ABSTRACT
Objective:To test the usefulness of PET-range verification (RV) method for proton radiation accuracy verification in poly (methyl methacrylate) (PMMA) phantom using off-line PET/CT scanning.Methods:Proton irradiation dose of 2 Gy and 4 Gy were delivered in PMMA phantom. Given the difference of clinical target volume (CTV), 7 subgroups with different depth (5.0, 7.5, 10.0, 12.5, 15.0, 17.5, 20.0 cm) were set for each dose (14 radiation plans or radiation fields). PET/CT scan was performed 10 min after irradiation of 48-221 MeV proton beam. A co-registration between CT from treatment planning system and PET/CT was performed, as well as the smoothing and normalization of PET/CT data. The region of interest (ROI) and profile lines were drawn with the Raystation PET-RV software. The predictive induced radioactivity and the measured induced radioactivity profile lines were analyzed to evaluate the Δ R50, namely, the error at the position corresponding to 50% of the maximum predictive induced radioactivity at the end of both curves. Results:The size of each ROI was 5.0 cm×5.0 cm×2.5 cm. Profile lines were evenly distributed with the interval of 3 mm, and totally 289 pairs of profile lines were drew. The 2 Gy- and 4 Gy-dose groups yielded similar mean depth errors (Δ R50 between 1 mm and -1 mm with a standard deviation <1 mm). Conclusions:The off-line PET/CT scanning of PMMA phantom reveals a good agreement between predicted and measured PET data, with error of ±1 mm. The PET-RV method can be extended to clinical cases′ verification in human body treatment with further investigation.
ABSTRACT
Objective:To investigate the dosimetric difference between glioma patients treated by particle (proton+ carbon ion) and photon radiotherapy.Methods:Twelve previously-treated glioma patients were selected, and given with the same total dose of 60.00 Gy [RBE]. Two types of planning target volumes (PTVs) including PTV-ion and PTV-photon were expended from clinical target volumes according to range uncertainty and patient setup errors. Based on PTV-ion, proton plans with sequential carbon ion boost (particle plan) were created. Following the same prescription, two types of photon intensity-modulated radiotherapy (IMRT) plans were established to achieve similar target coverage and compare the dose of organs at risk.Results:Target coverages of three types of plans had no statistical difference (all P>0.05). The median integral dose of normal brain of all patients receiving particle plan was merely 44.90% of the minimum number from photon plans ( P<0.001). Compared with the minimum number from photon plans, particle radiotherapy decreased the mean dose of brain stem[(6.83±6.22) Gy[RBE] vs. (15.10±10.11) Gy[RBE], P=0.001)], the maximum dose of chiasm[(47.76±20.80) Gy[RBE] vs. (49.59±20.52) Gy[RBE], P=0.009)] and the mean dose of contralateral hippocampus (0.26±9.08) Gy[RBE] vs. (16.28±11.14) Gy[RBE], P=0.002), respectively. Conclusions:Particle radiotherapy can achieve similar target coverage while maintaining lower normal tissue doses to the photon radiotherapy. Photon planion can increase the doses to adjuvant normal tissues.
ABSTRACT
Objective To evaluate the short-term efficacy and toxicities of intensity-modulated carbon ion radiotherapy (IMCT) for patients with locoregionally recurrent nasopharyngeal carcinoma after intensity-modulated radiotherapy (IMRT).Methods A total of 112 patients with locoregionally recurrent nasopharyngeal carcinoma undergoing salvaging IMCT between May 2015 and February 2018were enrolled in the study.All patients previously received one course of definitive X-ray IMRT.Among them,10 patients (9％) were diagnosed with stage Ⅰ,26 patients (23％) with stage Ⅱ,41 patients (37％) with stage Ⅲ and 35 patients (31％) with stage Ⅳnasopharyngeal carcinoma,respectively.The median age of the cohort was 48 years (range,17-70 years) old.The median dose to the gross tumor volume (GTV) was 60 GyE (range,50-69 GyE).Results With a median follow-up time of 20 months (range,5-45 months),20 patients died and 42 patients developed local recurrence.The 2-year overall survival (OS) and local progression-free survival (LPFS) rates were 85％ and 52％.Both univariate and multivariate analyses demonstrated that stage Ⅳ disease was associated with significantly worse OS.No predictors were found for LPFS.No acute toxicity of grade 3 or higher was observed during reirradiation.Severe (grade 3 or above) late toxicities included xerostomia (n =1),hearing impairment (n =2),temporal lobe injury (n =1) and mucosal necrosis (n =19).Conclusions IMCT is an efficacious and safe treatment for patients with locoregionally recurrent nasopharyngeal carcinoma with acceptable toxicity profile.Long-term follow-up is necessary to further evaluate the long-term efficacy and late toxicities.
