Usefulness of the preoperative administration of tegafur suppositories as alternative adjuvant chemotherapy for patients with resectable stage II or III colorectal cancer: a KODK4 multicenter randomized control trial

Thiolated pectin-chitosan composites: Potential mucoadhesive drug delivery system with selective cytotoxicity towards colorectal cancer

Mucoadhesive drug delivery systems (DDS) may promote safer chemotherapy for colorectal cancer (CRC) by maximizing local drug distribution and residence time. Carbohydrate polymers, e.g. pectin (P) and chitosan (CS), are potential biomaterials for CRC-targeted DDS due to their gelling ability, mucoadhesive property, colonic digestibility, and anticancer activity. Polymer mucoadhesion is augmentable by thiolation, e.g. pectin to thiolated pectin (TP). Meanwhile, P-CS polyelectrolyte complex has been shown to improve structural stability. Herein, we fabricated, characterized, and evaluated 5-fluorouracil-loaded primary DDS combining TP and CS as a composite (TPCF) through triple crosslinking actions (calcium pectinate, polyelectrolyte complex, disulfide). Combination of these crosslinking yields superior mucoadhesion property relative to single- or dual-crosslinked counterparts, with comparable drug release profile and drug compatibility. PCF and TPCF exhibited targeted cytotoxicity towards HT29 CRC cells with milder cytotoxicity towards HEK293 normal cells. In conclusion, TP-CS composites are promising next-generation mucoadhesive and selectively cytotoxic biomaterials for CRC-targeted DDS.

Diagnostic performance of MRI- versus MDCT-categorized T3cd/T4 for identifying high-risk stage II or stage III colon cancers: a pilot study

PURPOSE

The aim of this study was to determine the diagnostic performance of magnetic resonance imaging (MRI)-categorized T3cd/T4 tumors for identifying high-risk stage II or stage III cancer in patients with curatively resectable colon cancer in comparison to that of multidetector computed tomography (MDCT).

MATERIALS AND METHODS

Thirty-eight patients with histopathologically indicated adenocarcinomas prospectively underwent MRI of the colon. Two radiologists independently and retrospectively assessed for T-category, including T3 substage (≤ T3ab vs. ≥ T3cd). The diagnostic accuracies and interreader agreements between assessments using each modality were compared using a pairwise comparison of receiver-operating characteristic curves and a weighted κ statistic, respectively.

RESULTS

Twenty-nine patients (76.3%) were histopathologically diagnosed with high-risk stage II or stage III colon cancer. The false-positive rate with MRI was lower than that with MDCT (0% vs. 7.9% for reader 1, 2.6% vs. 10.6% for reader 2). The diagnostic performance of MRI was better than that of MDCT across both readers (AUC: 0.707 vs. 0.506 [P = 0.032] for reader 1, 0.651 vs. 0.485 [P = 0.055] for reader 2). Moreover, MRI interreader agreement for the assessment of T3cd/T4 was significantly better than that of MDCT (κ = 0.821 vs. 0.391 [P = 0.017]).

CONCLUSION

The diagnostic performance of MR imaging of the colon may be better than that of MDCT for identifying high-risk stage II or stage III cases. Particularly, colon MRI reduced the false-positive rate and improved the interreader agreement, although further studies with a larger sample size are required.

Neoadjuvant chemotherapy followed by surgery versus surgery alone for colorectal cancer: meta-analysis of randomized controlled trials

Effects of neoadjuvant chemotherapy (NAC) on colorectal cancer (CRC) have been largely studied, while its survival and surgical benefits remain controversial. This study aimed to perform a meta-analysis of randomized controlled trials (RCTs), comparing efficacy and safety of NAC plus surgery with surgery alone (SA) for CRC. We searched systematically databases of MEDLINE, EMBASE, and the Cochrane Library for RCTs comparing NAC and surgery with SA for treating CRC. References of relevant articles and reviews, conference proceedings, and ongoing trial databases were also screened. Primary outcomes included overall and disease-free survivals, total and perioperative mortalities, recurrence, and metastasis. Meta-analysis was performed where possible comparing parameters using relative risks (RRs). Safely analysis was then performed. Outcomes for stages II and III tumors were also meta-analyzed, respectively. Our study was conducted according to intention-to-treat analysis. A total of 6 RCTs comparing NAC (n=1393) with SA (n=1358) published from 2002 to 2012 were identified. Compared with SA, NAC tended to reduce overall recurrences (21.86% vs 25.15%, RR: 0.70, 95% confidence interval [CI]: 0.32-1.56, P=0.09), and prevent vascular invasion (32.30% vs 43.12%, RR: 0.73, 95% CI: 0.53-1.00, P=0.05); and significantly lowered distant metastasis (15.58% vs 23.80%, RR: 0.66, 95% CI: 0.50-0.86, P=0.002), especially liver metastasis rate (13.00% vs 18.25%, RR: 0.71, 95% CI: 0.51-0.99, P=0.04), and associated with higher incidence of ypT0-2 cases upon resection (13.04% vs 6.42%, RR: 2.36, 95% CI: 1.02-5.44, P=0.04). All other parameters were comparable. NAC-related side-effects were generally mild. NAC mainly benefited patients with stage III disease. NAC could prevent recurrence and metastasis, associates with better tumor stages upon resection, and potentially impedes vascular invasion among CRC patients. NAC does not contribute to significant survival benefits for CRC, and compares favorably with SA in tumor-free resection rates, nodal status upon resection, and postsurgical complications. This level 1a evidence does not support NAC to obviously outweigh SA in terms of survival and surgical benefits for CRC currently.

Dosage uniformity problems which occur due to technological errors in extemporaneously prepared suppositories in hospitals and pharmacies

The availability of suppositories in Hungary, especially in clinical pharmacy practice, is usually provided by extemporaneous preparations. Due to the known advantages of rectal drug administration, its benefits are frequently utilized in pediatrics. However, errors during the extemporaneous manufacturing process can lead to non-homogenous drug distribution within the dosage units. To determine the root cause of these errors and provide corrective actions, we studied suppository samples prepared with exactly known errors using both cerimetric titration and HPLC technique. Our results show that the most frequent technological error occurs when the pharmacist fails to use the correct displacement factor in the calculations which could lead to a 4.6% increase/decrease in the assay in individual dosage units. The second most important source of error can occur when the molding excess is calculated solely for the suppository base. This can further dilute the final suppository drug concentration causing the assay to be as low as 80%. As a conclusion we emphasize that the application of predetermined displacement factors in calculations for the formulation of suppositories is highly important, which enables the pharmacist to produce a final product containing exactly the determined dose of an active substance despite the different densities of the components.