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

A Microfluidic System for Detecting Tumor Cells Based on Biomarker Hexaminolevulinate (HAL): Applications in Pleural Effusion

Malignant pleural effusion is a common clinical problem, which often occurs in cases of malignant tumors, especially in lung cancer. In this paper, a pleural effusion detection system based on a microfluidic chip, combined with specific tumor biomarker, hexaminolevulinate (HAL), used to concentrate and identify tumor cells in pleural effusion was reported. The lung adenocarcinoma cell line A549 and mesothelial cell line Met-5A were cultured as the tumor cells and non-tumor cells, respectively. The optimum enrichment effect was achieved in the microfluidic chip when the flow rates of cell suspension and phosphate-buffered saline achieved 2 mL/h and 4 mL/h, respectively. At the optimal flow rate, the proportion of A549 increased from 28.04% to 70.01% due to the concentration effect of the chip, indicating that tumor cells could be enriched by a factor of 2.5 times. In addition, HAL staining results revealed that HAL can be used to identify tumor cells and non-tumor cells in chip and clinical samples. Additionally, the tumor cells obtained from the patients diagnosed with lung cancer were confirmed to be captured in the microfluidic chip, proving the validity of the microfluidic detection system. This study preliminarily demonstrates the microfluidic system is a promising method with which to assist clinical detection in pleural effusion.

Deep Learning-Based Classification and Targeted Gene Alteration Prediction from Pleural Effusion Cell Block Whole-Slide Images

Cytopathological examination is one of the main examinations for pleural effusion, and especially for many patients with advanced cancer, pleural effusion is the only accessible specimen for establishing a pathological diagnosis. The lack of cytopathologists and the high cost of gene detection present opportunities for the application of deep learning. In this retrospective analysis, data representing 1321 consecutive cases of pleural effusion were collected. We trained and evaluated our deep learning model based on several tasks, including the diagnosis of benign and malignant pleural effusion, the identification of the primary location of common metastatic cancer from pleural effusion, and the prediction of genetic alterations associated with targeted therapy. We achieved good results in identifying benign and malignant pleural effusions (0.932 AUC (area under the ROC curve)) and the primary location of common metastatic cancer (0.910 AUC). In addition, we analyzed ten genes related to targeted therapy in specimens and used them to train the model regarding four alteration statuses, which also yielded reasonable results (0.869 AUC for ALK fusion, 0.804 AUC for KRAS mutation, 0.644 AUC for EGFR mutation and 0.774 AUC for NONE alteration). Our research shows the feasibility and benefits of deep learning to assist in cytopathological diagnosis in clinical settings.

A Combat Journey With Pulmonary Rehabilitation and Palliative Care in a Patient With Pleural Effusion, Secondary to Metaplastic Breast Carcinoma

Metaplastic breast cancer is an uncommon and fatal condition. It is described histologically as a tumor having epithelial differentiation into squamous and mesenchymal components, with numerous elements frequently co-existing in the same tumor. This case study sought to provide analgesic treatment in a case with malignant pleural effusion related to breast cancer based on evidence. A 67-year-old female with a known history of metaplastic breast carcinoma came to the tertiary care hospital with complaints of breathlessness which progressed to grade II on the Modified Medical Research Council (mMRC) Dyspnoea Scale, a cough with mucoid expectoration, restlessness, nausea, and reduced appetite for eight days. Diagnostic findings revealed bilateral pleural effusion (left>right). Laboratory investigations revealed that the excess fluid accumulated was transudate in nature, according to the Light's criteria. This case report illustrates the strategy, management, and importance of adherence to pulmonary rehabilitation and painkiller care physiotherapy for patients with metaplastic breast cancer and pleural effusion to achieve the best possible physical and mental health.

Application of the international system for reporting serous fluid cytopathology on reporting various body fluids; experience of a tertiary care hospital

Objectives:

Cytological examination of effusion sample is a preliminary and minimally invasive method for the diagnosis of body fluids. Recently, the International System For Reporting Serous Fluid Cytopathology (ISRSFC) and the Indian Academy of Cytologist (IAC) have published guidelines for reporting effusion cytology and calculating the risks of malignancy (ROMs) for each defined category. We report our 2 years of experience in reclassifying and assessing the feasibility of applying ISRFSC and IAC categories to effusion fluid and to provide an estimate of the risk of malignancy for each diagnostic category.

