Cytologic aspect of fibrolamellar hepatocellular carcinoma in fine-needle aspirates

Significance of hepatocyte atypia in liver fine needle aspiration

Fine needle aspiration (FNA) of the liver is frequently the diagnostic procedure of choice for sampling hepatic lesions. One of the main diagnostic challenges in the interpretation of liver FNA is distinguishing dysplastic lesions and well-differentiated hepatocellular carcinoma (WD-HCC) from benign processes, as they share significant cytomorphologic overlap. Furthermore, the diagnosis of HCC often requires evaluation of stroma for invasion, which may not be present on cytology and small needle biopsy specimens. A reporting system for liver cytopathology has yet to be instituted. Without standardized and well-defined criteria for hepatocyte atypia, we recommend limiting the use of atypia in evaluation of liver FNA specimens to describe a diagnosis of exclusion, in which all known benign and neoplastic processes have been ruled out. The cytologic findings on the FNA of a liver nodule may be best reported as atypical hepatocytes in the absence of a core needle biopsy or cell block sufficient to render a definitive diagnosis of HCC.

New insights into the pathophysiology and clinical care of rare primary liver cancers

Hepatocholangiocarcinoma, fibrolamellar carcinoma, hepatic haemangioendothelioma and hepatic angiosarcoma represent less than 5% of primary liver cancers. Fibrolamellar carcinoma and hepatic haemangioendothelioma are driven by unique somatic genetic alterations (DNAJB1-PRKCA and CAMTA1-WWTR1 fusions, respectively), while the pathogenesis of hepatocholangiocarcinoma remains more complex, as suggested by its histological diversity. Histology is the gold standard for diagnosis, which remains challenging even in an expert centre because of the low incidences of these liver cancers. Resection, when feasible, is the cornerstone of treatment, together with liver transplantation for hepatic haemangioendothelioma. The role of locoregional therapies and systemic treatments remains poorly studied. In this review, we aim to describe the recent advances in terms of diagnosis and clinical management of these rare primary liver cancers.

Utility of Cytokeratin7 Immunocytochemistry in the Cytopathological Diagnosis of Fibrolamellar Hepatocellular Carcinoma

Objective

To distinguish fibrolamellar hepatocellular carcinoma (FL-HCC) variant from the conventional hepatocellular carcinoma (HCC) by cytology, immunocytochemistry, and morphometry.

Study Design

Retrospective detailed cytomorphological, immunocytochemical, and morphometric analysis was performed in 6 cases of FL-HCC reported on fine needle aspiration. Cell block immunocytochemistry (CB-ICC) for CK7 and CD68 was performed in four cases. Morphometry was carried out with Cell A software. Area of the cell, nucleus and nucleolus was measured in 50 nuclei per case in 6 cases each of FL-HCC and HCC.

Results

The mean age of patients with FL-HCC was 19 years and all had normal serum alpha-fetoprotein levels. Fine needle aspiration smears showed large polygonal cells with abundant cytoplasm, vesicular nucleus and prominent nucleolus, associated with variably cellular fibrous stromal fragments. Intranuclear inclusions, cytoplasmic eosinophilic inclusions, and bile were also noted. FL-HCC showed strong membrano-cytoplasmic CK7 positivity and cytoplasmic granular and canalicular positivity for CD68. In contrast, HCC showed weak focal positivity for CK7 and only canalicular CD68 positivity. Morphometry revealed that FL-HCC cells were 2.19 times the size of HCC.

Conclusion

CK7 immunocytochemistry on cell blocks is useful for confirming and distinguishing it from HCC.

Fibrolamellar hepatocellular carcinoma in ascitic fluid: A case report with cytohistological correlation

The fibrolamellar variant of hepatocellular carcinoma (FL-HCC) is distinguished from other hepatocellular carcinoma's (HCC) by its unique clinical and pathological features. Cytological features of this tumor on fine needle aspiration have been described earlier. We report a rare case of a 17-year-old African American male with metastatic FL-HCC, diagnosed by body fluid cytology. The patient presented with ascites and computed tomography (CT) scan revealed multiple omental masses and liver lesions. The fluid sample was obtained along with the omental biopsy and was found positive for metastatic fibrolamellar hepatocellular carcinoma. The fluid cytology showed atypical polygonal cells with enlarged nuclei, prominent nucleoli, and abundant granular cytoplasm. Cytomorphologic features of FL-HCC presenting in body fluids have been rarely described before. This case enriches the cytopathology literature by providing awareness of this tumor presenting as metastasis in body fluids, especially in young individuals with liver lesions. Presence of a concurrent biopsy specimen provided cytohistological correlation, as it remains the gold standard for the accuracy and reliability of cytological diagnoses. Diagn. Cytopathol. 2016;44:757-760. © 2016 Wiley Periodicals, Inc.

