The role of thymus preservation in parathyroid gland function and surgical completeness after bilateral central lymph node dissection for papillary thyroid cancer: A randomized controlled study

Demographic, clinical, and surgical features of patients undergoing thyroidectomy due to thyroid lesions in Southern Iran: A cross-sectional study

Background and Aims

The incidence of thyroid cancer has witnessed a significant global increase and stands as one of the most prevalent cancers in Iran. This surge is primarily attributed to the escalating incidence of papillary thyroid cancer (PTC), with overdiagnosis emerging as an equally noteworthy factor. Consequently, this study aims to ascertain the incidence of thyroid cancer, along with its clinical presentation, demographic characteristics, and surgical features in patients undergoing thyroid surgery.

Methods

This cross-sectional study involved the evaluation of patient files from referral centers in Shiraz spanning the years 2015-2020. Demographic and clinical information pertaining to thyroid cancer was extracted and subsequently analyzed using SPSS software.

Results

A total of 533 documented cases of thyroid cancer undergoing surgery revealed an annual rate of 89 cases in our location. The average age of the patients was 43.9 ± 13.4 years (ranging from 13 to 92), with females constituting 429 (83.5%) of the cases, and 278 (54.1%) being malignant. Conventional PTC emerged as the most prevalent pathology, accounting for 239 (45.0%) of the cases. Patients with thyromegaly exhibited significantly higher incidences of nonmalignant tumors (p = 0.01), while those with malignant tumors were notably younger than those with nonmalignant tumors (p = 0.001).

Conclusion

Our study revealed a progressive rise in the number of patients undergoing thyroidectomy over the years, with PTC constituting the majority of cases. Malignant cases were more frequently observed in younger patients, and in smaller lesion sizes, highlighting the importance of early screening and optimizing detection methods, especially in high-risk populations.

The necessity of resection of suprasternal fossa fat in total endoscopic thyroidectomy via the areola approach

The identification of a lower boundary for the central lymph node (CLN) of the neck in total endoscopic thyroidectomy via the areola approach (ETA) is important for its radical dissection. We found that resection of the suprasternal fossa fat (SFF) was beneficial for exposing the lower boundary and preventing suprasternal swelling after the operation. This retrospective analysis included 470 papillary thyroid carcinoma (PTC) cases, with some treated by unilateral lobectomy, some by central lymph node dissection (CLND) through ETA (n = 193), and the others by conventional open thyroidectomy (COT, n = 277). The main observation indicators included the total number of CLNs, CLND operative time, visualization of the upper pole of the thymus before removing the CLN, and postoperative suprasternal swelling. The SFF retention group and COT group had a similar percentage of women (78.65% vs. 79.42%, P = 0.876) lower than that in the SFF resection group (95.19%, P < 0.001). The percentage of the visualized upper pole of the thymus before CLN removal was notably higher in the SFF resection group than that in the SFF retention group (63.46 vs. 29.21%, P < 0.001) but notably lower than that in the COT group (63.46% vs. 100%, P < 0.001). A total of 43.82% and 23.1% of patients in the SFF retention and COT groups showed suprasternal swelling, respectively. No patient exhibited such swelling in the SFF resection group (23.1% vs. 0, P < 0.001). Resection of SFF in ETA easily identified the lower boundary for CLND and prevented suprasternal fossa swelling.

The effect of thymectomy during central neck dissection in papillary thyroid carcinoma: a case-controlled study

Central lymph-node dissection (CND) as part of total thyroidectomy is recommended in the treatment of papillary thyroid cancer. CND with thymus resection for achieving more oncological clearance is suggested in guidelines, but the benefits of this technique are still unclear due to the risk of parathyroid glands injury and postoperative hypocalcemia. The aim of this study is to evaluate the risk and benefits of thymectomy in CND with total thyroidectomy. We retrospectively reviewed the records of 188 patients with total thyroidectomy and CND. Participants were divided into 110 patients with CND and thymus resection and 78 patients with thymus preservation. Oncological completeness was evaluated by measuring the postoperative thyroglobulin and hypocalcemia as a postoperative complication was measured by blood calcium level. Based on our findings, patients who underwent thymus resection had a higher incidence of hypocalcemia compared to patients with thymus preservation (56.4% vs. 39.2%; P = 0.027), but there was no significant difference in thyroglobulin levels between these two groups. (P = 0.115 and 0.185, respectively) The proportion of involved to total resected lymph nodes in our study was 28%, which did not statistically differ among the thymus groups. Routine thymus resection during the CND and total thyroidectomy is not recommended because of more postoperative hypocalcemia occurrence and minimal oncological benefit in PTC treatment.

