Contribution of endorectal ultrasound, magnetic resonance imaging and positron emission tomography to operation strategy in rectal cancer

Introduction: Colorectal cancers are the most commonly seen cancers of gastrointestinal tract. Preoperative staging is very important especially in rectal cancer patients. That is because of multipl different management modalities exist according to staging. Staging prefers to apply appropriate treatment modality for patient. Purpose: The effect of ERUS, MRI and PET-CT evaluations of rectal cancer patients on operative strategy was investigated. Materials and methods: In this study, between october 2010 – april 2012, 30 patients who are diagnosed as rectal cancer clinically and histopathologically are evaluated with ERUS, MR and PET-CT preoperatively and results were compared with histopathologic findings. Results: Between october 2010 – april 2012, 30 patients who are diagnosed as rectal cancer with biopsy are included to this study. (20 male (66,6%), 10 female (33,3%) and their ages are 38-75 years old, 21 of them received neoadjuvant treatment and 9 of them did not received.) All patients are evaluated with MRI, ERUS and PET-CT preoperatively. Rectal cancer patients who are primarily operated from rectal adenocarcinoma are included in this study. For T staging, preoperative MRI, ERUS and PET-CT staged 9 (%31) , 12 (%41) , 12 (%40) of 30 patients accurately. For N staging, preoperative MRI, ERUS and PET-CT staged 15 (%51), 16 (%55,1) , 17 (%56,6) of 30 patients accurately. In comparison to other modalities, PET-CT did not yield a significant difference in staging and did not change operation strategy. PET-CT detected distant metastasis in 3 patients.One of them was liver and two of them were lung metastasis. Biopsies from mass predicted as lung metastasis did not result as metastasis. PET-CT has high rates of false positivity to detect distant metastasis. In statistical analysis, significant p values for evaluation could not be obtained. Conclusion: Efficacy of routine use of PET-CT on staging, evaluation of T, N and extramesorectal spread could not be shown