UC Davis

Objective. To examine our experience with cytology and histology biopsy of the liver and to define methods for improvement of diagnosis of primary liver tumors. Methods. This include retrospective study of 189 biopsies of 185 liver masses for cytological or histological analysis. Patients were subdivided into two groups. Group 1 consisted of 124 suspected metastasis. Group 2 consisted of 61 suspected primary neoplasms. Biopsies were considered positive or equivocal. In equivocal cases, special stains were performed. In Group 2, cases were classified by contrast CT or MRI as to (I) classic HCC, (II) infiltrated HCC, or (Ill) equivocal. Results. Definitive diagnosis was obtained in 117/124 masses (94%) in Group 1, 48/61 masses (79%) in Group 2, and (Ill) equivocal 13 cases in Group II. In two equivocal cases in which special stains were performed, they were reclassified as HCC. In 8/13 cases, CT findings were consistent with HCC. Conclusion. Liver biopsies are useful in obtaining a definitive diagnosis of suspected metastatic liver disease. Biopsy results are less reliable in patients with suspected primary liver tumors. In these situations, strategies can include basing treatment on imaging criteria or use of newer special pathological stains. Advances in Knowledge. Use of newer special immunological stains improves accuracy in definitive diagnosis of primary liver tumors.