Feasibility of fast, four-dimensional computed tomography-based O-ring LINAC plans for lung stereotactic body radiotherapy in patients with poor performance status.

Purpose: We aimed to retrospectively analyzed the feasibility of fast four-dimensional computed tomography (4DCT)-based O-ring LINAC treatment for patients with an average respiratory amplitude was< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-stereotactic body radiotherapy (SBRT). Methods: This study included data of 38 patients who received lung 4D-SBRT and had average respiratory amplitude< 0.5 cm in the full phase. C-arm LINAC plans were based on 4DCT data obtained at phase values ranging from 20-70% using a C-arm LINAC. O-ring LINAC plans were retrospectively established based on 4DCT data obtained at phase values of 0-90% using an O-ring LINAC. The conformity index (CI), homogeneity index (HI), and gradient measurement of the planning target volumes (PTV) were analyzed to compare dosimetric data between C-arm LINAC and O-ring LINAC plans. Organs at risk were analyzed in accordance with the Radiation Therapy Oncology Group 0915 protocol. Treatment delivery time and total monitor units were analyzed to compare the efficiency of treatment delivery. Statistical comparisons were performed using the Wilcoxon signed-rank test (P< 0.05). Results: For the PTV, there was no significant difference in the CI or HI between C-arm LINAC and O-ring LINAC plans. For organs-at-risk, all plans met the criteria for dose constraint. There was a significant difference between C-arm LINAC and O-ring LINAC plans except in the spinal cord. Treatment delivery time was 92% longer for C-arm LINAC plans than for O-ring LINAC plans. The total MU value for C-arm LINAC plans was 9.6% higher than that for O-ring LINAC plans. Conclusion: We verified the feasibility of fast 4DCT-based O-ring LINAC treatment for patients with average respiratory amplitude< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-SBRT.

Dosimetric comparison of VitalBeam® and HalcyonTM 2.0 for hypofractionated VMAT with simultaneous integrated boost treatment of early-stage left-sided breast cancer.

PURPOSE: This study compared the quality of treatment plans for early-stage, left-sided breast cancer, as planned for and delivered by the HalcyonTM and VitalBeam® . MATERIALS AND METHODS: Fifteen patients diagnosed with early-stage left-sided breast cancer, who had received VMAT with hypofractionated SIB, were recruited. All cases were planned using HalcyonTM comprising a dual-layer MLC (DL-MLC) and VitalBeam® with a Millennium 120 MLC (VB-MLC). For the PTVs, the quality of coverage (QC), conformity index (CI), and homogeneity index (HI) were calculated for each plan. The dosimetric differences between the two treatment plans were statistically compared using the Wilcoxon signed-rank test (p < 0.05). To evaluate delivery efficiency, the average delivery time for each patient's treatment plan was recorded and compared. RESULTS: For the PTVs, the two plans (DL-MLC and VB-MLC) were comparable in terms of the QC, CI, and HI. However, V30Gy and Dmean for the heart in the DL-MLC plan were significantly reduced by 0.49% and 14.6%, respectively, compared with those in the VB-MLC plan (p < 0.05). The Dmean value for the ipsilateral lung in the DL-MLC plan significantly decreased by 5.5%, compared with that in the VB-MLC plan (p < 0.05). In addition, the delivery times for the DL-MLC and VB-MLC plans were 79 ± 10 and 101 ± 11 s, respectively. CONCLUSIONS: DL-MLC plans were found to improve OAR sparing. In particular, when treating left-sided breast cancer via DL-MLC plans, the risk of heart toxicity is expected to be reduced.

Ropivacaine continuous wound infusion after mastectomy with immediate autologous breast reconstruction: A retrospective observational study.

