Immunocytochemical expression of a panel of markers in pleural effusions from patients with primary lung adenocarcinoma

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.

Diagnostic accuracy of E-cadherin for malignanteffusions: a systematic review and meta-analysis

BACKGROUND

The differential diagnosis of malignant effusion remains a clinical challenge. We aim to summarise all relevant literature studies in order to determine the overall clinical value of E-cadherin in the diagnosis of malignant effusion by meta-analysis.

METHODS

PubMed, the Cochrane Library Database, Medline (Ovid), Web of Science, CNKI, WANFANG and WEIPU databases are thoroughly searched up to 15 March2018. The calculated pooled sensitivity, specificity, likelihood ratio (LR), diagnostic OR(DOR) and the summary receiver operating characteristic (SROC) curve were plotted.

RESULTS

A total of 15 studies were included in the analysis. The sensitivity and specificity of E-cadherin in the diagnosis of malignant effusion were determined to be high, with a sensitivity of 0.83(95%CI0.79 to 0.87) and a specificity of 0.96(95%CI0.90 to 0.98). The positive LR was determined to be 21.10(95%CI 8.54 to 52.11), the negative LR was determined to be 0.17(95% CI 0.14 to 0.22) and the DOR was determined to be 121.34(95%CI 49.11 to 299.80). The SROC curve exhibited a high overall diagnostic, with the area under the curve measured to be 0.91(95% CI 0.89 to 0.93). Subgroup analysis showed the method (cell blocks or smears), sample size (≥100 or<100), geographical location (Asia, Europe or USA) and impact factor of each article (≥3 or<3) were not the sources of overall heterogeneity.

CONCLUSION

E-cadherin exhibits very good diagnostic accuracy for the diagnosis for malignant effusion; thus, it can be helpful in the process of clinical decisions.