The Evaluation of Clinicopathologic Features of Differentiated Thyroid Cancers

Abstract

Objectives: Papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC) constitute most of the differentiated thyroid cancers (DTC). Frequency of follicular variant (FV)PTC, a variant of PTC, has been increasing in recent years. However, the data concerning clinicopathologic, radiologic, and cytologic features of this subtype are limited in the literature. The aim of this study was to compare the clinicopathologic features of patients who were diagnosed and followed-up as FTC and FV-PTC in our institution, and also to investigate if there are differences between two groups in the preoperative radiologic, cytologic characteristics, and histopathologic tumoral features.
Materials and Methods: Totally 177 (144 FV-PTC and 30 FTC) patients were included in this retrospective study. Preoperative thyroid function tests, thyroid antibodies, ultrasonographic and cytologic features of nodules, postoperative histopathologic features of both groups were compared.
Results: FV-PTC group had 23 (16%) male and 121 (84%) female patients, FTC group had 11 (36.70%) male and 19 (63.30%) female patients. FTC group had significantly higher male patients (p=0.009). When preoperative ultrasonographic features were compared, we found that longitudinal diameters and volume of nodules were significantly higher in the FTC group (respectively, p=0.007 and p=0.005). There were no significant differences according to other ultrasonographic features. In comparison to preoperative nodular cytological results according to the Bethesda classification, follicular neoplasia/suspicious for follicular neoplasia (FN/SFN) cytology was found higher in FTC group compared to FV-PTC (15.80% vs 5.30%, p=0.017). In the evaluation of histopathological tumoral features, tumor diameter was detected higher in the FTC group (median tumor diameter; 25 mm vs 14.5 mm, p <0.001). Capsular invasion and vascular invasion were significantly high in the FTC group (respectively, p<0.001 and p<0.001).

Conclusion: FV-PTC is a commonly seen subtype of the PTC. It has been reported that clinical feature of FV-PTC is between classical type PTC and FTC in the literature. Clinicopathologic behaviour of FV-PTC among the other differentiated thyroid cancers can be determined clearly with the further studies. 

Keywords

• Follicular variant of papillary thyroid cancer,follicular thyroid cancer,ultrasound,cytology,tumoral features

Diferansiye Tiroid Kanserlerinin Klinikopatolojik Özelliklerinin Değerlendirilmesi

Öz

Amaç: Diferansiye tiroid kanserinin (DTK) büyük çoğunluğunu papiller tiroid Amaç: Diferansiye tiroid kanserinin (DTK) büyük çoğunluğunu papiller tiroid kanserleri (PTK) ve folliküler tiroid kanserleri (FTK) oluşturmaktadır. PTK varyantlarından olan folliküler varyant- PTK (FV-PTK) sıklığı son yıllarda artmaktadır. Ancak bu alt grup için klinikopatolojik, radyolojik ve sitolojik özelliklere ait literatür bilgisi kısıtlıdır. Bu çalışmada amaç, merkezimizde takip edilen FTK ve FV-PTK tanısı alan hastaların klinikopatolojik özelliklerin karşılaştırılması, preoperatif radyolojik ve sitolojik özellikler ile histopatolojik tümöral özellikler açısından bu iki grup arasında fark olup olmadığının araştırılmasıdır. 

Materyal ve Metot: Bu retrospektif çalışmaya toplam 177 (144 FV-PTK ve 30 FTK) hasta dahil edildi. Her iki hasta grubunun preoperatif tiroid fonksiyon testleri, tiroid antikorları, nodüllerinin ultrasonografik ve sitolojik özellikleri, operasyon sonrası histopatolojik özellikleri karşılaştırıldı.
Bulgular: FV-PTK grubunda 23 (%16) erkek hasta, 121 (%84) kadın hasta var iken, FTK grubunda 11 (%36,70) erkek 19 (%63,30) kadın hasta mevcut olup erkek hastaların sayısı FTK grubunda istatistiksel olarak anlamlı derece fazla idi (p=0,009). Preoperatif ultrasonografik özellikler karşılaştırıldığında FTK grubundaki nodüllerin longitudinal çapı ve volümü FV-PTK grubundan istatistiksel olarak anlamlı derecede daha büyüktü (sırası ile p=0,007 ve p=0,005). Ultrasonografik diğer özelliklerden açısından istatistiksel anlamlı farklılık izlenmedi. Her iki gruptaki nodüllerin preoperatif sitoloji sonuçları Bethesda sınıflamasına göre karşılaştırıldığında folliküler neoplazi/folliküler neoplazi şüphesi (FN/FNŞ) sitoloji sonucu FTK grubunda istatistiksel olarak anlamlı derece daha fazlaydı (%15,80’e karşılık %5,30, p=0,017). Histopatolojideki tümöral özellikle değerlendirildiğinde FTK grubunda tümör çapı, FV-PTK grubundan istatistiksel olarak anlamlı derece daha büyüktü (median tümör çapı 25 mm’e karşılık 14,5 mm, p <0,001). Kapsüler invazyon ve vasküler invazyon görülme oranı FTK grubunda istatistiksel anlamlı olarak daha fazlaydı (p<0,001).

Sonuç: FV-PTK, PTK’ının sık görülen bir alt grubudur. Literatür verilerine göre klinik özelliklerinin klasik tip PTK ile FTK arasında olduğu belirtilmektedir. Diğer DTK’lar içerisinde FV-PTK’nın klinikopatolojik davranışı ileri çalışmalarla daha net bir şekilde tanımlanabilir. 

Anahtar Kelimeler

• Folliküler varyant papiller tiroid kanseri,folliküler tiroid kanseri,ultrasonografi,sitoloji,tümör özellikleri

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