Material and Methods:

Cytological reports of patients from January 2019 to December 2020 were retrieved and reclassified into a five-tiered classification scheme as per ISRSFC guidelines. Cellblock and immunohistochemistry were performed in selected cases. Clinico radiological and histopathological information were obtained and correlated with the cytological findings wherever available.

Results:

In the study, 652 cases were included during the 2 years. Out of these, 328 (50.3%) were women and 314 (47.3%) were men. Patient’s ages ranged between 2 92 years with a mean age of 47.4 years. There were 366 (56.1%) cases of ascitic fluid followed by 262 (40.1%) cases of pleural fluid and 24 (3.8%) cases of pericardial fluid in the analysis. Of all the cases, 13 (2%) were non-diagnostic (ND), 464 (71.6%) were negative for malignant (NFM) cells, 16 (2.4%) were atypia of uncertain significance, 31 (4.7%) were suspicious of malignancy, and 125 (19.3%) were malignant. Cellblock was prepared in 65 cases. Lung cancer followed by breast cancer was the most common malignancies involving the pleural effusion and ovarian cancer was the most common cause of peritoneal effusion. ROM for each diagnostic category was 23% for ND, 25% for NFM, 56% for the atypical category, 80.6% in suspicious, and 90% were for positive for malignancy category.

Conclusion:

The use of a five-tiered system as per the ISRFC and IAC guidelines are feasible for the standardized reporting of effusion samples, thus avoiding subjective variation of reporting.

Initial panel of immunocytochemical markers for identification of primary carcinoma site for effusions and peritoneal washings from women

INTRODUCTION

In women, most malignant effusions are from breast and ovary primary carcinomas that have metastasized to body cavity fluids (pleural, peritoneal and pericardial). When carcinoma is diagnosed in effusions, it is not possible to identify its site of origin solely by cytology (morphology); therefore, immunocytochemistry is used as a complementary method. There are no immunocytochemical markers with 100% sensitivity and specificity for identifying carcinoma primary site. The markers most used are TTF-1 for the lung, GATA-3 for the breast, and PAX-8 for the ovary. The aim of this study was to evaluate the sensitivity and specificity of a panel including these markers for detecting the primary site of carcinoma in effusions.

METHODS

Samples of pleural, pericardial, and peritoneal effusions and peritoneal washings with carcinoma of known primary site from women (n = 60) and men (n = 18) were prepared by using the cell block method, and immunocytochemistry was performed to evaluate the expression of primary site markers (TTF-1, PAX-8, and GATA-3).

RESULTS

In women, the breast was the most frequent primary site of metastatic carcinoma to both pleural and pericardial cavities, followed by the lung, whereas the ovary was the most frequent primary site of carcinoma within peritoneal effusions and washings, followed by the gastrointestinal tract (stomach or intestine). The expected profiles for carcinomas of the most common primary sites were: breast (GATA-3 (+), PAX-8 (-), TTF-1 (-)), ovary (PAX-8 (+), GATA-3 (-), TTF-1 (-)), lung (TTF-1 (+), PAX-8 (-) GATA-3 (-)) and gastrointestinal tract (PAX-8 (-), GATA-3 (-), TTF-1 (-)). These were observed in 88.23% (45/51) of women's samples with carcinoma from these primary sites. By using TTF-1 as the sole primary site marker, 6.25% of carcinomas of primary site other than the lung would have been misdiagnosed.

CONCLUSION

An initial panel of markers including GATA-3, PAX-8, and TTF-1 allows, with high sensitivity and specificity, the identification or exclusion of frequent primary sites of carcinoma in effusions from women. Our results highlight the importance of using a panel of markers to avoid misidentification of the primary site of tumor.

Diagnostic value of periostin in lung cancer-related malignant pleural effusion

BACKGROUND

Periostin (POSTN) is an extracellular matrix protein that is overexpressed in lung cancer and is considered an effective diagnostic and prognostic biomarker for lung cancer. The purpose of this study was to investigate the diagnostic performance of POSTN and to further evaluate the diagnostic value of POSTN combined with carcinoembryonic antigen (CEA) and cancer ratio [CR: serum lactate dehydrogenase (LDH)/pleural effusion adenosine deaminase (PE ADA)] in lung cancer-related malignant PE (MPE).

