From First Breathless Episode to Final Diagnosis and Treatment: A Case Report on Thoracic Endometriosis Syndrome

<b>Background:</b> Endometriosis is a chronic disease defined by the presence of endometrial-like tissue outside the uterine cavity. While typically confined to the pelvis, extrapelvic manifestations-including thoracic endometriosis-can occur. Although rare, thoracic endometriosis is the most common extragenital form. In clinical practice, this presentation is often described as thoracic endometriosis syndrome (TES), a constellation of cyclic thoracic symptoms temporally associated with menstruation but not always histologically confirmed. Its atypical symptoms and limited clinical awareness frequently lead to delayed diagnosis, mismanagement and increased patient burden. <b>Methods:</b> In accordance with the CARE guidelines, we present a case report of a female patient with thoracic endometriosis syndrome, emphasizing the prolonged interval between symptom onset and final diagnosis. <b>Case Report:</b> We describe a 42-year-old woman with a longstanding history of dysmenorrhea and menorrhagia, who developed cyclical chest pain and dyspnea in 2019. Despite multiple thoracoscopic procedures, her symptoms persisted and were repeatedly misattributed to anxiety or infection. Thoracic endometriosis syndrome (TES) was suspected in 2022, and although histopathological confirmation was lacking, intraoperative visualization revealed diaphragmatic fenestrations. In 2025, a second laparoscopic intervention targeting the abdominal surface of the diaphragm resulted in significant symptom relief. The patient is currently continuing hormonal therapy with Dienogest and has reported a marked improvement in quality of life. Nevertheless, the protracted diagnostic and therapeutic process-marked by chronic pain and repeated hospitalizations-had a profound psychosocial impact, culminating in a suicide attempt. <b>Conclusions:</b> This case illustrates the substantial burden associated with the delayed recognition of thoracic endometriosis syndrome and the consequences of fragmented care. The patient's experience underscores the urgent need for coordinated, multidisciplinary management and psychological support, particularly for patients with extrapelvic manifestations. Early multidisciplinary evaluation, with readiness to consider surgical intervention alongside individualized hormonal therapy, may support improved outcomes, provided they are reinforced by increased clinical awareness and systemic improvement in diagnostic pathways.