ABSTRACT: Continuous wound infusion usually provides postoperative analgesia as a multimodal analgesia with systemic opioid use. When continuous wound infusion of local anesthetics (LA) supports successful postoperative analgesia without systemic opioid use, the side effects of opioid can be reduced. Nevertheless, continuous wound infusion after mastectomy with immediate autologous breast reconstruction leads to concerns about wound healing. This study evaluated analgesic effects and wound healing conditions of continuous wound infusion of LA compared with opioid-based, intravenous patient-controlled analgesia (IV PCA) in mastectomy with immediate autologous breast reconstruction.This retrospective observational study included females, aged between 33 and 67 years, who underwent mastectomy with immediate autologous breast reconstruction. Sixty-five patients were enrolled. The eligible patients were placed into 2 groups for managing postoperative pain, one used continuous wound infusion with 0.5% ropivacaine (ON-Q, n = 32) and the other used a fentanyl-based IV PCA (IV PCA, n = 33). Using the electronic medical record system, the postoperative recovery profiles were examined over 5 days using a visual analogue scale (VAS), incidence of postoperative nausea and vomiting (PONV), incidence of sleep disturbance, frequency of rescue analgesic use, analgesia-related adverse events, length of hospital stay, and degree of patient satisfaction. The condition of the surgical wound was observed for 1 year after surgery.The primary endpoint was the intensity of pain at 6 hours after surgery. The VAS was comparable between the groups (P > .05). Although recovery profiles and the degree of patient satisfaction were similar between the groups, the incidence of PONV was significantly lower in the ON-Q group than in the IV PCA group on the day of surgery and postoperative day 1. No patients had severe wound complications. The satisfaction score of analgesia in the ON-Q group was comparable with that of the patients in the IV PCA group.This study demonstrates that single use of continuous wound infusion showed comparable analgesia with fentanyl-based IV PCA in patients who underwent mastectomy with immediate autologous breast reconstruction. Furthermore, the continuous infusion of LA directly on the surgical site did not significantly affect wound healing.

Comparing efficacy of high-dose rate brachytherapy versus helical tomotherapy in the treatment of cervical cancer.

OBJECTIVE: Boost radiation using brachytherapy (BT) is a standard treatment for local disease control in concomitant chemoradiation therapy (CCRT) for advanced cervical cancer. However, it is associated with gastrointestinal and genitourinary complications. Hence, this study investigates the feasibility of helical tomotherapy (HT) as an alternative to BT. METHODS: Medical records of patients who underwent CCRT between 2000 and 2017 at a single institution were retrospectively reviewed. Patients with stage IIB-IVA cancers were selected based on the 2009 criteria of The International Federation of Gynaecology and Obstetrics. External beam radiation combined with chemotherapy was followed by either BT or HT. The propensity score matching of both groups was calculated using logistic regression analysis. Disease outcomes and treatment-related adverse events were compared between the 2 groups. RESULTS: The matched population included 70 BT patients and 35 HT patients. The 5-year progression-free survival rates for BT and HT were 72.6% and 72.5%, respectively (p=0.721). There was no difference in the overall survival rate between the two groups (p=0.203). The presence of acute and chronic gastrointestinal complications was also similar between the groups (p=0.460 and p=0.563, respectively). The chronic genitourinary toxicities were also comparable (p=0.105). CONCLUSIONS: HT boost treatment showed comparable disease outcomes with those observed with conventional BT in patients with advanced cervical cancer. HT could be a complementary boost protocol as a single modality or hybrid with BT in selected patients. Further studies with longer follow-up periods are warranted to confirm long-term outcomes.

Sequential simulation computed tomography allows assessment of internal rectal movements during preoperative chemoradiotherapy in rectal cancer.

PURPOSES: The purpose of this study was to assess the internal rectal movement and to determine the factors related to extensive internal rectal movement using sequential simulation computed tomography (CT) images. MATERIALS AND METHODS: From 2010 to 2015, 96 patients receiving long-course preoperative chemoradiotherapy were included in our retrospective study. The initial simulation CT (Isim-CT) and follow-up simulation CT (Fsim-CT) for a boost were registered according to the isocenters and bony structure. The rectums on Isim-CT and Fsim-CT were compared on four different axial planes as follows: (1) lower pubis symphysis (AXVERYLOW), (2) upper pubis symphysis (AXLOW), (3) superior rectum (AXHIGH), and (4) middle of AXLOW and AXHIGH (AXMID). The involved rectum in the planning target volume was evaluated. The maximal radial distances (MRD), the necessary radius from the end of Isim-CT rectum to cover entire Fsim-CT rectum, and the common area rate (CAR) of the rectum (CAR, (Isim-CT∩Fsim-CT)/(Isim-CT)) were measured. Linear regression tests for the MRDs and logistic regression tests for the CARs were conducted. RESULTS: The mean ± standard deviation (mm) of MRDs and CAR <80% for AXVERYLOW, AXLOW, AXMID, and AXHIGH were 2.3 ± 2.5 and 8.9%, 3.0 ± 3.7 and 17.4%, 4.0 ± 5.2 and 27.1%, and 4.1 ± 5.2 and 25%, respectively. For MRDs and CARs, a higher axial level (AXVERYLOW/AXMID-HIGH, P = 0.018 and P = 0.034, respectively), larger bladder volume (P = 0.054 and P = 0.017, respectively), smaller bowel gas extent (small/marked, P = 0.014 and P = 0.001, respectively), and increased bowel gas change (decrease/increase, both P < 0.001) in rectum were associated with extensive internal rectal movement in multivariate analyses. CONCLUSIONS: As a result of following internal rectal movement through sequential simulation CT, the rectum above the pubis symphysis needs a larger margin, and bladder volume and bowel gas should be closely observed.

