An observational study in Thyroid Diseases, Thyroid Neoplasms and Thyroid Cancer, sponsored by Pirogov Russian National Research Medical University. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-10.
Sponsored by Pirogov Russian National Research Medical University · Observational
THORS is a single-center ambidirectional observational cohort study conducted at Moscow Multidisciplinary Clinical Center "Kommunarka". The study combines retrospective analysis of routinely collected clinical data from patients who underwent thyroid surgery beginning in January 2023 with ongoing prospective accrual of new eligible patients and longitudinal updating of follow-up information. No diagnostic or therapeutic intervention is assigned by the research protocol; all treatment decisions are made as part of routine clinical care. The program evaluates the structure and outcomes of thyroid surgery, postoperative complications, histopathology, repeat and completion procedures, long-term oncologic and functional outcomes, health-care resource use, and the quality and reproducibility of real-world data. Applicable outcomes from the international Core Outcome Set for surgical treatment of differentiated thyroid carcinoma (COS-DTC) are incorporated where they can be reliably measured. The first frozen historical analytical baseline includes 968 unique patients and 1,017 thyroid operations performed from 06 January 2023 through 13 February 2026. The cohort remains open to ongoing enrollment and follow-up
THORS is an umbrella real-world-data research program designed as an open, single-center, ambidirectional observational cohort. The historical component uses secondary data generated during routine care, including operative records, hospitalizations, pathology and immunohistochemistry reports, inpatient and outpatient clinical documentation, repeat admissions, follow-up encounters, and available resource/cost information. After registration, new eligible patients continue to enter the cohort prospectively as part of ordinary clinical practice, and clinically available follow-up information is added longitudinally. The research protocol does not assign the type or extent of thyroid surgery, lymph-node dissection, diagnostic testing, or adjuvant treatment.
The program uses linked patient-, hospitalization-, operation-, pathology-, complication-, and follow-up-level data structures. Raw source values, technically normalized data, automated screening signals, author clinical classification, independent expert classification, and adjudicated values are retained as separate layers whenever applicable. Each substantive substudy has a prespecified scientific question, eligibility criteria, outcome definitions, data freeze, and statistical analysis plan. Missingness, source provenance, discordance between data sources, classification error, and repeated observations within patients are explicitly evaluated.
Clinical objectives include description of surgical practice and pathology; clinically verified postoperative complications; functional outcomes; repeat, completion, and recurrence-related surgery; long-term oncologic outcomes; comparisons of clinically relevant surgical strategies when adequate confounding control is possible; and health-care resource use. Methodological objectives include reproducibility of cohort construction and phenotyping, multi-source detection and expert adjudication of outcomes, data-quality assessment, and the feasibility of measuring the 13 COS-DTC outcomes in routine data.
The historical cohort predates registration. Analyses already completed or initiated on historical data are treated as retrospective baseline analyses and are not represented as prospectively registered. Future substudies are date-stamped through protocol/SAP versions and frozen analytical datasets. The complete prespecified THORS research portfolio is listed in Appendix A of this registration dossier, including methodological, clinical, prognostic, comparative, economic, specialized, long-term, and transferability studies. Prospective questionnaires, research-only biospecimen collection, or additional study-specific procedures require the relevant ethics approval and, when they materially change the registered protocol, an amendment or a separate registration record.
365 studies on the registry are indexed under Thyroid Diseases; 80 are open to participants now.
This study's planned enrollment of 3,000 is above the median of 198 across 158 observational studies indexed under Thyroid Diseases.
Browse Thyroid Diseases studies →Pirogov Russian National Research Medical University is the lead sponsor of 57 studies on the registry; 15 are open to participants now.
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Patients treated surgically for benign or malignant thyroid disease at a single multidisciplinary medical center in Moscow. The population is identified from routine clinical-care data and includes historical patients as well as newly accrued eligible patients. Primary, completion, and repeat thyroid operations are eligible when the relevant data can be linked and the episode meets the specific substudy requirements.
