Incidence and Histopathological Features of Intrathyroidal Parathyroid Excision: A High-Volume Single-Center Retrospective Study

Öz

Background: Intrathyroidal parathyroid glands represent a rare anatomical variant and are recognized as a potential risk factor for incidental parathyroidectomy during thyroid surgery. Their intraoperative identification is challenging due to their atypical localization. Methods: A retrospective analysis was performed on 4,231 thyroid surgeries conducted at a single center between January 2015 and December 2025. Patients with histopathologically confirmed intrathyroidal parathyroid tissue were included. Demographic data, type of surgery, histopathological findings, and pre- and postoperative serum calcium and PTH levels were evaluated. Postoperative hypocalcemia resolving within six months was defined as transient, whereas persistent hypocalcemia beyond six months was considered permanent. Results: Intrathyroidal parathyroid tissue was incidentally excised in 19 patients, corresponding to an incidence of 0.45%. All affected patients were female, with a mean age of 28.6 ± 11.4 years. Histopathological examination demonstrated that the majority of excised parathyroid glands were structurally normal. Transient hypocalcemia occurred in three patients (15.8%) and resolved within six months. No cases of permanent hypocalcemia were observed. No statistically significant changes were detected in postoperative calcium or PTH levels. Conclusion: Intrathyroidal parathyroid glands are an uncommon anatomical variant that may be incidentally excised during thyroid surgery. In this series, their removal was not associated with permanent hypocalcemia. These findings highlight the importance of anatomical variability in the evaluation of incidental parathyroidectomy and postoperative biochemical outcomes.

Anahtar Kelimeler

• Intrathyroidal parathyroid
• incidental parathyroidectomy
• thyroidectomy
• hypocalcemia
• parathyroid preservation

Destekleyen Kurum

NONE

Proje Numarası

NONE

Etik Beyan

The Non-interventional Clinical Research Ethics Committee of Van Yuzuncuyıl University approved this work ethically (confirmation no: 2025/10-46 date: 17/10/2025)

Teşekkür

none

İntratiroidal Paratiroid Eksizyonunun İnsidansı ve Histopatolojik Özellikleri: Yüksek Hacimli Tek Merkezli Retrospektif Bir Çalışma

Öz

Amaç: İntratiroidal paratiroid bezleri nadir görülen bir anatomik varyanttır ve tiroid cerrahisi sırasında insidental paratiroidektomi için potansiyel bir risk faktörü olarak kabul edilmektedir. Atipik lokalizasyonları nedeniyle intraoperatif olarak tanınmaları güçtür. Yöntem: Ocak 2015–Aralık 2025 tarihleri arasında tek merkezde gerçekleştirilen 4.231 tiroid cerrahisi retrospektif olarak incelendi. Histopatolojik olarak intratiroidal paratiroid dokusu saptanan hastalar çalışmaya dahil edildi. Demografik veriler, cerrahi tipi, histopatolojik bulgular ile preoperatif ve postoperatif serum kalsiyum ve PTH düzeyleri değerlendirildi. Altı ay içinde düzelen postoperatif hipokalsemi geçici, altı aydan uzun süren hipokalsemi ise kalıcı olarak tanımlandı. Bulgular: İntratiroidal paratiroid dokusu 19 hastada insidental olarak eksize edildi ve bu durum %0,45 insidansa karşılık geldi. Etkilenen hastaların tamamı kadındı ve ortalama yaş 28,6 ± 11,4 yıl idi. Histopatolojik incelemede eksize edilen paratiroid bezlerinin çoğunun yapısal olarak normal olduğu görüldü. Üç hastada (%15,8) geçici hipokalsemi gelişti ve altı ay içinde düzeldi. Kalıcı hipokalsemi saptanmadı. Postoperatif kalsiyum veya PTH düzeylerinde istatistiksel olarak anlamlı bir değişiklik izlenmedi. Sonuç: İntratiroidal paratiroid bezleri, tiroid cerrahisi sırasında insidental olarak eksize edilebilen nadir bir anatomik varyanttır. Bu seride, intratiroidal paratiroid bezlerinin çıkarılması kalıcı hipokalsemi ile ilişkili bulunmamıştır. Bulgular, insidental paratiroidektomi ve postoperatif biyokimyasal sonuçların değerlendirilmesinde anatomik varyasyonların önemini vurgulamaktadır.

Anahtar Kelimeler

• İntratiroidal paratiroid
• insidental paratiroidektomi
• tiroidektomi
• hipokalsemi
• paratiroid korunması.

Destekleyen Kurum

YOK

Proje Numarası

NONE

Etik Beyan

Bu çalışma, Van Yüzüncü Yıl Üniversitesi Girişimsel Olmayan Klinik Araştırmalar Etik Kurulu tarafından etik olarak onaylanmıştır (onay no: 2025/10-46, tarih: 17/10/2025).

Teşekkür

yok

Kaynakça

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