Corpora amylacea in mesothelioma of the atrioventricular node

Our plain-English summary of Corpora amylacea in mesothelioma of the atrioventricular node, by R. David, Y. Hiss (The Journal of Pathology, 1978).

The study

• Authors: R. David, Y. Hiss
• Journal: The Journal of Pathology
• Published: 1978;124(2):111-6
• Type of article: Case report
• Cited by: 9 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Rounded or polyhedral, acellular, dense lamellated structures were seen within gland-like spaces in a case of atrioventricular mesothelioma. These structures exhibited many of the histochemical characteristics of amyloid, viz., pink colour with green birefringence and bright red fluorescence with alkaline Congo red; ortochromasia and red birefringence with standardised toluidine blue; positive DMAB-nitrite and diazotisation coupling reactions and spontaneous autofluorescence. It is suggested that these bodies are derived from spontaneous assembly or polymerisation of microfibrils of desquamated cells lining the cystic spaces of the tumour as occurs in prostatic corpora amylacea. The peculiar intramyofibre proliferation of tumour cells in the peripheral part of the tumour suggests that viable tumour cells can penetrate, survive and proliferate within atrial or nodal myofibres leaving an intact sarcolemmal sheath. The slow tumour cell growth and the successive degeneration of central tumour cells may explain the tubular and/or glandular pattern constantly seen in this tumour.

In plain English

This was a case report from Sheba Medical Center and Tel-Aviv University in Israel. It described a tumour the authors call mesothelioma of the atrioventricular (AV) node, a rare lesion in the heart's conduction system. The article did not mention asbestos or any other exposure. The patient was a 66-year-old retired clerk with high blood pressure whose ECG had shown first degree AV block one year before death. He was admitted with nausea, severe headache and vomiting, developed complete AV block, and died in hospital. Autopsy confirmed an extensive subarachnoid haemorrhage. It also found a 1.5 cm mass in the wall between the upper heart chambers that had replaced most of the AV node. Under the microscope, about 40 per cent of the tumour's cysts and tubules contained dense bodies resembling prostatic corpora amylacea. About 10 per cent of these bodies showed the green birefringence of amyloid with Congo red stains. Tumour cells were also seen growing inside single heart muscle fibres. The authors suggested the bodies form from microfibrils of shed tumour cells, as happens in the prostate.

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: case report (single autopsy case with histochemical staining study)
• Who was studied: one 66-year-old man, a retired clerk, seen at Sheba Medical Center, Israel; date of the case not stated
• Main results:
  • The patient developed complete AV block in hospital, after an ECG one year before death had shown first degree AV block
  • Autopsy confirmed an extensive subarachnoid haemorrhage
  • A 1.5 cm mass was found in the lower interatrial septum just above the atrioventricular ring
  • The mass had no capsule and replaced most of the AV node
  • About 40 per cent of the tumour's cysts and tubules contained amorphous structures similar to prostatic corpora amylacea
  • About 10 per cent of these structures showed the typical green birefringence of amyloid when stained with Congo red and viewed under crossed polars
  • All of these bodies appeared bright red on fluorescence microscopy with alkaline Congo red, whether or not they showed green birefringence
  • At the edge of the tumour, extra nuclei were found inside single atrial muscle fibres, enclosed by the fibre's membrane (sarcolemma)
• The authors' conclusion: The authors suggested that the bodies are formed by spontaneous assembly or polymerisation of microfibrils from shed cells lining the tumour's cystic spaces, as occurs in prostatic corpora amylacea. They also suggested that tumour cells can penetrate, survive and multiply inside atrial or nodal muscle fibres.
• Limitations the authors state:
  • In comparing this tumour with similar heart tumours in a strain of rats, the authors noted they cannot be sure the rat tumours have the same origin as the human tumour

Topics

The National Library of Medicine indexes this study under subjects our site covers: Mesothelioma.

Medical terms in this study, explained in our Lexicon: Mesothelioma, birefringence.

Related studies

• Congenital polycystic tumor of the atrioventricular node (endodermal heterotopia, mesothelioma): a histogenetic appraisal with evidence for its endodermal origin — G. Fine, U. Raju (1987)
• Mesothelioma of the atrioventricular node — K. Nishida, G. Kamijima, et al. (1985)
• "Mesothelioma of the atrioventricular node" with long-standing complete heart block. Report of a case — I.R. Wanless, B.W. Mielke, et al. (1975)
• Mesothelioma of the atrioventricular node and congenital complete heart block — R. Subramanian, B. Flygenring (1989)
• Primary mesothelioma of atrioventricular node: cause of sudden death — E.H. Hemsted (1986)
• Synovial sarcoma of the heart arising from a so-called mesothelioma of the atrio-ventricular node — E.A. Sheffield, B. Corrin, et al. (1988)

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