Total thyroidectomy for the treatment of thyroid diseases in an endemic area.

Introduction: Thyroidectomy is a common operation with very low mortality and an acceptable morbidity rate. Total thyroidectomy has become the predominant type of surgery used today for the treatment of thyroid diseases. In this retrospective study, we analyzed the complications of thyroid surgery according to the operative technique used in our department.

Material and Methods: A retrospective analysis was performed for all patients who underwent thyroid surgery during the previous 11 years. The period under study was divided into two sections: phase A (1995-1999) and phase B (2000-2005). Patient characteristics, type of operation, histologic diagnoses and postoperative complications were compared in the two study periods according to the type of surgery.

Results: A total of 264 patients between the ages of 18 and 89 underwent thyroid surgery during the study period (133 in phase A and 131 in phase B). Overall histopathological diagnoses were nodular goiter (54.9%), hyperplastic nodules (14.7%), adenoma (8.3%), thyroid cancer (18.2%), and Hashimoto thyroiditis (3.8%). Total thyroidectomy was performed in 91 patients in phase A versus 115 patients in phase B (P < 0.001), whereas the use of subtotal thyroidectomy and lobectomy decreased over time. A trend toward increased morbidity was noted in phase B. Seven patients had hypocalcemia in phase A, whereas 11 patients had hypocalcemia in phase B. Similarly, 5 patients had some degree of vocal cord paralysis in phase A, compared with 7 in phase B (P > 0.05). Morbidity was significantly increased in the case of cancer or reoperation.

Conclusion: Despite the slightly higher risk of complication associated with total thyroidectomy, this has gradually replaced more conservative approaches for the treatment of both benign and malignant thyroid diseases. Reoperations and surgery for thyroid cancer carried a higher risk of complications.

Key Words: thyroid, surgery, goiter, cancer, thyroidectomy

**********

Thyroid diseases affect more than 15% of the general population in endemic areas. (1) Several areas of Greece are still considered endemic, since a greater than average percentage of the population is affected. Despite the correction of iodine deficiency in most areas, endemic goiter still persists in regional areas, indicating the additional pathogenetic role of genetic factors and/or naturally occurring goitrogens. (2,3) The reasons for removing all or part of the thyroid may be an enlarged thyroid gland that is pressing on structures in the neck, especially if it causes problems with breathing and swallowing, an undiagnosed thyroid mass and a malignant (cancerous) thyroid tumor. Also, the thyroid gland may be surgically removed for overactive thyroid (hyperthyroidism) unresponsive to medical treatment or in pregnant women. Several modes of treatment have been described for the surgical management of these diseases, including excision of the lesion, thyroid lobectomy when one entire lobe is removed, subtotal thyroidectomy and total thyroidectomy. Thyroidectomy is a common operation with extremely low mortality and a low rate of complications. Total thyroidectomy has become the standard procedure for the treatment of thyroid carcinoma, multinodular goiter and Graves disease. However, it is associated with specific complications (13%) related to the surgeon's experience. (4,5) The most frequent complications are recurrent laryngeal nerve injury, (5-7) superior laryngeal nerve injury, (8,9) and postoperative hypoparathyroidism. (10-12) Other complications include postoperative hemorrhage--a rare but dangerous complication, wound infection and hypothyroidism. (4,5,9)

However, with improving surgical technique, total thyroidectomy can now be performed with a minimal surgically related complication rate and an almost null risk of disease recurrence in the long term. (13,14) This paper reports on the clinical audit of thyroid surgery undertaken at the 3rd Department of Surgery of the University of Athens Medical School. The complications following the various types of thyroidectomy are highlighted and compared with published data. In addition, differences in surgical strategy and techniques during the study period are also analyzed.

