Patients who undergo preoperative chemoradiotherapy for locally advanced rectal cancer restaged by using diagnostic MR imaging: a systematic review and meta-analysis.

PURPOSE: To obtain performance values of magnetic resonance (MR) imaging for restaging locally advanced rectal cancer after neoadjuvant treatment regarding tumor staging, nodal staging, and tumor-free circumferential resection margins (CRMs). MATERIALS AND METHODS: MEDLINE, EMBASE, and Cochrane databases were searched for studies regarding restaging compared with a reference standard by using the terms rectal neoplasms, MR imaging, and chemotherapy. The Quality Assessment of Diagnostic Accuracy Studies tool was used, and data on imaging criteria, histopathologic criteria, and restaging were extracted. Responders were defined as positives and nonresponders, as negatives. Mean sensitivity, mean specificity, and positive and negative likelihood ratios (LRs) were determined by using a bivariate random-effects model. A positive LR greater than 5 implied moderate results for responders. RESULTS: Thirty-three studies evaluated 1556 patients. For tumor stage, mean sensitivity was 50.4%, mean specificity was 91.2%, positive LR was 5.76, and negative LR was 0.54. Diffusion-weighted (DW) imaging showed comparable positive LR with significantly improved sensitivity (P = .01) and negative LR (P = .04). Experienced observers showed higher sensitivity (P = .01) and lower negative LR (P = .03) compared with less experienced observers. For CRM, mean sensitivity, mean specificity, positive LR, and negative LR were 76.3%, 85.9%, 5.40, and 0.28, respectively. For nodal stage per patient, mean sensitivity, mean specificity, positive LR, and negative LR were 76.5%, 59.8%, 1.90, and 0.39, respectively; and for nodal stage on a lesion basis, these values were 90.7%, 73.0%, 3.37, and 0.13, respectively. CONCLUSION: MR imaging showed heterogeneous results of diagnostic performances for restaging rectal cancer after neoadjuvant treatment, but significantly better results were demonstrated when DW imaging was used or with experienced observers. MR imaging can also be used for evaluation of CRM staging, but nodal staging remains challenging.

The relationship of walking distances estimated by the patient, on the corridor and on a treadmill, and the Walking Impairment Questionnaire in intermittent claudication.

OBJECTIVE: Physicians and patients consider the limited walking distance and perceived disability when they make decisions regarding (invasive) treatment of intermittent claudication (IC). We investigated the relationship between walking distances estimated by the patient, on the corridor and on a treadmill, and the Walking Impairment Questionnaire (WIQ) in patients with IC due to peripheral arterial disease. METHODS: This was a single-center, prospective observational cohort study at a vascular laboratory in a university hospital in the Netherlands. The study consisted of 60 patients (41 male) with a median age of 64 years (range, 44-86 years) with IC and a walking distance ≤ 250 m on a standardized treadmill test. Main outcome measures were differences and Spearman rank correlations between pain-free walking distance, maximum walking distance (MWD) estimated by the patient, on the corridor and on a standardized treadmill test, and their correlation with the WIQ. RESULTS: The median patients' estimated, corridor, and treadmill MWD were 200, 200, and 123, respectively (P < .05). Although the median patients' estimated and corridor MWD were not significantly different, there was a difference on an individual basis. The correlation between the patients' estimated and corridor MWD was moderate (r = 0.61; 95% confidence interval [CI], 0.42-0.75). The correlation between patients' estimated and treadmill MWD was weak (r = 0.39; 95%, CI 0.15-0.58). Respective correlations for the pain-free walking distance were comparable. The patients' estimated MWD was moderately correlated with WIQ total score (r = 0.63; 95%, CI 0.45-0.76) and strongly correlated with WIQ distance score (r = 0.81; 95% CI, 0.69-0.88). The correlation between the corridor MWD and WIQ distance score was moderate (r = 0.59; 95% CI, 0.40-0.74). CONCLUSIONS: Patients' estimated walking distances and on a treadmill do not reflect walking distances in daily life. Instruments that take into account the perceived walking impairment, such as the WIQ, may help to better guide and evaluate treatment decisions.