How best to avoid revision thyroid surgery

Measures to avoid revision thyroid surgery are of major importance and can be applied to benign or malignant problems. During the initial surgical procedure for benign nodular goiter, the most common surgical procedure used to be subtotal thyroidectomy. However, our current understanding from long-term follow-up of previous patients who underwent subtotal thyroidectomy shows a high incidence of recurrent nodular goiter. Reeve and colleagues from Australia reported an incidence of 22% for recurrent nodular goiter. A total thyroidectomy for bilateral nodular disease would avoid the need for reoperative thyroid surgery. Even though the extent of surgery for nodular goiter continues to be debated, the current philosophy is to consider total thyroidectomy in the presence of bilateral thyroid nodularity. The preoperative ultrasound has changed the approach in initial thyroid surgery. If the contralateral lobe has nodular disease, the best decision would be to consider total thyroidectomy, whether the preoperative indications are benign, suspicious, or malignant pathology. Even though differences of opinion exist about the surgery for a solitary thyroid nodule, if the contralateral lobe does show thyroid nodularity, it would be best to consider total thyroidectomy because follow-up of the contralateral thyroid nodule can be complex. A future increase in the size of the thyroid nodule seen on ultrasound or a suspicious or atypical fine needle aspiration biopsy would force the surgeon to perform a completion thyroidectomy. If the surgeon is aware of the diagnosis of malignancy in a thyroid nodule before the initial surgical procedure, it is most important to make a decision about the extent of thyroidectomy based on the gross extent of the disease, poor prognostic features, status of the lymph nodes in the central compartment, extent of the ipsilateral thyroid disease, and whether radioactive iodine ablation is needed . If the patient is likely to require radioactive iodine ablation, the best surgical procedure would be total thyroidectomy as the initial procedure. When a patient presents with a thyroid nodule and he/she belongs to a low-risk group having undergone ipsilateral thyroid lobectomy, the major debate continues as to whether completion thyroidectomy is needed. The subject of completion thyroidectomy not only is a major controversy but also, to some extent, generates a knee-jerk reflex among thyroid surgeons and patients. Most surgeons and endocrinologists routinely recommend completion thyroidectomy if the ipsilateral thyroid cancer is greater than 1 cm. However, neither good statistical evidence nor prospective studies exist for patients who have undergone ipsilateral thyroid lobectomy for minimally invasive thyroid carcinoma. The past 2 decades have taught us much about prognostic features and risk group analysis in patients who have well-differentiated thyroid carcinoma. These prognostic features are universally accepted, and include as age, grade of tumor, extrathyroidal extension, size (AGES); age, distant metastasis, extrathyroidal extension, size of tumor (AMES); grade, age, distant metastasis, extrathyroidal extension, size (GAMES); and distant metastasis, age, completeness of thyroid resection, invasion, and size of the tumor (MACIS). These prognostic features divide patients who have well-differentiated thyroid cancer into low, intermediate, and high risk. The overall outcome in low-risk thyroid cancer exceeds 98%. Caution should be entertained in routinely advising completion thyroidectomy for low-risk thyroid cancer. The complications of reoperative thyroid surgery may be much worse than the disease itself. This possibility needs to be recognized by surgeons, endocrinologists, and patients. Advising a completion thyroidectomy should be based on the biology of the disease and the extent of the initial surgical procedure.

Revision thyroid surgery for Graves’ disease is one of the most challenging subjects for the thyroid surgeon. Even though the initial extent of surgery for Graves’ disease is debated, generally, most thyroid surgeons today would consider performing total thyroidectomy, rather than subtotal thyroidectomy with the risk for leaving behind a tiny remnant of thyroid tissue that may cause recurrent hyperthyroidism, or they would treat patients with radioactive iodine ablation. The residual thyroid tissue may be so small and scarred that identifying and performing a completion thyroidectomy would be difficult, with high risk for nerve and parathyroid injury. Such patients would be better treated with radioactive iodine than with surgery.

During the initial surgical procedure, the central compartment should be evaluated routinely. Even though, paratracheal clearance during thyroid surgery is debated, a preoperative ultrasound is helpful when making decisions. If the jugular chain contains obvious suspicious lymph nodes, a modified neck dissection should be considered . In every patient undergoing surgery for suspected or proven thyroid cancer, central compartment evaluation is important. If any suspicious lymph nodes exist, then central compartment dissection should be performed. However, routine central compartment dissection is best avoided, because microscopic nodal disease has not been implicated in long-term survival and the incidence of complications related to permanent hypoparathyroidism is high in patients undergoing routine central compartment dissection.

