Download subtotal thyroidectomy

Malignant Thyroid Disease
HISTORY OF PRESENT
ILLNESS
10 years PTC
slowly growing
nodular ant. neck mass
2 years PTC
rapid increase in the
size of mass
6 months PTC
hoarseness & difficulty
of swallowing
Admission
Review of Systems
• No fever, no weight loss, no tremors
• No chest pain, no easy fatigability
• No abdominal pain
• Past Medical History: unremarkable
• Family History: unremarkable
Physical Exam
• PR = 100/min
• RR = 20/min
• T = 37oC
• No exopthalmos
• 25x20cm multinodular, firm right
anterolateral neck mass
• Palpable cervical adenopathies post.
to the sternocleidomastoid
SALIENT FEATURES
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39 y/o, female
Anterior neck mass
Hoarseness
Difficulty of swallowing
Malignant Thyroid Disease
1. What is your clinical impression?
What are the differential diagnosis?
• Thyroid Cancer
Thyroid nodules
• Hx: time of onset, change in size, and
associated symptoms such as pain,
dysphagia, dyspnea, or choking
• Pain-raise suspicion of intrathyroidal
hemorrhage in a benign nodule, thyroiditis,
or malignancy
• Hoarseness- secondary to malignant
involvement of the recurrent laryngeal nerve
• Increase risk of malignancy: Hx of ionizing
radiation and family hx of thyroid cancer
PE:
• Thyroid masses- move with
swallowing
• Hard, gritty, fixed nodules- more likely
to be malignant
• Lymph node involvement- increases
the risk of malignancy
39 y/0, female from Bicol
PR=100/min RR=20/min T=37C
Growing nodular anterior neck mass
(-) exophthalmos
Hoarseness and difficulty in
swallowing
25x20 multinodular, frim, right
anterolat neck mass which moves with
deglutition, with a hard nodule (5x3)
within the big mass
(-) Fever, weight loss, tremors
Palpable cervical adenopathies
(-) chest pain, easy fatigability
(-)abdominal pain
Unremarkable PMH, FH
Specific Tumor Types:
Papillary Carcinoma
• 80 % of all thyroid malignancies in iodine
deficient areas and in individuals exposed to
external radiation.
• 2:1 female to male ratio
• Mean age: 30-40
• Euthyroid
• Slow growing mass with calcification,
necrosis, or cystic change apparent grossly
• Dysphagia, dyspnea, and dysphonia
• Lymph node metastases
Specific Tumor Types:
Follicular Carcinoma
• More common in iodine deficient
areas
• 3:1 female to male ratio
• Mean age: 50 years
• Solitary thyroid nodule
• Cervical lymphadenopathy is
uncommon
• Distant metastasis may be present
Hurthle Cell Carcinoma
• Similar to follicular carcinoma
• Multifocal
• Bilateral
• More likely to metastasize to local
nodes and distant sites
Medullary Carcinoma
• Neck mass with palpable cervical
lymphadenopathy
• Dysphagia, dyspnea, dysphonia
• 1.5:1 female to male ratio
• Mean age: 50-60, patients with
familial disease present at a younger
age
• Unilateral, multicentric
Anaplastic Carcinoma
• Most aggressive
• Presents in the 7th or 8th decade of life
• Long standing neck mass which
rapidly enlarges, may be painful
• Associated with dysphonia,
dysphagia, and dyspnea
• Palpable lymphnodes
1. What is your clinical impression? What are
the differential diagnosis?
Goiter-may result from iodine
deficiency and/or TSH stimulation
secondary to inadequate thyroid
hormone synthesis
- may be diffuse, uninodular, or
multinodular
-compression due to very large
goiters may produce dyspnea and
dysphagia
Differential Diagnosis:
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Benign Thyroid Nodule
Thyroiditis
Lymphadenopathy
Metastasis from head and neck
cancer
3. What work ups are needed, if
any?
• Laboratory Studies
• Thyroid function
– Perform a complete assessment of
thyroid function in any patient with
thyroid lumps.
– Higher-than-normal levels of thyroxine ,
triiodothyronine and thyroid-stimulating
hormone (TSH) may indicate thyroid
cancer.
