Thyroidectomy

Thyroidectomy is a surgical procedure for the treatment of malignant (malignant) and benign (benign) changes in the thyroid gland, which involves removal of the entire thyroid gland. Depending on the indication, thyroidectomy can be performed as total thyroidectomy (TT; complete removal of the thyroid gland) or subtotal thyroidectomy (partial removal of the thyroid gland). In the case of unilateral thyroidectomy, i.e., complete removal of one of the two lobes of the thyroid gland, it is called hemithyroidectomy (HT) or lobectomy of the thyroid gland. If metastasis (formation of daughter tumors) is known preoperatively with involvement of the lymph nodes or if new lymph node metastases are discovered during surgery, a neck dissection (excision of all neck lymph nodes) is usually performed in addition to total thyroidectomy to remove regional lymph nodes.

Indications (areas of application)

  • Struma multinodosa – complete removal of the thyroid gland in the course of a total thyroidectomy is indicated for benign nodular goiter only if the thyroid tissue is completely nodular. Due to a high probability of recurrence, all affected thyroid tissue must be removed. However, total thyroidectomy is also used as the primary surgical treatment concept for benign nodular goiter in patients with an increased risk of recurrence, even if there is no complete involvement of the thyroid gland. However, due to the increased complication rates of total thyroidectomy, subtotal thyroidectomy is used as a standard procedure.
  • Graves’ disease (form of hyperthyroidism (hyperthyroidism) caused by autoimmune disease) / greater Graves’ strumen – in the treatment of Graves’ disease, there is both the option of partial removal and complete removal of the organ. Hyperthyroidism recurrence (recurrence of hyperthyroidism) is less common with total thyroidectomy than with partial thyroidectomy. However, no study has shown an advantage of total thyroidectomy over partial removal of the organ in terms of orbithopathy (pathologic change in the eye) or postoperative function.
  • Papillary thyroid carcinoma – papillary thyroid carcinoma is associated with a relatively good life expectancy of 93% in 10 years. In the treatment of carcinoma, various studies have failed to detect any difference in survival between total thyroidectomy and gentler procedures. Nevertheless, papillary thyroid carcinoma is an indication for thyroidectomy.
  • Follicular thyroid carcinoma – follicular thyroid carcinoma has a slightly lower survival rate than papillary carcinoma. Studies have also failed to show superiority of radical thyroidectomy over other procedures in this treatment. However, in the presence of distant metastases, complete removal of the thyroid gland is a necessity for successful therapy.
  • Medullary thyroid carcinoma – total thyroidectomy represents the only curative procedure for the treatment of medullary thyroid carcinoma. Based on this, any manifest medullary carcinoma is considered an absolute indication for thyroidectomy. Furthermore, the indication for prophylactic thyroidectomy is present in mutation carriers of the ret proto-oncogene in families with hereditary isolated medullary carcinoma or MEN II.
  • Anaplastic thyroid carcinoma – this type of carcinoma is associated with a poor prognosis for the patient. Despite radical surgery, a cure can be achieved only in 10%. Nevertheless, thyroidectomy represents an indication for the treatment of carcinoma within the framework of a multimodal therapeutic concept (including several therapeutic procedures).

Contraindications

Contraindications to thyroidectomy must be assessed on an individual basis. In the case of a significantly reduced general condition or inoperable tumor, the indication for thyroidectomy must be reviewed.

Before surgery

  • Preliminary examination for indication – after inspection (observation) and palpation (palpation) of the thyroid gland and sonographic imaging (thyroid ultrasound), hormone determinations and, depending on the issue, fine needle biopsies (tissue sampling) are made for further clarification.
  • Preoperative examinations – the preoperative examination is to be performed for all indications for thyroidectomy. It includes, among other things, clinical physical examination with measurement of heart rate and blood pressure. In addition, an X-ray chest examination is necessary. Furthermore, an ECG is written and a blood sample is taken to determine various laboratory parameters such as kidney parameters (urea, creatinine, creatinine clearance if necessary) and the INR determination (blood clotting), and other laboratory parameters if necessary. Other special examinations are performed depending on the indication.

