Technology in Cancer Research & Treatment最新文献

IntroductionTo investigate the efficacy of a knowledge-based planning (KBP) model in optimizing dose distribution, and identify the inter-institutional variation in radiotherapy of recurrent nasopharyngeal carcinoma (rNPC).MethodsA total of 70 rNPC patients treated with intensity-modulated radiotherapy (IMRT) were recruited to build a KBP model. Following model refinement, 36 patients were retrospectively enrolled for dosimetric comparison between manually optimized and KBP-generated plans. Ten experienced physicists from six different institutions were engaged to independently design manual plan for a representative case, to assess inter-institutional variations, and differences between KBP and manual plans.ResultsThe refined KBP model provided significant reduced dose in brainstem D_1cc (the dose received by the "hottest"1 cm³ volume, 41.14 ± 8.51 Gy vs 38.48 ± 8.60 Gy, P < 0.001) and spinal cord D_1cc (17.48 ± 9.38Gy vs 12.23 ± 6.56Gy, P < 0.001). In addition, The mean dose (D_mean) of brainstem, spinal cord, mandible, parotid, temporomandibular joint and inner ear were statistically decreased (P < 0.05). In validation cohort, KBP model eliminated the hotspot (0.57 ± 0.01% vs 0.00 ± 0.00%, P < 0.001), improved target homogeneity (HI: 0.06 ± 0.00 vs 0.08 ± 0.00, P < 0.001), and performed superior to the manual plans in sparing organs. While all institutions achieved comparable target coverage, manual plans exhibited substantial variability in sparing brainstem. KBP implementation reduced inter-institutional dose disparities for brainstem (46.30 ± 10.08 Gy vs 41.80 ± 5.80 Gy, P = 0.041) and spinal cord (26.08 ± 7.06 Gy vs 18.19 ± 1.98 Gy, P = 0.002). Additionally, planning efficiency increased by 48.7% (39 vs 76 min).ConclusionsThis KBP framework optimized rNPC reirradiation from three dimensions: 1) Enhanced OARs' protection; 2) Improved target homogeneity; 3) Improved the multi-institutional consistency and efficiency of planning. These advancements established a clinically actionable paradigm for precision reirradiation.

BackgroundEndometrial carcinoma (EC) represents a unique clinical challenge. Fertility-sparing treatments rely on achieving complete response (CR) through progesterone-based therapy. We sought to investigate the prognostic value of molecular subtyping and immunohistochemical (IHC) markers in predicting three-month treatment outcomes and recurrence in EC patients undergoing fertility-sparing therapy.MethodsA retrospective cohort of 68 patients diagnosed with early-stage EC received hysteroscopic surgery and conservative treatment whose paraffin-embedded tissue blocks preserved in our hospital between Jan. 2010 and Oct. 2022 was evaluated. Molecular subtyping based on TCGA classification identified low copy-number (CNL), microsatellite instability-high (MSI-H), and copy-number high (CNH) subtypes. IHC markers, including PTEN, PIK3CA, β-catenin, ARID1A, estrogen receptor (ER), and progesterone receptor (PR) were analyzed for their association with CR and recurrence. Transcriptome sequencing gene chips were used to study patients who achieved or did not achieve CR after three months, those who experienced recurrence within one year, and those who did not recur within two years. Differential genes were then mapped to KEGG pathways to explore the underlying mechanisms of progesterone therapy efficacy.ResultsAmong the 68 patients classified through TCGA molecular typing, 65 cases (95.6%) were CNL subtype, two (2.9%) were MSI-H subtype, and one (1.5%) was CNH subtype. Following a three-month treatment, the CR rate for the CNL subtype was 75.4% (49/65), the MSI-H subtype was 50.0% (1/2), and the CNH subtype was 0% (0/1). In CNL subtype endometrial carcinoma, individuals with high PTEN and PR expression were more likely to achieve CR after three months (P < .05). Conversely, those with elevated CA199 levels and increased PIK3CA expression were more prone to recurrence after CR.ConclusionMSI-H and p53-mutant subtypes of endometrial carcinoma are not suitable for fertility preservation therapy. PTEN/PI3K-AKT-mTOR pathway activation contributes to reduced progesterone sensitivity, underscoring the need for targeted therapeutic strategies to improve patient outcomes.