• TSH suppression test
– Cancer is autonomous and does not
require TSH for growth, whereas benign
lesions do require TSH.
– Preoperatively, the test is useful for
patients with nontoxic solitary benign
nodules and for women with repeated
nondiagnostic test results.
– Postoperatively, the test is useful for
monitoring papillary thyroid cancer
cases.
Imaging Studies
• Chest radiography, CT scanning, and
MRI
– Not usually used in the initial workup of
a thyroid nodule, except in patients with
clear metastatic disease at presentation.
Echography
– Performed first in any patient with possible
thyroid malignancy.
– Noninvasive and inexpensive, and represents
the most sensitive procedure for identifying
thyroid lesions and for determining the
diameters of a nodule.
– Useful for localizing lesions when a nodule is
difficult to palpate or is deeply seated.
– It may be used to help direct a fine-needle
aspiration biopsy (FNAB).
FNAB
• FNAB is considered the best first-line
diagnostic procedure for a thyroid
nodule;
• FNAB is a safe and minimally invasive
procedure.
– Sensitivity of the procedure is near 80%,
the specificity is near 100%, and errors can
be diminished using ultrasonographic
guidance.
– False-negative and false-positive results
occur less than 6% of the time.
Histologic Findings
• Papillary thyroid carcinoma usually appears as a
grossly firm mass that is irregular and not
encapsulated.
• Microscopically, it is multifocal, and a net invasion of
the lymphatics may be demonstrated. Complete or
partial papillary architecture with some follicles is
present.
• The thyrocytes are large and show an abnormal
nucleus and cytoplasm with several mitoses.
• Thyrocytes may have "orphan Annie eyes," that is,
large round cells with a dense nucleus and clear
cytoplasm.
• Another typical feature of this cancer is the presence of
the psammoma bodies, probably the remnants of dead
papillae.
Staging
• The staging of well-differentiated thyroid cancers is related to
age for the first and second stages, but it is not related to
age for the third and fourth stages. In the staging protocol, T
is tumor, N is node, and M is metastasis.
• Younger than 45 years
– Stage I - Any T, any N, M0 (cancer in thyroid only)
– Stage II - Any T, any N, M1 (cancer spread to distant organs)
• Older than 45 years
– Stage I - T1, N0, M0 (cancer only in thyroid, may be found in
one or both lobes)
– Stage II - T2, N0, M0 and T3, N0, M0 (cancer only in thyroid
and >1.5 cm)
– Stage III - T4, N0, M0 and any T, N1, M0 (cancer spread
outside thyroid but not outside of neck)
– Stage IV - Any T, any N, M1 (cancer spread to other parts of
body)
3. What are the treatment options?
A.TOTAL THYROIDECTOMY
B.SUBTOTAL
THYROIDECTOMY
C.NECK DISSECTION
TOTAL THYROIDECTOMY
- 30%-87.5% of PTC involve the
opposite lobe
- 7%-10% recurrence rate in the
contralateral lobe
- Lower recurrence rate
- For earlier detection and treatment of
metastatic CA with radioactive iodine
therapy
Indications of Total
Thyroidectomy:
a.) Patients > 40 y/o with papillary or
follicular CA
b.) Patients with thyroid nodule and
history of radiation
c.) Patients with bilateral disease
SUBTOTAL
THYROIDECTOMY
- Lower incidence of complications
A. Hypoparathyroidism
B. Recurrent laryngeal nerve injury
C. Superior laryngeal nerve injury
NECK DISSECTION
- For managing lymphadenopathies
- For clinically palpable cervical nodes
(as in the case) verified by MRI or CT
scan
Management of Patient with
Papillary Thyroid CA
Management - Surgery
1. Total Thyroidectomy (TTx)
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PTA may be multifocal/bilobal
↓ incidence of local recurrence
↓ risk of anaplasia in any residual tissue
↓ incidence of distant recurrence (by
facilitating diagnosis of distant
metastasis by RAI scan)
– ↑ sensitivity of blood thyroglobulin (Tg)
levels to predict recurrence/persistence
Management - Surgery
2. Modified Radical Neck Dissection
– Removal of cervical lymph nodes
– Spares sternocleidomastoid muscle,
internal jugular vein and spinal accessory
