Toshiro Ogura

Clinicopathological characteristics and prognostic impact of colorectal cancers with NRAS mutations

At present, molecular markers of colorectal cancer (CRC), including KRAS, NRAS and BRAF mutations, and the microsatellite status are evaluated for the development of personalized treatments. However, clinicopathological and molecular characteristics and the prognostic role of NRAS mutations remain unclear. In the present study, a total of 1,304 consecutive stage 0-IV CRC tumor samples were analyzed for KRAS (exon 2, 3 and 4), NRAS (exon 2 and 3) and BRAF (exon 15) mutations. Multivariate analysis was performed to assess the prognostic impact of NRAS mutations. KRAS, NRAS and BRAF mutations were identified in 553 (42.4%), 35 (2.7%), and 59 (4.5%) of 1,304 CRC cases, respectively. Tumors with NRAS mutations were more frequently located in the distal colorectum compared with those with KRAS or BRAF mutations. Multivariate analysis indicated that KRAS and BRAF mutations were found to be associated with poor prognosis [hazard ratio (HR)=1.44, 95% confidence interval (CI), 1.18-1.76 and HR=2.09; 95% CI, 1.33-3.28, respectively], whereas NRAS mutations were associated with a trend toward favorable prognosis (HR=0.53; 95% CI, 0.27-1.03). Characteristics and prognosis of CRC with NRAS mutations are different from those with KRAS or BRAF mutations.

The RAS mutation status predicts survival in patients undergoing hepatic resection for colorectal liver metastases: The results from a genetic analysis of all-RAS

We investigated the impact of mutations in KRAS exons 3‐4 and NRAS exons 2‐3 in addition to KRAS exon 2, so‐called all‐RAS mutations, in patients with colorectal liver metastasis (CLM) undergoing hepatic resection.

Current topics in the surgical treatments for hepatocellular carcinoma

Treatment strategy for hepatocellular carcinoma (HCC) requires optimal selection of therapies based on various factors related to tumor condition and liver functional reserve. Although several evidence‐based guidelines have been proposed for the treatment of HCC, the criteria and range of indications differ among these guidelines according to the circumstances of each country. In European nations and the USA, patients with the Barcelona Clinic Liver Cancer stage 0‐A are subjects for surgical resection, whereas in Asian countries, even those with the intermediate stage are regarded as surgical candidates. Furthermore, since the recent introduction and rapidly widely spreading use of laparoscopic liver resection, this technique has become an important treatment option for surgical resection. In this review article, we overview the current topics of treatment of HCC with a special focus on surgical therapy.