The role of cytologic evaluation of pleural fluid in the diagnosis of malignant mesothelioma

Our plain-English summary of The role of cytologic evaluation of pleural fluid in the diagnosis of malignant mesothelioma, by A.A. Renshaw, B.R. Dean, K.H. Antman, et al (Chest, 1997).

The study

• Authors: A.A. Renshaw, B.R. Dean, K.H. Antman, D.J. Sugarbaker, E.S. Cibas
• Journal: Chest
• Published: 1997;111(1):106-9
• Cited by: 145 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Study Objective: Treatment of malignant mesothelioma (MM) at an early stage results in increased survival. Cytologic examination of pleural effusions is one of the first diagnostic techniques attempted in these patients. The objective of this study was to define the role of cytologic examination of pleural fluid in facilitating early diagnosis.

Design: The medical records and cytologic slides of patients with pleural MM were reviewed.

Setting: Medical records were reviewed from two institutions: a large general hospital and a cancer hospital.

Patients: Twenty-nine patients ranging in age from 32 to 81 years (mean, 59 years) met the study criteria.

Interventions: All patients had at least one cytologic pleural fluid examination.

Measurements And Results: The median time from initial symptoms to the diagnosis of MM was 8 weeks for all patients. For patients with a positive or suspicious cytologic result, the median was 4 weeks, and in those with a negative cytologic result, it was 12 weeks. The overall sensitivity of cytologic examination for the diagnosis of MM was 32%. Cytogenetic analysis of pleural fluid had a sensitivity of 56%, and was positive in 1 case in which results of cytologic examination were negative. Patients in whom the time from presentation to diagnosis was greater than 1 year all had negative cytologic results followed by long periods without further workup, despite a history of exposure to asbestos.

Conclusions: A positive or suspicious cytologic result was associated with a decreased median time to diagnosis. Unfortunately, the sensitivity of cytologic examination for a diagnosis of MM was only 32%. Until better diagnostic techniques are developed, we recommend immediate pleural biopsy in patients in whom MM is suspected and cytologic evaluation of pleural fluid gives negative results.

In plain English

This study reviewed the medical records of 29 patients with pleural malignant mesothelioma referred to two Boston hospitals between December 1990 and January 1992; pleural fluid slides could be re-examined for 13 of them. A pleural biopsy confirmed every diagnosis; 24 tumors were epithelial and 5 sarcomatoid. An asbestos history was recorded for 18 of 29 patients. Of 37 pleural fluid samples, 6 were positive and 6 suspicious, a combined sensitivity of 32%. It rose to 37.5% when the five sarcomatoid cases, all negative, were excluded. Median time from first symptoms to diagnosis was 8 weeks overall, 4 weeks for patients with positive or suspicious cytology, and 12 weeks for those with negative cytology. The three patients whose diagnosis took longer than a year all had asbestos exposure histories and negative cytology. Chromosome analysis was done on 7 fluids. Three gave no result, and four showed abnormalities characteristic of mesothelioma, one of them a fluid with negative cytology. The authors recommended immediate pleural biopsy when mesothelioma is suspected and cytology is negative, until better techniques are developed.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Retrospective review of medical records and cytologic slides (case series)
• Who was studied: 29 patients with pleural malignant mesothelioma, aged 32 to 81 (mean 59), 24 men and 5 women. They came from 20 consecutive patients at Brigham and Women's Hospital and 20 at Dana Farber Cancer Institute, Boston, December 1990 to January 1992. Seven peritoneal cases were excluded and four patients were seen at both hospitals. Tumors were 24 epithelial and 5 sarcomatoid. Pleural fluid slides were available for review for 13 of the 29 patients.
• Exposure: Not an exposure study. An asbestos history was recorded in 18 of 29 patients; fiber types and jobs were not given.
• Main results:
  • First pleural fluid specimens (29 patients): 4 positive (14%), 5 suspicious (17%), 20 negative (69%).
  • Of all 37 thoracenteses, 6 were positive (16%) and 6 suspicious (16%). Combined, the sensitivity of cytology for malignancy was 32%.
  • Excluding the 5 sarcomatoid cases, all of which were negative, sensitivity was 37.5%.
  • Median time from initial symptoms to diagnosis was 8 weeks for all patients.
  • Median time to diagnosis was 4 weeks for patients with positive or suspicious cytology and 12 weeks for those with negative cytology.
  • Extrapleural pneumonectomy followed in 8 of 12 patients with positive or suspicious cytology and in 2 of 17 with negative cytology.
  • The 3 patients whose diagnosis took longer than 1 year all had asbestos exposure histories and pleural effusions read as negative on cytology.
  • Cytogenetic analysis was done on 7 fluids. Three yielded no metaphases, and the other four showed chromosomal abnormalities characteristic of mesothelioma.
  • Among the 4 fluids positive on cytogenetics, cytology had been positive in 2, suspicious in 1 and negative in 1.
  • On review, slides from 13 patients (45%) confirmed the original diagnoses. One case recorded as negative in the medical record had been diagnosed as positive (case 18).
• The authors' conclusion: The authors concluded that a positive or suspicious cytology result was associated with a shorter median time to diagnosis but that cytology sensitivity was only 32%. They attributed negative results to sampling rather than interpretive error. They recommended immediate pleural biopsy when mesothelioma is suspected and cytology is negative, until better diagnostic techniques are developed.
• Limitations the authors state:
  • The study did not address whether some tumors shed too few cells into effusions or whether cells are lost or poorly displayed during specimen processing.
  • For the three women with asbestos exposure histories, it was not known whether the exposure was occupational or bystander.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma, Pleural plaques and thickening.

Medical terms in this study, explained in our Lexicon: Mesothelioma, Pleural Effusion, Pleural Biopsy.

Related studies

• The sensitivity of cytologic evaluation of pleural fluid in the diagnosis of malignant mesothelioma — E.A. Rakha, S. Patil, et al. (2010)
• Evaluation of pleural CYFRA 21-1 and carcinoembryonic antigen in the diagnosis of malignant pleural effusions — G. Salama, M. Miédougé, et al. (1998)
• Evaluation of seven tumour markers in pleural fluid for the diagnosis of malignant effusions — M. Miédougé, P. Rouzaud, et al. (1999)
• Diagnostic use of muscle markers in the cytologic evaluation of serous fluids — A.M. Afify, B.M. Al-Khafaji, et al. (2002)
• Vascular endothelial growth factor in pleural fluid for differential diagnosis of benign and malignant origin and its clinical applications — A. Fiorelli, G. Vicidomini, et al. (2011)
• Hyaluronic acid in the pleural fluid of patients with malignant pleural mesothelioma — N. Fujimoto, K. Gemba, et al. (2013)

Browse more research in Chest, or return to medical research.