The blood supplies of nodular lesions associated with liver cirrhosis were analyzed in vivo with various imaging modalities. The portal blood supply was evaluated with computed tomography (CT) during arterial portography (CTAP); the arterial blood supply was evaluated with hepatic angiography, CT angiography, CT following intraarterial injection of iodized oil, or ultrasound following intraarterial injection of carbon dioxide microbubbles. A total of 84 surgically confirmed hepatocellular carcinomas (HCCs) (less than or equal to 3 cm) and 25 areas of adenomatous hyperplasia (AH) were included in the study. At CTAP, a portal blood supply was seen in 96% of cases of AH and only 6% of HCCs (chi 2, P less than .005). In contrast, an arterial supply greater than that of the surrounding liver was verified in 94% of the HCCs and only 4% of the cases of AH (chi 2, P less than .005). The blood supply of areas of AH with atypical hepatocytes and the blood supply of well-differentiated HCCs (Edmondson grade 1) tended to be intermediate between that of AH without atypia and that of HCC that was Edmondson and Steiner grade 2 or greater. Evaluation of the blood supply of the nodular lesions associated with liver cirrhosis is considered to be useful in the differential diagnosis and treatment of early-stage HCC.

Oral lichen planus (OLP) is a common oral disorder that manifests a mucosal reaction to a variety of aetiological factors, including liver disorder. This study investigated the relationship between OLP and hepatitis C virus (HCV) infection by studying the prevalence of hepatitis B and C virus infection or liver disease in 45 patients with OLP in the Northern Kyushu region of Japan where the prevalence of HCV infection is the highest in the country. Serum hepatitis B virus surface antigen (HBsAg) was positive in only four patients. Serum anti-HCV or serum HCV RNA was positive in 28 (62%) and 27 (60%) of 45 OLP patients, respectively. The majority (35 of 45, 78%) of OLP patients suffered from liver disease, including chronic hepatitis C (22/45, 49%), HCV-related liver cirrhosis (two), and HCV-related hepatocellular carcinoma (two). These results suggest that HCV is a major cause of OLP.

Hepatitis C virus (HCV) infection not only causes chronic liver diseases but shows extrahepatic manifestations as oral lichen planus (OLP) and oral cancer. To elucidate the direct relationships among these diseases and HCV infection, we investigated the detection of positive- and negative-strand HCV-RNA from serum, OLP (n=19), and oral cancer (n=17) tissues. We used a sensitive reverse transcription to polymerase chain reaction (RT-PCR) method, and analyzed sequences from the HCV El/E2 region of the genome from serum and tissue. Positive and negative HCV-RNA strands were observed in 13 (92.9%) and 3 (21.4%) OLP tissues, respectively. In oral cancer tissues, positive HCV-RNA strands were detected in all tissues from anti-HCV positive patients. Negative HCV-RNA strands were observed in 5 of 7 (71.4%) patient's tissues. Furthermore, it was confirmed that the sequence from one of each OLP and oral cancer patient differed between serum and tissue HCV-RNA. These results may indicate that HCV persists and replicates in these lesions, suggesting a pathological role for HCV, although the mechanisms are unclear.

To investigate the effect of matrix-degrading enzymes on the malignant potential of oral squamous cell carcinoma, the expression of matrix metalloproteinase-2 (MMP-2/72-kD gelatinase/type IV collagenase) in 46 patients who had neck surgery for oral cancer was studied immunohistochemically. In 20 of 26 patients (76.9%) with lymph node metastases, proMMP-2 was strongly expressed, whereas the production of proMMP-2 in tissue was detected only in 5 of 20 patients (25%) who had no lymph node metastases. In tissue specimens, proMMP-2 was expressed in a diffuse invasive mode and in the advancing front of cancer. Because MMP-2 can degrade type IV collagen composed of basement membrane, these results suggest that the in vivo production of the enzyme by cancer is an indicator of the degree of malignancy, and that the analysis of proMMP-2 expression is useful to evaluate the malignant potential in individual oral squamous cell carcinoma.

Differentiation of hepatocellular carcinomas from adenomatous hyperplastic nodules (AHNs) is important for the early and precise detection of hepatocellular carcinoma in the cirrhotic liver. For this purpose, the authors compared findings on magnetic resonance (MR) images of surgically resected AHNs (n = 7) with those of hepatocellular carcinoma (n = 47). AHNs were divided into two histologic groups: those without atypia (n = 5) and those with atypical hepatocytes or malignant foci (n = 2). All AHNs without atypia were hyperintense on T1-weighted spin-echo images and hypointense on T2-weighted spin-echo images relative to the surrounding liver. However, almost all hepatocellular carcinomas, except for two lesions with massive coagulation necrosis, were demonstrated as hyperintense on T2-weighted images. MR imaging may be useful in the differentiation of AHN without atypia from hepatocellular carcinoma in the cirrhotic liver.