Fibrolamellar hepatocellular carcinoma: current clinical perspectives

Fibrolamellar carcinoma (FLC) is a variant of hepatocellular carcinoma (HCC), which comprises ∼1%–9% of all HCCs. Although FLC is a variant of HCC, it is distinct from HCC in that it most often affects younger patients (10–35 years of age) with no underlying liver disease. FLC often presents with vague abdominal pain, nausea, abdominal fullness, malaise, and weight loss. Surgery is the current mainstay of treatment for FLC and remains the only potentially curative option. While FLCs are considered less responsive to chemotherapy than their classic HCC counterparts, there have been suggestions that multimodality treatments may be effective, especially in advanced cases. Further research is necessary to determine effective systemic therapies as an adjunct to surgery for FLC.

Cytopathologic diagnosis of liver mass lesions

The liver is a common site for metastatic malignancies, particularly from the gastrointestinal tract. It also may be involved by primary neoplasms, both benign and malignant. Cytopathologic examination of mass lesions of the liver with pertinent use of ancillary studies is a useful method of establishing a correct diagnosis for patient management. The authors reviewed the literature for articles pertaining to cytologic characteristics of specific tumor types, utility of immunohistochemical markers and pertinent molecular studies, differential diagnoses and pitfalls.

Cytologic features of fibrolamellar carcinoma with mucin production: a rare variant of combined hepatocellular-cholangiocarcinoma

Fibrolamellar carcinoma (FC) is an uncommon tumor that usually arises in non-cirrhotic livers of adolescents or young adults. It differs clinically from hepatocellular carcinoma in its better prognosis and lack of gender predilection. Cytologically, the tumor is composed of large polygonal cells with abundant cytoplasm, pleomorphic nuclei, and prominent large nucleoli. A variant of FC with mucinous differentiation has been previously described. These tumors have been regarded as combined hepatocellular cholangiocarcinomas. Herein, we report the case of a 44-year-old Asian female with a large liver mass present for approximately two years. Core needle biopsy with imprint cytology demonstrated FC with areas of intracellular mucin. To our knowledge, cytological features of this rare tumor have not been described before.

Fine needle aspiration biopsy of hepatocellular carcinoma and hepatocellular nodular lesions: role, controversies and approach to diagnosis

The role of fine needle aspiration (FNA) biopsy of the liver has evolved. Advances in imaging modalities have obviated the need for tissue confirmation in clinically classic hepatocellular carcinoma (HCC). The risks of needle tract seeding and haematogenous dissemination have been actively debated. Nowadays, cytopathologists are confronted by smaller and smaller nodules, detected due to increased surveillance of high-risk cirrhotic patients. Tissue characterization of small well-differentiated hepatocellular nodular lesions (size less than and equal to 2 cm) is extremely challenging and has therapeutic implications. Major issues in the cytodiagnosis of HCC include: (i) distinguishing benign hepatocellular nodular lesions, namely, large regenerative nodules, dysplastic nodules, focal nodular hyperplasia and hepatocellular adenoma from reactive hepatocytes; (ii) distinguishing well-differentiated HCC from benign hepatocellular nodular lesions; (iii) distinguishing poorly differentiated HCC from intrahepatic cholangiocarcinoma and metastatic carcinomas; (iv) determining the histogenesis of a malignant tumour; and (v) determining the site of origin of a malignant tumour. An overview of the biological evolution and histopathological aspects of dysplastic nodules, small HCCs and 'nodule-in-nodule' lesions is presented in tandem with clinically relevant nomenclature. An algorithmic approach to FNA diagnosis of HCC and hepatocellular nodular lesions is outlined. Optimal results depend on (i) a dedicated radiologist-cytopathologist team; (ii) an on-site cytology service, (iii) a combined cytohistological approach, (iv) immunohistochemistry, and (v) clinicopathological correlation. As we move towards personalized medicine, it is envisaged that hepatic FNA is likely to become a point of care in the management protocol as it takes on the additional role of procurement of tumour and peritumoural tissues for genomic and proteomic profiling to enable targeted molecular therapy.

