Management Of Solitary Thyroid NodulePresentation Transcript
“ MANAGEMENT OF SOLITARY THYROID NODULE ”
NHDC & RI
Anxiety induced by the fear of malignancy in Solitary Thyroid Nodule (STN) against a background of common benign nodular disease generates the diagnostic dilemma for the clinicians and make its management controversial.
With the availability of current diagnostic techniques it is now possible to have a selective approach to management of STN by identifying those patients likely to have malignancy and avoiding thyroidectomy in majority of patient with being benign disease.
A thyroid nodule is a palpable swelling in a thyroid gland with an otherwise normal appearance.
Most are benign
12-28% are malignant STN
Four times more common in women
D/D of STN:
Carcinoma : Papillary (75%)
Thyroid lymphoma (5%)
Others : Inflammatory thyroid disoders
Chronic lymphocytic thyroiditis
PATIENT PRESENTATION AND DIAGNOSIS :
- Majority are asymptomatic
Most are euthyroid, with only
1% of nodules carry hyperthyroid or thyrotoxicosis.
- Palpable lump
- Neck pressure (spontaneous haemorrhage into nodule)
- Symptoms of hypothyroidism
- Symptoms of hyper thyroidism
OBJECTIVES AND EVALUATION OF THYROID NODULES To exclude malignancy Regarding adequate and ideal treatment of STN METHODS TO ACHIEVE THE OBJECTIVES Clinical evaluation Investigations : FNAC Test of thyroid function Thyroid scintiscan Thyroid USG Fluorescant scanning MRI/CT – very rarely
- Multiple nodules and diffuse nodularity => more benign diseases
- Firm solitary nodule - malignancy
- About one half of all nodules detected by USG escape detection on clinical examination.
"RED FLAGS" FOR THYROID CARCINOMA
Male – gender (16% male, 10% female)
Extremes in age (< 20 - > 65 yrs)
Rapid growth of nodule
Symptoms of local invasion (dysphagia, hoarseness)
Hard, fixed lesions, nodules > 4 cm
History of radiates to head or neck
Family history of thyroid carcinoma or polyps
: It is i nvestigation of choice
Accuracy – 95%
False negative – 1-11%
False positive – 1-8%
Benign Malignant Suspicious Indeterminate
70% 5-10% Surgery
Follow up Surgery Repeat FNAC
Pit fall : Can not differentiate between follicular adeoma and f. carcinoma
Proton magnetic resonance
TESTS OF THYROID FUNCTION
TSH with or without low T3 and T4 – suggests nodular form of hashimoto's thyroiditis.
TSH with or without elevated T3 and T4 suggests => autonomously hyper functioning nodule
Serum cacitonin measured => any patient with family history of thyroid carcinoma.
Can not distinguish whether nodule is benign or malignant.
Nuclear imaging cannot reliably distinguish between benign and malignant nodule
Differentiate STN with multinodular goitre
Function status of nodule
Whether metastasis of thyroid carcinoma concentrate iodine and could be immenable to treatment with radioiodine
FNAC is inconclusive and scan shows warm or hot nodules Warm nodules – A trial of TSH suppression using thyroxin may cause regression of nodule Autonomously functioning hot nodule – I131 ablation therapy may serve as a useful alternative to surgery.
USG cannot distinguish benign from malignant nodules
change in size of nodules over time, either in follow up of a lesion thought to be benign:
detecting recurrence in patient with thyroid carcinoma
incidence of indeterminate specimen from FNA decreases from 15% - < 4% (when FNA used with USG)
thyroid nodules found incidently during USG of neck for reason not relating to thyroid gland
monitoring size of nudule during thyroxin suppression therapy
CXR : In presence of obstructive symptoms tracheal deviation or suspected retrosternal extension. Cacification within papillary carcinoma of thyroid as psammona bodies. MRI/CT : STN are being found incidently during MRI/CT for reason not relating to thyroid gland. Fluorescent scanning: Determines intra – thyroid iodine content is an unproven technique for defferentiating bening from malignant thyroid nodule currently remains a research tool.
Principles of deciding modalities of treatment : If FNAC – malignant – total thyroidectomy
If Cyst (benign) - completely aspirated.
- if recurrences occurs :
residual nodule is
palpable after aspiration :
If benign and lesion is solid : thyroid scintiscan Low Risk Warm: TSH suppression trial by thyroixin, if response positive ; continue for 6 months or till nodules disappeared Cold : hemithyroidectomy Hot nodules : I131 ablation or hemithyroidectomy High risk – even if FNAC is negative for malignancy hemithyroidectomy is advocated Hemithyrodectomy is useful if FNAC is inconclusive or reported as follicular neoplasm.
At time of hemithyroidectomy – frozen section should be taken if confirm malignancy – total thyroidectomy
If inconclusive : Paraffin section should be taken – if positive – completion thyroidectomy
FOR MALIGNANT NODULE:
partial / total thyroidectomy - remains controversial and debate continues for type of thyroidectomy
Radioiodine therapy should be used as adjunctive therapy
Post operative thyroid replacement is a common practice
Benefits of administration remains controversial specially in low risk patients
Complication of surgery :
Recurrent laryngeal nerve damage
CONCLUSION: With the advent of current diagnostic technique and with their appropriate use in diagnosis of STN, it is now possible to have a selective approach to management of STN by identifying the patient likely to have malignancy and avoiding thyroidectomy in majority of patient with benign diseases who can be given conservative medical treatment.