Methods

All patients who underwent thyroidectomy between January 1995 and September 2005 in the 3rd Department of Surgery of the University of Athens Medical School were included in the audit. The demographic characteristics of all these patients including history, age and gender were reviewed. All patients were evaluated by means of physical examination, thyroid function tests, thyroid ultrasonography and scintigraphy. Antithyroid medications were administered for hyperthyroidism for two to three weeks before surgery to attain a euthyroid state. Fine-needle aspiration biopsy was required for hypoactive and dominant thyroid nodules. Preoperative and postoperative levels of calcium and phosphorus were evaluated. The type of thyroidectomy, either unilateral lobectomy, subtotal thyroidectomy or total thyroidectomy, was reported. About 50% of the patients were operated on by three senior general surgeons and the remaining 50% by residents under close supervision of a senior surgeon. The surgical reports and the pathologic characteristics of the resected thyroid tissue were reviewed. During the operation, the recurrent laryngeal nerve was always identified and traced to the cricoid cartilage on both sides. Every possible effort was taken for the parathyroid glands to be identified and preserved with their blood supply. After the operation, all patients underwent ear/nose/throat (ENT) laryngoscopy assessment. We reported transient or definitive paralysis of one or both vocal cords and transient or permanent hypoparathyroidism. Permanent vocal cord palsy was defined as continued postoperative vocal cord paralysis 6 months after surgery. Transient vocal cord paralysis usually was evident with hoarseness of voice for a few days. Similarly, patients requiring more than 6 months of calcium or vitamin D supplementation for postoperative hypocalcemia were defined as suffering from permanent hypoparathyroidism. Other complications such as intra- and postoperative hemorrhage and lesions of the superior laryngeal nerve were also recorded.

For a thorough analysis of our results, we divided the period under study into two periods: phase A (1995-1999) and phase B (2000-2005). Patients' characteristics, type of operation, histologic diagnoses and postoperative complications were compared in the two study periods. The [X.sup.2] test was used for statistical comparisons of data between the two phases.

Results

Comparison Between Phase A and Phase B

A total of 133 patients (103 women, 30 men) underwent thyroidectomy in phase A (1995-1999) and 131 patients (108 women, 23 men) underwent thyroidectomy in phase B (2000-2005). The distribution of age was similar in both phases (Table 1). The use of total thyroidectomy increased during the second period; 91 patients (68.4%) in phase A versus 115 patients (87.8%) in phase B (P < 0.001). On the contrary, the use of subtotal thyroidectony and lobectomy was substantially decreased during the second period. Thus, 28 patients (21%) underwent subtotal thyroidectomy and 14 (10.6%) underwent lobectomy in phase A, whereas 11 patients (8.4%) underwent subtotal thyroidectomy and 5 (3.8%) underwent lobectomy in phase B (P < 0.01 and P < 0.001, respectively for the two types of surgery).

Regarding the histopathological diagnosis, the distribution was similar in the two phases. A trend toward increased morbidity in phase B was observed, however, when total thyroidectomy was predominantly used, compared with phase A. Thus, 9 patients (6.8%) had transient hypocalcemia in phase B, compared with 5 patients (3.8%) in phase A. Also 2 patients (1.5%) were found to have permanent hypocalcemia in phase A, and 2 patients (1.5%) developed permanent hypocalcemia in phase B. The most common clinical manifestation of postoperative hypocalcemia was acral numbness and paresthesia. Other symptoms present included oral paresthesia and generalized muscle cramps. Only 2 patients (one in each phase) presented with tetany. Hypocalcemia (either transient or permanent) was more frequently encountered after total thyroidectomy (12 cases) than after subtotal thyroidectomy (4 cases) or lobectomy (2 cases); however, differences were not statistically significant (Fig. 1).

Two patients (1.5%) had permanent vocal cord palsy, and 5 (3.8%) had transient vocal cord palsy in phase B, whereas one patient (0.75%) had permanent vocal cord palsy and 4 (3%) had transient in phase A. However, none of the complications were considered statistically significant (P > 0.05). Vocal cord palsy (either transient or permanent) was more frequently encountered after total thyroidectomy (8 cases) than after subtotal thyroidectomy (4 cases) or lobectomy (0 cases); however, differences were not statistically significant (Fig. 2). Two patients (1.5%) experienced superior laryngeal nerve injury in phase A. These patients had difficulty ingesting liquids. One patient in phase A had a wound infection after surgery. One patient with a medullary carcinoma died in phase B, one month after surgery, due to brain metastases, for an overall mortality rate of 0.37%.