IntroductionThe utility and application of endocervical curettage (ECC) during colposcopy remain controversial. This study optimized ECC application for primary human papillomavirus (HPV) screening in patients with high-risk (HR)-HPV.MethodsThis retrospective study included patients with HR-HPV, who underwent subsequent cervical biopsy and ECC from January 1, 2014, to December 31, 2020. Logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs). The prediction model was presented as a nomogram and evaluated for discrimination and calibration.ResultsThe additional detection rate of cervical intraepithelial neoplasia 2 + lesions with ECC was 2.0% (77/3887) in patients with HR-HPV. In multivariate risk factor analysis, HPV 16 infection presented a high risk of positive ECC, followed by HPV 33, HPV 58, and HPV 31. Irrespective of the abnormal cytopathological results, positive ECC was significantly increased (all P < .001). Females with acetowhite changes on colposcopy, transformation zone (TZ) type II, TZ type III, colposcopic impression of high-grade squamous intraepithelial lesion, or cancer were at a high risk of positive ECC. The final prediction model included significant variables from risk factor analysis, and had excellent calibration and classification capabilities, with an area under the receiver operating curve of 0.902 (95% CI, 0.881-0.922). Additionally, calibration analysis suggested consistency.ConclusionAs the additional detection value of ECC is limited. A satisfactory prediction model was designed to optimize ECC application in patients with HR-HPV infection.

Low temperature plasma (LTP), as an emerging cancer treatment technology, has shown significant therapeutic potential due to its unique physical and chemical properties and biological effects. This article reviews the basic characteristics of LTP and its multiple mechanisms of application in tumor treatment. LTP can induce various cell death modes, including apoptosis, pyroptosis, and autophagy, through its unique chemical and physical properties. Additionally, studies have demonstrated that the combination of LTP with traditional chemotherapy drugs (such as cisplatin and paclitaxel) can enhance the anti-tumor efficacy of the drugs while reducing drug resistance. The combined application of LTP and nanomaterials also shows promising prospects. However, LTP still faces some challenges and limitations in medical applications. Future research needs to further explore the specific applications of LTP in different tumor types, optimize treatment plans, and develop more portable and efficient LTP devices to promote its application in clinical treatment.

IntroductionThe role of radiotherapy (RT) in de novo metastatic breast cancer (dnMBC) patients undergoing surgery remains controversial due to limited evidence. This study aimed to evaluate the impact of postoperative radiotherapy on survival outcomes in this population.Materials and methodsWe retrospectively analyzed 102 dnMBC patients who underwent surgery at a provincial cancer hospital. Patients were grouped based on whether they received postoperative RT. Baseline characteristics were compared using the chi-square test. Kaplan-Meier analysis and Cox proportional hazards models were used to assess the prognostic impact of postoperative radiotherapy on local recurrence-free survival (LRFS), progression-free survival (PFS), and overall survival (OS).ResultsKM survival analysis showed that postoperative RT significantly improved LRFS (HR = 0.3634, 95%CI 0.1552-0.8508, p = .0197) and PFS (HR = 0.4903, 95%CI 0.3061-0.7855, p = .003) but had no significant effect on OS (HR = 0.7337, 95%CI 0.3514-1.508, p = .5395). Multivariate analysis identified postoperative RT as an independent protective factor for LRFS (HR = 0.265, 95%CI 0.088-0.795, p = .018) and PFS (HR = 0.525, 95%CI 0.313-0.882, p = .015). Subgroup analysis showed that for LRFS, RT had no significant interaction with different subgroup classification variables (all interaction p > .05). However, RT had a significant interaction with N stage for PFS (p = .016), specifically in N1-3 patients (HR = 0.384, 95% CI 0.221-0.668).ConclusionRT may improve disease control in selected dnMBC patients undergoing surgery, particularly those with lymph node metastasis. However, these findings still require further validation in larger, multicenter cohorts.

