The Role of Trop2 in Radioactive Iodine-131 Therapy Sensitivity in Papillary Thyroid Carcinoma (ZL2025)

Clinincal data and pathological specimens from patients who had undergone at least one radioactive iodine-131 (^131I) therapy in the Department of Nuclear Medicine at Jiangxi Cancer Hospital over the past 8-10 years were retrospectively collected (approximately 30-50 cases each in the ^131I treatment-responsive group vs. the ^131I treatment-resistant group). Patients in the ^131I treatment-resistant group underwent ^18F-Trop2 PET-CT imaging.

Inclusion criteria:

1. History of total thyroidectomy with postoperative pathology confirming papillary thyroid carcinoma (PTC);
2. At least one course of ^131I internal radiotherapy.

Exclusion criteria:

1. Presence of other severe comorbidities;
2. Incomplete clinical or follow-up data. The clinicopathological characteristics and Trop2 expression levels in tissue samples were compared between the ^131I treatment-responsive group and the ^131I treatment-resistant group.

Within the ^131I treatment-resistant group, comparisons were made between the rapidly progressing subgroup and the stable-disease subgroup under TSH-suppressive therapy in terms of clinicopathological features, tissue Trop2 expression levels, and SUVmax of metastatic lesions on ^18F-Trop2 PET-CT imaging. Factors influencing progression-free survival and overall survival in ^131I-resistant patients were analyzed.

Study Overview

• Status: Active, not recruiting
• Conditions: PTC; Trop2; I-131
• Intervention / Treatment: Radiation: radioiodine-131 therapy

• Study Type: Observational
• Enrollment (Estimated): 60

Contacts and Locations

Study Locations

• China
  • Jiangxi
    • Nanchang, Jiangxi, China, 330000
      • Jiangxi Cancer Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Probability Sample

Study Population

patients who had undergone total thyroidectomy with postoperative pathology confirming papillary thyroid carcinoma and at least one radioactive iodine-131 (^131I) therapy in the Department of Nuclear Medicine at Jiangxi Cancer Hospital over the past 8-10 years were retrospectively collected

Description

Inclusion Criteria:( 1) History of total thyroidectomy with postoperative pathology confirming papillary thyroid carcinoma (PTC); (2) At least one course of ^131I internal radiotherapy. Exclusion Criteria:(1) Presence of other severe comorbidities; (2) Incomplete clinical or follow-up data.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
RAI responder; The ¹³¹I treatment-responsive group was defined as patients who achieved successful radioactive iodine therapy (i.e., lesions disappeared or showed no long-term progression after radioiodine uptake).	Radiation: radioiodine-131 therapy; surgery, tsh inhibition therapy
RAI nonresponder; The ¹³¹I treatment-resistant group was defined as patients meeting any of the following criteria: No radioiodine uptake in metastatic tissues during the first ¹³¹I treatment, with insignificant decrease or an increase in serum Tg levels before and after therapy; Partial lesions exhibit radioiodine uptake while others showed no uptaking; Progressive metastatic disease despite evident radioiodine uptake.	Radiation: radioiodine-131 therapy; surgery, tsh inhibition therapy

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tumor size;	Lesion size was determined using CT imaging. Lymph nodes were assessed based on their shortest diameter, while other target lesions were evaluated based on their longest diameter. Each measurable lesion underwent an average measurement derived from a minimum of three readings, with all measurements conducted by the same individual to minimize measurement discrepancies. Response Evaluation Criteria in Solid Tumors (RECIST 1.1) were used to assess treatment response	6-60 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serological assessment	Including serum thyroglobulin (Tg) and serum anti-thyroglobulin antibody levels (TgAb) in thyrotropin-inhibited states, as well as tumor markers such as CEA	1-60months

Collaborators and Investigators

• Sponsor: Jiangxi Provincial Cancer Hospital
• Collaborators: Lin Zhou; Zhijun Chen; Yu Su; Jingxiu Zhong; Tianzhu Lu
• Investigators: Principal Investigator: lin zhou, Jiangxi Provincial Cancer Hospital

Study record dates

Study Major Dates

• Study Start (Actual): December 18, 2025
• Primary Completion (Estimated): June 10, 2027
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: December 18, 2025
• First Submitted That Met QC Criteria: December 18, 2025
• First Posted (Estimated): January 2, 2026

Study Record Updates

• Last Update Posted (Estimated): January 2, 2026
• Last Update Submitted That Met QC Criteria: December 18, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: Trop2 and PTC; 202211013 (Other Grant/Funding Number: Jiangxi Provincial Health Commission)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: We will share our plan after our results be published

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No