Thyroid Cancer

A total of 48 patients (18.1%) with thyroid cancer underwent surgery during the study period. Papillary carcinoma comprised the majority of cases (42 patients, 15.9%), follicular carcinoma was diagnosed in 5 cases (1.9%) and medullary carcinoma was present in one case. The extent of surgery ranged from hemithyroidectomy (lobectomy plus isthmectomy) to total thyroidectomy plus central compartment lymph node dissection (Table 2). Total thyroidectomy with/without central compartment lymphadenectomy was used more often than other procedures in the second phase of the study for the treatment of cancer (P < 0.001). The risk of hypoparathyroidism after thyroidectomy was higher in cancer patients. Ten patients with cancer (20.8%) had postoperative hypocalcemia, which is an extremely significantly increased percentage compared with patients operated on for benign conditions (P < 0.00001). Two of ten patients developed permanent hypoparathyroidism and required lifelong calcium supplementation with oral calcium and vitamin D3. After discharge, all cancer patients were followed up by the Division of Endocrinology at our hospital. They all underwent iodine [I.sup.131] ablation after surgery. All but one patient (who developed myeloid carcinoma) are alive and in good condition 71 [+ or -] 46.6 months after surgery.

[FIGURE 1 OMITTED]

[FIGURE 2 OMITTED]

Reoperations

Reoperative thyroid surgery was required in 10 patients after the primary thyroid operation (3.7%). All but one of these patients had been operated on in other centers. Diagnoses included multinodular goiter in 3 patients and cancer in 7 patients. Morbidity from the reoperative thyroid surgery was significantly higher than the primary surgical procedure (P < 0.05). Postoperative complications following reoperative thyroid surgery were seen in 4 patients (40%); the incidence of complications after primary thyroid surgery was 12.20% (31/254). One patient experienced hoarseness of voice with permanent recurrent laryngeal nerve palsy, 2 had postoperative permanent hypocalcemia and one had superior laryngeal nerve injury.

Discussion

All patients who underwent thyroidectomy between January 1995 and September 2005 in our clinic were included in the study. The proportion of histopathological diagnoses, including malignant cases, remained constant throughout the study period. On the other hand, the type of surgery used revealed a change during the years. Before 1999, the preferred surgical approach was lobectomy or subtotal thyroidectomy, whereas in the second phase of the study, these types of surgery were replaced by total thyroidectomy. Nevertheless, a trend toward increased morbidity was noted in phase B. However, the benefits of total thyroidectomy seem to outweigh the slightly increased morbidity associated with the procedure. Total thyroidectomy allows a more thorough substitution of thyroid function with thyroxine tablets and prevents recurrence of the disease. Also, in case of cancer, total thyroidectomy will remove residual tumor in the remaining contralateral lobe of the thyroid gland in 43% of patients. In addition, this type of surgery allows the patient to be scanned for residual thyroid remnant and distant metastases. (15) Mazzaferri et al (16) showed that surgery that was more extensive than lobectomy improved survival in persons who had papillary and follicular cancers and no distant metastases. Rossi et al (17) studied patients with surgically incurable thyroid cancer and found improved long-term survival after extensive resection of thyroid tissue and removal of obvious lymph node metastases. A more thorough thyroidectomy was recommended for carcinoma because more than 40% of patients treated with initial lobectomy or partial lobectomy may require a second operation. (18) Even for diffuse multinodular goiter, the thyroidectomy should be extensive because the rate of recurrence is greater than 10% after 10 years, and this is related to the size of the thyroid remnant. (19) Simple excision of a nodule or unilateral lobectomy is no longer recommended for primary thyroid surgery. For the above reasons, total thyroidectomy has become the procedure of choice for both benign and malignant thyroid diseases in most endocrine surgical units worldwide.

