Incidence of Persistence and Recurrence of Differentiated Thyroid Cancer in Post-surgical Cases From a Tertiary Care Hospital in Dubai, United Arab Emirates

TL;DR

This study finds that most thyroid cancer cases labeled as 'recurrent' after surgery are actually persistent disease, suggesting possible treatment gaps.

Contribution

The study clarifies the distinction between persistent and recurrent differentiated thyroid cancer post-surgery in a UAE hospital setting.

Findings

Most re-operations were for persistent disease, not true recurrence.

Only two out of 71 cases met the criteria for recurrence.

Persistent disease was more common in the first year after initial surgery.

Abstract

Background

Despite the excellent prognosis of differentiated thyroid carcinoma, recurrence remains a major concern. However, the persistence of thyroid cancer post-thyroidectomy is not uncommon. We aimed to characterise patients who underwent re-operative surgery for differentiated thyroid carcinoma and analyse the percentage of re-operations that truly were for "recurrent" disease versus the management of persistent disease.

Methods

We conducted a retrospective review of the hospital database, analysing patients who visited the nuclear medicine department at Mediclinic City Hospital, a tertiary care hospital in Dubai, United Arab Emirates, between 2015 and 2022. The study included patients with differentiated thyroid carcinoma who underwent re-operations after total thyroidectomy. Recurrence was defined as the development of disease after a patient had undetectable thyroglobulin and negative radiological scans within one year of the first surgery. Cases were categorised as "recurrent", "persistent", or "unable to classify" in the event of missing data.

Results

Out of 836 patients diagnosed with differentiated thyroid carcinoma who visited the nuclear medicine department, 71 underwent re-operations. The mean age of these patients was 44.4 years (CI 41.7-47.0), of whom 78.9% were females. Almost half (46.5%) underwent re-operations within the first year, and 98.6% were diagnosed with papillary thyroid carcinoma. We were able to classify 63.4% of cases (n=45) as persistent disease, while 24 cases were categorised as "unable to classify". Only two cases met the criteria for recurrent disease.

Conclusion

The majority of cases previously classified as "recurrent" in differentiated thyroid carcinoma were found to be a persistent disease, possibly indicating inadequate therapy. Further research may be required to explore the reasons behind this eye-opening rate of disease persistence. This highlights an area for improvement in the management and future outcomes of differentiated thyroid carcinoma patients.

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