METHODS

A total of 108 patients with PE, including 54 with lung cancer and 54 with benign lung disease, were enrolled in this study. The POSTN levels of PE and serum were detected using an enzyme-linked immunosorbent assay. Information on the expression of PE and serum CEA, serum LDH, and PE ADA was collected from medical records.

RESULTS

The levels of PE POSTN in MPE of patients with lung cancer were significantly higher than those in patients with benign PE (p < 0.0001). The receiver operating characteristic (ROC) curve indicated that the diagnostic sensitivity and specificity of PE POSTN for lung cancer-related MPE were respectively 77.78% and 68.52% when the cutoff value was determined to be 53.45 ng/ml. The ROC curve analysis demonstrated that PE POSTN has a high diagnostic value in MPE associated with lung cancer [area under the curve (AUC) = 0.764], and the combination of PE POSTN, PE CEA, and CR can improve the diagnostic accuracy of lung cancer-related MPE (AUC = 0.948).

CONCLUSION

POSTN can be used as a potential marker for lung cancer-related MPE diagnosis.

Categorisation of serous effusions using the International System for Reporting Serous Fluid Cytopathology and assessment of risk of malignancy with diagnostic accuracy

CONTEXT

The International System for Reporting Serous Fluid Cytopathology (ISRSFC) standardises the reporting of serous effusion cytology under five categories: Non-Diagnostic (ND), Negative for Malignancy (NFM), Atypia of Undetermined Significance (AUS), Suspicious for Malignancy (SFM), and Malignant (M). Very few studies have been conducted so far to confirm the risk of malignancy of the different categories.

AIMS

The main objectives of our study were to classify serous effusions according to the ISRSFC categories and assess their risk of malignancy (ROM) and performance parameters.

MATERIALS AND METHODS

All serous effusion samples received from January 2019 to December 2020 were reclassified according to the ISRSFC. Using histopathological diagnosis as the gold standard, ROM and performance parameters were calculated.

RESULTS

A total of 831 pleural effusion samples were reclassified as follows: ND, 3 (0.4%); NFM, 635 (76.4%); AUS, 65 (7.8%); SFM, 60 (7.2%); and M, 68 (8.2%). For 457 peritoneal effusion samples, the reclassifications were ND, 5 (1.1%); NFM, 368 (80.5%); AUS, 19 (4.2%); SFM, 17 (3.7%); and M, 48 (10.5%). All 12 (100%) pericardial effusions belonged to the NFM category. The ROM for the ND, NFM, AUS, SRM, and M categories was 0%, 2.1%, 33.3%, 94.1%, 100%, respectively, in pleural effusions, and 50%, 4.8%, 22.2%, 83.3%, 100%, respectively, in peritoneal effusions. The ROM was 0% for NFM in pericardial effusions.

CONCLUSION

The ISRSFC is an excellent system for accurately classifying serous effusions with greater reproducibility of reports and better communication between pathologist and clinician.

90-Gene Expression Profiling for Tissue Origin Diagnosis of Cancer of Unknown Primary

Cancer of unknown primary (CUP), in which metastatic diseases exist without an identifiable primary location, accounts for about 3-5% of all cancer diagnoses. Successful diagnosis and treatment of such patients are difficult. This study aimed to assess the expression characteristics of 90 genes as a method of identifying the primary site from CUP samples. We validated a 90-gene expression assay and explored its potential diagnostic utility in 44 patients at Jiangsu Cancer Hospital. For each specimen, the expression of 90 tumor-specific genes in malignant tumors was analyzed, and similarity scores were obtained. The types of malignant tumors predicted were compared with the reference diagnosis to calculate the accuracy. In addition, we verified the consistency of the expression profiles of the 90 genes in CUP secondary malignancies and metastatic malignancies in The Cancer Genome Atlas. We also reported a detailed description of the next-generation coding sequences for CUP patients. For each clinical medical specimen collected, the type of malignant tumor predicted and analyzed by the 90-gene expression assay was compared with its reference diagnosis, and the overall accuracy was 95.4%. In addition, the 90-gene expression profile generally accurately classified CUP into the cluster of its primary tumor. Sequencing of the exome transcriptome containing 556 high-frequency gene mutation oncogenes was not significantly related to the 90 genes analysis. Our results demonstrate that the expression characteristics of these 90 genes can be used as a powerful tool to accurately identify the primary sites of CUP. In the future, the inclusion of the 90-gene expression assay in pathological diagnosis will help oncologists use precise treatments, thereby improving the care and outcomes of CUP patients.

