Diagnosis and Management of Scrotal Wall Mass with the Aid of Scrotoscope: Case Series Report

Background Scrotal wall mass is relatively rare in clinical practice, and very dicult to be differentiated from scrotal content lesions by physical or ultrasound examination. Herein, we would like to share the experiences of scrotoscope in diagnosis and treatment of Scrotal wall masses. Retrospectively reviewed all the clinical data of scrotal wall mass patients treated by our medical team between June 2015 and July 2019. The diagnostic value was evaluated by comparing with Doppler ultrasound examination and the therapeutic value was evaluated by comparing with traditional surgery. Suspected scrotal tuberculosis or malignant scrotal tumor patients were excluded. could provide us necessary information for proper management 2–5 . In some cases, we can resect the scrotal masses directly under scrotoscope 2, 6–8 . This study was conducted to share the experiences of scrotoscope in diagnosis and treatment of Scrotal wall masses.


Background
Scrotal wall mass is relatively rare in clinical practice, and very di cult to be differentiated from scrotal content lesions by physical or ultrasound examination. Herein, we would like to share the experiences of scrotoscope in diagnosis and treatment of Scrotal wall masses.

Methods
Retrospectively reviewed all the clinical data of scrotal wall mass patients treated by our medical team between June 2015 and July 2019. The diagnostic value was evaluated by comparing with Doppler ultrasound examination and the therapeutic value was evaluated by comparing with traditional surgery.
Suspected scrotal tuberculosis or malignant scrotal tumor patients were excluded.

Results
Totally, 6 patients with scrotal wall masses were diagnosed and treated with scrotoscope. Preoperative ultrasound examination leaded to ambiguous or incorrect diagnosis of the origination of scrotal wall masses in all the 6 cases. The location of all the masses was clearly con rmed by scrotoscope exploration. Three patients were diagnosed as scrotal wall cysts, and 1 of them was successfully resected during the procedure, the other 2 were resected through small incision. In the other 3 patients, a total of 4 scrotal wall solid masses were resected through small incision after diagnosis by scrotoscope.
There was no wound infection, scrotal edema, hematoma, chronic scrotal pain or injury of testicular or epididymis.

Conclusions
Scrotal wall masses are relatively rare, and it is very di cult for preoperative ultrasound examination to make a rm diagnosis of its origination. Scrotoscope can con rm the localization of the tumor, and provides us important information for minimally invasive resection. And even in some cases, endoscopic resection of the masses can be performed under scrotoscope.

Introdution
The scrotal wall could be involved in various primary and secondary pathological processes, which might lead to a large variety of lesions 1 . In fact, scrotal wall mass is relatively rare in clinical practice, and very di cult to be differentiated from scrotal content lesions by physical or ultrasound examination, which brought us a certain degree of trouble to make an appropriate therapeutic regiment. With the aid of scrotoscope, we could observe and determine the nature of the scrotal mass directly, which could provide us necessary information for proper management [2][3][4][5] . In some cases, we can resect the scrotal masses directly under scrotoscope 2, 6-8 . This study was conducted to share the experiences of scrotoscope in diagnosis and treatment of Scrotal wall masses.

Patients
From June 2015 to November 2019, all scrotal mass patients treated by our medical group were retrospectively reviewed. Patients diagnosed as scrotal wall masses with the aid of scrotoscope were selected for further study. Clinical data including age, ultrasound results, scroscopy results, surgery method, surgery time, wound size, complications, pathological results and follow-up time were collected. The diagnostic value was evaluated by comparing with Doppler ultrasound examination and the therapeutic value was evaluated by comparing with traditional surgery. Suspected scrotal tuberculosis or malignant scrotal tumor patients were excluded. Before scrotoscope exploration, Ultrasonography was performed in all patients by two experienced radiologists.

Scrotoscopy
Scrotoscope exploration was performed using either Fr 17 to Fr 22 Storz (Germany) cystoscope or Fr 26 Olympus (Japan) plasma resectoscope. The patient was placed in a lithotomy position. Sterile saline perfusion was maintained at 60-80-centimeter hydraulic pressure with a low-ow mode continuously. On the anterior wall of scrotum, a 1-cm wide incision was made, until the perididymis was reached. Two Allis tissue clamps were used to x the entire layer of the scrotal wall along the incision to make sure scrotoscope can be further inserted into the testicular vaginal cavity (Fig. 1,2). The scrotal contents and scrotal wall were carefully inspected with the aid of scrotoscope.

Open surgery
Surgery was performed by at least two experienced scrotoscope surgeons. The incision for scrotoscopy was placed 1 cm down to the expected location of the scrotal wall mass. If the mass was observable on the inner wall of scrotum during the scrotoscope exploration and was considered benign, we resected the mass directly with plasma resectoscope. If the mass was unobservable during the scrotoscope exploration, we make another incision right on the expected mass location of the scrotal wall to resect it with open surgery.

