Pathology very important issue one should study

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