Beyond the Initial Impression: Diagnostic Anchoring in an Elderly Patient With Metastatic Gallbladder Cancer

Persistent nonspecific symptoms in older adults can be diagnostically challenging, particularly when a plausible pre-existing diagnosis provides a satisfactory explanation.We report the case of a 72-year-old woman with a three-month history of chronic fatigue occurring in the context of a persistent ear infection and known cholesteatoma awaiting surgery.Her fatigue had previously been attributed to the otologic condition during repeated primary care consultations.She subsequently presented to the emergency department with worsening fatigue and five days of bilateral lower limb swelling and was found to have tachycardia, with a heart rate of 129 beats/minute, blood pressure of 110/70 mmHg, temperature of 37.3°C, and oxygen saturation of 95% on air.Given the physiological abnormalities and inflammatory response, an initial working diagnosis of infection/sepsis was considered, and antimicrobial treatment was commenced.Development of dyspnea and reduced right basal air entry prompted chest radiography, which demonstrated a right-sided pleural effusion.Congestive cardiac failure was initially considered; however, the reported Nterminal pro-B-type natriuretic peptide (NT-proBNP) level was not supportive of heart failure.Further laboratory evaluation demonstrated an alkaline phosphatase of 307 U/L, bilirubin of 21 micromol/L, and albumin of 31 g/L.These findings, combined with persistent fatigue and a new pleural effusion, prompted diagnostic re-evaluation.Urgent computed tomography of the chest, abdomen, and pelvis demonstrated extensive ill-defined liver lesions and abnormal gallbladder findings concerning for metastatic malignancy.Hepatopancreatobiliary multidisciplinary team review subsequently determined the disease to represent an unresectable gallbladder primary with metastatic involvement, and management was redirected toward palliative and supportive care.This case highlights the hazards of anchoring bias and premature closure when chronic symptoms are attributed to an established diagnosis.Persistent fatigue should remain an active clinical problem rather than being retrospectively incorporated into a pre-existing diagnosis without reassessment.In older adults, abnormal liver blood tests and an unexplained pleural effusion should prompt reconsideration of occult malignancy, particularly when the overall clinical trajectory is discordant with the initial diagnosis.