Immunocytochemical identification of carcinomas of unknown primary in serous effusions

Decoding the primary tumor origin in carcinomatous serous effusions by immunocytochemistry

INTRODUCTION

Malignant effusions are commonly encountered in day-to-day cytology practice. Determining the primary site of malignancy in carcinomatous effusions is a Herculean task. Cytology coupled with immunocytochemistry is often found helpful in this context.

MATERIALS AND METHODS

This study was undertaken to evaluate diagnostic utility of immunocytochemistry (ICC) on the sections from cell blocks (CBs) to detect the primary site of origin in metastatic carcinomatous effusions. To determine the origin of the primary tumor, TTF1 (lung), PAX-8 (ovary), CDX2 (colo-rectal), GATA3 (breast), and CK19 (pancreaticobiliary) were employed depending on the clinical and radiological findings, and serum tumor markers.

RESULTS

A total of 13,459 serous effusion samples were received for cytological evaluation from January 2017 to December 2021 of which 2708 (20.1%) were carcinomatous effusions. Out of these, 1044 (38.5%), 1611 (59.5%), and 53 (2.0%) were from pleural, peritoneal and pericardial cavities, respectively. Of these, majority were adenocarcinoma. ICC was done in 309 (11.4%) cases. Ovary was the most common primary site in 179 (57.9%) cases, followed by lung (75, 24.3%), pancreaticobiliary (12, 3.9%), colo-rectal (8, 2.6%), breast (6, 1.9%), prostate (2, 0.6%) and kidney (1, 0.3). Lung was the commonest primary site in pleural (67/113, 59.3%) and pericardial (6/8, 75%) effusions. Ovary (168/188, 89.4%) was the most common primary responsible for carcinomatous effusions in the peritoneal cavity. However, in 17 (5.5%) cases, the exact primary site could not be established.

CONCLUSIONS

Judicious and methodical use of ICC on CB helps identify the primary site of the tumor in most carcinomatous effusions. This is of immense help to the treating clinician in directing appropriate therapy.

In pursuit of the primary

Extraovarian primary peritoneal carcinoma (EOPPC) is a rare tumour of the peritoneum that shares many features with serous ovarian carcinoma because of a common embryological origin. We report a case of EOPPC presenting with a malignant pleural effusion.https://bit.ly/3GMuKgL

The cell of cancer origin provides the most reliable roadmap to its diagnosis, prognosis (biology) and therapy

Cancers arise from single transformed cells from virtually every organ of the body, divide in a relatively uncontrolled manner, and metastasize widely. A search for a "magic bullet" to precisely diagnose, characterize, and ultimately treat cancer has largely failed because cancer cells do not differ significantly from their organ-specific cells of origin. Instead of searching for genomic, epigenetic, transcriptional, and translational differences between cancers and their cells of origin, we should paradoxically focus on what cancer cells have in common with their untransformed cells of origin. This redirected search will lead to improved diagnostic and therapeutic strategies where therapeutic index considerations and drug-limiting toxicities can largely be circumvented. We cite three cancer examples that illustrate this paradigm-shifting strategy: pseudomyxoma peritonei (PP), metastasis of unknown origin (cancers of unknown primary) (MUO), and cancers that arise from potentially dispensable organs (CAD). In each of these examples, the cell of cancer origin still provides the most reliable road map to its diagnosis, prognosis (biology), and therapy.

Malignant pleural effusion and cancer of unknown primary site: a review of literature

Malignant pleural effusions (MPE) are most frequently (50-65%) noted from lung and breast cancers. They are commonly unilateral and are reflective of poorer prognosis. Cancer of unknown primary (CUP) account for 4-5% of all invasive cancers. These are metastatic tumors in which the primary is unknown despite an extensive medical evaluation. About 11% of MPE are from CUP. These MPEs present a clinical dilemma to physicians as there is a paucity of literature on their management and no consensus or guideline statement. This paper provides an overview of MPE from CUP in regard to diagnosis, prognosis, and treatment options. A selective search was performed in Medline and PubMed, with the keywords "Malignant pleural effusion" and "Cancer of unknown primary" up to December 2018. A review of literature would suggest that a thoracentesis is the first step in all cases but additional work up such as thoracoscopy & pleural biopsies is frequently warranted. With advances in immunohistochemical staining and biomarker development, MPE with CUP maybe profiled in a similar manner as lung cancer. Similarly, liquid biopsy or identification of circulating tumor cell free DNA may have a role in the work up of CUP in the future. There is some experience in managing these patients with gene directed therapies and immune checkpoint inhibitors, however, with mixed results. Given the poor prognosis associated with MPE from CUP, symptom alleviating measures such as indwelling pleural catheters should be part of the management strategy.

