CT and MRI in Preoperative Colon Cancer Staging
Condition: Colonic Neoplasms
MeSH terms: Colonic Neoplasms
Study type: Interventional

Summary: 
      The objective of this study is the evaluation of different imaging methods for the optimal
      preoperative staging of colon cancer patients. Imaging findings will be compared with the
      histopathologic results of the specimen following surgical resection.
    

Detailed description: 
      Over the last years a significant improvement in the treatment of patients with colon cancer
      has been reported. This has been attributed to the improvement of the staging techniques, as
      well as the optimization of the surgical management. However, the current five-year survival
      rates of colon cancer patients in European countries ranges from 32% to 64%. This variation
      could be due to treatment discrepancies and the lack of adherence to the international
      guidelines.

      Surgical treatment of colon cancer includes the radical resection of the tumour (colectomy).
      Following resection, the specimen is histopathologically examined, the disease is staged and
      further treatment is determined. Neoadjuvant treatment (radiotherapy or/and chemotherapy) for
      colon cancer has not been yet approved, unlike rectal cancer, where neoadjuvant treatment is
      recommended for specific disease stages.

      Preoperative staging of colon cancer aims to identify those patients with remote metastatic
      disease, who will, more likely, not benefit from upward surgery. Recent developments in colon
      cancer management, demanding more precise local disease staging, to identify those patients
      who will likely benefit from neoadjuvant chemotherapy, are still at a clinical trial stage.

      Preoperative treatment depends on the disease stage, which is defined by the tumour's
      invasion in the colonic wall, the dissemination in nearby organs or lymph nodes, and the
      presence of distal metastases. The stage is first evaluated radiologically and then confirmed
      via histopathological examination of the specimen. Imaging is an already approved tool for
      the staging of colonic cancer, while in some studies the combination of different imaging
      methods has been reported to improve the initial evaluation.

      Over the last years, evaluation of the circumferential resection margin (CRM) is also
      recommended in the preoperative staging of patients with colon cancer. This assessment is
      particularly important for tumours located at the cecum, right, or left colon, since these
      areas lack of mobile mesocolon and therefore it is possible to infiltrate the retroperitoneal
      resection margin.

      Nevertheless, the retroperitoneal invasion of these tumours has not been evaluated adequately
      as a preoperative marker for both local recurrence and for the selection of patients who may
      benefit from neoadjuvant treatment. In various studies the percentage of retroperitoneal
      resection margin's infiltration was between 7-10% for cecum and right colon adenocarcinomas,
      while its presence was identified as a risk factor for local recurrence. The retroperitoneal
      surface infiltration was preoperatively evaluated with the combination of imaging methods and
      the findings were postoperatively compared with the histopathological features of the
      specimen.

      A more precise, imaging based, preoperative staging, could lead to a more targeted
      neoadjuvant treatment for patients with advanced disease, with the introduction of chemo-
      and/or radiotherapy. This approach could result to the downstaging of the tumour, with better
      short and long term oncological results.
    

Intervention name(s): MRI in colon cancer; CT in colon cancer
Intervention type(s): Diagnostic Test; Diagnostic Test
Intervention description(s): The MRI protocol will include the following imaging series: T1 and T2 in axial and coronal plane before the administration of intravenous contrast, diffuse weight imaging in axial plane and T1 after the administration of intravenous contrast; The CT scan protocol will include the following: per os and intravenous administration of contrast, axial slices of 0.3mm thickness and reconstruction per 1mm, multi-planar reformation and three-dimensional volume rendering
Intervention model: Single Group Assignment
Intervention model description: The study will employ a prospective design
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: colon; cancer; computed tomography; magnetic resonance; diffusion; preoperative; staging