Jen-Kou Lin

PURPOSE: Preoperative combined chemoradiotherapy is currently the main neoadjuvant therapy used to treat locally advanced middle and low rectal adenocarcinoma. A restaging work-up with magnetic resonance imaging was hoped to provide information about the effects related to combined chemoradiotherapy. The goal was to evaluate the correlation between pathologically verified tumor stages and clinical stages predicted by magnetic resonance imaging after combined chemoradiotherapy. METHODS: Between August 2000 and June 2003, 50 patients with biopsy-proven middle and lower rectal adenocarcinoma, with initial stage T3-T4 or N+, M0, were recruited in this series. Pelvic magnetic resonance imaging was used to stage the tumor before and after combined chemoradiotherapy. A protocol of the standard external radiation dose and oral combined uracil and 5-fluorouracil plus leucovorin was used. The results of magnetic resonance imaging restaging after combined chemoradiotherapy were correlated with the pathologic staging. RESULTS: The overall predictive accuracy in T stage was 52 percent, whereas overstaging and understaging occurred in 38 percent and 10 percent of patients, respectively. Most of the inaccurate T staging was a result of the overstaging of superficial tumors (T0-T2). In N stage, accurate staging was noted in 68 percent of all patients, whereas 24 percent were overstaged and 8 percent were understaged. CONCLUSION: In restaging irradiated tumors, magnetic resonance imaging had the accuracy of 52 percent in T stage and 68 percent in N stage. Poor agreement between post-combined chemoradiotherapy magnetic resonance imaging and pathologic staging was observed in both T (k = 0.017) and N (k = 0.031) stages. Most of the inaccuracy in both T and N stages was caused by overstaging. The problem with magnetic resonance imaging was believed to be that it could not completely differentiate fibrosis from viable residual tumors.

Oxaliplatin is effective in the treatment of metastatic colorectal cancer (MCRC) patients; however, severe neurotoxicity develops frequently. To assess the efficacy of oral glutamine for preventing neuropathy induced by oxaliplatin, a pilot study was performed. A total of 86 patients with MCRC treated at Taipei Veterans General Hospital were enrolled. Oxaliplatin (85 mg/m(2), days 1 and 15) plus weekly bolus 5-fluorouracil (5-FU; 500 mg/m(2)) and folinic acid (FA; 20 mg/m(2)) on days 1, 8, and 15 were given every 28 days as first-line treatment. Patients were randomized to receive (glutamine group; n = 42) or not receive (control group; n = 44) glutamine (15 g twice a day for seven consecutive days every 2 weeks starting on the day of oxaliplatin infusion). Efficacy of chemotherapy, neurological toxicity, and electrophysiological alterations were assessed. A lower percentage of grade 1-2 peripheral neuropathy was observed in the glutamine group (16.7% versus 38.6%) after two cycles of treatment, and a significantly lower incidence of grade 3-4 neuropathy was noted in the glutamine group after four cycles (4.8% versus 18.2%) and six cycles (11.9% versus 31.8%). By adding glutamine, interference with activities of daily living was lower (16.7% versus 40.9%), and need for oxaliplatin dose reduction was lower (7.1% versus 27.3%). There were no significant between-group differences in response to chemotherapy (52.4% versus 47.8%), electrophysiological abnormalities, grade 3-4 non-neurological toxicities (26.2% versus 22.8%), or survival. These data indi-cate that oral glutamine significantly reduces the incidence and severity of peripheral neuropathy of MCRC patients receiving oxaliplatin without affecting response to chemotherapy and survival.

PURPOSE: The features of T1 colorectal adenocarcinoma and the risk determination of lymph node metastasis were reviewed. Prognostic factors were assessed to verify whether the risk of lymph node metastasis would influence the long-term prognosis. METHODS: Patients undergoing curative resection of T1 colorectal adenocarcinoma at the Taipei Veterans General Hospital from December 1969 to August 2002 were retrospectively studied. Patients with synchronous colorectal cancer, distant metastasis, familiar adenomatous polyposis, or inflammatory bowel disease were excluded. The associations between lymph node metastasis and clinicopathologic variables were evaluated univariately using chi-squared test, Fisher's exact test, or Student's t -test, and multivariately using logistic regression. Univariate analysis by the log-rank test and multivariate analysis by Cox regression hazards model determined the factors influencing the overall survival. RESULTS: A total of 159 patients were included. Sixteen patients (10.1 percent) had lymph node metastasis. The risk of lymph node metastasis included histologic grade (P = 0.005), lymphatic vessel invasion (P = 0.023), inflammation around cancer (P = 0.049), and budding at the invasive front of tumor (P = 0.022). Age (P = 0.001) and number of total sampling lymph nodes (P < 0.0001) were found to be the factors influencing the overall survival. CONCLUSIONS: Variables that predict lymph node metastasis in surgically resected T1 colorectal carcinoma may not impact the long-term prognosis.