Neoplasms Flashcards
1
Q
Thyroid neoplasms
A
Benign
- Adenoma
- follicular
- Hurthle cell
Malignant
- Carcinoma
- follicular
- papillary
- Hurthle cell
- poorly differentiated (insular)
- anaplastic (undifferentiated)
- medullary - Lymphoma
2
Q
Clinical features of thyroid adenomas
A
- solitary painless nodules
- usually cold nodules
- rarely hyperfunctioning
3
Q
Morphology of thyroid adenomas
A
G:
- rounded, encapsulated (fibrous capsule), well demarcated
- bulging from cut surface
- HCA: orange-brown
M:
- completely surrounded by an intact capsule
- follicles - uniformed, distinct from surrounding parenchyma
- macrofollicular, microfollicular and mixed cells
- monotonous cells
- cystic change & hemorrhage
- HCA: cells show oncotic change, plump, abundant pink cytoplasm
4
Q
Differential diagnoses of thyroid adenomas
A
- Follicular carcinoma
- capsular/vascular invasion - Dominant nodule in MNG
- no complete capsule, less distinct from surrounding parenchyma, multiple nodules in background - Follicular variant of papillary thyroid carcinoma
- nuclear features
5
Q
Pathogenesis of thyroid carcinomas
A
- Genetic aberrations
- follicular - RAS mutations, specific translocations
- papillary - RET gene, BRAF mutations
- medullary: MEN2 syndrome (RET)
- anaplastic: p53 mutations - Environmental
- ionising radiation
- longstanding multinodular goitre
6
Q
Features of thyroid follicular carcinoma
A
- capsular/vascular invasion
- more common in women
- slow growing painless cold nodule, typically solitary
- prognosis depends on degree of invasion
- mets through bloodstream - lungs, bone, liver etc
7
Q
Morphology of thyroid follicular carcinoma
A
G:
- minimally invasive: well defined, hard to find capsular invasion
- widely invasive: obvious, extensive capsular/extrathyroidal invasion
M:
- same as follicular adenoma + invasion
- surrounded by intact capsule
- follicles - uniformed, distinct from surrounding parenchyma
- macrofollicular, microfollicular & mixed cells, montonous cells
- cystic change & hemorrhage
8
Q
Features of thyroid papillary carcinoma
A
- 20-40y, can occur in children
- associated with ionising radiation
- painless cold nodule, can be multifocal
- enlarged cervical lymph nodes
- if severe - hoarseness, cough, dysphagia
- good prognosis
- lymphatic not vascular spread
9
Q
Morphology of thyroid papillary carcinoma
A
G:
- solitary/multifocail
- encapsulated to infiltrative
- whitish nodules, cystic change, calcifications & fibrosis
M:
- nuclear features!!
- finely dispersed chromatin - ground glass/Orphan Annie eye nuclei)
- nuclear grooves
- pseudoinclusions (cyoplasmic invaginations)
10
Q
Types of thyroid papillary carcinomas
A
- Classical PC
- branching well formed papillae w fibrovascular cores
- uniform, cuboidal cells
- Psammoma bodies - concentrically calcified bodies w papillae cores
- fibrosis, calcifications
- lymphatic invasion - Follicular variant
- Encapsulated variant
11
Q
Features of thyroid anaplastic carcinoma
A
- mean 65y, associated with underlying MNG (50%) or well differentiated thyroid carcinoma (20-30%)
- rapidly enlarging bulky mass
- compressive symptoms - dyspnea, dysphagia, hoarseness
- often spreads beyond thyroid - mets to lung
- dismal prognosis
12
Q
Morphology of thyroid anaplastic carcinoma
A
- cells - highly pleomorphic
- giant tumour cells
- spindle cells - sarcomatous features
- small anaplastic cells
13
Q
Features of thyroid medullary carcinoma
A
- neuroendocrine tumour, derived from parafollicular C cells
- 80% sporadic (50-60y), 20% MEN/familial (20y)
- mass effects
- paraneoplastic syndromes
- raised serum calcitonin - good for screening
- sporadic prognosis is worse than familial
14
Q
Morphology of thyroid medullary carcinoma
A
G:
- localized, large, solitary (sporadic)
- multinodular, small, bilateral (MEN, familial)
- necrosis & hemorrhage
- invasion beyond thyroid
M:
- cells: epithelioid or spindled, salt & pepper chromatin
- architecture: nests, trabeculae, follicles
- background: amyloid (Congo Red), C cell hyperplasia - MEN, familial