Discerning the Primary Carcinoma in Malignant Peritoneal and Pleural Effusions Using Imaging Mass Spectrometry-A Feasibility Study

PURPOSE

Malignant effusions challenge diagnostic accuracy due to cytomorphologic overlaps between various malignant primaries. Workup of this material to establish a correct diagnosis is time consuming and limited by the sparsity of material. In order to circumvent these drawbacks, the use of MALDI imaging MS (IMS) as a diagnostic platform has been explored.

EXPERIMENTAL DESIGN

Cytology cell blocks from malignant effusions (serous ovarian carcinoma and several non-ovarian carcinomas including gastric adenocarcinoma) containing at least 30% neoplastic cells are selected for generation of cytology microarrays (CMA). CMA sections are transferred to conductive glass slides, subjected to on-tissue tryptic digestion, and matrix application for MALDI-IMS analysis.

RESULTS

Supervised classification analysis identifies serous ovarian carcinomas as the source of malignant effusions with a sensitivity of 85.7% when compared to samples from all other included primary sites. When compared to gastric adenocarcinoma, serous ovarian carcinoma samples can be delineated with a sensitivity of 97.3%.

CONCLUSION AND CLINICAL RELEVANCE

These preliminary results highlight that MALDI-IMS allows subtyping of malignant effusions to identify the precise origin of neoplastic cells. While achieving similar results compared to classical approaches such as immunocytology, more material is conserved that will be available for further tests.

Diagnostic value of thyroid transcription factor-1 for pleural or other serous metastases of pulmonary adenocarcinoma: a meta-analysis

The role of thyroid transcription factor 1 (TTF-1) in the diagnosis of metastatic pulmonary adenocarcinomas in pleural, pericardial, and peritoneal effusions has not been defined. This study aimed to assess the overall diagnostic accuracy of TTF-1 for metastatic pulmonary adenocarcinomas in pleural or other effusions. Literature search was conducted in PubMed, EMBASE, and other databases to find eligible publications. Quality was assessed according to standardized QUADAS-2 criteria. Sensitivity, specificity, positive/negative likelihood ratio (PLR/NLR), and diagnostic odds ratio (DOR) were pooled. Summary receiver operating characteristic (SROC) curves were used to assess overall performance of the TTF-1 assay. A systematic search revealed 20 studies comprising a total of 1,213 subjects in this meta-analysis. The summary estimates were listed as follows: sensitivity, 0.74 (95% CI: 0.69–0.79); specificity, 0.99 (95% CI: 0.97–1.00); PLR, 78.16 (95% CI: 27.15–225.05); NLR, 0.26 (95% CI: 0.22–0.32); and diagnostic odds ratio, 297.75 (95% CI: 104.16–851.19). Estimated positive and negative post-probability values for metastatic pulmonary adenocarcinomas prevalence of 20% were 95% and 6%, respectively. The area under the SROC curve was 0.96. TTF-1 shows significant potential as a diagnostic marker to differentiate metastatic pulmonary from non-pulmonary adenocarcinomas in pleural or other effusions. These results justify larger, more rigorous studies to confirm such a diagnostic role.

Review: Cell Dynamics in Malignant Pleural Effusions

Malignant pleural effusions (MPEs) are a common manifestation found in patients with lung cancer. After cytological and histological confirmation of malignancy, talc pleurodesis still remains the treatment of choice in patients with MPEs resistant to chemotherapy. Despite this, primary challenges include reduced quality of life and life expectancy in general. Therefore, a better understanding of the cell biology of MPEs, along with improvements in treatment is greatly needed. It has recently been demonstrated that MPEs may represent an excellent source for identification of molecular mechanisms within the tumor and its environment. The present review summarizes the current understanding of MPEs cells and tumor microenvironment, and particularly focuses on dissecting the cross-talk between MPEs and epithelial to mesenchymal transition (EMT), inflammation and cancer stem cells.

