The Expression of Multiple Proteins as Prognostic Factors in Colorectal Cancer: Cathepsin D, p53, COX-2, Epidermal Growth Factor Receptor, C-erbB-2, and Ki-67

BACKGROUND/AIMS: A single gene mutation alone cannot explain the poor prognosis of colorectal cancer. This study aimed to establish a correlation between the expression of six proteins and the prognosis of colorectal cancer patients. METHODS: Tissue samples were collected from 266 patients who underwent surgery for colorectal cancer at our institution from January 2006 to December 2007. The expression of six proteins were determined using immunohistochemical staining of specimens. RESULTS: Cathepsin D, p53, COX-2, epidermal growth factor receptor, c-erbB-2, and Ki-67 expression were detected in 38.7%, 60.9%, 37.6%, 35.7%, 30.1%, and 74.4% of the samples, respectively. The expression of cathepsin D was significantly correlated with reduced cancer-free survival (p=0.036) and colorectal cancer-specific survival (p=0.003), but the other expression levels were not. In a multivariate analysis, cathepsin D expression was found to be an independent prognostic factor for poorer colorectal cancer-specific survival (hazard ratio, 8.55; 95% confidence interval, 1.07 to 68.49). Furthermore, patients with tumors expressing four or more of the proteins had a significantly decreased cancer-free survival rate (p=0.006) and colorectal cancer-specific survival rate (p=0.002). CONCLUSIONS: Patients with cathepsin D positivity had a poorer outcome than patients who were cathepsin D-negative. Thus, cathepsin D may provide an indicator for appropriate intensive follow-up and adjuvant chemotherapy.

Analysis of Prognosis in Colorectal Mucinous Adenocarcinoma: A Retrospective Analysis with Peritoneal Fluid

PURPOSE: Although many papers have reported poor prognosis of colorectal mucinous adenocarcinoma, the underlying cause for its unfavorable outcome is yet to be elucidated. In the peritoneal fluid studies, we observed that peritoneal recurrences and cytology positive cases were many times mucinous cancers. On the basis of these observations, mucinous and non-mucinous adenocarcinomas were compared and prognostic factors were studied. METHODS: Five hundred and forty-six patients who underwent surgery for colorectal adenocarcinomas from January 2004 to December 2008 were included. RESULTS: Among the 546 patients, mucinous adenocarcinomas were 30 (5.5%) and non-mucinous adenocarcinomas were 516 (94.5%). Mean age was 55.0 years, which was younger than 63.2 years in non-mucinous colon cancers. They tend to develop in the right colon. Mucinous adenocarcinomas were more advanced in depth of invasion and distant metastasis, but no significant difference in lymph node (LN) metastasis. Peritoneal CEA, CA19-9, and positive cytology were more apparent. Liver and peritoneal metastasis did not show significant increases. Five year survival rates were 82.9% and 91.7% and cancer free survival rates were 42.7% and 68.5% each, respectively, for mucinous and non-mucinous cancers. According to stage, only stage III and IV patients showed differences in cancer free survival and overall survival (P=0.001, 0.040). CONCLUSION: Mucinous adenocarcinomas showed worse prognoses and significant differences in recurrences, but had similar prognoses in early cancers. Although no significant differences were in LN metastasis, dissimilarities were in infiltration depth. Infiltrations led to the increase in free cancer cells and peritoneal fluid tumor markers: ultimately cancer recurrences developed.

The Use of Short-term Antimicrobial Prophylaxis in Elective Surgery for Gastric Cancer

PURPOSE: Although most surgeons generally administer prophylactic antibiotics for more than three days, the optimal duration of antimicrobial prophylaxis in elective gastric surgery is still open to debate. The aim of this study was to determine if the duration of prophylactic antibiotic use can affect the recovery of patients after elective gastric surgery. MATERIALS AND METHODS: A total of 93 patients with gastric cancer were enrolled in this study, between January 2007 and December 2007. Patients were excluded if they had an infection at the time of surgery or they underwent an emergency operation. The first antibiotics were commonly given from just prior to the operation. The patients were divided into three groups according to the operation periods: those who received antibiotics only on the day of operation (arm A), those who received antibiotics for up to 3 days (arm B), and those who received antibiotics for more than 5 days postoperatively (arm C). The antibiotic that was used was second generation cephalosporin. RESULTS: The rate of surgical site infection was 12.9% (n=4) in arm A, 16.1% (n=5) in arm B and 19.4% (n=6) in arm C, respectively (P=0.788). No relationship was observed between the duration of prophylaxis and the rate of fever or the neutrophil counts during postoperative 7 days (P=0.119, P=0.855). CONCLUSION: The prophylactic effect of antibiotics on recovery, with the antibiotics being received only on the day of the operation, is as effective as receiving antibiotics for a longer duration after gastric cancer surgery.

Malignant Solitary Fibrous Tumor in the Perianal Region

Solitary fibrous tumors (SFT) are rare spindle-cell neoplasms that are found principally in the pleura, and extrathoracic SFTs are even less common. We report here on a case of malignant solitary fibrous tumor in the perianal region. A 47-year-old man was referred to our hospital for surgical treatment of an incidentally discovered perianal mass. Pelvic MRI showed a slightly lobulated solid mass with central necrosis in the ischiorectal fossa. We performed complete removal of tumor with using a postanal approach. The resected specimen was 6.5x5.0x5.0 cm in size, and it was an elastic solid tumor with invasion to the surrounding muscle structures. Histologically, the tumor was composed of a patternless proliferation of spindle cells with a collagenous matrix and the tumor cells showed increased cellularity, cellular pleomorphism and frequent mitotic figure. Immunohistochemical staining was positive for CD34 and negative for desmin, which indicated malignant SFT. We report here on a rare case of malignant SFT in the perianal region along with a review of the literature.