Background: Current evidence from evidence-based medicine is limited regarding the efficacy and safety of immunotherapy in elderly patients aged 75 years and older with malignant solid tumors. PRaG therapy, which combines PD-1/PD-L1 inhibitors, radiotherapy, and granulocyte-macrophage colony-stimulating factor (GM-CSF), aims to treat patients with advanced, refractory tumors. Preliminary findings indicate that patients aged 75 years and older can benefit from this treatment and can tolerate it well. Objective: This study aims to evaluate the efficacy and safety of the PRaG regimen in elderly patients with advanced malignant solid tumors to provide evidence-based support for immunotherapy in this population. Methods and Analysis: This study involves a multicenter, prospective, single-arm phase II clinical trial designed to enroll 29 patients aged 75 years and older with either newly diagnosed or recurrent metastatic advanced solid tumors that are histologically confirmed. All of the eligible patients will have had to receive at least two cycles of PRaG therapy until disease progression or intolerable adverse effects occurred. The study protocol was approved on September 12, 2023, by the Ethics Committee of the Second Affiliated Hospital of Soochow University (JD-LK-2023-082-I01) and by the ethics committees of all of the participating centers (Trial Registration Number: NCT06112041).

Objective: To investigate the optimal radiotherapy regimen for synchronous bilateral breast cancer (SBBC) by utilizing dosimetric and radiobiological indicators, and to assess the impact of applying an optical surface monitoring system(OSMS) on the precision of SBBC radiotherapy treatment.

Methods: Nine patients with SBBC who underwent breast-conserving radiotherapy were retrospectively selected. Four treatment plans were designed for each patient using the Versa HD (Elekta, Stockholm) accelerator: single-isocenter intensity-modulated radiotherapy/volumetric modulated arc therapy(IMRT-ISO1/VMAT-ISO1) and dual-isocenter IMRT/VMAT(IMRT-ISO2/VMAT-ISO2), with a prescription dose of 42.4 Gy in 16 fractions. Dosimetric parameters and radiobiological impact were measured for the target and organs at risk(OARs). The monitoring log files of three SBBC patients were analyzed to quantitatively assess real-time delta shifts encompassing six degrees of freedom (DOFs) during intrafraction and interfraction treatment processes.

Results: Compared to both the IMRT techniques, the VMAT techniques offered superior target conformity, uniformity, and dose fall-off capability. Among the four treatment plans, VMAT-ISO1 exhibited optimal performance by significantly reducing radiation exposure volume to OARs while maintaining exceptional precision in dose delivery and execution efficiency. The tumor control probability (TCP) was exceeded by 98.5% for all four modalities. According to the OSMS logs, the maximum absolute error in translational motion during the treatment of three SBBC patients was predominantly manifested along the vertical(VRT) axis, with an mean value of 2.2 mm. Additionally, it was observed that the coronal plane (YAW) exhibited the largest error in terms of rotational angle, with an mean deviation of 1.1°.

Conclusions: The VMAT-ISO1 technique demonstrates apparent dosimetric and radiobiological advantages in SBBC radiotherapy, ensuring precise dose delivery and shortening treatment durations. The accuracy of SBBC radiotherapy is ensured by OSMS through pre-treatment positioning correction and real-time monitoring throughout the treatment process.

IntroductionEarly identification of patients at risk for toxicity induced by radiotherapy (RT) is essential for developing personalized treatments and mitigation plans. Preclinical models with relevant endpoints are critical for systematic evaluation of normal tissue responses. This study aims to determine whether attention-based vision transformers can classify MR images of irradiated and control mice, potentially aiding early identification of individuals at risk of developing toxicity.MethodC57BL/6J mice (n = 14) were subjected to 66 Gy of fractionated RT targeting the oral cavity, swallowing muscles, and salivary glands. A control group (n = 15) received no irradiation but was otherwise treated identically. T2-weighted MR images were obtained 3-5 days post-irradiation. Late toxicity in terms of saliva production in individual mice was assessed at day 105 after treatment. A pre-trained vision transformer model (ViT Base 16) was employed to classify the images into control and irradiated groups.ResultsThe ViT Base 16 model classified the MR images with an accuracy of 69%, with identical overall performance for control and irradiated animals. The ViT's model predictions showed a significant correlation with late toxicity (r = 0.65, p < 0.01). One of the attention maps from the ViT model highlighted the irradiated regions of the animals.ConclusionsAttention-based vision transformers using MRI have the potential to predict individuals at risk of developing early toxicity. This approach may enhance personalized treatment and follow-up strategies in head and neck cancer radiotherapy.

