Aspiration cytodiagnosis of small cell malignancies found in fine needle aspirate (FNA) of the liver: an immunocytochemical study

Hepatocyte paraffin-1, CD10, and CD34 immunostaining as a diagnostic aid in cytologic diagnosis of hepatic cancer

Background

Cytomorphological distinction between hepatocellular carcinoma and metastatic tumors to the liver may be difficult, especially when these have poor differentiation. The present study was done to assess the diagnostic utility of hepatocyte paraffin-1 (HepPar-1), CD10, and CD34 in differentiating hepatocellular carcinoma from metastatic carcinoma.

Materials and Methods

Ultrasound-guided fine-needle aspiration was performed on 50 patients with space-occupying lesions of liver suspicious for malignancy on clinical/radiologic findings. The cytological assessment was done on smears stained with May-Grünwald-Giemsa and hematoxylin and eosin. Cell blocks were prepared, and immunostaining for HepPar-1, CD10, and CD34 was done.

Results

In these 50 patients, hepatocellular carcinoma was diagnosed in 7 and metastatic tumors in 43 cases. The sensitivity of smears in diagnosing hepatocellular carcinoma was 100% and the specificity was 95.3%, while the sensitivity and specificity of cell block were 100%. A canalicular pattern of CD10 immunoreactivity had a 100% positive predictive value for diagnosing hepatocellular carcinoma. CD10 had a sensitivity of 57.1% and 41.9% in identification of HCC and metastatic tumors, respectively. For the diagnosis of hepatocellular carcinoma, the sensitivity of CD34 was 85.7% and the specificity of sinusoidal pattern of immunoreactivity was 100%. The sensitivity and specificity of granular cytoplasmic staining pattern of HepPar-1 were 100% in hepatocellular carcinoma.

Conclusions

The staining patterns of HepPar-1, CD10, and CD34 are highly specific in distinguishing hepatocellular carcinoma from metastasis. These three immunomarkers should be included in the immunocytochemical panel for differentiating hepatocellular carcinoma from metastatic carcinoma to the liver.

Fine needle aspiration: past, current practice and recent developments

Fine needle aspiration (FNA) is a diagnostic technique that has become widely used. The procedure may be performed by interventional radiologists, endoscopists, pathologists and cytotechnologists; diagnostic interpretation of FNA samples is performed by pathologists and cytotechnologists. I provide here an introduction to the technique and applications of FNA with a review of current practice parameters and recent developments in the molecular application of FNA.

Immunocytochemical diagnosis of hepatocellular carcinoma and identification of carcinomas of unknown primary metastatic to the liver on fine-needle aspiration cytologies

BACKGROUND

Difficulties with cytologic diagnoses on fine-needle aspiration cytology (FNAC) of the liver can be overcome by the application of immunocytochemical panels applied on smears. The aim of the current study was to analyze the performance of a panel of monoclonal antibodies to differentiate hepatocellular carcinoma (HCC) from metastatic carcinoma (MC) or regenerative nodules, and to identify the to date unknown primary sites of carcinomas that had metastasized to the liver.

METHODS

In a validating cohort study, 108 FNACs coin lesions in the liver were routinely evaluated applying immunocytochemistry as an ancillary method. All patients had confirmatory histologic and/or clinical follow-up. A total of 23 HCCs were analyzed for the distinction from MC or regenerative nodules applying a panel of HepPar1, alpha-fetoprotein, BerEP4, CD31, CD68, and Ki-67. A total of 85 cases of unknown primary tumor metastatic to the liver were used to identify the tumor sites applying a panel of CK5/6, CK7, CK20, CA 125, thyroid transcription factor-1 (TTF-1), and Cdx2.

RESULTS

Typing accuracy to differentiate HCC from MC or regenerative nodules was 100% and 90.3%, respectively, to identify the primary tumor site of MC. In 23 cases, the site of the primary tumor remained clinically unknown.

CONCLUSIONS

The application of immunocytochemical panels on the same slide used for microscopic diagnosis is a useful tool in the routine assessment of FNACs of the liver to discriminate HCCs from MC or regenerative nodules and for the identification of primary sites of MC. Their performance should be confirmed in a larger series of cases.

Fine-needle aspiration biopsy of hepatic lesions: computerized tomographic-guided versus endoscopic ultrasound-guided FNA

BACKGROUND

Computerized tomographic (CT)-guided fine-needle aspiration (FNA) cytology is a well-established tool in the diagnosis of hepatic lesions. Endoscopic ultrasound-guided FNA (EUS-FNA), developed recently and used predominantly in evaluating mediastinal and pancreatic lesions, provides access to a significant portion of the liver and to perihepatic structures not readily accessible by a percutaneous approach.

