Vulvovaginal myeloid sarcoma with massive pelvic floor infiltration: A case report and review of literature

BACKGROUND: Myeloid sarcoma (MS), including isolated and leukaemic MS, is an extramedullary myeloid tumour. MS can involve any anatomical site, but MS of the female genital tract is rare, with the ovaries and uterine body and cervix being the most commonly seen sites. Involvement of the vagina and vulva is extremely rare. CASE SUMMARY: We report a rare case of MS with involvement of the vulva and vagina and massive infiltration of the pelvic floor. A 26-year-old woman presented with a vulvar mass, irregular vaginal bleeding and night sweats. Magnetic resonance imaging demonstrated an ill-defined, irregular vulvovaginal mass with massive involvement of the paravaginal tissue, urethra, posterior wall of the bladder, and pelvic floor. The signal and enhancement of the huge mass was homogeneous without haemorrhage or necrosis. Positron emission tomography/computed tomography showed high fluorodeoxyglucose uptake by the mass. Peripheral blood count detected blast cells. Vulvovaginal mass and bone marrow biopsies were performed, and immunohistochemistry confirmed the diagnosis of acute myeloid leukaemia (M-2 type, FAB classification) and vulvovaginal MS. The patient was treated with induction chemotherapy followed by allogeneic haematopoietic stem cell transplantation, and achieved complete remission. A systemic review of the literature on vulvovaginal MS was conducted to explore this rare entity’s clinical and radiological features. CONCLUSION: Vulvovaginal MS is extremely rare. Diagnosis of vulvovaginal MS can only be confirmed histopathologically. Even though its clinical and imaging presentations are nonspecific, MS should be considered in the differential diagnosis of a newly developed T2-hyperintense, homogeneously enhanced vulvovaginal mass, especially in a patient with suspected haematological malignancy.