Toshiki Kamano

Comparison of stent placement and colostomy as palliative treatment for inoperable malignant colorectal obstruction

BackgroundStent placement is a useful palliative treatment for inoperable acute malignant colorectal obstruction. However, data comparing stent placement with colostomy are scarce.MethodsWe compared the clinical outcome of 18 patients who had stent placement and 17 patients who underwent only colostomy.ResultsThe postoperative hospital stay was 22.3 days for stent placement compared with 47.4 days for colostomy (p = 0.016). The duration to readmission was 129.2 days for stent placement and 188.4 days for colostomy. The estimated duration of primary stent patency was 106 days. Mean survival period was 134 days in patients with stent placement and 191 days in patients with colostomy.ConclusionPostoperative hospital stay was shorter in patients with stent placement but duration to readmission and survival were longer in patients with colostomy. However, stent placement increases the option of palliative treatment and is an effective treatment contributing to improving quality of life.

Early ductal lesions of pancreatic carcinogenesis in animals and humans

SummaryTwo cases of human early pancreatic duct adenocarcinoma were presented, and ductal lesions observed histologically were compared to those induced in hamsters using a rapid-production model of pancreatic carcinoma. In human cases, direct histologic evidence was obtained to suggest that cancerous changes arose from duct epithelial cell hyperplasia, because lesions of hyperplasia and carcinoma coexisted in continuity. In hamster serialkilling studies, it was suggested that carcinoma developed through atypical ductal hyperplasia.

A case of fibromatosis of the breast.

A 36-year-old woman presented with a 10 mm diameter mass in the right breast. Since the mass persisted for 3 months after detection and mammary carcinoma was suspected based on ultrasonographic findings, the mass was resected. Histologically, the mass demonstrated proliferative margins and consisted of spindle cells with bland cytologic features and abundant collagen. Immunohistochemically, the spindle cells were positive for vimentin and smooth muscle actin, and were negative for cytokeratins and desmin. Furthermore, the cells showed MIB-1 immunoreactivity with a MIB-1 labeling index of 4.1. Based on these findings, was diagnosed fibromatosis. Breast fibromatosis is rare and is usually misdiagnosed as breast carcinoma preoperatively. To date, only 10 cases of breast fibromatosis have been reported in Japan. Among the reported cases in Japan, our patient presented with the smallest mass, and ultrasonographic findings in this case were the same as those of other cases. Our experience and a review of the literature indicated that differentiation of fibromatosis from carcinoma is very dificult by ultrasonographic examination. In our case, despite involvement of the surgical margins, there was no recurrence. This may be attributed to the small size of the mass and focal exposure.

Activated peritoneal macrophages inhibit the proliferation of rat ascites hepatoma AH-130 cells via the production of tumor necrosis factor-α and nitric oxide

Abstract:Objective: To study the effect of peritoneal macrophages on tumor cell proliferation, we cultured ascites hepatoma AH-130 cells with unstimulated, or lipopolysaccharide (LPS)- or interleukin (IL)-2-stimulated rat peritoneal macrophages, and examined the proliferation of AH-130 cells.¶Materials and Methods: Rat peritoneal macrophages isolated from male Wistar rats were co-cultured with AH-130 cells in the absence or presence of LPS or IL-2. After incubation, proliferation of AH-130 cells was analyzed using flow cytometry. In addition, the levels of tumor necrosis factor (TNF)-α and nitric oxide (NOx, nitrate + nitrite) in the culture supernatants were measured. Furthermore, anti-TNF-α antibody (10 μg/ml) and nitric oxide synthase inhibitor, NG-monomethyl-L-arginine (L-NMMA, 100 μM) were added to the co-culture, and their effect on AH-130 cell proliferation was examined.¶Results: When AH-130 cells were co-cultured with unstimulated peritoneal macrophages, proliferation of AH-130 cells was not affected. In contrast, when AH-130 cells were co-cultured with peritoneal macrophages in the presence of LPS (0.1-20 μg/ml) or IL-2 (1-200 U/ml), proliferation of AH-130 cells was dose-dependently suppressed by LPS or IL-2. Moreover, LPS- or IL-2-stimulation increased the levels of TNF-α and NOx in the supernatants of AH-130 cell and macrophage co-culture, although LPS and IL-2 did not induce TNF-α and NOx production by AH-130 cells incubated without macrophages. Interestingly, anti-TNF-α antibody and L-NMMA significantly inhibited the suppression of AH-130 cell proliferation by LPS- or IL-2-stimulated macrophages (p<0.05). Furthermore, exogenously added recombinant rat TNF-α (0.26-1300 ng/ml) or NO donor (GSNO, S-nitroso-L-glutathione) (0.1-10 mM) dose-dependently suppressed the proliferation of AH-130 cells in the absence of macrophages.¶Conclusion: Together these observations suggest that when peritoneal macrophages are activated by LPS and IL-2, they suppress the proliferation of ascites hepatoma AH-130 cells via the production of TNF-α and nitric oxide.¶

