Cancer field： A new concept

The proceeding of cancer development seems to be driven by the complex interaction among cells, stroma and adjacent tissue. Here we advocate a new conception, cancer field, to describe the development of cancer, a complex adaptive system. Cancer field may be divided into center of tumor, periphery of tumor and adjacent tissue. The balance of inhibitors and inducers, including the interaction among cancer cells, niche and adjacent tissue, governs the switch of development of cancer field, which mimic embryonic development, a dynamic process of self-organization. The radial component of intra-tumor heterogeneity raises the field change effects in cancer field. Research strategy may be changed from single cancer cell to cancer field, from malignant transform to cancer development biology.

Validation of the TOPAS Monte-Carlo Code of the Off-Field Dose of a 6 MV Synergy Linac

The risk of radiation-induced second cancer and the late tissue loss due to Off-field doses in radiotherapy remain a serious concern. Monte Carlo (MC) simulation is currently one of the most accurate methods for calculating these doses. MC simulation model based on the Particle Simulation Tool (TOPAS) has been developed to simulate the off-field dose of an Elekta Synergy linear accelerator (Linac) emitting 6 MV photons. Measurements were taken in a water phantom using an ionization chamber to validate this model. The Percentage Depth Dose (PDD) at the depth of 0.0, 5.0, 10.0 and 15.0 cm from the beam axis for a 10 × 10 cm2 field size was measured and simulated. Off-field dose profiles at the depth of 1.5 (dmax), 5.0 and 10.0 cm for field sizes of 5 × 5, 10 × 10, 15 × 15, and 20 × 20 cm2 respectively were measured and simulated. Comparison of measured and simulated off-field dose values showed a good agreement. The average gamma passing rate of the PDDs and profiles curves for off-field doses were 87.5% and 98.11% respectively. The local dose difference based on the PDD curve between the measured and simulated was less than 6.0 % for all locations. For all field size considered in this study, the average difference between profile curves for off-field dose measured and simulated was 9.1%. PDDs and Profiles curves for off-field dose simulation uncertainties were less than 2.0% and 1.0% respectively. TOPAS-MC simulation model developed is a good representation of our 6 MV Linac Elekta Synergy for assessing off-field dose, which would be the primary cause of some secondary cancers.

Cancer field surgery for locoregional tumor control of cervical carcinoma

As the current standard,surgery is applied to treat early-stage cervical cancer and selected post-irradiation pelvic relapses.Surgical therapy for local disease is based on a model of unlimited isotropic cancer cell propagation and dissection artifacts such as subperitoneal“ligaments”and“spaces”.For regional disease,the role of traditional surgery is diagnostic and eventually cytoreductive.However,the isotropic local tumor propagation model has to be rejected due to numerous inconsistencies with clinical facts.Likewise,the“ligament and space”approach to the subperitoneum is too crude and variable to accurately cover both local spread and intercalated lymph node metastases of cervical cancer.The ontogenetic cancer field model is fully in line with the locoregional spread patterns of carcinoma of the female genital tract.Developmentally derived(ontogenetic)anatomy enables unbiased and accurate dissection of the complex tissue structures within the subperitoneum.Cancer field surgery founded on these insights has a high potential to improve the treatment outcome of cervical carcinoma.

Targeted treatment of cancer with radiofrequency electromagnetic fields amplitude-modulated at tumor-specific frequencies

In the past century, there have been many attempts to treat cancer with low levels of electric and magnetic fields. We have developed noninvasive biofeedback examination devices and techniques and discovered that patients with the same tumor type exhibit biofeedback responses to the same, precise frequencies. Intrabuccal administration of 27.12 MHz radiofrequency(RF) electromagnetic fields(EMF), which are amplitude-modulated at tumor-specific frequencies, results in long-term objective responses in patients with cancer and is not associated with any significant adverse effects. Intrabuccal administration allows for therapeutic delivery of very low and safe levels of EMF throughout the body as exemplified by responses observed in the femur, liver, adrenal glands, and lungs. In vitro studies have demonstrated that tumor-specific frequencies identified in patients with various forms of cancer are capable of blocking the growth of tumor cells in a tissue- and tumor-specific fashion. Current experimental evidence suggests that tumor-specific modulation frequencies regulate the expression of genes involved in migration and invasion and disrupt the mitotic spindle. This novel targeted treatment approach is emerging as an appealing therapeutic option for patients with advanced cancer given its excellent tolerability. Dissection of the molecular mechanisms accounting for the anti-cancer effects of tumor-specific modulation frequencies is likely to lead to the discovery of novel pathways in cancer.

