S5804 Metastasis or Infection: A Rare Case of Liver Abscess Imitating Metastatic Disease in Esophageal Adenocarcinoma

Introduction: Advanced esophageal adenocarcinoma is commonly associated with complications due to local invasion or metastasis, while infections are a less recognized risk. Streptococcus viridans, part of normal oral flora, may become pathogenic in immunocompromised patients and is an unusual but known cause of hepatic abscesses. We present a case of newly diagnosed T3N1M0 distal esophageal adenocarcinoma complicated by sepsis and a hepatic lesion initially suspected to be metastatic, but ultimately diagnosed as a Streptococcus anginosus liver abscess. Case Description/Methods: A 59-year-old man with recently diagnosed distal esophageal adenocarcinoma presented with high-grade fever, loose stools, fatigue, anorexia, and decreased oral intake. On arrival, he was febrile to 102.3°F, tachycardic, and normotensive. Labs showed leukocytosis with neutrophil predominance and elevated procalcitonin. Liver enzymes were normal. No clear infectious source was found; respiratory, urinary, GI panel, and tick-borne disease testing were negative. Empiric broad-spectrum antibiotics were initiated for presumed sepsis. Computed tomography (CT) chest imaging revealed a new 8 × 8 × 9 cm low-attenuation lesion in the liver, absent on PET scan one month earlier. Differential diagnoses included metastasis versus abscess. CT-guided aspiration of the lesion yielded purulent fluid, and both blood and abscess cultures grew Streptococcus anginosus. The patient improved significantly after 4 weeks of intravenous antibiotics. He subsequently began chemoradiotherapy and underwent PEG tube placement. Discussion: Streptococcus anginosus, part of the Streptococcus viridans group, is known for its ability to form abscesses, especially in the liver. It has been linked to GI malignancies, particularly colorectal cancer, where bacterial translocation may occur through compromised mucosa. Though rare, hepatic abscesses have also been associated with esophageal cancer, likely due to mucosal micro-perforations, tumor-related immune suppression, or hematogenous spread. This case emphasize on the importance of broad diagnostic consideration in oncology patients presenting with sepsis and new hepatic lesions. Infections, though less common than metastases, may mimic malignant spread. Early imaging, microbiologic evaluation, and timely drainage are essential to avoid delays in cancer therapy and reduce morbidity.