Endometriosis is a complex disease characterized by the presence of endometrial-like tissue outside the uterine cavity. While commonly affecting the pelvic organs, extra pelvic endometriosis (EPE) is a rare but clinically significant condition that requires specialized surgical expertise. The estimated prevalence of EPE is approximately 12% of all endometriosis cases, with the diaphragm being the most common site, affecting 1-1.5% of patients with endometriosis. Less frequent locations include the spleen (<0.5% of cases), pancreas, and pericardium (extremely rare, with isolated case reports). This video article presents four cases of extra pelvic endometriosis, all of which were operated on by our multidisciplinary team: (1) splenic endometriosis requiring splenectomy, (2) diaphragmatic and pericardial endometriosis, (3) diaphragmatic endometriosis, and (4) a ten cm retroperitoneal endometriotic cyst posterior to the pancreas. The article highlights the necessity of a multidisciplinary surgical approach, including gynaecologists, colorectal surgeons, CT and HPB surgeons. Given the complexity of extra pelvic lesions, a surgeon with expertise in endometriosis is crucial for achieving complete excision while preserving organ function. Additionally, this article aims to demonstrate that, although infrequent, extra pelvic endometriosis exists and should be considered in the differential diagnosis when patients present with atypical symptoms. Mapping the disease according to symptoms is essential to achieving a comprehensive diagnosis of deep endometriosis.

This video article illustrates the complexity and surgical management of extra pelvic endometriosis (EPE) through four representative cases. It highlights the importance of clinical suspicion based on symptoms, strategic use of advanced imaging, and the fundamental role of a multidisciplinary team in achieving complete disease excision. Despite its rarity, EPE must always be considered in patients with cyclical symptoms in atypical locations.

Endometriosis affects approximately 10% of reproductive-aged women, with extra pelvic manifestations reported in up to 12% of cases. Among the most frequently described sites of extra pelvic endometriosis (EPE), diaphragmatic involvement accounts for 1–1.5%, whereas splenic, pancreatic, and pericardial locations are exceedingly rare. Due to its infrequency and wide spectrum of clinical presentations, EPE is frequently misdiagnosed or overlooked, often resulting in delays in appropriate treatment. Effective management of EPE requires a comprehensive surgical approach and the coordination of a multidisciplinary team to ensure both safe and complete disease excision. Crucially, accurate diagnosis depends not only on advanced imaging but also on a high index of clinical suspicion. In the absence of gynecologic symptoms, EPE may mimic other systemic conditions, and imaging studies are often only pursued when the treating physician is guided by a careful symptom-based evaluation.

This study highlights the importance of systematically considering extra pelvic manifestations in the diagnostic workup of patients with non-specific or cyclic symptoms in atypical anatomical regions. By integrating symptom-guided mapping and collaborative surgical planning, clinicians can move toward a more complete and timely diagnosis of deep endometriosis, including its extra pelvic forms.

All patients underwent standardized preoperative imaging, including:

• Transvaginal and abdominal ultrasound.
• MRI with extra pelvic extension.
• Postoperative histopathological confirmation.

Each surgery was performed by a high-complexity multidisciplinary team, including:

• Expert gynecologic endometriosis surgeons
• Colorectal surgeons
• Cardiothoracic surgeons (CT)
• Hepatopancreatobiliary surgeons (HPB)

Case 1: A 34-year-old patient with splenic endometriosis presenting with cyclic left upper quadrant pain, dyspnoea, bloating, and anaemia. MRI with abdominal extension was performed, revealing a well-defined cystic lesion in the spleen with imaging characteristics consistent with endometriosis.

Case 2: A 40-year-old patient with diaphragmatic and pericardial endometriosis, presenting with cyclic chest pain. Initial transabdominal ultrasound revealed hyperechoic foci along the left diaphragmatic line. MRI confirmed left diaphragmatic involvement.

Case 3: A 36-year-old patient with diaphragmatic endometriosis, presenting with cyclic right upper quadrant pain, referred shoulder pain, and respiratory discomfort. Ultrasound examination showed hyperechoic foci along the diaphragmatic line. MRI confirmed the presence of diaphragmatic endometriotic lesions.

Case 4: A 38-year-old patient with a 10 cm retroperitoneal endometriotic cyst located posterior to the pancreas, initially suspected to be a pancreatic pseudocyst. The patient presented with epigastric pain, mainly when lying down, nausea, early satiety, and intermittent vomiting. MRI with abdominal extension was performed, revealing a well-circumscribed cystic lesion suggestive of endometriosis.

No intraoperative complications across cases Hospital discharge <72 hours in all patients

• Histological confirmation of EPE in all lesions
• Significant symptom improvement reported at 6-month follow- up
• No recurrence reported at latest follow-up

EPE presents unique diagnostic and therapeutic challenges. The incidence of extra pelvic involvement varies, with the most affected sites being the diaphragm and gastrointestinal tract; while splenic, pancreatic, and pericardial endometriosis remain exceedingly rare. Complete surgical excision remains the gold standard for symptom relief and disease control, emphasizing the necessity for an endometriosis expert with a thorough understanding of both pelvic and extra pelvic disease manifestations.
A multidisciplinary approach is crucial, involving:

• Gynecologists specialized in endometriosis for overall disease assessment and pelvic management.
• Colorectal surgeons for bowel involvement.
• Cardiothoracic surgeons for thoracic endometriosis cases.
• Hepato-pancreatobiliary (HPB) surgeons for pancreatic and splenic cases.

The complexity of these cases underlines the need for a comprehensive surgical strategy tailored to the individual patient. Without expertise in extra pelvic endometriosis, incomplete excision or unnecessary radical procedures may compromise outcomes.

Additionally, this study highlights the importance of symptom-based disease mapping. Given that EPE can mimic various pathologies, a structured approach to diagnosis is essential. Patients with cyclical pain in atypical locations should undergo targeted imaging and evaluation for possible extra pelvic endometriosis. Without proper recognition of these symptoms and a multidisciplinary approach, many cases may remain undiagnosed or misdiagnosed.

Given the rarity and complexity of extra pelvic endometriosis (EPE), surgeons and gynaecologists specializing in endometriosis must expand their diagnostic and surgical expertise beyond the confines of the pelvis to ensure optimal patient outcomes. Successful management requires not only technical proficiency but also the integration of a multidisciplinary team – including colorectal, hepatopancreatobiliary, and cardiothoracic surgeons – aligned according to the specific anatomical involvement. Accurate diagnosis depends on symptom-guided evaluation rather than incidental imaging findings. In patients presenting with cyclic pain in non-pelvic locations, a deliberate and structured approach to clinical mapping is essential. Without it, EPE may go undetected or be misattributed to other pathologies, delaying appropriate treatment. This video article serves as a call to heightened clinical awareness and multidisciplinary collaboration. By recognizing atypical symptom patterns, applying targeted imaging strategies, and engaging expert surgical teams, healthcare professionals can significantly improve diagnostic accuracy, surgical outcomes, and long-term quality of life for women affected by extra pelvic endometriosis.