Guided fine needle aspiration cytology of retroperitoneal masses - Our experience

Abstract

Background: Early pathological classification of retroperitoneal masses is important for pin-point diagnosis and timely management.

Aims: This study was done to evaluate the usefulness and drawbacks of guided fine needle aspiration cytology (FNAC) of retroperitoneal masses covering a period of two years with an intention to distinguish between neoplastic and non-neoplastic lesions and to correlate with histologic findings.

Materials and methods: FNAC was done under radiological guidance in all cases using long needle fitted with disposable syringe. Appropriate staining was done and cytology was correlated with histology which was taken as the gold standard for comparison.

Results: Fifty-one patients who presented with retroperitoneal masses were studied. Forty-four lesions were malignant cytologically and 7 were inflammatory (tuberculous). According to radiological and cytologic findings, we classified our cases into four groups: renal tumors, retroperitoneal lymphadenopathy, germ cell tumors, soft tissue tumors. Except for cases of non-Hodgkin lymphoma (NHL) and metastatic lesions, we had sensitivity and specificity of 100%. In NHL the sensitivity and specificity were both 50%. In cases of metastatic adenocarcinoma, the sensitivity and specificity were 84.6% and 81.8%, respectively.

Conclusions: Ignoring the pitfalls, guided FNAC is still an inexpensive and reliable method of early diagnosis of retroperitoneal lesions.

Keywords: Computerized tomography guided; fine needle aspiration cytology; retroperitoneal masses; ultrasound.

Figure 1

(a) Wilms’ tumor- biphasic tumor, cohesive tubular structure and undifferentiated mesenchymal cells (H and E, ×400); b) Renal cell carcinoma - poorly cohesive cells with abundant vacuolated cytoplasm and prominent nucleoli (MGG, ×400)

Figure 2

(a) Seminoma - dispersed cells against a tigroid background, smudged nuclei and small lymphocytes (H and E, ×400); (b) Yolk sac tumor-vaguely glandular clusters of malignant cells with cytoplasm (H and E, ×400)

Figure 3

(a) Paraganglioma-loosely clustered cells with speckled chromatin and resembling follicular arrangement like in thyroid epithelium (MGG, ×400); (b) Extra-skeletal chondrosarcoma cells with moderately enlarged and irregular nuclei, bi-nucleate forms against a background of pale chondroid material (H and E, ×400)