Brief Answer: Surgical excision and biopsy will confirm. Detailed Answer: Hello, Thanks for trusting us with your health concern. The most common cause of a cyst on the fallopian tube is an endometrioma, a form of endometriosis. This is a benign cyst. Endometriosis is a growth of tissue from the uterine lining in unusual places, such as the fallopian tube or ovary. The other major cause of fallopian tube cysts are paraovarian cysts, which are cystic structures which development from remnants of the fetal reproductive system. They are benign but can sometimes cause problems because they can get very large and rupture or twist. Often, a fallopian tube cyst goes away on its own without deliberate medical treatment. In case of large cysts surgical resection is considered. The histopathological examination after resection is the only way to confirm whether the cyst is benign or malignant. Please feel free to discuss further. I will be glad to answer the follow up queries that you have. Wishing you good health. Regards. Dr. Rakhi Tayal. For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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