Inducing Apoptosis of Cancer Cell and Inhibiting Mice's MalignantTumour Growth by Magnetic Fields

It was found that the growth of malignant tumour in mice was inhibited and the ability of immune cell’s dissolving cancer cells was enhanced by ultralow frequency (ULF) pulsed gradient magnetic field. The DNA contents of nuclei decreased which indicated that magnetic field can block DNA replication and mitosis of cancer cells. It was observed that magnetic field inhibited the cancer cell’s metabolism, lowered its malignancy, and restrained its rapid and heteromorphic growth. The morphology properties of Programmed Cell Death (PCD) of the cancer cells of the treated group by magnetic field was observed for the first time. The heterochromatin condensed and coagulated together along the nuclear membrane; the endoplasmic reticulums expanded and fused with the cellular membrane; many apoptotic bodies which were packed by the cellular membrane appeared and were devoured by the lymphocytes and plasma.

Comparative Dosimetric Study for Treating Left Sided Breast Cancer Using Three Different Radiotherapy Techniques:Tangential Wedged Fields, Forward Planned Segmented Filed, and IP-IMRT

Background: Radiation therapy should not only be directed to improve the local control, which has a survival benefit, but also should be directed to minimize the risk of complications, which may develop in critical organs. Several studies have reported that field-in-field (FiF) radiotherapy technique improves the dose homogeneity, decreases doses to lungs, heart and contralateral breast compared with conventional wedged technique. Purpose: compare the dosimetry for the left breast cancer radiotherapy using three different radiotherapy techniques, tangential wedged fields (TW), segmented field (FiF) and inverse planning IMRT (IP-IMRT). Material and Methods: Twenty patients have undergone left breast-conservative surgery and received a prescribed dose of 50 Gy/25 fractions. Results: The mean PTV receiving >105% (V105) dose was1.75% for IP-IMRT, 2.03% for FiF, and 4.82% for TW. The mean V95% was 92.1% for TW, 96% for FiF, and 95.1% for IP-IMRT;these differences regarding V105% and V95% are statistically significant through paired comparison between FiF vs TW and IP-IMRT vs TW, with no statistically significant difference between FiF and IP-IMRT. Better conformity and homogeneity indices for FiF and IMRT compared to TW with statistical significant difference. Regarding organs at risk, left lung and heart have higher values of V5, V10, and V20 for IP-IMRT compared to TW and FiF;the differences are statistically significant, lower coronary artery regionV30 vules for IPIMRT compared to TW and FiF but no difference in the Dmean between IPIMRT and FIF. FiF and TW decrease the contralateral breast dose significantly compared to IP IMRT. Conclusion: FiF technique is an efficient and reliable method for achieving a uniform dose throughout the whole breast resulting in improved coverage, sparing of organs at risk and reduction of acute and late toxicities.

Actinic keratosis and field cancerization

While actinic keratoses(AKs) have been considered precancerous until recently for being able to turn into squamous cell carcinomas(SCCs), it is now agreed that it would be more appropriate to call them cancerous. Although not all AKs turn into SCC and some of them may even have a spontaneous regression, there is an obvious association between SCC and AK. Approximately 90% of SCs have been reported to develop from AKs and AKs are the preinvasive form of SCCs. The presence of two or more AKs on a photodamaged skin is an indicator of field cancerization and represents an increased risk of invasive SCC. All lesions should be treated since it cannot be foreseen which of the lesions will regress and which will progress to SCC. AK can be a single lesion or it can involve multiple lesions in a field of cancerization; thus, AK treatment is grouped under two headings:(1) Lesion-specific treatment; and (2) Field-targeted treatment. Lesion-specific treatments are practicable in patients with a small number of clinically visible and isolated lesions. These treatments including cryotherapy, surgical excision, shave excision, curettage and laser are based on physical destruction of the visible lesions. Field-targeted treatments are effective in the treatment of visible lesions, subclinical lesions and keratinocyte changes in the areas surrounding the visible lesions. Field targeted treatment options are topical imiquimod cream, 5% 5-fluorouracil cream, ingenol mebutate, diclofenac gel, resimiquimod and photodynamic therapy.