Results
Of the 44 scrotal mass cases diagnosed or treated with the aid of scrotoscope by our medical group, only 6 (13.6%) were scrotal wall masses. In these 6 cases, the median age of patients was 46.5 years old, ranged from 25 to 64 years old. Preoperative ultrasound examination leaded to ambiguous or incorrect diagnosis of the origination of scrotal masses in all the 6 cases. But the scrotal wall origination was all clearly con rmed by scrotoscope exploration. The whole treatment procedure was completed successfully in all the 6 patients with a median operating time of 32 minutes (range, 25-50 minutes). Meanwhile, the median time to diagnostic and resection were 2 minutes (range, 1-4 minutes) and 8 minutes (range, 5-11 minutes) respectively.
Three patients were diagnosed as scrotal wall cysts (one multilocular cyst, two solitary cysts), 1 of them was successfully resected during the procedure and the other 2 were resected through small incisions. In patient NO.5, we found two solid-cystic scrotal content lesions located on both epididymides as

Discussion
Intrascrotal mass is a common nding in the male population. Most of them originated from the scrotal contents, such as the testicles and epididymis.
While scrotal wall mass is relatively rare 9 . Unlike scrotal content masses, which are 90% malignant, scrotal wall masses are more likely benign.
Ultrasonography is the most common diagnostic test for intrascrotal masses, which has a moderately good diagnostic value to its nature, but relatively low diagnostic value to its exact location 1,10 . As showed by our study, ultrasonography precisely diagnosed the cyst nature of 3(50%) scrotal wall masses and roughly describe the benign appearance of the other 3 scrotal wall masses. As for the mass position, ultrasonography failed to make a reliable description in all the 6 cases, which brought us a certain amount of trouble in the further therapeutic regimen making. Diagnosis of the origination is challenging because of the complicated anatomic structure within the scrotum. In fact, successfully distinguishing scrotal wall mass and scrotal content mass, instead of precisely describing its position, will be enough to help us make a proper therapeutic regimen. Herein, we introduce a new minimally invasive method, which is called scrotoscope, to help us distinguish scrotal wall masses from scrotal content masses.
Scrotoscope is a kind of endoscope which can be performed in the scrotum 2,5,11 . With the aid of scrotoscope, we can explore and observe the structures within the scrotum, such as testis, epididymis and the scrotal wall. During the procedure, we can make rm diagnosis and perform proper treatment to the intrascrotal lesions. Scrotoscope was rstly reported by Sha k to explore the scrotal content in 1986 worldwide 12 . In China, scrotoscope was rst reported by our group to diagnose intrascrotal lesions in 1992. In this research, our group rstly conduct a study to introduce the experiences of scrotoscope in the diagnosis and treatment of scrotal wall masses.
As demonstrated by our study, scrotoscope has a moderately good diagnostic value to the nature of only a small part of scrotal wall masses. But it can rmly con rm the position of most scrotal wall masses. Therefore, while the benign nature has been roughly determined by ultrasound examination, scrotoscope examination can be used as a necessary supplement to further clarify the origination of intrascrotal masses and provide su cient basis to make a proper surgery plan. In some cases, scrotoscope can be used as a therapeutic procedure. In our study, the scrotal inner wall cyst of patients NO.2 could be observed with the aid of scrotoscope and the cyst was directly resected under scrotoscope. After 24-month's follow-up, no recurrence was observed in this patient. In other 5 cases, the scrotal wall masses were resected ed by open surgery with small incision, after the scrotal wall origination had been con rmed by scrotoscope exploration. After 6 to 24 months' follow-up, no recurrence or metastasis were observed in all these patients.
In terms of safety, edema and hematoma of scrotum, incision infection, injury of spermatic cord, torsion of testis, chronic scrotal pain and orchiatrophy were common complications after scrotoscope exploration 13,14 . But, none of these complications was observed in all the 6 patients of our study during a median follow-up of 21 months. Scrotal edema is the most common complication after scrotoscope exploration by inexperienced scrotoscope surgeons.
For patients with scrotal edema after scrotoscope exploration, the main cause is the damage of perididymis or in ltration of perfusion uid through the incision into the interlayer of the scrotal wall 3 . Therefore, the total layer of scrotal wall incision should be completely clamped with Allis tissue forceps during the procedure. Meanwhile, attention should be paid to control the perfusion uid pressure. According to our experience, it should be maintained as 60-80-centimeter hydraulic pressure. Once scrotal edema occurs, the operating time should be reduced as possible as you can to effectively reduce the severity of edema. Even if scrotal edema occurred eventually, most of them were expected to go down within 24 to 48 hours, if properly pressurized.

Conclusion
In recent years, scrotoscopy had been widely used in the diagnosis and treatment of variety scrotum diseases, such as scrotal content masses and testicular torsion. But as far as we know, this is the rst study conducted to evaluate the diagnostic and therapeutic value of scrotoscopy in scrotal wall masses. As showed by our study, scrotoscopy was a safe and effective technique in the diagnosis and treatment of scrotal wall masses. It could be used as an important supplement of Ultrasonography and open surgery in scrotal wall mass's diagnosis and treatment respectively. But, owning to the retrospective design and small sample size of our study, more well-designed clinical trials will be warranted to determine its value.

Declarations
Author's contribution RZ prepared the draft of manuscript. YG and TL collected the data. QZ and LY participated in the cases diagnosis and management and follow-up. JY and YW sponsored the study and took part in the paper editing. All authors read and approved the nal manuscript.
Ethics Statement.
The approval for this study was obtained from the Fujian Provincial Hospital. Written informed consents were obtained from the guardians of these patients. Identifying information was removed from the study. All data were kept by only the administrator of the study in a con dential manner and was not used by any other purposes. The methods were performed in accordance with the relevant guidelines and regulations.