Value of orthogonal axial MR images in preoperative T staging of gastric cancer.

PURPOSE: To assess the value of orthogonal axial images (OAI) of MRI in gastric cancer T staging. METHODS: This retrospective study enrolled 133 patients (median age, 63 [range, 24-85] years) with gastric adenocarcinoma who underwent both CT and MRI followed by surgery. MRI lacking or incorporating OAI and CT images were evaluated, respectively. Diagnostic performance (accuracy, sensitivity, and specificity) for each T stage, overall diagnostic accuracy and rates of over- and understaging were quantified employing pathological T stage as a reference standard. The McNemar's test was performed to compare the overall accuracy. RESULTS: Among patients with pT1-pT4 disease, MRI with OAI (accuracy: 88.7-94.7%, sensitivity: 66.7-93.0%, specificity: 91.5-100.0%) exhibited superior diagnostic performance compared to MRI without OAI (accuracy: 81.2-88.7%, sensitivity: 46.2-83.1%, specificity: 85.5-99.1%) and CT (accuracy: 88.0-92.5%, sensitivity: 53.3-90.1%, specificity: 88.7-98.1%). The overall accuracy of MRI with OAI was significantly higher (83.5%) than that of MRI without OAI (67.7%) (p < .001). However, there was no significant difference in the overall accuracy of MRI with OAI and CT (78.9%) (p = .35). The over- and understaging rates of MRI with OAI (12.0, 4.5%) were lower than those of MRI without OAI (21.8, 10.5%) and CT (12.8, 8.3%). CONCLUSION: OAI play a pivotal role in the T staging of gastric cancer. MRI incorporating OAI demonstrated commendable performance for gastric cancer T-staging, with a slight tendency toward its superiority over CT.

MRI for nodal restaging after neoadjuvant therapy in rectal cancer with histopathologic comparison.

BACKGROUND: After neoadjuvant therapy, most of the lymph nodes (LNs) will shrink and disappear in patients with rectal cancer. However, LNs that are still detectable on MRI carry a risk of metastasis. This study aimed to evaluate the performance of the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) criterion (short-axis diameter ≥ 5 mm) in diagnosing malignant LNs in patients with rectal cancer after neoadjuvant therapy, and whether nodal morphological characteristics (including shape, border, signal homogeneity, and enhancement homogeneity) could improve the diagnostic efficiency for LNs ≥ 5 mm. METHODS: This retrospective study included 90 patients with locally advanced rectal cancer who underwent surgery after neoadjuvant therapy and performed preoperative MRI. Two radiologists independently measured the short-axis diameter of LNs and evaluated the morphological characteristics of LNs ≥ 5 mm in consensus. With a per node comparison with histopathology as the reference standard, a ROC curve was performed to evaluate the diagnostic performance of the size criterion. For categorical variables, either a χ2 test or Fisher's exact test was used. RESULTS: A total of 298 LNs were evaluated. The AUC for nodal size in determining nodal status was 0.81. With a size cutoff value of 5 mm, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 65.9%, 87.0%, 46.8%, 93.6% and 83.9%, respectively. No significant differences were observed in any of the morphological characteristics between benign and malignant LNs ≥ 5 mm (all P > 0.05). CONCLUSIONS: The ESGAR criterion demonstrated moderate diagnostic performance in identifying malignant LNs in patients with rectal cancer after neoadjuvant therapy. It was effective in determining the status of LNs < 5 mm but not for LNs ≥ 5 mm, and the diagnostic efficiency could not be improved by considering nodal morphological characteristics.

Extra-wound fixation: a modified tie-over dressing technique for skin graft.

