[Role of preoperative ultrasound-guided inferior parathyroid gland localization and new classification to assist intraoperative search and protection of parathyroid glands].

Objective: To investigate the role and significance of ultrasound-guided inferior parathyroid gland (IPTG) localization in searching and protecting parathyroid glands before thyroid surgery. Methods: A randomized controlled trial study was conducted. A total of 306 patients (433 cases of lateral parathyroidectomy) who underwent primary thyroidectomy and central lymph node dissection in Beijing Tongren Hosipital from March to October 2021 were enrolled. In order to locate IPTG more quickly and effectively, new IPTG classification and the definition of quadrant position were carried out. The patients were divided into the study group (n=228) and the control group (n=205). The study group underwent ultrasound-guided IPTG examination before operation and measured the distance between the IPTG and the lower pole of the thyroid and the midline of the trachea. During the operation, the IPTG was found and protected depending on the localization. The control group did not use any auxiliary preoperative positioning method. The distribution ratio of IPTG and the coincidence rate between intraoperative validation and ultrasound localization were calculated. Results: There were 306 patients enrolled in the final analysis (95 males and 211 females), with a median age of 41 years old (18-70). Type Ⅱ and Ⅲ IPTG accounted for 77.2% (176/228) of the total cases. The total coincidence rate ranged from 72.8% to 79.4% in different IPTG groups. Type Ⅲ and quadrant 2 IPTG had the highest coincidence rate [92.4% (73/79) and 92.9% (79/85), respectively]. The study group had better in situ retention rate [82.0% (187/228) vs 73.2% (150/205), χ2=4.896, P=0.027] and less implantation rate [8.8% (20/228) vs 16.1% (33/205), χ2=5.393, P=0.020] than those of the control group. The in situ retention rate were better in type Ⅲ IPTG group, compared with those of the control group [94.9% (74/78) vs 77.4% (48/62), χ2=7.898, P=0.005]. There was no permanent hypoparathyroidism in two groups and the temporary hypoparathyroidism rate was 32.0% (24/75) and 34.6% (18/52), respectively (χ2=0.095, P=0.758). Conclusion: Ultrasound-guided IPTG localization examination has important implications for searching and protecting IPTG during operation, which can significantly increase in situ retention rate of IPTG and decrease the implantation rate.

[Risk factors for recurrence and survival analysis in locally advanced T4a papillary thyroid carcinoma after R0 resection].

Objective: To investigate the treatment outcomes and risk factors of postoperative recurrence in T4a papillary thyroid carcinoma (PTC). Methods: A total of 185 patients with locally advanced T4a PTC treated in Beijing Tongren Hospital, Capital Medical University from January 2006 to December 2019 were retrospectively analyzed, including 127 females and 58 males, aged between 18 and 80 years, with 74 patients aged over 55 years. According to AJCC thyroid tumor staging, 111 cases were stage I (T4aN0M0 26 cases, T4aN1aM0 35 cases, and T4aN1bM0 50 cases) and 74 cases were stage Ⅲ (T4aN0M0 29 cases, T4aN1aM0 19 cases, and T4aN1bM0 26 cases). Kaplan-Meier method was used to calculate the overall survival and the recurrence-free rate, and univariate and multivariate logistic regression analyses on the clinical data were performed. Results: Recurrent laryngeal nerve invasion was observed in 150 cases, trachea invasion in 61 cases, esophagus invasion in 30 cases, and laryngeal structure invasion in 10 cases. Postoperative follow-up periods were 24-144 months, with an average of 68.29 months. Of the 185 patients, 18 (9.73%) had recurrences or metastases, including 9 cases (4.86%) died of recurrences or metastases. The 5-year and 10-year overall survival rates were respectively 95.21% and 93.10%. The 5-year and 10-year disease-free survival rates were respectively 89.65% and 86.85%. Univariate analysis showed that age of onset, tumor diameter, preoperative recurrent laryngeal nerve palsy, esophageal invasion and cervical lymph node metastasis were the risk factors for postoperative recurrence of T4a PTC(all P<0.05). Multivariate analysis showed that preoperative recurrent laryngeal nerve palsy (OR=3.27, 95%CI: 1.11-9.61, P=0.032) and lateral cervical lymph node metastasis (OR=4.71, 95%CI: 1.19-18.71, P=0.027) were independent risk factors for T4a PTC recurrence. Survival rate of patients with T4a PTC involving only the recurrent laryngeal nerve or the outer tracheal membrane was significantly better than that of patients with tracheal invasion (P<0.05). Conclusions: T4a PTC patients with R0 resection can still achieve good efficacy. Preoperative recurrent laryngeal nerve palsy and lateral cervical lymph node metastasis are independent risk factor for postoperative recurrence in the patients.

[Analysis of the diagnosis and treatment of patients with SMARCB1 (INI-1)-deficient sinonasal carcinoma].

Objective: To summarize the clinical features, treatments and outcomes of patients with SMARCB1(INI-1)-deficient sinonasal carcinoma (SDSC). Methods: Fifteen patients who were diagnosed as SDSC in Beijing Tongren Hospital from October 2016 to June 2021 were retrieved, including nine males and six females, ranged from 25 to 78 years old. For TNM stage, one case was in stage T2, one case was in stage T3, 13 cases were in stage T4; 13 cases were in stage N0, two cases were in stage N2; 14 cases were in stage M0, one case was in stage M1. The most common paranasal sinus affected by tumor was the ethmoid sinus. Five patients were treated by radical surgical resection combined with postoperative adjuvant therapy, four patients treated by neoadjuvant therapy with surgical resection, three patients treated by surgical resection only, one patient treated by neoadjuvant therapy with concurrent chemoradiotherapy, one patient treated by preoperative radiotherapy with surgery, and one patient received palliative chemotherapy. Immunohistochemical analysis was performed in all cases. The Kaplan-Meier method was used to draw the survival curve, and the Log-rank test was used to compare the difference to 20 undifferentiated carcinoma patients with positive INI-1 expression in the same period. Results: Immunohistochemical analysis showed the complete absence of INI-1 expression in the tumor nuclei in all 15 cases. The follow-up information was available with a median follow-up time of 21 months (3-56 months). The 3-year overall survival rate, disease specific survival rate, disease-free survival rate and metastasis-free survival rate were 58.9%, 58.9%, 36.4% and 31.2%, respectively. Disease-free survival in SDSC patients was significantly lower compared with undifferentiated carcinoma patients with positive INI-1 expression (HR=2.87,95%CI:0.92~8.91,P=0.043). Cox regression analysis showed that patients with comprehensive treatment based on surgery had a better prognosis than others (HR=8.61,95%CI:1.38~53.73,P=0.021). Conclusion: SDSC is a highly aggressive malignant tumor with the characteristics of easy recurrence, early metastasis and poor prognosis. INI-1 immunohistochemical analysis is recommended in the pathologically poorly differentiated sinonasal carcinoma. Comprehensive treatment based on radical resection may be the first choice for SDSC patients.