ABSTRACT
Objective:To evaluate the short-term tumor control and toxicity of recurrent skull base and cervical spine chordoma and chondrosarcoma in patients treated with pencil beam scanning proton and heavy ion therapy.Methods:Between June 30 th, 2014 and July 30 th, 2018, a total of 45 skull base and cervical spine chordoma ( n=39) and chondrosarcoma ( n=6) patients (28 males and 17 females; mean age at initial presentation of 44 years, range, 14-76 years) were treated in our center for the course of radiotherapy. The median maximum tumor volume was 57 cm 3 (range, 6.6-231.7 cm 3). There were 31 post-operative recurrent patients and 14 post-operative and post-radiated recurrent patients. One patient received proton therapy, 21 patients received combined proton and carbon ion therapy, 23 patients received carbon ion therapy. Results:All patients completed the whole course of the treatment. The median follow-up time was 29 months (range: 8-57 months), the 2-year overall survival (OS), local control (LC), and progression-free survival (PFS) were 82.7%, 85.3%, and 73.8%, respectively. There were no other grade 3-4 acute or late radiation-induced toxicity except one grade 3 acute mucositis. The 2-year OS rates for patients after first-time radiation vs. re-irradiation were 96.2% and 50.3% ( χ2=16.969, P<0.05). Conclusions:The short-term outcomes of pencil beam scanning proton and heavy ion therapy for recurrent skull base and cervical spine chordoma and chondrosarcoma is favorable. Further study is needed for long-term efficacy and safety.
ABSTRACT
Objective:To investigate the safety and efficacy of proton beam radiation therapy (PBRT) in patients with World Health Organization (WHO) GradeⅠ/Ⅱ meningioma.Methods:Twenty-six patients with intracranial ( n=8, 30.8%) or skull-base ( n=18, 69.2%) meningioma treated with PBRT from May 2015 to October 2018 were analyzed retrospectively. The median age of the cohort was 42 years (range 15-79 years). Eight patients had WHO Grade Ⅰ meningioma, and 9 had WHO Grade Ⅱ meningioma, respectively. Nine patients had clinical (radiological) diagnosis without histology. Seven patients received post-surgical PBRT (2 patients underwent Simpson Ⅰ-Ⅲ resection, 5 patients underwent Simpson Ⅳ-Ⅴ resection); 10 patients were irradiated for local recurrence after initial surgical resection. Results:All patients completed planned PBRT without break, and the median dose was 54 Gray-Equivalent (GyE) (range 50.4-60 GyE, 1.8-2 GyE/daily fraction). With a median follow-up of 22.2 (range 1.6-36.4) months, the 2-year overall survival and progression-free survival rates were both 100%. Grade Ⅰ skin erythema and alopecia were observed in 22 patients and Grade Ⅰ mucositis was observed in 2 patients. No acute of late toxicities of Grade 2 or above was observed.Conclusions:PBRT appeared to be a favorable treatment option for intracranial and skull base meningioma. Treatment-induced adverse effects and early response to PBRT were both highly acceptable. Longer follow-up is needed to evaluate the long-term outcome in terms of disease control, survival, as well as potential late effects.
