Angiomyofibroblastomas are benign mesenchymal neoplasms usually found in the pelvis or perineum especially the vulva.
Angiomyofibroblastomas are uncommon tumors predominantly found in adult women usually between menarche and menopause. Approximately 10% of these tumors have been described in postmenopausal women. In men, they are rare 1.
The usual complaint is a slowly progressive well-defined painless mass 1.
Angiomyofibroblastomas are well-circumscribed myofibroblastic lesions characterized by prominent stromal vessels surrounded by round to ovoid or spindle-shaped tumor cells 1-4.
The etiology of angiomyofibroblastoma is unknown 1.
Most angiomyofibroblastomas are found in the perineal region with most being located in the vulva or perineum followed by the vagina and uterine cervix. They can occur in other regions for example in the mediastinum or nasal cavity but only in very rare occasions 1-4.
Macroscopically angiomyofibroblastomas are well-demarcated lesions, they are not encapsulated and some might be pedunculated. They usually have a soft consistency and are of pink-tan color 1.
The histological appearance of angiomyofibroblastomas is characterized by the following features 1-4:
- thin fibrous pseudocapsule
- prominent thin-walled ectatic vessels in an edematous matrix
- round to ovoid epithelioid or spindle-shaped tumor cells with eosinophilic cytoplasm
- well-differentiated adipocytic components in about 10% of cases
- degenerative nuclear atypia
- rarely morphological overlap with aggressive angiomyxoma
Immunohistochemistry stains express vimentin and are usually positive for desmin, unless in postmenopausal women. There is only a focal expression of smooth muscle actin (SMA) and muscle-specific actin (MSA). In addition tumor cells usually express estrogen receptor, progesterone receptor and occasionally CD34 1.
Angiomyofibroblastomas are usually solid well-demarcated vascularized lesions.
There is some variability with respect to ultrasound findings. On one hand, angiomyofibroblastomas have been described as solid-cystic-appearing lesions with inhomogeneous echogenicity on the other hand homogeneous appearing lesions have also been described. Color Doppler imaging usually displays intralesional or peripheral vascularization 2-4.
Angiomyofibroblastomas apparently appear as solid well-circumscribed variably heterogeneous soft tissue masses 2-4.
- T1: low to intermediate signal intensity
- T2: heterogeneous mixed to high signal intensity
- T1 C+ (Gd): intense enhancement with variable heterogenicity
The radiological report should include a description of the following:
- location and size of the tumor
- relation to other organs
- relation to soft tissue structures structures
Treatment and prognosis
The main treatment is surgical excision. Angiomyofibroblastomas are benign and have an excellent prognosis with local recurrences being reportedly rare even with marginal excision 1,2,6.
History and etymology
Angiomyofibroblastoma was initially described by Fletcher and colleagues in 1992 2-5,8.
Conditions with similar clinical presentation or appearance of angiomyofibroblastomas include 1-4:
- 1. W.H.O. Classification WHO Classification of Tumours Editorial Board, Who Classification of Tumours Editorial. Soft Tissue and Bone Tumours. (2020) ISBN: 9789283245025
- 2. Wolf B, Horn LC, Handzel R, Einenkel J. Ultrasound plays a key role in imaging and management of genital angiomyofibroblastoma: a case report. (2015) Journal of medical case reports. 9: 248. doi:10.1186/s13256-015-0715-4 - Pubmed
- 3. Shoji T, Takeshita R, Mukaida R, Sato T, Taguchi M, Sasou S. Angiomyofibroblastoma of the vulva diagnosed preoperatively: A case report. (2017) Molecular and clinical oncology. 7 (3): 407-411. doi:10.3892/mco.2017.1347 - Pubmed
- 4. Eckhardt S, Rolston R, Palmer S, Ozel B. Vaginal Angiomyofibroblastoma: A Case Report and Review of Diagnostic Imaging. (2018) Case reports in obstetrics and gynecology. 2018: 7397121. doi:10.1155/2018/7397121 - Pubmed
- 5. Lim KJ, Moon JH, Yoon DY, Cha JH, Lee IJ, Min SJ. Angiomyofibroblastoma arising from the posterior perivesical space: a case report with MR findings. (2008) Korean journal of radiology. 9 (4): 382-5. doi:10.3348/kjr.2008.9.4.382 - Pubmed
- 6. Qiu P, Wang Z, Li Y, Cui G. Giant pelvic angiomyofibroblastoma: case report and literature review. (2014) Diagnostic pathology. 9: 106. doi:10.1186/1746-1596-9-106 - Pubmed
- 7. Fletcher CD, Tsang WY, Fisher C, Lee KC, Chan JK. Angiomyofibroblastoma of the vulva. A benign neoplasm distinct from aggressive angiomyxoma. (1992) The American journal of surgical pathology. 16 (4): 373-82. doi:10.1097/00000478-199204000-00006 - Pubmed