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Exclusion Criteria:
- Procedure predominantly involving the parathyroid glands without a confirmed relationship to thyroid disease.
Patients undergoing surgery involving the thyroid gland for benign or malignant thyroid disease at Moscow Multidisciplinary Clinical Center "Kommunarka". The cohort includes primary, completion, and repeat operations and is updated as new eligible patients and follow-up information become available. Routine-care thyroid surgery. The type and extent of surgery are determined by the treating clinical team according to routine care and are not assigned by the research protocol. Procedures may include hemithyroidectomy, thyroidectomy, completion thyroidectomy, repeat thyroid surgery, central and/or lateral cervical lymph-node dissection, and other clinically indicated thyroid-related procedures. No protocol-assigned comparator. Comparisons between naturally occurring clinical strategies may be performed in prespecified observational substudies with appropriate control of confounding and assessment of positivity.
Clinically Verified 30-Day Postoperative Complication Rate
Proportion of index thyroid operations followed by at least one clinically verified postoperative complication within 30 days, using prespecified event definitions, multiple routine-care sources where available, and expert adjudication. Complication types are reported separately and may include hypocalcemia/hypoparathyroidism, recurrent laryngeal nerve dysfunction, hematoma/bleeding, infection, chyle leak, unplanned reoperation, organ injury, readmission, and other clinically relevant events.
Time frame: Within 30 days after each index thyroid operation
Percentage of Participants With an Unplanned Reoperation Related to Thyroid Surgery Within 30 Days
The number of unique participants who undergo at least one unplanned surgical reoperation related to the index thyroid operation within 30 days will be divided by the number of participants with ascertainable 30-day follow-up and multiplied by 100. Planned completion thyroidectomy is classified separately and is not counted as an unplanned reoperation.
Time frame: Up to 30 days after the index thyroid operation
30-Day Mortality
All-cause death within 30 days of the index thyroid operation, using available in-hospital and post-discharge sources.
Time frame: Within 30 days after index thyroid surgery
Permanent Recurrent Laryngeal Nerve Palsy Due to Surgery
Persistent postoperative vocal-fold dysfunction attributable to surgery at 12 months, with preoperative dysfunction, tumor invasion, and intentional nerve resection considered separately.
Time frame: 12 months after the index operation
Permanent Postoperative Hypoparathyroidism
Persistent postoperative parathyroid dysfunction at 12 months based on prespecified biochemical and treatment criteria.
Time frame: 12 months after the index operation
Percentage of Index Operations in Each Final Histopathologic Diagnosis Category
Among index operations with a valid final pathology report, the number of operations assigned to each prespecified mutually exclusive diagnosis category will be divided by the total number of operations with valid final pathology and multiplied by 100. Categories are differentiated thyroid carcinoma, medullary thyroid carcinoma, other malignant thyroid neoplasm, benign thyroid neoplasm, non-neoplastic thyroid disease, and other or indeterminate pathology.
Time frame: Up to 90 days after the index thyroid operation
Percentage of Participants With Persistent Differentiated Thyroid Carcinoma at 12 Months
Among participants with differentiated thyroid carcinoma and an ascertainable 12-month assessment, the number meeting the prespecified definition of structural or biochemical persistent disease at 12 months will be divided by the total number with an ascertainable assessment and multiplied by 100. A participant is counted once if either the structural or biochemical persistence criterion is met.
Time frame: 12 months after the index thyroid operation
Percentage of Index Operations in Each Mutually Exclusive Thyroid Resection Category
The number of index operations assigned to each prespecified mutually exclusive thyroid resection category will be divided by the total number of eligible index operations and multiplied by 100. Categories are hemithyroidectomy, initial total thyroidectomy, completion thyroidectomy, and other thyroid resection.