ABSTRACT
Objective:To compare dose distributions between photon versus proton and carbon ion radiotherapy (particle therapy, PT) among patients with gross tumors, and to evaluate the safety and efficacy of PT for thymic malignancies (TM).Methods:From Sept 2015 to Aug 2018, 19 patients with TM who underwent non-palliative PT using pencil beam scanning technique in our hospital and had at least one follow-up were retrospectively analyzed. Diseases staged from Ⅰ-Ⅳ B including 15 Ⅲ-Ⅳ B. All the patients had pathological diagnosis with 10 thymomas, 6 carcinomas and 3 neuroendocrine tumors of the thymus. A set of dosimetric comparisons were conducted in patients with gross tumors at a total dose of 66 GyE, in 33 fractions for photon or proton beams and in 22 fractions for carbon ion beams. Five patients without any local treatment and 7 patients after R2 resection received radical radiotherapy of proton 44.0-48.4 GyE in 20-22 fractions plus carbon ion 21.0-23.1 GyE in 7 fractions, 1 case after complete resection (R0 resection) had proton 45 GyE in 25 fractions, 5 cases after R1 resection had proton 60.0-61.6 GyE in 28-30 fractions and 1 case of recurrence after postoperative radiotherapy had only carbon ion 60 GyE in 20 fractions. Results:The median follow up time was 19.0 (2.4-42.9) months. There were 13 patients with gross tumors, with a median largest diameter of 5.7 (2.7-12.8) cm. The dosimetric study showed that proton and carbon-ion plans significantly reduced the maximum dose to the spinal cord, the mean doses to the organs at risk (OARs) including the lung/heart/esophagus, and the integral dose of the exposed area about 25%-65% compared to photon plans. No other toxicities ≥ grade 3 were observed except one myocardial infarction (grade 4 late toxicity). There was no local failure observed. Metastasis to regional lymph node, lung, pleura, skull base, bone or liver occurred in 4 patients with Ⅲ-Ⅳ B stage disease in 6.1-22.8 months after treatment. The 2-year local control and overall survival rates were 100%, disease free survival and distant metastasis free survival rates were 64.6%. Conclusions:For TMs, PT has significant advantages over photon in terms of sparing OARs, and is safe and effective in patients with TMs after short-time follow-up.
ABSTRACT
Objective@#To investigate the effect of lipiodol as embolization agents in liver, after transcatheter arterial chemoembolization, on dose calculation under the carbon ion treatment plan.@*Methods@#The actual relative linear stopping powers(RLSP)in pure lipiodol, pure gel and lipiodol-gel mixture, together with the correctd RLSPs from their CT images, were compared.In seven typical cases with lipiodol deposition area, carbon ion treatment plan was performed for the original lipiodol images.Successively on the basis of analysis that has made, the RLSP in lipiodol deposition area was corrected to be as in normal liver tissue, for which the carbon ion treatment plan was again performed.A comparison was made of differences in water equivalent depth (WED) and dose distribution on different CT images.@*Results@#The RLSP value corrected according to CT image HU value, lipiodol, and lipiodol-gel mixture may increase by 4.6%-139.0% compared with the measured value. In seven typical cases, deposited lipiodol can cause WED to increase by (0.89±0.41) cm along the field track and RBE by(3.83±1.71)Gy within the 1 cm of distal area of target.@*Conclusions@#In order to improve the accuracy of dose distribution calculation, the HU value and/or RLSP in deposited lipiodol area in liver after transcatheter arterial chemoembolization should being corrected to be as in the normal liver tissue.
ABSTRACT
Objective@#To evaluate the dosimetric difference between carbon ion radiotherapy and photon radiotherapy for treating tumors at lacrimal system.@*Methods@#Using the CT images of 10 patients with tumors at lacrimal system, the carbon ion plan, the photon volume intensity modulation plan (VMAT) and the fixed wild photon intensity modulation radiotherapy (IMRT) plan were generated. The prescription was 54 Gy(RBE) in 18 fractions for clinical target volume (CTV) and 63 Gy(RBE) in 18 fractions for CTV-boost. Dosimetric differences of organ at risks were compared based on the same planning target volumes (PTVs) with similar dose coverages.@*Results@#There was no statistically significant difference in the PTV coverage among three plans (P>0.05). Compared to VMAT and IMRT plans, carbon ion plans reduced the mean doses of eyeballs, mean doses and near-maximum doses of optical nerves of both ipsilateral ( t=7.35, 3.79, 4.66, 8.48, 2.52, 2.76, P<0.05) and contralateral eyes (t=3.87, 10.49, 9.16, 4.43, 6.53, 5.12, P<0.05), while the mean dose of brain was decreased from(5.65±3.58) and (5.76±2.09)Gy(RBE) to (0.81±0.90)Gy(RBE) (t=6.76, 17.33, P<0.05).@*Conclusions@#Compared to photon VMAT or IMRT, carbon ion could reduce the doses to optical critical organs around tumors. Thus, carbon ion radiotherapy has potential to reduce patients′ radiation related side-effects.
