Effectiveness and safety of monoclonal antibodies for metastatic colorectal cancer treatment: systematic review and meta-analysis.

BACKGROUND: The effectiveness of chemotherapy (CT) for select cases of metastatic colorectal cancer (MCRC) has been well established in the literature, however, it provides limited benefits and in many cases constitutes a treatment with high toxicity. The use of specific molecular biological treatments with monoclonal antibodies (MA) has been shown to be relevant, particularly for its potential for increasing the response rate of the host to the tumour, as these have molecular targets present in the cancerous cells and their microenvironment thereby blocking their development. The combination of MA and CT can bring a significant increase in the rate of resectability of metastases, the progression-free survival (PFS), and the global survival (GS) in MCRC patients. OBJECTIVE: To assess the effectiveness and safety of MA in the treatment of MCRC. METHODS: A systematic review was carried out with a meta-analysis of randomised clinical trials comparing the use of cetuximab, bevacizumab, and panitumumab in the treatment of MCRC. RESULTS: Sixteen randomised clinical trials were selected. The quality of the evidence on the question was considered moderate and data from eight randomised clinical trials were included in this meta-analysis. The GS and PFS were greater in the groups which received the MA associated with CT, however, the differences were not statistically significant between the groups (mean of 17.7 months versus 17.1 months; mean difference of 1.09 (CI: 0.10-2.07); p = 0.84; and 7.4 versus 6.9 months. mean difference of 0.76 (CI: 0.08-1.44); p = 0.14 respectively). The meta-analysis was not done for any of the secondary outcomes. CONCLUSION: The addition of MA to CT for patients with metastatic colorectal cancer does not prolong GS and PFS.

Segmentation of liver, its vessels and lesions from CT images for surgical planning.

BACKGROUND: Cancer treatments are complex and involve different actions, which include many times a surgical procedure. Medical imaging provides important information for surgical planning, and it usually demands a proper segmentation, i.e., the identification of meaningful objects, such as organs and lesions. This study proposes a methodology to segment the liver, its vessels and nodules from computer tomography images for surgical planning. METHODS: The proposed methodology consists of four steps executed sequentially: segmentation of liver, segmentation of vessels and nodules, identification of hepatic and portal veins, and segmentation of Couinaud anatomical segments. Firstly, the liver is segmented by a method based on a deformable model implemented through level sets, of which parameters are adjusted by using a supervised optimization procedure. Secondly, a mixture model is used to segment nodules and vessels through a region growing process. Then, the identification of hepatic and portal veins is performed using liver anatomical knowledge and a vein tracking algorithm. Finally, the Couinaud anatomical segments are identified according to the anatomical liver model proposed by Couinaud. RESULTS: Experiments were conducted using data and metrics brought from the liver segmentation competition held in the Sliver07 conference. A subset of five exams was used for estimation of segmentation parameter values, while 15 exams were used for evaluation. The method attained a good performance in 17 of the 20 exams, being ranked as the 6th best semi-automatic method when comparing to the methods described on the Sliver07 website (2008). It attained visual consistent results for nodules and veins segmentation, and we compiled the results, showing the best, worst, and mean results for all dataset. CONCLUSIONS: The method for liver segmentation performed well, according to the results of the numerical evaluation implemented, and the segmentation of liver internal structures were consistent with the anatomy of the liver, as confirmed by a specialist. The analysis provided evidences that the method to segment the liver may be applied to segment other organs, especially to those whose distribution of voxel intensities is nearly Gaussian shaped.

Selective internal radiation therapy with 90Y microspheres for colorectal liver metastases: single-centre experience with 100 patients.

BACKGROUND: Many patients with colorectal liver metastases die from liver-only disease. Selective internal radiation therapy (SIRT) is an evolving method suitable for treating patients with non-resectable metastatic liver disease. METHODS: One hundred patients with advanced colorectal liver metastases were treated with SIRT. A single dose of between 2.0 and 3.0 GBq of (90)Y microspheres was given into the hepatic artery either by a surgically implanted portacath or a percutaneous femoral catheter. When a port was used (n = 87), SIRT was followed by hepatic arterial chemotherapy with 5-fluorouracil. RESULTS: Treatment-related morbidity occurred in 11 patients. Responses to SIRT were assessed by serial computed tomography scans and carcinoembryonic antigen (CEA) measurement. Median CEA level 3 months after SIRT (expressed as percentage of initial CEA) was 18%. Only 5 of 80 patients (6.25%) scanned at 3 months showed disease progression. Survival was significantly more in those who experienced a good tumour marker response and in those who were slow to develop extrahepatic disease. Survival was independently influenced by the use of ongoing hepatic arterial chemotherapy, the extent of liver involvement and the lymph node status of the original primary tumour. CONCLUSION: Selective internal radiation therapy is a very effective and well-tolerated regional treatment for colorectal liver metastases, which should be considered for those with liver-only metastatic disease.

Lymph Nodes Number in Surgical Specimen Modifies Prognosisin Advanced Stage Gastric Cancer Patients– Study of the Will-Rogers Phenomenon

Background: The AJCC 2002 staging system recommends the study of at least 15 lymph nodes in the surgical specimen. Thisnumber varies and sometimes it is not achieved since it is influenced by surgeons, pathologists and patients and may modifythe patient’s staging and survival. Methods: This is an observational study of 201 patients with gastric cancer submitted tosurgery in the period of January 1997 to December 2001, and followed-up until July 2003 in the Brazilian National CancerInstitute. Data related to surgeon and pathologist productivity as well as survival were analyzed. Results: All patients that haveundergone D2 lymphadenectomy had more than 15 lymph nodes. The factors related to varied number of lymph nodes were:surgeon (31.5±9.3 to 43.8 ±16.8); surgical procedure (total gastrectomy, 41.4 ±15.5); extended resection (40.8 ±15.9);pN3 and stage IV (55.1 ±15.8). Multivariate analysis showed the surgeon as an independent variable (p=0,02). The morelymph nodes studied, the more nodal metastasis found (p=0.01), but this fact has been significant only in pT3 patients(p=0.007). The variables related to survival have been surgical procedure, resection of another organ, site of the tumor; pT andpN. The independent variables have been pT (p=0,01) and pN (p=0,004). Conclusion: The surgeon’s technique is the mainfactor related to number of lymph nodes in the surgical specimen and for accurate staging of pT3 patients over 30 lymph nodesarenecessary.