Performance of an offline systematic error correction strategy in pediatric patients receiving adjuvant conformal radiotherapy for Wilm's tumor.

BACKGROUND: Radiotherapy plays a key role as an adjuvant treatment in pediatric Wilm's tumor, improving both survival and quality of life. The success of radiotherapy depends on the precise delivery of radiation dose to the tumor while sparing radiosensitive structures in the vicinity of the tumor. Pediatric patients pose unique challenges in achieving accurate radiotherapy delivery due to their inability to understand instructions and the high radiosensitivity of their tissues. Thus, it is important to determine the optimum geometric verification strategy that will ensure accurate delivery of the prescribed target as specified in the patient's treatment plan. PURPOSE: To evaluate the performance of an offline geometric correction strategy in ensuring accuracy and reproducibility during radiotherapy delivery in Wilm's tumor patients. MATERIAL AND METHODS: The extended no-action level offline correction strategy was applied in the radiotherapy delivery of 45 Wilm's tumor patients. Gross errors from the first three fractions were used to calculate the mean errors which were then applied as offline correction factors. Mean errors among different groups were compared using a two-way analysis of variance (ANOVA) and Dunnett's pairwise comparisons. All statistical analyses and data visualization were performed using GraphPad Prism version 7 (Insight Partners, GraphPad Holdings, LLC). RESULTS: A total of 45 patients were included in the study. In all three orthogonal directions, the recorded gross errors were significantly lower after the application of the systematic error corrections. Random errors were significantly larger in the longitudinal direction compared to lateral (mean difference = 0.28, p = 0.036) and vertical directions (mean difference = 0.37 cm, p = 0.003). Patients' age was a significant predictor of random errors whereby the magnitude of random error decreased with increasing age. CONCLUSION: This study shows that the offline correction strategy used is effective in ensuring the accuracy of radiotherapy delivery in pediatric Wilm's tumor patients.

Delayed diagnostic evaluation of symptomatic breast cancer in sub-Saharan Africa: A qualitative study of Tanzanian women.

BACKGROUND: Women with breast cancer in sub-Saharan Africa are commonly diagnosed at advanced stages. In Tanzania, more than 80% of women are diagnosed with stage III or IV disease, and mortality rates are high. This study explored factors contributing to delayed diagnostic evaluation among women with breast cancer in Tanzania. METHODS: A qualitative study was performed at Muhimbili National Hospital in Dar es Salaam, Tanzania. Twelve women with symptomatic pathologically proven breast cancer were recruited. In-depth, semi-structured interviews were conducted in Swahili. Interviews explored the women's journey from symptom recognition to diagnosis, including the influence of breast cancer knowledge and pre-conceptions, health seeking behaviors, psychosocial factors, preference for alternative treatments, and the contribution of culture and norms. Audio-recorded interviews were transcribed and translated into English. Thematic analysis was facilitated by a cloud-based qualitative analysis software. RESULTS: All women reported that their first breast symptom was a self-identified lump or swelling. Major themes for factors contributing to delayed diagnostic presentation of breast cancer included lack of basic knowledge and awareness of breast cancer and misconceptions about the disease. Participants faced barriers with their local primary healthcare providers, including symptom mismanagement and delayed referrals for diagnostic evaluation. Other barriers included financial hardships, fear and stigma of cancer, and use of traditional medicine. The advice and influence of family members and friends played key roles in healthcare-seeking behaviors, serving as both facilitators and barriers. CONCLUSION: Lack of basic knowledge and awareness of breast cancer, stigma, financial barriers, and local healthcare system barriers were common factors contributing to delayed diagnostic presentation of breast cancer. The influence of friends and family also played key roles as both facilitators and barriers. This information will inform the development of educational intervention strategies to address these barriers and improve earlier diagnosis of symptomatic breast cancer in Tanzania.

Hyaluronic Acid-Modified Nanoparticles Self-Assembled from Linoleic Acid-Conjugated Chitosan for the Codelivery of miR34a and Doxorubicin in Resistant Breast Cancer.