Fine-needle aspiration biopsy of hepatocellular carcinoma and related hepatocellular nodular lesions in cirrhosis: controversies, challenges, and expectations

The role of hepatic fine-needle aspiration (FNA) biopsy has evolved. Advances in imaging modalities have obviated the need for tissue confirmation in most hepatocellular carcinomas (HCCs). There is risk of needle-tract seeding. Increasingly, small nodules are being detected on ultrasound surveillance of high-risk patients. Diagnostic challenges associated with cirrhosis include distinction of benign hepatocellular nodules, namely, large regenerative nodules and dysplastic nodules, from reactive hepatocytes; and distinction of well-differentiated HCCs from benign hepatocellular nodules. This paper will discuss (i) controversies regarding preoperative/pretransplantation FNA diagnosis of HCC, (ii) update of biological evolution, nomenclature, and histopathologic criteria for diagnosis of precancerous nodules and small HCCs, and (iii) algorithmic approach to FNA diagnosis of hepatocellular nodules. Optimal results depend on dedicated radiologist-cytopathologist team, on-site cytology service; combined cytohistologic approach, immunohistochemistry, and clinicopathologic correlation. Hepatic FNA is likely to be incorporated as a point of care as we move towards personalized medicine.

Diagnosis of metastatic fibrolamellar hepatocellular carcinoma by endoscopic ultrasound-guided fine needle aspiration

The fibrolamellar variant of hepatocellular carcinoma (FL-HCC) is distinguished from other hepatocellular carcinomas (HCC) by its unique clinical and pathologic features. Cytological features for this tumor on fine needle aspiration (FNA) of primary tumors have been described earlier. We present here a unique case of metastatic FL-HCC diagnosed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of mediastinal adenopathy. A 32-year-old woman with a history of oral contraceptive use presented with nausea and severe abdominal pain but no ascites or stigmata of cirrhosis. She had a past history of resection of a liver lesion. Serial computed tomography scans revealed mediastinal lymphadenopathy and the patient was referred for endoscopic ultrasound (EUS). A transesophageal EUS-FNA was performed and tissue was collected for cytological evaluation by an on-site pathologist with no knowledge of prior history. Based on morphology correlated with prior history received later, a final diagnosis of metastatic FL-HCC in the retrocardiac lymph node was rendered on the EUS-FNA samples. There are very few reports in the literature where a diagnosis of FL-HCC is rendered at unusual sites. This case highlights that EUS-FNA is a relatively non-invasive, rapid, accurate and effective modality in obtaining tissue from otherwise hard-to-reach areas. It also suggests that metastasis of FL-HCC can be observed in mediastinal nodes and that diagnosis based on cytological features can be rendered even when the tumor is identified at unusual locations.

Fibrolamellar hepatocellular carcinoma

Fibrolamellar hepatocellular carcinoma (FHLCC) generally occurs in young individuals lacking a background of chronic liver disease and other risk factors for hepatocellular carcinoma. The clinical presentations of FLHCC are generally nonspecific, and the alpha-fetoprotein level is typically within the normal range in most cases. Imaging studies have a major role in clinical diagnosis, but pathology is the gold standard in confirming diagnosis. Pathological characteristics of FLHCC include the presence of tumor cells with a deeply eosinophilic cytoplasm and macronucleoli surrounded by abundant fibrous bands. The most effective treatment for FLHCC is aggressive surgical resection. This comprehensive literature review gives a full account of the clinical, pathological, and molecular features of FLHCC.

Review of the clinicopathologic features of fibrolamellar carcinoma

Since its first description 50 years ago, fibrolamellar carcinomas (FLCs) have been recognized as a unique type of primary liver cancer. FLCs occur principally in children and young adults and are not associated with chronic liver disease. Their etiology is unknown. The tumor is made up of large polygonal cells containing abundant eosinophilic cytoplasm, large vesiculated nuclei, and large nucleoli, with tumor cells that are embedded in lamellar bands of fibrosis. Although rare, the most common variant of FLC shows areas of glandular type differentiation with mucin production. The uniqueness of FLC extends to their molecular findings, as they show no evidence for involvement by many of the major pathways and genes that are dysregulated in typical hepatocellular carcinoma, including alpha-fetoprotein, TP53 mutations, and beta catenin mutations. FLCs are not indolent tumors, but have an overall better prognosis than hepatocellular carcinomas of the usual sort because of the younger age at presentation and lack of cirrhosis. The most important prognostic feature is resectability. Although their morphologic appearance on routine stains is well defined, their etiology is still unknown and much of their molecular biology remains poorly described and awaits future investigation.

