Comparison of skin dose in IMRT and VMAT with TrueBeam and Halcyon linear accelerator for whole breast irradiation.

With the increasing use of flattening filter free (FFF) beams, it is important to evaluate the impact on the skin dose and target coverage of breast cancer treatments. This study aimed to compare skin doses of treatments using FFF and flattening filter (FF) beams for breast cancer. The study established treatment plans for left breast of an anthropomorphic phantom using Halcyon's 6-MV FFF beam and TrueBeam's 6-MV FF beam. Volumetric modulated arc therapy (VMAT) with varying numbers of arcs and intensity modulated radiation therapy (IMRT) were employed, and skin doses were measured at five points using Gafchromic EBT3 film. Each measurement was repeated three times, and averaged to reduce uncertainty. All plans were compared in terms of plan quality to ensure homogeneous target coverage. The study found that when using VMAT with two, four, and six arcs, in-field doses were 19%, 15%, and 6% higher, respectively, when using Halcyon compared to TrueBeam. Additionally, when using two arcs for VMAT, in-field doses were 10% and 15% higher compared to four and six arcs when using Halcyon. Finally, in-field dose from Halcyon using IMRT was about 1% higher than when using TrueBeam. Our research confirmed that when treating breast cancer with FFF beams, skin dose is higher than with traditional FF beams. Moreover, number of arcs used in VMAT treatment with FFF beams affects skin dose to the patient. To maintain a skin dose similar to that of FF beams when using Halcyon, it may be worth considering increasing the number of arcs.

Clinical Application Study of Semi-cylindrical Beam Spoiler for Radiation Treatment of Early-stage Glottic Cancer Patients.

BACKGROUND/AIM: The purpose of this study was to determine whether a semi-cylindrical beam spoiler (sCBS) developed herein effectively increases the skin dose in patients with early-stage glottic cancer. PATIENTS AND METHODS: We measured the surface doses for 26 patients who used the sCBS during treatment of early-stage glottic cancer through a parallel-opposed lateral two-field 6 MV photon beam. Measurements were performed by attaching optically stimulated luminescent dosimeters to the left, right, anterior (in-field), inferior, and superior (out-field) sides of the patient. RESULTS: The measured results were 81.8±2.1% (left), 81.0±1.7% (right), and 76.8±2.7% (anterior) in the in-field region compared to prescription doses, with 5.7±1.7% (superior) and 2.7±0.7% (inferior) in the out-field region. CONCLUSION: sCBS can deliver a suitably ideal surface dose for treatment of early-stage glottic cancer.

Usefulness of Semi-cylindrical Beam Spoiler in Treatment of Early Glottic Cancer Using 6 MV Photon Beam.

BACKGROUND/AIM: To assess the dosimetric influence of a semi-cylindrical beam spoiler (sCBS) for the treatment of early glottic cancer using a 6 MV photon beam. PATIENTS AND METHODS: The 2D dose distributions were also calculated and measured with and without the sCBS and with a 0.5 cm thick bolus. A retrospective study of 8 patients treated between 2012 and 2018 was performed. RESULTS: The 2D dose distributions obtained from the treatment planning system (TPS) and film measurements were in good agreement. In the planning study, the V95%, V100%, conformal index (CI), and homogeneity index (HI) of all pPTVs for the sCBS plans were better than those for the open field plans (p<0.01). Especially, sCBS plans had better skin sparing effect than bolus plans (p<0.05). CONCLUSION: The sCBS of the 6 MV photon beam could be a useful tool for the treatment of early glottic cancers.

Inter-institutional Variation in Intensity-modulated Radiotherapy for Breast Cancer in Korea (KROG 19-01).

