The Abscess That Was Cancer: Pyogenic Liver Abscess as the Initial Manifestation of Hepatocellular Carcinoma in a...

Malignant and benign hepatic diseases may both present with systemic symptoms and necrotic liver cavities. Although rare and reported predominantly in East Asia, pyogenic liver abscess (PLA) can represent the initial manifestation of hepatocellular carcinoma (HCC), as necrotic tumors may mimic infectious abscesses.

A 63-year-old Italian man presented with a 2-week history of fever and right upper quadrant pain. Computed tomography revealed a multiloculated lesion with irregular margins and a solid component in the right hepatic lobe, suggestive of a liver abscess, and empirical tigecycline therapy was initiated. Low-titer Entamoeba spp. IgG antibodies were detected, and percutaneous aspiration yielded material initially mischaracterized as "anchovy paste," raising suspicion for amoebic liver abscess. However, the patient failed to improve despite appropriate antiprotozoal therapy. Subsequent percutaneous drainage led to cavity resolution and symptom relief; all microbiological and parasitological tests were negative, and repeat Entamoeba serology became negative. Concurrent biopsy of the solid component revealed well-differentiated pseudoglandular HCC. Magnetic resonance imaging demonstrated a biliary fistula associated with the neoplastic lesion, supporting a diagnosis of PLA secondary to HCC. The patient underwent right hepatectomy, complicated by intraoperative abscess rupture and postoperative intra-abdominal abscesses caused by vancomycin-resistant Enterococcus faecium.

PLA presenting as the initial manifestation of HCC is associated with poor prognosis, largely due to diagnostic delays. Limited clinical experience outside high-prevalence regions and nonspecific clinical, laboratory, and imaging findings contribute to underrecognition of malignancy. Positive microbiological or serological results and transient clinical improvement during antimicrobial therapy do not exclude an underlying neoplasm. Liver biopsy and close radiologic follow-up are essential in atypical or treatment-refractory cases.

PLA as a presenting feature of HCC is unusual, especially in Europe, yet poses substantial diagnostic and therapeutic challenges. Increased clinical awareness and early histopathological evaluation are crucial to avoid delayed oncologic diagnosis.