Vagina
Malignant tumors
Aggressive angiomyxoma

Author: Shweta Gera, M.D. (see Authors page)
Editor: Arzu Buyuk, M.D.

Revised: 26 September 2017, last major update March 2014

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Aggressive angiomyxoma vagina

See also: Vulva topic
Cite this page: Gera, S. Aggressive angiomyxoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/vaginaaggressiveangiomyx.html. Accessed November 22nd, 2017.
Definition / general
  • Rare, locally aggressive, infiltrative mesenchymal tumor of unknown etiology
  • Most commonly affecting perineum and pelvic soft tissues in women of reproductive age
  • Also rarely seen in men and children (see penis / scrotum and testis / spermatic cord chapters)
  • Slow growing, bland appearing myxoid tumor with a tendency to recur
  • Called "aggressive" due to neoplastic nature of blood vessels, locally infiltrative behavior and high risk of local recurrence; however, does not have frank malignant behavior (Am J Surg Pathol 1983;7:463)
Terminology
  • Also called deep angiomyxoma
  • First described in 1983 as aggressive angiomyxoma of the female pelvis and perineum (Am J Surg Pathol 1983;7:463)
Epidemiology
Sites
Pathophysiology
Etiology
  • Classified as "tumors of uncertain differentiation" in WHO classification
Clinical features
Diagnosis
  • Mainly based on histological features (vascularized myxoid lesion with bland spindle and stellate stromal cells)
  • Cytology is not diagnostic although it does help in offering differential diagnosis of a myxoid mesenchymal neoplasm
  • Often misdiagnosed clinically and mistaken for more common entities
Radiology description
  • Preoperative imaging (CT, MRI) is important to estimate true size of tumor as it has infiltrative margins
  • Sonography: hypoechoic or appears as a frankly cystic mass
  • CT scan: well defined margin, iso or hypoattenuation compared to muscles
  • MRI: imaging study of choice - "swirled pattern"
  • Angiography: generally hypervascular mass (Rev Bras Ginecol Obstet 2013;35:575)
Radiology images

Images hosted on other servers:

MRI showing a mass

Prognostic factors
Case reports
Treatment
  • Wide local excision with tumor free margins (to reduce high recurrence rate)
    • Difficult due to infiltrative nature of tumor at margins
    • Does not totally prevent local recurrence (Gynecol Oncol 1991;42:79)
  • Incomplete or partial resection is acceptable in patients with high operative morbidity and young patients where preservation of fertility is a concern
  • Gonadotropin releasing hormone (GnRH) agonist: primary treatment of small tumors, as adjuvant therapy for residual tumor and in the treatment of recurrence
    • Disadvantages: causes menopausal symptoms and bone loss; tumor may become resistant to therapy; therapy withdrawal may cause tumor regrowth
  • Radiotherapy or chemotherapy: unlikely to be a useful adjunct to primary surgery
  • Embolization or chemoembolization: not suitable (Rev Bras Ginecol Obstet 2013;35:575)
  • Close longterm followup (regardless of the primary treatment) to assess for recurrence (Rev Bras Ginecol Obstet 2013;35:575, J Obstet Gynaecol 2005;25:622)
Gross description
Microscopic (histologic) description
  • Spindled and stellate cells in hypocellular myxomatous stroma, no / rare mitotic figures, no atypia
  • Numerous stromal blood vessels of varying calibre, ranging from thin walled capillary-like vessels to large vessels with thick muscular walls (Histopathology 2009;54:156)
  • Also thick walled vessels with dilated lumina and occasional hyaline thickening of adventitia
  • Perivascular smooth muscle fibers radiating from thick walled blood vessels are a characteristic feature (Histopathology 2009;54:156, Hum Pathol 1985;16:621)
  • Stromal mast cells and extravasated erythrocytes are common
  • Unusual features include foci of increased cellularity and more fibrous stroma, the latter is associated with recurrent tumors (Histopathology 2009;54:156)
  • No bizarre stromal cells
Microscopic (histologic) images

Images hosted on other servers:

Hypocellular tumor composed of bland spindle cells

Round or oval nuclei

Hypocellular, poorly circumscribed

Figures 1 & 2

Cytology description
  • No specific features, biopsy / excision required for diagnosis (Diagn Cytopathol 1997;16:425)
  • Cytology similar to aggressive angiomyxoma of other sites like vulva, pelvis, perineum: low cellularity, monomorphic ovoid cells suggestive of spindle cell tumor
  • Mucoid or myxoid background associated with a prominent number of red blood cells, stellate or fusiform cells with delicate elongated cytoplasmic extensions with bland nuclei with a fine chromatin pattern
  • Nuclear membranes are smooth and uniform
  • Nucleoli and chromocenters inconspicuous or usually not seen
  • Usually no necrosis or mitosis (Diagn Cytopathol 1997;16:425)
Positive stains
Electron microscopy description
  • Primitive mesenchymal cells with fibroblastic features
  • Admixture of Schwann cells and fibroblasts is seen
  • Schwann ceils display branching cytoplasmic processes, a continuous basal lamina, mesoaxon-like formations and intracytoplasmic bundles of 25 nm microtubules (Hum Pathol 1985;16:621)
Molecular / cytogenetics description