Complications of thyroidectomy are largely related to the magnitude of the operation and the experience of the surgeon involved. (4,5) Patients are observed for up to 72 hours after thyroid surgery to guard against the potentially fatal complications of airway compromise, hemorrhage and severe hypocalcemia. Seventy-five percent of life-threatening complications occur within 6 hours of operation, and the remainder is seen between 7 and 24 hours. (20)

Morbidity after reoperative thyroid surgery is markedly increased. The incidence of complications after reoperative thyroid surgery in this series was 40% (4/10), a statistically increased percentage compared with complications after primary thyroid surgery. The incidence of complications after reoperative thyroid surgery varies from center to center. Recurrent laryngeal nerve injury has been reported after secondary thyroidectomy in between 1.5% to 7.9% of patients overall, whereas hypoparathyroidism has been reported to occur in between 1.6% to 11.2% of patients. (16-22) The incidence of recurrent laryngeal nerve injury noted in our study was 10% and permanent hypoparathyroidism was 20%. Complications are common in the reoperative setting because of extensive scarring, distortion of typical dissection planes and anatomic relationships, and proximity of the disease that necessitates reoperation to the recurrent laryngeal nerve. Because of the definitely increased morbidity in reoperative thyroid surgery, radioiodine ablation treatment of the thyroid remnant to replace completion thyroidectomy was suggested. (23,24)

The overall incidence of permanent recurrent laryngeal nerve paralysis after thyroidectomy in this series was 1.1%. This is in accordance with incidences reported elsewhere (0.1%-5.2%). (24-27) The work of Lo et al (28) suggests that most recurrent laryngeal nerve injuries are not recognized intraoperatively by the surgeon. The Wagner and Seiler (29) study showed that thyroid carcinoma, Graves disease, thyroiditis and recurrent goiter have a 3 or 4 times greater risk of nerve damage than that for euthyroid nodular goiter and adenoma. Also, trauma to this nerve is more likely if there are variations or distortions of anatomy, previous radiation or revision surgery. (8) Transient paralysis is usually associated with stretching, inflammation and postoperative edema. (29,30) The recurrent laryngeal nerve injury manifests with hoarseness or change in quality of voice or with evidence of vocal cord paralysis documented by laryngoscopy. (24) It is considered the most serious complication of thyroidectomy because it deeply influences the patient's social life. It is important to start logopedic rehabilitation early (within 2-3 week) in cases of vocal cord paralysis. (31) Several authors propose various options, and therefore different techniques are used. It might be preferable to save some thyroid tissue around the nerve junction to the larynx or to perform a capsular dissection. (31-33) In addition, visual identification of the recurrent laryngeal nerve during thyroid surgery has been shown to be associated with better outcome than other methods of nerve avoidance during thyroidectomy. (34-38)

Recurrent laryngeal nerve is not the only nerve that may be injured during the operation. The external branch of the superior laryngeal nerve is also at risk during thyroidectomy. Superior laryngeal nerve injury manifests as a lower voice tone, vocal fatigue, and difficulty singing note intonation. (31) If an ipsilateral superior laryngeal nerve lesion is present, dysphagia to liquids often occurs. It is caused by impaired coordination of glottis closure by the epiglottis, which determines liquid inhalation in the airway. Even if dysphagia regresses in a few weeks, sometimes it is so severe it compromises adequate hydration. Such injury may be minimized if the nerve is identified and preserved during ligation of the upper pole vessels. (39,40)