薄层小视野非压脂T2WI联合DWI对宫颈癌术前分期的价值

目的:探讨薄层小视野非压脂T2WI联合弥散加权成像(DWI)技术对宫颈癌术前MRI分期诊断的准确性。方法:126例经活检证实的宫颈癌患者纳入研究,术前MRI检查采用薄层小视野非压脂T2WI及DWI序列,以术后病理为对照,计算术前MRI分期的特异度、灵敏度、阴性预测值(NPV)、阳性预测值(PPV)和准确度。采用Kappa检验分析宫颈癌术前MRI分期与术后病理的一致性。结果:MRI分期ⅠB1、ⅠB2、ⅠB3、ⅡA1、ⅡA2和ⅢC1分别为23例、36例、18例、25例、17例和7例,病理分期ⅠB1、ⅠB2、ⅠB3、ⅡA1、ⅡA2和ⅢC1分别为21例、38例、15例、24例、18例和10例。MRI对于宫颈癌ⅠB1、ⅠB2、ⅠB3、ⅡA1、ⅡA2和ⅢC1分期的准确度分别为98.41%、100%、97.62%、94.44%、89.68%和94.44%,总准确度为95.77%,与病理结果有较好的一致性(Kappa值=0.842,P<0.001)。结论:薄层小视野非压脂T2WI联合DWI对宫颈癌术前分期的诊断效能较高,具有临床推广价值。

数字乳腺断层摄影评估新辅助化疗后肿瘤大小的价值

目的评估新辅助化疗后数字乳腺断层摄影(DBT)、全数字化乳腺摄影(FFDM)和超声(US)检查预测残留肿瘤大小的能力。方法回顾性分析2020年1月1日至2021年12月31日病理结果确诊为乳腺癌,行新辅助化疗并接受手术治疗患者的临床及影像学资料。所有患者在新辅助化疗后均行乳腺DBT、FFDM及US检查。采用Pearson相关分析计算不同影像检查方法测量残留肿瘤大小与病理测量结果的相关性;以0.5 cm为阈值,分析不同影像检查预测残留肿瘤大小的准确率。结果85例患者,共86个病灶,去除新辅助化疗后无残留癌的病灶,共纳入72个病灶。新辅助化疗后,DBT、FFDM、US测量残留肿瘤大小与病理测量结果均呈中等程度相关。DBT、FFDM、US预测残留肿瘤大小的准确率分别为59.72%(43/72)、43.06%(31/72)、41.67%(30/72)。DBT与FFDM、US预测残留肿瘤大小的准确率比较,差异具有统计学意义(χ^(2)=4.003、4.695,P=0.045、0.030)。结论新辅助化疗后,DBT预测残留肿瘤大小的准确率优于FFDM与US。DBT在新辅助化疗后的术前评估具有良好的应用前景。

Seeking the Source of Transience for a Unique Magnetic Field Pattern That Completely Dissolves Cancer Cells <i>in Vitro</i>

Purpose: Exposure to a particular pattern of weak (~3 to 5 μT) magnetic fields produced by computer-generated point durations within three-dimensions completely dissolved malignant cancer cells but not healthy cells. Biomolecular analyses and confocal microscopy indicated excessive expansion followed by contraction contributed to the “explosion” of the cell. However, after months of replicable effects, the phenomenon slowly ceased. Considering the potency of the complete dissolution of cancer cell lines after 5 days of 6.5-hour daily exposures and the implications for human treatment, the potential source of the disappearance of the effect was pursued by summarizing all of the 50 experiments and assessing the likely etiologies. Materials and Methods: B16-BL6, MDAMB 231 and MCF7 malignant cells and HSG, a non-malignant cell line, were exposed to a sham-field condition or to a specific pattern of computer-generated magnetic fields produced from converting different voltages, each with point durations of 3 ms to 3-D magnetic fields. Conclusion: The specific serial presentation of the two field patterns (one frequency modulated;the other amplitude and frequency modulated) completely dissolved malignant cells but not normal cells within a “zone” within the exposure volume at the conjunction of the three planes of the applied magnetic fields. The affected cells underwent massive melanin production, expansion, contraction and “beading” of submembrane actin structures before fragmentation within this zone. However, this powerful all-or-none phenomenon may have been disrupted by moving the cells, excess mechanical agitation during exposure, or non-optimal point durations of the field parameters. Indirect effects from communication signals (WIFI) through line currents that operated the incubators could not be excluded.