Ratio of primary and secondary bile acids in feces

PURPOSE: Increases in fecal bile acids may play a role in colorectal carcinogenesis. The authors tested the hypothesis that high concentrations of primary and secondary bile acids are more common in patients with colon cancer than in patients with other gastrointestinal diseases. METHODS: In this retrospective study the secondary bile acid deoxycholic acid and the primary bile acid cholic acid were measured in the feces by enzyme-linked immunoabsorbent assay in 63 patients with colorectal cancer, 24 patients with gastric cancer, 11 patients with biliary disorders, and 47 healthy volunteers. RESULTS: Preoperatively, the mean deoxycholic acid values tended to be higher and the cholic acid values were significantly lower in patients with colorectal cancer than in healthy subjects. Patients with other gastrointestinal diseases had lower deoxycholic acid and cholic acid values than healthy subjects. In healthy subjects the deoxycholic acid to cholic acid ratio ranged from 0.10 to 2.86 (mean, 0.88), but in almost two-thirds, the ratio did not exceed 1. In contrast, the mean preoperative ratio in patients with colorectal cancer was 2.26 (range, 0.06–7.17;P<0.0001) and tended to be higher in patients with advanced cancer and in those with sigmoid and rectal tumors. If 1.1 is taken as the upper limit of normal for deoxycholic acid to cholic acid ratio, 67 percent of patients with colorectal cancer had an abnormal value preoperatively. CONCLUSION: A high deoxycholic acid concentration and deoxycholic acid to cholic acid ratio may be indicators of colorectal cancer. Further study is needed to improve sensitivity and specificity, perhaps by combining fecal bile acid measurements with other tests, and a large prospective trial may be warranted to determine whether these measurements have value in screening for this common cancer.

Abdominal Wound Dehiscence in Patients Receiving Long-term Steroid Treatment

Steroids inhibit primary wound healing and delay the formation of granulation tissue, but it has been controversial whether long-term steroid treatment by itself increases the risk of abdominal wound dehiscence. The aim of this study was to determine whether the pre-operative dose and post-operative total dose of steroids influence abdominal wound dehiscence. Of 28 patients who had surgery while receiving long-term steroid treatment, seven had abdominal wound dehiscence and 21 did not have dehiscence. The two groups differed significantly in the post-operative dose of steroids (404.3 ± 147.1 and 135.6 ± 118.7 mg, respectively) and the duration of wound healing (57.3 ± 18.0 and 12.4 ± 3.8 days), but no other differences were found. Abdominal wound dehiscence may be influenced by the post-operative rather than the pre-operative steroid dose.

Colonic carcinoma resembling submucosal tumor: report of a case and review of the literature.