BACKGROUND/AIM: To present the variations in the target delineation and the planning results of intensity-modulated radiation therapy (IMRT) for breast cancers. PATIENTS AND METHODS: We requested the target volumes and organs at risk delineation for two cases of left breast cancers, and evaluated the IMRT plans including the supraclavicular and internal mammary node irradiation. RESULTS: Twenty-one institutions participated in this study. Differences in the planning target volume among institutions reached up to three-times for breast-conserving surgery (BCS) case and five-times for mastectomy case. Mean heart doses ranged from 3.3 to 24.1 Gy for BCS case and from 5.0 to 26.5 Gy for mastectomy case. Ipsilateral lung volumes receiving more than 20 Gy ranged from 4.7 to 57.4% for BCS case and from 16.4 to 55.5% for mastectomy case. CONCLUSION: There were large variations in the target delineation and planning results of IMRT for breast cancers among institutions. Considering the increased use of breast IMRT, more standardized protocols are needed.

Hypofractionated intensity-modulated radiotherapy using simultaneous integrated boost technique with concurrent and adjuvant temozolomide for glioblastoma.

AIMS AND BACKGROUND: We assessed the therapeutic efficacy of combined hypofractionated intensity-modulated radiotherapy with temozolomide in patients with primary glioblastoma. METHODS AND STUDY DESIGN: Thirty-nine patients with histologically confirmed glioblastoma were accrued. Using the simultaneous integrated boost technique, a dose of 50 Gy in 5-Gy fractions was applied to the gross tumor volume, together with 40 Gy in 4-Gy fractions and 30 Gy in 3-Gy fractions to the 1- and 2-cm margins from the gross tumor volume, respectively. Patients were also treated with concurrent temozolomide during intensity-modulated radiotherapy, followed by six cycles of adjuvant temozolomide. RESULTS: Median follow-up was 16.8 months (range, 4.3-54.3). Tumor progression was observed in 28 patients (71.8%), and the median time to progression was 6.8 months. Median survival was 16.8 months, and it was affected significantly by the extent of surgery. During adjuvant temozolomide treatment, 3 patients (9.7%) developed grade 3-4 hematologic or hepatic toxicity. Radiation necrosis developed in 7 patients (17.9%) and massive necrosis, requiring emergency surgery, in 1 patient (2.6%). CONCLUSIONS: The regimen of hypofractionated intensity-modulated radiotherapy with temozolomide showed a relatively good outcome in patients with glioblastoma. Further studies are required to define the optimal fraction size for glioblastoma using this highly sophisticated radiation technique.

Long-term outcomes of concomitant chemoradiotherapy incorporating high-dose-rate brachytherapy to treat locally advanced cervical cancer.

AIM AND BACKGROUND: We reviewed the long-term clinical outcomes of patients treated with cisplatin-based concurrent chemoradiotherapy (CCRT) incorporating high-dose-rate (HDR) intracavitary brachytherapy (ICBT) in terms of toxicity, local control and survival rates. In addition, we identified prognostic factors for overall and disease-free survival. METHODS AND STUDY DESIGN: . Two hundred and nine patients with stage IB2-IVA cervical cancer underwent curative cisplatin-based CCRT plus HDR ICBT. Women with stage IB2-IIB disease were given 41.4 Gy of external radiotherapy followed by 35 Gy (in 7 fractions) of ICBT. Women with stage IIIA-IVA were given 50.4 Gy followed by 30 Gy (in 6 fractions) of ICBT. Patients with parametrial disease or pelvic lymphadenopathy were given parametrial boosts via external beam radiation at a dose of up to 65 Gy to thickened and 60 Gy to unthickened parametrial regions. RESULTS: One hundred and thirty (62%) patients experienced acute grade 3-4 hematological toxicities and 11 (5%) patients had late grade 3 gastrointestinal or genitourinary complications. Complete responses occurred in 168 (80%) women as determined by clinical and imaging studies. The median follow-up period was 52 months for surviving patients and the 5-year overall and disease-free survival rates were 74% and 67%, respectively. Multivariate analysis indicated that tumor size and paraaortic lymph node involvement were prognostically significant in terms of overall survival, and that tumor diameter was a significant prognostic factor and pelvic lymph node status a marginally significant prognostic factor for disease-free survival. CONCLUSIONS: Patients treated with our current HDR ICBT protocol have acceptably low late complication rates and local control and survival rates comparable to those reported in other studies. Tumor diameter was an important prognostic factor in terms of both overall and disease-free survival, emphasizing the need for modern ICBT methodologies.