CEA, AFP, CA125, CA153 and CA199 in malignant pleural effusions predict the cause

Determination of the cause of malignant pleural effusions is important for treatment and management, especially in cases of unknown primaries. There are limited biomarkers available for prediction of the cause of malignant pleural effusion in clinical practice. Hence, we evaluated pleural levels of five tumor biomarkers (CEA, AFP, CA125, CA153 and CA199) in predicting the cause of malignant pleural effusion in a retrospective study. Kruskal-Wallis or Mann-Whitney U tests were carried out to compare levels of tumor markers in pleural effusion among different forms of neoplasia - lung squamous cell carcinoma, adenocarcinoma, or small cell carcinoma, mesothelioma, breast cancer, lymphoma/leukemia and miscellaneous. Receiver operator characteristic analysis was performed to evaluate sensitivity and specificity of biomarkers. The Kruskal-Wallis test showed significant differences in levels of pleural effusion CEA (P<0.01), AFP (P<0.01), CA153 (P<0.01) and CA199 (P<0.01), but not CA125 (P>0.05), among the seven groups. Receiver operator characteristic analysis showed that, compared with other four tumor markers, CA153 was the best biomarker in diagnosing malignant pleural effusions of lung adenocarcinoma (area under curve (AUC): 0.838 (95%confidence interval: 0.787, 0.888); cut-off value: 10.2U/ ml; sensitivity: 73.2% (64.4-80.8)%, specificity: 85.2% (77.8-90.8)%), lung squamous cell carcinoma (AUC: 0.716 (0.652, 0.780); cut-off value: 14.2U/ml; sensitivity: 57.6% (50.7-64.3)%, specificity: 91.2% (76.3-98.0)%), and small-cell lung cancer (AUC: 0.812 (0.740, 0.884); cut-off value: 9.7U/ml; sensitivity: 61.5% (55.0-67.8)%, specificity: 94.1% (71.2-99.0)%); CEA was the best biomarker in diagnosing MPEs of mesothelioma (AUC: 0.726 (0.593, 0.858); cut-off value: 1.43ng/ml; sensitivity: 83.7% (78.3-88.2)%, specificity: 61.1% (35.8-82.6)%) and lymphoma/leukemia (AUC: 0.923 (0.872, 0.974); cut-off value: 1.71ng/ml; sensitivity: 82.8% (77.4-87.3)%, specificity: 92.3% (63.9-98.7)%). Thus CA153 and CEA appear to be good biomarkers in diagnosing different causes of malignant pleural effusion. Our findings implied that the two tumor markers may improve the diagnosis and treatment for effusions of unknown primaries.

Lung cancer coexisting with ipsilateral pleural effusion

SUMMARY 

Invasion beyond the elastic layer of the visceral pleura and/or diffuse pleural metastatic spread affects negatively survival in lung cancer. Presence of pleural effusion is also associated with poor prognosis, and image techniques can be of great help for diagnosis. When pleural fluid cytology is negative, thoracoscopy is advisable before attempting tumor resection, in order to detect unsuspected pleural metastases. If widespread pleural malignancy is confirmed, chemical pleurodesis using graded talc (with particles larger than 20 µm in diameter) is the best option, unless the lung is unable to re-expand. In this case, or when a previous pleurodesis has failed, or there is a short life expectancy, placement of a indwelling pleural catheter is the treatment of choice.

Metastasis in central nervous system: Clinicopathological study with review of literature in a tertiary care center in South India

BACKGROUND

Secondary central nervous system (CNS) tumors are common in Western countries, but in Indian literature, scant data are available. With the advent of newer imaging techniques, the confirmatory histopathological diagnosis has become comparatively easier. Hereby, we have analyzed our data from a single tertiary care center in south India.

MATERIALS AND METHODS

In this retrospective study from January 2000 to December 2010, histopathologically diagnosed secondary CNS tumors were reviewed along with clinical, imaging, and relevant immunohistochemical findings. Meningeal, lymphoproliferative, and myeloproliferative tumors and autopsy data were not included in the study group.

RESULTS

There were 40 secondary CNS tumors. Male to female ratio was 2.3:1. Age range was wide (28-75 years). Majority of cases were seen in the fourth and fifth decade. Imaging-wise, (computed tomography and magnetic resonance imaging) majority were single lesions (n = 34, 85%). Most commonly, these single lesions were present in the cerebral hemisphere (n = 20, 50%) followed by cerebellum (n = 10, 25%). Adenocarcinoma accounted for maximum number of cases (n = 25, 62.5%) with lungs being the most common primary.

CONCLUSION

We have noted 25% metastatic adenocarcinomas in cerebellar location, which is higher when compared with available world literature. However, we also encountered a good number of cases (30%) due to unknown primary. Though histopathological examination with use of immunohistochemical markers can reliably distinguish primary from secondary CNS tumors in addition to available clinical and imaging data, particularly in developing countries, still a better work-up with an array of immunohistochemical markers and newer imaging modalities is desirable.