Outcome of patients with fibrolamellar hepatocellular carcinoma

BACKGROUND

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare variant of hepatocellular carcinoma, has distinct pathologic features, and typically occurs in young patients without underlying hepatitis or cirrhosis.

METHODS

Forty-one patients with the pathologic diagnosis of FL-HCC evaluated at our institution between 1986 and 2003 were identified from a prospective database.

RESULTS

Median age of all patients was 27 years. None of these patients had underlying hepatitis or cirrhosis, and only 3 (7%) patients had an alpha-fetoprotein level > 200 ng/mL. Twenty-eight patients with primary disease underwent complete gross resection, and 13 patients were unresectable. In patients treated with resection, median tumor size was 9 cm (range, 3-17), 9 (36%) had vascular invasion, and 14 (50%) had lymph node metastases. There were no perioperative deaths. With a median follow-up of 34 months, 5-year overall survival for resected patients was 76%. However, 5-year recurrence-free survival was only 18%, and of the 9 resected patients with more than 5 years of follow-up, 7 had recurrences. Lymph node metastasis was the only significant negative prognostic factor. Seventeen (61%) patients underwent a second operation for recurrent disease. Median survival for unresected patients with FL-HCC was only 12 months, and no patient survived beyond 5 years.

CONCLUSIONS

FL-HCC occurs in a distinctly different population of patients than common HCC, and patients with FL-HCC generally fare better after complete resection. These tumors have a relatively indolent tumor biology, and late recurrences are common. Repeat resections for recurrence should be considered given the lack of other effective treatment options.

Fine-needle aspirates of hepatocellular carcinoma that are misclassified as adenocarcinoma: correlating cytologic features and performance in the College of American Pathologists Nongynecologic Cytology Program

CONTEXT

The cytologic features of hepatocellular carcinoma in fine-needle aspirates are well described. While some cases are easily distinguished from adenocarcinoma, poorly differentiated tumors can be difficult to differentiate. We reviewed the cytologic findings for 9 aspirates from cases of hepatocellular carcinoma that were frequently misclassified as adenocarcinoma and compared them with another 10 cases of hepatocellular carcinoma that were rarely misclassified.

OBJECTIVE

To compare the cytologic features of cases of hepatocellular carcinoma in fine-needle aspirates that were both rarely and frequently misclassified as adenocarcinoma.

DESIGN

We reviewed a total of 762 interpretations from 19 different cases of hepatocellular carcinoma in liver fine-needle aspiration specimens in the College of American Pathologists Nongynecologic Cytology Program and correlated the cytologic features with performance in the program.

RESULTS

Overall, cases that were frequently misclassified as adenocarcinoma were misclassified 39% of the time (range, 18%-70%), while cases that were rarely misclassified were classified as adenocarcinoma 2% of the time (range, 0%-8%). The difference was statistically significant (P < .001). On review, 4 cytologic patterns were found. The most common pattern for cases that were rarely misclassified was prominent trabeculae of cells and endothelial cells wrapping the trabeculae (6/10 cases vs 2/9 cases that were frequently misclassified). The most common pattern among cases that were frequently misclassified was clusters of cells with granular cytoplasm and associated stripped nuclei (5/9 cases vs 2/10 cases that were rarely misclassified). However, the distribution of neither pattern was significantly different (P = .16 for both). One case with large atypical granular cells, as seen in the fibrolamellar variant, was rarely misclassified. The remaining 3 cases (2 frequently misclassified, 1 rarely misclassified) had a nonspecific a pattern of cells with granular cytoplasm without obvious trabeculae or stripped nuclei.

CONCLUSION

Correctly classifying hepatocellular carcinoma by cytology alone remains a significant challenge. While some patterns are more common in cases that performed well and other patterns are more common in cases that performed poorly, there was no significant difference in the distribution of these patterns. These results suggest that people should support their interpretations of aspirations with either immunologic evidence, biopsy evidence, or review by an experienced cytopathologist. Continued educational efforts in this area may be of value.

