Lung
Mesenchymal tumors
Multiple pulmonary leiomyomatous hamartomas
Author: Roseann I. Wu, M.D., M.P.H.
Last author update: 1 August 2016
Last staff update: 7 June 2023
Copyright: 2002-2024, PathologyOutlines.com, Inc.
PubMed Search: Multiple pulmonary leiomyomatous hamartomas
Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Sites | Etiology | Clinical features | Diagnosis | Radiology description | Prognostic factors | Case reports | Treatment | Gross description | Microscopic (histologic) description | Positive stains | Negative stains | Differential diagnosisCite this page: Wu R. Multiple pulmonary leiomyomatous hamartomas. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lungtumorleiomyomatoushamartomas.html. Accessed December 25th, 2024.
Definition / general
- Proliferation of multiple smooth muscle nodules in the lung parenchyma
Essential features
- Multiple, small, unencapsulated nodules of smooth muscle in fascicles
- Extremely rare, with controversial relationship to benign metastasizing leiomyoma or leiomyosarcoma
Terminology
- Controversial whether are true hamartomas or represent metastasizing leiomyoma or leiomyosarcoma
Epidemiology
- Extremely rare, almost always asymptomatic middle aged women
Sites
- Throughout lung parenchyma, occasionally bronchovascular distribution
Etiology
- Possible origin from contractile system of the lung acini (contractile interstitial cell)
Clinical features
- Usually incidental
Diagnosis
- Biopsy of nodules
Radiology description
- Xray: abnormal nodular shadows
- CT: multiple small pulmonary nodules
Prognostic factors
- Potential clonal expansion in long term follow-up (Pathol Int 2009;59:828)
Case reports
- 31 year old woman whose tumors had secondary ossification (Pathol Int 1999;49:222)
- 46 year old man associated with bronchogenic cyst (Arch Pathol Lab Med 2003;127:e194)
Treatment
- Surveillance, enucleation or surgical removal
Gross description
- 2 - 15 mm white, firm, solid, well demarcated nodules
Microscopic (histologic) description
- Excessive smooth muscle bundles in fascicles, not associated with tumor
- Spindle cells with eosinophilic, fibrillary cytoplasm and blunt, elongated nuclei
- Scattered glands and duct-like spaces may be seen
- No mitoses, no nuclear atypia
Differential diagnosis
- Benign metastasizing leiomyoma
- Lymphangioleiomyomatosis
- Native pulmonary muscle proliferation
