US, CT, AND MRI OF PRIMARY AND SECONDARY LIVER LYMPHOMA

Objective: To describe the imaging findings in patients with pathologically proven hepatic lymphoma. Materials and Methods: Ultrasound, CT, and MRI studies in 23 patients with primary (11 patients) or secondary (12 patients) liver lymphoma were retrospectively reviewed. All patients had proven non-Hodgkin lymphoma; all imaging studies were obtained within 3 weeks of biopsy. Results: No finding or group of findings was specific for the diagnosis of hepatic lymphoma. In 7 of 11 cases of primary lymphoma, a single well-defined lesion was seen. Secondary liver lymphoma occurred as multiple (8 of 12) or diffusely infiltrating lesions (3 of 12) in most cases; it appeared as a solitary lesion in only 1 case. When discrete focal lesions were identified, the lesions were hypo- to anechoic on ultrasound, hypodense on CT, and had low and high signal intensity on T1- and T2-weighted MRI, respectively. Conclusion: Although no one finding appears to be diagnostic of hepatic lymphoma, ultrasound that demonstrates a homogeneous, hypoechoic, through-transmitting lesion combined with CT that demonstrates a solid, low attenuation lesion is highly suggestive of primary liver lymphoma. Secondary liver lymphoma can have a greater variety of appearances and is more likely to be multiple or diffusely infiltrating lesions than a solitary lesion.