Postoperative hypocalcemia is sometimes encountered after thyroidectomy and is known as a major cause of postoperative morbidity in patients who have undergone thyroidectomy. The results of our retrospective study showed that calcium levels dropped after thyroidectomy in 18 patients (6.81%). This decrease in calcium levels might have resulted from hypoparathyroidism due to removal and/or ischemia of the parathyroid tissue. Calcium levels do not always decrease immediately after thyroidectomy, often taking up to 24 to 72 hours to reach a nadir. (41) Transient hypocalcemia occurred in 5.3% of patients overall in the current series, whereas permanent hypocalcemia occurred in 1.51%. Permanent hypocalcemia has been reported to occur in 0.1 to 32% of cases. (1,4,5,26,28,42-44) These reported incidence figures are in concordance with the incidence of hypocalcemia seen in this series. The problem of how many parathyroids must be preserved to maintain a normal serum calcium level remains unresolved. Most authors believe that a single functioning gland is enough to restore normal parathyroid activity, whereas others believe that the integrity of at least three glands is necessary. (45,46) The risk of permanent hypocalcemia is higher for cancer surgery and ranges from 3 to 32%. (28,43,44) In our study, the incidence of hypoparathyroidism after surgery for cancer was 16.6%. Malignancy may be a predictor of postoperative hypocalcemia. Surgery for malignant disease may be more extensive than surgery for benign disease and may have a greater likelihood of injury to the parathyroid glands or their blood supply, leading to hypocalcemia. McHenry et al (47) performed an analysis to identify predictors of postoperative hypocalcemia. They concluded that increased preoperative T4 levels, carcinoma and the presence of substernal thyroid extension correlated with postoperative hypocalcemia. Recent studies have evaluated parathyroid hormone (PTH) levels as a predictor of hypocalcemia within the first few days after thyroid surgery. Richards et al (48) investigated patients by monitoring PTH and serum calcium levels and the onset of symptomatic hypocalcemia. They found that patients with PTH levels that decreased below the reference range at the end of the surgery tended to develop symptomatic hypocalcemia in the first 24 to 48 hours after surgery. This subset of patients should be treated aggressively before such symptoms develop. Tetany and paresthesia, such as tingling around the mouth and in the distal extremities, are commonly seen in hypocalcemia. The appearance of these symptoms is thought to be related to the degree or speed of calcium level reduction after thyroidectomy and to the extent of the surgical procedure. Other factors that determine the variation in frequency and severity of symptoms include acid-base status and hypomagnesemia. (10,49) Postoperative short-term calcium supplementation was given to 16 patients and 1,25-dihdroxyvitamin D3 was given to 5 patients, for a duration of a few days to six months. Medication was discontinued as soon as patients were found to be normocalcemic after surgery. Long-term supplementation of vitamin D3 was required in only 4 patients who had permanent hypoparathyroidism. We have to avoid unnecessary calcium supplementation because this may cause hypercalcemia and hypercalciuria, which could result in renal failure. (50)

Infections following thyroid surgery are rare and have a low incidence: 0.37% in our study. Therefore, the use of antibiotics is justified only when patients manifest severe diabetes, immunodeficiency or valvular heart disease. Disinfection and cleaning of the skin must be absolute. Hypothyroidism after total thyroidectomy is considered an expected result. Hence, it is not a complication if we consider that total thyroidectomy has its own logic. Patients who undergo subtotal or total thyroidectomy require lifelong thyroxine.

In our series, several complications were seen after thyroid surgery for both benign and malignant thyroid diseases. Reoperative thyroid surgery is an uncommon operation with increased morbidity. Also, the incidence of hypoparathyroidism and recurrent laryngeal nerve injury was noted to be high after thyroidectomy for cancer. Attention to operative technique and anatomic details such as identification of the recurrent laryngeal nerve and parathyroid glands during the operation leads to lower rates of undesirable morbidity. Tissue-sparing procedures, such as thyroid lobectomies and subtotal thyroidectomies, have decreased in number in our department and have been gradually replaced by total thyroidectomy. Total thyroidectomy carries a slightly higher morbidity rate, but it substantially diminishes the recurrence rate.

References

1. Knudsen N, Perrild H, Christiansen E, et al. Thyroid structure and size and two-year follow-up of solitary cold nodules in an unselected population with borderline iodine deficiency. Eur J Endocrinol 2000;142:224-230.

2. Koutras DA, Alevizaki M, Tsatsoulis A, Vagenakis AG. Greece is iodine sufficient. Lancet 2003;362:405-406.

3. Doufas AG, Mastorakos G, Chatziioannou S, et al. The predominant form of non-toxic goiter in Greece is now autoimmune thyroiditis. Eur J Endocrinol 1999;140:505-511.

