Case Report: Retained gallstone migrating to the chest wall after cholecystectomy presenting as chronic abscess, sinus tract, and inflammatory pseudotumor.

BACKGROUND

Gallbladder perforation and gallstone spillage are common during laparoscopic cholecystectomy, occurring in up to 40% and 6%-10% of cases, respectively. While most retained stones remain asymptomatic, 2.3%-8.5% of patients may present with intra-abdominal abscess, granuloma formation, abdominal wall sinus, fistula or a mass mimicking a malignancy (1). We report a unique case of a retained gallstone migrating to the chest wall 2 years after cholecystectomy, forming a chronic abscess, sinus tract, and inflammatory pseudotumor.

CASE PRESENTATION: A 61-years-old woman with a history of laparoscopic cholecystectomy 2 years prior presented with a 1-month history of right chest pain and a palpable chest wall mass. Computed tomography (CT) revealed a 2.4 cm × 2.2 cm soft tissue mass adjacent to the right 10th rib with an internal ring-like hyperdensity, focal rib erosion, and pleural thickening. Magnetic resonance cholangiopancreatography (MRCP) showed a nodular T2 hypointense lesion (approximately 2.7 cm) adjacent to the right hemidiaphragm and posterior to the right hepatic lobe, with surrounding inflammatory exudation and ipsilateral chest wall soft tissue swelling, along with a small right pleural effusion and intrahepatic bile duct stones. The chest wall lesion was initially concerning for malignancy. At surgery, a 6 × 5 × 4 cm cystic mass was excised from the right posterolateral chest wall. Inside the cyst, a 3 cm spherical gallstone was found embedded in purulent material, with a sinus tract extending toward the pleura. Histopathology showed chronic suppurative inflammation, abscess formation, multinucleated giant cells, and granulation tissue, consistent with inflammatory pseudotumor secondary to foreign body reaction. The patient recovered uneventfully and remained asymptomatic at 6-months follow-up.

CONCLUSION

Gallstones spilled during cholecystectomy can migrate to extra-abdominal sites years later, causing chronic chest wall pathology that mimics malignancy. A ring-like hyperdensity on CT and a T2 hypointense nodule on MRI in a post-cholecystectomy patient should raise suspicion for a retained gallstone. Complete surgical excision is curative.