Hemostatic radiotherapy for bleeding gastrointestinal

Hemostatic radiotherapy is a non-invasive treatment for bleeding gastrointestinal(GI)tumors,promoting tumor shrinkage,blood supply reduction,and fibrotic tissue formation.It is effective in cases where traditional interventions are insufficient or contraindicated and can prevent recurrent bleeding in patients with GI bleeding histories.Hypofractionation schedules are also effective for tumor control and patient compliance.

Dosimetric risk factors for radiation esophagitis in patients with breast cancer following regional nodal radiation

BACKGROUND Radiation esophagitis(RE)is one of the most common clinical symptoms of regional lymph node radiotherapy for breast cancer.However,there are fewer studies focusing on RE caused by hypofractionated radiotherapy(HFRT).AIM To analyze the clinical and dosimetric factors that contribute to the development of RE in patients with breast cancer treated with HFRT of regional lymph nodes.METHODS Between January and December 2022,we retrospectively analysed 64 patients with breast cancer who met our inclusion criteria underwent regional nodal intensity-modulated radiotherapy at a radiotherapy dose of 43.5 Gy/15F.RESULTS Of the 64 patients in this study,24(37.5%)did not develop RE,29(45.3%)developed grade 1 RE(G1RE),11(17.2%)developed grade 2 RE(G2RE),and none developed grade 3 RE or higher.Our univariable logistic regression analysis found G2RE to be significantly correlated with the maximum dose,mean dose,relative volume 20-40,and absolute volume(AV)20-40.Our stepwise linear regression analyses found AV30 and AV35 to be significantly associated with G2RE(P<0.001).The optimal threshold for AV30 was 2.39 mL[area under the curve(AUC):0.996;sensitivity:90.9%;specificity:91.1%].The optimal threshold for AV35 was 0.71 mL(AUC:0.932;sensitivity:90.9%;specificity:83.9%).CONCLUSION AV30 and AV35 were significantly associated with G2RE.The thresholds for AV30 and AV35 should be limited to 2.39 mL and 0.71 mL,respectively.

Hypofractionated and intensity-modulated radiotherapy combined with systemic therapy in metastatic hepatocellular carcinoma:A case report

BACKGROUND Liver cancer treatment is characterized by multidisciplinary participation and coexistence of multiple treatment methods.Hypofractionated and intensity-modulated radiotherapy is a new precise radiotherapy technique applied to the treatment of systemic malignant tumors.There is a lack of understanding of hypofractionated and intensity-modulated radiotherapy combined with systemic therapy in metastatic hepatocellular carcinoma(HCC).CASE SUMMARY We report a case of metastatic HCC treated with hypofractionated and intensity-modulated radiotherapy combined with systemic therapy.A 41-year-old man was diagnosed with metastatic HCC(T3N1M1 stage IVB).Because it was found to be in the late stage of cancer and had already metastasized,it was impossible to undergo surgical treatment.In addition to aggressive comprehensive treatment for the primary lesion,local treatment for metastatic cancer can improve the patient's survival potential.Hypofractionated and intensity-modulated radiotherapy can provide a larger single treatment dose within a shorter overall treatment time,and improve the local control rate of the tumor.Follow-up examination demonstrated that the tumor and metastatic lesions had shrunk after therapy.The treatment has showed good efficacy.The patient survived for 18 months without disease progression and stable disease persisted for>38 months.CONCLUSION Targeted therapy and immunotherapy followed by hypofractionated and intensity-modulated radiotherapy are also effective for advanced metastatic HCC.

Advanced gastric cancer achieving major pathologic regression after chemoimmunotherapy combined with hypofractionated radiotherapy: A case report