4. Chow TL, Chu W, Lim BH, Kwok SP. Outcomes and complications of thyroid surgery: retrospective study. Hong Kong Med J 2001;7:261-265.

5. Harness JK, Fung L, Thompson NW, et al. Total thyroidectomy: complications and technique. World J Surg 1986;10:781-786.

6. Ready AR, Barnes AD. Complications of thyroidectomy. Br J Surg 1994;81:1555-1556.

7. Jatzko GR, Lisborg PH, Muller MG, Wette VM. Recurrent nerve palsy after thyroid operations: principal nerve identification and a literature review. Surgery 1994;115:139-144.

8. Hillermann CL, Tarpey J, Phillips DE. Laryngeal nerve identification during thyroid surgery: feasibility of a novel approach. Can J Anesth 2003;50:189-192.

9. Eisle DW. Complications of Thyroid Surgery. In: Eisle DW. Complications in Head and Neck Surgery. St Louis, Mo, Mosby Press, 1993; pp 423-436.

10. Bourrel C, Uzzav B, Tison P, et al. Transient hypocalcaemia after thyroidectomy. Ann Otol Rhinol Laryngol 1993;102:496-501.

11. Glinoer D, Andry G, Ghantrain G, Samil N. Clinical aspects of early and late hypocalcaemia after thyroid surgery. Eur J Surg Oncol 2000;26:571-577.

12. Pottgen DS, Davis JF. Post-thyroidectomy hypocalcaemia. Lancet 1977;1:1217-1220.

13. Lang BHH, Lo CY. Total thyroidectomy for multinodular goiter in the elderly. Am J Surg 2005;190:418-423.

14. Mishra A, Agarwal A, Agarwal G, et al. Total thyroidectomy for benign thyroid disorders in an endemic region. World J Surg 2001;25:307-310.

15. De Jong SA, Demeter JG, Lawrence AM, Paloyan E. Necessity and safety of completion thyroidectomy for differentiated thyroid carcinoma. Surgery 1992;112:734-739.

16. Mazzaferri EL, Jhiang SM. Long-term impact of initial surgical and medical therapy on papillary and follicular thyroid cancer. Am J Med 1994;97:418-428.

17. Rossi RL, Cady B, Silverman ML, et al. Surgically incurable well-differentiated thyroid cancer: prognostic factors and results of therapy. Arch Surg 1988;123:569-574.

18. DeGroot LJ, Kaplan EL. Second operations for 'completion' of thyroidectomy in treatment of differentiated thyroid cancer. Surgery 1991;110:936-939.

19. Schwartz AE, Clark OH, Ituarte P, et al. Therapeutic controversy: thyroid surgery: the choice. J Clin Endocrinol Metab 1998;83:1097-1105.

20. Reeve TS, Delbridge L, Brady P, et al. Secondary thyroidectomy: a twenty-year experience. World J Surg 1988;12:449-453.

21. Acun Z, Comert M, Cihan A, et al. Near-total thyroidectomy could be the best treatment for thyroid disease in endemic regions. Arch Surg 2004;139:444-447.

22. Seiler CA, Glaser C, Wagner HE. Thyroid gland surgery in an endemic region. World J Surg 1996;20:593-597.

23. Lin JD, Chao TC, Huang MJ, et al. Use of radioactive iodine for thyroid remnant ablation in well-differentiated thyroid carcinoma to replace thyroid reoperation. Am J Clin Oncol 1998;21:77-81.

24. Tun M, Salekan K, Mat Sain AH. Reoperative thyroid surgery in Hospital University Sains Malaysia. Malays J Med Sc 2003;10:86-89.

25. Chao TC, Jeng LB, Lin JD, Chen MF. Reoperative thyroid surgery. World J Surg 1997;21:644-647.

26. Hay ID, Grant CS, Taylor WF, McConahey WM. Ipsilateral lobectomy versus bilateral lobar resection in papillary thyroid carcinoma: a retrospective analysis of surgical outcome using a novel prognostic scoring system. Surgery 1987;102:1088-1095.

