Adenomyotic Cyst Masquerading as a Subserosal Fibroid: Always a Laparoscopic Surprise?

OBJECTIVE: To describe the clinical evaluation, diagnostic challenges, and laparoscopic management of a symptomatic uterine mass initially suspected to be a fibroid and ultimately confirmed as an adenomyotic cyst. SETTING: University-affiliated tertiary care hospital. PATIENT(S): A 41-year-old G4P2 woman with a 2-year history of chronic pelvic pain and severe dysmenorrhea refractory to NSAIDs, associated with heavy menstrual bleeding. She previously underwent hysteroscopic myomectomy. Examination revealed an enlarged, tender uterus, and transvaginal ultrasound demonstrated interstitial fibroids with cystic features, raising suspicion for a Müllerian anomaly or adenomyotic cyst. INTERVENTION(S): Laparoscopic excision of the lesion was performed and recorded as a surgical video. Incision of the lesion released characteristic "chocolate-like" content (Fig. 1). Indocyanine green injection demonstrated atypical fluorescence compared with fibroid tissue (Fig. 2), and comparison with typical fibroid uptake supported the diagnosis (Fig. 3). Complete excision and multilayer uterine reconstruction were achieved without entry into the uterine cavity. MAIN OUTCOME AND RESULTS: Histopathology confirmed adenomyosis without fibroid tissue. The patient experienced complete postoperative pain resolution. CONCLUSION: Adenomyotic cysts may mimic fibroids on imaging. Intraoperative assessment with indocyanine green facilitates accurate diagnosis and safe laparoscopic excision while preserving the uterus. VIDEO ABSTRACT.