Thymectomy, Thyroid Cancer
Conditions
Keywords
thyroid cancer, isthmus, surgery
Brief summary
Prospective randomized open phase III non-inferiority trial in cT1bN0N1aM0 isthmus tumors of the thyroid comparing: extended Isthmusectomy (Isthmusectomy + Central Neck Dissection)(experimental group) versus total thyroidectomy + Central Neck Dissection (reference group).
Detailed description
The thyroid isthmus is a narrow structure connecting the two lobes of the thyroid. Papillary carcinoma arising from this site accounts for only 1-9% of all thyroid cancers. However, due to its unique anatomical location, it is more prone to extranodal extension and bilateral lymph node metastasis, exhibiting more aggressive biological behavior. The optimal extent of surgery remains controversial: total thyroidectomy facilitates postoperative radioactive iodine therapy and monitoring but results in permanent dependence on thyroid hormone replacement and increases the risk of complications such as hypocalcemia, adversely affecting patients' quality of life. In contrast, conservative approaches like extended isthmusectomy can preserve partial thyroid function, reduce complications, and maintain a better quality of life, making them particularly suitable for low-risk patients with small tumors and no metastasis. Existing retrospective studies indicate no significant difference in recurrence rates between the two surgical approaches, though the evidence remains limited. Therefore, this study aims to conduct a prospective, multicenter, open-label, parallel-controlled, randomized trial to directly compare total thyroidectomy and extended isthmusectomy in terms of postoperative recurrence rates, quality of life, and complications, thereby providing high-quality evidence for surgical decision-making.
Interventions
PROCEDURETotal thyroidectomy
Total Thyroidectomy with bilateral central compartment (level VI) neck dissection - surgical removal of entire thyroid gland and perform bilateral Level VI neck dissection. This is the standard treatment recommended by the Chinese Guidelines for the Diagnosis and Management of Thyroid Nodules and Differentiated Thyroid Cancer (2nd Edition). The participating surgeons all routinely perform complete central neck dissections. They were selected for this study due to their standardized technique, which ensures a consistent surgical approach.
PROCEDUREExtended isthmusectomy
Extended isthmusectomy with bilateral central compartment (level VI) neck dissection : Completely resect the isthmus and portions of the bilateral thyroid gland adjacent to the isthmus, ensuring an R0 resection margin for the tumor, while preserving at least more than half of the bilateral thyroid lobes.
Sponsors
Second Affiliated Hospital, School of Medicine, Zhejiang University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
\- Age 18 years or older. Diagnosis of low-risk differentiated thyroid cancer (papillary, follicular, or Hürthle cell carcinoma). Unifocal tumor located in the thyroid isthmus, cT1b No evidence of extrathyroidal extension, assessed by preoperative ultrasound.
Exclusion criteria
\- Aggressive pathological subtypes (e.g., tall cell, clear cell, columnar cell, or diffuse sclerosing variants of papillary thyroid carcinoma, as well as poorly differentiated types). cN1b. M1 Combined with other suspicious thyroid nodules within the lobes.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Rate of 3-year recurrence | maximum of 3 years after the surgery | defined as thyroid cancer recurrence, metastatic disease from thyroid cancer (whichever occurs first) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Anatomical location of tumor recurrence | maximum of 3 years after the surgery | — |
| Risk of surgical site recurrence | maximum of 3 years after the surgery | recurrence occured in the thyroid bed |
| Health Related Quality of Life | Baseline (post-randomisation/pre-surgery), 4 weeks and 3, 6,12 months after the surgery | Measured using FoP-Q-SF: Scales range from 12-60 with higher scores indicating greater fear of disease progression Measured using THYCA-Qol questionnaires: including 7 symptom dimensions and 6 single items. All items are rated on a 4-point scale (none, a little, quite a bit, very much), scored from 1 to 4. Higher scores on individual items indicate lower quality of life. |
| Number of participants with Hormone Replacement Therapy | 2-4 weeks and 3, 6, 12, 24, 36 months after the surgery | patients who require thyroxin intake |
| Rate of surgical complications | perioperatively, 2-4 weeks, 6 months after the surgery | including transient/permanent hypoparathyroidism, transient/permanent recurrent laryngeal nerve injury, postoperative infection, and postoperative lymphatic fistula. |
Countries
China
Contacts
Primary ContactJingying Zhang, MD
Outcome results
None listed