Remote Results of Surgical Treatment of Patients with Multinodular Euthyroid Goiter

The dissertation is dedicated to the study of remote outcomes of surgical treatment of patients with multinodular euthyroid goiter. The research addresses key complications of operative treatment, including postoperative hypothyroidism, goiter recurrence, and the development of autoimmune thyroiditis in the thyroid remnant. The work is based on clinical material from the Ryazan region and proposes an improved management strategy combining organ-preserving resections with mandatory postoperative anti-recurrence therapy and dispensary monitoring.

In recent decades, thyroidopathies have been steadily progressing in the structure of endocrine diseases. According to the most authoritative researchers, a further increase in the number of patients with thyroid diseases is expected in the coming years (Dedov I.I. et al., 2000; Kalinin A.P. et al., 2004; Bauch K., 1998; Miller F.R., Netterville J.L., 1999). At present, the prevalence of nodular and multinodular euthyroid goiter in the structure of thyroid diseases among the population ranges from 30% to 62%, which is associated with goitrous endemicity, ecological unfavorable conditions, and the weakening of the preventive direction in medicine (Romanchenko A.F., 1992; Kalinin L.P. et al., 2004; Brennan M.D., 1991). Correspondingly, the growth in morbidity increases the number of surgical interventions, since the surgical method is the leading one in the treatment of nodular goiter (Balabolkin M.I., 1998; Dedov I.I. et al., 2001; Vetchev P.S. et al., 2000, 2003; Shulutko A.M. et al., 2002).

Despite the successes achieved in recent years in the prevention and treatment of nodular forms of goiter, the results of operative treatment do not always satisfy either surgeons or endocrinologists, which is primarily associated with the development of postoperative hypothyroidism and disease recurrence (Aristarhov V.G., 1998).

Part of researchers recommend performing extensive resections up to complete organ removal in cases of nodules in the thyroid gland (Tsukanov Yu.T. et al., 1997; Zarivchatsky M.F., 2000; Fadeev V.V., 2002; Vanushko V.E., Kuznetsov N.S., 2002). The outcome of extensive thyroid resections is the development of postoperative hypothyroidism, which worsens the patient's quality of life.

Recently, an increasing number of authors have favored organ-preserving interventions for nodular formations in the thyroid gland in the form of lobectomy, the advantage of which over more extensive procedures lies in the preservation of a sufficient amount of functionally active thyroid parenchyma (Vaskov V.M., Masalskaya T.A., 1998; Aliev Z.O. et al., 2000; Malinovsky N.N. et al., 2000; Kononenko S.N. et al., 2000; Aristarhov V.G., 2000; Evmenova T.D., 2001).

One of the main causes of hypothyroidism is autoimmune thyroiditis. The prevalence of nodular goiter against the background of lymphocytic thyroiditis remains poorly studied, although even after resections of small volume, postoperative hypothyroidism is observed in these patients. In some cases, the autoimmune process in thyroid tissue arises several months, and even years, after surgery (in this case, operative trauma is the provoking factor). The resulting hypothyroidism requires the prescription of replacement hormone therapy. The frequency of development of this type of complication remains poorly studied.

Against the background of progressive increase in the number of surgeries for various thyroid diseases, the number of recurrences continues to increase parallel (Slesarepko S.S. et al., 1997; Zarivchatsky M.F. et al., 2000; Shulutko A.M. et al., 2000; Beloborodov V.A. et al., 2006). Most researchers identify the main causes of the development of postoperative recurrent goiter in the insufficient volume of primary surgical intervention (Valdina E.A., 1993; Shulutko A.M. et al., 2000), and (or) poor-quality intraoperative revision of the thyroid gland (Yaitsev S.V. et al., 1994; Goch E.M., 1995; Beloborodov V.A. et al., 2006). The causes of recurrences occurring after technically flawless operations, most authors associate with inadequate replacement hormone therapy after surgery (Sedov V.M., 1999; Zarivchatsky M.F. et al., 2000; Shulutko A.M. et al., 2000).

However, despite the expansion of the volumes of surgical intervention and the widespread use of thyroid hormone therapy, it has not been possible to reduce the frequency of recurrent goiter. Repeat formation of nodules is diagnosed in 4–37.5% of patients previously operated on for non-toxic nodular goiter.

In this regard, in recent years, among the causes of recurrences, there has been an increasing emphasis on the prolonged effect of unfavorable goitrogenic factors.

