The factors that effect the histopathological results of specimen in completion thyroidectomy

Thyroid cancers are the most commonly seen malignancy of endocrine cancers. Thyroidectomy has a significant place in the treatment of thyroid cancers. Histopathologic examination is mandatory for diagnosis of some type of thyroid cancers despite the clinical examination, radiologic assesment, molecular and biochemical tests. Some significant complications may be encountered after thyroidectomy despite improvement in thyroid surgery, innovative surgical tools and skillful surgeons specialized on thyroid surgery. Currently, there is a trend towards hemithyroidectomy which is a more conservative approach than total thyroidectomy in order to decrease these complications. There are still some debate on the which patient should undergo completion thyroidectomy after hemithyroidectomy. In our study, the data of 60 patients who underwent completion thyroidectomy after hemithyroidectomy and 60 patients selected from the group of total thyroidectomy at the same time period(TİİAB: BETHESDA-3,4 or 5) were compared. We found that a total of 1619 patients underwent the thyroid surgery in our clinic between the date of 01.01.2014-01.10.2019. 1191 patients underwent total thyroidectomy, 321 patients had hemithyroidectomy and 60 patients underwent completion thyroidectomy due to the pathologic result of malignancy done after hemithyroidectomy. We detected that 83.5% of patients who underwent hemithyrodectomy in their first surgery due to the suspicous of malignity were prevented from the total thyroidectomy and its complications. The hospitalization days were found longer in total thyroidectomy patients when compared to hemithyroidectomy and it was statistically significantly different. 17.7 % of patients in total thyroidectomy group who had malignancy in pathologic examination were found to have malignancy in the contralateral lobe, too. 23.3 % of patients who underwent completion thyroidectomy after hemithyroidectomy were found to have malignancy. The development of postoperative hypocalcemia was not different according to the patients with benign or malignant pathological result after completion thyroidectomy. We found statistically significantly that performing completion thyroidectomy between 10-90th days after primary surgery resulted in higher rate of complications and longer hospital stay than surgery performed after 90th day. It was observed that pathology type, age, tumor diameter and serum TSH level did not have a significant effect on the presence of malignancy in the opposite lobe in patients who underwent hemithyroidectomy. In this study, we investigated markers that can predict the malignancy in the contralteral lobe with high detection rate in patients with hemithyroidectomy. As a result of our study, although it was not statistically significant, the factors that may effect the malignant histopathologic outcome in completion thyroidectomy material were found as: the coexistence of male gender and thyroid papillary carcinoma(PTC), men over 45 years of age, the coexistence of male gender with additional risk factors in the first pathological result, completion thyroidectomy performed in the left side and tyroglobulin level higher than 30 ng/ml. And also, we detected that the completion thyroidectomy has lower complication rate than total thyroidectomy. We think that the hemithyroidectomy may be preferred to the total thyroidectomy unless there is an exact indication and completion thyroidectomy can be performed safely and with low morbidity after hemithyroidectomy in case of an indication. Keywords: Total thyroidectomy, hemithyroidectomy, completion thyroidectomy, timing of surgery, complication.