Novel application of transcervical radiofrequency ablation for symptomatic cystic adenomyosis. Case report

We report the case of a 35-year-old woman with a desire for future fertility who presented to our department with symptomatic cystic adenomyosis. The patient had primary dysmenorrhea since menarche, with a marked escalation over the past 5 years to severe, cycle-limiting pain (VAS 7/10). Hypermenorrhea developed and worsened over the last 2-3 years, requiring hourly changes of maximal-absorbency tampons during menses. She was G1P0. Her single prior pregnancy ended in a first-trimester miscarriage treated with curettage. The postoperative course was complicated by endometritis, which resolved after antibiotic therapy without sequelae. She had no other conditions or surgeries and no medical comorbidities. Transvaginal ultrasound revealed a normal-sized uterus with a cystic adenomyotic lesion measuring 2.5 × 2.5 cm located on the anterior uterine wall. The cyst was situated 9 mm from the serosal surface and 10 mm from the endometrial cavity ( Fig. 1 ). Fig. 1 Preoperative transvaginal ultrasound. White arrow indicates the cystic adenomyosis in the myometrium. Fig 1 Preoperative transvaginal ultrasound. White arrow indicates the cystic adenomyosis in the myometrium. Based on her clinical presentation, peritoneal endometriosis was also suspected. Conventional surgical approaches, including laparoscopic or hysteroscopic excision, were deemed suboptimal due to the cyst's deep intramyometrial location, which would necessitate extensive myometrial resection and potentially compromise uterine integrity. Simple drainage of the cyst was considered unsuitable due to the high risk of recurrence. After multidisciplinary discussion, transcervical RFA using the Sonata System was proposed as a uterus-sparing alternative for treating the cystic adenomyosis. Additionally, a laparoscopic procedure for suspected peritoneal endometriosis was planned. Preoperative hormonal therapy with dienogest (2 mg daily) was initiated because of severe symptoms. Three months later, the patient underwent combined transcervical RFA and laparoscopic surgery without complications. The cystic adenomyosis remained unchanged in size. Intraoperative real-time ultrasound guidance with graphical visualization of the ablation zone and safety margins facilitated precise and safe treatment ( Fig. 2 ). Fig. 2 Intraoperative ultrasound image with the Sonata System. Green arrow indicates the safety (green) zone. Red arrow indicates the ablation (red) zone. White arrow indicates the cystic adenomyosis. In the ultrasound image, the separation between the serosa and the cystic adenomyotic lesion is clearly visualized (blue arrow indicates the serosa). Fig 2 Intraoperative ultrasound image with the Sonata System. Green arrow indicates the safety (green) zone. Red arrow indicates the ablation (red) zone. White arrow indicates the cystic adenomyosis. In the ultrasound image, the separation between the serosa and the cystic adenomyotic lesion is clearly visualized (blue arrow indicates the serosa). The introducer needle allowed for drainage of the cyst's brownish fluid, followed by targeted ablation of the cyst capsule. The total ablation time was 3 minutes. Hysteroscopy revealed brownish, dense blood within the uterine cavity, consistent with the cystic content. Concurrently, laparoscopic excision of superficial peritoneal endometriosis (classified as #ENZIAN P2) was performed. Postoperatively, the patient continued hormonal therapy with dienogest until follow-up. At 6 months, she reported significant improvement in symptoms. Follow-up ultrasound confirmed complete resolution of the cystic adenomyosis, with only a small residual scar tissue measuring 1 × 0.4 cm ( Fig. 3 ). At this stage, discontinuation of hormonal therapy and pursuit of fertility were discussed. Fig. 3 Postoperative transvaginal ultrasound. White arrow indicates the residual scar of 1 × 0.4 cm. Fig 3 Postoperative transvaginal ultrasound. White arrow indicates the residual scar of 1 × 0.4 cm.

EP: manuscript writing, conception and design of the study data management, final approval of the submitted manuscript. TR: project development, conception and design of the study, revising it critically for important intellectual content, final approval of the submitted manuscript. EP and TR: contributed to patient care.