Preparation and characterization of nanosized gold catalysts supported on Co3O4 and their activities for CO oxidation.

Gold catalysts supported on Co3O4 were prepared by co-precipitation (CP), deposition-precipitation (DP), and impregnation (IMP) methods. The Au/Co3O4 catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and temperature programmed reduction (TPR) to understand the different activities for CO oxidation with different preparation methods. Gold particles below 5 nm supported on Co3O4 by DP method were found to be more exposed to the surface than those by CP and IMP methods, and this catalyst was highly active and stable in CO oxidation. Finally, catalytic activity of Au/Co3O4 catalyst for CO oxidation was strongly dependent on the gold particle size.

Treatment outcome of postoperative radiotherapy for retroperitoneal sarcoma.

PURPOSE: To evaluate the treatment outcome and prognostic factor after postoperative radiotherapy in retroperitoneal sarcoma. MATERIALS AND METHODS: Forty patients were treated with surgical resection and postoperative radiotherapy for retroperitoneal sarcoma from August 1990 to August 2008. Treatment volume was judged by the location of initial tumor and surgical field, and 45-50 Gy of radiation was basically delivered and additional dose was considered to the high-risk area. RESULTS: The median follow-up period was 41.4 months (range, 3.9 to 140.6 months). The 5-year overall survival (OS) was 51.8% and disease free survival was 31.5%. The 5-year locoregional recurrence free survival was 61.9% and distant metastasis free survival was 50.6%. In univariate analysis, histologic type (p = 0.006) was the strongest prognostic factor for the OS and histologic grade (p = 0.044) or resection margin (p = 0.032) had also effect on the OS. Histologic type (p = 0.004) was unique significant prognostic factor for the actuarial local control. CONCLUSION: Retroperitoneal sarcoma still remains as a poor prognostic disease despite the combined modality treatment including surgery and postoperative radiotherapy. Selective dose-escalation of radiotherapy or combination of effective chemotherapeutic agent must be considered to improve the treatment result especially for the histopathologic type showing poor prognosis.

Feasibility and outcome of concurrent chemoradiotherapy for recurrent cervical carcinoma after initial surgery.

AIMS AND BACKGROUND: The prognosis for recurrent cervical carcinoma following initial surgery is dismal even when aggressive radiotherapy or salvage surgery is used. We retrospectively reviewed hospital records to evaluate the efficacy and feasibility of concurrent chemoradiotherapy as a salvage treatment. METHODS: From 1999 to 2007, 47 patients received salvage chemoradiotherapy. Involved-field irradiation was delivered at a median dose of 64.8 Gy (range, 36-100.2), including brachytherapy boost in 10 patients. Pelvic re-irradiation was performed in 4 of the 12 women who had a previous history of pelvic radiotherapy. All but one patient received cisplatin-based concomitant chemotherapy during radiotherapy. RESULTS: The median overall follow-up period was 27 months and for surviving patients was 57 months. The interval between initial surgery and recurrence was 22 months (range, 4-203), and the median recurrent mass size was 4 cm (range, 0.5-11). In 34 patients, recurrent tumors were confined to the pelvis (21 central and 13 peripheral). Grade 3-4 acute hematologic toxicity was the most frequent toxicity and was observed in 29 (62%) women. Five-year actuarial cumulative incidence of severe gastrointestinal and genitourinary toxicity was 13% and 7%, respectively. Thirty-three patients (70%) showed a complete response and 9 (19%) a partial response following salvage chemoradiation. Five-year overall and disease-free survival rates were 44% and 41%, respectively. CONCLUSIONS: Salvage chemoradiotherapy appears to be a feasible treatment option for women with recurrent cervical carcinoma following surgery. The treatment had a high salvage rate and acceptable late complication rate, despite being associated with substantial acute toxicity.

