Multifocal micronodular pneumocyte hyperplasia (MMPH) is a subtype of
pneumocytic hyperplasia Pneumocytic hyperplasia is an hyperplasia of pneumocytes lining pulmonary alveoli
A pulmonary alveolus (plural: alveoli, from Latin ''alveolus'', "little cavity"), also known as an air sac or air space, is one of millions of hollow, distensible ...
(hyperplasia of
pneumocyte
A pulmonary alveolus (plural: alveoli, from Latin ''alveolus'', "little cavity"), also known as an air sac or air space, is one of millions of hollow, distensible cup-shaped cavities in the lungs where oxygen is exchanged for carbon dioxide. Al ...
s lining
pulmonary alveoli
A pulmonary alveolus (plural: alveoli, from Latin ''alveolus'', "little cavity"), also known as an air sac or air space, is one of millions of hollow, distensible cup-shaped cavities in the lungs where oxygen is exchanged for carbon dioxide. Al ...
).
Several synonymous terms have been done for this entity: adenomatoid proliferation of alveolar epithelium, papillary alveolar hamartoma, multifocal alveolar hyperplasia, multinodular pneumocyte hyperplasia.
These multifocal lesions are observed in
tuberous sclerosis
Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that causes non-cancerous tumours to grow in the brain and on other vital organs such as the kidneys, heart, liver, eyes, lungs and skin. A combinatio ...
, and can be associated with
lymphangioleiomyomatosis and
perivascular epithelioid cell tumour (PEComa or clear cell "
sugar tumor
Perivascular epithelioid cell tumour, also known as PEComa or PEC tumour, is a family of mesenchymal tumours consisting of perivascular epithelioid cells (PECs). These are rare tumours that can occur in any part of the human body.
The cell type ...
")).
It can be diagnosed through
lung biopsy using
thoracoscopy.
Microscopy
* Well-demarcated, nodular lesions ranging 2–5 mm in pulmonary parenchyma.
* Type II pneumocytes without nuclear atypia lined thickened alveolar septa and proliferated papillary structures.
* Enlarged cuboidal cells lining mildly thickened alveolar septa.
* Enlarged cuboidal cells have abundant, eosinophilic cytoplasm and large, round nuclei.
* Papillary pattern with irregular margin and lymphocyte infiltration in the stroma.
* No proliferation of immature smooth muscle cells suggestive of
lymphangioleiomyomatosis.
See also
*
atypical adenomatous hyperplasia
*
pneumocytic hyperplasia Pneumocytic hyperplasia is an hyperplasia of pneumocytes lining pulmonary alveoli
A pulmonary alveolus (plural: alveoli, from Latin ''alveolus'', "little cavity"), also known as an air sac or air space, is one of millions of hollow, distensible ...
References
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External links
Microscopical imagesMicroscopical imagesMicroscopical images
Pulmonary lesion