Difficult problems in thyroid surgery

Carcinoma de tiroides: Descripción de 634 pacientes atendidos en el Hospital Universitario San Ignacio, Bogotá, D.C., Colombia

Introducción. La incidencia del carcinoma de tiroides ha aumentado a nivel mundial, probablemente relacionado con el sobre diagnóstico de nódulos tiroideos asintomáticos. La alta sobrevida del carcinoma diferenciado de tiroides ha permitido posibilidades de manejo quirúrgico menos radicales, o inclusive, la vigilancia activa de tumores seleccionados. Existen reportes de características clínico-patológicas del carcinoma de tiroides de nuestro país distintas a las reportadas en la literatura internacional. Métodos. Estudio observacional descriptivo de una cohorte retrospectiva de pacientes con carcinoma de tiroides atendidos en un hospital universitario entre 2015 y 2020. Resultados. Se identificaron 634 pacientes, el 83,4 % de sexo femenino. La tiroidectomía total con vaciamiento central fue el procedimiento más realizado (86,7 %). De 613 carcinomas diferenciados de tiroides, el 94,2 % corresponden al tipo papilar, seguido por el carcinoma de células de Hürtle (1,6 %); el 26,2 % presentaron subtipos histológicos agresivos y el 28,4 % compromiso tumoral bilateral. En los vaciamientos centrales se encontró 58,7 % de enfermedad metastásica; que fue de 49 % en los pacientes con microcarcinomas papilares (19 %). De las 68 lesiones del nervio laríngeo recurrente, 47 % fueron por secciones oncológicas. Discusión. En nuestra serie, la proporción de pacientes con carcinoma papilar de tiroides y de sus variantes histológicas agresivas, así como el compromiso tumoral bilateral es mayor a lo reportado en la literatura científica. Conclusión. El comportamiento biológico del carcinoma de tiroides es variable y puede tener características diferentes entre regiones; el manejo en nuestro medio debería considerar las características propias de nuestra población.

How uncomplicated total thyroidectomy could aggravate the laryngopharyngeal reflux disease?

Swallowing, voice disorders, throat discomfort and subjective neck discomfort are usually reported by patients with a known thyroid nodule and are correlated to nodular thyroid disease itself. Moreover, in endemic goitrous areas, total thyroidectomy (TT) is the most frequently performed surgical procedure. We are used to relate swallowing, voice and throat discomfort to the mechanical effects of nodular goiter or to thyroidectomy itself, but in both these cases the relationship between symptoms and the thyroid mass or its removal is not always clear or easily demonstrated. How can we explain the persistence of local neck symptoms after TT? And how can TT worsen the dysphagic or dysphonic disorders attributed to the goiter's effect over the surrounding structures? During these years, many articles have analyzed the relationship between the thyroid disease and the laryngopharyngeal reflux, finding more and more evidences of their consensuality, leading to important new management considerations and notable medico-legal implications; if the reason of local neck symptoms is not the thyroid disease, we have to study and specially cure the reflux disease, with specific test and drugs. Therefore, the aim of our study, relying on the published literature, was to investigate how, in demonstrated presence of reflux laryngopharyngitis in patients with nodular goiter and local neck symptoms before and after uncomplicated TT, the surgery could influence our anti-reflux mechanism analyzing the anatomical connection as well as the functional coordination; can we play a part in the post-operative persistence of swallowing and voice alterations and throat discomfort?

What would be left behind if subtotal thyroidectomy were preferred instead of total thyroidectomy?

BACKGROUND

The choice between subtotal thyroidectomy (STT) and total thyroidectomy (TT) for multinodular goiter (MNG) remains controversial.

METHODS

Thyroid tissue samples of 34 patients who underwent TT for multinodular disease between October 2005 and June 2007 in Pamukkale University Hospital, Department of General Surgery were evaluated. Thyroid tissues weighing 2 g each from either side were separated from the main specimen to simulate the tissues that would be left behind if a subtotal resection were performed instead of a total resection. Ki-67 staining was performed.

RESULTS

The mean age of subjects was 49.3 +/- 12 years and 25 (73.5%) were females. Papillary microcarcinomas were found in 4 patients, 1 of which was in a residual thyroid specimen (RTS). Micronodule formations were found in 73.5% of specimens simulating residual thyroid. While Ki-67 indexes of residual thyroid tissues were 4.65% in nodules and 1.91% in normal areas (P < .05), they were 5.42% and 2.84%, respectively, for nodular and normal areas in the main specimens (P < .05).

CONCLUSION

Remnant thyroid tissues, following STT, have a high percentage of micronodule formation with a remarkable cellular proliferative activity.

Primary intrathoracic goiter: a rare and potentially serious entity

BACKGROUND

Here we review primary intrathoracic goiter (P-ITG), a rare but potentially serious congenital entity that is distinct from the much more common secondary intrathoracic goiter. The latter is an extension of cervical thyroid that descends within the mediastinum. In contrast, P-ITGs lack a connection with the cervical thyroid and their blood supply comes from intrathoracic vessels.

SUMMARY

P-ITGs can coexist with a normal or goitrous thyroid gland. When they coexist, either or both may be independently affected by neoplastic, infectious, or infiltrative processes. P-ITGs are mainly located in the anterosuperior mediastinum. Location in posterior or middle mediastinum is observed in 15% of cases, making the diagnosis challenging. Although P-ITGs are rare, they are important because they may reach large dimensions with serious consequences. Compression of the trachea is the most common clinical finding, but compression of other mediastinal organs is also observed. Computerized axial tomography (CT) and radionuclide imaging can suggest or make the diagnosis in most cases. The differential diagnosis includes other mediastinal tumors that show high attenuation on unenhanced CT. The treatment of choice is surgical resection of the goiter through a thoracic approach. Thoracic surgery for resection of a small primary mediastinal goiter is considered to be a relatively safe procedure. Long-standing P-ITGs may cause pressure on the trachea, however, resulting in tracheomalacia. This development is serious in its own right and complicates thoracic surgery.

CONCLUSIONS

Resection through a thoracic approach is the appropriate treatment for a P-ITG. Surgical intervention is usually indicated without delay upon the establishment of the diagnosis because these goiters exhibit progressive growth. When P-ITGs are small, this approach should prevent the development of tracheomalacia and other serious complications.

Total thyroidectomy is improved by loupe magnification

With this study, we verified if a microsurgical approach with magnification could improve the outcome of total thyroidectomy. Ninety-seven patients were consecutively randomized into group A (surgery with x 2.5 magnification and microsurgical instruments, n = 47) or group B (surgery with no magnification, n = 50). The mean operative time was 125 +/- 4.0 min in group A, and 150 +/- 4.0 min in group B (P = 0.00012). The recurrent laryngeal nerve was identified in all patients of group A, and in 96.8% of group B. The overall morbidity rate was 4.0% in group A and 25.5% in group B (P = 0.0038). This study indicates that a microsurgical approach with magnification is feasible, reduces surgical time, and improves the outcome in total thyroidectomy.