BACKGROUND Currently,chemotherapy combined with immunotherapy is the established firstline standard treatment for advanced gastric cancer(GC).In addition,the combination of radiotherapy and immunotherapy is considered a promising treatment strategy.CASE SUMMARY In this report,we present a case of achieving nearly complete remission of highly advanced GC with comprehensive therapies.A 67-year-old male patient was referred to the hospital because he presented with dyspepsia and melena for several days.Based on fluorodeoxyglucose positron emission tomography/computed tomography(FDG PET/CT),endoscopic examination and abdominal CT,he was diagnosed with GC with a massive lesion and two distant metastatic lesions.The patient received mFOLFOX6 regimen chemotherapy,nivolumab and a short course of hypofractionated radiotherapy(4 Gy×6 fractions)targeting the primary lesion.After the completion of these therapies,the tumor and the metastatic lesions showed a partial response.After having this case discussed by a multidisciplinary team,the patient underwent surgery,including total gastrectomy and D2 lymph node dissection.Postoperative pathology showed that major pathological regression of the primary lesion was achieved.Chemoimmuno therapy started four weeks after surgery,and examination was performed every three months.Since surgery,the patient has been stable and healthy with no evidence of recurrence.CONCLUSION The combination of radiotherapy and immunotherapy for GC is worthy of further exploration.

Current role of modern radiotherapy techniques in the management of breast cancer

Breast cancer is the most common type of malignancy in females. Advances in systemic therapies and radiotherapy(RT) provided long survival rates in breast cancer patients. RT has a major role in the management of breast cancer. During the past 15 years several developments took place in the field of imaging and irradiation techniques, intensity modulated RT, hypofractionation and partial-breast irradiation. Currently, improvements in the RT technology allow us a subsequent decrease in the treatment-related complications such as fibrosis and long-term cardiac toxicity while improving the loco-regional control rates and cosmetic results. Thus, it is crucial that modern radiotherapy techniques should be carried out with maximum care and efficiency. Several randomized trials provided evidence for the feasibility of modern radiotherapy techniques in the management of breast cancer. However, the role of modern radiotherapy techniques in the management of breast cancer will continue to be defined by the mature results of randomized trials. Current review will provide an up-to-date evidence based data on the role of modern radiotherapy techniques in the management of breast cancer.

Hypofractionated radiotherapy in the treatment of early breast cancer

Radiotherapy(RT) after tumorectomy in early breast cancer patients is an established treatment modality which conventionally takes 6-7 wk to complete.Shorter RT schedules have been tested in large multicentre randomized trials and have shown equivalent results to that of standard RT(50 Gy in 25 fractions) in terms of local tumor control,patient survival and late post-radiation effects.Some of those trials have now completed 10 years of follow-up with encouraging results for treatments of 3-4 wk and a total RT dose to the breast of 40-42.5 Gy with or without boost.A reduction of 50% in treatment time makes those RT schedules attractive for both patients and health care providers and would have a significant impact on daily RT practice around the world,as it would accelerate patient turnover and save health care resources.However,in hypofractionated RT,a higher(than the conventional 1.8-2 Gy) dose per fraction is given and should be managed with caution as it could result in a higher rate of late postradiation effects in breast,heart,lungs and the brachial plexus.It is therefore advisable that both possible dose inhomogeneity and normal tissue protection should be taken into account and the appropriate technology such as three-dimensional/intensity modulated radiation therapy employed in clinical practice,when hypofractionation is used.

Stereotactic radiotherapy for prostate cancer:A review and future directions

Prostate cancer affects over 200000 men annually in the United States alone.The role of conventionally fractionated external beam radiation therapy (RT) is well established as a treatment option for eligible prostate cancer patients; however,the use of stereotactic body radiotherapy (SBRT) in this setting is less well defined.Within the past decade,there have been a number of studies investigating the feasibility of SBRT as a potential treatment option for prostate cancer patients.SBRT has been well studied in other disease sites,and the shortened treatment course would allow for greater convenience for patients.There may also be implications for toxicity as well as disease control.In this review we present a number of prospective and retrospective trials of SBRT in the treatment of prostate cancer.We focus on factors such as biochemical progression-free survival,prostate specific antigen (PSA) response,and toxicity in order to compare SBRT to established treatment modalities.We also discuss future steps that the clinical community can take to further explore this new treatment approach.We conclude that initial studies examining the use of SBRT in the treatment of prostate cancer have demonstrated impressive rates of biochemical recurrencefree survival and PSA response,while maintaining a relatively favorable acute toxicity profile,though long-term follow-up is needed.

Radiotherapy Intensified by Increase of Fraction Size Using Three-Dimensional Conformal Radiotherapy in Bladder Preservation Therapy

Purpose: The impact of radiotherapy on bladder cancers heightened by increase of fraction size using three-dimensional conformal radiotherapy (3DCRT) was verified with biologically effective dose (BED, Gy10). Method: Twenty-five patients who were considered unsuitable for total cystectomy underwent 3DCRT between 2009 and 2014. When a gross tumor volume (GTV) did not neighbor guts and the patient was cooperative to radiotherapy (radical), the GTV was treated with a fraction size of ≥3.0 Gy, while a clinical target volume (CTV) of a whole bladder and lymph nodes at small pelvis were treated with a conventional fraction size of 2.0 Gy. When a GTV neighbored guts (palliative), only a CTV was treated with an increased fraction size of 2.5 Gy. Results: Compared to conventional two-dimensional radiotherapy, BED increased to 62.3 - 77.0 Gy10 (radical) or to 56.1 - 68.0 Gy10 (palliative) but the treatment period shortened to 4 - 5 weeks. Acute adverse events (≤3 months), determined by common terminology criteria for adverse events, were Grade 2 at most, but late adverse events were not observed. Only one patient (6%) lost the bladder. Conclusions: Patients who receive bladder preservation therapy appear good candidates to intensify impact of radiotherapy with 3DCRT.

Intensity Modulated Radiotherapy (IMRT) in the Planning of Hypofractionated Treatment in Head and Neck Tumors

Head and neck cancer (HNCC) is the sixth most common cancer with an incidence of approximately 600,000 cases per year and 300,000 annual deaths worldwide1y2. In Cuba, cancer of the larynx is the fourth cause in incidence, being the fourth cause of cancer death in men. Radiotherapy constitutes an important modality in the control of these tumors and the Intensity Modulated Radiotherapy (IMRT) is a new advance in this field. With it, it is possible to improve dose distribution, decreasing the dose in adjacent healthy tissues and escalating dose in tumor. In this work we present 33 patients of National Institute of Oncology and Radiobiology in Cuba (INOR), in whom the IMRT was used as a treatment technique with a hypofractionation of the dose. Their response was observed at the end of the treatment and one month later. 56% (19) of the patients had a complete response to treatment at the primary site of the tumor and neck. 10% (3) had no response, progressed. 11 of the patients had no response at the lymph node site at the end of treatment, 8 of these 11 had complete remission one month after radiotherapy ended.

Assessment of contralateral mammary gland dose in the treatment of breast cancer using accelerated hypofractionated radiotherapy

AIM:To measure the dose distribution,related to the treatment planning calculations,in the contralateral mammary gland of breast cancer patients treated with accelerated hypofractionated 3-dimensional conformal radiotherapy.METHODS:Thirty-four prospectively selected female patients with right breast cancer (pN0,negative surgical margins) were treated with breast-conserving surgery.A total dose of 42.5 Gy (2.66 Gy/fraction) was prescribed;it was requested that planning target volumes be covered by the 95% isodose line.The contralateral mam-mary gland was defined on CT simulation.The dose received was evaluated by dose volume histograms.RESULTS:The measured contralateral breast doses were:(1) Dose maximum:290-448 cGy [Equivalent (Eq) 337-522 cGy];(2) Mean dose:45-70 cGy (Eq 524815 cGy);and (3) Median dose:29-47 cGy (337-547 cGy) for total primary breast dose of 42.5 Gy in 16 equal fractions.The spearman rho correlation showed statistical significance between the contralateral breast volume and maximum dose (P=0.0292),as well as mean dose (P=0.0025) and median dose (P=0.046) to the breast.CONCLUSION:Minimizing the dose to the contralateral breast has to be one of the priorities of the radiation oncologist when using short schedules because of the radiosensitivity of this organ at risk.Further study is necessary to assess the long-term clinical impact of this schedule.

Hypofractionated versus Conventionally Fractionated Radiotherapy in Post-Mastectomy Breast Cancer Patients

Background & Objective: Hypofractionation has been used in curative setting in breast conservative surgery, but still no adequate information about its application in the adjuvant setting after mastectomy in breast cancer patients. The aim of this trial was to assess the efficacy and toxicity of hypofractionation radiotherapy (40 Gy in 15 fractions) in post mastectomy breast cancer patients and to compare these results with those of post mastectomy patients treated retrospectively by conventional radiotherapy (50 Gy in 25 fractions) as regard overall survival (OS), disease free survival (DFS), locoregional disease free survival (LDFS), and toxicities. Patients & Methods: One hundred post mastectomy breast cancer patients were included into this study, they were divided into 2 groups, the 1st included 50 patients treated prospectively with hypofractionated radiotherapy regimen (40 Gy in 15 fractions), and the 2nd (control group) included 50 patients treated retrospectively with conventionally fractionated radiotherapy regimen (50 Gy in 25 fractions). Results: The 2 year overall survival were 96% & 94% respectively (p = 0.7), while the disease free survival were 91% & 89.8%, respectively (p = 0.9), and the LDFS were 95.8% & 93.3%, respectively (p = 0.9), G1 acute dermatitis was observed in 22 (44%) & 25 (50%) patients in group I & II respectively, G2 in 8 (16%) & 10 (20%) patients respectively, no G4 skin toxicity was detected. Radiation pneumonitis was observed in 2 patients (4%) only in group II. Conclusion: post-mastectomy hypofractionated radiation therapy achieved comparable survival and toxicity to the conventionally fractionated radiotherapy with the advantage of reducing overall treatment time, treatment burden & cost.

Effects of Hypofractionated and Standard Fractionated Irradiation of Mice Heads with Gamma-Rays and Protons on Their Pheripheral Blood Parameters and Behavior

Experiments were performed to study the action of fractionated irradiation of mice heads with γ-rays and protons on their peripheral blood parameters and behavior by the ＂Open Field＂ test. Mice were irradiated in two variants of fractionated irradiation： （1） traditional fractionation （in radiation therapy）： 2 Gy once a day, 5 times a week, the total radiation dose 20 Gy; （2） extreme hypofractionation： 10 Gy once a week, on Mondays, the total radiation dose 20 Gy. The results of the study showed that irradiation of mice heads has no effect on their peripheral blood parameters in both variants of the applied fractionated irradiation and the behavior of mice does not depend on the type of ionizing radiation and the variant of fractionated exposure that we used. On the basis of these results it can be concluded that the option of extreme hypofractionation we have chosen can successfully replace traditional fractionation, which in some cases is applied when carrying out radiotherapy for treating brain tumors. The application of this type of fractionation can lead to shorter terms of radiotherapy and bigger patient capacity of medical centers that conduct radiotherapy.

A Comparative Study of the Recurrence Rate in Hypofractionated versus Conventional Postmastectomy Radiation in Breast Cancer

Background: Treatment options available for breast cancer are Surgery [Breast conservation surgery (BCS) or Modified radical mastectomy (MRM)];Radiation treatment [Conventional radiation treatment or CRT and Hypofractionated radiation treatment or HRT] and Chemotherapy. In the postmastectomy or post lumpectomy setting, radiotherapy (RT) improves loco-regional control. CRT for breast includes 50 Gy in 25 fractions (2 Gy per fraction) and HRT includes 42.5 Gy in 16 fractions (2.7 Gy per fraction) or extreme hypofractionation like 26 Gy in 5 fractions. Alpha/beta value for breast is less, so HRT is ideal for breast. So, there will be good loco-regional control, without increased normal tissue damage. This study aims to identify recurrence rate and toxicity in breast cancer patients treated using conventional and hypofractionated postmastectomy radiotherapy among Indian population. Primary objective: To assess recurrence rate of disease in breast cancer patients treated using hypofractionated postmastectomy radiation and to compare it with breast cancer patients treated using conventional postmastectomy radiation. Secondary objective: To assess the toxicity in hypofractionation and conventional fractionation arm. Methods: This is a prospective observational study conducted in Department of Radiation Oncology from December 2017 to June 2019. Radically treated breast cancer patients who received radiation treatment either conventional or hypofractionated as one of the treatment modalities were included in the study. Data were collected using a structured proforma, history and physical examination, master file of the patients, lab results and the imaging reports, written informed consent form, ECOG performance status scale (Eastern Cooperative Oncology Group), RTOG (Radiation Therapy Oncology Group) Acute Radiation Morbidity Scoring Schema. Patients were monitored for 18 months to identify recurrence rate and toxicity in each arm. Results and discussion: A total of 241 patients were enrolled into this study, among them 175 patients (73%) were given hypofractionation radiotherapy and 66 patients (27%) were given conventional radiotherapy. In hypofractionation arm, recurrence was found in 14 patients (8%), of which, 3 were local recurrences [chest wall] and 11 were systemic recurrences, while in conventional arm, recurrence was found in 4 patients (6%) and all of them were systemic recurrences. Recurrence rate in hypofractionation arm was 8% and in conventional arm was 6.10%. The Kaplan Meier curve shows no significant difference between the two arms with p value = 0.76. Acute toxicities assessed were dermatitis, esophagitis and pneumonitis. Among acute dermatitis, 4 patients had grade 3 and 2 patients had grade 4 in hypofractionation arm, while in conventional arm, 7 patients had grade 3 and 1 patient had grade 4. Grade 1 and 2 together versus grade 3 and 4 acute dermatitis showed a statistically significant difference between the two arms, with more acute toxicity in the conventional arm. Among acute esophagitis, 1 patient had grade 3 and no patients had grade 4 in hypofractionation arm;while in conventional arm, no grade 3 and grade 4 acute esophagitis were found. Among acute pneumonitis, 2 patients had grade 3 and 1 patient had grade 4 in hypofractionation arm, while in conventional arm, 1 patient had grade 3 and no patients with grade 4 were found. Grade 2 and grade 3 acute lung toxicities were found in patients with central lung distance more than 1.5 cm. Conclusion: It was found that the recurrence rate of hypofractionation radiotherapy was comparable to conventional fractionation radiotherapy. With respect to acute dermatitis, grade 1 and grade 2 were significantly more in conventional than hypofractionation arm. Hypofractionated radiotherapy is an equally effective option to conventional radiotherapy and should be encouraged, especially for developing countries like India where the resource is limited, and the incidence of tumour is high.

GOECP/SEOR radiotheraphy guidelines for non-small-cell lung cancer

Non-small cell lung cancer(NSCLC) is a heterogeneous disease accounting for approximately 85% of all lung cancers. Only 17% of patients are diagnosed at an early stage. Treatment is multidisciplinary and radiotherapy plays a key role in all stages of the disease. More than 50% of patients with NSCLC are treated with radiotherapy(curative-intent or palliative). Technological advancesincluding highly conformal radiotherapy techniques, new immobilization and respiratory control systems, and precision image verification systems-allow clinicians to individualize treatment to maximize tumor control while minimizing treatment-related toxicity. Novel therapeutic regimens such as moderate hypofractionation and advanced techniques such as stereotactic body radiotherapy(SBRT) have reduced the number of radiotherapy sessions. The integration of SBRT into routine clinical practice has radically altered treatment of early-stage disease. SBRT also plays an increasingly important role in oligometastatic disease. The aim of the present guidelines is to review the role of radiotherapy in the treatment of localized, locally-advanced, and metastatic NSCLC. We review the main radiotherapy techniques and clarify the role of radiotherapy in routine clinical practice. These guidelines are based on the best available evidence. The level and grade of evidence supporting each recommendation is provided.

Concurrent use of aromatase inhibitors and hypofractionated radiation therapy

AIM: To retrospectively assess the acute and long-term toxicity using aromatase inhibitors (AI) therapy concurrently with hypofractionated radiotherapy (HFRT) in breast cancer patients. METHODS: From November 1999 to October 2007, 66 patients were treated with breast HFRT and concurrent AI. In 63 patients (95.5%), HFRT delivered a total dose of 32.5 Gy to the whole breast within 5 wk (five fractions, one fraction per week). Other fractionations were chosen in three patients for the patients' personal convenience. A subsequent boost to the tumor bed was delivered in 35 patients (53.0%). Acute toxicities were scored according to the Common Toxicity Criteria for Adverse Events v3. Late toxicity was defined as any toxicity occurring more than 6 mo after completion of HFRT and was scored according to the Late Effects Normal Tissue Task Force-Subjective, Objective, Management and Analytic scale. RESULTS: At the end of the HFRT course, 19 patients (28.8%) had no irradiation-related toxicity. Acute grade 1-2 epithelitis was observed in 46 patients (69.7%). One grade 3 toxicity (1.5%) was observed. With a median follow-up of 34 mo (range: 12-94 mo), 31 patients (47%) had no toxicity, and 35 patients (53%) presented with grade 1-2 fibrosis. No grade 3 or greater delayed toxicity was observed. CONCLUSION: We found that AI was well tolerated when given concurrently with HFRT. All toxicities were mild to moderate, and no treatment disruption was necessary. Further prospective assessment is warranted.

Adjuvant chemotherapy and acute toxicity in hypofractionated radiotherapy for early breast cancer

AIM: To evaluate the effect of chemotherapy to the acute toxicity of a hypofractionated radiotherapy(HFRT) schedule for breast cancer. METHODS: We retrospectively analyzed 116 breast cancer patients with T1, 2N0 Mx. The patients received3-D conformal radiotherapy with a total physical dose of 50.54 Gy or 53.2 Gy in 19 or 20 fractions according to stage, over 23-24 d. The last three to four fractions were delivered as a sequential tumor boost. All patients were monitored for acute skin toxicity according to the European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group criteria. The maximum monitored value was taken as the final grading score. Multivariate analysis was performed for the contribution of age, chemotherapy and 19 vs 20 fractions to the radiation acute skin toxicity.RESULTS: The acute radiation induced skin toxicity was as following: grade Ⅰ 27.6%, grade Ⅱ 7.8% and grade Ⅲ 2.6%. No significant correlation was noted between toxicity grading and chemotherapy(P = 0.154, χ2 test). The mean values of acute toxicity score in terms of chemotherapy or not, were 0.64 and 0.46 respectively(P = 0.109, Mann Whitney test). No significant correlation was also noted between acute skin toxicity and radiotherapy fractions(P = 0.47, χ2test). According to univariate analysis, only chemotherapy contributed significantly to the development of acute skin toxicity but with a critical value of P = 0.05. However, in multivariate analysis, chemotherapy lost its statistical significance. None of the patients during the 2-years of follow-up presented any locoregional relapse.CONCLUSION: There is no clear evidence that chemotherapy has an impact to acute skin toxicity after an HFRT schedule. A randomized trial is needed for definite conclusions.

The Effect of Hypofractionated Radiotherapy on Tumor Control and Survival in Patients with High-Risk Breast Cancer

BACKGROUND Adjuvant radiotherapy is given following surgery in breast cancer patients. Hypofractonated radiotherapy can significantly reduce the waiting time for radiotherapy, working load on machines, patient visits to radiotherapy departments and medical costs. Material and Methods 244 patients with high-risk breast cancer (stage IIB, stage III and stage IA with any of the following criteria: lymphovascular invasion, hormonal receptor negative, young age) who underwent Breast conservative surgery (BCS) or Modified radical mastectomy (MRM) were enrolled in this study. All patients received adjuvant radiotherapy with different hypofractionation schedules either 3900 cGY/13 fractions or 4240 cGY/16 fractions or 4005 cGY/15 fractions using linear accelerator with 6 MV photon beam. Lateral/Medial tangential and Ipsilateral supraclavicular fields were employed and the ipsilateral axilla was also irradiated if required to the same dose with posteroanterior field. Patients were followed every 3 mons for the first 2 years and every 6 mons thereafter. Outcomes were analyzed in terms of tumor control and survival. Results 244 patients with high-risk breast cancer requiring postoperative radiotherapy to the intact breast or chest wall were treated. The mean age was 48 years (range 28 - 69 years). The 5-year locoregional free survival of all patients was 93.8% the local relapse reported in 15 patients (6.2%) 7 patients at site of operated scar & 8 patients at the regional lymph nodes. The median follow up period was 75 months ranged from 49 to 102 months. Distant metastasis free survival was 92.2%, the distant metastasis reported in 19 patients which represent (7.8%) of all patients, median survival is 75 months ranged from 49 to 102 months and overall survival was 88.6%. Conclusion It is concluded that hypofractionated radiotherapy is a simple and effective protocol in patients with high-risk breast cancer regarding tumor control and survival.

Application of biological optimization of hypofractionated radiotherapy post conservative surgery for breast cancer

Objective The aim of the study was to discuss the application of biological optimization and its difference from physical optimization in hypofractionated radiotherapy for breast cancer after conservative surgery.Methods This retrospective study enrolled 15 randomly chosen patients with left-sided breast cancer who received radiotherapy.The volumetric arc therapy(VMAT)technique was used to redesign treatment plans with physical functions(PF)group,biological-physical functions combined(BF+PF and PF+BF)groups,and biological functions(BF)group.The dosimetric differences based on the above four optimization methods were assessed by calculating and analyzing the corresponding dose-volume parameters.Results The target parameters of the four groups differed significantly(P<0.05)except for the conformity index(CI).The tumor control probability(TCP)values in the BF and BF+PF groups were higher than those in the PF and PF+BF groups.Moreover,the dose-volume parameters of the ipsilateral lung in the BF group were less than those of three other groups,while the monitor unit(MU)in the BF group was approximately 16%lower than those of the PF and PF+BF groups.Conclusion Biological functions were useful to increase the equivalent uniform dose(EUD)and TCP values of the target,decrease the dose-volume parameters of the organs-at-risk(OARs),and improve treatment efficiency.

Complete pathological response in locally advanced non-small-cell lung cancer patient: A case report

BACKGROUND Chemotherapy and radiotherapy followed by durvalumab is currently the standard treatment for locally advanced node-positive non-small-cell lung cancer(NSCLC).We describe the case of a patient with locally advanced node-positive NSCLC(LA-NSCLC)treated in a phase II prospective protocol with chemotherapy,accelerated hypofractionated radiotherapy(AHRT)and surgery in the preimmunotherapy era.CASE SUMMARY A 69-year-old male,ex-smoker(20 PY),with a Karnofsky performance status of 90,was diagnosed with locally advanced squamous cell lung carcinoma.He was staged by total body computed tomography(CT)scanning,and integrated 18Ffluorodeoxyglucose positron emission tomography/CT scan[cT4 cN3 cM0,stage IIIC according to TNM(tumor-node-metastasis)8th edition]and received AHRT between chemotherapy cycles,in accordance with the study protocol(EudractCT registration 2008-006525-14).At the end of the study the patient underwent surgery,which was not part of the protocol,and showed a complete pathological response.CONCLUSION This case report confirms that AHRT can be used successfully to treat primary LA-NSCLC with bilateral mediastinal lymph node involvement.Our case is of particular interest because of the pathological response after AHRT and the lack of surgical complications.We hypothesize that this radiotherapeutic approach,with its proven efficacy,could be delivered as a short course reducing treatment costs,increasing patient compliance and reducing toxicity.We are currently investigating the possibility of combining hypofractionation,chemotherapy and immunotherapy for patients with LA-NSCLC.

Estimation of the effect of target and normal tissue sparing based on equivalent uniform dose-based optimization in hypofractionated radiotherapy for lung cancer

Objective This study aims to investigate the dosimetric differences among four planning methods of physical and biological optimization in hypofractionated radiation therapy for non-small cell lung cancer(NSCLC).Methods Ten NSCLC patients receiving radiation therapy were chosen for this retrospective study.Volumetric modulated arc treatment plans for each patient were remade with dose-volume(DV)functions,biological-physical functions,and biological functions,using the same constraint parameters during optimization.The dosimetric differences between the four types of plans were calculated and analyzed.Results For the target,equivalent uniform dose(EUD)of the EUD and EUD+DV groups was approximately 2.8%–3.6%and 3.2%–3.7%higher than those of the DV and DV+EUD groups,respectively.The average tumor control probability(TCP)of the EUD and EUD+DV groups was also significantly higher than those of the other two groups(P<0.05).The difference in heterogeneity index(HI)among the four groups was also statistically significant(P<0.05),while the difference of conformity index(CI)was not significant(P>0.05).For the organs at risk,the differences of EUD,V5,V10,V20,V30 of normal lung tissues were not statistically significant(P>0.05);however,the mean lung dose of the EUD and EUD+DV groups was slightly lower than those of the other two groups.Conclusion The biological optimization method has obvious advantages of improving EUD and TCP of the target,while decreasing the exposed dose of normal lung.This result is meaningful in choosing plan optimization methods in routine work.