This case report was conducted according to 15§ of the professional code of the North Rhine Medical Association.

According to 15§ of the professional code of the North Rhine Medical Association IRB approval is not required for a retrospective case report, provided the all patient´s data is anonymized and the patient gives the written consent. All patient data were anonymized for the purposes of reporting. The patient gave a written consent.

The patient has given a written consent.

Transcervical ultrasound guided RFA may be a promising new therapy for cystic adenomyosis, offering effective lesion ablation with minimal invasiveness. In this case, RFA achieved substantial shrinkage of a large intramural cyst and resolution of symptoms while preserving uterine integrity. Compared to laparoscopic or hysteroscopic excision, RFA avoids major uterine incisions and may better safeguard fertility. This first reported use of transcervical RFA for cystic adenomyosis expands the treatment paradigm for adenomyotic disease. While more experience is needed, our findings suggest that RFA should be considered in selected patients, particularly those desiring future fertility. The case underscores the procedure’s novel role as a uterine preserving alternative to conventional surgery.

Cystic adenomyosis is an uncommon variant of adenomyosis characterized by one or more cystic cavities within the myometrium. Management strategies have historically been adapted from those for diffuse adenomyosis and fibroids. Laparoscopic excision has been used for large intramural cysts. For example, Li et al. reported a case of 38-year-old patient with a 104 × 55 × 60 mm cystic lesion on the posterior uterine wall who underwent laparoscopic cystectomy [ 9 ]. The cyst was completely resected and 1 month follow up ultrasound showed a normal uterine contour. In conclusion, the authors noted that “laparoscopic surgery is an effective method for the diagnosis and treatment of large cystic masses in the uterine myometrium” [ 9 ]. However, laparoscopic removal requires a uterine incision and suturing, which can weaken the myometrium and create adhesions. Such full thickness openings carry potential risks of uterine rupture or dehiscence in future pregnancies and may provoke intra peritoneal adhesions. Additionally, excellent surgical skills are required. Hysteroscopic approaches have also been explored, particularly for submucosal cysts. Small series have demonstrated that hysteroscopy can both diagnose and treat uterine cystic adenomyosis when lesions indent or bulge into the cavity [ 5 ]. For instance, Guo et al. retrospectively reviewed 5 cases of submucosal cystic adenomyosis: all patients underwent hysteroscopic resection of the cysts with no recurrences observed. They concluded that “hysteroscopy can not only diagnose submucosal cystic adenomyosis, but also treat it, and preserve the fertility function of the patient” [ 5 ]. Similarly, Xia et al. described hysteroscopic excision of myometrial adenomyotic lesions in a case series, reporting significant reductions in uterine volume and pain after resection [ 10 ]. These studies suggest that hysteroscopic fenestration or resection is feasible for accessible adenomyotic foci [ 10 ]. However, hysteroscopy is inherently limited to lesions near the endometrial cavity. Deep intramural cysts or those in the outer myometrium cannot be reached without extensive myometrial disruption. In Gordts et al., hysteroscopic ablation of cysts required creating a channel to the intramural cyst and used specialized instruments (eg, bipolar resectoscopic loops) to coagulate the lesion under ultrasound guidance [ 11 ]. Even then, only patients with portions of the cyst abutting the cavity could be treated. This hysteroscopic approach is technically challenging and carries a risk of damaging the surrounding uterine tissue. In short, conventional hysteroscopic methods are valuable for submucosal cystic adenomyosis [ 5 ], but deeply embedded lesions remain challenging. Both laparoscopic and hysteroscopic excision carry a risk of uterine tissue trauma. Laparotomy or laparoscopy involves sutured incisions that may compromise uterine integrity. Hysteroscopy can thin the myometrium or risk perforation if pushed too deep. Thus, especially for deep intramural lesions, traditional surgery can jeopardize future fertility. As noted in a recent case report, “conventional surgical approaches are traumatic to the uterine tissue,” highlighting the need for alternatives [ 7 ]. The myometrium of reproductive age women is particularly sensitive to injury: excessive resection can lead to scarring, abnormal wound healing, and potential placenta accreta in subsequent pregnancies. Moreover, large cysts may require interstitial vascular dissection and uterine repair, which prolong anesthesia time and blood loss. By contrast, transcervical intrauterine ultrasound guided RFA offers a uterus preserving, minimally invasive approach. Originally developed for fibroid treatment, the Sonata system (incorporating intrauterine ultrasound and a radiofrequency needle) has been gaining traction for adenomyosis. Recently we reported the series of focal adenomyosis treated with transcervical RFA: 30 patients underwent sonographically guided ablation via the cervix [ 6 ]. All procedures were uncomplicated, with a mean ablation time of only 8.5 minutes. By follow up, 89% of patients reported symptom improvement and the mean lesion diameter decreased from 4.4 cm to 2.8 cm [ 6 ]. Importantly, no patient’s symptoms worsened and all were satisfied. Similarly, we presented a case of a young woman with a 9.6 × 9.4 × 7.9 cm focal adenomyosis who underwent transcervical RFA [ 7 ]. Six months later her uterine volume and adenomyosis size were substantially reduced, and her dysmenorrhea improved. Consequently, it can be emphasized that RFA is “minimally invasive” and “uterine preserving,” constituting “a promising therapeutic alternative to conventional procedures such as hysterectomy and tissue excision.” Indeed, RFA avoids any extend incisions through the serosa or endometrium and ablates only the targeted lesion under continuous ultrasound guidance ( Fig. 2 ). The advantages of transcervical RFA for cystic adenomyosis are manifold: • Minimally invasive, uterus-preserving: RFA is delivered via the natural orifice of the cervix, without abdominal or vaginal incisions. The uterus remains intact except for the small needle tracks, greatly reducing scar formation [ 6 , 7 ]. The procedure preserves the uterine architecture and the endometrial cavity, which is crucial for fertility. • Treatment of deep intramural lesions: Because the intrauterine ultrasound probe provides real time imaging, RFA can target even deep intramural cysts that are inaccessible to hysteroscopic instruments. • Short procedure and rapid recovery: The reported mean ablation time in focal adenomyosis was only 8–9 minutes, and overall operative time was brief [ 6 ]. Patients can often go home the same day. This compares favorably to longer laparoscopic surgeries. Reduced anesthesia and blood loss also minimize morbidity. • High efficacy, low complication rate: Early evidence suggests excellent symptom control and lesion reduction. In our case series of focal adenomyosis, 89% of patients improved and no perioperative complications occurred [ 6 ]. The procedure’s safety profile is enhanced by real time visualization and automatic needle retraction if a tissue interface is not detected (a feature of the Sonata system). • Fertility preservation: By avoiding myometrial suturing, RFA leaves the uterus more intact. In younger patients desiring pregnancy, this is a key benefit. Early fibroid treatment studies with the Sonata system have reported subsequent pregnancies and normal obstetric outcomes [ 12 ]. In this case, preservation of the endometrial cavity and outer uterine wall was achieved ( Figs. 1 – 3 ), offering hope for future fertility. Minimally invasive, uterus-preserving: RFA is delivered via the natural orifice of the cervix, without abdominal or vaginal incisions. The uterus remains intact except for the small needle tracks, greatly reducing scar formation [ 6 , 7 ]. The procedure preserves the uterine architecture and the endometrial cavity, which is crucial for fertility. Treatment of deep intramural lesions: Because the intrauterine ultrasound probe provides real time imaging, RFA can target even deep intramural cysts that are inaccessible to hysteroscopic instruments. Short procedure and rapid recovery: The reported mean ablation time in focal adenomyosis was only 8–9 minutes, and overall operative time was brief [ 6 ]. Patients can often go home the same day. This compares favorably to longer laparoscopic surgeries. Reduced anesthesia and blood loss also minimize morbidity. High efficacy, low complication rate: Early evidence suggests excellent symptom control and lesion reduction. In our case series of focal adenomyosis, 89% of patients improved and no perioperative complications occurred [ 6 ]. The procedure’s safety profile is enhanced by real time visualization and automatic needle retraction if a tissue interface is not detected (a feature of the Sonata system). Fertility preservation: By avoiding myometrial suturing, RFA leaves the uterus more intact. In younger patients desiring pregnancy, this is a key benefit. Early fibroid treatment studies with the Sonata system have reported subsequent pregnancies and normal obstetric outcomes [ 12 ]. In this case, preservation of the endometrial cavity and outer uterine wall was achieved ( Figs. 1 – 3 ), offering hope for future fertility. Although transcervical RFA has a very low complication rate, potential risks include thermal injury to the endometrium or serosa (with rare perforation), bleeding or infection, incomplete ablation requiring reintervention, and—particularly for women desiring pregnancy—uncertain long-term obstetric effects. Strict adherence to ultrasound-guided safety margins is essential to mitigate these risks. This case represents, to our knowledge, the first report of transcervical RFA for cystic adenomyosis. It extends the applications of the Sonata system beyond fibroids and non-cystic adenomyomas to include this variant. Our findings are consistent with emerging literature on RFA in adenomyosis, highlighting its efficacy and safety [ 6 , 7 ]. Unlike conventional excisional surgery, RFA offers a fertility friendly alternative. For patients who wish to conceive, avoiding hysterotomy is paramount. Future follow-up and larger series are needed to establish long-term efficacy, impact on fertility, and recurrence rates. Nonetheless, our report highlights RFA’s potential to fill an important therapeutic gap. By circumventing the need for open surgery, transcervical RFA can minimize uterine trauma and expand treatment options for young women. The novel application described here may stimulate further research into minimally invasive management of complex adenomyotic lesions.

