This document summarizes different types of solitary thyroid nodules (STNs), including their clinical presentations, pathological findings, investigations, and treatment approaches. It discusses STNs that may be caused by multinodular goiter, colloid nodules, cysts, autonomous toxic nodules, various forms of thyroiditis, follicular adenomas, and malignant lesions such as papillary carcinoma, follicular carcinoma, and medullary carcinoma. For each condition, it provides details on symptoms, microscopic pathology, diagnostic testing, and surgical or medical management strategies.

1. Solitary thyroid nodule
By: Yehia Matter EL-ashcker

2. any thyroid disese may present itself
as STN:
1.Clinically apparent solitary nodule on top of MNG
2.Simple nodule eg colloid nodule
3. Autonomous toxic nodule
4. Focal thyroiditis( Hashimoto_De Quervain_Riedel)
5.Cyst eg haemorrghic
6.adenomas eg follicular
7.carcinoma (papillary-follicular-anaplastic-lymphoma)

3. Clinical picture:
• symptom:
1.Neck swelling
2. Painful swelling: in case of
*hae *thyroiditis *malignancy
3. Toxic manifestation :in toxic nodules
4.Criteria of malignany:in malignant nodules
• signs:
1. Usually in lower pole.
2. Firm ,hard or cystic.
3.moves up and down with deglutition

4. investigation:
1.Thyroid scan.
2.US.
3. Thyroid function test.
4.Biopsy:FNAC-true cut needle- excision.

5. treatment scheme
a.Multiple :subtotal thyroiddectomy
b.Solitary :
*cystic ->Aspiration :simple cyst " no further ttt"
->suspicious of malignancy if :
Haemorrhagic aspirate
Incomplete disapperance "i.e
residual mass"
+ve cytological exam
Rapidly reaccumulating:
Managed according to type and operability
*Solid: I123 scan
a.Warm nodules : hemi-
thyroidectomy & biopsy
b.Hot nodules :toxic nodules :
before 45 =hemi-thyroidectomy &
after 45 =1st therapy
c.Cold nodules : biopsy : benign
= hemi-thyroidectomy
& malignant = according to type
an operability

6. 1.clinically apparent solitary nodule on
top of MNG:
Clinically: STN
US: MNG
pathology :NE :STN
MP : dormant nodule (fibrous tissue capsule with
necrotic tissue, area of Haemorrhage & destroyed thyroid follicles)
complications & ttt :as MNG

7. 2-colloid nodule
• female 20-30 years complaining of STN
• MP: fibrous tissue with capsule surrounding inactive thyroid
follicles filled with colloid
• ttt: with compression manifestations, retrosternal extension, bad
cosmosis -> hemithyroidectomy

8. 3- thyroid cyst
• NE :STN with +ve pajet test
• MP : Fibrous tissue capsule containing serous fluid, colloid
material or blood
• US :cyst
• ttt: Aspiration up to 3 times if simple cyst
• suspicious of malignancy (Haemorrhagic aspirate, residual tissue
mass, rapidly reaccumulating, +ve cytology) ->
hemithyroidectomy or total thyroidectomy according to
pathology

9. 4-autonomous toxic nodule "ATN"
• Etiology: autonomous activity of solitary nodule "with no thyroid Ab.)
• pathology :
• NE : STN + toxic manifestations
• ME : over activity nodule surrounded by suppressed thyroid tissue
• this over active nodule consists of autonomously active thyroid follicles
surrounded by fibrous tissue
• Investigation :increase in T3,T4 & decrease in TSH,
• U. S :Solitary solid nodule
• thyroid scan -> hot nodule
• ttt : <45yrs - >hemi-thyroidectomy, >45yrs - >radioactive I131

10. 5.Thyroiditis
A- autoimmune (Hashimoto) thyroiditis :
• 30 - 50 yrs, may give a family history of thyroiditis
• NE :STN +/- Pain & tenderness , rubbery or firm in consistency. Initially - > toxic manifestations, later
on - > manifestations if hypothyroidism
• MP : infiltration of the thyroid gland in the affected area by lymphocytes & plasma cells.
• Complications : Hypothyroidism , Malignant change (malignant lymphoma) - > 70 fold increase in
the risk O (papillary carcinoma)
• Investigation :
• Thytoid function tests : initial hyperthyroidism then hypothyroidism ( increas in TSH & decrease in T3
& T4)
• Thyroid Antibodies : anti microsomal Ab. , anti thyroglobulin Ab.
• Thyroid biopsy
• TTT : hemi-thyroidectomy with retrosternal extension, compression manifestations or suspicious of
malignancy

