency of cancer increases with
age.
– Most cancer mortality occurs between 55 and 75.
– Cancer mortality is also increased during
childhood
– Most common tumors of children: Leukemia,
tumors of CNS, Lymphomas, soft tissue and bone
sarcomas.

72. Neoplasia
• Heredity---BRCA 1 &2 mutation
– Inherited Cancer Syndromes
– Familial Cancers
– Autosomal Recessive Syndromes of Defective DNA
repair

73. Heredity
• Inherited Cancer Syndromes:
– Inheritance of a single mutant gene greatly
increases the risk of developing neoplasm
– E.g. Retinoblastoma in children :
• 40% of Retinoblastomas are familial
• carriers of the gene have 10000 fold increase in the risk
of developing Retinoblastoma
– E.g. multiple endocrine neoplasia

74. Heredity
• Familial Cancers:
– All common types of cancers occur in familial form
– E.g. breast, colon, ovary,brain
– Familial cancers usually have unique features:
• Start at early age
• Multiple or bilateral
• Two or more relatives

75. Heredity
– Autosomal Recessive Syndromes of Defective DNA
repair :
• Small group of autosomal recessive disorders
• Characterized by DNA instability

76. Neoplasia
–Acquired preneoplastic disorders: Some
Clinical conditions that predispose to cancer
• Dysplastic bronchial mucosa in smokers lung
carcinoma
• Atypical endometrial hypeplasia endometrial
carcinoma
• Liver cirrhosis  liver cell carcinoma
• Margins of chronic skin fistula  squamous cell
carcinoma

77. • Molecular basis of cancer(carcinogenesis)
• Clinical manifestation of neoplasms
• Laboratory diagnosis of tumors