Teaching Case

An 80-year-old woman presented with pruritus and burning sensation with micturition for 6 months. Physical examination revealed a lesion in the vulva, with clitoris and vagina invasion and a palpable right inguinofemoral node. Biopsy revealed human papillomavirus (HPV)-associated invasive squamous cell carcinoma in the vulvar lesion and right inguinofemoral node.

Pelvic magnetic resonance imaging (MRI) depicted the vulvar carcinoma measuring 11 cm in the longest axis with intermediate signal on T2-weighted imaging (WI), restricted diffusion on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) map and early contrast enhancement on dynamic contrast-enhanced (DCE) imaging. The tumour invaded both vagina and urethra up to their upper thirds. The anus was not involved.

Additionally, the large pathological right inguinal lymph node was shown. There were also small right external iliac and bilateral surgical obturator lymph nodes.

These findings are diagnostic of the International Federation of Gynaecology and Obstetrics (FIGO) stage III vulvar cancer [1].

Background

Carcinoma of the vulva is a rare tumour, that primarily affects post-menopausal women [2].

The commonest histological type is squamous cell carcinoma. Risk factors include older age, chronic vulvar dermatosis, HPV infection and vulvar intraepithelial neoplasia [1, 3].

Clinical Perspective

Most cases of vulvar cancer are symptomatic, presenting as painful lesion, pruritus, abnormal bleeding or discharge, and a lump or ulcer [2, 4]. Diagnosis is made by physical examination and biopsy [5]. Imaging role is to assess locally advanced and distal disease [3]. MRI is indicated in larger tumours, being the best imaging technique for local staging [2, 5].

Imaging Perspective

The MRI protocol recommended by the European Society of Urogenital Radiology (ESUR) to stage vulvar carcinoma includes axial T1WI, axial and sagittal T2WI, axial DWI and axial DCE imaging of the pelvis, and axial T2WI and DWI from the renal hila to the inguinal region [5].

On MRI, vulvar carcinoma appears as a T1WI low signal intensity and T2WI moderate-to-high signal solid mass with early contrast enhancement on DCE imaging. Similarly to other high cellularity tumours, the mass restricts at DWI [3].

Local invasion is best depicted at DWI and DCE imaging. Loss of the target appearance of the urethra and interruption of the low-T2-signal of the vaginal wall and/or anal sphincter by tumour are suggestive of invasion [3].

A lymph node is considered high risk for metastasis when its short axis is >1 cm. Other suspicious features include irregular contour, round shape, necrosis and loss of fatty hilum [5].

Outcome

In advanced stages, vulvar cancer treatment modalities may include surgery, radiotherapy and chemotherapy. The best approach should be discussed in a multidisciplinary setting [4, 5].

Patients with positive regional lymph nodes or with tumour extension to the upper part of adjacent perineal structures or with disease fixed to the pelvic bone are usually treated with external beam radiation therapy with concurrent chemotherapy [2, 4].

Take Home Message / Teaching Points

MRI has an important role in staging locally advanced vulvar cancer and establishing treatment planning.

Written informed patient consent for publication has been obtained.