ZOOMit IVIM-DWI与DKI在鉴别肺癌不同病理类型中的应用价值

目的探讨小视野体素内不相干运动扩散成像(ZOOMit IVIM-DWI)与扩散峰度成像(DKI)的定量参数在区分肺癌不同病理类型中的应用价值。方法选取在山东省立医院经病理证实的95例肺癌患者为观察对象,按照细胞类型将其分为小细胞肺癌(SCLC)和非小细胞肺癌(NSCLC)两组,NSCLC组79例,包括腺癌57例,鳞癌22例,SCLC组16例。纳入的患者术前均具有完整的影像学资料,经手术或穿刺活检获取病理结果。术前行ZOOMit IVIM-DWI及DKI序列扫描,人工勾画感兴趣区,比较肺癌不同病理类型的真实扩散系数(D值)、假扩散系数(D*值)、灌注分数(f值)、平均扩散峰度(MK值)、平均扩散系数(MD值)差异,采用受试者工作特征曲线(ROC)评价各参数的诊断效能。结果NSCLC的D值、f值、MD值大于SCLC,MK值小于SCLC,差异均有统计学意义(P<0.05),各参数鉴别诊断效能曲线下面积大于0.700(P<0.05),其中IVIM-DWI的D值、DKI的MD值分别为0.903、0.912(P<0.001);而腺癌与鳞癌之间各参数值的差异无统计学意义(P>0.05)。IVIM-DWI的D*值在肺癌常见病理类型的鉴别中,差异无统计学意义(P>0.05)。结论ZOOMit IVIM-DWI与DKI在鉴别肺癌病理类型中有一定应用价值,其中DKI的MD值与ZOOMit IVIM-DWI的D值诊断效能高于其它定量参数,并且DKI的MD值的诊断特异性最高。

基于CoMFA方法对氟喹啉-4-酮衍生物的分子建模与设计

基于比较分子力场分析法(CoMFA),建立了16个已知活性的氟喹啉-4-酮衍生物抗肝癌活性(K_(S))的三维定量构效关系(3D-QSAR)模型,并研究该类结构与生物活性之间的关系.CoMFA模型的交叉验证系数(Q^(2))为0.338,拟合验证系数(R^(2))是0.987.此3D-QSAR模型的预测值与实验值基本一致,表明该模型具有显著的统计学可靠性和预测能力.该模型中立体场、静电场贡献率依次为41.9%、58.1%.根据3D-QSAR模型分析结果进行分子设计并完成活性预测,预测结果印证了分析的合理性,为该系列化合物的结构优化提供了合理建议.

单体位联合双体位DBT与FFDM对乳腺癌的诊断价值

目的 探讨单体位[头尾位(craniocaudal, CC)或内外侧斜位(mediolateral oblique, MLO)]数字化乳腺断层合成技术(digital breast tomosynthesis,DBT)联合全视野数字化乳腺X线摄影(full-fild digital mammography,FFDM)检查对乳腺癌的检出率和诊断效能。方法 选取141例乳腺病变患者影像学资料,患者同时行乳腺DBT和FFDM检查。由2位放射科诊断医师分别对患者DBT图像进行单体位和双体位(CC+MLO)阅片并联合FFDM,以病理结果为金标准。分析单体位和双体位DBT检查联合FFDM检查对患者乳腺良恶性病灶的检出率及诊断效能。结果 141例患者按照ACR2013版BI-RADS系统分类标准:a类3例、b类40例、c类84例、d类14例。根据BI-RADS评级标准,2位放射科诊断医师采用四种诊断方式(DBT-CC,DBT-MLO及双体位DBT分别联合FFDM及单独FFDM)进行诊断。结论 采用DBT+FFDM的阅片方式无论是单体位还是双体位的结果假阳性率及假阴性率均低于FFDM,诊断的准确度、特异度及灵敏度均高于FFDM,对高/低年资诊断医师FFDM+DBT双体位的诊断效能高于单体位,在FFDM+DBT-CC和FFDM+DBT-MLO单体位之间准确度、灵敏度和特异度MLO均高于CC位。