The surgical procedure

First, the anterior surface of the thyroid gland is exposed so that the isthmus (tissue bridge between the two lobes of the thyroid gland) on the trachea can be cut and supplied with hemostatic bypasses. Then, the thyroid parts to be removed are detached from the surrounding area and the feeding and draining blood vessels are cut. Taking into account the location of the laryngeal recurrent nerve (vocal cord nerve) and the parathyroid glands (parotid glands), the trachea (windpipe) is approached, the connective tissue layer between the thyroid gland and the windpipe is cut, and the tissue is removed:

  • Subtotal thyroidectomy – large portions of thyroid tissue are removed, but residual tissue is left dorsally (“toward the back of the organ”); indication: struma multinodosa
  • Total thyroidectomy – the thyroid tissue is completely removed; indication: thyroid carcinoma, Graves’ disease.
  • Hemithyroidetomy – complete removal of a thyroid lobe (lobetomy); indication: unifocal autonomy (thyroid autonomy in a single nodule), singular cold nodule suspected of malignancy.

At the end of the operation, Redon drains (suction drains) are inserted. The suction pulls wound surfaces together, allowing faster adhesion and coalescence. Wound secretions (blood and serous fluid) are drained to the outside. Thyroidectomy is performed under general anesthesia (general anesthesia).

After the operation

Following the procedure, follow-up examinations must be performed to evaluate the success of the treatment and to check for possible complications. It is particularly crucial to check vocal cord mobility, as the innervating (supplying) nerve is at particular risk during surgery. The check can be performed by means of laryngoscopy (laryngoscopy) directly during anesthesia induction or by checking the speech function. If recurrent paresis is suspected, intensive medical monitoring of respiration is necessary. Furthermore, the serum calcium level must be determined postoperatively. If hypocalcemia (calcium deficiency) is present, this indicates injury or complete removal of the parathyroid gland. For optimal healing of the scar, physical exertion should be avoided during the first weeks after surgery. In case of total thyroidectomy, replacement therapy with thyroid hormones should be performed. The necessary dosage of hormone replacement is checked by a blood test after about five weeks and adjusted if necessary. Following surgery, a histopathologic (fine tissue) examination of the removed tissue is performed before the drug can be taken.

Possible complications

  • Neck pain due to positioning
  • Allergic reactions up to and including anaphylactic shock
  • Bleeding
  • Infections
  • Dysphagia (difficulty swallowing):
    • Immediately postoperative
    • After two weeks, 80% dysphagia; after six weeks, 42%; and after six months, 17%.
  • Temporary or permanent soft tissue damage or scarring.
  • Lesions (injuries) to adjacent organs such as the trachea (windpipe) or esophagus (food pipe)
  • Temporary or possibly permanent hoarseness due to a nerve lesion of the recurrent laryngeal nerve (recurrent paresis).
  • Unplanned removal of the parathyroid gland (hypoparathyroidism); postoperative hypocalcemia most common complication after total thyroidectomy (20-30% of those operated on; in the long term, 1-4% of cases)* .
  • Cardiac arrest after vagus stimulation (due tointraoperative neuromonitoring to protect the recurrent laryngeal nerve); first bradycardia (heartbeat too slow: < 60 beats per minute), then asystole (cardiac arrest; extremely rare)
  • Weight gain – despite hormone replacement, weight gain was recorded in most studies during the follow-up period of a mean of two (and a maximum of eight) years, with a mean of 2.1 kg. Patients who underwent surgery for hyperthyroidism gained the most weight. Their weight gain was a mean of 5.2 kg.

Further notes

  • In hemithyroidectomy (HT): the postoperative FT3 level is not insignificantly co-determined by the T3 production of the residual thyroid.
  • * Near infrared light (NIRAF) as an intraoperative visualization technique is expected to help in the future that the epithelial bodies light up, thus decreasing the risk of removal or hypocalcemia. One study showed that detection rates were better and fewer hypocalcemias (calcium deficiencies) occurred (four epithelial corpuscles to be detected and preserved than in the control group (47% vs. 19%); serum calcium levels dropped significantly less often below a level of 8.0 mg/dl postoperatively than in control patients (9% vs. 22%)).