Search

Purpose: To explore clinical and dosimetric predictors of acute hematologic toxicity (HT) in cervical cancer patients treated with concurrent chemotherapy and volumetric-modulated arc therapy (VMAT)., Methods and Materials: We retrospectively reviewed the clinical data of 184 cervical cancer patients who had concurrent chemotherapy and VMAT. Hematological parameters were collected during the treatment period. The total pelvic bone (TPB) was delineated retrospectively for dose-volume calculations. To compare the differences between two groups, the normality test findings were used to run a paired-samples t-test or Wilcoxon signed-rank test. Pearson's correlation analysis or Spearman's correlation was used to testing the correlation between the two variables. Binary logistic regression analysis was used to analyze associations between HT and possible risk factors. The receiver operating characteristic curve(ROC) was used to evaluate the best cut-off point for dosimetric planning constraints., Results: The nadir of absolute monocyte count (AMC) was found to be positively correlated with the nadir of absolute white blood cells (WBC) count (r = 0.5378, 95% CI 0.4227-0.6357, P < 0.0001) and the nadir of absolute neutrophil count(ANC) (r = 0.5000, 95% CI 0.3794-0.6039, P < 0.0001). The AMC decreased and increased before the ANC and WBC. In multivariate logistic regression analysis, the chemotherapy regimens and the TPB&#95;V20 were independent risk factors for developing grade ≥ 3 HT. The optimal TPB&#95;V20 cut-off value identified by ROC curves and the Youden test was 71% (AUC = 0.788; 95% CI 0.722-0.845; P value < 0.001)., Conclusions: The changing trend of AMC can be used as an effective predictor for the timing and severity of the ANC/WBC nadirs and prophylactic G-CSF administration. Maintain TPB&#95;V20 < 71% and selecting single-agent cisplatin or carboplatin could significantly reduce grade ≥ 3 HT in cervical cancer patients undergoing concurrent chemoradiotherapy., (© 2022. The Author(s).)

Purpose: To evaluate the sensitivity to set up the uncertainty of VMAT plans in Nasopharyngeal carcinoma (NPC) treatment by proposing a plan robustness evaluation method., Methods: 10 patients were selected for this study. A 2-arc volumetric-modulated arc therapy (VMAT) plan was generated for each patient using Varian Eclipse (13.6 Version) treatment planning system (TPS). 5 uncertainty plans (U-plans) were recalculated based on the first 5 times set-up errors acquired from cone-beam computer tomography (CBCT). The dose differences of the original plan and perturbed plan corresponded to the plan robustness for the structure. Tumor control probability (TCP) and normal tissues complication probability (NTCP) were calculated for biological evaluation., Results: The mean dose differences of D 98% and D 95% (ΔD 98% and ΔD 95% ) of PTVp were respectively 3.30 Gy and 2.02 Gy. The ΔD 98% and ΔD 95% of CTVp were 1.12 Gy and 0.58 Gy. The ΔD 98% and ΔD 95% of CTVn were 1.39 Gy and 1.03 Gy, distinctively lower than those in PTVn (2.8 Gy and 2.0 Gy). The CTV-to-PTV margin increased the robustness of CTVs. The ΔD 98% and ΔD 95% of GTVp were 0.56 Gy and 0.33 Gy. GTVn exhibited strong robustness with little variation of D 98% (0.64 Gy) and D 95% (0.39 Gy). No marked mean dose variations of D mean were seen. The mean reduction of TCP (ΔTCP) in GTVp and CTVp were respectively 0.4% and 0.3%. The mean ΔTCPs of GTVn and CTVn were 0.92% and 1.3% respectively. The CTV exhibited the largest ΔTCP (2.2%). In OARs, the brain stem exhibited weak robustness due to their locations in the vicinity of PTV. Bilateral parotid glands were sensitive to set-up uncertainty with a mean reduction of NTCP (ΔNTCP) of 6.17% (left) and 7.70% (right). The D max of optical nerves and lens varied slightly., Conclusion: VMAT plans had a strong sensitivity to set-up uncertainty in NPC radiotherapy, with increasing risk of underdose of tumor and overdose of vicinal OARs. We proposed an effective method to evaluate the plan robustness of VMAT plans. Plan robustness and complexity should be taken into account in photon radiotherapy., (© 2021. The Author(s).)

