Abdominopelvic washings: A comprehensive review

Our plain-English summary of Abdominopelvic washings: A comprehensive review, by E.F. Rodriguez, S.E. Monaco, W. Khalbuss, et al (CytoJournal, 2013).

The study

• Authors: E.F. Rodriguez, S.E. Monaco, W. Khalbuss, R.M. Austin, L. Pantanowitz
• Journal: CytoJournal
• Published: 2013;10:7
• Cited by: 30 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Intraperitoneal spread may occur with gynecological epithelial neoplasms, as well as with non-gynecological malignancies, which may result in serosal involvement with or without concomitant effusion. Therefore, washings in patients with abdominopelvic tumors represent important specimens for cytologic examination. They are primarily utilized for staging ovarian cancers, although their role has decreased in staging of endometrial and cervical carcinoma. Abdominopelvic washings can be positive in a variety of pathologic conditions, including benign conditions, borderline neoplastic tumors, locally invasive tumors, or distant metastases. In a subset of cases, washings can be diagnostically challenging due to the presence of co-existing benign cells (e.g., mesothelial hyperplasia, endosalpingiosis, or endometriosis), lesions in which there is only minimal atypia (e.g., serous borderline tumors) or scant atypical cells, and the rarity of specific tumor types (e.g., mesothelioma). Ancillary studies including immunocytochemistry and fluorescence in situ hybridization may be required in difficult cases to resolve the diagnosis. This article provides a comprehensive and contemporary review of abdominopelvic washings in the evaluation of gynecologic and non-gynecologic tumors, including primary peritoneal and mesothelial entities.

In plain English

This article was a review, not a new study. Pathologists at the University of Pittsburgh Medical Center described the microscopic appearance of abdominopelvic washings, fluid rinsed from the abdomen and pelvis during surgery and checked for tumor cells. They covered normal findings, benign look-alikes such as endometriosis, and many gynecologic and non-gynecologic tumors. In a section on mesothelial lesions, they stated that diffuse peritoneal mesothelioma accounts for 10-20% of all mesotheliomas, occurs in women as often as men, typically from secondary exposure to asbestos, and has an average survival of less than 2 years. No fiber type was named. They listed stains that help identify mesothelioma cells. They cited earlier work finding a homozygous CDKN2A (p16) gene deletion, detected by fluorescence in situ hybridization, in over 70% of mesotheliomas. Because the diagnosis is hard in washings and has medical-legal implications, they wrote that without supporting clinical or radiological findings and proper ancillary testing, reporting "atypical mesothelial proliferation" and recommending tissue biopsy is often preferable. The authors concluded that washing findings should be compared with the surgical pathology of the removed tumor in all cases.

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: narrative review of the cytology (microscopic cell appearance) of abdominopelvic washings
• Who was studied: No study population. The review covered abdominopelvic (peritoneal) washing specimens collected during abdominal surgery from patients with gynecologic and non-gynecologic tumors. It drew on the published literature and illustrative cases from the authors' department at the University of Pittsburgh Medical Center.
• Exposure: Asbestos was not studied. The review mentioned it once, stating that diffuse peritoneal mesothelioma occurs typically from secondary exposure to asbestos. No fiber type, product, job or dose was given.
• Main results:
  • The review stated that diffuse peritoneal mesothelioma accounts for 10-20% of all mesotheliomas and is less common than primary peritoneal serous carcinoma.
  • The review stated that malignant mesothelioma has a poor prognosis, with an average survival of less than 2 years.
  • The authors noted that the diagnosis of mesothelioma potentially has medical-legal implications.
  • The authors wrote that, without supportive clinical or radiological correlation and proper ancillary testing, it is often preferable to diagnose "atypical mesothelial proliferation" and recommend a tissue biopsy. They gave the reasons as the tumor's rarity, its variable appearance, and the inability to assess tissue invasion in washings.
  • The review described the expected staining pattern of mesothelioma cells. They should not stain with BerEp4, B72.3 or MOC31, and should stain for calretinin, CK5/6, D2-40 and WT1.
  • Citing an earlier study, the review stated that a homozygous deletion of the CDKN2A (p16) gene on chromosome 9p21, detected by fluorescence in situ hybridization, appears to show the most promising results as a marker for malignancy in mesothelial proliferations. The review said this abnormality is seen in over 70% of mesotheliomas, and that these cases typically have a worse prognosis.
  • The review described two mesothelial lesions that are distinct from malignant mesothelioma. Multilocular peritoneal inclusion cyst, formerly called multicystic mesothelioma, is benign. Well differentiated papillary mesothelioma is a tumor of uncertain malignant potential.
  • The review stated that non-cancerous findings such as endometriosis, endosalpingiosis and reactive mesothelial proliferations can be misinterpreted as malignancy in washings.
  • The review stated that positive washings are no longer used for staging endometrial cancer and are not included in staging cervical carcinoma.
• The authors' conclusion: The authors concluded that washing cytology should be correlated with the surgical pathology of the resected tumor in all cases. They also concluded that cytopathologists must be prepared for a wide variety of appearances and be aware of differential diagnoses and pitfalls.

Topics

Medical terms in this study, explained in our Lexicon: Neoplasm, Staging, Ovarian Cancer, Carcinoma, Reactive Mesothelial Hyperplasia, Mesothelioma, Fluorescence In Situ Hybridization (FISH).

Related studies

• Peritoneal washing cytology findings of disseminated myxoid leiomyosarcoma of uterus: report of a case with emphasis on possible differential diagnosis — W.K. Ng, P.C. Lui, et al. (2002)
• Lectin binding properties of cells from serous effusion and peritoneal washing specimens — P.W. Shield (1989)
• Biological effects of chrysolite after SO2 sorption. iii. effects on the biochemical components of alveolar washing — A. Oblin, J.M. Warnet, et al. (1978)
• Comprehensive genomic analysis of malignant pleural mesothelioma identifies recurrent mutations, gene fusions and splicing alterations — R. Bueno, E.W. Stawiski, et al. (2016)
• The distribution of vimentin and keratin in epithelial and nonepithelial neoplasms. A comprehensive immunohistochemical study on formalin- and alcohol-fixed tumors — N. Azumi, H. Battifora (1987)
• Comprehensive review of BAP1 tumor predisposition syndrome with report of two new cases — K. Rai, R. Pilarski, et al. (2016)

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