BACKGROUND: Leiomyoma with secondary changes arising from Mullerian remnant may mimic ovarian tumor in women with Mayer-Rockitansky-Kuster-Hauser (MRKH) syndrome in patients with pelvic mass and urologic abnormalities.

CASE DETAIL: The patient was a 40 years old known case of MRKH, presented with lower abdominal pain and swelling for over one year. On physical examination, large pelvic mass (about 15cm by 10cm) was found and a diagnosis of ovarian tumor was made by imaging which also showed absent right kidney. Finally, the mass was found to be a big leiomyoma with areas of hyaline, edematous and cystic degenerations.

CONCLUSION: Although leiomyoma arising from rudimentary Mullerian bulb is a rare condition, it should be considered in differential diagnosis of pelvic mass in patients with MRKH. Possibility of urologic abnormalities should also be considered in these patients and appropriate work up per local context should be made.