The common indications for revision thyroid surgery

One of the most common indications for completion thyroidectomy is ipsilateral thyroid disease reported as benign on frozen section ( Table 1 ). The frozen section has limited value during thyroid surgery. Minimally invasive follicular carcinoma and the follicular variant of papillary thyroid carcinoma may be difficult to interpret in a frozen section during surgery for a solitary thyroid nodule. Decisions regarding completion thyroidectomy should be based on the extent of the initial disease, along with the prognostic features and risk group analysis. Even though the debate continues about completion thyroidectomy in patients who have low-risk thyroid cancer, certain indications are important to consider for completion thyroidectomy. These indications are

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  Size greater than 4 cm

  
  
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  Major capsular or vascular invasion

  
  
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  Histologic features of tall cell, undifferentiated, insular, or trabecular thyroid carcinoma

  
  
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  Extra thyroid extension

These indications for completion thyroidectomy need to be weighed against the difficulties in the initial surgical procedure and whether the ipsilateral recurrent laryngeal nerve was injured. If a recurrent laryngeal nerve is paralyzed during the initial surgical procedure, the enthusiasm for a completion thyroidectomy must be weighed against the risk/benefit ratio. Any injury to the contralateral recurrent laryngeal nerve may lead to permanent tracheostomy.

The other common indication for reoperative thyroid surgery is postoperative hematoma. Postoperative bleeding occurs in 1% to 2% of patients undergoing thyroid surgery . Even though the reason for wound hematomas is not clearly determinable, the common cause is excessive coughing and retching or a loose tie on a major feeding vessel. Most wound hematomas occur in the first 24 hours, and debate continues as to whether the patient should be sent home on the day of surgery. Most surgeons are reluctant to send the patients home on the day of surgery for fear of bleeding, especially in the middle of the night. Bleeding can lead to considerable swelling in the neck, and airway distress. After thyroid surgery, the patient should be closely observed in the recovery room, and any expanding hematoma is a dire emergency. The wound should be opened bedside to relieve airway distress and airway compression. The patient should be brought back to the operating room for re-exploration. The wound should be irrigated, the hematoma evacuated, and any bleeding vessel securely ligated. Postoperative wound hematoma can be a life-threatening emergency, and recovery room nurses and residents should be aware of emergency evacuation of hematoma and measures to avoid airway catastrophe. Occasionally, if the airway cannot be secured, the patient may require a crash tracheostomy, which can be easily performed because the trachea has already been exposed during thyroid surgery.

The issue of routine wound drainage after total thyroidectomy is essentially resolved by the many randomized prospective studies showing no specific benefit to routine drainage after thyroid surgery . Approximately 75% to 80% of all thyroid surgeries do not require drainage. The major indications for wound drainage after thyroid surgery are large goiters, substernal goiter with a large dead space, extensive dissection or considerable oozing after thyroid surgery, or subtotal thyroidectomy with oozing thyroid surface. A closed suction drain is routinely used after thyroid surgery, if indicated. In most cases, the drain can be removed within 24 to 48 hours; however, it does delay discharging most of the patients until 48 hours after surgery.

Recurrent nodular goiter after previous subtotal thyroidectomy is another major indication for reoperative thyroid surgery, even though today, the incidence of this indication is low. One of the most common surgical procedures used to be a subtotal thyroidectomy for nodular goiters. Now, generally, a total thyroidectomy is considered if the patient presents with nodular goiter on both sides. It may be difficult in practice to identify normal thyroid tissue in a patient who presents with a colloid goiter. The remaining thyroid tissue may not be enough to function for the patient’s thyroid hormone needs. However, with a massive goiter, a subtotal thyroidectomy may be considered if identifying the recurrent laryngeal nerve and parathyroid glands is difficult. Often, in patients who have a massive nodular goiter, total thyroidectomy is much easier and less bloody than subtotal thyroidectomy. Similar issues are entertained in surgery for Graves’ disease and recurrent Graves’ disease. With recurrent Graves’ disease, the reoperative surgery may be more difficult because of considerable scarring, fibrosis, and tiny remnant thyroid tissue.

Another major indication for reoperative thyroid surgery is the appearance of a thyroid nodule in the contralateral lobe after a patient has undergone ipsilateral lobectomy. The routine use of ultrasonography in follow-up is more likely to detect tiny nodules in the contralateral lobe, which may raise a question as to whether we are dealing with a thyroid cancer or a benign pathology. A fine needle aspiration biopsy may show atypical cells, and the patient will require completion thyroidectomy. The incidence of microscopic thyroid cancer in the contralateral lobe is approximately 30% to 60%, depending on the intensive evaluation by the pathologist with serial subsectioning of the thyroid tissue . During the initial surgical procedure, it is important to evaluate the opposite lobe clinically and with a preoperative ultrasound. If a thyroid nodule in the contralateral lobe is suspected, the best initial surgical procedure would be total thyroidectomy, rather than follow-up of a tiny nodule in the opposite lobe. This tiny nodule could represent papillary carcinoma, despite a negative needle biopsy.