nerve
– All tissue in the anterior triangle of the
neck from the hyoid bone to the clavicle is
removed
– Dissection along the spinal accessory
nerve is most important because this is a
frequent site of metastatic disease
Immediately Post-Op
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Wound care and analgesia
Analgesia
Monitor serum thyroglobulin
Check for any possible complications
Prep patient for RAI scan and
treatment
4-6 Weeks Post-Op
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Serum thyroglobulin determination
Radioactive Iodine Scanning and treatment
(RRA)
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Discontinue L-thyroxine 8 weeks prior to scan
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First 6 weeks of this: give synthetic T3
Remaining 2 weeks prior to scan: discontinue T3 and
recommend low iodine diet
Place patient of L-thyroxine again after procedure
RAI scan looks for persistent/recurrent disease
RAI treatment may destroy microscopic cancer cells
↑ sensitivity of serum Tg improved during follow-up
4-6 Weeks Post-Op
• TSH Suppression
– Via L-thyroxine (which also serves as
replacement therapy for TTx)
– ↓ recurrence by ↓ growth stimulus to
any possible residual thyroid cancer
cells
– circulating TSH levels
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0.1 mU/L in low-risk patients
< 0.1 mU/mL in high-risk patients
Post-Op
• Thyroglobulin Measurement
– If patient taking L-thyroxine: < 2 ng/mL
– Otherwise: <3 ng/mL
• If > 3 ng/mL; highly suggestive of
metastasis /persistent normal thyroid
tissue, especially if TSH also rises
(eg. discontinuation of L-thyroxine as
prep for AI scan)
Long Term
• PE every 3-6 mo for 2 yrs then
annually
• Serum Tg at 6 and 12 mo then
annually
• 131I whole body scan (WBS) every
year until 2 negative scans
• Periodic ultrasound and Chest X-ray
WBS - Conventional
WBS – recombinant
thyrotropin
• Safer, effective means of stimulating 131I
uptake and serum thyroglobulin (Tg)
• For patients:
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Alternative to traditional LT4 withdrawal
Inability to generate endogenous TSH
Unable/unwilling to undergo LT4 withdrawal
Enhance the sensitivity of Tg in thyroid CA
follow-up
• Hypothyroidism is contraindicated
5. What are the possible
complications of your
treatment?
Bleeding
• Intraoperative bleeding stains the tissues
and obscures important structures.
•An unrecognized or rapidly expanding
hematoma can cause airway compromise and
asphyxiation.
• increases the risk of other anatomic
complications
•Deliberate dissection and fastidious
hemostasis are essential to prevent this
complication.
Injury to the recurrent laryngeal
nerve
•Mechanisms of injury to the RLN include complete
or partial transection, traction, contusion, crush,
burn, misplaced ligature, and compromised blood
supply.
•The consequence of an RLN injury is true vocalfold paresis or paralysis.
•Occurs in <1% of px undergoing thyroidectomy
Hypoparathyroidism
• Parathyroid glands produce parathyroid hormone (PTH),
which is intimately involved in the regulation of serum
calcium.
• Direct trauma to the parathyroid glands, devascularization
of the glands, or removal of the glands during surgery can
cause temporary or permanent shutdown, which results in
hypocalcemia.
•Rate of permanent hypoparathyroidism - <2%.
•Rate of transient hypoparathyroidism- 50%
Injury to the superior laryngeal nerve
Trauma to the nerve results in an inability to lengthen a vocal fold and,
thus, an inability to create a high-pitched sound.
Rate of injury to the external branch of the SLN - 15%
Infection
Infection was the major cause of death from thyroid surgery during the 1800s.
Today, infection occurs in less than 1-2% of all cases.
Hypothyroidism
Hypothyroidism is an expected sequela of total thyroidectomy.
should never be left untreated long enough to elicit signs and symptoms of
myxedema (eg, hair loss, large tongue, cardiomegaly).
Expect, diagnose, and promptly treat postoperative hypothyroidism.
Thank you!