Cardiac Path Online
Pathology of Purkinje Cell Tumours
Purkinje Cell Tumor of uncertain nature, seen only in young infants and is characterized clinically by severe and often fatal arrhythmias.
Present knowledge of these lesions consider them as a form of “cardiac hamartoma”.
This lesion is not a tumour of Purkinje cell but a cardiomyopathy of unknown etiology and pathogenesis, the possible suggestions are:
- Persistence of early developmental stage of myocytes with their change into oncocytes.
Viral infection as rubella, in early stage of gestation may be a possible cause.
- With advances of electrophysiologic mapping, attention is drawn to the increasing incidence of ventricular tachycardia in infants and its relevance to Purkinje cell tumours.
Gross features: These are circumscribed or diffuse lesions, yellowish-white in color, and usually in the subendocardial or subepicardial location.
They usually involve ventricles but atrial myocardium may also be involved.
The appearance is distinctive, showing clusters or sheaths of swollen myocardial cells (twice the normal size) with granular eosinophilic, often vacuolated cytoplasm.
Mitotic figures are absent.
Note: Histiocytoid cardiomyopathy is considered to be the result of hamartoma-like aggregations of cardiac myocytes with features similar to those of oncocytes.
This syndrome is likely caused by prenatal myocardial or systemic (viral) injury.
It has been reported in a study that there is a high prevalence of anomalies involving the nervous system and eyes and of oncocytic cells in various glands.
Evidence is presented to exclude the possibilities that the disorder represents a developmental anomaly of the atrioventricular conduction system, a multifocal tumour of Purkinje cells, a developmental arrest of cardiac myocytes, and a diffuse type of mitochondrial cardiomyopathy.
The close association of the lesion with cardiac arrhythmias in very young infants is of special interest to pathologists.
Histiocytoid cardiomyopathy is a cause of sudden death in infancy.
Surgical excision of nodules of histiocytoid cells can result in clinical remission.
Photographs: Image1 ; Image2 ; Image3 ; Image4 (Multifocal cardiac Purkinje cell tumor in infancy.)
Benign tumors of cardiac myocytes. In Rosai J and Sobin LH (Eds.). Tumors of the heart and great vessels. Atlas of tumor pathology of Armed Forces Institute, 3rd series, fascicle 16 1996; Washington, DC pp. 55–67.
Multifocal Purkinje-like tumor of the heart. Occurrence with other anatomic abnormalities in the atrio-ventricular junction of an infant with junctional tachycardia, Lown–Ganong–Levine syndrome, and sudden death.
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