27. Younes N, Robinson B, Delbridge L. The aetiology, investigation and management of surgical disorders of the thyroid gland. Aust N Z J Surg 1996;66:481-490.

28. Lo CY, Kwok KF, Yuen PW. A prospective evaluation of recurrent laryngeal nerve paralysis during thyroidectomy. Arch Surg 2000;135:204-207.

29. Wagner HE, Seiler C. Recurrent laryngeal nerve palsy after thyroid gland surgery. Br J Surg 1994;81:226-228.

30. Flynn MB, Lyons KJ, Tarter JW, Ragsdale TL. Local complications after surgical resection for thyroid carcinoma. Am J Surg 1994;168:404-407.

31. Rosato L, Avenia N, Bernante P, et al. Complications of thyroid surgery: analysis of a multicentric study on 14,934 patients operated on in Italy over 5 years. World J Surg 2004;28:271-276.

32. Balanzoni S, Altarini R, Pasi L, et al. Prevention of laryngeal nerve lesions in thyroid surgery. Minerva Chir 1994;49:299-302.

33. Bliss RD, Gauger PG, Delbridge LW. Surgeon's approach to the thyroid gland: surgical anatomy and the importance of technique. World J Surg 2000;24:891-897.

34. Bejgamaschi R, Becouarn G, Ronceray J, et al. Morbidity of thyroid surgery. Am J Surg 1998;176:71-75.

35. Bondarenko VO, Ermdo AS, Magomedo RB. Prophylaxis of laryngeal nerve injuries of thyroid surgery. Khirurgiia (Mosk) 2001;1:63-66.

36. Hemmerling TM, Schmidt J, Bosert C, et al. Intraoperative monitoring of the recurrent laryngeal nerve in 151 consecutive patients undergoing thyroid surgery. Anesh Analg 2001;93:396-399.

37. Randolph GW. Surgical anatomy of the recurrent laryngeal nerve. In: Randolph GW, ed. Surgery of the Thyroid and Parathyroid Glands. Philadelphia, Saunders, 2003, pp 300-342.

38. Thomusch O, Sekulla C, Walls G, et al. Intraoperative neural monitoring in surgery for benign goiter. Am J Surg 2002;183:673-678.

39. Teitelbaum BJ, Wenig BL. Superior laryngeal nerve injury form thyroid surgery. Head Neck 1995;17:36-40.

40. Kaplan EL. Thyroid and parathyroid. In: Schwartz SI, Shires GT, Spenser FC, eds. Principles of Surgery. 6th edition. New York, NY, McGraw-Hill, Inc, 1994, pp 1640-1624.

41. Bentrem DJ, Rademaker A, Angelos P. Evaluation of serum calcium levels in predicting hypoparathyroidism after total/near-total thyroidectomy or parathyroidectomy. Am J Surg 2001;67:249-252.

42. Clark OH. Total thyroidectomy: the treatment of choice for patients with differentiated thyroid cancer. Ann Surg 1982;196:361-370.

43. Schroder DM, Chambors A, France CJ. Operative strategy for thyroid cancer: is total thyroidectomy worth the price? Cancer 1986;15:2320-2328.

44. Tisell LE, Nilsson B, Molne J, et al. Improved survival of patients with papillary thyroid cancer after surgical microdissection. World J Surg 1996;20:854-859.

45. Sasson AR, Pingpank JF Jr, Wetherington RW, et al. Incidental parathyroidectomy during thyroid surgery does not cause transient symptomatic hypocalcaemia. Arch Otolaryngol Head Neck Surg 2001;127:304-308.

46. Pattou F, Combemale F, Fabre S, et al. Hypocalcemia following thyroid surgery: incidence and prediction of outcome. World J Surg 1998;22:718-724.

47. McHenry CR, Speroff T, Wentworth D, et al. Risk factors for postthyroidectomy hypocalcemia. Surgery 1994;116:641-648.

48. Richards ML, Bingener-Casey J, Pierce D, et al. Intraoperative parathyroid hormone assay: an accurate predictor of symptomatic hypocalcemia following thyroidectomy. Arch Surg 2003;138:632-636.