One of the most challenging indications for reoperative thyroid surgery is locally recurrent thyroid cancer in the thyroid bed . The reasons for recurrent thyroid cancer need to be studied before surgical intervention. These reasons can be complex and related to the initial surgical procedure with locally advanced thyroid cancer. The extent of the initial disease needs to be recognized, as well as the involvement of surrounding structures such as the recurrent laryngeal nerve, tracheal wall, esophageal musculature, or strap muscles. If the initial surgical procedure was unsatisfactory and all gross tumor was not removed, the second surgical procedure is going to be a challenge in relation to functioning vital structures such as recurrent laryngeal nerve and tracheal wall. If the tumor is adherent to the tracheal wall, the exact extent of the disease needs to be evaluated preoperatively and intraoperatively. If the submucosa of the trachea or the tracheal lumen is clearly involved, the patient will require appropriate tracheal resection (sleeve resection and a primary anastomosis). However, if the tumor is adherent to the tracheal wall, in most cases it can be shaved off the trachea carefully. Most of these patients will require adjuvant therapy in the form of radioactive iodine ablation or external radiation therapy, depending on the grade of the disease and the features of poorly differentiated thyroid cancer. The preoperative evaluation must include indirect laryngoscopy or fiberoptic laryngoscopy to evaluate the function of the vocal cords. If the ipsilateral nerve is paralyzed, any surgical procedure must be weighed against the risk for injury to the contralateral recurrent laryngeal nerve. The initial operative notes should be studied seriously and, if possible, discussion should be entertained with the previous operating surgeon regarding the gross operative findings at the time of the initial procedure. The pathology slides should be rereviewed to evaluate whether this carcinoma was truly a well-differentiated thyroid carcinoma or another form, such as tall cell, insular, or poorly differentiated. Appropriate preoperative evaluation with imaging studies such as endoscopy, ultrasonography, CT scan, or positron emission tomography (PET) scan will be helpful in properly evaluating the extent of disease. The goal of surgery in locally recurrent thyroid cancer should be to remove all gross tumor. The surgeon must be prepared to resect the structures directly involved by the tumor, which may require tracheal resection, resection of the central compartment soft tissue, strap muscles, or esophageal musculature. If the tumor is directly invading the esophageal musculature and mucosa, the patient may require esophageal resection, which may necessitate total laryngectomy and resection of the cervical esophagus with appropriate reconstruction, either by gastric pull-up or free microvascular jejunal interposition. Recurrent thyroid cancer in the thyroid bed requires a thorough preoperative evaluation, appropriate intraoperative decisions, and preparedness of the operating surgeon and the patient to undertake appropriate surgery to avoid further recurrence in the central compartment. Most deaths from thyroid cancer still occur because of central compartment recurrence, especially found in older individuals and those who have poor histologic features. Any recurrence after reoperative surgery would be difficult to handle, and the mortality rate for these patients is high.

Today, one of the most common indications for reoperative thyroid surgery is paratracheal, jugular, or lateral neck nodal recurrence. This recurrence is commonly recognized because of routine follow-up of patients with ultrasonography of the neck, which is likely to detect tiny paratracheal lymph nodes. A fine needle aspiration biopsy may show papillary thyroid carcinoma. Occasionally, a needle wash is considered to detect the presence of thyroglobulin, which is indicative of metastatic papillary carcinoma of the thyroid. Whether all of these patients truly need to be operated on is a subject of debate. As operating surgeons gain more experience in this kind of operative surgery, they soon recognize the high incidence of complications and the possibility of future recurrence. The surgeon and the patient must realize that the operative procedure may not be over, and the patient may return with additional paratracheal, jugular, or lateral neck nodes, the thyroglobulin levels may never become normal (as decrease in the thyroglobulin level is seen only in 30% of the individuals), and the possibility exists of future recurrent disease in the thyroid bed, paratracheal area, or contralateral neck. If the nodal recurrence is less than 1 cm, the author usually continues to monitor the patient closely and repeat serial ultrasounds at intervals of 6 to 12 months. If the size of the nodal recurrence shows no major change, he is comfortable following the patient as long as the initial histology is well-differentiated thyroid carcinoma. A PET scan may be helpful in deciding which patients may need prompt surgical intervention versus observation. PET-positive disease is unlikely to respond to radioactive iodine ablation. Some recent interest appears to exist in radiofrequency ablation or alcohol injection in the nodal recurrence; however, experience is currently limited and long-term results from these interventions are not well studied.