Management of Vulvar Carcinoma In Situ
For a patient with carcinoma in situ of the vulva, surgical excision is the most appropriate management—specifically wide local excision with 1-2 cm margins to ensure complete pathologic assessment and exclude occult invasion. 1, 2, 3
Why Surgical Excision Over Laser Ablation
Surgical excision is superior to laser ablation because it provides tissue for pathologic examination to exclude microinvasion or occult invasive disease, which occurs in up to 7% of high-grade vulvar lesions. 3 This is the critical distinction: laser ablation destroys tissue without allowing histologic confirmation of invasion depth, potentially missing early invasive cancer that would require lymph node evaluation. 3
The NCCN explicitly recommends conservative individualized tumor excision for early vulvar lesions, with wide local resection or radical local resection as the standard approach for T1 tumors. 1, 2 Historical data confirm that untreated vulvar carcinoma in situ, particularly in middle-aged and elderly women with multifocal disease, progresses to invasive carcinoma in 2-8 years. 4
Specific Surgical Technique
Target 1-2 cm surgical margins around the lesion if anatomically feasible to ensure complete excision while preserving vulvar function. 1, 2, 3
Resection depth should extend to the urogenital diaphragm to ensure adequate depth of excision and complete removal. 1, 3
Use separate incisions for different lesions rather than en bloc resection to minimize morbidity and preserve vulvar anatomy. 2, 3
Critical Point: No Lymph Node Evaluation Required
**Inguinofemoral lymph node evaluation is NOT required for true carcinoma in situ because the risk of lymphatic metastases is <1%.** 1, 2 Lymph node dissection is only indicated if final pathology reveals >1 mm depth of invasion. 1, 2 This is a common pitfall—never perform lymphadenectomy for carcinoma in situ unless invasion is confirmed. 1
Post-Excision Management
If surgical margins are negative and no invasion is identified, observation alone is appropriate. 1
Follow-up schedule: Every 3-6 months for 2 years, then every 6-12 months for years 3-5, then annually. 1
HPV testing at 6 months post-treatment is highly sensitive for detecting recurrent disease. 3
Continued surveillance for at least 20 years is necessary as women remain at elevated risk for invasive cancer long-term. 3
When Laser Ablation Might Be Considered (Not Preferred)
While CO₂ laser ablation has been used historically for vulvar carcinoma in situ with acceptable recurrence rates 5, it cannot provide tissue for pathologic examination and is associated with higher rates of subsequent invasive cancer diagnosis. 3 Laser should only be considered after excisional biopsy has definitively excluded invasion, and even then, excision remains preferred. 3
If Final Pathology Shows Invasion
If final pathology reveals >1 mm invasion, additional surgery with inguinofemoral lymph node evaluation becomes necessary. 1, 2 For invasion >1 mm, treatment depends on tumor location: