Diffusion-weighted imaging and variable flip angle T1 mapping: a supplement for image-guided biopsy in follow-up analysis of liver fibrosis

Purpose To evaluate the performance of diffusion-weighted imaging(DWI) and variable flip angle(VFA) T1 mapping as a supplement to image-guided biopsy in follow-up analysis of liver fibrosis. Materials and Methods This prospective study was approved by the institution's committee on human research, and written informed consent was provided from the enrolled patients. We investigated five MRI parameters of DWI and VFA T1 mapping, collected from 11 patients who underwent serial ultrasound image-guided biopsy with follow-up MRI within 1.5 years after treatment for liver fibrosis/cirrhosis. For each patient, four consecutive MRI examinations were conducted, including baseline MRI before treatment and three follow-up MRI examinations after treatment at each 0.5-year interval. ADC values at four b values and T1 relaxation times were correlated to pathology-confirmed liver fibrosis stages, which were subsequently divided into two groups, stages F2–3 and F4. The receiver operating characteristic(ROC) analysis and repeated measurement analysis of variance were used for statistical analysis. Results Among these ADC parameters, ADC value(b = 500 s/mm^2) was the most consistent in differentiating between stage F2–3 and F4 liver fibrosis. Repeated measurement analysis showed that the intra-group and inter-group differences were 0.447 and 0.024, respectively. T1 relaxation time could not consistently differentiate between the F2–3 and F4 groups; however, it was repeatable, and the intra-group and inter-group differences were 0.410 and 0.042, respectively. Conclusion MRI-ADC value at a b value of 500 s/mm^2 can be a promising biomarker for differentiating stages F2–3 and F4 liver fibrosis. A combination of this biomarker with repeatable T1 relaxation time may function as a non-invasive tool for follow-up liver fibrosis in patients who reject repeated image-guided biopsy.

Recent advances of multimoda ultrasound in image-guided prostate-targeted biopsy

Prostate-targeted biopsy is usually the preferred method over systematic biopsy because it can effectively detect prostate cancer using only a few puncture cores with fewer complications.With the development of ultrasound,it has gained multimodal technological upgrades,such as the emergence of contrast-enhanced ultrasound,ultrasound elastography,and three-dimensional ultrasonography.Moreover,multimodal ultrasound has played an increasingly significant role in prostate-targeted biopsies.

Effectiveness of Histopathological Examination of Ultrasound-guided Puncture Biopsy Samples for Diagnosis of Extrapulmonary Tuberculosis

Objective To evaluate the diagnostic value of histopathological examination of ultrasound-guided puncture biopsy samples in extrapulmonary tuberculosis(EPTB).Methods This study was conducted at the Shanghai Public Health Clinical Center.A total of 115patients underwent ultrasound-guided puncture biopsy,followed by MGIT 960 culture(culture),smear,Gene Xpert MTB/RIF(Xpert),and histopathological examination.These assays were performed to evaluate their effectiveness in diagnosing EPTB in comparison to two different diagnostic criteria:liquid culture and composite reference standard(CRS).Results When CRS was used as the reference standard,the sensitivity and specificity of culture,smear,Xpert,and histopathological examination were(44.83%,89.29%),(51.72%,89.29%),(70.11%,96.43%),and(85.06%,82.14%),respectively.Based on liquid culture tests,the sensitivity and specificity of smear,Xpert,and pathological examination were(66.67%,72.60%),(83.33%,63.01%),and(92.86%,45.21%),respectively.Histopathological examination showed the highest sensitivity but lowest specificity.Further,we found that the combination of Xpert and histopathological examination showed a sensitivity of 90.80%and a specificity of 89.29%.Conclusion Ultrasound-guided puncture sampling is safe and effective for the diagnosis of EPTB.Compared with culture,smear,and Xpert,histopathological examination showed higher sensitivity but lower specificity.The combination of histopathology with Xpert showed the best performance characteristics.

Percutaneous ultrasound-guided coaxial core needle biopsy for the diagnosis of multiple splenic lesions: A case report

BACKGROUND The overlap of imaging manifestations among distinct splenic lesions gives rise to a diagnostic dilemma.Consequently,a definitive diagnosis primarily relies on his-tological results.The ultrasound(US)-guided coaxial core needle biopsy(CNB)not only procures sufficient tissue to help clarify the diagnosis,but reduces the incidence of puncture-related complications.CASE SUMMARY A 41-year-old female,with a history of pulmonary tuberculosis,was admitted to our hospital with multiple indeterminate splenic lesions.Gray-scale ultrasono-graphy demonstrated splenomegaly with numerous well-defined hypoechoic ma-sses.Abdominal contrast-enhanced computed tomography(CT)showed an en-larged spleen with multiple irregular-shaped,peripherally enhancing,hypodense lesions.Positron emission CT revealed numerous abnormal hyperglycemia foci.These imaging findings strongly indicated the possibility of infectious disease as the primary concern,with neoplastic lesions requiring exclusion.To obtain the precise pathological diagnosis,the US-guided coaxial CNB of the spleen was ca-rried out.The patient did not express any discomfort during the procedure.CONCLUSION Percutaneous US-guided coaxial CNB is an excellent and safe option for obtaining precise splenic tissue samples,as it significantly enhances sample yield for exact pathological analysis with minimum trauma to the spleen parenchyma and sur-rounding tissue.

Circulating tumor DNA in liquid biopsy: Current diagnostic limitation

With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great potential to become an important part of precision medicine.cfDNA is the total amount of free DNA in the systemic circulation,including DNA fragments derived from tumor cells and all other somatic cells.Tumor cells release fragments of DNA into the bloodstream,and this source of cfDNA is called circulating tumor DNA(ctDNA).cfDNA detection has become a major focus in the field of tumor research in recent years,which provides a new opportunity for non-invasive diagnosis and prognosis of cancer.In this paper,we discuss the limitations of the study on the origin and dynamics analysis of ctDNA,and how to solve these problems in the future.Although the future faces major challenges,it also con-tains great potential.

Liquid biopsy for gastric cancer:Techniques,applications,and future directions

After the study of circulating tumor cells in blood through liquid biopsy(LB),this technique has evolved to encompass the analysis of multiple materials originating from the tumor,such as nucleic acids,extracellular vesicles,tumor-educated platelets,and other metabolites.Additionally,research has extended to include the examination of samples other than blood or plasma,such as saliva,gastric juice,urine,or stool.LB techniques are diverse,intricate,and variable.They must be highly sensitive,and pre-analytical,patient,and tumor-related factors significantly influence the detection threshold,diagnostic method selection,and potential results.Consequently,the implementation of LB in clinical practice still faces several challenges.The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases,monitoring treatment response,early identification of relapses,or assessing patient risk.On the other hand,gastric cancer(GC)is a disease often diagnosed at advanced stages.Despite recent advances in molecular understanding,the currently available treatment options have not substantially improved the prognosis for many of these patients.The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients.In this comprehensive review,from a pathologist’s perspective,we provide an overview of the main options available in LB,delve into the fundamental principles of the most studied techniques,explore the potential utility of LB application in the context of GC,and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

Changes in macrophage infiltration and podocyte injury in lupus nephritis patients with repeated renal biopsy: Report of three cases

BACKGROUND In this study,we retrospectively analysed macrophage infiltration and podocyte injury in three patients with diffuse proliferative lupus nephritis(LN)who un-derwent repeated renal biopsy.CASE SUMMARY Clinical data of three diffuse proliferative LN patients with different pathological characteristics(case 1 was LN IV-G(A),case 2 was LN IV-G(A)+V,and case 3 was LN IV-G(A)+thrombotic microangiopathy)were reviewed.All patients underwent repeated renal biopsies 6 mo later,and renal biopsy specimens were studied.Macrophage infiltration was assessed by CD68 expression detected by immunohistochemical staining,and an immunofluorescence assay was used to detect podocin expression to assess podocyte damage.After treatment,Case 1 changed to LN III-(A),Case 2 remained as type V LN lesions,and Case 3,which changed to LN IV-S(A),had the worst prognosis.We observed reduced macro-phage infiltration after therapy.However,two of the patients with active lesions after treatment still showed macrophage infiltration in the renal interstitium.Before treatment,the three patients showed discontinuous expression of podocin.Notably,the integrity of podocin was restored after treatment in Case 1.CONCLUSION It may be possible to reverse podocyte damage and decrease the infiltrating ma-crophages in LN patients through effective treatment.

Core needle biopsy for thyroid nodules assessment-a new horizon?

Ultrasound-guided fine-needle aspiration is the standard for evaluating thyroid nodules with a high safety profile and a relatively low number of non-diagnostic cytological findings.Nevertheless,this diagnostic method traditionally has its weak points.Several diagnostic categories such as BethesdaⅠ,ⅢandⅣare not reliable for thyroid carcinoma risk assessment.Recent advancements in a core needle biopsy made it possible to use this tool as a new method for thyroid nodules evaluation.The main feature of this method is the use of thin needles(18-21G)and guns with an automatic trigger mechanism.The histological material collected with the use of a core needle biopsy is usually superior to cytological.Therefore,the core needle biopsy can be used as a complementary technique to a standard fine needle aspiration in difficult and dubious cases of thyroid neoplasia with uncertain malignant potential.

Liver biopsy in the post-hepatitis C virus era in Japan

In Japan,liver biopsies were previously crucial in evaluating the severity of hepatitis caused by the hepatitis C virus(HCV)and diagnosing HCV-related hepatocellular carcinoma(HCC).However,due to the development of effective antiviral treatments and advanced imaging,the necessity for biopsies has significantly decreased.This change has resulted in fewer chances for diagnosing liver disease,causing many general pathologists to feel less confident in making liver biopsy diagnoses.This article provides a comprehensive overview of the challenges and potential solutions related to liver biopsies in Japan.First,it highlights the importance of considering steatotic liver diseases as independent conditions that can coexist with other liver diseases due to their increasing prevalence.Second,it emphasizes the need to avoid hasty assumptions of HCC in nodular lesions,because clinically diagnosable HCCs are not targets for biopsy.Third,the importance of diagnosing hepatic immune-related adverse events caused by immune checkpoint inhibitors is increasing due to the anticipated widespread use of these drugs.In conclusion,pathologists should be attuned to the changing landscape of liver diseases and approach liver biopsies with care and attention to detail.

Exploring kidney biopsy findings in congenital heart diseases:Insights beyond cyanotic nephropathy

BACKGROUND The association between congenital heart disease and chronic kidney disease is well known.Various mechanisms of kidney damage associated with congenital heart disease have been established.The etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis(FSGS),however,this has only been demonstrated in case reports and not in observational or clinical trials.AIM To identify baseline and clinical characteristics,as well as the findings in kidney biopsies of patients with congenital heart disease in our hospital.METHODS This is a retrospective observational study conducted at the Nephrology Depart-ment of the National Institute of Cardiology“Ignacio Chávez”.All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the study.RESULTS Ten patients with congenital heart disease and kidney biopsy were found.The average age was 29.00 years±15.87 years with pre-biopsy proteinuria of 6193 mg/24 h±6165 mg/24 h.The most common congenital heart disease was Fallot’s tetralogy with 2 cases(20%)and ventricular septal defect with 2(20%)cases.Among the 10 cases,one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found,receiving specific treatment after histopathological diagnosis,delaying the initiation of kidney replacement therapy.Among remaining 8 cases(80%),one case of FSGS with perihilar variety was found,while the other 7 cases were non-specific FSGS.CONCLUSION Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement therapy.In 2 out of 10 patients in our study,interventions were performed,and initiation of kidney replacement therapy was delayed.Prospective studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease.

Indications for Renal Needle Biopsy and Histological Spectrum of Kidney Disease in Togo

Introduction: The frequent late-stage diagnosis of chronic kidney disease (CKD) constrains the treatment choices for nephrologists. Renal biopsy (RB) is crucial for accurately identifying renal lesions. This key nephrological procedure, however, is invasive and not without potential complications. The purpose of this study was to evaluate the indications, frequency, and histological lesion profiles of renal biopsies in Togo. Materials and Methods: We conducted a descriptive cross-sectional study encompassing all renal biopsies performed in Togo from the inception of nephrology services to the present. Data were compiled from the medical records of the patients. Results: From 2015 to 2023, 68 high-quality renal biopsies were executed in Togo. The patients had an average age of 30.6 years, with a predominance of males (69.1%). The most common indication was nephrotic syndrome, accounting for 66.2% of cases. Histologically, glomerulopathies were predominant, representing 61.8% of lesions, followed by vascular nephropathies (25%) and tubulointerstitial nephropathies (13.2%). The most frequently observed primary glomerulopathy was focal segmental glomerulosclerosis (FSGS). Gross hematuria was the sole complication, occurring in 1.4% of the cases. Conclusion: RB is an evolving practice in Togo. Glomerulopathies are the most commonly observed lesions. The histological categorization of renal lesions is vital for clinicians in their diagnostic reasoning and approach.

Emerging role of liquid biopsy in rat sarcoma virus mutated metastatic colorectal cancer:A case report

BACKGROUND In patients with metastatic colorectal cancer(mCRC),the treatment options are limited and have been proved to be affected by rat sarcoma virus(RAS)mutational status.In RAS wild-type(wt)patients,the combination of antiepidermal growth factor receptor(EGFR)monoclonal antibodies with chemotherapy(CT)is more effective than CT alone.On the other hand,RAS-mutated patients are not eligible for treatment with anti-EGFR antibodies.CASE SUMMARY Eleven patients with initially RAS-mutated mCRC were followed from diagnosis to May 2022.At the time of cell-free DNA determination,five patients had undergone one CT line,five patients had undergone two CT lines,and one patient had undergone three CT lines(all in combination with bevacizumab).At the second and third treatment lines[second line(2L),third line(3L)],patients with neo-RAS wt received a combination of CT and cetuximab.In neo-RAS wt patients treated with anti-EGFR,our findings indicated an increase in progression-free survival for both 2L and 3L(14.5 mo,P=0.119 and 3.9 mo,P=0.882,respectively).Regarding 2L overall survival,we registered a slight increase in neo-RAS wt patients treated with anti-EGFR(33.6 mo vs 32.4 mo,P=0.385).At data cut-off,two patients were still alive:A RAS-mutated patient undergoing 3L treatment and a neo-RAS wt patient who received 2L treatment with anti-EGFR(ongoing).CONCLUSION Our case series demonstrated that monitoring RAS mutations in mCRC by liquid biopsy may provide an additional treatment line for neo-RAS wt patients.

Endoscopic ultrasound-guided deep and large biopsy for diagnosis of gastric infiltrating tumors with negative malignant endoscopy biopsies

AIM: To assess the diagnostic yield and safety of adeep and large biopsy technique under the guidance of endoscopic ultrasound(EUS) for diagnosis of gastric infiltrating tumors with negative malignant endoscopy biopsies.METHODS: From January 2009 to March 2014, 36 patients in whom gastric infiltrating tumors had been diagnosed by EUS received negative results for malignancy after endoscopic biopsies. The deep and large biopsy technique combined bite-on-bite technique with or without endoscopic mucosal resection(EMR) to obtain submucosal tissue from lesions. EUS was used to select the appropriate biopsy sites. If the lesion protruded into the cavity, EMR was performed for removal of the overlying mucosa and then bite-onbite technique was conducted in the resected area to obtain submucosal tissue. If the lesion appeared to be flat or was difficult to lift by injection, the bite-on-bite technique was directly used.RESULTS: Twenty-eight of the 36 patients were treated by EMR followed by bite-on-bite technique, while 8 patients only underwent bite-on-bite technique. Histological results showed 23 of the 36 lesions were poorly differentiated adenocarcinomas, 2 diffuse large B cell lymphomas, 4 mucosa-associated lymphoid tissue-type lymphomas, and 7 undiagnosed. The deep and large biopsy technique provided a definitive and conclusive diagnosis in 29(80.6%) of the 36 patients. The 12 gastric linitis plastica and 6 lymphoma patients received chemotherapy and avoided surgery. Minor oozing of blood in 2 mucosal resection wounds was managed by argon plasma coagulation and in 5 cases after deep biopsies by epinephrine(0.001%). Neither severe hemorrhage nor perforation occurred in any patient.CONCLUSION: The deep and large biopsy technique is superior to ordinary endoscopic biopsy for achieving an accurate diagnosis of gastric infiltrating tumors.This procedure guided by EUS is an effective and safe diagnostic method for gastric infiltrating tumors in which endoscopic biopsy results were negative for malignancy.

