In the treatment of advanced metastatic colorectal cancer, several new agents, such as irinotecan and oxaliplatin, have been developed, which have improved both disease free and overall survivals. Among these agents, 5-fluorouracil (5-FU) still remains one of the most active agents, and the selection of patients who can benefit from 5-FU-based chemotherapy is still important, as those unlikely to benefit could be spared the harmful side effects. The expression levels of thymidylate synthase (TS), thymidine phosphorylase (TP) and p53 have been known to be associated with the clinical response to 5-FU-based therapy as well as the prognosis, and that of vascular endothelial growth factor (VEGF) is associated with poor survival.

The relationship between the expressions of TS, TP, VEGF and p53 in primary tumors, using immunohistochemistry, and the response of 45 metastatic colorectal cancer patients (M:F=25:20, median age 59 yrs) to 5-FU-based chemotherapy were evaluated.

Thirty-seven patients were treated with 5-FU/LV/irinotecan (FOLFIRI) and 8 with 5-FU/LV/oxaplatin (FOLFOX). The overall response rate was 28.9% (13/45). When immunohistochemically analyzed with monoclonal antibodies against TS, TP, VEGF and p53, 55.6% of the patients (25/45) were positive for TS, 48.9% (22/45) for TP, 82.2% (37/45) for VEGF, and 80% (36/45) for p53. There was a significant difference in the intensity of TS expression between the clinical responders and non-responders (p=0.036). In terms of the staining pattern of TS expression, diffuse staining was correlated with a poor response (p=0.012) and poor survival (p=0.045). However, there was no correlation between the expressions of TP, VEGF or P53 and the response to chemotherapy.

These results suggest that the expression of TS in primary colorectal cancer might be an important prognostic factor for chemotherapy response and survival, and might be a useful therapeutic marker for the response of chemotherapy.

The purpose of this study was to assess the efficacy and toxicity of biweekly irinotecan plus 5-fluorouracil (FU) and leucovorin (LV) in patients with relapsed or metastatic colorectal cancer.

Between March 2002 and May 2004, 24 patients with histologically confirmed relapsed or metastatic colorectal cancer were enrolled in this study. One chemotherapy cycle consisted of irinotecan 180 mg/m² on days 1 and 15; 5-FU 400 mg/m² bolus IV with 600 mg/m² by a 22 hour intravenous infusion on days 1, 2, 15 and 16; and leucovorin 20 mg/m² on days 1, 2, 15 and 16, every 4 weeks.

The median age of the 24 was 57.5 years (range, 38~69). Their metastatic sites included: the liver (62.5%), lung (20.8%), peritoneum (16.7%), lymph node (12.5%), ovary (8.3%) and pelvis/vagina (8.3%). Twenty-two patients were evaluable for a response. Six and 7 patients achieved partial responses and stable diseases, respectively. The overall response rate was 27.3% (95% Confidence interval; 10.3~44.5%). The median follow-up duration for surviving patients was 14.7 months (range, 1.7~26.5). Median overall survival (OS) and 1-year OS rates were 19 months and 86.3%, respectively. Median response duration and median progression free survival were 7.47 and 5.57 months, respectively. A total of 83 cycles (median 4 cycles) were administered. The main non-hematologic toxicities were nausea/vomiting (44.5%/18.1%) and diarrhea (8.4%). The most common hematologic toxicity was NCI grade I/II anemia (31.3%) and grade I/II neutropenia was 10.8%. There was no life-threatening toxicity.

The results suggested that irinotecan, 5-FU and leucovorin combination chemotherapy in a biweekly schedule is a practical and tolerable treatment option in patients with advanced colorectal cancer.

To evaluate the efficacy and toxicity of heptaplatin, paclitaxel, and 5-fluorouracil combination chemotherapy in patients with advanced gastric cancer.

Between July 2002 and September 2003, nineteen patients were enrolled in this study. Paclitaxel 135 mg/m² iv on day 1, heptaplatin 400 mg/m² iv on day 2 and 5-fluorouracil 800 mg/m² on day 2~4 were administered and the regimen was repeated every 3 weeks.

The median age of the patients was 60 years (range: 32~74) and the most common sites of metastasis were liver and lymph nodes. In the 16 evaluated patients, the overall response rate was 43.8%, but this was without any complete response. The median time to disease progression was 3.93 months (range: 0.26~8.1) and the median response duration for the 7 responding patients was 3.83 months (range: 1.48~6.07). The median overall survival for 19 patients was 7.01 months (range: 0.26~17.44). A median of 3 cycles (range: 1~7) and a total of 65 cycles were administered and evaluated for toxicity. The most common hematologic toxicities were NCI grade I/II anemia (47.7%), neutropenia (9.2%) and thrombocytopenia (6.2%). The most common non-hematologic toxicities more than grade II were nausea/vomiting (30.8%/9.2%). One elderly patient with ECOG 2 had a life-threatening complication of pneumonia.

The combination of heptaplatin, paclitaxel, and 5-fluorouracil showed significant activity and favorable toxicity profiles in patients with advanced gastric cancer. However, one elderly patient who had poor performance experienced a life-threatening toxicity/complication. Our results suggest that the efficacy of this combination chemotherapy can be maximized when administered to the patients with good performance status. Further studies with large numbers of patients and long-term follow-up study will be needed.

The purpose of this study was to assess the efficacy and safety of radiofrequency ablation (RFA) to treat hepatic metastasis in patients with colorectal carcinoma.

Between May 1999 and July 2002, a total of 45 tumors in 24 patients with colorectal cancer were treated with RFA. Thirteen patients received systemic chemotherapy after the RFA procedure. The ablation was performed percutaneously under ultrasound guidance using cool-tip or expandable electrodes and an RF generator. The medical records as well as the CT scan results taken every 3 months were retrospectively reviewed.

The median follow-up duration of the surviving patients was 11.7 months (4.6~32.2 months). Complete tumor necrosis was achieved in 17 patients (70.8%) on an immediate (<24 hrs) CT scan. The median survival was 17.1 months. The 1- and 2-year survival rates were 80.5 and 25.8%, respectively. In a univariate analysis, complete necrosis, tumor size and post-RFA chemotherapy were significant factors for survival. Nineteen of the 24 patients developed a recurrence or progressed (79.2%). The median progression free survival was 5.5 months. There were no treatment related deaths or serious adverse effects, with the exception of one case of respiratory failure.

These results suggest that RFA is a well-tolerated and effective method to treat hepatic metastasis in colorectal carcinomas.