ABSTRACT
Objective To observe the short-term effect and toxicities after carbon ion radiotherapy (CIRT) for tracheal adenoid cystic carcinoma (TACC).Methods From March 2016 to October 2017,a total of 10 patients with TACC were treated using CIRT.Among them,three patients had recurrent disease (two after surgery,and one after brachytherapy),one received bronchoscopic cryosurgery for stage Ⅰ disease,and the other 9 had locally advanced disease (3/6 received endoscopic treatment before CIRT).All patients received CIRT using pencil-beam scanning technique.Except that the patient with recurrent disease after brachytherapy received 60 GyE/20 Fx,the patient received cryosurgery and one recurrent patient after surgery received 66 GyE/22 Fx,all other patients received 69 GyE/23 Fx.Results The median follow-up time was 5.5 (1.5-16.4) months.Among the 9 patients with gross tumors,3 patients achieved complete response,2 achieved partial response,and 4 remained stable disease per RECIST 1.1 criteria.The postcryosurgery patient remained no evidence of disease.Except 1 patient experienced grade 4 tracheal stenosis,no other grade ≥ 3 adverse effects were observed.Grade 2 acute toxicities included 1 hoarseness and 1 neutropenia,both relieved after CIRT.Hypothyroidism in one patient was the only observed grade 2 late toxicity.Conclusion CIRT is safe and effective in the management of TACC during a short-time observation.
ABSTRACT
Objective To evaluate the dosimetric difference between carbon ion radiotherapy and photon radiotherapy for treating tumors at lacrimal system. Methods Using the CT images of 10 patients with tumors at lacrimal system, the carbon ion plan, the photon volume intensity modulation plan ( VMAT) and the fixed wild photon intensity modulation radiotherapy ( IMRT) plan were generated. The prescription was 54 Gy(RBE) in 18 fractions for clinical target volume (CTV) and 63 Gy(RBE) in 18 fractions for CTV-boost. Dosimetric differences of organ at risks were compared based on the same planning target volumes ( PTVs) with similar dose coverages. Results There was no statistically significant difference in the PTV coverage among three plans ( P>0. 05) . Compared to VMAT and IMRT plans, carbon ion plans reduced the mean doses of eyeballs, mean doses and near-maximum doses of optical nerves of both ipsilateral ( t=7. 35, 3. 79, 4. 66, 8. 48, 2. 52, 2. 76, P<0. 05 ) and contralateral eyes ( t=3. 87, 10. 49, 9. 16, 4. 43, 6. 53, 5. 12, P<0. 05), while the mean dose of brain was decreased from(5. 65± 3. 58) and ( 5. 76 ± 2. 09 ) Gy ( RBE ) to ( 0. 81 ± 0. 90 ) Gy ( RBE ) ( t= 6. 76, 17. 33, P<0. 05 ) . Conclusions Compared to photon VMAT or IMRT, carbon ion could reduce the doses to optical critical organs around tumors. Thus, carbon ion radiotherapy has potential to reduce patients' radiation related side-effects.
ABSTRACT
Objective@#To verify the safety and efficacy of IONTRIS particle therapy system (IONTRIS) in clinical implementation.@*Methods@#Between 6.2014 and 8.2014, a total of 35 patients were enrolled into this trial: 31 males and 4 females with a median age of 69 yrs (range 39-80). Ten patients had locally recurrent head and neck tumors after surgery, 4 cases with thoracic malignancies, 1 case with hepatocellular carcinoma, 1 case with retroperitoneal sarcoma, and 19 cases with non-metastatic prostate carcinomas. Phantom dose verification was mandatory for each field before the start of radiation.@*Results@#Twenty-two patients received carbon ion and 13 had proton irradiation. With a median follow-up time of 1 year, all patients were alive. Among the 16 patients with head and neck, thoracic, and abdominal/pelvic tumors, 2, 1, 12, and 1 cases developed complete response, partial response, stable disease, or disease progression, respectively. Progression-free survival rate was 93.8% (15/16). Among the 19 patients with prostate cancer, biological-recurrence free survival was 100%. Particle therapy was well tolerated in all 35 patients. Twenty-five patients (71.4%) experienced 33 grade 1 acute adverse effects, which subsided at 1 year follow-up. Six (17.1%) patients developed grade 1 late adverse effects. No significant change in ECOG or body weight was observed.@*Conclusions@#IONTRIS is safe and effective for clinical use. However, long term follow-up is needed to observe the late toxicity and long term result.