Cellular composition research of serous pleural effusion fluids. Conceptual issues of preanalytics

The purpose of this work was to show the effectiveness of the cytological method on a small number of observations, excluding all possible errors of the preanalytical stage. The paper presents several simple and easily reproducible algorithms for the cytological study of serous pleural effusions with small cellular content. On the example of 20 observations of the study of the cellular composition of serous exudates, a direct dependence of the research results on the preanalytical stage is shown. A complete study of effusion fluids in compliance with all stages of preanalytics and the use of modern methods of cytological diagnostics makes it possible to nullify the options for false-negative.

Application of Indian Academy of Cytologists Guidelines for Reporting Serous Effusions: An Institutional Experience

Background:

Recently, the Indian Academy of Cytologists (IAC) has published the guidelines for interpretation and reporting of serous effusions. Till date, there are no studies on its applicability.

Aims:

The present study was carried out to assess the feasibility of applying the IAC reporting categories to effusions, determine the frequency, and provide an estimate of the risk of malignancy (ROM) for individual diagnostic categories.

Materials and Methods:

All cases of serous effusion fluids reported in the year 2019 were retrieved from the archives and reassigned as per the IAC diagnostic categories. The clinical and histopathological follow-up information was obtained wherever possible.

Results:

A total of 1340 effusion samples were received from 1085 patients. There were 561 (51.7%) males and 524 (48.3%) females. Majority were pleural (1066, 79.5%), followed by peritoneal (187, 14%) and pericardial (87, 6.5%) effusions. The age ranged from 7 months to 92 years. There were 35 (2.6%) samples in category 1 (non-diagnostic), 954 (71.2%) in category 2 (benign), 17 (1.3%) in category 3 (atypical), 59 (4.4%) in category 4 (suspicious for malignancy) and 275 (20.5%) in category 5 (malignant). The estimated ROM in serous effusion samples was 20% for category 1, 16.7% for category 2, 50% for category 3, 94.4% for category 4 and 100% for category 5.

Conclusions:

The categorization of serous effusion cytology samples as per the IAC diagnostic categories and as per the reporting format developed by the IAC is feasible and the management recommendations are mostly appropriate.

Medical Thoracoscopy for the Management of Exudative Pleural Effusion: A Retrospective Study

Objective

The aim of this study was to evaluate the efficacy of medical thoracoscopy in the diagnosis and treatment of exudative pleural effusion.

Methods

A total of 82 patients with exudative pleural effusion underwent medical thoracoscopy under local anesthesia and mild sedation. The clinical characteristics, pleural fluid routine and biochemical tests, pleural biopsy, and outcomes were retrospectively evaluated.

Results

Among 82 patients, the color and transparency of pleural fluid and the levels of white blood cells (WBC), lactate dehydrogenase (LDH), neutrophil proportion, lymphocyte proportion, adenosine deaminase (ADA), and glucose were different among tuberculosis (TB), malignant (M), acute and chronic inflammation (ACI), and purulent (P) cases. Furthermore, 70% of M cases had a low positive rate of exfoliated cells in the sputum and pleural fluid, and more than 90% of TB cases had low positive rates of anti-tuberculosis antibodies and acid-fast bacilli in the sputum and pleural fluid. Pleural biopsy showed that 11% of cases were M, 74.4% were TB, 11% were ACI, and 3.6% were P. Medical thoracoscopy showed that 66.7% of ACI cases had pleural adhesions, 34.4% of TB cases had moderate and 34.4% of TB cases had severe pleural adhesions, 100% of M and TB cases had pleural surface nodules and 77.8% of ACI cases had pleural surface nodules, 49.2% of TB cases showed encapsulated pleural effusion, and 33.3% of M cases showed encapsulated pleural effusion.