In this study, a chitosan-based, self-assembled nanosystem that codelivered microRNA34a (miR34a) and doxorubicin (Dox) with hyaluronic acid (HA) modification (named CCmDH NPs) was developed to reverse the resistance of breast cancer (BCa) cells to Dox. The CCmDH NPs had a diameter of 180 ± 8.3 nm and a ζ potential of 16.5 mV with a slow-release effect for 96 h. The codelivery system could protect miR34a from nuclease and serum degradation and transport miR34a and Dox into drug-resistant MCF-7/A cells. In addition, the CCmDH NPs could inhibit proliferation and promote apoptosis by regulating the protein expression of B-cell lymphoma-2 (Bcl-2) and poly(ADP-ribose) polymerase (PARP) and inhibit invasion, metastasis, and adhesion by regulating E-cadherin, N-cadherin, MMP2, CD44, and Snail molecules. The CCmDH NPs induced a 73.7% tumor reduction in xenograft tumor growth in nude mice in vivo. This study provides evidence for the anticancer activity of CCmDH NPs carrying Dox and miR34a in BCa, especially metastatic Dox-resistant BCa models.

Design and screening of a novel neuropilin-1 targeted penetrating peptide for anti-angiogenic therapy in glioma.

AIMS: This study aimed to design and screen a dual functional fusion peptide that could penetrate the blood-brain barrier and target neuropilin 1 (NRP1) overexpressed in vascular endothelial cells for the anti-angiogenesis of glioma treatment. MAIN METHODS: At the cellular level, the in vitro anti-angiogenic activity of six NRP1 targeting peptides was screened by testing the ability to inhibit the proliferation and tube formation of HUVECs. Then, the in vitro anti-angiogenic activity of two fusion peptides containing different linkers was screened by testing the ability to inhibit HUVECs proliferation, tube formation and migration. The effect of fusion peptide on VEGFR2 related signal pathway was confirmed by Western-blotting. Surface plasmon resonance technology was used to detect the affinity of the fusion peptide to NRP1. The ability of FITC-labeled peptides to penetrate cells was confirmed by cell uptake assay. By establishing an orthotopic glioma model, we evaluated the ability of FITC-labeled peptides to penetrate the blood-brain barrier and their anti-glioma growth activity in vivo. KEY FINDINGS: We found that NRP1 targeting peptide RP7 and linker cysteine were the most suitable key components in the fusion peptide. We also found that the fusion peptide Tat-C-RP7 we constructed had the strongest ability to penetrate the blood-brain barrier and anti-angiogenic activity in vitro and in vivo. SIGNIFICANCE: At present, NRP1 targeting peptide as a drug delivery tool and molecular probe seems to have received more attention. We constructed a fusion peptide Tat-C-RP7 with strong anti-angiogenic activity for the treatment of glioma.

Electrolytes supplementation can decrease the risk of nephrotoxicity in patients with solid tumors undergoing chemotherapy with cisplatin.

BACKGROUND: Cisplatin is an important drug in the treatment of various Cancers. However, this drug causes nephrotoxicity that is linked to electrolyte derangement. The aim of this study was to evaluate the effect of electrolyte supplementation in reducing kidney injury in patients receiving cisplatin-based regimen. METHODS: This was non-randomized interventional study conducted at Ocean Road Cancer Institute (ORCI) among patients with confirmed solid tumors. Patients who received cisplatin-based chemotherapy at a dose of ≥50 mg with intravenous normal saline supplemented with Magnesium, Calcium and Potassium (triple electrolyte supplementation) were compared with those who received cisplatin-based chemotherapy with normal saline alone. The patients were followed up for 4 weeks and serum creatinine was measured at every visit. Nephrotoxicity was defined as serum creatinine elevation > 1.5 times that at baseline. RESULTS: A total of 99 patients were recruited, whereby 49 patients (49.5%) received electrolyte supplementation (treatment group) and 50 patients (51.5%) did not receive electrolyte supplementation (control group). The incidence risk of nephrotoxicity was 20.41% (n = 10) in the treatment group and 54% (n = 27) in the control group. Patients in the control group were 2.6 times more likely to experience nephrotoxicity as compared to treatment group [Relative Risks (RR); 2.6, 95%CI; 1.5-4.9, P < 0.0001]. The most common malignancy was cervical cancer, n = 43 (87.8%) in treatment group and n = 45 (90.0%) in the control group (P = 0.590). The Kaplan-Meier analysis and the log-rank test revealed that electrolytes supplementation was associated with extended survival with less nephrotoxicity incidences [P = 0.0004; Hazard ratio (HR) 0.3149; 95% CI 0.165 to 0.6011]. CONCLUSIONS: Electrolytes supplementation decreases the risk of nephrotoxicity after chemotherapy with cisplatin. A randomized controlled trial with a larger sample size is recommended to evaluate the robustness of these findings.