Time frame: During the index thyroid operation
Median Available Direct Medical Cost of the Index Hospitalization
Available direct medical cost for the index thyroid-surgery hospitalization will be summarized as the median with interquartile range in Russian rubles among hospitalizations with recorded cost data. Structurally unavailable cost values will be reported as missing and will not be automatically imputed.
Time frame: During the index hospitalization, from admission through discharge, up to 60 days
Percentage of Operations in Each Standardized Pathologic T Category
Among operations with morphologically confirmed primary thyroid carcinoma and an ascertainable pathologic T category, the number of operations in each standardized pT category will be divided by the total number of operations with an ascertainable pT category and multiplied by 100. The pT category is derived from the final pathology report using the prespecified staging rules.
Time frame: Up to 90 days after the index thyroid operation
Percentage of Operations in Each Standardized Pathologic N Category
Among operations with morphologically confirmed primary thyroid carcinoma and an ascertainable pathologic N category, the number of operations in each standardized pN category will be divided by the total number of operations with an ascertainable pN category and multiplied by 100. The pN category is derived from the final pathology report using the prespecified staging rules.
Time frame: Up to 90 days after the index thyroid operation
Percentage of Participants With a New Recurrence of Differentiated Thyroid Carcinoma
Among participants with differentiated thyroid carcinoma who have no evidence of persistent disease after initial treatment, the number who develop a new structural or biochemical recurrence will be divided by the number with evaluable follow-up and multiplied by 100. A participant is counted once if either the structural or biochemical recurrence criterion is met.
Time frame: Up to 5 years after the index thyroid operation
Percentage of Index Operations With Central Neck Lymph Node Dissection
The number of eligible index thyroid operations that include a central neck lymph node dissection will be divided by the total number of eligible index thyroid operations and multiplied by 100. Central and lateral neck dissections are classified separately according to the prespecified operation-classification rules.
Time frame: During the index thyroid operation
Percentage of Index Operations With Lateral Neck Lymph Node Dissection
The number of eligible index thyroid operations that include a lateral neck lymph node dissection will be divided by the total number of eligible index thyroid operations and multiplied by 100. Central and lateral neck dissections are classified separately according to the prespecified operation-classification rules.
Time frame: During the index thyroid operation
Percentage of Participants Undergoing Planned Completion Thyroidectomy Within 12 Months
Among participants who undergo an initial hemithyroidectomy and are eligible for longitudinal trajectory assessment, the number who subsequently undergo a planned completion thyroidectomy within 12 months will be divided by the number with ascertainable 12-month surgical follow-up and multiplied by 100. Planned completion surgery is not classified as an unplanned reoperation.
Time frame: Up to 12 months after the initial hemithyroidectomy
Percentage of Required Real-World Data Elements With Available Values
At each annual data freeze, the number of available values across the prespecified required data elements and eligible operation records will be divided by the total number of expected values for those elements and records and multiplied by 100. Missing, not assessed, not applicable, structurally unavailable, and contradictory values will remain distinguishable in the data-quality report.
Time frame: At each annual data freeze, up to 5 years
Percentage of Operation Records Requiring Manual Clinical Review
At each validation cycle, the number of eligible operation records referred for manual clinical review because of missing, conflicting, ambiguous, or rule-discordant information will be divided by the total number of eligible operation records evaluated in that cycle and multiplied by 100.
Time frame: At each annual validation cycle, up to 5 years
Percentage of the 13 Core Outcome Set for Differentiated Thyroid Carcinoma Domains Classified as Analytically Resolvable
At each annual data freeze, each of the 13 Core Outcome Set for Differentiated Thyroid Carcinoma domains will be classified using a prespecified binary readiness rule. A domain is analytically resolvable only when its definition, eligible population, assessment window, data source, and participant-level outcome status can be determined for the planned analysis. The number of resolvable domains will be divided by 13 and multiplied by 100.
Time frame: At each annual data freeze, up to 5 years
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Plan to share: No — in accordance with national requirements for the security and protection of personal data
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This study is not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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Pirogov Russian National Research Medical University