Ultrasonography Guided Fine Needle Aspiration Cytology with Preparation of Cell Blocks in the Diagnosis of Intra- Abdominal Masses.

Background: Ultrasonography guided Fine Needle Aspiration Cytology (FNAC) is currently the most favoured and increasingly used pre-operative diagnostic procedure in various deep seated neoplastic and non-neoplastic mass lesions. Cell blocks prepared from residual fine needle aspiration (FNA) material can aid in better morphologic assessment and contribute to establish a more definitive cytopathologic diagnosis.

Aim: To assess the value of ultrasonography guided FNAC in the diagnosis of intra-abdominal (non-pelvic) masses.

Objectives: To determine the reliability of ultrasonography guided FNAC in distinguishing neoplastic from non-neoplastic intra-abdominal mass lesions. To assess the usefulness of cell block as a complimentary diagnostic material in the morphologic evaluation of the lesions.

Materials And Methods: Aspirate material was collected from 62 patients with clinically and/or radiologically detected abdominal mass under ultrasonographic (USG) guidance. Pelvic masses were excluded from the study. In every case an attempt was made to prepare cell block (CB) from any residual material after preparation of routine smears. The final cytomorphologic diagnosis was correlated with clinical and radiologic findings, histopathologic diagnosis, follow up and response to therapy information.

Results: The diagnostic yield of USG guided FNAC was 96.77%. The cases included 42 malignant (67.74%), two (3.23%) benign, and 16 (25.8%) non-neoplastic lesions. Two (3.23%) smears were unsatisfactory for evaluation. In 45 out of 62 cases (72.58%) CB preparations were available. There was a good agreement between smear diagnosis and that observed on CB section. Additionally CB yielded better diagnostic material in 15.55% of cases and aided in establishing a more precise final cytopathologic diagnosis. Confirmation of diagnosis in the form of biopsy and/or surgically resected specimen and follow up was available in 56 cases. The overall diagnostic accuracy of USG guided FNAC was 96.43% with a sensitivity, specificity, positive predictive value and negative predictive value of 95.35%, 100%, 100% and 86.66% respectively.

Conclusion: USG guided FNA procedure provides a good diagnostic yield for intra-abdominal masses. Also it has high sensitivity and specificity in differentiating benign from malignant lesions. Cell block preparations facilitate better diagnosis of lesions when reviewed along with cytological smears.