Terminology and classification of tumors

Question 1

Clinicopathologic groups:

Answer 1

• preneoplastic/dysplastic lesions
• neoplasias
• tumor-like lesions

Question 2

Types of neoplasias

Answer 2

• benign
• semimalignant (borderline)
• in situ carcinoma
• malignant

Question 3

Nomenclature of tumors

Answer 3

benign neoplasias are usually called by tissue of origin with “-oma” at the end (lypoma)
Can be tricky because malignant tumors also can end eitj -oma (lymphoma) or tumor-like lesions (granuloma, haematoma, actinobacilloma)

Question 4

Epithelial malignant tumors are usually called …

Answer 4

carcinoma

Question 5

Mesenchymal malignant tumors are usually called …

Answer 5

sarcoma

Question 6

What does ending -blastoma mean in case of tumor?

Answer 6

highly undifferentiated tumors (nephroblastoma, retinoblastoa etc)

Question 7

Dysontogenic tumors - ?

Answer 7

individual category somewhere between neoplasias and developmental anomalies

Question 8

2 big groups of dysontogenic tumors

Answer 8

Choristoma and Hamartoma

Question 9

Choristoma

Answer 9

type of heterotopia. Normally differentiated tissue developed at a WRONG LOCATION

Question 10

Hamarthoma

Answer 10

Focal malformation. Abnormally differentiated tissue at anatomically normal location.
Teratomas are kind of hamarthomas

Question 11

Teratoma

Answer 11

…

Question 12

Differentiation of neoplasias?

Answer 12

More differentiated tumor is, more it resembles tissue of origin, more benign characteristics it has

Question 13

Benign vs. Malignant basic characteristics

Answer 13

• localized (capsule), slower growth, well-removable, no recurrence usually <-> faster growth, invasion into surrounding tissues
• no invasion or metastasis <-> metastasis to distant organs
• can cause compression but usually does not harm patient’s life <-> can cause death
• benign tumors are genetically “simple” and stable (less mutation and less variation in genetic structure over time)

Question 14

Can types of tumors overlap?

Answer 14

Yes. Criteria for differentiation are:
- differentiation
- pace of growth
- local invasion
- metastasis

Question 15

Can benign tumors become malignant?

Answer 15

Yes they can. Also there can be functional malignancy

Question 16

Is it always possible to distinguish between malignant and benign tumors?

Answer 16

No. E.g. tumor is growing, invading the tissue but doesn’t give metastasis -> SEMIMALIGNANT TUMORS

Question 17

Semimalignant tumors

Answer 17

Have mostly characteristics of benign tumors BUT they are locally invasive, infiltrating surrounding tissues ! also tend giving recurrence
NO metastasis

Question 18

In situ carcinoma - ?

Answer 18

• Pre-invasive phase of an epithelial malignancy
• localized process
• proliferation will no go through basement membrane !! (won’t affect dermis)
• skin -> Bowen or multicentric in situ carcinoma
• mammary gland -> intraductal and intralobular carcinoma
• in case of mucosas - if it does not go through lamina muscularis mucosae
• important to make several slides !!

Question 19

Neoangiogenesis

Answer 19

• Neoplasm will form new small blood vessels that will be O2 source for tumor.
• if cell proliferation rate > rate of neoangiogenesis -> hypoxia -> necrosis

Question 20

Grade of differentiation

Answer 20

Level of cell differentiation of the tumor’s parenchyma is variable
-G1 well-differentiated
-G2 moderately differentiated
-G3 Poorly differentiated / anaplastic
(growing ability, invasion ability, prognosis of disease, therapy modality)

Question 21

Anaplasia - ?

Answer 21

lack of differentiation. Tissue will lose original functions but can gain new ones.

Question 22

Characteristics of anaplasia:

Answer 22

• anisocytosis, anisokaryosis, kariomegaly, increased nuclear:cytoplasmic ratio, hypo/hyper chromasia,
• prominent NUCLEOLUS,
• increased mitotic activity,
• irregular chromosomes

Question 23

Anisocytosis - ?

Answer 23

Difference in size and shape of cells

Question 24

Anisokaryosis - ?

Answer 24

Variation in nuclear size and shape

Question 25

Karyomegaly - ?

Answer 25

enlargement of the nucleus (2-3x normal size)

Question 26

Nuclear : cytoplasmic ratio

Answer 26

nuclei- cell and nuclear cytoplasm ratio 1:1 instead of 1:4/1:6

Question 27

Hypo- / hyperchromasia

Answer 27

Lack or hyper staining of the nuclei

Question 28

pre-neoplastic lesions

Answer 28

Genetic deformities can be already marked with molecular methods but there are no clinical signs

reversible pre-neoplastic lesions (dysplasia, metaplasia) are frequently precursors to neoplastic progression

Question 29

Acquired pre-neoplasia

Answer 29

some chronic regenerative cell proliferation (e.g. liver cirrgosis)

Question 30

Tumor-like lesions. Examples

Answer 30

• macroscopically look like tumors
• e.g.
• idiopathic nodular hyperplasia (liver, pancreas, spleen, adrenal gland)
• cystic mucinous hyperplasia in gall bladder
• chronic inflammatory tissue proliferation
• hyperregeneration
• follicular cyst in skin