ABSTRACT
Objective To evaluate the short-term efficacy and adverse events of pencil beam scanning proton and carbon ion therapy in the treatment of chordoma and chondrosarcoma of the head and neck.Methods Between July 2014 and July 31,2017,61 patients with chordoma and chondrosarcoma of the head and neck receiving proton and heavy ion therapy as the first course of radiotherapy were enrolled.Among them,45 patients were diagnosed with chordoma and 16 cases of chondrosarcoma,39 male and 22 female.The median age was 38 years old (range:14-70 years).The median maximum tumor diameter was 4.1 cm (range:0-8.6 cm).The clivus and the cervical spine were the primary tumor sites.Results Eight patients received proton therapy,21 patients were treated with proton combined with carbon ion therapy and 32 patients received carbon ion therapy.All patients successfully completed the planned radiotherapy.The medial follow-up time was 21 months (range:7-47 months).No grade 3-4 acute toxicity was observed.Only one patient suffered from radiation-induced temporal lobe injury.The 2-year progression-free survival (PFS)and overall survival (OS) were 91％ and 100％.Conclusions Pencil beam scanning proton and heavy ion therapy yields relatively favorable short-term outcomes in the treatment of chordoma and chondrosarcoma of the head and neck.Nevertheless,the long-term clinical efficacy and safety remain to be investigated during follow-up.
ABSTRACT
Objective To evaluate the safety and efficacy of proton and carbon-ion radiotherapy (RT) for stage Ⅰ non-small cell lung cancer (NSCLC) with pencil beam scanning technique.Methods From August 2014 to December 2015,10 patients with stage Ⅰ NSCLC who were inoperable or refused surgery were treated by proton +/-carbon-ion RT.Primary lesions were irradiated using 2-4 portals with 45-degree beams.A total dose of 50-70 GyE/10 fractions,60-64 GyE/15-16 fractions,and 66-72 GyE/22-24 fractions were administered to patients based on tumor location (4 peripheral,3 middle,and 3 central lesions,respectively).Results At the last follow-up in December 2016 with the median follow-up of 18.1 (11.9-28.1) months,local control was found in all patients per CT or PET/CT scanning(6 complete response,3 partial response,and 1 stable disease).However,2 patients with local control (1 partial response and 1 stable disease) experienced a distant failure at 8.7 and 24.9 months after RT,respectively.There was no RT-related Grade 3-5 toxicity in all patients.Grade 2 toxicities were only found in 2 patients (acute skin reaction and leucopenia,respectively).At 1,3-5 months after RT,the pulmonary function tests showed a slightly increase in FVC,FEV1 and DLCO-sb compared with those before RT without statistical significance (P ＞ 0.05).Conclusions The particle RT using pencil beam scanning technique was safe,and yielded encouraging outcome for patients with stage I NSCLC who were inoperable or refused surgery.Further follow-up and prospective clinical studies are warranted in the future.
ABSTRACT
To perform an evaluation of the on-going prospective clinical trials on particle radiation therapy and their impact on the current clinical practice as well as future clinical research and development.Furthermore,to briefly present the results of the registration trial of the IONTRIS particle therapy system at the Shanghai Proton and Heavy Ion Center.We used data from the clinicaltrials,gov and the Particle Therapy Collaborative Organization Group (PTCOG) website.After excluding retrospective and in silico studies,we examined and analyzed the prospective clinical trials for their ion type,targeting disease site,and nature.At the time of this analysis,149 prospective trials were identified on proton and carbon-ion radiation therapy,including 20 were carbon-ion and 129 trials were proton radiation focused,respectively.Except for 15 randomized phase Ⅱ/Ⅲ and Ⅲ trials,134 trials were phase 0-Ⅱ trials.Tumors from nearly all body parts were covered by the on-going trials,but trials on pediatric,GI,lung,prostate,and breast cancer account for the majority.The majority of the currently on-going trials focus on the efficacy and adverse-effects of the new dose/fractionation schemes of particle therapy as well as the use of particle therapy on new indications.Few studies invcstigate the addition of adjuvant therapy or imaging technology used in adjunct with particle therapy.Randomized trials that compare particle radiation therapy versus photon radiation is relatively uncommon.Despite the prevailing use of proton and heavy-ion radiation therapy for cancer treatment,～ 150 prospective clinical trials associated with particle radiation therapy are identified.As the majority of trials aim to investigate more efficacious dose/fractionation and the application of particle therapy on new indications,improved outcome from and expanded utilization of particle radiation therapy can be expected.
