Pulmonary microcystic fibromyxoma

Definition

A rare primary myxoid tumour of the lung with a distinctive microcystic architecture.

Epidemiology

These tumours occur in adults.

Clinical features

Asymptomatic, detected radiologically

Macroscopic appearances

The tumours are peripheral and well circumscribed.

Histopathology

The tumour is composed of bland spindle or stellate cells within a fibromyxoid stroma. Microcystic spaces are up to 200 mm in diameter.

Immunohistochemistry

	Vimentin	3/31
	AE1/AE3	0/31
	EMA	0/31
	Cam 5.2	0/31
	Calretinin	0/31
	S-100	0/31
	HMB-45	0/31
	TTF-1	0/31
	CD31	0/31
	CD34	0/31
	SMA	0/31
	HHF35	0/31
	Desmin	0/31
	GFAP	0/31

Ultrastructure

Differential diagnosis

Myxoid pulmonary hamartoma
Pulmonary alveolar adenoma
Salivary gland type mixed tumour
Metastatic sarcoma
- extraskeletal myxoid chondrosarcoma
- low-grade fibromyxoid sarcoma
- low-grade myxofibrosarcoma

Management

Local resection

Prognosis

Benign

References

1 Shilo K, Miettinen M, Travis WD, et al. Pulmonary microcystic fibromyxoma: Report of 3 cases. Am J Surg Pathol 2006; 30:1432-5

This page last revised 29.11.2006.

©SMUHT/PW Bishop