Transcript What work ups are needed, if any?

What work ups are needed,
if any?
MALIGNANT VS. BENIGN
• History taking
• Physical examination
• Fine-needle aspiration
biopsy (FNAB)
• Other imaging and
laboratory evaluation
Evaluation of a Thyroid Nodule
• History
– Risk factors for thyroid cancer
•
•
•
•
•
•
•
•
History of thyroid irradiation, especially in infancy or childhood
Age < 20 yr
Male sex
Family history of thyroid cancer or multiple endocrine neoplasia
A solitary nodule
Dysphagia
Dysphonia
Increasing size (particularly rapid growth or growth while receiving thyroid
suppression treatment)
• Physical Examination
– Signs that suggest thyroid cancer
• stony hard consistency or fixation to surrounding structures
• cervical lymphadenopathy
• hoarseness due to recurrent laryngeal nerve paralysis
Testing
• Fine-Needle Aspiration Biopsy (FNAB)
– Cornerstone in the evaluation of solitary thyroid
nodules and also dominant nodules within
multinodular goiters
– Currently considered to be the best first-line
diagnostic procedure in the evaluation of the
thyroid nodule
Fine-Needle Aspiration Biopsy
• Advantages:
– Safe
– Cost-effective
– Minimally invasive
– Leads to better selection of patients for surgery
than any other test (Rojeski, 1985)
– Halved the number of patients requiring
thyroidectomy (Mazzaferri, 1993)
– Double the yield of cancer in those who do
undergo thyroidectomy (Mazzaferri, 1993)
Fine-Needle Aspiration Biopsy
• Limitations
– Skill of the aspirator
– Expertise of the cytologist
– Difficulty in distinguishing some benign cellular adenomas from
their malignant counterparts (follicular and Hurthle cell)
•
•
•
•
•
Sensitivity: 65 – 98% (avg. 83%)
Specificity: 72 – 100% (avg. 92%)
Positive Predictive Value: 50 – 96% (avg. 75%)
False-negative Rates: 1.5 – 11.5% (avg. < 5%)
False-positive Rates: 0 – 8% (avg. 3%)
Reference: Gharib, H. (2008). Fine-Needle Aspiration Biopsy of the Thyroid Gland. Thyroid Disease Manager.
Fine-Needle Aspiration Biopsy
• Four Categories of Cytologic Diagnosis
– Benign (Negative) – 69%
– Suspicious (Indeterminate) – 10%
– Malignant (Positive) – 4%
– Unsatisfactory (Nondiagnostic) – 17%
Reference: Gharib, H. (2008). Fine-Needle Aspiration Biopsy of the Thyroid Gland. Thyroid Disease Manager.
CT/MRI
THYROID STIMULATING HORMONE (TSH)
• A sensitive TSH assay is
useful in the evaluation
of solitary thyroid
nodules
– Benign = low serum TSH
– Malignant = cannot be
determined
SERUM THYROGLOBULIN
• Not helpful diagnostically
• Elevated in most benign thyroid conditions
• Other thyroid function tests are usually not
necessary in the initial workup
SERUM CALCITONIN
• Elevated levels are highly
suggestive of medullary
thyroid carcinoma (MTC)
• Once the mainstay in the
diagnosis of FMTC
• Replaced by sensitive
polymerase chain reaction
(PCR) assays for germline
mutations in the RET protooncogene
• Currently used as tumor
markers to monitor patients
who have been treated for
MTC
Staging and Prognosis
• AGES and AMES scoring systems
–
–
–
–
–
A
G
M
E
S
Age of patient
Tumour Grade
Distant metastasis
Extent of tumour
Size of tumour
• Both scoring systems have identified 2 distinct subgroups;
– Low-risk group; Men 40years or younger, women 50 or younger, without
distant metastasis (bone & lungs)
– Older patients with intrathyroid follicullar/papillary carcinoma, with
minor capsular involvement with tumours < 5cms in diameter
– High –risk group; All patients with distant metastasis
– All older patients with extrathyroid papillary/follicular carcinoma &
tumours >5 cms regardless of extent of disease
MAICS
AMES
Treatment Options
Surgical Treatment: Papillary CA
High risk or bilateral tumors:
Total or near - total thyroidectomy
Minimal Papillary Thyroid Tumor
Unilateral lobectomy and isthmusectomy
Total Thyroidectomy
Unilateral Lobectomy
•Enables the use of RAI for
•Lower complication rate
detecting and treating residual
•Recurrence is unusual (5%)
thyroid tissue and metastatic
•Excellent prognosis
disease.
•Makes serum Tg level a more
sensitive marker of recurrent or
persistent disease
•Eliminates contralateral occult
cancer as sites of recurrence
•Reduces risk of recurrence
•Increases survival
•Decreases 1% risk of progression
to ATC
•Reduces need for reoperative
surgery
Why Thyroidectomy?
• Recurrence rates are lowered and survival is
improved when a patient underwent
thyroidectomy
• Diminished survival was noted in patients with
low-risk disease
Total Thyroidectomy
• Enables the use of RAI for detecting and treating
residual thyroid tissue and metastatic disease.
• Makes serum Tg level a more sensitive marker of
recurrent or persistent disease
• Eliminates contralateral occult cancer as sites of
recurrence
• Reduces risk of recurrence
• Increases survival
• Decreases 1% risk of progression to ATC
• Reduces need for reoperative surgery
Rationale for total thyroidectomy
1) 30%-87.5% of papillary carcinomas involve
opposite lobe (Hirabayashi, 1961, Russell, 1983)
2) 7%-10% develop recurrence in the contralateral
lobe (Soh, 1996)
3) Lower recurrence rates, some studies show
increased survival (Mazzaferri, 1991)
4) Facilitates earlier detection and tx for recurrent
or metastatic carcinoma with RAI (Soh, 1996)
5) Residual WDTC has the potential to
dedifferentiate to ATC
Indications for total thyroidectomy
1) Patients older than 40 years with papillary or
follicular carcinoma
2) Anyone with a thyroid nodule with a history of
irradiation
3) Patients with bilateral disease
Rationale for subtotal thyroidectomy
1) Lower incidence of complications
 Hypoparathyroidism (1%-29%) (Schroder, 1993)
 Recurrent laryngeal nerve injury (1%-2%) (Schroder,
1993)
 Superior laryngeal nerve injury
2) Long term prognosis is not improved by total
thyroidectomy (Grant, 1988)
Non- Surgical approach
• External Beam Radiotherapy and
Chemotherapy
• Radioiodine Therapy
• TSH Suppresion Therapy