ABSTRACT
Objective To study the early response and acute/subacute adverse effects after particle radiation therapy for adenoid cystic carcinoma (ACC) of the head and neck.Methods Between May 2015 and March 2016,a total of 8 patients with ACC of the head and neck were treated using proton and/or carbon-ion radiation therapy.Three patients had early stage and 5 had locally advanced disease.Five patients had an R2 and three achieved an R1 resection.Results Seven patients received intensitymodulated proton therapy (IMPT) followed by intensity-modulated carbon-ion therapy (IMCT) boost.One patient received IMPT only.Among the five patients who had an R2 resection,2/3 patients had partial response (PR)/stable disease (SD) at the end of radiation,0/3 achieved PR/complete response (CR) at 1-month follow-up,and 1/2 achieved PR/CR at 3-months' follow-up after the completion of radiation,respectively.Two patients experienced Grade Ⅲ mucositis during radiation therapy.No patient experienced moderate or severe skin reactions.At the time of this analysis,all patients are alive and no patient had disease progression or recurrence.Conclusions The short-term outcomes indicated that particle therapy is safe and potentially efficacious in the management of head and neck ACC.However,longer follow up is needed to assess late toxicities and long-term efficacy.
ABSTRACT
Deifnitive treatment for locoregionally advanced squamous cell carcinoma of the head and neck region (HNSCC) is challenging, and usually require multidisciplinary efforts involving surgery, radiotherapy, and chemotherapy. Although surgery followed by radiation or chemoradiation therapy remains the standard treatment for resectable disease, combined chemoradiation therapy provides an effective option with organ spearing potential. In addition, combined chemoradiation therapy is the only treatment option for non-metastatic advanced HNSCC. Recently published results from TAX323 and TAX324, two important randomized clinical trials on the efficacy of induction chemotherapy using docetaxel based regimen, showed that induction chemotherapy using TPF can signiifcantly improve patients’ survival as compared to the conventional PF regimen. However, whether TP or TPF induction chemotherapy should be combined with concurrent chemoradiation and considered as part of the standard treatment regimen remains controversial, and requires support from the results of well-designed randomized clinical trial.
ABSTRACT
Objective To evaluate the impact of reducing clinical target volume (CTV) on the efficacy of intensity modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC) . Methods Between August 2003 and March 2007, 380 NPC patients were treated with IMRT with reduced CTV.CTV1, defined as high risk region, included GTV +5 - 10 mm margin and the entire nasopharyngeal mucosa +5 mm submucosal volume; CTV2, designed for potentially involved regions, included the nasopharyngeal cavity (limited to the posterior part of nasal cavity only), maxillary sinus (limited to 5 mm anterior to the posterior nasal aperture and maxillary mucosa), pterygopalatine fossa, posterior ethmoid sinus,parapharyngeal space, skull base, anterior third of clivus and cervical vertebra, inferior spheniod sinus and cavernous sinus and internal group of retropharyngeal lymph nodal regions from the base of skull to cranial edge of the second cervical vertebra. The prescription dose was: GTV 66. 00 -69. 75 Gy/30 - 33 f, CTV1 60. 00 -66. 65 Gy,CTV2/CTVN 54. 0 -55.8 Gy. 308 patients with stage Ⅲ or Ⅳ diseases also received cisplatin-based neoadjuvant chemotherapy. Results The follow-up rate was 100%. 145 patients were followed-up to 3 years. The 3-year estimated local control, regional control, metastasis-free survival,disease-free survival and overall survival rates were 94. 9%, 97.4%, 86. 2%, 80. 9% and 89. 0%,respectively. Multivariate analysis revealed that N-classification was a significant prognostic factor for metastasis-free survival (x2 = 20. 80, P = 0. 001), N-classification (x2 = 18. 30, P = 0. 003) and age (x2 =7. 31, P =0. 004) were independent prognostic factors for overall survival. Grade 2 xerostomia was observed in 5.6% of the patients after two years of IMRT, no Grade 3 or 4 xerostomia was observed. Local, regional,and distant failures were developed in 4. 2%, 2. 6% and 12. 1% of the patients, respectively. Conclusions The IMRT approach with reduced CTV2 provids a favorable outcome for NPC with acceptable toxicities.