Diagnostic value of interleukin 21 and carcinoembryonic antigen levels in malignant pleural effusions

The aim of this study was to evaluate the diagnostic value of interleukin 21 (IL-21) and carcinoembryonic antigen (CEA) in tuberculous pleural effusions (TPEs) and malignant pleural effusions (MPEs). Pleural effusion samples from 103 patients were classified on the basis of diagnosis as TPE (n=51) and MPE (n=52). The concentration of IL-21 was determined by ELISA. Lactate dehydrogenase (LDH), adenosine dehydrogenase (ADA) and CEA levels were also determined in all patients. A significant difference was observed in the levels of ADA and CEA (P<0.01), but not in the levels of LDH (P>0.05) between TPE and MPE. The concentration of IL-21 in MPE was significantly higher compared to TPE (P<0.01). With a threshold value of 4.32 pg/ml, IL-21 had a sensitivity of 76.9% (40/52) and a specificity of 80.4% (41/51). Combined detection of IL-21 and CEA had a sensitivity of 69.2% (36/52) and a specificity of 92.2% (47/51). These two markers can contribute to the differential diagnosis of MPEs.

Current and future options for the diagnosis of malignant pleural effusion

INTRODUCTION

Malignant pleural effusion (MPE) is a frequent problem faced by clinicians, but tumor pleural involvement can be seen without effusion.

AREAS COVERED

Imaging, pleural fluid analysis, biomarkers for MPE, needle pleural biopsy and thoracoscopy. To prepare this review, we performed a search using keywords: 'diagnosis' + 'malignant' + 'pleural' + 'effusion' (all fields) in PubMed, and found 4106 articles overall (until 16 January 2013, 881 in the last 5 years).

EXPERT OPINION

Ultrasound techniques will stay as valuable tools for pleural effusions. Biomarkers in pleural fluid do not currently provide an acceptable yield for MPE. In subjects with past history of asbestos exposure, some serum or plasma markers (soluble mesothelin, fibulin) might help in selecting cases for close follow-up, to detect mesothelioma early. Needle pleural biopsy is justified only if used with image-techniques (ultrasound or CT) guidance, and thoracoscopy is better for both diagnosis and immediate palliative treatment (pleurodesis). Animal models of MPE and 'spheroids' are promising for research involving both pathophysiology and therapy. Considering the possibility of direct pleural delivery of nanotechnology-developed compounds-fit to both diagnosis and therapy purposes ('theranostics')-MPE and mesothelioma in particular are likely to benefit sooner than later from this exciting perspective.

Carcinoma of unknown primary: key radiological issues from the recent National Institute for Health and Clinical Excellence guidelines

Carcinoma of unknown primary origin (CUP) accounts for 3-5% of cancer cases and is the fourth most common cause of cancer death in the UK. CUP management is challenging, partly owing to the heterogeneity of the condition and its presentation, but also owing to the lack of dedicated clinical services for these patients. The recent National Institute for Health and Clinical Excellence (NICE) guidelines on metastatic malignancy of unknown primary origin were developed to improve the co-ordination of diagnostic and clinical services at hospitals treating cancer patients in England and Wales, in particular by the setting up of CUP teams to manage these patients. Radiologists have a vital role in the diagnosis of these patients and should work closely with the CUP team to streamline the diagnostic pathway. This article summarises areas of the NICE guidelines relevant to radiology and discusses the radiological management of patients with CUP, including initial investigation, the importance of biopsy, the management of specific presentations, special investigations and organisational issues.

Pleural fluid analysis: standstill or a work in progress?

Pleural fluid analysis yields important diagnostic information in pleural effusions in combination with clinical history, examination, and radiology. For more than 30 years, the initial and most pragmatic step in this process is to determine whether the fluid is a transudate or an exudate. Light's criteria remain the most robust in separating the transudate-exudate classification which dictates further investigations or management. Recent studies have led to the evaluation and implementation of a number of additional fluid analyses that may improve the diagnostic utility of this method. This paper discusses the current practice and future direction of pleural fluid analysis in determining the aetiology of a pleural effusion. While this has been performed for a few decades, a number of other pleural characteristics are becoming available suggesting that this diagnostic tool is indeed a work in progress.