Risk Benefit Analysis of Routine Thymectomy for Differentiated Thyroid Cancers: A Systematic Review

Background  Central compartment lymph node dissection (CLND) is a part of the surgical management of differentiated thyroid cancer (DTC). Therapeutic CLND is done to address clinically significant central compartment nodes in patients with DTC, while prophylactic CLND is performed in the presence of high-risk features in the absence of clinically significant neck nodes. Removal of thymus—unilateral or bilateral—during CLND to achieve complete clearance of level VI and VII lymph node stations and address thymic metastasis is debatable.

Objective  The present systematic review was conducted to summarize the evidence, delineating the role of thymectomy during CLND in patients with DTC.

Methods  Electronic databases of PubMed, Embase, and Cochrane were searched from their inception to July 2020 using keywords—thyroid neoplasms or tumors, thyroidectomy, and thymectomy—to identify the articles describing the role of thymectomy during CLND in DTC. A pooled analysis of surgicopathological outcomes was performed using metaprop command in STATA software version 16.

Result  A total of three studies and 347 patients—total thyroidectomy (TT) with bilateral thymectomy in 154, TT with unilateral thymectomy in 166, and TT alone in 27 patients with DTC—were included in the systematic review. The pooled frequency of thymic metastasis was a mere 2% in patients undergoing either unilateral or bilateral thymectomy. The routine addition of thymectomy does not result in better lymph node clearance. Unilateral and bilateral thymectomy were associated with high chances of transient hypocalcemia (12.0% and 56.1%, respectively).

Conclusion  Routine thymectomy is not warranted during CLND, considering minimal oncological benefit and high risk of postoperative hypocalcemia.

Gasless transaxillary endoscopic thyroidectomy for unilateral low-risk thyroid cancer: Li's six-step method

The past decade has witnessed rapid advances in gasless transaxillary endoscopic thyroidectomy (GTET) for thyroid cancer, which has become a reliable procedure with good therapeutic effectiveness, aesthetic benefits, and safety. This procedure has been widely promoted in some Asian countries; however, few studies have described the specific surgical steps for unilateral low-risk thyroid cancer. Based on a review of the literature and our own clinical experience, we introduce in detail the surgical procedure of GTET for the unilateral low-risk thyroid cancer, briefly summarized into Li's 6 steps: surgical position and incision design; creation of surgical cavities; dissection of the superior pole of the thyroid and its vessels, and identification and protection of superior laryngeal nerve; identification and protection of the superior parathyroid gland, and identification of the inferior parathyroid gland; identification and protection of the recurrent laryngeal nerve and the inferior parathyroid gland, and central neck dissection; and processing of the suspensory ligaments of thyroid gland and en bloc resection of the tumor. The six-step approach is simple to learn. The lymph nodes are dissected first, followed by resection of the primary lesion and protect important structures, which meets the principles of radical tumor treatment. It is hoped that the proposed Li's six-step method can promote the standardized, safe, and wide application in treating early thyroid cancer.

A simple, efficient, and safe way of finding recurrent laryngeal nerve beneficial for PTC patients

BACKGROUND

More surgeons have known the importance of parathyroid grand and recurrent laryngeal nerve protection in the surgery, but there is still plenty of scope to improve the surgical techniques. This study aims at investigating whether the improved method of finding recurrent laryngeal nerve (RLN) can protect parathyroid grand and RLN.

METHODS

One hundred fifty-eight patients were enrolled and divided randomly into the test and control group according to different methods of finding RLN in the surgery. In the experimental group the author could quickly find the laryngeal recurrent nerve in the lower part of the neck and separate along the surface of the recurrent laryngeal nerve to the point where the recurrent laryngeal nerve gets into the larynx close to the thyroid gland named lateral approach, while in the control group the author severed the middle and lower thyroid vein and raised the lower thyroid pole to look for the RLN near the trachea by the blunt separation.

RESULTS

The author identified 152 and 159 parathyroid glands in the test and control group, respectively and there were a lower ratio of auto-transplantation and less operative time in the test group compared with that in the control group. The author also found that the parathyroid hormone level (1 day and 2 months) in the test group was higher than that in the control group. There were no differences in metastatic LN and recurrent laryngeal nerve palsy in the 2 groups.

CONCLUSION

The improved method of finding RLN is a simple, efficient and safe way, and easy to implement.