Concurrent chemoradiotherapy or radiotherapy alone for locally advanced cervical cancer in elderly women.

AIMS AND BACKGROUND: To evaluate the efficacy and toxicity of concurrent chemoradiotherapy or radiotherapy alone in elderly patients with locally advanced cervical carcinoma (stage IB2-IVA). METHODS AND STUDY DESIGN: We retrospectively reviewed the medical records of 105 women aged 265 years who received radiotherapy (group I, n=61) or concurrent chemoradiotherapy (group II, n=44). Patients received a median dose of 76.4 Gy to point A, including 30-35 Gy of high-dose intracavity brachytherapy. The concurrent chemoradiotherapy group received platinum-based chemotherapy. RESULTS: The median follow-up was 65 months for surviving patients. There was no significant difference in compliance to radiotherapy between the two groups. Most acute toxicities were hematologic; acute hematologic and gastrointestinal toxicity were significantly more common in group II. Five-year overall survival and cancer-specific survival rates were, respectively, 53.5% and 66.6% in group I and 61.8% and 68.8% in group II. Performance status, comorbidity index, tumor size, and stage were independent prognostic factors for overall survival, whereas stage was the only prognostic factor for cancer-specific survival. CONCLUSIONS: The analysis showed no benefit of concurrent chemoradiotherapy with respect to overall survival and cancer-specific survival in elderly women. A prospective study is needed to determine the role of concurrent chemoradiotherapy in this population.

Clinical significance of NQO1 C609T polymorphisms after postoperative radiation therapy in completely resected non-small cell lung cancer.

PURPOSE: To investigate the clinical significance of NQO1 C609T polymorphisms to treatment outcome after postoperative radiation therapy in completely resected non-small cell lung cancer (NSCLC). METHODS: One hundred and sixteen, Korean-ethnic, patients who were treated with surgery and postoperative radiation therapy from February 2000 to September 2005 in Asan Medical Center (Seoul, South Korea) were analyzed. All patients received 5040cGy radiation to surgical stump, mediastinum and ipsilateral supraclavicular node. NQO1 C609T polymorphisms were examined from a peripheral blood sample in all patients. Three types of NQO1 C609T polymorphisms were designated as C/C, C/T and T/T. Chest computed tomography was routinely checked after radiation therapy at every 3 or 6 months and locoregional tumor control, distant metastasis and survival by NQO1 C609T genotype were analyzed. RESULTS: The proportion of NQO1 C609T polymorphisms was 27.6% for C/C, 53.4% for C/T and 19.0% for T/T. Most patients were men and had squamous cell carcinoma or adenocarcinoma. Median age of patients was 61 years. Major failure pattern was distant metastasis and 13 (11.2%) patients showed locoregional recurrence within the field of previous radiation therapy. Crude locoregional recurrence rate was significantly different by NQO1 genotype; 6.3% in C/C, 8.1% in C/T, and 27.3% in T/T (p=0.03), but distant metastasis was not different. Median follow-up time was 49.2 months (range: 3.4-103.5 months). Locoregional recurrence-free survival (LRRFS) was affected in T/T genotype compared with C/C or C/T genotype (p=0.01, Kaplan-Meier method), but distant metastasis-free survival (DMFS) or overall survival (OS) was not different by NQO1 genotype in univariate analysis. NQO1 genotype was also a significant factor for LRRFS (p=0.01) in multivariate analysis. Radiation-induced pneumonitis or esophagitis was tolerable in all patients and the difference by NQO1 genotype was not observed. CONCLUSIONS: NQO1 C609T polymorphisms could be a predictive factor for the locoregional tumor control after postoperative radiation therapy in completely resected NSCLC.

High-dose extended-field irradiation and high-dose-rate brachytherapy with concurrent chemotherapy for cervical cancer with positive para-aortic lymph nodes.

