Clinical significance of the detection of the homozygous deletion of P16 gene in malignant pleural effusion

Molecular testing on serous effusion: An update

Cytological examination of the effusion fluid provides valuable information regarding the presence of malignancy. At times, it is challenging to diagnose malignant cells in serous effusion. The various ancillary techniques are available to solve the problem including immunocytochemistry, DNA ploidy, and multicolored flow cytometry. At present, the molecular tests on the effusion sample are of growing interest. The effusion sample is rich in cells and cell-free fluid that contains free DNA, cytokines, and extracellular vesicles. Molecular tests in effusion sample not only provide a diagnosis of malignancy but can also give valuable information that may be essential for the individualized therapy, management, and prognostic assessment. In this paper, we reviewed the application of the different molecular tests in the effusion sample.

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.