Showing papers by "Geerard L. Beets published in 2012"

Diffusion-weighted MRI in rectal cancer: apparent diffusion coefficient as a potential noninvasive marker of tumor aggressiveness.

Abstract: Purpose: To assess the value of diffusion-weighted MR imaging (DWI) as a potential noninvasive marker of tumor aggressiveness in rectal cancer, by analyzing the relationship between tumoral apparent diffusion coefficient (ADC) values and MRI and histological prognostic parameters. Materials and Methods: Fifty rectal cancer patients underwent primary staging MRI including DWI before surgery and neo-adjuvant therapy. In 47, surgery was preceded by short-course radiation therapy (n = 28) or long-course chemoradiation therapy (n = 19). Mean tumor ADC was measured and compared between subgroups based on pretreatment CEA levels, MRI parameters (mesorectal fascia - MRF - status; T-stage; N-stage) and histological parameters (differentiation grade: poorly differentiated, poorly moderately differentiated, moderately differentiated, moderately well differentiated, well-differentiated; lymphangiovascular invasion). Results: Mean tumor ADCs differ between MRF-free versus MRF-invaded tumors (P = 0.013), the groups of cN0 versus cN+ cancers (P = 0.011), and between the several groups of histological differentiation grades (P = 0.025). There was no significant difference in mean ADCs between the various groups of CEA levels, the T stage, and the presence of lymphangiovascular invasion. Conclusion: Lower ADC values were associated with a more aggressive tumor profile. Significant correlations were found between mean ADC values and radiological MRF status, N stage and differentiation grade. ADC has the potential to become an imaging biomarker of tumor aggressiveness profile. J. Magn. Reson. Imaging 2012;35:1365–1371. © 2012 Wiley Periodicals, Inc.

T-staging of rectal cancer: accuracy of 3.0 Tesla MRI compared with 1.5 Tesla.

Abstract: Objectives Magnetic resonance imaging (MRI) is not accurate in discriminating T1-2 from borderline T3 rectal tumors. Higher resolution on 3 Tesla-(3T)-MRI could improve diagnostic performance for T-staging. The aim of this study was to determine whether 3T-MRI compared with 1.5 Tesla-(1.5T)-MRI improves the accuracy for the discrimination between T1-2 and borderline T3 rectal tumors and to evaluate reproducibility.

Randomized clinical trial on chronic pain after the transinguinal preperitoneal technique compared with Lichtenstein's method for inguinal hernia repair (Br J Surg 2012; 99: 1365-1373)

Abstract: Background: Preliminary experience has suggested that preperitoneal mesh positioning causes less chronic pain than Lichtenstein’s technique for inguinal hernia repair. Therefore, a randomized clinical trial was conducted with the aim of evaluating the incidence of postoperative chronic pain after transinguinal preperitoneal (TIPP) mesh repair versus Lichtenstein’s technique. Methods: Patients with a primary unilateral inguinal hernia were randomized to either TIPP or Lichtenstein’s repair in two training hospitals. The primary outcome was the number of patients with chronic pain after surgery. Secondary outcomes were adverse events. Follow-up was scheduled after 14 days, 3 months and 1 year. Patients and outcome assessors were blinded. Results: A total of 302 patients were randomized to TIPP (143) or Lichtenstein (159) repair. Baseline characteristics were comparable in the two groups. Some 98·0 per cent of the patients were included in the analysis (141 in the TIPP group and 155 in the Lichtenstein group). Significantly fewer patients in the TIPP group had continuous chronic pain 1 year after surgery: five patients (3·5 per cent) versus 20 patients (12·9 per cent) in the Lichtenstein group (P = 0·004). An additional 12 patients (8·5 per cent) in the TIPP group and 60 (38·7 per cent) in the Lichtenstein group experienced pain during activity (P = 0·001). There were two patients with recurrence in the TIPP group and four in the Lichtenstein group, but no significant differences were found in other severe adverse events between the groups. Conclusion: Fewer patients had continuous chronic pain at 1 year after the TIPP mesh inguinal hernia repair compared with Lichtenstein’s repair. Registration number: ISRCTN93798494 (http://www.controlled-trials.com).

Critical appraisal of the 'wait and see' approach in rectal cancer for clinical complete responders after chemoradiation (Br J Surg 2012; 99: 897-909).

Abstract: Background: Some 10–20 per cent of patients with locally advanced rectal cancer achieve a pathological complete response (pCR) at surgery following preoperative chemoradiation (CRT). Some demonstrate a sustained clinical complete response (cCR), defined as absence of clinically detectable residual tumour after CRT, and do not undergo resection. The aim of this review was to evaluate non-operative treatment of rectal cancer after CRT, and the outcome of patients observed without radical surgery. Methods: A systematic computerized search identified 30 publications (9 series, 650 patients) evaluating a non-operative approach after CRT. Original data were extracted and tabulated, and study quality evaluated. The primary outcome measure was cCR. Secondary outcome measures included locoregional failure rate, disease-free survival and overall survival. Results: The most recent Habr-Gama series reported a low locoregional failure rate of 4·6 per cent, with 5-year overall and disease-free survival rates of 96 and 72 per cent respectively. These findings were supported by a small prospective Dutch study. However, other retrospective series have described higher recurrence rates. All studies were heterogeneous in staging, inclusion criteria, study design and rigour of follow-up after CRT, which might explain the different outcomes. The definition of cCR was inconsistent, with only partial concordance with pCR. The results suggested that patients who are observed, but subsequently fail to sustain a cCR, may fare worse than those who undergo immediate tumour resection. Conclusion: The rationale of a ‘wait and see’ policy relies mainly on retrospective observations from a single series. Proof of principle in small low rectal cancers, where clinical assessment is easy, should not be extrapolated uncritically to more advanced cancers where nodal involvement is common. Long-term prospective observational studies with more uniform inclusion criteria are required to evaluate the risk versus benefit.

Is a Diverting Stoma Always Necessary for a Low Anterior Resection of a Rectal Cancer

Abstract: A diverting stoma decreases both the incidence and the consequences of anastomotic failure after a low anterior resection for rectal cancer. The available evidence supports a routine diverting stoma for all patients rather than a selective approach. There is no solid evidence favouring either ileostomy or colostomy.