PURPOSE: To determine the efficacy and toxicity of extended-field radiotherapy (RT) with concurrent platinum-based chemotherapy in patients with uterine cervical carcinoma and positive para-aortic nodes. METHODS AND MATERIALS: We retrospectively reviewed the results for 33 women with Stage IB-IVB cervical cancer. Each patient had received 59.4 Gy, including a three-dimensional conformal boost to the para-aortic lymph nodes and 41.4-50.4 Gy of external beam radiotherapy to the pelvis. Each patient also underwent six or seven applications of high-dose-rate brachytherapy (median, 5 Gy to point A at each session). RESULTS: The median follow-up period of surviving patients was 39 months. The most common acute toxicity was hematologic, observed in 23 women. Severe acute and late gastrointestinal toxicity was observed in 3 and 4 patients, respectively. More than three-quarters of patients showed a complete response, encompassing the primary mass, metastatic pelvic, and para-aortic lymph nodes. Of the 33 women, 15 had no evidence of disease, 6 had persistent disease, 4 developed in-field failures, and 6 developed distant failures. The 5-year overall and disease-free survival rate was 47% and 42%, respectively. CONCLUSION: Concurrent chemoradiotherapy with extended-field radiotherapy is feasible in women with uterine cervical carcinoma and positive para-aortic lymph nodes, with acceptable late morbidity and a high survival rate, although it was accompanied by substantial acute toxicity.

Fractionated stereotactic body radiation therapy for medically inoperable stage I lung cancer adjacent to central large bronchus.

PURPOSE: To assess the body-framed stereotactic body radiation therapy (SBRT) results and toxicity for medically inoperable stage I lung cancer adjacent to central large bronchus and then compare the results with those of SBRT in peripheral lung tumor in the aspects of survival and SBRT-related pulmonary toxicities. MATERIALS: From June 1999 to May 2006, 32 patients diagnosed as stage I, T1N0 or T2N0, resectable NSCLC were treated with body-frame based fractionated SBRT. Thirty-one patients had several medical problems conflicting surgical procedure. Stereotactic body frame was used for improving setup accuracy. Doses of 10-20 Gy per fraction were delivered to the planning target volume (PTV) up to a total dose of 40-60 Gy with three to four fractions on consecutive days. Centrally located tumor was defined as the tumor within 2 cm apart from large bronchial tree, and was subdivided into bronchial (main/lobar bronchus) and peribronchial (segmental or distal). RESULTS: Median follow-up was 26.5 months. The 6-month major response rate, including complete or partial response, was 53.1%. One patient showed progressive disease 1 month after SBRT. The 1- and 2-year actuarial local tumor control rates were both 85.3%. Overall survival was 70.9% at 1 year and 38.5% at 2 years, and survival was not correlated with SBRT dose. Of 9 patients with centrally located tumors, three (33%) experienced Grades 3-5 pulmonary toxicities. Eight patients showed partial or complete bronchial stricture and secondary loss of normal lung volume. Median time to bronchial stricture was 20.5 months. Overall survival did not differ by tumor location. CONCLUSIONS: SBRT in this fractionation should not be given to central lung tumors because it can cause the late major airway toxicities in some patients. More protracted hypofractionated treatment regimen may be more safe than that used usually in SBRT for central lung tumors.

Prospective randomized comparison of monthly fluorouracil and cisplatin versus weekly cisplatin concurrent with pelvic radiotherapy and high-dose rate brachytherapy for locally advanced cervical cancer.