疾病高发区饮食行为的社会文化机制研究——以广东省消化道肿瘤为例

以广东省消化道肿瘤高发区——潮汕地区为例,援引路径依赖与场域-惯习理论,应用定量和定性混合研究的方法,从社会文化机制的视角,通过对潮汕人工夫茶与腌制食品饮食习惯的分析,解释为何非健康的地方性饮食行为仍然具有强大的文化惯性。研究认为:潮汕人对工夫茶香味的追求、传统特殊茶艺文化的日常化以及功夫茶所附加的现代社交属性等因素,不断锁定与强化了以热饮为特征的工夫茶品饮方式;民间食用杂咸的传统习俗、快节奏现代生活下对快捷饮食的需求以及本地人对海鲜食材原始风味的追求,是腌制食品在潮汕地区持续风行的直接因素。在潮汕饮食场域中,惯习是一种社会化的主观性,具有强大的无意识、结构化力量。这种社会力量型塑了集体性饮食行为的路径,让社会行动者自觉进入一个自然的、充满意义的生活空间。既往医学或健康地理观点大多聚焦于地理环境、疾病、饮食习惯三者之间的联系,本研究所揭示的饮食行为路径依赖中的社会文化机制,对这种联系的理解具有较好的拓展意义,也有助于为疾病预防提供新的思路和建议。

肿瘤电场治疗在非小细胞肺癌中的研究进展

根据全球癌症统计数据显示,肺癌仍是死亡率最高的恶性肿瘤,其中非小细胞肺癌约占肺癌总数的85%。肿瘤电场治疗是一种安全有效的局部抗肿瘤治疗手段。它可以通过干扰有丝分裂、引起DNA损伤、抑制细胞迁移、增加细胞膜通透性、提高穿透血脑屏障的能力、诱导抗肿瘤免疫等机制发挥抗肿瘤作用,同化疗、放疗、免疫治疗等多种抗肿瘤治疗方法起到协同作用。本文将重点探讨肿瘤电场治疗的作用机制及其在非小细胞肺癌、非小细胞肺癌脑转移中的临床研究,期待为非小细胞肺癌的治疗提供新思路。

r-fov IVIM与r-fov DWI模型参数早期预测乳腺癌新辅助化疗疗效价值的比较

目的 比较磁共振小视野体素不相干运动扩散加权成像(reduced field of view,intravoxel incoherent motion,r-fov IVIM)及小视野常规扩散加权成像(reduced field of view,diffusion weighted imaging,r-fov DWI)模型参数预测乳腺侵润性导管癌新辅助化疗疗效的价值。方法 前瞻性选取28例单侧乳腺浸润性导管癌患者,收集化疗前、化疗2周期后乳腺r-fov IVIM模型参数真性扩散系数(Dt),假性扩散系数(Dp),灌注分数(f);r-fov DWI参数表观扩散系数(ADC)。根据术后病理结果分为组织学非显著反应组13人,组织学显著反应组15人;采用SPSS 25.0对数据进行处理,比较NAC前和化疗2个周期后两组间的参数值差异。绘制受试者工作特征曲线(receiver operating characteristic,ROO曲线分析以上参数对新辅助化疗疗效的预测价值。结果NAC2周期后ADC值,NAC2周期后与NAC前参数差值ΔADC、ΔDt值,三者的曲线下面积(area under curve,AUC)最大(0.951 VS 0.914、0.914),预测MHR组的效能高;NAC2周期后的Dt值,预测MHR组的效能较好(AUC=0.827)。结论 NAC2周期后,r-fov DWI模型参数ADC值和r-fov IVIM模型参数Dt值越高,且较NAC前升高程度越大,新辅助化疗结束后越容易获得较好的疗效;其中,以NAC2周期后,r-fovDWI模型参数ADC值的预测效能最高,应作为乳腺癌浸润性导管癌临床治疗过程中,新辅助化疗反应评估的主要参考参数。

