<p>Incidental gallbladder cancer (iGBC) is discovered unexpectedly during histopathological examination after cholecystectomy, with the surgeon typically unaware of the malignancy at the time of surgery. Malignant cells have been demonstrated in the bile of patients with gallbladder cancer. Bile spillage during laparoscopic cholecystectomy is a common concern because it may lead to the dissemination of malignant cells, potentially resulting in widespread disease and poor oncological outcomes. The prognostic implications of bile spillage in iGBC patients remain uncertain, particularly regarding whether these patients should be staged as having metastatic disease and treated with palliative chemotherapy, or if curative resection should be pursued when the local pathology is resectable. To clarify this uncertainty, we conducted a systematic literature review to assess the impact of bile spillage on disease outcomes in iGBC patients. This review aims to shed light on the oncological consequences of bile spillage during cholecystectomy and guide clinical decision-making in the management of iGBC. A comprehensive search of the PubMed database, focusing on articles published up until September 2023 was made with the following search query: (“gallbladder neoplasms”[MeSH Terms] OR “neoplasm, residual”[MeSH Terms] OR “gallbladder diseases”[MeSH Terms] OR “carcinoma gallbladder”[Text Word] OR “gallbladder neoplasm*”[Text Word]) AND (“Incidental Findings”[MeSH Terms] OR “incidental”[Text Word] OR “incidentally detected”[Text Word] OR “incidental gallbladder carcinoma*”[Text Word] OR “incidental gallbladder cancer*”[Text Word]). Survival differences were our primary outcome. Secondary outcomes included the incidence of metastatic disease during staging prior to re-exploration, the occurrence of peritoneal carcinomatosis during re-exploration, success in achieving complete resection, the presence of residual disease identified through histopathology, and disease recurrence. Seven studies were analysed to study the impact of bile spillage on survival. The survival outcomes consistently indicated a poorer prognosis for patients with bile spillage compared with those without. Bile spillage led to higher incidence of peritoneal metastases and decreased possibility of curative re-resections. Bile spillage during the initial laparoscopic cholecystectomy has been shown to significantly worsen the prognosis of iGBC, consistently leading to poorer outcomes. Although the conclusions drawn from this review are limited by the retrospective design, potential confounders and biases, and inconsistent reporting in the available studies, they underscore the critical need for meticulous surgical techniques to prevent bile spillage in every laparoscopic cholecystectomy.</p>