OBJECTIVE: To compare monthly fluorouracil (FU) plus cisplatin and weekly cisplatin concurrent with radiotherapy for locally advanced cervical cancer. METHODS: A total of 158 patients (stages IIB through IVA) without para-aortic lymph nodes were randomized to receive 3 monthly cycles of FU (1000 mg/m2/day i.v.) plus cisplatin (20 mg/m2/day i.v.) for 5 days (group I, n=79) or 6 cycles of weekly cisplatin (30 mg/m2 i.v.) (group II, n=79), concurrent with definitive radiotherapy. Radiotherapy consisted of external irradiation to the whole pelvis of 41.4-50.4 Gy in 23-28 fractions plus high-dose rate (HDR) intracavitary brachytherapy (30-35 Gy in 6-7 fractions) to point A, together with a parametrial boost. Compliance with treatment, toxicity, response, and survival was analyzed and compared. RESULTS: Of the 158 women, 155 women were eligible for analysis; the median follow-up of surviving patients was 39 months. Full planned chemoradiotherapy was delivered to 47 (60%) and 55 (71%) patients in groups I and II, respectively. The incidence of acute grade 3/4 hematologic toxicity was 43% and 26% (p=0.037). The complete response rate of each group was 91%. Four-year overall and progression-free survival rates were 70% and 67%, respectively, in group I and 67% and 66%, respectively, in group II. CONCLUSIONS: The regimen of chemoradiation using weekly cisplatin significantly improves compliance with treatment and reduces acute hematologic toxicity, while not affecting response and survival rates.

Guiding curve based on the normal breathing as monitored by thermocouple for regular breathing.

Adapting radiation fields to a moving target requires information continuously on the location of internal target by detecting it directly or indirectly. The aim of this study is to make the breathing regular effectively with minimizing stress to the patient. A system for regulating patient's breath consists of a respiratory monitoring mask (ReMM), a thermocouple module, a screen, inner earphones, and a personal computer. A ReMM with thermocouple was developed previously to measure the patient's respiration. A software was written in LabView 7.0 (National Instruments, TX), which acquires respiration signal and displays its pattern. Two curves are displayed on the screen: One is a curve indicating the patient's current breathing pattern; the other is a guiding curve, which is iterated with one period of the patient's normal breathing curve. The guiding curves were acquired for each volunteer before they breathed with guidance. Ten volunteers participated in this study to evaluate this system. A cycle of the representative guiding curve was acquired by monitoring each volunteer's free breathing with ReMM and was then generated iteratively. The regularity was compared between a free breath curve and a guided breath curve by measuring standard deviations of amplitudes and periods of two groups of breathing. When the breathing was guided, the standard deviation of amplitudes and periods on average were reduced from 0.0029 to 0.00139 (arbitrary units) and from 0.359 s to 0.202 s, respectively. And the correlation coefficients between breathing curves and guiding curves were greater than 0.99 for all volunteers. The regularity was improved statistically when the guiding curve was used.

Differences in abdominal organ movement between supine and prone positions measured using four-dimensional computed tomography.

BACKGROUND AND PURPOSE: To analyze the differences in intrafractional organ movement throughout the breathing cycles between the supine and prone positions using four-dimensional computed tomography (4D CT). MATERIALS AND METHODS: We performed 4D CT on nine volunteers in the supine and prone positions, with each examinee asked to breathe normally during scanning. The movement of abdominal organs in the cranio-caudal (CC), anterior-posterior (AP) and right-left (RL) directions was quantified by contouring on each phase between inspiration and expiration. RESULTS: The mean intrafractional motions of the hepatic dome, lower tip, pancreatic head and tail, both kidneys, spleen, and celiac axis in the supine/prone position were 17.3/13.0, 14.4/11.0, 12.8/8.9, 13.0/10.0, 14.3/12.1, 12.3/12.6, 11.7/12.6 and 2.2/1.8mm, respectively. Intrafractional movements of the liver dome and pancreatic head were reduced significantly in the prone position. The CC directional excursions were major determinants of the 3D displacements of the abdominal organs. Alteration from the supine to the prone position did not change the amount of intrafractional movements of kidneys, spleen, and celiac axis. CONCLUSION: There was a significant reduction in the movements of the liver and pancreas during the prone position, especially in the CC direction, suggesting possible advantage of radiotherapy to these organs in this position.

The Feasibility of 18F-FDG PET scans 1 month after completing radiotherapy of squamous cell carcinoma of the head and neck.