Progress in image-guided radiotherapy for the treatment of non-small cell lung cancer

Lung cancer is one of the most common malignant tumors. It has the highest incidence and mortality rate of all cancers worldwide. Late diagnosis of nonsmall cell lung cancer(NSCLC) is very common in clinical practice, and most patients miss the chance for radical surgery. Thus, radiotherapy plays an indispensable role in the treatment of NSCLC. Radiotherapy technology has evolved from the classic two-dimensional approach to three-dimensional conformal and intensity-modulated radiotherapy. However, how to ensure delivery of an accurate dose to the tumor while minimizing the irradiation of normal tissues remains a huge challenge for radiation oncologists, especially due to the positioning error between fractions and the autonomous movement of organs. In recent years, image-guided radiotherapy(IGRT) has greatly increased the accuracy of tumor irradiation while reducing the irradiation dose delivered to healthy tissues and organs. This paper presents a brief review of the definition of IGRT and the various technologies and applications of IGRT. IGRT can help ensure accurate dosing of the target area and reduce radiation damage to the surrounding normal tissue. IGRT may increase the local control rate of tumors and reduce the incidence of radio-therapeutic complications.

Spinal cord biological safety of image-guided radiation therapy versus conventional radiation therapy

Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three months after radiation, neuronal injury at the T9-10 levels was observed, including reversible injury induced by spinal image-guided radiation therapy and apoptosis induced by conventional radiation therapy. The number of apoptotic cells and expression of the proapoptotic protein Fas were significantly reduced, but expression of the anti-apoptotic protein heat shock protein 70 was significantly increased after image-guided radiation therapy compared with the conventional method of the same radiation dose. Moreover, the spinal cord cell apoptotic index positively correlated with the ratio of Fas/heat shock protein 70. These findings indicate that 3 months of radiation therapy can induce a late response in the spinal cord to radiation therapy; image-guided radiation therapy is safer and results in less neuronal injury compared with conventional radiation therapy.

Image-guided lens extraction surgery: a systematic review

A systematic review of the recent literature regarding the current image-guided systems used for cataract surgery or refractive lens exchange was performed based on the PubMed and Google Scholar databases in March 2018. Literature review returned 21 eligible studies. These studies compared image-guided systems with other keratometric devices regarding their accuracy, repeatability and reproducibility in measurement of keratometric values, astigmatism magnitude and axis, as well as in IOL power calculation. Additionally, the image-guided systems were compared with conventional manual ink-marking techniques for the alignment of toric IOLs. In conclusion, image-guided systems seem to be an accurate and reliable technology with measurements of high repeatability and reproducibility regarding the keratometry and IOL power calculation, but not yet interchangeable with the current established and validated keratometric devices. However, they are superior over the conventional manual inkmarking techniques for toric IOL alignment.

Real-time fluorescence image-guided gastrointestinal oncologic surgery:Towards a new era

Technological improvements are crucial in the evolution of surgery.Real-time fluorescence-guided surgery(FGS)has spread worldwide,mainly because of its usefulness during the intraoperative decision-making processes.The success of any gastrointestinal oncologic resection is based on the anatomical identification of the primary tumor and its regional lymph nodes.FGS allows also to evaluate the blood perfusion at the gastrointestinal stumps after colorectal or esophageal resections.Therefore,a reduction on the anastomotic leak rates has been postulated as one of the foreseeable benefits provided by the use of FGS in these procedures.Although the use of fluorescence in lymph node detection was initially described in breast cancer surgery,the technique is currently applied in gastric or splenic flexure cancers,as they both present complex and variable lymphatic drainages.FGS allows also to perform intraoperative lymphograms or sentinel lymph node biopsies.New applications of FGS are being developed to assist in the detection of peritoneal metastases or in the evaluation of the tumor resection margins.The present review aims to provide a general overview of the current status of real-time FGS in gastrointestinal oncologic surgery.We put a special focus on the different applications of FGS,discussing the main findings and limitations found in the contemporary literature and also the promising near future applications.

