Magnetic resonance imaging as a predictor of surgical outcome in patients with local pelvic recurrence of colorectal cancer

Imaging features and correlation with short-term prognosis in laparoscopic radical resection of colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a malignant tumor with high morbidity and mortality rates worldwide. With the development of medical imaging technology, imaging features are playing an increasingly important role in the prognostic evaluation of CRC. Laparoscopic radical resection is a common surgical approach for treating CRC. However, research on the link between preoperative imaging and short-term prognosis in this context is limited. We hypothesized that specific preoperative imaging features can predict the short-term prognosis in patients undergoing laparoscopic CRC resection.

AIM

To investigate the imaging features of CRC and analyze their correlation with the short-term prognosis of laparoscopic radical resection.

METHODS

This retrospective study conducted at the Affiliated Cancer Hospital of Shandong First Medical University included 122 patients diagnosed with CRC who underwent laparoscopic radical resection between January 2021 and February 2024. All patients underwent magnetic resonance imaging (MRI) and were diagnosed with CRC through pathological examination. MRI data and prognostic indicators were collected 30 days post-surgery. Logistic regression analysis identified imaging features linked to short-term prognosis, and a receiver operating characteristic (ROC) curve was used to evaluate the predictive value.

RESULTS

Among 122 patients, 22 had irregular, low-intensity tumors with adjacent high signals. In 55, tumors were surrounded by alternating signals in the muscle layer. In 32, tumors extended through the muscular layer and blurred boundaries with perienteric adipose tissue. Tumor signals appeared in the adjacent tissues in 13 patients with blurred gaps. Logistic regression revealed differences in longitudinal tumor length, axial tumor length, volume transfer constant, plasma volume fraction, and apparent diffusion coefficient among patients with varying prognostic results. ROC analysis indicated that the areas under the curve for these parameters were 0.648, 0.927, 0.821, 0.809, and 0.831, respectively. Sensitivity values were 0.643, 0.893, 0.607, 0.714, and 0.714, and specificity 0.702, 0.904, 0.883, 0.968, and 0.894 (P < 0.05).

CONCLUSION

The imaging features of CRC correlate with the short-term prognosis following laparoscopic radical resection. These findings provide valuable insights for clinical decision-making.

Magnetic Fields and Cancer: Epidemiology, Cellular Biology, and Theranostics

Humans are exposed to a complex mix of man-made electric and magnetic fields (MFs) at many different frequencies, at home and at work. Epidemiological studies indicate that there is a positive relationship between residential/domestic and occupational exposure to extremely low frequency electromagnetic fields and some types of cancer, although some other studies indicate no relationship. In this review, after an introduction on the MF definition and a description of natural/anthropogenic sources, the epidemiology of residential/domestic and occupational exposure to MFs and cancer is reviewed, with reference to leukemia, brain, and breast cancer. The in vivo and in vitro effects of MFs on cancer are reviewed considering both human and animal cells, with particular reference to the involvement of reactive oxygen species (ROS). MF application on cancer diagnostic and therapy (theranostic) are also reviewed by describing the use of different magnetic resonance imaging (MRI) applications for the detection of several cancers. Finally, the use of magnetic nanoparticles is described in terms of treatment of cancer by nanomedical applications for the precise delivery of anticancer drugs, nanosurgery by magnetomechanic methods, and selective killing of cancer cells by magnetic hyperthermia. The supplementary tables provide quantitative data and methodologies in epidemiological and cell biology studies. Although scientists do not generally agree that there is a cause-effect relationship between exposure to MF and cancer, MFs might not be the direct cause of cancer but may contribute to produce ROS and generate oxidative stress, which could trigger or enhance the expression of oncogenes.

Predictive Nomogram for the Prediction of Early Recurrence of Colorectal Cancer

Aim

The prognosis of colorectal cancer (CRC) individuals after curative resection is not satisfactory due to the early recurrence. We sought to identify the affecting features of early recurrence in CRC patients.

Methods

A total of 3500 CRC patients underwent curative resection were retrospectively incorporated into our study. Among them, 246 patients exhibited tumor recurrence: 121 had early recurrence (≤1 year after operation) and 125 had late recurrence (>1 year after operation). A total of 246 CRC patients with recurrence were randomly assigned into the training group (N=177) or validation group (N=69) based on the ratio of 7:3. LASSO COX regression and support vector machine (SVM) were utilized to screen for the significant clinical indexes associated with the presence of early recurrence. Recurrent nomogram was created based on the above informative parameters to predict the probability of early recurrence.

Results

Proportion of advanced TNM stage, platelet count, systemic immune-inflammation index (SII), mean corpuscular hemoglobin concentration (MCHC), CA-199, CA-125, lactate dehydrogenase, total bile acid (TBA), urea nitrogen were significantly higher in early recurrence group compared with that in late recurrence group. Results from LASSO COX regression and support vector machine (SVM) revealed that TNM stage, CA-199, CA125, SII and TBA were strong predictors for the presence of early recurrence among postoperative CRC patients in the training group. The recurrent nomogram based on the five predictors exhibited good predictive performance as calculated by C-index (0.846, 95% CI 0.789-0.902 in the training group and 0.799, 95% CI 0.697-0.902 in the validation group) for the prediction of early recurrence. Moreover, the recurrent nomogram exhibited not only encouraging calibration ability, but also great clinical utility both in the training group and validation group.

Conclusion

TNM stage, CA-199, CA125, SII and TBA were closely correlated with the presence of early recurrence of CRC patients. The recurrent nomogram held well predictive ability for the identification of CRC patients with early recurrence.