Both mesonephric duct (Wolffian) and paramesonephric (müllerian) ducts exist in early embryo coexist at 6 weeks of gestation and develop into the reproductive organ of males or female[3-5]. In the male embryo, anti-müllerian hormone(AMH)secreted by the testicles can cause the degeneration of the müllerian duct and prevent the differentiation of female genitalia at the 10th week of gestation[6-8]. If the AMH secreted from the Sertoli cells is insufficient or AMH can’t perform its function due to various reasons, that will result in müllerian duct regress incompletely, causing MDRs[9, 10]. MDRs is associated with abnormal development of the urinary system such as intersex disorders, hypospadias and cryptorchidism[11-13]. 90% of these cases discovered in the pediatric age[11-13]. However, if the MDRs is revealed late in life, the patient usually appeared with normal external genitalia while it does not deprive the ability of the patient’s fertility[12, 14]. The patient of our case is discovered to suffer MDRs at the age of 58, presenting with normal external genitalia and father two healthy daughters. This patient has two healthy daughters. Therefore, his ability of fertility is not affected by müllerian duct remnants. And this patient is already 58 years old. Given the two reasons, we didn't take the semen analysis of the patient.
More than half of the MDRs patients had no obviously clinical symptoms[15]. Other patients may suffer from multifarious complaints include frequent micturition, urgency, urinary retention, dysuria, postvoid dribbling, low urinary tract infection, infertility and voiding dysfunction[8, 13-15]. And It's also been documented that MDRs can cause urine retention[15-17]. Ultrasonography, computed tomography scan and magnetic resonance imaging of the abdomen and pelvic cavity can provide important and valuable information for the diagnosis of this disease[18]. Ultrasonography is a helpful method in ascertaining the nature and scoping of the mass, nevertheless, it is a procedure of operator-dependent[19]. In this case, given the size of the mass, it's easy to find out this cystic lesion. CT scan and other imaging examination revealed a huge mass between the bladder and the rectum.
The major treatment method for symptomatic MDRs is surgical excision through laparoscope[3, 20, 21]. However, müllerian cysts can’t be excised completely for the müllerian duct stick to the bladder wall in most cases[22]. But doctors need to perform the surgery and remove partial of the cyst. The aim of this kind of surgery is reduce the size of mass and relieve the symptoms caused by the MDRs. The laparoscope is a perfect facility for procedures because it can provide a perfect view and show the anatomical relationships between the organs clearly[23]. However, the procedure of separating the adhesions between organs can be difficult. That’s because the cyst wall is stick to the surface of the bladder, prostate and pelvic floor muscle. Therefore, the process of separating the adhesion is time-consuming and prone to bleeding. The good news is that the patient recovered well after the operation and there are no reports in the literature that MDRs recurrent postoperatively[24]. After excision of müllerian duct, Aminsharifi et al., Hong et al. and Lima et al. reported no recurrence was found with 7 months, 3-56 months and 8-48 months follow-up in 2, 6 and 6 patients, respectively[20, 21, 25]. A three-month follow-up of the patient showed complete recovery of low back pain, besides, the image of the CT scan showed that the mass reduced visibly(the size of the mass is about 7×5×4cm) (Figure 4).
Laparoscopic excision is a perfect way for procedures need to be operated in restricted spaces. This method can provide a perfect view for operators and do minimally impair the patient compared to traditional procedures. Therefore, the patient can recover rapidly from this surgery.