Accuracy of computed tomography in nodal staging of colon cancer patients

AIM: To predict node-positive disease in colon cancer using computed tomography(CT).METHODS: American Joint Committee on Cancer stage Ⅰ-Ⅲ colon cancer patients who underwent curavtiveintent colectomy between 2007-2010 were identified at a single comprehensive cancer center. All patients had preoperative CT scans with original radiology reports from referring institutions. CT images underwent blinded secondary review by a surgeon and a dedicated abdominal radiologist at our institution to identify pericolonic lymph nodes(LNs). Comparison of outside CT reports to our independent imaging review was performed in order to highlight differences in detection in actual clinical practice. CT reviews were compared with final pathology. Results of the outside radiologist review, secondary radiologist review, and surgeon review were compared with the final pathologic exam to determine sensitivity, specificity, positive and negative predictive values, false positive and negative rates, and accuracy of each review. Exclusion criteria included evidenceof metastatic disease on CT, rectal or appendiceal involvement, or absence of accompanying imaging from referring institutions.RESULTS: From 2007 to 2010, 64 stageⅠ-Ⅲ colon cancer patients met the eligibility criteria of our study. The mean age of the cohort was 68 years, and 26(41%) patients were male and 38(59%) patients were female. On final pathology, 26 of 64(40.6%) patients had nodepositive(LN+) disease and 38 of 64(59.4%) patients had node-negative(LN-) disease. Outside radiologic review demonstrated sensitivity of 54%(14 of 26 patients) and specificity of 66%(25 of 38 patients) in predicting LN+ disease, whereas secondary radiologist review demonstrated 88%(23 of 26) sensitivity and 58%(22 of 38) specificity. On surgeon review, sensitivity was 69%(18 of 26) with 66% specificity(25 of 38). Secondary radiology review demonstrated the highest accuracy(70%) and the lowest false negative rate(12%), compared to the surgeon review at 67% accuracy and 31% false negative rate and the outside radiology review at 61% accuracy and 46% false negative rate.CONCLUSION: CT LN staging of colon cancer has moderate accuracy, with administration of NCT based on CT potentially resulting in overtreatment. Active search for LN+ may improve sensitivity at the cost of specificity.

与 resectable 在病人化疗和幸存预定胃的腺癌

AIM: To evaluate the timing of chemotherapy in gastric cancer by comparing survival outcomes in treatment groups. METHODS: Patients with surgically resected gastric adenocarcinoma from 1988 to 2006 were identified from the Los Angeles County Cancer Surveillance Program. To evaluate the population most likely to receive and/or benefit from adjunct chemotherapy, inclusion criteria consisted of Stage Ⅱ or Ⅲ gastric cancer patients 】 18 years of age who underwent curative-intentsurgical resection. Patients were categorized into three groups according to the receipt of chemotherapy:(1) no chemotherapy;(2) preoperative chemotherapy; or(3) postoperative chemotherapy. Clinical and pathologic characteristics were compared across the different treatment arms.RESULTS: Of 1518 patients with surgically resected gastric cancer, 327(21.5%) received perioperative chemotherapy. The majority of these 327 patients were male(68%) with a mean age of 61.5 years; and they were significantly younger than non-chemotherapy patients(mean age, 70.7; P 【 0.001). Most patients had tumors frequently located in the distal stomach(34.5%). Preoperative chemotherapy was administered to 11.3% of patients(n = 37) and postoperative therapy to 88.7% of patients(n = 290). An overall survival benefit according to timing of chemotherapy was not observed on univariate or multivariate analysis. Similar results were observed with stagespecific survival analyses(5-year overall survival: Stage Ⅱ, 25% vs 30%, respectively; Stage Ⅲ, 14% vs 11%, respectively). Therefore, our results do not identify a survival advantage for specific timing of chemotherapy in locally advanced gastric cancer. CONCLUSION: This study supports the implementation of a randomized trial comparing the timing of perioperative therapy in patients with locally advanced gastric cancer.