12. B-subacute thyroiditis (Granulomatous - de Quervain's thyroiditis) :
• Female 30-40 years, history of URTI 2 weeks ago, followed by neck pain
& toxic manifestations
• NE:tender STN
• MP : degeneration of thyroid follicles that become surrounded by
giant cs forming granuloma
• Investigation : increase in Esr, T3,T4 & decrease in TSH, radio active
iodine uptake
• TTT: the disease is self-limited so ttt is primarily symptomatic
(Prednisolone & NSAID)

13. C- Riedel's thyroiditis ( fibrosing or woody) :
• Female with history of collagen disease complaining STN - >
hard, fixed with compression manifestations
• MP :replacement of thyroid tissue by fibrous tissue, which also
invades the adjacent tissue
• Investigation : tissue biopsy, normal thyroid functions, thyroid
scan - > normal uptake but not appear on the scan
• TTT : with sever compression manifestations - > isthmectomy to
decompress the trachea

14. 6- follicular adenoma
• NE :Solitary thyroid nodule which is firm & well encapsulated
• ME :several histological variants (embryonal, fetal, follicular &
microfollicular)
• C/P: STN ( may be functioning)
• Investigations : tisse biopsy - >no anglo capsular invasion
• Thyroid scan - > warm nodules (if functioning)
• TTT :hemi-thyroidectomy

16. 7-Malignant STN
• usually - > papillary, follicular or medullary thyroid carcinoma
• Rarely - > lymphoma or anaplaatic carcinoma
A -Papillary thyroid carcinoma
• 15-40yrs complaining of STN with malignant criteria :
• Rapidly growing & associated with dysphagia & hoarseness of voice
• Hard, >1cm, fixed to the skin or sternomastoid wit enlarged Cx. LNs & +ve berr's
sign
• MP : papillary projections formed of C. T core covered by a malignant cuboidal
epithelium with a characteristic pale empty nuclei - > orphan Annie nuclei +
nuclear drooves & pseudo-inclusion + psammoma bodies.
• Investigations :increasw in S.thyroglobulin thyroid scan - > cold nodule, neck U/S,
CT&MRI, indirect larygoscope & FNAC + metastatic work up

18. B. follicular carcinoma
• female 40-60yrs complaining of STN with malignant criteria
• MP : thyroid follicles with variable degree of differentiation (solid sheets of malignant
cells may be present).
• angiocapsular invasion is a characteristic feature & according to its degree, follicular
carcinoma may be :
• non-invasive : if angiocapsular invasion is minimal
• invasive :if angio capsular is moderate or marked
• spread mainly by blood, differentiated tumour & may be functioning
• investigations :
• increase in S.thyroglobulin , Thyroid scan - >cold nodule , Neck U/S, CT&MRI
• Indirect larygoscope & trucut or open surgical biopsy + metastatic work up
•

20. ttt of differentiated thyroid carcinoma (papillary & follicular)
• 1- total (in high risk group) or near total thyroidectomy (in low risk
group) to avoid injury of parathyroids & RLN at least on one side
• 2- Lymphadectomy : for involved Cx. LNs -> cherry 🍒 picking or
modified block dissection "spare sternomastoid, accessory nerve &
Internal jugular vein"
• 3-thyroid tissue suppression :post operative thyroxin in a full suppressive
dose (making TSH < 1 micro micro /L) as tge tumour is TSH dependant
• 4-radiactive iodin scanning and ablation : post operative whole body
scan using radioactive I131 to detect metastasis (done after stoppage
of T4 for 6 weeks in order to permit a high stimulating level of TSH on
the metastasis) - > if metastasis is found - >theraputic dosses of radio
active iodine (I131)

21. c. Medullary thyroid carcinoma
• ♀ 40-60yrs complaining of STN with malignant criteria
• MP : aheets of malignant cs " spindlr shaped or polygonal)
separated by collagen & amyloid (amyloid is a diagnostic
finding)
• +ve immunohistocemistry for calcitonin
• metastasize early - > 50% of patients have neck LNs at time of
diagnosis
• , functioning tumour - >secretes calcitonin, CEA, PGs& serotonin
& doses not taje up radioactive I

23. TTT :
• 1-ttt pheochromocytoma 1st if present
• 2- MTC is ttt by :
• Total thyroidectomy
• lymphadenectomy ( routine central neck clearance + ipsilateral
modified radical block dissection if tumor > 1.5 cm)
• adjuvent radio & chemotherapy
• 3- prophylactic total thyroidectomy for family member proved
to have RET gene mutation

24. Thank you