Objective: This meta-analysis evaluated the efficacy and safety of accelerated partial breast irradiation versus whole-breast irradiation for early-stage breast cancer after breast-conserving surgery., Materials and Methods: A systematic search of PubMed, Embase, and the Cochrane libraries was performed according to the PRISMA statement the last 10 years to April 7, 2020 to identify the randomized controlled trials of APBI versus WBI for treating patients with early-stage breast cancer. Two independent observers evaluated the identified studies. The obtained data were analyzed using the RevMan 5.3 software., Results: A total of 10 randomized controlled trials involving 15,500 patients with early-stage breast cancer were selected according to the inclusion and exclusion criteria and included in this meta-analysis. In this meta-analysis, we included ten studies that reported local recurrence and found significant differences in local recurrence rates (HR = 1.46; 95% CI 1.20-1.79, P = 0.0002). Further analysis showed that this difference may be related to the choice of treatment methods. No differences in distant metastasis, breast cancer deaths, contralateral breast cancer, disease-free survival, and overall survival rates were observed between WBI and APBI groups. There was no significant difference in late toxicity, cosmetic outcomes and quality of life between the two groups, the compliance and tolerance of the patients were well. Compared to whole breast irradiation, accelerated partial breast irradiation significantly reduced serious (≥ grade 2) early toxicities, especially regarding acute skin toxicity., Conclusions: The analysis showed that patients receiving APBI had a higher local recurrence rate, but no differences in distant metastasis, breast cancer deaths, contralateral breast cancer, disease-free survival, and overall survival rates.

Background: Nearly 50% of new gastric cancer cases and gastric cancer-related deaths worldwide occur in China. No global consensus has been reached about the optimal management of locally advanced gastric cancer. Although the Guidelines for the Diagnosis and Treatment of Gastric Cancer from the National Health Commission of China, which has been updated three times since 2010, explicitly emphasize the necessity of adjuvant chemoradiation, few clinical institutions in China routinely adhere to the recommended radiotherapy guidelines. This study aimed to examine the efficacy, in terms of locoregional control and long-term survival, and the safety of adjuvant radiotherapy using intensity-modulated radiation therapy (IMRT) with concurrent and adjuvant fluoropyrimidine-based chemotherapy for gastric cancer., Methods: This was a retrospective evaluation of 156 patients with high-risk gastric cancer who underwent adjuvant chemoradiotherapy between September 2008 and May 2019. The prescribed planning target volume median dose was 45 Gy in 1.8 Gy daily fractions, and all patients received concurrent and adjuvant fluoropyrimidine-based chemotherapy. Locoregional control, distant metastasis, and overall survival rates were estimated. Clinicopathological characteristics and patterns of failure were retrospectively reviewed to identify factors associated with survival and recurrence., Results: The median follow-up duration was 56 months (range 3-130 months) for all patients. Of the patients, 11 (7.1%) were lost to follow-up, and 49 (31.4%) and 104 (66.7%) had stage II or III disease according to the eighth edition of the American Joint Committee on Cancer tumor-node-metastasis staging criteria. The frequencies of acute grade 3 or 4 gastrointestinal and hematological toxicity were 9.6% and 10.9%, respectively. In total, 152 patients (97.4%) completed the entire chemoradiation regimen. No toxicity-related deaths occurred. Nineteen patients (12.2%) had locoregional recurrence, 26 (16.7%) had distant metastases, and 12 (7.7%) had peritoneal metastasis. The overall survival (OS) rates were 83.5%, 65.0%, and 59.5%, while the disease-free survival rates were 75.1%, 61.0%, and 55.6% at 1, 3, and 5 years, respectively. In the multivariate analysis, age, pathological T stage and lymph node ratio (LNR) were found to be independent predictors of OS., Conclusion: Postoperative concomitant IMRT and chemotherapy were well tolerated, with acceptable toxicities and encouraging locoregional tumor control and long-term survival. The LNR can be used as an important prognostic indicator for OS. Adjuvant chemoradiotherapy should be considered for all patients with a high risk of locoregional recurrence, especially in China.