ABSTRACT
The prognosis of patients with pancreatic cancer is dismal, especially at the advanced stage of the disease. Surgery is considered as the only curative treatment modality for pancreatic cancer;however, less than 20% of patients are candidates for curative surgical resection. Multidisciplinary management, including radiation therapy with concurrent chemotherapy, followed by systemic chemotherapy, is the treatment of choice for locally advanced pancreatic cancer. An early phase Ⅲ clinical trial conducted by GITSG (GI Tumor Study Group) has demonstrated a survival benefit for concurrent chemoradiation as compared to radiation alone in locally advanced disease. 5-FU,capacitabine and gemcitabine are the most investigated chemotherapy agents used with radiation. Currently thecombined use of gemcitabine and radiation therapy is under active investigation, and may provide substantial clinical advantage over other regimens. Multi-agent chemotherapy regimen used in concurrence with radiation has not demonstrated any significant effect but with severe toxicities. Conformal radiotherapy should be routinely used to treat locally advanced pancreatic cancer with doses of 45-50.4 Gy. The target of locally advanced pancreatic cancer is focussed on the gross tumor with safe margins. The use of IMRT is highly recommended for unresectable tumor, and makes further dose escalation possible.
ABSTRACT
Pancreatic cancer is a highly malignant neoplasm with dismal prognosis. The risk of recurrence and metastasis remains high even for patients who have undergone radical dissection. Therefore, adjuvant therapy after "curative" resection is crucial. However, consensus on the optimal management of pancreatic cancer after surgery has not been reached. Both chemotherapy and concurrent chemoradiation therapy have been advocated. Yet, based upon the results of published phase Ⅲ trials, the consensus and standard strategy of adjuvant treatment after pancreatic cancer surgery is still undo" debate. According to the results of GITSG and RTOG trials, the mainstream in North American is adjuvant chemoradiation. However, based on the results of ESPAC-1 and CONKO-001 studies, the oncologists in Europe usually recommend chemotherapy alone. Furthermore, the superiority of gemcitabine over 5-FU in the adjuvant setting is largely unclear. This article reviewed the main results of the clinical trials in the field of adjuvant treatment of pancreatic cancer.From the authors' view, both the standard dosage of gemcitabine (CONCO-001) and chemoradiation (RTOG-9704) after resection of pancreatic cancer could be considered as candidates for adjuvant strategy. However, the optimal therapy will have to be determined by trials with larger number of patients.
ABSTRACT
The introduction of novel agents targeted to specific molecular targets of cancer cells offers more treatment options and improvement in outcome for exocrine pancreatic adenocarcinoma. Due to the limitations in the scope and scale of researches, this review of clinical studies presents the effects of administering the agents targeting the receptors or ligands of epidermal growth factor (EGF) or vascular endothelial growth factor (VEGF) to treat advanced pancreatic carcinoma. In addition, the basic knowledge on the mechanisms of therapy targeting EGFR and VEGFR were described. Among all agents, erlotinib has been approved by the U.S. Food and Drug Administration and incorporated in a number of treatment guidelines. It has been shown, in a randomized phase Ⅲ clinical trial reported by the National Cancer Institute of Canada, to extend survival when used in combination with gemcitabine;however,its use as monotherapy has not produced significant efficacy. Furthermore, results from a muiticenter randomized clinical trial has demonstrated that the combined utilization of erlotinib and bevaeimlmab, in current with gemcitabine significantly improved the progression-free survival, but has no significant effect on overall survival of patients with advanced pancreatic cancer. Other agents including cetuximab, bevaeizumab, sorafenib, sunitinib, etc. used along or in combination with chemotherapy are under active investigation.