Conclusion

Medical thoracoscopy has high feasibility and accuracy in the diagnosis and treatment of exudative pleural effusion.

Liquid biopsy approaches for pleural effusion in lung cancer patients

Genomic profiling of tumors has become the mainstay for diagnosis, treatment monitoring and a guide to precision medicine. However, in clinical practice, the detection of driver mutations in tumors has several procedural limitations owing to progressive disease and tumor heterogeneity. The current era of liquid biopsy promises a better solution. This diagnostic utility of liquid biopsy has been demonstrated by numerous studies for the detection of cell-free DNA (cfDNA) in plasma for disease diagnosis, prognosis, and prediction. However, cfDNAs are limited in blood circulation and still hurdles to achieve promising precision medicine. Malignant pleural effusion (MPE) is usually detected in advanced lung malignancy, which is rich in tumor cells. Extracellular vesicles and cfDNAs are the two major targets currently explored using MPE. Therefore, MPE can be used as a source of biomarkers in liquid biopsy for investigating tumor mutations. This review focuses on the liquid biopsy approaches for pleural effusion which may be explored as an alternative source for liquid biopsy in lung cancer patients to diagnose early disease progression.

Cytohistological correlation in serous effusions using the newly proposed International System for Reporting Serous Fluid Cytopathology: Experience of an oncological center

BACKGROUND

Cytological analysis is part of the initial etiological evaluation of serous effusions. The newly proposed International System for Reporting Serous Fluid Cytopathology (ISRSFC) aims to standardize reporting.

METHODS

All pleural and peritoneal effusion samples admitted for cytological analysis at our institution between 2012 and 2016, and pericardial effusion samples admitted between 2008 and 2018, were reviewed and reclassified according to the ISRSFC. Risk of malignancy (ROM) and performance parameters were calculated.

RESULTS

1496 pleural effusion samples were reclassified: 12(0.8%) non-diagnostic (ND), 944(63.1%) negative for malignancy (NFM), 9(0.6%) atypia of undetermined significance (AUS), 54(3.6%) suspicious of malignancy (SFM) and 477(31.9%) malignant (M). 64 pericardial effusion samples were reclassified: 23(35.9%) NFM, 1(1.6%) AUS, 4(6.3%) SFM and 36(56.2%) M. 763 peritoneal effusion samples were reclassified: 5(0.7%) ND, 457(59.9%) NFM, 12(1.6%) AUS, 37(4.8%) SFM and 252(33%) M. The ROM was, respectively, for each of the aforementioned categories, 57.1%, 23.9%, 50%, 76.2%, 100% in pleural effusions, 100%, 26.3%, 62.5%, 91.7%, 100% in peritoneal effusions and 0% for NFM, 0% for AUS and 100% for M in pericardial effusions. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were, respectively, 61.6%, 100%, 100%, 73.3%, 81.3% for pleural, 100%, 100%, 100%, 100%, 100% for pericardial and 61.2%, 100%, 100%, 70%, 79.7% for peritoneal effusion samples.

CONCLUSION

Serous effusion cytology has a high specificity and positive predictive value and a modest sensitivity and negative predictive value, supporting its role in confirming the diagnosis of malignancy. The ISRSFC will increase standardization and reproducibility in reporting, leading to improved clinical decision-making.

Cancer of Unknown Primary Site: Real Entity or Misdiagnosed Disease?

Metastasis is a late event in the progression of any tumour. However, invasive cancers are occasionally detected in the form of metastatic lesions without a clearly detectable primary tumour. Cancer of unknown primary site (CUP) is defined as a confirmed metastatic tumour, with unknown primary tumour site, despite the standardized diagnostic approach that includes clinical history, routine laboratory tests, and complete physical examination. Due to the lack of basic research on its primary causes, CUP is appropriately termed an 'orphan' cancer. Nevertheless, CUP accounts for 2-5% of diagnosed malignancies. To date, it is unclear whether CUP is an entity with primary dormancy as its hallmark or an entity with genetic abnormalities that cause it to manifest as a primary metastatic disease. In this review, we discuss different aspects of CUP, including its current diagnostic methods, angiogenesis effectors, relationship with cancer stem cells and current treatments.