Effects of MDR1/P-glycoprotein expression on prognosis in advanced colorectal cancer after surgery.

Resistance to chemotherapeutic agents is a major problem for successful cancer treatment. P-glycoprotein (Pgp), a product of the multidrug resistance (MDR)1 gene expressed in cancer cells, is one of the mechanism of MDR. However, there are few reports regarding the effects of Pgp on prognosis of colorectal cancer (CRC) after surgery. We examined a total of 80 patients (45 males and 35 females with an average age of 69 years) whose CRCs were classified into stage 2-4 and completely resected surgically in our institute between January 1990 and September 1999. To evaluate Pgp expression in CRC, immunohistochemical stain was performed with a monoclonal antibody. Relationships between Pgp expression and clinicopathological variables which may have affected prognosis were evaluated. Survival curves were calculated using the Kaplan-Meier method, and differences were evaluated with the log-rank test. The Cox's proportional hazards model was used in the univariate and multivariate survival analysis. Pgp expression showed a significant correlation with histological differentiation (p=0.023). However, no correlation was observed with gender, tumor location, lymph node metastasis, lymphatic invasion, venous invasion, and cancer stages. Survival rates after surgery tended (p=0.093) to be higher in Pgp (+) than Pgp (-) patients. Pgp was not a significant prognostic factor by univariate analysis and multivariate analysis adjusted for other clinicopathologic variables. Survival rates after surgery tended to be higher in Pgp (+) than Pgp (-) patients and Pgp expression was correlated with histological differentiation of CRC. Thus, a relative resistance of CRC to conventional chemotherapy may be partly caused by Pgp expressed in well or moderately differentiated CRC. However, Pgp expression was not a significant independent prognostic factor in advanced CRC after surgery.

Hepatic undifferentiated (embryonal) sarcoma in an adult: a case report and review of the literature.

Undifferentiated (embryonal) sarcoma of the liver (USL) is a rare malignant tumour with a poor prognosis. The absence of specific symptoms, the rapid tumour growth, the normality of the common tumour markers, and the consequential delay in the diagnosis often result in significant enlargement of the tumour. To our knowledge, there have been only 42 reported cases of USL in adults worldwide during the 40 years since the clinicopathological entity of USL was defined. We report here a 27-year-old male with USL who has been treated successfully with surgical resection and adjuvant chemotherapy using ifosfamide, adriamycin and cisplatin. Although the prognosis of the disease remains generally poor, long-term survival has been achieved recently in patients with a combination of surgery and multi-agent chemotherapy.

Density of Helicobacter pylori infection evaluated semiquantitatively in gastric cancer.

Helicobacter pylori infection may play a role in the development of gastric cancer; however, a quantitative evaluation of the density of H. pylori infection has not been reported previously in relation to the histologic stage and type of cancer. This study was designed to compare the density of H. pylori infection to the histologic stage and type of gastric cancer. Between March 1996 and March 1998, surgical resection of primary lesion was performed in 50 patients with gastric cancer (39 men and 11 women with a mean age of 67 years) at our institution. Using immunohistochemical stains, the density of H. pylori infection was evaluated semiquantitatively at cancer site as well as noncancerous mucosa adjacent to cancer. This density was compared with the histologic stage and the type of gastric cancer. The severity of the mucosal atrophy was evaluated using the updated Sydney System. The prevalences and density of H. pylori infection decreased in proportion to advances in the cancer stage and the mucosal atrophy. In early cancer of the intestinal- and diffuse-type, the prevalence of H. pylori in adjacent sites was almost 90% and was significantly higher (p < 0.01) than that seen in the advanced cancer lesions. In the intestinal-type early cancer, the prevalence and density of infection was higher (p < 0.05) in the adjacent mucosa than in the cancer site, whereas in the diffuse-type early cancer, H. pylori was found in all cases at the cancer site and the adjacent site. In advanced cancer, the prevalence of H. pylori was about 40% in the adjacent site and about 10% in the cancer site in both histologic types. These figures were significantly lower (p < 0.01) than in the early cancers. The prevalence and density of infection did not differ in the intestinal- and diffuse-type gastric cancers, but did decrease with more advanced cancer stages. The changes in local environment of the advanced cancer may not be conducive to the survival of H. pylori. Thus, the prevalence of H. pylori may be affected by the histologic stage rather than the histologic type of gastric cancer, and the organism may play a similar role, but through different pathways, in the pathogenesis of both types of cancer.