Encapsulated tumor with
follicular differentiation
Very low malignant potential
Almost always solitary
Treatment
Partial or complete thyroidectomy
Solitary Nodule
Granular Cell Tumor
Malignant
Types
Papillary Carcinoma
General
Most common thyroid malignancy
F>M, 3:1
a/w childhood radiation exposure
Excellent prognosis
Gross and
Microscopic Findings
Multifocal
Empty appearing nuclei
Orphan Annie eyes
Papillary projections within glandular space
Psamomma bodies
Collection of calcified cancer
cells; stain deep purple
Lymphatic invasion
Mets to cervical LNs and lung
Diagnosis
and
Treatment
Dx: FNA
Partial or complete thyroidectomy
Followed by
radiotherapy with
radioactive Iodine
Suppression
therapy
levothyroxine to increase
negative feedback on TSH
secretion
Shrinks the tumor
Follicular Carcinoma
General
F>M
Good prognosis
a/w radiation exposure (less so than
papillary) and iodine deficiency
Gross and Microscopic Findings
Usually a single cold, encapsulated nodule
Haematogenous spread
Anotações:
Rather than lymphatic spread as seen in papillary carcinoma
Mets to lung and bone first
Well-differentiated, uniform follicles
No psamomma bodies
Widely invasive or minimally
invasive classification
Anotações:
Minimally invasive: capsule invasion only (may have some vascular invasion of a few small vessels)
Widely invasive: extends through capsule and into thyroid parenchyma and vasculature
Hurthle cell carcinoma
often considered a variant
Diagnosis and Treatment
FNA is NOT diagnostic
Microscopically the same as follicular adenoma
Need evidence of invasion
Definitive dx requires lobectomy
Treated similarly to papillary carcinoma
Medullary Carcinoma
Findings
Increased serum calcitonin
Causes diarrhoea
Tumor marker
May have ectopic hormone production,
paraneoplastic syndromes
Ex. ACTH causing Cushing syndrome
Calcitonin amyloid material in stroma
Mets
Early regional LN mets common
Distant mets to liver, lung, bone and brain
Diagnosis and Treatment
Dx: FNA, increased calcitonin
Total thyroidectomy and genetic
screening of RET gene if familial
General
Neuroendocrine tumor of parafollicular C cells
C-cell hyperplasia is a precursor lesion
Causes
Sporadic (80%)
Poorer prognosis than familial type
Unilateral
Familial (20%)
a/w MEN 2A and 2B
Anotações:
Recall:
MEN 2A- medullary carcinoma, hyperparathyroidism, pheochromocytoma
MEN 2B- medullary carcinoma, mucosal neuromas, pheochromocytoma
Younger patients
Bilateral and multicentric
Anaplastic
General
Elderly women
a/w multinodular goiter and positive follicular cancer history
Rapidly aggressive
VERY poor prognosis
Early dissemination
Invasion of local
structures (trachea,
oesophagus) common
50% have lung mets at presentation
Gross and Microscopic
Findings
Regions of spontaneous
haemorrhage and
necrosis
Infiltration of adjacent structures
Diagnosis and Treatment
Dx: FNA or surgery if
inconclusive
Palliative treatment
Partial surgical
resection
Tumor often
compresses the trachea
Extensive resection of tumor
and surrounding structures
generally NOT indicated