Table of Contents
Definition / general | Clinical features | Sites | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Electron microscopy description | Differential diagnosis | Additional referencesCite this page: Arora K. Angiomyofibroblastoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/softtissueangiomyofibroblastoma.html. Accessed February 8th, 2023.
Definition / general
- Benign, well-circumscribed myofibroblastic tumor, usually in vulva
- May overlap with cellular angiofibroma
- First described in 1992 (Am J Surg Pathol 1992;16:373)
Clinical features
- Uncommon slow growing painless mass, usually females of reproductive age
Sites
- Usually vulvar, 10 - 15% in vagina
- Also scrotum or paratesticular soft tissue in men (median age 57 years)
Case reports
- 27 year old man with angiomyofibroblastoma of the male inguinal region (Arch Pathol Lab Med 2000;124:1679)
- 48 year old woman with angiomyofibroblastoma of the vulva (Acta Med Okayama 2006;60:237)
- 80 year old woman with angiomyofibroblastoma of the vulva with sarcomatous transformation (Am J Surg Pathol 1997;21:1104)
- Recurrent angiomyofibroblastoma of the vagina (Eur J Gynaecol Oncol 2007;28:324)
Treatment
- Excision, only rarely recurs, does not metastasize
Gross description
- Well circumscribed but not encapsulated, usually 5 - 7 cm or less, tan-pink soft cut surface, no necrosis
Microscopic (histologic) description
- Thin fibrous pseudocapsule, alternating hyper- and hypocellular areas with prominent thin walled and ectatic vessel in edematous stroma (Mod Pathol 1996;9:284)
- Round to spindled tumor cells have eosinophilic cytoplasm and often bi- or multi-nucleation
- May have plasmacytoid or epithelioid morphology, or rarely show degenerative changes
- Tumor cells are concentrated around vessels
- Mast cells common
- 10% have mature adipose tissue
- No / rare mitotic figures, no / rare red blood cell extravasation, no atypia
- Most menopausal patients have less cellularity, less edema but more fibrosis and vessel wall hyalinization
Microscopic (histologic) images
Positive stains
- Vimentin, desmin (strong and diffuse, may be reduced in post-menopausal patients), ER, PR, smooth muscle actin or pan-muscle actin (focal, Hum Pathol 1997;28:1046), occasional CD34
Electron microscopy description
- Myofibroblastic and fibroblastic features
Differential diagnosis
- Aggressive angiomyxoma: not circumscribed, > 5 cm, less cellular, less vascular but vessels are large and thick walled, stromal mucin and RBC extravasation are present, infrequent plump stromal cells, usually actin negative
- Cellular angiofibroma: more cellular uniformly, perivascular hyalinization and large, thick walled vessels, usually actin/desmin negative
- Epithelioid leiomyoma: more cellular, no biphasic pattern, usually no binucleation, no / rare mast cells
Additional references