The value of cell block based on fine needle aspiration for lung cancer diagnosis

Computed tomography (CT)-guided percutaneous lung fine needle aspiration (FNA) is a convenient method to obtain samples from pulmonary lesions. FNA has a lower rate of complications than the use of a core needle biopsy, but is more difficult for the diagnosis of cytological samples. We use cell block (CB) and immunocytochemistry (ICC) to improve the accuracy of cytological diagnoses based on CT-guided percutaneous lung FNA.

We collected 526 cytological samples obtained using CT-guided percutaneous lung FNA at Shanghai Pulmonary Hospital from May 2015 to October 2015. CBs were created from these samples, and ICC was performed to help the further histological classification and confirmation of tumor as primary or metastatic. An automated Ventana ALK with clone D5F3 was used to identify ALK fusion protein.

After assessment of the CBs, 32 (6.08%) diagnoses of suspected malignancy were reduced to 10 (1.90%) such diagnoses (P<0.05), and 161 (30.61%) cases of non-small-cell lung carcinoma (NSCLC) were reduced to 33 (6.27%) cases (P<0.05) after their division into specific subtypes. We also diagnosed eight (1.52%, P<0.05) cases of metastatic carcinoma of the lung that were difficult to diagnose by cytological smear alone. Six (3.73%) of 161 NSCLC cases exhibited ALK rearrangement.

CB and ICC are useful for accurate cytological diagnosis using CT-guided percutaneous lung FNA. These approaches are valuable for providing individualized treatment and prognostic evaluations with minor complications.