METHODS

A recent experience (1997-2002) with CT-guided FNA of liver lesions at the University of Alabama Birmingham (UAB) was compared with the first 2.5 years of EUS-FNA experience (2000-2002). Cases were identified using a SNOMED search and all reports and cytologic slides were retrieved for review.

RESULTS

In 6 years, 34 percutaneous CT-FNA liver biopsies were performed at UAB; in approximately 2.5 years, 16 EUS-FNA liver biopsies were done. In both groups the primary clinical indication was suspected metastatic carcinoma (CT, 41% of cases vs. EUS, 56%). The 2 techniques yielded a similar range of benign, atypical, and malignant diagnoses (CT: 26%, 18%, and 56% vs. EUS: 19%, 25%, and 56%). Because of the clinical setting in which EUS-FNA is usually performed, a much narrower range of neoplasms was sampled by EUS-FNA. Benign gastrointestinal epithelial cells were identified in 60% of the EUS-FNA specimens.

CONCLUSIONS

Early experience suggests EUS-FNA is comparable to CT-FNA in terms of diagnostic utility for hepatic lesions. Anatomy limits EUS-FNA to only a fraction of the hepatic parenchyma, but that fraction includes the hilum and left lobe of the liver and the proximal biliary tract. The gallbladder, extrahepatic biliary system, and perihilar lymph nodes are readily accessible. Proximate high-resolution ultrasound imaging and cytopathologist involvement in the EUS-FNA process are further advantages. Awareness of artifacts inherent in EUS-FNA sampling (i.e., gut epithelial cells) can minimize a potential diagnostic pitfall.

Fine needle aspiration biopsy of the liver: Algorithmic approach and current issues in the diagnosis of hepatocellular carcinoma

The role of fine needle aspiration biopsy (FNAB) in the evaluation of focal liver lesions has evolved. Guided FNAB is still useful to procure a tissue diagnosis if clinical, biochemical and radiologic findings are inconclusive. Major diagnostic issues include: (i) Distinction of benign hepatocellular nodular lesions from reactive hepatocytes, (ii) Distinction of well-differentiated hepatocellular carcinoma (WD-HCC) from benign hepatocellular nodular lesions, (iii) Distinction of poorly differentiated HCC from cholangiocarcinoma and metastatic carcinomas, (iv) Determination of histogenesis of malignant tumor, and (v) Determination of primary site of origin of malignant tumor. This review gives a general overview of hepatic FNAB; outlines an algorithmic approach to cytodiagnosis with emphasis on HCC, its variants and their mimics; and addresses current diagnostic issues. Close radiologic surveillance of high-risk cirrhotic patients has resulted in the increasing detection of smaller lesions with many subjected to biopsy for tissue characterization. The need for tissue confirmation in clinically obvious HCC is questioned due to risk of malignant seeding. When a biopsy is indicated, core needle biopsy is favored over FNAB. The inherent difficulty of distinguishing small/early HCC from benign hepatocellular nodular lesions has resulted in indeterminate reports. Changing concepts in the understanding of the biological behavior and morphologic evolution of HCC and its precursors; and the current lack of agreement on the morphologic criteria for distinguishing high-grade dysplastic lesions (with small cell change) from WD-HCC, have profound impact on nomenclature, cytohistologic interpretation and management. Optimization of hepatic FNAB to enhance the yield and accuracy of diagnoses requires close clinicopathologic correlation; combined cytohistologic approach; judicious use of ancillary tests; and skilled healthcare teams.

Small-cell tumors of the liver: A cytological study of 91 cases and a review of the literature

This study was designed to consider the cytomorphological spectrum, differential diagnosis, and the role of ancillary studies in small-cell tumors of the liver. Three independent pathologists reviewed cytological slides from 91 cases of small-cell tumors of the liver. The results were compared with the findings of three recently published studies (Cytopathology 11 (2000) 262-267; Diagn Cytopathol 19 (1998) 29-32; and Acta Cytol 40 (1996) 937-947). The role of immunohistochemistry in reaching timely and specific diagnoses was also examined. The diagnostic categories included 44 cases of metastatic small-cell undifferentiated carcinoma, 15 cases of metastatic neuroendocrine carcinoma, 10 cases of metastatic adenocarcinoma, 7 cases of malignant lymphoma, 4 cases of hepatocellular carcinoma with small-cell features, 2 cases of cholangiocarcinoma, 1 case of poorly differentiated carcinoma, and 8 cases of rare tumors including granulosa cell tumor (2 cases), sarcoma (4 cases), malignant melanoma with small-cell features (1 case), and meningioma with small-cell features (1 case). Metastatic granulosa cell-tumor, metastatic melanoma, and metastatic meningioma should be included in the differential diagnoses of small-cell malignancies found in the liver.