BackgroundGamma Knife radiosurgery has proven to be highly effective for small brain lesions and those with a limited number of metastases. This study aimed to evaluate the treatment outcome of Gamma Knife radiosurgery in Vietnamese breast cancer patients with brain metastasis.MethodsThis retrospective descriptive study included 75 patients treated between January 2019 and December 2023. Eligible patients had 1 to 5 brain lesions ≤ 3 cm, a Karnofsky Performance Status (KPS) score of ≥ 60, and no prior whole-brain radiotherapy or brain tumor resection. Clinical characteristics were documented, and imaging responses were evaluated using RECIST criteria. Overall survival (OS), brain-specific progression-free survival (BSPFS), and overall response rates were analyzed using Kaplan-Meier survival curves and Cox regression.ResultsSeventy-five patients were included in the study, with a median follow-up time of 15.9 months. The median age was 53.0 years (range: 29-73 years), and 39 patients (52%) were HER2-positive. The median total tumor volume per patient was 3.78 cm³. A total of 152 brain tumors were identified, of which 131 (86.2%) were <2 cm in diameter, 36 patients (48.0%) had a single lesion. The intracranial tumor control rates were 96% at 3 months and 92.5% at 6 months. The median overall survival (OS) was 17.2 months (range: 13.7-20.7 months). Multivariate analysis revealed that the total volume of metastatic lesions ≤7.0 cm³, hormone receptor negativity, ≤ 3 lines of systemic treatment before brain metastasis and controlled extracranial metastases were correlated with both BSPFS and OS.ConclusionGamma Knife radiosurgery is an effective treatment for limited brain metastases, demonstrating a high rate of local control over brain lesions, which contributed to the promising survival outcome in Vietnamese breast cancer patients.

Purpose: To evaluate the impact of patient setup errors on the dosimetry and radiobiological models of intensity-modulated radiotherapy (IMRT) for esophageal cancer.

Methods and materials: This retrospective study with 56 patients in thermoplastic mask (TM) and vacuum bag (VB) groups utilized real setup-error (RSE) data from cone-beam CT scans to generate simulated setup-error (SSE) data following a normal distribution. The SSE data were applied to simulate all treatment fractions per patient by shifting the plan isocenter and recalculating the dose. A simulated plan sum (SPS) was created by accumulating all simulated fraction plans. Comparisons of target dose, improved homogeneity index (iHI), conformity index (CI), tumor control probability (TCP) and normal tissue complication probability (NTCP) were conducted between SPSs and original treatment plans (OTPs). Correlations between RSE and TCP/NTCP were analyzed.

Results: Compared to OTPs in the TM group, the planning target volume (PTV) of SPSs showed reductions in D_95%, D_98%, iHI, CI and TCP by 1.2%, 2.2%, 2.3%, 7.3% and 1.2%, while D_2% increased by 0.3%; D_2% of clinical target volume (CTV) increased by 0.2% (P < .05). In the VB group, D_95%, D_98%, iHI, CI and TCP of PTV decreased by 2.5%, 4.5%, 4.2%, 15.6% and 2.0%, with D_2% increasing by 0.5%; D_2% of CTV increased by 0.5% while D_98% decreased by 0.2% (P < .05). The dose of organs at risk (OARs) changed slightly in both groups. The mean and standard deviation of absolute RSE negatively correlated with the TCP of PTV, while the mean RSE positively correlated with the NTCP of lung and spinal cord.

Conclusions: Setup errors may reduce dose homogeneity and conformity, potentially reducing TCP of PTV and increasing NTCP, especially when mean RSE shifts the isocenter towards OARs. VB immobilization may result in relatively larger impacts of setup errors, but this needs future validation.