OBJECTIVE: Tie-over dressing is the most frequently used technique of skin grafting. However, many deficiencies affecting the outcome have been reported. We hereby introduce a modified method, termed the 'extra-wound fixation technique', for skin dressing, and evaluate the complications and clinical outcomes. METHOD: In this retrospective cross-sectional study we analysed the medical records of patients treated between January 2012 and December 2017. All patients received full thickness skin grafts. Patients were divided equally into to groups: patients were treated using the extra-wound fixation technique, and the remaining, randomly selected patients treated using the traditional tie-over method. The extra-wound fixation technique uses the traditional tie-over dressing method followed by additional stitches made in healthy skin locating 0.5-1.0 cm laterally to the wound edge. The follow-up outcomes between the two groups were compared using the Chi-square test. RESULTS: A total of 38 patients took part (19 patients in each group). The follow-up duration was 1-6 months. No raised edges were observed in any of the patients. Prolonged follow-up demonstrated that the grafted skin texture became soft with a thin layer of adipose tissue, and elasticity was gradually improved along with the regeneration of dermoelastic fibre. The colour was similar to the normal skin with a smooth surface. Compared with the traditional method, the extra-wound fixation technique significantly improved the survival of the grafted skin (p=0.008), reduced the risk of laceration of the skin (p=0.001), and eliminated crater rim-like appearances (p=0.020). CONCLUSION: The extra-wound fixation technique could be used for different skin grafts and improve clinical outcomes compared with the traditional tie-over dressing method.

Hederagenin potentiated cisplatin- and paclitaxel-mediated cytotoxicity by impairing autophagy in lung cancer cells.

Autophagy inhibition has been demonstrated to increase the efficacy of conventional chemotherapy. In this study, we identified hederagenin, a triterpenoid derived from Hedera helix, as a potent inhibitor of autophagy and then hypothesized that hederagenin might synergize with chemotherapeutic drugs (e.g., cisplatin and paclitaxel) to kill lung cancer cells. Firstly, we observed that hederagenin induced the increased autophagosomes in lung cancer cells concomitantly with the upregulation of LC3-II and p62, which indicated the impairment of autophagic flux. The colocalization assay indicated hederagenin could not block the fusion of lysosomes and autophagosomes, whereas the lysosomal acidification might be inhibited by hederagenin as revealed by the reduced staining of acidity-sensitive reagents (i.e., Lysotracker and acridine orange). The aberrant acidic environment then impaired the function of lysosome, which was evidenced by the decrease of mature cathepsin B and cathepsin D. Lastly, hederagenin, in agree with our hypothesis, promoted pro-apoptotic effect of cisplatin and paclitaxel with the accumulation of reactive oxygen species (ROS); while the synergistic effect could be abolished by the ROS scavenger, N-acetyl-L-cysteine. These data summarily demonstrated hederagenin-induced accumulation of ROS by blocking autophagic flux potentiated the cytotoxicity of cisplatin and paclitaxel in lung cancer cells.

Warning criteria for intraoperative neurophysiologic monitoring.

PURPOSE OF REVIEW: Intraoperative changes in somatosensory (SEP) and motor evoked potentials (MEPs) may indicate potential injury to the spinal cord and will require timely intervention to prevent permanent damage. This review focuses on the validity of currently recommended warning criteria for intraoperative evoked potential monitoring. RECENT FINDINGS: Current guideline recommends a decrease in SEP amplitude by 50% and MEP amplitude by 50-100% as warning signals for injury to the ascending sensory and descending motor pathway, respectively. On the basis of cohort studies, the diagnostic accuracy of SEP and MEP to predict postoperative neurologic deficits was variable. Importantly, 0.1-4.1% of monitored patients suffered postoperative neurologic deficit despite apparently normal SEP and MEP recordings (i.e. false negative events). These data suggested that the true warning criteria may be lower than previously acknowledged. A systematic review of studies that reported changes in SEP or MEP monitoring and postoperative neurological outcome showed an association between changes in monitoring signals and postoperative neurological deficits. However, the confidence intervals were wide and it is not possible to determine a threshold value in SEP or MEP amplitude beyond which may indicate neurologic deficit. SUMMARY: Current recommendations for warning criteria during intraoperative evoked potential monitoring are empirically derived. Until a threshold that predicts spinal cord injury can be accurately determined, it remains difficult to define the clinical utility of intraoperative neurophysiologic monitoring.