UNLABELLED: Our purpose was to prospectively evaluate the efficacy of PET with (18)F-FDG 1 mo after the completion of radiotherapy in patients with squamous cell carcinoma of the head and neck (SCCHN). METHODS: Ninety-seven patients underwent (18)F-FDG PET scans before and after radiotherapy for nondisseminated SCCHN. The first scans were obtained no more than 4 wk before the start of radiotherapy, and follow-up scans were obtained 1 mo after the completion of radiotherapy. (18)F-FDG PET images were analyzed using standardized uptake values (SUVs). All patients were followed for at least 6 mo or until death. RESULTS: The median SUVs of preradiotherapy primary sites and nodes were 6.5 (range, 2.3-23.0) and 5.6 (range, 1.2-16.8), respectively. The median SUVs of postradiotherapy primary sites and nodes were 1.8 (range, basal status value to 9.7) and 1.8 (range, basal status value to 8.6), respectively. Evaluation of the postradiotherapy status of tumors in these SCCHN patients showed the sensitivity of (18)F-FDG PET to be 88%, the specificity to be 95%, and the overall diagnostic accuracy to be 94.9%. CONCLUSION: Our results indicate that (18)F-FDG PET might be a valuable imaging method for evaluating the response to radiotherapy in patients with SCCHN. One month after the completion of radiotherapy is not too early for follow-up (18)F-FDG PET to be performed to evaluate the response to radiotherapy.

Optimal time interval between capecitabine intake and radiotherapy in preoperative chemoradiation for locally advanced rectal cancer.

PURPOSE: Capecitabine and its metabolites reach peak plasma concentrations 1 to 2 hours after a single oral administration, and concentrations rapidly decrease thereafter. We performed a retrospective analysis to find the optimal time interval between capecitabine administration and radiotherapy for rectal cancer. METHODS AND MATERIALS: The time interval between capecitabine intake and radiotherapy was measured in patients who were treated with preoperative radiotherapy and concurrent capecitabine for rectal cancer. Patients were classified into the following groups. Group A1 included patients who took capecitabine 1 hour before radiotherapy, and Group B1 included all other patients. Group B1 was then subdivided into Group A2 (patients who took capecitabine 2 hours before radiotherapy) and Group B2. Group B2 was further divided into Group A3 and Group B3 with the same method. Total mesorectal excision was performed 6 weeks after completion of chemoradiation and the pathologic response was evaluated. RESULTS: A total of 200 patients were enrolled in this study. Pathologic examination showed that Group A1 had higher rates of complete regression of primary tumors in the rectum (23.5% vs. 9.6%, p = 0.01), good response (44.7% vs. 25.2%, p = 0.006), and lower T stages (p = 0.021) compared with Group B1; however, Groups A2 and A3 did not show any improvement compared with Groups B2 and B3. Multivariate analysis showed that increases in primary tumors in the rectum and good response were only significant when capecitabine was administered 1 hour before radiotherapy. CONCLUSION: In preoperative chemoradiotherapy for rectal cancer, the pathologic response could be improved by administering capecitabine 1 hour before radiotherapy.

Clinical results of stereotactic body frame based fractionated radiation therapy for primary or metastatic thoracic tumors.

The aim of this study was to evaluate the treatment outcomes of stereotactic body radiation therapy for treating primary or metastatic thoracic tumors using a stereotactic body frame. Between January 1998 and February 2004, 101 lesions from 91 patients with thoracic tumors were prospectively reviewed. A dose of 10-12 Gy per fraction was given three to four times over consecutive days to a total dose of 30-48 Gy (median 40 Gy). The overall response rate was 82%, with 20 (22%) complete responses and 55 (60%) partial responses. The one- and two-year local progression free survival rates were 90% and 81%, respectively. The patients who received 48 Gy showed a better local tumor control than those who received less than 48 Gy (Fisher exact test; p = 0.004). No pulmonary complications greater than a RTOG toxicity criteria grade 2 were observed. The experience of stereotactic body frame based radiation therapy appears to be a safe and promising treatment modality for the local management of primary or metastatic lung tumors. The optimal total dose, fractionation schedule and treatment volume need to be determined after a further follow-up of these results.