Submucosal tumor-like colorectal carcinoma, most of whose surface is covered with normal mucosa, is very rare. We report a case of colonic carcinoma resembling submucosal tumor. A 54-yr-old man visited our institution for an evaluation of a positive fecal occult blood test. Colonoscopic examination revealed a small, mainly red polypoid lesion with a central deep ulceration and many white spots in the sigmoid colon. Indigocarmine staining demonstrated that the white spots were faint shallow depressions. Magnifying colonoscopic examination showed that the lesion surface, except for the ulceration and the depressions, was covered with normal mucosa. Although the tumor was small, we strongly suspected its malignancy due to a deep ulceration. As we could not excise it endoscopically, we performed sigmoidectomy. The lesion was 12 mm in size. Histologic examination revealed that the lesion was a moderately differentiated adenocarcinoma that was mainly covered with normal mucosa, that carcinoma was exposed only at the ulceration and the depressions on the surface, and that it had expanded to the muscularis propria. Together with considerations from the literature, this type of colorectal carcinoma is supposed to be invasive and surgical resection should be considered, no matter how small it may be.

Analysis of the Relationship between Sex and Chromosomal Aberrations in Colorectal Cancer by Comparative Genomic Hybridization

Colorectal cancer is thought to be more common in men than in women. The chromosomal locations of DNA gains and losses in surgical specimens of colorectal tumours were detected by comparative genomic hybridization and were compared by gender. Five chromosomal regions, 7p, 8p, 8q, Xp and Xq, contained multiple gains that were significantly more common in males than in females, and within these regions, the differences were significant for Xp21, Xp11.3, Xp11.4 and Xq26. Regions 1p, 3q, 11q, 12p, 12q and 15q contained multiple sites of gain that were significantly more common in females than in males. Tumours from male and female patients showed significantly more losses at 11p and 15q, and at 4q and Xq, respectively. The fact that gains in X-chromosomal regions were detected with a significantly higher frequency in tumours from male patients suggests that the difference between the genders might be explained by X-chromosomal inactivation.

Laparoscopic cholecystectomy after coronary artery bypass grafting using the right gastroepiploic artery: Report of a case

Abstract.A laparoscopic cholecystectomy (LC) was successfully performed on a 61-year-old man who had undergone coronary artery bypass grafting (CABG) using the right gastroepiploic artery (RGEA). He complained of right hypochondralgia 20 days after CABG. Gallstones were diagnosed and a cholecystectomy was performed 9 months after CABG. Under general anesthesia, the operation was performed using a pneumoperitonium. When a laparoscope was inserted, the RGEA pedicle could be clearly recognized. The pedicle obstructed the operating field and made the working space narrower than usual. No ST changes on the electrocardiogram were seen during LC, especially during the initiation of pneumoperitonium, the insertion of the ports, or when retracting the gallbladder. The postoperative course was uneventful. To avoid complications, care should be taken not to stretch the RGEA pedicle during LC, and careful monitoring of the electrocardiogram is also necessary. It is difficult to view the operating field and the RGEA pedicle together. It is therefore better to insert another laparoscope for concomitant monitoring of the RGEA pedicle.

Greater development of 1,2-dimethylhydrazine-induced colon cancer in a rat model of type 2 diabetes mellitus

Several clinical cohort and case-control studies have suggested a link between diabetes and colon cancer. Otsuka Long-Evans Tokushima Fat (OLETF) rats spontaneously develop type 2 diabetes mellitus and Long-Evans Tokushima Otsuka (LETO) rats are non-diabetic. The relationship between type 2 diabetes mellitus and colon cancer was examined in these rats. The carcinogen 1, 2-dimethylhydrazine was administered subcutaneously once weekly for 10 weeks, and the animals were killed and necropsied in week 29. All OLETF rats and 80% of the LETO rats developed cancer. The number of colon cancers per rat was significantly greater in the diabetic than in the non-diabetic rats. Although the tumours tended to be larger in diabetic rats, the difference was not statistically significant. No significant differences were observed in the depth of invasion or histological type of cancer in the two groups. Type 2 diabetes mellitus may enhance the generation and growth of colon cancer.