Colorectal carcinoma evaluation with CT: preoperative staging and detection of postoperative recurrence.

Abstract

CT was performed prior to surgery in 103 patients with colorectal carcinoma to assess its value in staging the tumor. Preoperative IBD scans had sensitivities and specificities of 72.7% and 98.9% in detection of liver metastases, 25.9% and 96% in detection of lymph node metastases, and 61.2% and 80.6% in detection of local extension. Compared with the Duke's classification, CT correctly staged only 47.5% of patients: 16.6% were upstaged, and 83.3% were downstaged. Recurrent tumors developed in 11 of 67 patients followed for more than 24 months. CT depicted recurrence in six patients scanned prior to 12 months. Routine scans obtained at 12 months depicted unsuspected tumor recurrence in three of four patients with proved recurrent disease (one patient with pulmonary metastases did not undergo CT). This study indicates that because of the poor accuracy of CT in preoperative local staging of colorectal carcinoma, it has virtually no useful clinical role in this regard. However, preoperative CT evaluation of the liver can be useful. Routine postoperative CT, combined with fine-needle aspiration biopsy, is useful for detection of recurrent tumor.

Preoperative computed tomography staging of nonmetastatic colon cancer predicts outcome: implications for clinical trials

“…The overall accuracy of T-stage prediction by each of our observers was 60.3 and 60.8% compared with histology, whereas identification of T3/T4 tumours was 85.9 -92.4% sensitive, with a PPV of at least 90 -92%. These results appear to compare favourably with other studies, which have reported sensitivities of between 55 and 61% and specificities of 67 -81% in the detection of 'serosal', 'extramural' or 'local (T3 -T4) invasion (Freeny et al, 1986;Acunas et al, 1990;Zerhouni et al, 1996). However, this relative lack of definition of depth of invasion makes direct comparison between those studies and our own results difficult.…”

“…The reported sensitivities for lymph node detection range between 19 and 97% (Freeny et al, 1986;Acunas et al, 1990;Zerhouni et al, 1996;McAndrew and Saba, 1999;Laghi et al, 2002). Inter-observer agreement ¼ 79% (k ¼ 0.59).…”

“…Most published series have emphasised the value of preoperative CT staging to diagnose metastatic disease (Freeny et al, 1986;Balthazar et al, 1988;Acunas et al, 1990;Kerner et al, 1993;Thoeni, 1997). Many have concluded that preoperative CT staging is of little value other than to exclude distant metastases because of its limited accuracy, particularly in staging early tumours (Thoeni, 1997).…”

“…Previous studies examining the usefulness of preoperative CT for staging of colon cancer have judged its 'accuracy' by comparisons with histology (Freeny et al, 1986;Balthazar et al, 1988;Acunas et al, 1990;Hundt et al, 1999). Although tumour staging has its origins in the histological description of colorectal cancers (Dukes, 1932), its rationale is in the stratification of patients into prognostic categories.…”

Water enema computed tomography (WE-CT) in the local staging of low colorectal neoplasms: comparison with transrectal ultrasound

“…Despite several articles reporting TRUS as the most accurate imaging method for the local staging of rectal tumors [2][3][4], a recent article [5] reported a trend toward overstaging the degree of tumor penetration within the bowel wall. The reported accuracy of CT has been variable, depending on patient selection (early or advanced neoplasia) and, most importantly, on the technical conditions of the examination (presence or absence of rectal distention) [6][7][8][9][10][11]. The purpose of our study was twofold: to compare the results of CT performed with a simultaneous water enema technique (WE-CT) with those of TRUS for the local staging of low colorectal tumors and to define which criteria is more useful in CT detection of metastatic local lymph node involvement.…”