OBJECTIVE To investigate the long-term outcome of patients presenting with vulvar intraepithelial neoplasia (VIN) with superficially invasive carcinoma of the vulva (SICa). METHODS A retrospective study using information obtained from patient case notes. METHODS Twenty-six women found at presentation to have VIN in association with superficially invasive carcinoma were identified during a 15-year period. RESULTS Pruritus vulvae was the most frequent presenting symptom in 18 patients (69%). Sixteen women (61.5%) had multiple symptoms. Features noted at vulvar examination were variable and none were pathognomonic of either VIN or of superficial invasion. All patients had VIN 3 in association with a superficially invasive carcinoma. Histological changes associated with human papillomavirus were found in 19 (73%) women. Half had a co-existent or previous abnormality of the lower genital tract. Local excision was the most frequent initial treatment (n = 9 [35%]). Mean follow up time was 65 months (range 12-174). Disease persisted after primary treatment in five women (19%). Both histological recurrence (of either VIN or SICa) or symptomatic recurrence occurred in 10 patients (38%). All patients who experienced recurrence did so within 36 months of treatment. Overall, 12 patients (46%) relapsed (histological or symptomatic recurrence); the mean time was 18 months. Fourteen patients (54%) were managed satisfactorily by their initial treatment. One patient died of recurrent cervical cancer. Three progressed to frankly invasive disease: two (aged 31 and 39 years) with carcinoma of the vulva and one aged 34 years with carcinoma of the perianal margin. All are alive and well after treatment. One patient had recurrence of superficially invasive carcinoma treated by local excision with no further problems. No episode of metastasis via lymphatic or vascular channels has been seen. CONCLUSIONS Patients with superficially invasive carcinoma of the vulva may be safely treated by local excisional methods without recourse to lymphadenectomy. Relapse after primary treatment is common, and there appears to be a significant risk of progression to frankly invasive carcinoma.