thyroid nodules Flashcards
thyroid masses
> 4cm
thyroid nodules
1 - 4 cm
small thyroid lesions
( < 1cm)
radiologically detected as they are clinically undetectable
if cancerous, are termed “microcarcinomas” when <= 10mm
what do follicular cells “thyrocytes” produce
thyroglobulin
what do para-follicular cells “c-cells” produce
calcitonin
what do colloid / thyroglobulin store
iodination in colloid
thyroxine
are lymphocytes infiltrative ?
true (any lymphocytes are infiltrative)
how common are thyroid nodules amongst adult UK population ?
5% females
1% males
what are the presentation of thyroid nodules ?
symptomatic
incidental finding (on a scan)
what percentage of thyroid nodules are benign / malignant ?
95% benign
5% malignant
(90% are differentiated thyroid cancers)
what percentage of cancers do thyroid cancers account for ?
1% of cancers (20th most common)
are thyroid cancers most common form of endocrine neoplasm ?
true
examination for thyroid nodules
inspection
feel neck triangles / lymph nodes
feel thyroid
tongue protuberance
drinking water
what inspection during thyroid nodule examination ?
eyes, neck
what areas of neck triangle / lymph nodes to feel
anterior vs posterior
levels: 2,3,4,5,6
thyroid function blood tests
TSH
calcitonin
thyroglobulin
thyroglobulin antibody
PTH (parathyroid hormone)
is TSH always done for thyroid function blood tests ?
yes
calcitonin always done for thyroid function ?
not routinely (only in history or cytology suggestive of MTC)
is thyroglobulin always done for thyroid function ?
no - only for thyroid cancer surveillance
is thyroglobulin antibody always done ?
no - only for thyroid cancer surveillance
is PTH (parathyroid hormone) always done ?
no - only if suspecting parathyroid mass
what is used for thyroid imaging
ultrasound
radioisotope scan
CT
what is U1 grading in thyroid imaging ?
normal
U2 grading
benign
U3 grading
indeterminate / equivocal
U4 grading
suspicious
U5 grading
malignant
when do you go for a radioisotope scan (if TSH supressed - <0.4mlU/L)
to detect cold nodule
hot nodule is toxic adenoma
when do you use CT for thyroid imaging
reserved for local cancer invasion or advanced cases
thyroid cyctology
ultrasound assisted (historically free-hand if >4cm)
when do you proceed to FNAC
any U4 / U5
U3/4
U3 > 1.5
**thyroid cytology
do I need to know about the scoring system in UK (RCP)
non-neoplastic thyroid nodules
multi-nodular goitre MNG (common)
hyperplastic nodule
colloid
non-cancerous thyroid neoplasms
toxic adenoma
non-invasive follicular thyroid neoplasm papillary-like nuclear features (NIFTP) pre-cancer
differentiated thyroid cancers (90% of thyroid cancer)
papillary thyroid cancers 80% - various types
follicular 15% - various types
hurthle cell cancer 5%
primary thyroid lymphoma
need core biopsy
anaplastic thyroid cancer
<1% (very aggressive, 2 tayside cases a year)
medullary thyroid cancer
1%
metastasis to thyroid
(e.g. renal cancer)
how to manage benign symptomatic nodules
may warrant surgery (e.g. compressive or toxic)
how to manage high risk cancer - Thy4/Thy5 discussed at MDT to decide
hemithyroidectomy or total thyroidectomy + radioactive-iodine
how to manage low risk cancer - Thy3a or Thy3f
diagnostic hemi-thyroidectomy
or repeat FNA
how to manage surgical pathology
benign pathology with description or…
cancer type w/ TNM staging
if diagnostic hemi-thyroidectomy showed cancer:
surveillance
completion thyroidectomy + radioactive iodine
(complications of thyroidectomy) seroma
common & settles (<5%)
(complications of thyroidectomy) superficial haematoma
common & settles. consider evacuation if large
(complications of thyroidectomy) hypocalcaemia
only after total thyroidectomy (parathyroid function)
(complications of thyroidectomy) wound infection
uncommon (<5%) if in doubt give antibiotics
(complications of thyroidectomy) scar
abnormal scarring uncommon (<5%) . body image/psychology affecrs QOL
(complications of thyroidectomy) stridor
deep haematoma causing laryngeal oedema. rare (<1%)
(complications of thyroidectomy) RLN injury
voice change & swallow problems. a spectrum
(complications of thyroidectomy) chyle leak
possible with left level vi lymph node dissection
(complications of thyroidectomy) other nerve injuries