全数字化乳腺钼靶X线用于乳腺癌的早期诊断价值

目的:分析在乳腺癌早期诊断中,应用全数字化乳腺钼靶X线检查的诊断价值。方法:选取2023年1月至2024年1月于福建医科大学附属三明市第一医院接受检查的疑似乳腺癌患者80例,均应用彩色多普勒超声检查、全数字化乳腺钼靶X线检查,将结果与最终临床确诊结果比较,计算并比较两种检查方法的诊断效能。结果:80例疑似乳腺癌患者中,临床确诊62例;全数字化乳腺钼靶X线对早期乳腺癌的检查灵敏度、特异度及准确度均高于彩色多普勒超声,差异具有统计学意义(P<0.05)。全数字化乳腺钼靶X线对原位癌、黏液腺癌、浸润性导管癌、单纯性乳腺癌的检出数与临床确诊结果的差异均无统计学意义(P>0.05)。结论:在早期乳腺癌诊断中,应用全数字化乳腺钼靶X线检查的诊断效能较高,可为患者后续病情诊断及治疗方案的规划提供可靠参考。

基于图像空间重建技术的小视野DWI在直肠癌T分期中的应用价值

目的:探讨基于图像空间重建技术的小视野DWI序列联合常规高分辨率T_(2)WI序列在直肠癌T分期中的应用价值。方法:回顾性分析2022年6月-2022年11月在本院行直肠MRI检查的患者的病例资料。所有患者均使用3.0T MR扫描仪进行检查,行常规高分辨率斜轴位T_(2)WI序列和小视野(rFOV)基于图像空间采样重建(IRIS)技术DWI(rFOV IRIS-DWI)序列扫描。所有图像均由一名从事直肠癌研究方向的影像科高级职称医生进行两轮评估。第一轮评估所有入组患者的斜轴位高分辨率T_(2)WI序列图像,一周后进行第二轮评估,同时观察斜轴位高分辨率T_(2)WI序列图像和rFOV IRIS-DWI序列图像,分别记录两次评估的磁共振T(mrT)分期结果。采用MedCalc统计软件(Version 18.2.1)进行统计学分析。两种诊断方法对病理T(pT)分期的诊断准确性采用Fisher精确概率检验。采用受试者操作特征(ROC)曲线评估两种诊断方法对pT分期的诊断效能。两种诊断方法诊断信心差值符合正态分布采用配对样本t检验,差值不符合正态分布采用配对Wilcoxon秩和检验。以P<0.05为差异具有统计学意义。结果:本研究共纳入27例直肠癌患者,年龄53~81岁,中位年龄69岁,基于rFOV IRIS-DWI联合T_(2)WI序列,分别有1例(6.7%)pT3期病例被低估为mrT1-2期、1例(8.3%)pT1-2病例被高估为mrT3期,MRI对pT1-2、pT3期的诊断准确性分别为91.7%、93.3%,两种序列的诊断准确性差异具有统计学意义(P=0.022)。T_(2)WI、T_(2)WI联合rFOV IRIS-DWI序列诊断pT3期的敏感度、特异度、ROC曲线下面积(AUC)分别为73.3%、58.3%、0.658和93.3%、91.7%、0.928,AUC差异具有统计学意义(P=0.002)。T_(2)WI、T_(2)WI联合rFOV IRIS-DWI序列对所有入组病例的诊断信心分别为2.37、2.9分,差异具有统计学意义(P=0.0002)。结论:rFOV IRIS-DWI联合高分辨率T_(2)WI序列能够明显提高直肠癌的T分期的诊断效能和诊断信心。

Epigenetic changes in colorectal cancer

Epigenetic changes frequently occur in human colorectal cancer.Genomic global hypomethylation,gene promoter region hypermethylation,histone modifications,and alteration of miRNA patterns are major epigenetic changes in colorectal cancer.Loss of imprinting(LOI) is associated with colorectal neoplasia.Folate deficiency may cause colorectal carcinogenesis by inducing gene-specific hypermethylation and genomic global hypomethylation.HDAC inhibitors and demethylating agents have been approved by the FDA for myelodysplastic syndrome and leukemia treatment.Non-coding RNA is regarded as another kind of epigenetic marker in colorectal cancer.This review is mainly focused on DNA methylation,histone modification,and microRNA changes in colorectal cancer.