Accuracy of fine needle aspiration cytology in the pathological typing of non-small cell lung cancer.
BACKGROUND
Histological typing of non-small cell lung cancer (NSCLC) has an increasing clinical relevance due to the emerging differences in medical treatment between squamous and nonsquamous tumors. However, most NSCLCs are diagnosed in an advanced stage, and the diagnosis is often obtained exclusively by cytology either exfoliative or following fine needle aspiration. We investigated the accuracy of fine needle aspiration cytology (FNAC) in NSCLC typing as compared with histology.


METHODS
Over the period 2000-2009, 1182 transbronchial needle aspirate or transthoracic needle aspirate samples were obtained from patients with suspicious thoracic lesions. In 474 patients, a cytological diagnosis of primary NSCLC was obtained, and 186 (39%) of them (108 transbronchial needle aspirates and 78 transthoracic needle aspirates) received a parallel or subsequent histologic diagnosis on endoscopic biopsy (112) or surgery (74).


RESULTS
At cytology, 158 (85%) NSCLC cases were typed (89 adenocarcinoma and 69 squamous cell carcinoma), while 28 (15%) were classified as NSCLC not otherwise specified. At histology, 183 (98%) cases were typed (109 adenocarcinoma, 69 squamous cell carcinoma, 3 adenosquamous carcinoma, and 2 large cell carcinoma), and only 3 (2%) were classified as NSCLC not otherwise specified. Cytological and histological typing was concordant in 137 of 156 (88%) cases (K = 0.755; p < 0.001). The positive predictive value of FNAC in typing NSCLC was 92% for adenocarcinoma and 82% for squamous cell carcinoma.


CONCLUSIONS
FNAC in expert hands is fairly accurate for typing NSCLC and can be regarded as an acceptable procedure for diagnostic and medical treatment planning purposes in most NSCLC cases, especially when more invasive approaches are unfeasible. In poorly differentiated and doubtful cases, the use of ancillary techniques, such as immunocytochemistry, may be required to improve the diagnostic yield.
Medical Oncology Unit, University Hospital of Parma, Parma, Italy.
Rita
R
Nizzoli
Marcello
M
Tiseo
Francesco
F
Gelsomino
Marco
M
Bartolotti
Maria
M
Majori
Lilia
L
Ferrari
Massimo
M
De Filippo
Guido
G
Rindi
Enrico Maria
EM
Silini
Annamaria
A
Guazzi
Andrea
A
Ardizzoni
D000230:Adenocarcinoma / Q000145:classification / Q000473:pathology*; D044963:Biopsy, Fine-Needle; D018196:Carcinoma, Adenosquamous / Q000145:classification / Q000473:pathology*; D018287:Carcinoma, Large Cell / Q000145:classification / Q000473:pathology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000145:classification / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000145:classification / Q000473:pathology*; D003581:Cytodiagnosis; D006801:Humans; D008175:Lung Neoplasms / Q000145:classification / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D012680:Sensitivity and Specificity