49. Zimmet P, Breidahl HD, Nayler WG. Plasma ionized calcium in hypomagnesemia. BMJ 1968;1:622-623.

50. Mortensen L, Hyldstrup L, Chales P. Effect of vitamin D treatment in hypoparathyroid patients: a study on calcium, phosphate and magnesium homeostasis. Eur J Endocrinol 1997;136:52-60.

Evangelos P. Misiakos, MD, Theodore Liakakos, MD, Anastasios Macheras, MD, Aglaia Zachaki, MD, Nikolaos Kakaviatos, MD, and Gabriel Karatzas, MD, FACS 

From the 3rd Department of Surgery, University of Athens School of Medicine, Attikon University Hospital, Athens, Greece.

Reprints requests to Evangelos P. Misiakos, MD, Lecturer in Surgery, 76 Aigeou Pelagous St, Agia Paraskevi, Athens 15341, Greece. E-mail: [e-mail]

Accepted May 12, 2006.

RELATED ARTICLE: Key Points

* Surgery is the mainstay of treatment for thyroid cancer and nodular goiter unresponsive to medical treatment.

* Total thyroidectomy is the preferred approach for thyroid disease.

Table 1. Comparison of the two phases in terms of patients'
demographics, type of surgery, histological diagnoses and postoperative
complications

                         Phase A          Phase B
Features                 (1995-1999)      (2000-2005)      Total

No. of patients (%)      133              131              264
Gender
  Female                 103 (77.4%)      108 (82.4%)      211 (80%)
  Male                    30 (22.6%)       23 (17.6%)       53 (20%)
Age
  <30                     12 (9%)          17 (13%)         29 (11%)
  >30 and <50             54 (40.6%)       52 (40%)        106 (40.3%)
  >50                     67 (50.4%)       62 (47%)        129 (48.7%)
Type of operation
  Total                   91 (68.4%) (a)  115 (87.8%) (a)  206 (78%)
  Subtotal                28 (21%) (b)     11 (8.4%) (b)    39 (14.7%)
  Lobectomy               14 (10.6%) (c)    5 (3.8%) (c)    19 (7.3%)
Operation
  Primary                125 (94%)        129 (98.4%)      254
  Reoperative              7 (6%)           3 (1.6%)        10
Histopathological
  diagnosis
  Nodular goiter          70 (52.6%)       75 (57.4%)      145 (54.9%)
  Hyperplastic/colloid    18 (13.5%)       21 (16%)         39 (14.7%)
    nodule
  Adenoma                 13 (9.9%)         9 (6.8%)        22 (8.3%)
  Thyroid cancer          26 (19.5%)       22 (16.8%)       48 (18.2%)
  Hashimoto thyroiditis    6 (4.5%)         4 (3%)          10 (3.8%)
Complications
  Hematoma               --                 2 (1.5%)         2 (0.75%)
  Hypocalcemia
    Permanent              2 (1.5%)         2 (1.5%)         4 (1.51%)
    Transient              5 (3.8%)         9 (6.7%)        14 (5.3%)
  Vocal cord palsy
    Permanent              1 (0.75%)        2 (1.5%)         3 (1.1%)
    Transient              4 (3%)           5 (3.8%)         9 (3.4%)
  Superior laryngeal       2 (1.5%)       --                 2 (0.75%)
    n. injury
  Wound infection          1 (0.75%)      --                 1 (0.38%)
  Total                   15 (5.6%) (d)    20 (7.5%) (d)    35 (13%)

(a) P < 0.001; (b) P < 0.01; (c) P < 0.001; (d) P = 0.21 (not
significant).

Table 2. Types of surgery performed for 48 patients with thyroid cancer

                                     Phase A      Phase B
Types of surgery                     (1995-1999)  (2000-2005)

Hemithyroidectomy                     8           --
Subtotal thyroidectomy                4           --
Total thyroidectomy                   3           16
Total thyroidectomy plus central     12            5
  compartment lymph node dissection
Total                                27           21