Incidental discovery of abdominal splenosis mimicking metastatic disease during elective incisional hernia repair: a case report

BACKGROUND: Abdominal splenosis is a benign condition that occurs when splenic tissue is implanted within the abdominal cavity after splenic trauma or splenectomy. Most patients remain asymptomatic, and the condition is often detected incidentally. However, when multiple nodules are present, they can closely resemble peritoneal metastases and create uncertainty, particularly when they are encountered unexpectedly during surgery. A lack of awareness may lead to overly aggressive surgical decisions or delays in definitive management. CASE PRESENTATION: We describe a patient in whom abdominal splenosis was incidentally identified during the repair of an incisional hernia associated with a chronic discharging sinus. During exploration, numerous reddish-brown nodules were noted over the omentum and peritoneal surfaces, raising concern for peritoneal carcinomatosis, especially given the patient's family history of colorectal cancer. A few representative nodules were excised and sent for histopathological examination. Intraoperative frozen section analysis was not performed, and therefore, the decision to proceed was based on gross intraoperative findings. In the absence of frozen-section confirmation, the decision to proceed with mesh repair was made based on the benign intraoperative appearance of the nodules (well-circumscribed, non-infiltrative, no ascites), and a clean operative field without evidence of infection. Considering these findings, the surgical team proceeded with definitive mesh repair of the hernia during the same operation. Histopathology later confirmed the presence of splenic tissue consistent with splenosis. The patient had an uneventful postoperative recovery. CONCLUSION: This case demonstrates that intraoperative recognition of splenosis, supported by careful assessment and limited biopsy, allows safe continuation of planned surgery without unnecessary delay or overtreatment. Awareness of this entity is essential to guide appropriate intraoperative decision-making and avoid misinterpretation as metastatic disease.