A. AKGÜN, B. YAZICI, Ö. ERDİM, Ü. YARARBAŞ, H. ÖZKILIÇ

Diferansiye tiroit kanserlerinin takibinde tiroglobulin otoantikorunun önemi

Giriş: Geriye dönük olarak yapılan bu çalışmada, diferansiye tiroid karsinomlu (DTK) hastalarda tiroit ablasyonu öncesi ve sonrasında tiroglobülin otoantikoru (TgAb) değişimi ile tiroglobulin (Tg) ve TgAb düzeylerinin hastalığın sonucuyla ilişkisini değerlendirmek amaçlanmıştır Gereç ve Yöntem: Cerrahi sonrası TgAb seviyesi yüksek olan 27 hasta çalışmaya dahil edildi. Hasta grubu 22 kadın, 5 erkek, yaş aralığı 24-70 yıl olup, 25 papiller, 2 foliküler karsinomdan oluşmaktaydı. Takip süresi 30-88 aydı (ortalama: 45±16 ay). Verilen I-131 miktarı 75-175 mCi arasındaydı (ortalama 104,63±20,84 mCi ). Bulgular: Başarılı ablasyon 25/27 hastada (92,5 %) gerçekleştirildi. Serum Tg ve TgAb seviyeleri ablasyon öncesi ve sonrası karşılaştırıldığında anlamlı olarak azaldı (Tg 1,66±3,70 ng/ml 0,19±0,25 ng/ml, p

The use of TgAb as a marker in differentiated thyroid cancer after ablation theraphy

Introduction: Aim was to evaluate thyroglobulin antibodies (TgAbs) variations before and after ablation and correlate thyroglobulin (Tg) and TgAbs levels to the outcome of disease in differentiated thyroid carcinoma (DTC) Material and Methods: We focused on 27 patients (22 female, 5 male, age range 24-70 years, 25 papillary and 2 follicular carcinoma) who had high levels of TgAbs in the post-surgical period. The follow-up was ranging form 30 to 88 months (mean: 45±16 months). The amount of I-131 administered was 75-175 mCi (mean 104.63±20,84 mCi ) Results: Successful ablation was achieved in 25 of 27 (92.5 %) patients. When pre and post ablation values were compared TgAb and Tg levels regressed significantly (Tg 1.66±3.70 ng/ml 0.19±0.25 ng/ml p<0.05 TgAbs 605.84 ±705.34 IU/ml 0.19±0.25 ng/ml 160.27±166.24 IU/ml p<0.05). After ablation at 6th month TgAbs was normalized in 16/27 (%59) patients and it was elevated in 11/27 (%41). Two of 11 patients with high TgAb underwent a second ablation. In 8/11 patients TgAb levels regressed to the normal range during follow-up. Lung metastasis was detected in 1/11 patients. One patient who had normalized TgAb level following ablation relapsed during follow-up. All 27 patients had Tg levels below 2 ng/ml at postablative 6th month and during follow-up. Conclusion: In DTC patients with elevated TgAb levels, among disease free patients, with successful therapy antibodies decreases significantly at 6th month but it may show a delay to reach normal range. During the follow-up not TgAb level but antibody level changes within time is important.

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