Clinical verification of the performance of the pathwork tissue of origin test: utility and limitations

Gene expression-based assays have been introduced into the clinical arena to assist in the diagnosis of poorly differentiated or undifferentiated tumors. The US Food and Drug Administration has cleared the microarray-based Pathwork Tissue of Origin (TOO) Test (Pathwork Diagnostics, Sunnyvale, CA) for the molecular characterization of such challenging specimens. We aimed at verifying the analytic and clinical performance of this test on 43 poorly differentiated and undifferentiated tumor samples, including 6 off-panel cases and 7 cancers of unknown primary (CUP). Our results showed 97% (95% confidence interval, 80.4%-99.8%) agreement between the Pathwork TOO Test result and the complete diagnosis, which included clinical correlations and immunohistochemical staining, after the original diagnosis. We concluded that for off-panel and CUP samples, the tissue type and the cell type may be confounded by the Pathwork TOO Test and that careful clinicopathologic assessment is needed when interpreting results from this helpful ancillary tool for pathologists.

Comparing ascitic aspirate and tissue biopsy in the diagnosis of ovarian malignancy

The objective of this retrospective study was to assess the role of tissue biopsy in ovarian cancer where a diagnosis had been made from cytological assessment of ascites. A total of 63 women had been coded for ovarian carcinoma during the period; 48 had undergone cytological or histological investigation, of which six had undergone tissue biopsy, despite having had a cytological diagnosis. In all six cases (100%), the tissue biopsy concurred with the original diagnosis. We conclude that, where a clinically- and radiologically-correlated cytological diagnosis is made, the benefits of an invasive procedure to obtain tissue samples do not outweigh the risks to the patient.

Diagnostic molecular biomarkers for malignant pleural effusions

Malignant pleural effusions (MPEs) are a common and important cause of cancer-related mortality and morbidity. Prompt diagnosis using minimally invasive tests is important because the median survival after diagnosis is only 4–9 months. Pleural fluid cytology is pivotal to current MPE diagnostic algorithms but has limited sensitivity (30–60%). Consequently, many patients need to undergo invasive diagnostic tests such as thoracoscopic pleural biopsy. Recent genomic, transcriptomic, methylation and proteomic studies on cells within pleural effusions have identified novel molecular diagnostic biomarkers that demonstrate potential in complementing cytology in the diagnosis of MPEs. Several challenges will need to be addressed prior to the incorporation of these molecular tests into routine clinical diagnosis, including validation of molecular diagnostic markers in well-designed prospective, comparative and cost–effectiveness studies. Ultimately, minimally invasive diagnostic tests that can be performed quickly will enable clinicians to provide the most effective therapies for patients with MPEs in a timely fashion.

[Immunocytochemical identification of carcinomas of unknown primaries on fine-needle-aspiration-biopsies]

Clinical investigations with imaging- and endoscopic techniques in order to identify the primary tumor sites in patients with CUP syndrome generally entail a significant diagnostic effort. If costs exceed <euro> 800.00, a financial loss ensues for German hospitals, as public health insurance companies do not reimburse above this amount. Combined cytological/immunocytochemical investigation of metastatic cancer cells represents a cost-effective, minimally invasive procedure to identify the probable primary cancer site that can be applied on an outpatient basis. We report on 85 fine needle aspiration biopsies of metastases to the liver, 30 to the lymph nodes and over 180 serous effusions and/or ascites with metastatic cancer cells in CUP. After conventional microscopic inspection, a routine panel of six monoclonal antibodies was applied (CK 5/6, CK 7, CK 20, Cdx 2, TTF 1 and CA 125). We were thus able to correctly identify the primary tumor sites in 90.3%, 92.0% and 85.1%, respectively, within three days. In total, 23 primary hepatocellular carcinomas could all be classified correctly, applying the antibodies HepPar 1, BerEp 4, AFP, CD 31, CD 68 and Ki 67. In addition, 141 malignant epithelial mesotheliomas were typed correctly in 97.1%, using the antibodies BerEp 4, Calretinin, Mesothelin, EMA and WT. Therefore, immunocytochemical investigation of metastatic cancer cells from fine needle aspiration biopsies or in serous effusions offers an efficient, cost-effective diagnostic alternative to imaging and endoscopic techniques in the workup of patients with CUP syndrome.

