The Predictive Factors of Malignancy in Follicular Lesion of Undeterminated Significance

Öz

Follicular lesion of undetermined significance (FLUS) is defined in the same Group III with the atypia of undetermined significance according to Bethesda Classification but these subgroups have different malignancy rates and tumor characteristics according to the studies. In this study, the aim was to evaluate the preoperative clinicopathologic features of the patients with cytological Bethesda Category III/FLUS thyroid nodules. The 44 patients were divided into two groups based on fine needle aspiration cytology (FNAC) results as benign (pB) and malignant (pM) and compared the preoperative clinical, ultrasonographic findings and FNAC results of two groups. According to the univariate analyses the presence of hiopechogenicity and presence of microcalcification are found to be significantly higher in malignancy (p<0.05 for all). Also, the presence of microcalcifications (p=0.048), and hypoechogenicity (p=0.014) were found to be independent risk factors for malignancy according to logistic regression analysis. In patients with FLUS, it should be remembered that the incidence of malignancy increases and treatment should be considered in the forefront of surgery instead of recurrent FNAC in the presence of hypoechogenicity and microcalcification in ultrasonography, and in patients with nuclear membrane irregularity according to FNAC.

Anahtar Kelimeler

• Malignancy
• Follicular Lesion of Undetermined Significance
• Predictive Factors

Önemi Belirsiz Foliküler Lezyonda Malignitenin Prediktif Faktörleri

Öz

Önemi belirsiz folliküler lezyon (ÖBFL) Bethesda Sınıflamasına göre önemi belirsiz atipi ile aynı üçüncü grupta tanımlanmıştır, ancak bu alt gruplar yapılan çalışmalara göre farklı malignite oranlarına ve tümör özelliklerine sahiptir. Bu çalışmada sitolojik olarak Bethesda Kategori III/ÖBFL tiroid nodüllü hastaların preoperatif klinikopatolojik özelliklerinin değerlendirilmesi amaçlandı. 44 hasta ince iğne aspirasyon sitolojisi (İİAS) sonuçlarına göre benign (pB) ve malign (pM) olarak iki gruba ayrıldı ve iki grubun ameliyat öncesi klinik, ultrasonografik bulguları ve İİAS sonuçları karşılaştırıldı. Tek değişkenli analizlere göre İİAS'ye göre hiopekojenite, mikrokalsifikasyon varlığı ve düzensiz çekirdek varlığı malignitede anlamlı olarak daha yüksek bulundu (tümü için p<0,05). Ayrıca mikrokalsifikasyonlar (p=0,048) ve hipoekojenite (p=0,014) lojistik regresyon analizine göre malignite için bağımsız risk faktörleri olarak bulundu. ÖBFL'li hastalarda ultrasonografide hipoekojenite ve mikrokalsifikasyon varlığında, tekrarlayan İİAS yerine malignite insidansının arttığı ve cerrahinin ön planda düşünülmesi gerektiği unutulmamalıdır.

Anahtar Kelimeler

• Malignite
• Önemi Belirsiz Foliküler Lezyon
• Prediktif Faktörler

Kaynakça

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