Ahmad SS, Akhtar K, Akhtar SS, Nasir A, Khalid M, Mansoor T

The study was undertaken to evaluate the reliability of ultrasound guided fine needle aspiration biopsy

(FNAB) in distinguishing benign and malignant lesions in the retroperitoneum and correlate the diagnosis

by cytology of retroperitoneal masses with the results obtained by histology. The clinicopathological

study was carried out in 50 patients presenting with retroperitoneal masses on ultrasonography. Fine

needle aspiration under ultrasound guidance of these masses was performed by 20-22G needle after

thorough clinical examination. Malignant lesion constituted the maximum number of cases - 31 (62%)

followed by benign and inflammatory lesion - 16 cases (32%). Eleven cases out of 23 renal masses were

Wilm’s tumour, 4 were renal cell carcinoma and there was a single case of angiomyolipoma of kidney. Out

of 20 cases with retroperitoneal lymphadenopathy 12 cases (60%) were inflammatory, mainly tuberculosis

and 8 (40%) had malignancy. Out of the 7 cases of miscellaneous retroperitoneal masses, 3 were

fibrohistiocytic tumour and 2 were myxoid liposarcoma. Ultrasound guided FNAB is an inexpensive, rapid,

safe and accurate procedure for the diagnosis of retroperitoneal masses.