Endoscopic ultrasound-guided fine-needle aspiration cytology in diagnosing intra-abdominal lesions

Abstract

Objectives: Endoscopic ultrasound-guided fine-needle aspiration cytology (EUS-FNAC) is an effective method to acquire tissue from the mucosal, submucosal, and peri-intestinal structure with the pancreas being the most common organ to be targeted. This study is aimed to evaluate the role of EUS-FNAC in pancreatic lesions as well as other gastrointestinal (GI) structures including lymph nodes, upper GI tract, liver, and spleen.

Material and methods: A total of 71 cases were taken in which EUS FNAC was performed over 19 months (2018-July 2019). The details analysis of the cytological features was performed in all these cases along with the clinical outcome. The diagnostic efficacy of the EUS-FNAC was evaluated in these cases.

Results: Out of 71 cases, 36 (50.7%) were male. The most common site being the pancreas 45 (60%) followed by intra-abdominal lymph nodes in 13(17.3%) cases and stomach 7 (9.3%). The neoplastic aspirate was noted in 38 (50.7%) cases. Among malignant lesion, adenocarcinoma was the most common; however, uncommon malignancies such as metastatic malignant melanoma and acinar cell carcinoma were also noted. Malignant lesion in pancreas includes adenocarcinoma (n = 11, 24.4%) followed by neuroendocrine tumor (n = 7, 15.6%). Tuberculosis was one of the common benign lesions to be reported.

Conclusion: EUS-FNAC is an effective tool in the diagnosis of GI lesion particularly in the pancreas where it can avoid unnecessary surgical intervention in advanced malignancies. It can effectively obtain samples for molecular markers for pancreatic cancers. Nonetheless, diagnosing tuberculosis in inaccessible lymph nodes with its help is a lifesaving approach especially in developing countries.

Keywords: Cytology; Endoscopic ultrasound-guided fine-needle aspiration cytology; Fine-needle aspiration cytology; Ultrasonography.

Figure 1:

Echotip ultra 22 needle used for performing endoscopic ultrasound-guided fine-needle aspiration and its various components.

Figure 2:

(a) Periportal lymph node as seen in endoscopic ultrasonography, (b) Endoscopic ultrasound (EUS) elastography showing predominantly green color suggestive of soft lesion, and (c) EUS fine-needle aspiration being performed.

Figure 3:

(a) Fine-needle aspiration (FNA) smear shows cellular smear with clusters and singly scattered tumor cells (×120 May Grunwald Giemsa Stain), (b) Higher magnification to appreciate the cellular morphology with salt and pepper chromatin morphologically consistent with neuroendocrine tumor (×240 May Grunwald Giemsa Stain). (c) FNA smears from head of pancreas lesion show compact 3D clusters and scattered population of tumor cells (×120 May Grunwald Giemsa Stain), (d) Higher magnification shows moderate nuclear pleomorphism with irregular nuclei, coarse chromatin, and inconspicuous nucleoli, morphologically consistent with adenocarcinoma. (×420 May Grunwald Giemsa Stain).

Figure 4:

(a) Fine-needle aspiration smear shows branching papillary fragments with central thin delicate capillaries (×220 May Grunwald Giemsa Stain), (b) Higher magnification shows relatively uniform oval to round eccentrically placed nuclei, few showing characteristic nuclear grooves morphologically consistent with solid pseudopaillary neoplasm. (×420 Hematoxylin and Eosin), (c) Discrete cells with moderate to abundant cytoplasm (×220) May Grunwald Giemsa Stain), (d) Occasional foamy macrophages present. (×420 May Grunwald Giemsa Stain).

Figure 5:

(a) Non-Hodgkins lymphoma in peripancreatic lymph node shows discrete population of atypical lymphoid cells (×220 May Grunwald Giemsa Stain), (b) Oil immersion view of atypical lymphoid cells with prominent nucleoli and vacuolated cytoplasm (×1200 May Grunwald Giemsa Stain), (c) Necrotic aspirate from tubercular pre-aortic lymph node (×220 May Grunwald Giemsa Stain), (b) Acid fast bacilli highlighted on Ziehl Neelsen stain (×1200) (d).