What are the steps to diagnose vulvar cancer?

Diagnosis of Vulvar Cancer

The diagnosis of vulvar cancer requires careful clinical examination of suspicious lesions followed by punch biopsy with pathologic review as the definitive diagnostic step. 1

Initial Evaluation

Clinical Presentation

• Most common symptoms:
  • Pruritus (itching) - most frequent and long-lasting symptom
  • Pain or irritation
  • Visible mass, lump, or ulcer
  • Vulvar bleeding or discharge
  • Some cases may be asymptomatic 1, 2

Physical Examination

• Thorough inspection of the entire vulva:
  • Most vulvar cancers (90%) are squamous cell carcinomas 1
  • Most commonly located in the labia majora, but can also affect labia minora, clitoris, mons, or perineum 1
  • Document lesion characteristics:
    • Size
    • Location relative to midline
    • Relationship to adjacent organs (urethra, vagina, anus)
    • Presence of multifocal disease 1
  • Clinical palpation of groin lymph nodes (though this has high false-negative rate) 1

Diagnostic Procedures

Biopsy

• Punch biopsy is the gold standard for diagnosis 1
  • Must include underlying stroma
  • Avoid necrotic areas
  • All suspicious vulvar lesions should be biopsied 1
  • Provides definitive histopathologic diagnosis

Additional Diagnostic Workup

After biopsy confirms vulvar cancer:

1. Laboratory tests:

   • Complete blood count (CBC)
   • Liver and renal function tests
   • HPV testing (up to 69% of vulvar cancers are attributed to HPV infection, particularly high-risk strains HPV-16 and HPV-18) 1

2. Examination of related structures:

   • Evaluation of vagina and cervix including cytologic smears (due to multifocal nature of squamous cell intraepithelial neoplasia) 1
   • Examination under anesthesia with cystoscopy or proctoscopy if indicated 1

3. Imaging studies (particularly for tumors ≥2cm):

   • CT of abdomen and pelvis
   • MRI of pelvis (can help delineate extent of tumor and relationship to adjacent structures)
   • PET/CT may be used for treatment planning or to detect metastases 1, 3

Staging Process

Vulvar cancer is surgically staged using either:

• FIGO (International Federation of Gynecology and Obstetrics) system
• AJCC TNM (American Joint Committee on Cancer) system 1

Key prognostic factors assessed during staging:

• Primary tumor size
• Depth of invasion (critical for early-stage disease)
• Lymph node status (most important prognostic factor)
• Presence of lymphovascular space invasion (LVSI) 1

For tumors ≤2cm confined to vulva with <1mm invasion, imaging and lymph node assessment may be omitted 3

Common Pitfalls to Avoid

1. Misdiagnosis as inflammatory condition - Many vulvar cancers are initially misdiagnosed as benign inflammatory conditions, delaying proper treatment 4

2. Inadequate biopsy - Ensure biopsy includes sufficient depth to assess stromal invasion 1

3. Overlooking multifocal disease - Carefully examine entire vulva, vagina, and cervix 1

4. Relying solely on clinical lymph node assessment - Clinical palpation has high false-negative rate; imaging or sentinel lymph node biopsy may be needed 1

5. Delayed diagnosis - Any suspicious vulvar lesion should be promptly biopsied, as early diagnosis significantly improves prognosis 2

By following this systematic diagnostic approach, clinicians can ensure timely and accurate diagnosis of vulvar cancer, which is critical for appropriate treatment planning and improved patient outcomes.