RESUMO
To report a case of primary yolk sac [endodermal sinus] tumour [YST] of the vulva which is very rare and to highlight some unusual features of this tumour in the vulva. A 23-year-old woman presented with a 1-month swelling in the right labium majus that was non-tender and rapidly increasing in size. The mass was excised; it grossly measured 6 x 5 x 3 cm and was firm with a grey white cut surface. Microscopically it showed features of YST. The patient returned to the clinic only after 2 months with a recurrent mass of almost the same size with ipsilateral lymphadenopathy. At that time serum a-fetoprotein showed only a mild increase [13.4 micro g/l, normal: 0-10 micro g/l]. Further management was not possible as she decided to return to her native country for treatment. A literature review shows that local excision with lymphadenectomy followed by cisplatin-based chemotherapy is the best mode of treatment for primary YST of the vulva. This case is presented for its rarity and to highlight the fact that serum a-fetoprotein estimation may not aid in the primary diagnosis or detection of recurrence in patients on follow-up for YST arising in the vulva unlike those seen in the gonads