Pax8: a marker for carcinoma of Müllerian origin in serous effusions

PAX8 is a nuclear transcription factor with limited expression in normal and neoplastic tissues in a cell lineage-dependent manner. PAX8 has been detected in embryonic Müllerian ducts, human fallopian tubes, and ovarian carcinomas. However, little is known about its expression in other areas of the female genital tract. In this study, we used immunohistochemistry (IHC) to examine PAX8 expression in the normal uterine corpus and cervix, malignant tumors arising from these sites, and malignant effusions. We reported here that PAX8 was also detected in endometrial epithelial cells and endocervical glands, with a lower expression level in the latter, but not in the stromal cells of these areas. All endometrial carcinomas (N = 52) were positive for PAX8, whereas endocervical adenocarcinomas (N = 5) and uterine leiomyosarcomas (N = 3) were negative for PAX8. PAX8 was detected in 70% (22/31) and 68.8% (11/16) of metastatic carcinomas of the ovary and endometrium in serous effusions, respectively. No PAX8 was detected in carcinomas of nongynecologic origin or noncarcinomas (N = 71) in serous effusions except in one renal-cell carcinoma and one carcinoma of unknown primary in a woman. In addition, papillary serous carcinomas of the peritoneum (N = 10) were diffusely positive for PAX8, implying a Müllerian origin similar to malignant tumors in the female genital tract. Our findings suggest that PAX8 is an additional IHC marker for carcinomas of Müllerian origin hence we recommend including PAX8 for evaluation of malignant serous effusions in women, especially when tumors of Müllerian origin are in the differential diagnosis.

Evidence-based guidelines to optimize the selection of antibody panels in cytopathology: pleural effusions with malignant epithelioid cells

There is no established methodology to help select cost effective antibody panels. We used Bayesian statistics and an evidence-based pathology (EBP) approach to retrospectively review the use of immunohistochemistry (IHC) in 153 consecutive pleural effusions evaluated in our laboratory from 2005-2007 for the differential diagnosis of malignant mesothelial cells versus carcinoma cells and to estimate the likely site of origin of a carcinoma. The results in this "training" set were used to design antibody panels and test their clinical applicability on a "test set" of 44 pleural effusions collected in early 2008. Cytopathologists had used 6 +/- 4.5 IHC tests per case for the diagnosis of malignant mesothelioma (n = 9) and carcinomas of lung (n = 60), breast (n = 47), Müllerian (n = 25), and other origins in the "training set". The sensitivity and specificity of pleural cytology using all these IHC tests were 32% and 95%, respectively. Sensitivity, specificity and post-test odds (PTO) of a positive IHC result were calculated for each antibody and by the following classes: malignant mesothelial cells and carcinoma cells by primary site of origin. The antibodies that provided the best PTO to diagnose the most prevalent tumors in our population were included in diagnostic panels for male (calretinin, TTF-1, PSA and CDX-2) and female (calretinin, TTF-1, ER and CA125) patients. These panels provided 100% specificity and 77% and 50% sensitivity, respectively, for the pleural effusions from female and male patients in the "test set." The use of an EBP approach for test selection in cytopathology is discussed.

Immunocytochemical typing of primary tumors on fine-needle aspiration cytologies of lymph nodes

The aim of this study was to analyze the role of immunocytochemistry as an ancillary method on routine FNACs of enlarged lymph nodes, using different markers. In a validating cohort study all patients had confirmatory histological and/or clinical follow-up. 10 FNACs were analyzed for the differentiation of Non-Hodgkin Lymphoma (NHL) from metastatic carcinoma (MC), 30 cases to identify the sites of metastatic unknown primary tumors and 16 cases were checked to confirm clinical suspicion of a specific MC. Accuracy to differentiate NHL from MC was 100%, 92.3% to identify a primary tumor site of MC, and 100% to confirm a clinical suspicion of a specific MC. In 7 cases, the site of the primary tumor remained clinically unknown. Application of immunocytochemical markers on the same slide used for microscopic diagnosis is a useful tool in the routine assessment of FNACs of lymph nodes.

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.

[Pericardial cytopathology]

Cytopathology diagnosis of three hundred and thirty three pericardial effusions performed between September 1999 and August 2006 were systematically analyzed and compared with the biopsy in 71 cases. We described the clinical circumstances, the etiologies, the cytomorphologic features of the effusions, the role of liquid based cytology and ancillary studies such as immunocytochemistry and the sensitivity of cytopathology compared with histopathology. Among the 57 pericardial tumors, 51 (89%) were metastatic carcinomas--included 42 (73%) adenocarcinomas--, 5 (9%) were malignant lymphomas and one (2%) was a malignant mesothelioma. Cytology of pericardial effusion with ancillary studies enables rapid cytodiagnosis as specific as histodiagnosis provided by biopsy.