Unsatisfactory results of surgical treatment of multinodular goiter, namely frequent recurrences after operative interventions for nodular goiter and a high percentage of postoperative hypothyroidism, the poorly studied fact of the development of autoimmune thyroiditis in the thyroid remnant — all this indicates the relevance of the chosen research topic.

Goal of the Research

The goal of the present study is to improve the results of surgical treatment of patients with multinodular euthyroid goiter through the development of a management strategy for patients.

Tasks of the Research

1. To study the dynamics and features of nodular pathology of the thyroid gland in the Ryazan region.

2. To study the remote results of surgical treatment of patients with multinodular non-toxic goiter.

3. To study the frequency of postoperative hypothyroidism in patients with nodular colloid goiter.

4. To demonstrate the rationale for the application of organ-preserving operations in multinodular euthyroid goiter.

5. To study the frequency of development of autoimmune thyroiditis after surgeries on the thyroid gland.

Scientific Novelty

1. It has been demonstrated for the first time that significant qualitative changes in nodular pathology of the thyroid gland have appeared in the region.

2. It has been demonstrated for the first time that multinodular goiter is represented not only by multinodular colloid goiter but also by multiple adenomas and combinations of several thyroid pathologies.

3. A clear distinction between the concepts "recurrence of a nodule" and "recurrence of goiter" has been introduced for the first time.

4. It has been proven for the first time that one of the causes of the development of autoimmune thyroiditis is operative trauma.

Practical Significance of the Work

Based on the study of thyroid gland pathology in the region, substantial changes in its structure that have occurred in recent years have been demonstrated. This has led to a change in the management strategy for patients with nodular goiter. Indications for surgical treatment have been changed for this group of patients.

Based on the study of the state of the thyroid remnant, hormonal function, and the number of recurrences in the remote postoperative period, it has been demonstrated that the combination of organ-preserving thyroid resections with mandatory postoperative anti-recurrence therapy, as well as mandatory dispensary monitoring of patients, allows for the improvement of the effectiveness of surgical treatment of patients with multinodular non-toxic goiter. This is achieved through the preservation or rapid restoration of the function of the resected thyroid gland, the reduction of structural changes in thyroid tissue, and the decrease in the frequency of recurrences.

The necessity of mandatory dispensary monitoring of operated patients for the timely detection and treatment of autoimmune thyroiditis, the risk of whose development in the postoperative period in unchanged thyroid tissue amounts to up to 24.6%, has been demonstrated.

The theoretical provisions and practical recommendations presented in the dissertation have been incorporated into the work of surgical department No. 2 of Ryazan City Clinical Hospital No. 11, lectures for students of the dental and medical-preventive faculties, resident physicians, and clinical ordinators of Ryazan State Medical University.

Main Propositions to be Defended:

- the most common variant of multinodular non-toxic goiter is a combination of several thyroid pathologies.

- in the benign variant of multinodular non-toxic goiter, it is advisable to perform organ-preserving interventions on the thyroid gland.

- when autoimmune thyroiditis is detected in the thyroid remnant, laser therapy is indicated for the prevention of hypothyroidism.

- postoperative therapy with iodine-containing preparations in patients with nodular colloid goiter, thyroid hormones in patients with benign tumors of the thyroid gland, and, if necessary, laser therapy in the thyroid gland area in patients with morphological signs of autoimmune thyroiditis in the tissue surrounding the nodules allow for a significant improvement in the results of surgical treatment of patients with multinodular euthyroid goiter.

Approval of the Work

The main provisions of the dissertation were reported at meetings of the Ryazan Regional Society of Surgeons (2005, 2007), at a meeting of the Association of Endocrinologists of the Ryazan Region (2005), at an interregional scientific-practical conference dedicated to the 60th anniversary of oncological care in the Ryazan Region (September 15, 2006), and at the First Ukrainian-Russian Symposium on Endocrine Surgery with international participation in Kyiv (October 13–14, 2006).

Publications

Twelve scientific works have been published on the topic of the dissertation, seven of them in the central press (two of them in the foreign press).

Volume and Structure of the Dissertation

The work is presented on 131 pages of typed text, illustrated with 18 tables and 8 diagrams. The dissertation consists of an introduction, a literature review (Chapter 1), materials and methods of research (Chapter 2), results of original research (Chapters 3, 4, 5, 6), conclusion, conclusions, practical recommendations, and a list of references consisting of 262 sources, including 147 domestic and 115 foreign sources.