Lecture 3_ carcinoma Thyroid and its surgery .pdf

This PowerPoint lecture will equip final-year medical students with a comprehensive understanding of thyroid cancers, their clinical presentation, diagnostic approaches, staging, and management strategies. The inclusion of case studies and interactive discussions will enhance their critical thinking and application of knowledge in real-world clinical settings.

1. Lecture 3

3. NEOPLASMS OF THE THYROID

8. The American Joint Committee on Cancer system
•Allpts<55yearsasstageIDistantmetastasesstageII.
•OlderT1N0M0patientsarestageIandT2N0M0patientsare
stageII.
•T1/2N1stageII,asdoesT3disease.
•Locallyinvasiveprimarydisease(T4)or
•DistantmetastasesarestageIV.

10. Cervical LN Mass
•Cancer in the neck is a metastasis from a primary lesion in
the upper aerodigestive tract
•Other primary sources are from skin, thyroid, and salivary
gland
•Lymphomas often present as cervical lymphadenopathy.

11. Clinical Evaluation
•A careful history and physical examination, along with a thorough
evaluation of the aerodigestive tract
•Fine-needle aspiration (FNA)-differentiate between epithelial and
lymphoid malignancies.
•Sensitivity of FNA ranges from 92 to 98%
•Specificity from 94 to 100%.

12. FNAC Report
•Lymphoid –Excisional Biopsy
•Epithelial –Panendoscopy
•Indeterminate –Excisional Biopsy

18. Contraindication –Unresectable Tumours
•Horner syndrome,
•Paralysis of the vagusnerve
•Phrenic nerve,
•Brachial plexus
•Prevertebral muscles
•Carotid artery

19. Comprehensive Dissection:
Radical Neck Dissection
•1906 by George Crile, -Halstedianprinciple of enbloc resection.
•Lymphatic structures from the strap muscles anteriorly, the trapezius
posteriorly, the mandible superiorly, and the clavicle inferiorly are
removed.
•Nonlymphaticstructures the spinal accessory nerve, the
sternocleidomastoid muscle, the internal and external jugular veins,
the submandibular gland, and sensory nerve roots.

20. Modified Radical Neck Dissection
•Type I -the spinal accessory nerve;
•Type II, the spinal accessory nerve and the internal
jugular vein;
•Type III, both of these structures, along with the
sternocleidomastoid muscle.

21. Other types
•Selective Neck Dissection
•Extended Neck Dissections
•Bilateral Neck Dissections
•Neck dissection after chemoradiation

23. RADICAL NECK DISSECTION
•Step 1: Incision and Flap Elevation
•Subplatysmal flaps are raised
•The flaps are raised to the mandible superiorly, the
clavicle inferiorly, the omohyoid muscle and the
submental region anteriorly, and the trapezius
posteriorly.

25. Step 2:
Dissection of
Anterior
Compartment

26. Step 2: Dissection of Anterior Compartment
•The marginal mandibular branch of the facial nerve, which must
be elevated and retracted to prevent lower-lip weakness.
•The submental fat pad is then grasped, retracted posteriorly and
laterally, and mobilized away from the floor of the submental
triangle.
•The omohyoid muscle is identified inferior to the digastric tendon
and followed inferiorly to the sternocleidomastoid muscle.
•The omohyoid muscle forms the anteroinferior limit of the
dissection.

27. Step 2: Dissection of Anterior Compartment
•Distal end of the facial artery can be identified and preserved
•Once the posterior edge of the mylohyoid muscle is
visualized, an Army-Navy retractor is inserted beneath the
muscle to expose the submandibular duct, the lingual nerve
with its attachment to the submandibular gland, and the
hypoglossal nerve.
•The submandibular duct and the submandibular ganglion,
with its contributions to the gland, are ligated, and the
submandibular gland is retracted out of the submandibular
triangle.

28. Step 2: Dissection of Anterior Compartment
•Often the hypoglossal nerve is surrounded by a plexus
of small veins, branching off the common facial vein.
•The jugular vein, located just posterior to the external
carotid artery and the hypoglossal nerve, may be
isolated and doubly suture-ligated at this point.
•Frequently, the spinal accessory nerve is identified just
lateral and posterior to the internal jugular vein,
proceeding posteriorly into the sternocleidomastoid
muscle

29. Step 3: Control of Internal Jugular Vein
Inferiorly;
Ligation of Lymphatic Pedicle

30. •The sternal and clavicular heads of the sternocleidomastoid
muscle are transected and elevated to expose the anterior belly of
the omohyoid muscle.
•The soft tissue overlying the posterior belly of the omohyoid
muscle is clamped and ligated as necessary.
•The omohyoid muscle is then transected, and the jugular vein, the
carotid artery, and the vagusnerve are exposed.
•The jugular vein is isolated and doubly suture ligated. Care is
taken not to transect the adjacent vagusnerve and carotid artery.

31. •The lymphatic tissues in the base of the neck adjacent to the
internal jugular vein are clamped and suture-ligated 1 cm
superior to the clavicle.
•If a chyle leak is encountered, a figure-eight stitch is placed
along the lymphatic pedicle until there is no evidence of clear
or turbid fluid on the Valsalva maneuver.
•Care is taken to avoid inadvertent injury to the vagusnerve or
the phrenic nerve, which course through this region.

32. Step 4: Mobilization of SupraclavicularFat
Pad (“Bloody Gulch”)
•The fascia overlying the supraclavicular fat pad is incised,
and the supraclavicular fat pad is bluntly retracted superiorly
so as to free the tissues from the supraclavicular fossa.
•If transverse cervical vessels are encountered, they are
clamped and ligated as necessary.
•Fascia is left on the deep muscles of the neck, which also
envelop the brachial plexus and the
•phrenic nerve.

33. Step 5: Dissection and Removal of Specimen
•Fat and lymphatic tissues are retracted anteriorly with Allis clamps, and the specimen is dissected off the
deep muscles of the neck with a blade.
•a layer of fascia is left on the deep cervical musculature: stripping fascia off the deep cervical musculature
results in denervation of these muscles, which adds to the morbidity associated with accessory nerve sacrifice.
•Once the specimen is mobilized beyond the phrenic nerve, the cervical nerves (C1–C4) may be divided. The
specimen is peeled off the carotid artery and removed.

34. Step 6: Closure

35. Modified Radical Neck
Dissections
Type 1
Type II
Type III

36. Selective Neck Dissections
LEVEL I –IV
LEVEL II -IV

38. Step 2:
Dissection of
Anterior
Compartment

39. Complications

40. •Neck dissections are considered either therapeutic (performed to remove clinically identifiable cancer in the
neck) or elective (performed when the expected incidence of occult metastases from a lesion exceeds 20%).
•In patients with head and neck cancer, neck dissection may be performed as part of initial definitive treatment,
often combined with resection of the primary cancer.
•Alternatively, neck dissection may be performed in an adjuvant setting to remove residual cancer in the neck
following treatment with radiation or chemoradiation