Fibrolamellar hepatocellular carcinoma: A case report with cytological features in a sixteen-year-old girl

We report a case of a 16-yr-old girl with a liver tumor revealed by thrombophlebitis of the left leg. On physical examination the patient was found to have painless hepatomegaly. Ultrasound and CAT scan showed a large tumor of the left portion of the liver, measuring 14 cm in diameter. Cytological preparations were touch imprints of the biopsy fragments obtained under ultrasound guidance. Cytological examination using May-Grünwald Giemsa stain revealed highly cellular smears containing large tumor cells with a round nucleus, prominent nucleoli, and abundant granular basophilic cytoplasm. Cytological features were those of fibrolamellar hepatocellular carcinoma, confirmed by histological examination of the biopsy sample as well as the surgical specimen obtained after wide excision of the lesion following ineffective neoadjuvant chemotherapy.

Fine-needle aspirates of adenocarcinoma/metastatic carcinoma that resemble hepatocellular carcinoma: correlating cytologic features and performance in the College of American Pathologists Nongynecologic Cytology Program

CONTEXT

The cytologic features of adenocarcinoma/ metastatic carcinoma in liver fine-needle aspirates are well described. We review the cytologic findings from 16 aspirates of adenocarcinoma/metastatic carcinoma that were frequently misclassified as hepatocellular carcinomas and compare them with 17 cases that were rarely misclassified.

OBJECTIVE

To compare the cytologic features of adenocarcinoma/metastatic carcinoma in fine-needle aspiration specimens of the liver that were frequently misclassified as hepatocellular carcinoma with those of aspirates that were rarely misclassified.

DESIGN

We reviewed a total of 1712 interpretations from 33 different cases of adenocarcinoma/metastatic carcinoma tumor in liver fine-needle aspiration specimens in the College of American Pathologists Nongynecologic Cytology Program and correlated the cytologic features with performance in the program.

RESULTS

Overall, cases that were frequently misclassified as hepatocellular carcinoma were misclassified on average 26% of the time (range, 13%-54%), while infrequently misclassified cases were interpreted as hepatocellular carcinoma on average 0.7% of the time (range, 0%-3%). The difference was statistically significant (P < .001). On review, cases that were frequently misclassified most often had moderate amounts of granular cytoplasm (16/16 cases) and round nuclei with even chromatin (13/16 cases). Trabeculae (3/16 cases), bare nuclei (2/16 cases), and endothelial wrapping (1/16 cases) were also occasionally present. In contrast, cases that were rarely misclassified were more likely to have areas with cells showing scant cytoplasm that were crowded and overlapped or molded (13/17 cases) and contained dark hyperchromatic chromatin (13/17 cases) compared to cases that were frequently misclassified (P < .001 and P = .002, respectively). Trabeculae (2/17) and bare nuclei (2/17 cases) were also rarely present.

CONCLUSION

Cases of adenocarcinoma/metastatic carcinoma with moderate amounts of granular cytoplasm and round nuclei with even chromatin are frequently misclassified as hepatocellular carcinoma. Recognition of this problem, attention to cytologic criteria, and frequent use of immunohistochemical studies and core biopsy may help avoid this 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.

Cytology of low-grade endocrine neoplasms involving liver: A series of 24 specimens, including 4 with hepatoid or glandular features

Low-grade endocrine neoplasms (LGENs) involving the liver usually show typical endocrine features. Occasionally these tumors display cytologic characteristics that mimic hepatocellular carcinoma (HCC) or adenocarcinoma (ACA). Twenty-four liver FNABs from 22 patients were reviewed. Twenty specimens showed cytologic characteristics typical of LGENs, including small to medium-sized cells with salt-and-pepper or granular chromatin, moderate to high N/C ratios, and inconspicuous or absent nucleoli. Plasmacytoid cells were observed in 19 cases. Immunocytochemical stains (ICCs) confirmed endocrine differentiation in 9 cases. 4 FNABs were comprised of larger tumor cells that displayed cytologic features that overlapped with HCC or ACA, including transgressing or wrapping endothelium, moderate to abundant cytoplasm, and conspicuous nucleoli. LGENs involving the liver typically demonstrate characteristic cytologic features. Cases comprised of larger cells with abundant cytoplasm, conspicuous nucleoli, and transgressing or wrapping endothelium may pose diagnostic difficulties. ICCs and plasmacytoid morphology are beneficial in classifying the endocrine origin of these tumors.

