Correlation of Computed Tomography Findings with Histopathology in Small Lung Adenocancer

Abstract

Objectives: To analyse the correlation between computed tomography (CT) features and histopathological findings of small lung adenocancers using the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society Classification of Lung Adenocancer. Materials and Methods: A retrospective review of 34 nodules (size ≤2 cm) representing lung adenocancer was performed. Besides their attenuation type (solid, mixed, pure ground glass), tumours were defined as air-containing type if their vanishing ratio was ≥%50 and as solid-density type if the vanishing ratio was <%50. The correlation between CT findings (size, air bronchogram, intranodular lucencies, spiculation, lobulation, notches, pleural retraction and thickening, thickening of bronchovascular bundle) and pathological results was investigated. Tumours representing adenocancer in situ (AIS) and minimally invasive adenocancer (MIA) were investigated in one group as non-/minimally invasive adenocancer (NMIA). Results: Of the 34 nodules 23 (67.7%) were invasive adenocancer, nine (26.4%) were AIS, and two (5.9%) were MIA. Lesions diagnosed as invasive adenocancer were more often of solid-density type (19, 82.6%), and solid (13, 56.5%) or mixed nodules (10, 43.5%) whereas NMIA group lesions were more often of air-containing type (9, %81.8), and pure ground-glass (3, 27.3%) or mixed nodules (7, 63.6%) with a statistically difference between invasive adenocancer and NMIA group (p≤0.05). Furthermore, invasive adenocancer nodules had a larger maximum diameter (15.09±3.32 mm) than NMIA nodules (12.28±3.23 mm) (p=0.031). Thickening of bronchovascular bundle was another CT finding that was significantly more common in invasive adenocancer (p=0.024). The other CT findings showed also a higher frequency in invasive adenocancer compared to NMIA group except for intranodular lucency which was observed in both pathological groups equally. But this difference in frequency was not statistically significant (p>0.05). Conclusion: Invasive adenocancer and NMIA lesions can be differentiated by their CT features. But greater study populations are needed for further confirmation.

Keywords

• Lung Adenocancer
• IASLC/ATS/ERS Classification
• Computed Tomography

Küçük Akciğer Adenokanserlerinin Çok Kesitli Bilgisayarlı Tomografi Bulguları ile Histopatolojik Bulgularının Karşılaştırılması

Abstract

Amaç: Bu çalışmada küçük akciğer adenokanserlerinin bilgisayarlı tomografi (BT) bulguları ile histopatolojik bulguları, Uluslararası Akciğer Kanserini Araştırma Derneği, Amerikan Toraks Derneği ve Avrupa Solunum Derneği’nin sınıflaması esas alınarak karşılaştırılmıştır. Gereç ve Yöntem: Akciğer adenokanser tanısı alan 34 nodül (≤2 cm) retrospektif olarak tarandı. Attenüasyon tiplerinin (solid, mikst, saf buzlu cam) yanı sıra, kaybolma oranları ≥%50 olan tümörler hava-içerikli tip, kaybolma oranları <%50 olan tümörler ise solid-dansite tip olarak kategorize edildi. BT bulguları (boyut, hava bronkogramı, intranodüler lüsensi, spikülasyon, lobülasyon, çentiklenme, plevral çekinti ve kalınlaşma, bronkovasküler demet kalınlaşması) ile patolojik sonuçlar arasındaki korelasyon araştırıldı. Bu amaçla, adenokanser in situ (AİS) ile minimal invazif adenokanser (MİA) non-/minimal invazif adenokanser (NMİA) grubunda ele alındı. Bulgular: Otuz dört nodülün 23’ü (%67,7) invazif adenokanser, dokuzu (%26,4) AİS ve ikisi (%5,9) MİA idi. İnvazif adenokanser tanılı lezyonların çoğu solid-dansite tip (19, %82,6) ve solid (13, %56,5) veya mikst nodül (10, %43,5) iken NMİA grubu lezyonlar daha sık olarak hava içerikli tip (9, %81,8) ve saf buzlu cam dansitesinde (3, %27,3) veya mikst nodül (7, %63,6) şeklinde izlendi. Bu fark istatistiksel olarak anlamlıydı (p≤0,05). Ayrıca invazif adenokanserlerin maksimum çapı (15,09±3,32 mm) NMİA grubu nodüllerin maksimum çapından (12,28±3,23 mm) daha büyüktü (p=0,031). Bu bulgulara ek olarak bronkovasküler demet kalınlaşması istatistiksel olarak anlamlı şekilde invazif adenokanserde daha sık izlendi (p=0,024). İntranodüler lüsensi hariç diğer BT bulguları da invazif adenokanserde daha sık izlenmekle birlikte bu bulgularda izlenen farklar istatistiksel olarak anlamlı değildi (p>0,05). Sonuç: Çalışmamızda BT bulguları ile invazif adenokanserlerin NMİA grubu lezyonlardan ayrılabileceği görülmüştür. Ancak bu sonuçların daha geniş hasta popülasyonunu kapsayan çalışmalar ile teyit edilmesi gerekmektedir.

Keywords

• Akciğer Adenokanseri
• IASLC/ATS/ERS Sınıflaması
• Bilgisayarlı Tomografi

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