Percutaneous ultrasound and endoscopic ultrasound-guided biopsy of solid pancreatic lesions: An analysis of 1074 lesions

Backgrounds:Percutaneous ultrasound(US)and endoscopic ultrasound(EUS)-guided pancreatic biopsies are widely accepted in the diagnosis of pancreatic diseases.Studies comparing the diagnostic performance of US-and EUS-guided pancreatic biopsies are lacking.This study aimed to evaluate and compare the diagnostic yields of US-and EUS-guided pancreatic biopsies and identify the risk factors for inconclusive biopsies.Methods:Of the 1074 solid pancreatic lesions diagnosed from January 2017 to February 2021 in our center,275 underwent EUS-guided fine needle aspiration(EUS-FNA),and 799 underwent US-guided core needle biopsy(US-CNB/FNA).The outcomes were inconclusive pathological biopsy,diagnostic accuracy and the need for repeat biopsy.All of the included factors and diagnostic performances of both USCNB/FNA and EUS-FNA were compared,and the independent predictors for the study outcomes were identified.Results:The diagnostic accuracy was 89.8%for EUS-FNA and 95.2%for US-CNB/FNA(P=0.001).Biopsy under EUS guidance[odds ratio(OR)=1.808,95%confidence interval(CI):1.083-3.019;P=0.024],lesion size<2 cm(OR=2.069,95%CI:1.145-3.737;P=0.016),hypoechoic appearance(OR=0.274,95%CI:0.097-0.775;P=0.015)and non-pancreatic ductal adenocarcinoma carcinoma(PDAC)diagnosis(OR=2.637,95%CI:1.563-4.449;P<0.001)were identified as factors associated with inconclusive pathological biopsy.Hypoechoic appearance(OR=0.236,95%CI:0.064-0.869;P=0.030),lesions in the uncinate process of the pancreas(OR=3.506,95%CI:1.831-6.713;P<0.001)and non-PDAC diagnosis(OR=2.622,95%CI:1.278-5.377;P=0.009)were independent predictors for repeat biopsy.Biopsy under EUS guidance(OR=2.024,95%CI:1.195-3.429;P=0.009),lesions in the uncinate process of the pancreas(OR=1.776,95%CI:1.014-3.108;P=0.044)and hypoechoic appearance(OR=0.127,95%CI:0.047-0.347;P<0.001)were associated with diagnostic accuracy.Conclusions:In conclusion,both percutaneous US-and EUS-guided biopsies of solid pancreatic lesions are safe and effective;though the diagnostic accuracy of EUS-FNA is inferior to US-CNB/FNA.A tailored pancreatic biopsy should be considered a part of the management algorithm for the diagnosis of solid pancreatic disease.

A novel technique for sacropelvic fixation using image-guided sacroiliac screws:a case series and biomechanical study

In this study, we sought to assess the safety and accuracy of sacropelvic fixation performed with image-guided sacroiliac screw placement using postoperative computed tomography and X-rays. The sacroiliac screws were placed with navigation in five patients. Intact specimens were mounted onto a six-degrees-of-freedom spine motion simulator. Long lumbosacral constructs using bilateral sacroiliac screws and bilateral S1 pedicle and iliac screws were tested in seven cadaveric spines. Nine sacroiliac screws were well-placed under an image guidance system(IGS);one was placed poorly without IGS with no symptoms. Both fixation techniques significantly reduced range of motion(P<0.05) at L5-S1. The research concluded that rigid lumbosacral fixation can be achieved with sacroiliac screws,and image guidance improves its safety and accuracy. This new technique of image-guided sacroiliac screw insertion should prove useful in many types of fusion to the sacrum, particularly for patients with poor bone quality,complicated anatomy, infection, previous failed fusion and iliac harvesting.

Biological effects of human lung cells MRC-5 in CBCT positioning for image-guided radiotherapy

Image-guided radiotherapy(IGRT) provides precise positioning for the tumor target, but it may bring extra irradiation dose in the target positioning with a cone beam CT(CBCT) which has been increasingly used in IGRT. In this work, we focused on biological effects of the low-dose irradiation in IGRT, which have not been considered so far. Primary human fibroblasts cells from the lung and MRC-5 were irradiated by a CBCT. DNA doublestrand breaks(c-H2 AX foci) and micronucleus frequency of the irradiated samples were analyzed. Compared to the control, the c-H2 AX foci yields of the samples irradiated to 16 m Gy increased significantly, and the micronuclei rate of the samples irradiated for 3 days increased notably. The dose by imaging guidance device can be genotoxic to normal tissue cells, suggesting a potential risk of a secondary cancer. The effects, if confirmed by clinical studies,should be considered prudentially in designing IGRT treatment plans for the radiosensitive population, especially for children.