Diagnosis of hepatocellular carcinoma: fine needle aspiration cytology or needle core biopsy

Needle core biopsy (NCB) has been the standard procedure for histopathologic diagnosis of hepatic lesions for more than 50 years. In recent years fine needle aspiration cytology (FNAC) has emerged as a minimally invasive, relatively inexpensive and a rapid method of pathologic evaluation of primary or metastatic hepatic masses. The specificity and the positive predictive value of FNAC is very high however, the sensitivity of the procedure widely ranges between 67% to 93%. The two major areas of diagnostic difficulties are differentiation of benign and non-neoplastic hepatic nodules from well differentiated HCC and identification of obviously malignant cells as HCC, cholangiocarcinoma, or metastasis. Preparation of cell blocks, immunohistochemical stains and application of other ancillary techniques are often helpful in difficult cases. In presence of characteristic features a diagnosis of HCC can be established on FNAC however, a negative result does not exclude malignancy. The role of pathologic diagnosis in the assessment of large hepatic masses is well established however, its role in the evaluation of small hepatic nodules (<3 cm) detected during surveillance of high risk patients is still evolving. Considering the overall advantages and cost-analysis, FNAC can be suggested as the initial method of choice for evaluation of hepatic masses in most clinical settings. However, the final choice of the diagnostic procedure should be decided on the basis of working clinical diagnosis and the institutional experience.

Radiologically guided percutaneous fine-needle aspiration biopsy of the liver: retrospective study of 119 cases evaluating diagnostic effectiveness and clinical complications

We reviewed 119 percutaneous, radiologically guided fine-needle aspirations (FNA) from 114 patients with liver masses to evaluate diagnostic effectiveness and complications of this procedure. Satisfactory material was obtained in 118 cases (99%), of which 78 were diagnosed as positive (66%), three suspicious (2%), five atypical (4%), and 32 (27%) as negative for malignancy. Compared to surgical biopsy (48 cases) and clinical data, the sensitivity and specificity of FNA for malignancy was 95.1% and 100%, respectively, yielding a positive predictive value of 100% and a negative predictive value of 88.8%. Four cytology cases (3.4%) were false-negatives (FN); all were interpretive errors. Four FN surgical biopsies (8.3%) were sampling errors. Minor complications occurred in three cases (2.5%). We conclude that FNA is safe and effective for determining the malignant potential of liver masses and should be the procedure of choice. Our experience suggests that having a pathologist present in the radiology suite provides optimal patient care.

Hepatocellular carcinoma-fibrolamellar variant: cytopathology of an unusual case

The fibrolamellar variant of hepatocellular carcinoma (FL-HCC) is an uncommon visceral malignancy with a distinctly better prognosis. An accurate initial diagnosis, therefore, is essential for prognostic and therapeutic reasons. This case report describes the cytomorphology of an unusual case of FL-HCC in a 13-yr-old boy who was found to have a hepatic mass with prominent intraluminal growth pattern seen predominantly in the right hepatic duct. A diagnosis of FL-HCC was originally suspected on bile duct brushings obtained during endoscopic retrograde choleangiopancreaticogram (ERCP) and subsequently confirmed on fine-needle aspiration (FNA) and surgical resection of the hepatic tumor. The cytomorphologic profile of FL-HCC is distinctive in the right clinical setting, allowing an accurate preoperative identification of this malignancy on biliary brushing or FNA.

Fine-needle aspiration cytology and differential diagnoses of fibrolamellar hepatocellular carcinoma metastatic to the mediastinum: case report

We report a case of fibrolamellar hepatocellular carcinoma (FL-HCC) that metastasized to the posterior mediastinum. The diagnosis was made on fine-needle aspiration biopsy (FNAB). The cytologic features were characterized by the presence of large, dishesive, polygonal cells with granular cytoplasm and well-defined cell outlines resembling oncocytes. Groups of neoplastic hepatocytes containing bile pigment were also noted. The diagnosis of FL-HCC in a metastatic site can pose diagnostic challenges on FNAB. The cytologic features overlap with a variety of tumors that have oncocytic features and also with melanoma and paraganglioma. Recognition of specific cytologic features of FL-HCC can facilitate accurate diagnosis in a metastatic site. The cytologic findings and differential diagnoses of FL-HCC that metastasized to the posterior mediastinum are discussed.