Adenomyosis is a common gynecological condition affecting women of reproductive age, characterized by the diffuse or localized infiltration of endometrial glands and stroma into the myometrium. Histopathological studies report its prevalence in hysterectomy specimens to range from 8.8% to 61.5% [ 1 ]. Cystic adenomyosis represents a rare variant of adenomyosis, distinguished by the presence of cystic lesions within the myometrium that contain old, brownish blood and lack communication with the uterine cavity [ 2 ]. First described by Dobashi et al. [ 3 ] in 1992, cystic adenomyosis typically presents with symptoms such as dysmenorrhea and chronic pelvic pain, both of which can significantly impair quality of life. The precise etiology and pathogenesis of cystic adenomyosis remain unclear [ 4 ]. Due to its low prevalence, literature on cystic adenomyosis is limited to case reports and small case series. Lesions can be located within the myometrium, or extend into the subserosal or submucosal layers [ 2 , 5 ]. Given the rarity of the condition, no standardized management strategies have been established. Surgical excision, either laparoscopic or hysteroscopic, has been the most commonly reported approach [ 2 , 5 ]. However, these techniques can be technically challenging and potentially traumatic to the surrounding myometrial tissue, particularly when lesions are located deep within the myometrium. Consequently, there is growing interest in exploring less invasive, uterus-sparing techniques for the management of adenomyosis [ 6 , 7 ]. Transcervical intrauterine ultrasound-guided radiofrequency ablation (RFA) has been developed as a minimally invasive treatment for uterine fibroids [ 8 ]. With accumulating experience in the management of fibroids, this technique has also been explored for the treatment of adenomyosis [ 6 , 7 ]. Transcervical RFA is a focal, volumetric, image-guided procedure that integrates intrauterine sonography with real-time radiofrequency energy delivery. The system enables precise visualization of the target lesion, delineates the ablation zone, and ensures a thermal safety margin beyond which surrounding tissues are not affected [ 8 ]. To the best of our knowledge, this is the first reported case of cystic adenomyosis treated using transcervical intrauterine ultrasound-guided RFA.