Aggressive Angiomyxoma of the Vulva in a Woman

AAM: aggressiveangiomyxoma

ER: Estrogen Receptor

HE: Hematoxylin and Eosin

SMA: Smooth Muscle Actin

CA: Cancer Antigen

CEA: Carcino-Embryonic Antigen

AFP: α-Fetoprotein

SCC: Squamouscell Carcinomas

First reported in 1983, aggressive angiomyxoma is a rare and slow growing mesenchymal tumour [1]. AAM usually has no clinical symptom and grows in a insidious manner as well as possesses a moderate-to-high risk of local relapse. Its diagnosis is still difficult because of its non-specific clinical and radiological aspects. It has poor long-term prognosis. AAM could appear in vulva, perineal region, buttocks, or pelvis in women at reproductive age [2,3]. So far, the underlying causes for AAM remain unclear. A few of recent studies suggest that AAM may be associated with chromosome alteration in 12q13-15 region [4,5]. Here, we describe a case of a giant vulvar AAM and take the treatment procedure for the patient, together with a literature review on AAM.

We present the case of a 42-year-old female patient with a giant solid mass on the right vulva for 1 year, with no specific past medical history noted and has never been pregnant. No treatment was given because she did not pay any attention to it at the beginning. The mass grows and increases quickly, without fever, redness, secreta, dysmenorrhea, burning sensation, bleeding, abdominal pain, perineum pain, dysuria, difficulty in defecation, or other symptoms. Her complaints were merely of discomfort when seated and a discharge with a fishy odor. She denied having had oral, anal or vaginal intercourse when questioned privately. She had no history of surgery, inflammatory disease, medications, or trauma and her family history was unremarkable. The mass was round, well-circumscribed, pedunculated, soft, spongy in consistency and nontender. The size of the mass was about16cm-10cm with a pedicle of 3cm (Figure 1). 

 Figure 1: A mass in the perineum (arrows). The size of the mass was about 16cm-10cm with a pedicle of 3cm. 

No enlarged inguinal lymph nodes were palpated bilaterally. Bimanual examination revealed that no nodule appeared on vaginal, cervix, uterus, or bilateral accessory. Surface body ultrasound showed that several vessels were observed in the perineum of the mass with a sign of slight blood flow signal. In her pelvic and abdominal cavity, no abnormality was found in enhanced magnetic resonance imaging (Figure 2). 

Figure 2: MRI of the pelvis showing the perineal mass (white arrow). 

The laboratory white blood cell, alanine amino transferase and C-reactive protein levels data revealed no significant abnormalities. The tumor markers, including cancer antigens Cancer Antigen (CA)-125, CA-199, Carcino-Embryonic Antigen (CEA), CA-153, α-Fetoprotein (AFP) and Squamous Cell Carcinomas (SCC), were all in Fig normal ranges. We present a total excision of a tumor mass with clear margins at the second Affliated Hospital, Zhejiang university school of medicine, with no evidence of any relapse to date during the follow-up (Figure 3). 

Figure 3: Reposition of mucosal flap and suture an incision site after tumor removal. 

The histopathologic examination of the resected mass confirmed the diagnosis of AAM (Figure 4). The patient was discharged 12 days after a surgery with satisfactory outcomes. No evidence of recurrence or distant metastasis was observed during the 24-month follow-up period. 

Figure 4: The pathologic and immunohistochemical characteristics of the mass. (A) Desmin was positive for immunohistochemistry. Magnification × 200. (B) Strong and diffuse positivity for Estrogen Receptors (ER) (IHC for ER, ×200). (C) HE staining; magnification, ×100. (D) HE staining; magnification, ×200.Small to medium-sized parenchyma vessels and more thick-walled small vessels. (E) Strong nuclear positivity in PR (×200). (F) S-100 stain was positive.

The AAM mainly occurs on the vulva, vagina, pelvic cavity, hips, perineum, and crissum in reproductive female aging from 30 to 40 years old. Occasionally, AAM occurs in men. The morbidity rate of men versus women is about 1:6. It is aggressive because of its nature with local infiltration and recurrence. Its relapse rate varies from 35% to 72%. The AAM primely occurs in the perineal and pelvic regions, which may lead to a possible misdiagnosis as Bartholin gland cyst or hernia. In addition, AAM is also difficult to differentiate from angiomyofibroblastoma due to similar morphology. Therefore, to diagnose AAM needs the evidence of clinical features and histologic pathologies. 

AAM is described as having both smooth and adherent margins that infiltrate the host’s tissues. The histopathological characteristics consist of a population of hypocellular spindle cells sparsely spread in a loose myxoid matrix with collagen bundles. In conclusion, AAM is a locally benign and aggressive mesenchymal entity, and the surgical removal of the mass can cure it.

None.

The data used and/or analysed during the current study are available from the corresponding author on reasonable request.

This study was approved by the ethics committee of the 2^nd Affiliated Hospital, Zhejiang University School of Medicine (Hangzhou, People’s Republic of China) and was permitted to be published. Written informed consent to have the case details and accompanying images published was obtained from the patient and her husband. All clinical investigations were conducted in accordance with the principles expressed in the Declaration of Helsinki.

Written informed consent was obtained from the patients for the publication of this case report and any accompanying images. A copy of the consent form is available for review by the Editor of this journal.

The authors declare that they have no competing interests.