advance histopath

Question 1

what is a teratoma

Answer 1

type of germ cell tumour

Question 2

what types of tissue can teratomas contain

Answer 2

ectoderm

mesoderm

endoderm

Question 3

where do teratomas form

Answer 3

Common in ovary and testes but can occur in other places

can occur from germ cells that were left behind during embryonic migration from the posterior dorsal ridge

ie in the middle of the body: pineal, base of the skull, mediastinum, retroperitoneum and sacro-coccygeal area

Question 4

Answer 4

ectoderm teratoma

squamous epithelium

hair follicles

Question 5

Answer 5

mesoderm teratoma

cartilage surrounded by metabolically active spindle cells

Question 6

Answer 6

GI epithelium

endoderm teratoma

Question 7

different types of ovarian tumour

Answer 7

from the surface epithelium ie mesothelial lining

Sex cord/stroma – graffian follicle and supporting cell (not ovum in centre)

Germ cell tumour

• including teratoma
• Yolk sac and chorio are from the trophoblasts

Question 8

testicular germ cell tumours

Answer 8

Question 9

classification of teratomas

Answer 9

• Divided into mature and immature
• Mature – mature tissue
  
  • mature either solid or cystic (ie dermoid cyst)
  • can become malignant – any type of tumour because any type of tissue can be present
• Immature – embryonic or fetal tissue – bad prognosis - because the tissue can proliferate because have the stem cells
• Also contain mixed elements

can be monodermal - ie one layer

Question 10

epidemiology of teratomas

Answer 10

more common in ovary than testes

in ovary - more ‘‘benign’’ ie more mature = act benign

in testes more ‘‘malignant’’ - ie more immature = act malignant

Subtle difference in genetics that make this difference

Incidence is increasing

Question 11

Answer 11

testicular teratoma

Variable looking because have a lot of different tissues

Question 12

Answer 12

mixed germ cell tumour

70% teratoma 30% embryonal ca

Solid

Immature

Question 13

Answer 13

• Teratoma
• Extra-dermal elements – skin, teeth, hair
• Mature cystic
• A lot of ovarian are cystic – more commonly known as dermoid cyst

Question 15

grading of teratomas

Answer 15

look at how much immature neural tissue there is

Question 16

Answer 16

immature nerual tumour

neuroectoderm

primitive – making spinal cord and brain

Question 17

where are neuroendocrine tumours found

Answer 17

every tissue of the body

GIT - very common, SI and rectum most common

• Foregut, mid and hindgut
• foregut - thymus, oesophagus, lung stomach, duodenum, pancreas
• migut - appendix, ileum, cecum, ascending colon
• hindgut - distal bowel, rectum
• Hindgut tumours – low grade
• Mid gut – highgrade

lung and bronchus - common

L is GIT, R is pancreas

red granular cytoplasm cells

Question 18

electron microscopy of normal neuroendocrine cells

Answer 18

See the granules

Question 19

immunohistochemical markers for neuroendocrine tumours

Answer 19

chromogramin – core of the neurosecretory granules – marker for these tumours

synaptophysin - specific marker for neuroendocrine tumours

CD56 also mark NK cells

Also mark tumour for the hormone that it produces ie gastrin, serotonin, insulin

Question 20

Answer 20

neuroendocrine tumour

Question 21

grading of neuroendocrine tumour

Answer 21

Ki-67 is a marker for the cells that are actively proliferating – more = high grade. <3% low grade well differentiated neuroendocrine tumour

Number of mitoses

Question 22

neuroendocrine tumour behaviour

Answer 22

Grade determines behaviour – high = more aggressive – chemo, may have met – need more aggressive therapy

Imaging – low grade – measure uptake of chemical processed by neuroendocrine cell – when v malig – less diff so just use PET

Question 23

staging of neuroendocrine tumour

Answer 23

TNM system – staging system depends on the site of the tumour

Question 24

syndromes associated with hypersecretion

Answer 24

zollinger-ellison = tumour of the pancreas or duodenum – gastrin = gastroin hypersecretion by parietal cell = acid = peptic ulcer of stomach, duodenum, jejunum

carcinoid = serotonin

hypoglycaemia = insulin