Peritoneal Cyst of the Inguinal Canal Mimicking a Strangulated Femoral Hernia: A Case Report

Background: Femoral hernias may present as surgical emergencies because of their risk of incarceration and strangulation. Rare cystic lesions of the groin can produce similar clinical findings. Case Presentation: A 59-year-old woman with no relevant medical or surgical history presented with a left groin swelling that had been reducible and associated with a cough impulse for two months. During the four days before admission, the swelling became painful, irreducible and non-impulsive, without fever or other associated symptoms. Clinical examination suggested a tender, irreducible left femoral hernia with an estimated neck of 4 cm. Emergency exploration was undertaken without preoperative imaging. Within the inguinal canal, surgeons identified a 1 cm cystic lesion containing clear fluid, adherent to adjacent structures and bearing several whitish nodules on its wall. The lesion and its wall were biopsied, and approximately 400 mL of free peritoneal fluid was aspirated. No hernia requiring repair was identified. Histopathological examination showed fibrous, calcified peritoneal nodules and fibro-adipose hernial sac tissue with calcification. Immunohistochemical examination showed no evidence of carcinomatous cells. The postoperative course was uneventful. Conclusion: This case illustrates that a calcified, nodular peritoneal lesion within the inguinal canal may clinically resemble a strangulated femoral hernia. Histopathological assessment of unexpected operative findings helps distinguish benign tissue changes from possible malignancy.