Abstract
BACKGROUND: Gallbladder cancer (GBCA) is the most common malignancy of the biliary tract. It has an aggressive biology that results in the ability to spread, seed and grow in disparate environments. It can metastasize via lymphatic, hematogenous, and peritoneal seeding. However, GBCA metastasis to distant subcutaneous sites is extremely rare. CASE PRESENTATION: This case report describes the presentation of metastatic GBCA with rapidly progressive subcutaneous metastases. A 58-year-old woman presented with acute onset right upper quadrant abdominal pain. Computed tomography (CT) revealed a calcified and thickened gallbladder with cholelithiasis and presumed cholecystitis. Diagnostic laparoscopy revealed a gallbladder mass. Biopsies were consistent with GBCA. The patient was referred to our cancer center for further surgical management. However, she was found to have rapidly growing subcutaneous nodules in the shoulders, chest, abdomen, and buttocks. Positron emission tomography (PET) demonstrated that these were fluorodeoxyglucose (FDG)-avid. A core needle biopsy of a chest wall lesion was consistent with metastatic GBCA. Therefore, the patient was diagnosed with stage IVB GBCA and was initiated on systemic chemotherapy. DISCUSSION: GBCA is known to have an incredible propensity to grow within the peritoneal cavity, as well as along needle biopsy tracts and at laparoscopic port sites. Several case reports have demonstrated that GBCA also has the potential to metastasize to distant subcutaneous sites, most often including breast metastases, while the current cases represents a more diffuse pattern of spread. CONCLUSIONS: GBCA belongs to the short list of solid visceral malignancies that have the potential to develop remote subcutaneous metastases.