Comparing 5-Year Survival Rates Before and After Re-stratification of Stage I-III Right-Sided Colon Cancer Patients by Establishing the Presence/Absence of Occult Tumor Cells and Lymph Node Metastases in the Different Levels of Surgical Dissection.

BACKGROUND: To establish the impact of re-stratification on the outcomes of patients (stage I-III right-sided colon cancer) based on the presence/absence of occult tumor cells (OTC) and/or metastatic lymph nodes in the different levels of surgical dissection. METHODS: Consecutive patients were drawn from a multicenter prospective trial. After surgery, the surgical specimen was divided into the D1/D2 and D3 volumes before being further analyzed separately. All lymph nodes were examined with cytokeratin CAM 5.2 immunohistochemically. Lymph nodes containing metastases and OTC (micrometastases; isolated tumor cells) were identified. Re-stratification was as follows: RS1, stages I/II, no OTC in D1/D2 and D3 volumes; RS2, stages I/II, OTC in D1/D2 and/or D3; RS3, stage III, lymph node metastases in D1/D2, with/without OTC in D3; RS4, stage III, lymph node metastases in D3, with/without OTC in D3. RESULTS: Eighty-seven patients (39 men, 68.4 + 9.9 years) were included. The standard stratified (SS) group contained the following: stages I/II (SS1) 57 patients; stage III (SS2) 30 patients. Re-stratified (RS) contained RS1 (38), RS2 (19), RS3 (24), and RS4 (6) patients. Lymph node ratio (OTC) RS2: 0.157 D1/D2; 0.035 D3 and 0.092 complete specimens. Lymph node ratio RS3: 0.113 D1/D2; complete specimen 0.056. Overall survival and disease-free survival were p = 0.875 and p = 0.049 for SS and p = 0.144 and p = 0.001 for RS groups, respectively. CONCLUSION: This re-stratification identifies a patient group with poor prognosis (RS4). Removing this group from SS2 eliminates all the differences in survival between RS2 and RS3 groups. The level of dissection of the affected nodes may have an impact on survival. CLINICAL TRIAL: "Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic Multi-Detector Computed Tomography (MDCT) Angiography" registered at http://clinicaltrials.gov/ct2/show/NCT01351714.

Navigating the mesentery: part II. Vascular abnormalities and a review of the literature.

AIM: Vascular abnormalities present advantages and/or disadvantages for the patient undergoing surgery. The aims of this study were to define, classify and demonstrate the courses, and to assess the clinical value, of arterial and venous abnormalities in the central mesentery. METHOD: We conducted a review of the anatomy of 340 patients planned for enrolment in the 'Safe Radical D3 Right Hemicolectomy for Cancer through Preoperative Biphasic MDCT Angiography' trial, 312 of whom were submitted to surgery. Vascular abnormalities were analysed in context with surgical notes and images. A meta-analysis of the literature was performed. RESULTS: Arterial Abnormalities were found in 28 (8.2%) of the 340 patients and were classified into the following three groups based on anticipated surgical difficulty: group 1, accessory or replaced arteries to solid organs [14 (4.1%)]; group 2, arterial shunts [11 (3.2%)] between the coeliac trunk and the superior mesenteric artery, which resulted in bleeding in three patients; and group 3, common stem abnormalities [3 (0.9%)]. Two groups of superior mesenteric vein abnormalities were noted. The first included morphological abnormalities in a single vein [4 (1.2%)]: aneurysm [1 (0.3%)]; and ring variants of principal tributaries [3 (0.9%)]. The second included double superior mesenteric vein trunks [31 (9.1%)]: genuine bifid [10 (2.9%)]; and pseudo bifid [21 (6.2%)]. The meta-analysis revealed 26 articles, including 10 series of anatomical dissections or angiographies [1970 cases with 205 (10.4%) arterial abnormalities] and 16 case reports, none of which described a clinical or surgical setting. CONCLUSION: Vascular abnormalities occur frequently. Arterial abnormalities are a hazard when inadvertent injury occurs during surgery. Preoperative knowledge of a bifid superior mesenteric vein is useful.

Navigating the mesentery: a comparative pre- and per-operative visualization of the vascular anatomy.

AIM: Awareness of anatomy is critical for performing safe surgery within the root of the mesentery. Our aim was to investigate the anatomical relationship between the superior mesenteric artery (SMA) and vein (SMV) and their branches within a predefined D3 area of the right colon and to compare preoperatively established three-dimensional (3D) mesenteric vessel anatomy from CT with that found at surgery. METHOD: Prospective data were collected on 139 patients included in the 'Safe Radical D3 Right Hemicolectomy for Cancer Through Preoperative Biphasic Multi-detector Computed Tomography (MDCT) Angiography' trial. CT data sets were 3D reconstructed before surgery and compared with photographs taken during the operation. RESULTS: The ileocolic artery was present and correctly identified in all patients and crossed the SMV anteriorly in 58 (41.7%). Seventeen patients had a right colic artery at surgery and there were three false-negative and one false-positive CT findings, yielding a diagnostic accuracy of 97.1%, sensitivity of 85.7% and specificity of 95.2%. Positive and negative predictive values were 94.7% and 97.5%, respectively. The middle colic artery was absent in one (0.7%) patient and multiple (nine double and one triple) in 10 (7.2%) patients. A mean of 3.8 ± 1.2 jejunal arteries and 2.0 ± 0.8 jejunal veins arose from the SMA and SMV. Jejunal veins crossed the SMA in the D3 area anteriorly in 30.9% of patients. In 26 (18.7%) patients, additional veins drained into the SMV, including pancreaticoduodenal in 16, right colic in six and both in two. The inferior mesenteric vein entered the SMV in 58 (41.7%) patients and crossed the D3 area in three (2.2%). CONCLUSION: CT-reconstructed anatomy has high specificity, sensitivity, accuracy and reliability.