Routine chest computed tomography as a preoperative work-up for primary colorectal cancer: is there any benefit in short-term outcome?

PURPOSE: The aim of this study was to assess the role of pre-operative chest computed tomography (CT) compared with abdominopelvic CT (AP-CT) and chest radiography (CXR) for detecting pulmonary metastasis in patients with primary colorectal cancer (CRC). METHODS: We retrospectively analyzed the data of 619 patients with primary CRC who simultaneously received a preoperative chest CT (chest CT group), AP-CT with hilar extension, and CXR (CXR group). RESULTS: In the chest CT group, there were 297 (48.0%) normal, 198 (32%) benign, 96 (15.5%) indeterminate, 26 (4.2%) metastasis, and two lung cancers. Eighteen patients (2.9%) in the CXR group who had no pulmonary metastasis were diagnosed with pulmonary metastasis on a chest CT. The sensitivity and accuracy were 83.9% and 99.0% in the chest CT group, respectively, and 29.0% and 91.5% in the CXR group, respectively (P < 0.0001 and P = 0.0003). CONCLUSION: Chest CT appears to improve the accuracy of pre-operative staging in patients with CRC and is useful for the early detection of pulmonary metastasis as a baseline study for abnormal lung nodules.

Narrow distal resection margin may be sufficient for rectal cancer after chemoradiation.

BACKGROUND/AIMS: What constitutes an adequate length for the distal resection margin in patients with mid-to-distal rectal cancer after pre-operative chemoradiation therapy (PCRT) continues to be debated. The purpose of the present study was to determine the effect of the distal resection margin on oncological outcome and establish a guideline for the distal resection margin in patients with rectal cancer after PCRT. METHODOLOGY: Data from 204 patients undergoing low anterior resection after completion of chemoradiation therapy were examined. Associations between clinicopathological parameters, including the distal resection margin and oncological outcome, were analyzed retrospectively. RESULTS: The distal resection margin was not significantly associated with local recurrence-free survival, disease-free survival, or overall survival; subgroup analysis of the T3,4 group showed the same results. Further analysis using various lengths (0.5, 1.5, 1 and 2cm) of the resection margin did not show statistical significance for oncological outcomes. Pre-PCRT clinical stage, post-PCRT pathological T stage, and histological grade were significantly associated with disease-free survival. CONCLUSIONS: For patients with locally advanced rectal cancer undergoing resection and pre-operative chemoradiotherapy, a narrow distal resection margin did not compromise oncological outcomes.

Comparison and short-term outcomes between hand-assisted laparoscopic surgery and conventional laparoscopic surgery for anterior resections of left-sided colon cancer.

BACKGROUND: Hand-assisted laparoscopic surgery has been introduced as an alternative to conventional laparoscopic surgery. This study compared the efficacies and short-term clinical outcomes between hand-assisted laparoscopic anterior resection (HAL-AR) and conventional laparoscopic anterior resection (CL-AR) for treating left-sided colon cancer. MATERIALS AND METHODS: We retrospectively analyzed 248 patients who underwent anterior resection for colon cancer (118 HAL-AR and 128 CL-AR) between May 2000 and December 2006. The collected data included the perioperative and short-term oncologic outcomes. RESULTS: There were no significant differences between the HAL-AR and CL-AR groups, except for the operation time and the size of the primary tumor. The operation time of the HAL-AR group was significantly shorter than that of the CL-AR group (p = 0.004), and the size of the primary tumor in the HAL-AR group was significantly larger than that of the CL-AR group (p = 0.019). The operating time of the HAL-AR group reached an earlier mean plateau than did that of the CL-AR group. Before and after reaching the plateau, there were no differences in the perioperative results between the two groups. The operating time for the HAL-AR group was significantly shorter than that of the CL-AR group after reaching a plateau (p = 0.012). The short-term outcomes for both groups were similar in terms of survival and recurrence (p = 0.996 and p = 0.476, respectively). CONCLUSION: Hand-assisted laparoscopic anterior resection has a shorter operative time than does CL-AR and is more successful than CL-AR for resecting larger tumors, while both procedures result in similar short-term oncologic outcomes. Hand-assisted laparoscopic anterior resection is thought be a comparable operative technique for anterior resection of left-sided colon cancer.

Location-related differences in sporadic microsatellite unstable colorectal cancer.

BACKGROUND: Microsatellite unstable CRC is associated with female gender, large tumours, and poor differentiation. However, there are few reports about the characteristics and differences of sporadic microsatellite unstable CRC based on tumour location. AIMS: Site-specific heterogeneity of sporadic microsatellite unstable colorectal cancer (CRC) based on location was elucidated. METHODS: We enrolled 164 CRC patients with high-frequency microsatellite instability (MSI-H) from the prospective database of 2686 consecutive CRC patients who underwent surgical resection. We analysed microsatellite instability (MSI) and expression of mismatch repair (MMR) proteins (MLH1, MSH2, and MSH6). RESULTS: Among the 164 MSI-H CRC, 105 (64.0%) were located in the proximal colon and 59 (36.0%) were located in the distal colon. The proximal MSI-H CRC was predominantly in female (p=0.014), had a more aggressive differentiation (p=0.001), was of advanced stage (p=0.035), and had a frequent loss of MLH1 expression (p=0.005) compared to the distal MSI-H CRC. CONCLUSION: There were different clinicopathologic characteristics and MMR protein expression between proximal and distal MSI-H CRC. These findings suggest that the underlying carcinogenic pathway or molecular background differs according to location, despite being microsatellite unstable CRC.