Clinical significance of subcellular localization of KL-6 mucin in primary colorectal adenocarcinoma and metastatic tissues

AIM： To assess subcellular localization of KL-6 mucin and its clinicopathological significance in colorectal carcinoma as well as metastatic lymph node and liver tissues. METHODS： Colorectal carcinoma tissues as well as metastatic lymph node and liver tissues were collected from 82 patients who underwent colorectomy or hepatectomy. Tissues were subjected to immunohistochemical analysis using KL-6 antibody. RESULTS： Of the 82 colorectal carcinoma patients, 6 showed no staining, 29 showed positive staining only in the apical membrane, and 47 showed positive staining in the circumferential membrane and/or cytoplasm. Positive staining was not observed in non-cancerous colorectal epithelial cells surrounding the tumor tissues. The five-year survival rate was significantly lower in cases showing positive staining in the circumferential membrane and/or cytoplasm （63.0%） than those showing positive staining only in the apical membrane （85.7%） and those showing no staining （100%）. Statistical analysis between clinicopathological factors and subcellular localization of KL-6 mucin showed that KL-6 localization in the circumferential membrane and/or cytoplasm was significantly associated with the presence of venous invasion （P = 0.0003）, lymphatic invasion （P 〈 0.0001）, lymph node metastasis （P〈0.0001）, liver metastasis （P = 0.058）, and advanced histological stage （P〈 0.0001）. Positive staining was observed in all metastatic lesions tested as well as in the primary colorectal carcinoma tissues. CONCLUSION： The subcellular staining pattern of KL-6 in colorectal adenocarcinoma may be an important indicator for unfavorable behaviors such as lymph node and liver metastasis, as well as for the prognosis of patients.

Surgical approach for hepatitis C virus-related hepatocellular carcinoma

Hepatitis C is a strong prognostic factor for patients with hepatocellular carcinoma(HCC). Although liver resection and liver transplantation offer the chance of a cure for HCC,adequate management of co-existing infection with hepatitis C virus(HCV) is important to enable better long-term outcomes after surgery for HCV-related HCC. For patients undergoing liver resection,perioperative anti-viral treatment is recommended,since a decreased HCV viral load itself is reportedly associated with a lower tumor recurrence rate and a longer overall survival. For patients undergoing transplanatations for HCC complicated by end-stage liver disease,the post-transplant management of HCV infection is also necessary to prevent progressive graft injury caused by active hepatitis under the immunosuppressive condition that is needed after liver transplantation. Although only a few lines of solid evidence are available for postoperative antiviral treatment because of the limited indication and frequent adverse events caused by conventional high-dose combination interferon therapy,new direct acting anti-viral agents would enable interferon-free anti-viral treatment with a higher virologic response and minimal side effects.

Stratification of risk of recurrence after curative-intent treatment for small hepatocellular carcinoma

For patients with preserved liver function,tumor number and size have conventionally been main criteria for selecting optimal treatment for hepatocellular carcinoma(HCC)(1,2).Particularly for the group of patients with small(≤3 cm)HCC,there have been aggressive discussions regarding the superiority of surgery vs.ablation therapies(3)because this group of patients may enjoy long-term survival with an adequate curative-intent treatment.