CT imaging-based radiomics signatures improve prognosis prediction in postoperative colorectal cancer.

OBJECTIVE: To investigate the use of non-contrast-enhanced (NCE) and contrast-enhanced (CE) CT radiomics signatures (Rad-scores) as prognostic factors to help improve the prediction of the overall survival (OS) of postoperative colorectal cancer (CRC) patients. METHODS: A retrospective analysis was performed on 65 CRC patients who underwent surgical resection in our hospital as the training set, and 19 patient images retrieved from The Cancer Imaging Archive (TCIA) as the external validation set. In training, radiomics features were extracted from the preoperative NCE/CE-CT, then selected through 5-fold cross validation LASSO Cox method and used to construct Rad-scores. Models derived from Rad-scores and clinical factors were constructed and compared. Kaplan-Meier analyses were also used to compare the survival probability between the high- and low-risk Rad-score groups. Finally, a nomogram was developed to predict the OS. RESULTS: In training, a clinical model achieved a C-index of 0.796 (95% CI: 0.722-0.870), while clinical and two Rad-scores combined model performed the best, achieving a C-index of 0.821 (95% CI: 0.743-0.899). Furthermore, the models with the CE-CT Rad-score yielded slightly better performance than that of NCE-CT in training. For the combined model with CE-CT Rad-scores, a C-index of 0.818 (95% CI: 0.742-0.894) and 0.774 (95% CI: 0.556-0.992) were achieved in both the training and validation sets. Kaplan-Meier analysis demonstrated a significant difference in survival probability between the high- and low-risk groups. Finally, the areas under the receiver operating characteristics (ROC) curves for the model were 0.904, 0.777, and 0.843 for 1, 3, and 5-year survival, respectively. CONCLUSION: NCE-CT or CE-CT radiomics and clinical combined models can predict the OS for CRC patients, and both Rad-scores are recommended to be included when available.

Retrospective study of total neoadjuvant therapy for locally advanced rectal cancer.

Aim: To compare treatment outcomes of total neoadjuvant therapy (TNT) and the standard treatment for locally advanced rectal cancer (LARC). Materials & methods: Patients with LARC (cT2-4 and/or cN1-2) who were treated with preoperative chemoradiotherapy plus induction and consolidation chemotherapy followed by surgery or the standard treatment were recruited. Pathologic complete response (pCR) rate, overall survival, disease-free survival and the sphincter preservation rate as well as safety were evaluated. Results: 49 cases were treated with TNT and 71 cases received the standard treatment. Multivariate analysis demonstrated that TNT and tumor size were independent risk factors for pCR. Grade 3 chemoradiotherapy toxicity and postoperative complications were similar between the two groups. Conclusion: TNT improved the pCR rate for patients with LARC, with tolerable toxicities.

Plain language summary Outcomes of two treatment schemes were compared for locally advanced rectal cancer (LARC), including the new preoperative treatment strategy and conventional standard preoperative chemoradiotherapy. The new preoperative treatment strategy includes the addition of four cycles of preoperative chemotherapy to the standard treatment. A total of 49 cases were treated with the new preoperative treatment strategy and 71 cases received the standard treatment. Patients treated with the new preoperative treatment demonstrated higher rates of tumor regression and organ preservation. Additionally, chemoradiotherapy-related toxicity and postoperative complications were similar between the two treatment schemes. However, neither treatment strategy prolonged the survival of patients with LARC. This new preoperative treatment strategy should be recommended first for LARC.

Integrated IMRT vs segmented 3D-CRT of the chest wall and supraclavicular region for Breast Cancer after modified Radical Mastectomy: An 8-year follow-up.

Objective: The purpose of this study was to evaluate the efficacy of two radiotherapy techniques for breast cancer patients with post-mastectomy. The intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume was compared with the conventional segmented 3-dimensional conformal radiotherapy undergoing modified radical mastectomy. Materials and methods: Patients who received the two post-mastectomy radiation therapies were retrospectively analyzed. The chest wall and supra/infraclavicular region +/- internal mammary nodes were contoured as a whole planning target volume on the planning computed tomography. We evaluated differences in survival, recurrence, and late side effects between the integrated intensity-modulated radiotherapy group and the conventional segmented group. Results: A total of 223 patients were recruited. The mean follow-up was 104.3 months. Of these patients, 129 received integrated radiotherapy and 94 patients received segmented radiotherapy. The 8-year disease-free survival rates were 86.0% and 73.4% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.022). The 8-year overall survival rates were 91.4% and 86.2% for patients treated with integrated radiotherapy and traditional segmented radiotherapy, respectively (P = 0.530). Multivariate analysis demonstrated that radiotherapy was an independent prognostic factor for disease-free survival. No significant difference was observed in late side-effects between the two groups. Conclusion: Intensity-modulated radiotherapy for treating the chest wall and regional nodes contoured as a whole planning target volume reduces the recurrence rate for post-mastectomy breast cancer patients with tolerable toxicities.

Dosimetric evaluation of integrated IMRT treatment of the chest wall and supraclavicular region for breast cancer after modified radical mastectomy.

To investigate the dosimetric characteristics of irradiation of the chest wall and supraclavicular region as an integrated volume with intensity-modulated radiation therapy (IMRT) after modified radical mastectomy. This study included 246 patients who received modified radical mastectomy. The patients were scanned with computed tomography, and the chest wall (with or without the internal mammary lymph nodes) and supraclavicular region were delineated. For 143 patients, the chest wall and supraclavicular region were combined as an integrated planning volume and treated with IMRT. For 103 patients, conventional treatments were employed with 2 tangential fields for the chest wall, abutting a mixed field of 6-MV x-rays (16Gy) and 9-MeV electrons (34Gy) for the upper supraclavicular region. The common prescription dose was 50Gy/25Fx/5W to 90% of the target volume. The dosimetric characteristics of the chest wall, the supraclavicular region, and normal organs were compared. For the chest wall target, compared with conventional treatments, the integrated IMRT plans lowered the maximum dose, increased the minimum dose, and resulted in better conformity and uniformity of the target volume. There was an increase in minimum, average, and 95% prescription dose for the integrated IMRT plans in the supraclavicular region, and conformity and uniformity were improved. The V30 of the ipsilateral lung and V10, V30, and mean dose of the heart on the integrated IMRT plans were lower than those of the conventional plans. The V5 and V10 of the ipsilateral lung and V5 of the heart were higher on the integrated IMRT plans (p < 0.05) than on conventional plans. Without an increase in the radiation dose to organs at risk, the integrated IMRT treatment plans improved the dose distribution of the supraclavicular region and showed better dose conformity and uniformity of the integrated target volume of the chest wall and supraclavicular region.