RESUMEN
BACKGROUND: Malignant tumours of the vulvar soft tissue are very uncommon. When localized in the Bartholin's gland area these tumours can be mistaken for benign lesions, leading to a delayed diagnosis. CASE: A 52-year-old woman presenting with a vulvar nodule, which was diagnosed as a Bartholin's gland cyst and was referred to the hospital for surgical excision of the lesion. Pathologist report informed of a 6 cm diameter leiomyosarcoma of the vulva with compromised resection margins; extension studies did not suggest any additional lesions and radical hemivulvectomy with ipsilateral inguinal lymphadenectomy was performed. The patient subsequently received radiotherapy and chemotherapy. Twelve months later, a local recurrence was diagnosed and was removed surgically. After 4 years of follow-up the patient remains disease free. CONCLUSION: Any vulvar lesion with unusual characteristics or insidious evolution in labia majora or Bartholin's glands area should be carefully and promptly studied. This is particularly important in order to perform an effective surgical treatment in cases of leiomyosarcoma.