Cyst of the canal of Nuck: an atypical course with cyclic changing of size.

As the canal of Nuck normally obliterates before birth, a patent canal is a rare anatomic variant in adult women analogue to the patent processus vaginalis in men. In a patent canal of Nuck, pathologies such as hernias and cyst can build within time. Such cysts themselves are so uncommon that they are mostly described in case reports. Normally, cysts of the canal of Nuck present as a consistent, inguinal swelling with or without pain. Interestingly, in our case, the painful swelling was cyclic changing from the size of a plum to being clinically undetectable within the course of a day. To the best of our knowledge, this is the first description of such an unusual course. The cyst was removed operatively via an open approach. The spasms declined shortly after the operation. At 1 year postoperatively, the patient was still asymptomatic.