Factors predicting intolerance to definitive conventional radiotherapy in geriatric patients.

PURPOSE: Although radiotherapy can be administered with a relatively low therapeutic burden, many elderly patients do not complete radiotherapy. In order to predict intolerance during radiotherapy, this study retrospectively analyzed the frequency of and risk factors for radiotherapy interruption among geriatric patients. METHODS: From September 2009 to December 2016, 353 patients aged ≥70 years received definitive radiotherapy with a conventionally fractionated schedule. "Total interruption" included completion of ≤90% of a planned radiotherapy, temporary discontinuation, and treatment-related mortality within 2 months. "Early-phase incompletion" and "mid-phase incompletion" represented completion of ≤50 and ≤80% of a planned radiotherapy, respectively. RESULTS: The median age of patients was 74 years. Early- and mid-phase incompletions and total interruption occurred in 4.2, 9.3, and 19.3% of patients, respectively. Total interruption occurred frequently in cancers involving the thorax (27.4%), head and neck (23.1%), abdomen (20.0%), pelvis (17.4%), and breast/extremity (8.1%). The Eastern Cooperative Oncology Group (ECOG) performance score (P = 0.004 and 0.002), serum albumin level (P = 0.016 and 0.002), and the expected 5­year survival (P = 0.033 and 0.034) were significant factors for mid-phase incompletion and total interruption. Age ≥ 75 years (P = 0.008), concurrent chemotherapy (P = 0.017), and the extent of radiation field (P = 0.027) were factors associated with total interruption. CONCLUSION: Overall, 19.3% of the elderly patients showed treatment intolerance during conventional radiotherapy. Serum albumin level and ECOG performance score should be considered as surrogate markers for radiotherapy interruption prior to the decision regarding definite conventional radiotherapy.

Validation of Nomograms for Survival and Metastases after Hysterectomy and Adjuvant Therapy in Uterine Cervical Cancer with Risk Factors.

Background. Three nomogram models for early stage uterine cervical cancer have been developed (KROG 13-03 for overall survival [OS], SNUH/AMC for disease-free survival [DFS], and KROG 12-08 for distant metastases-free survival [DMFS]) after radical hysterectomy (RH) and pelvic lymph node dissection (PLND). This study aimed to validate these models using our cohort with adjuvant radiotherapy. Methods. According to the eligibility criteria of nomogram studies, patients were enrolled in Group A (N = 109) for the two KROG models (RH with PLND and whole pelvic irradiation) and Group B (N = 101) for the SNUH/AMC model (RH with PLND and squamous histology). Using Cox-regression hazard models, the prognostic factors of our cohorts were evaluated. The risk probabilities induced from published nomogram scores were calculated and the concordance indices were evaluated. Results. Group A had 88.1% 5-year OS and 86.0% 5-year DMFS. Group B had 83.0% 5-year DFS. In multivariate analyses, large tumor size for OS (HR 8.62, P < 0.001) and DMFS (HR 5.13, P = 0.003), young age (≤40 versus 41-64 years) for OS (HR 4.63, P = 0.097) and DFS (HR 3.44, P = 0.051), and multiple lymph node metastases (0 versus ≥3) for DMFS (HR 4.03, P = 0.031) and DFS (HR 3.90, P = 0.038) were significantly correlated. The concordance indices for OS, DMFS, and DFS were 0.612 (P = 0.002), 0.597 (P = 0.014), and 0.587 (P = 0.020), respectively. Conclusion. The developed nomogram models after RH and PLND are clinically useful in predicting various types of survival with significance.

Comprehensive Evaluation of Personal, Clinical, and Radiation Dosimetric Parameters for Acute Skin Reaction during Whole Breast Radiotherapy.

Skin reaction is major problem during whole breast radiotherapy. To identify factors related to skin reactions during whole breast radiotherapy, various personal, clinical, and radiation dosimetric parameters were evaluated. From January 2012 to December 2013, a total of 125 patients who underwent breast conserving surgery and adjuvant whole breast irradiation were retrospectively reviewed. All patients had both whole breast irradiation and boost to the tumour bed. Skin reaction was measured on the first day of boost therapy based on photography of the radiation field and medical records. For each area of axilla and inferior fold, the intensity score of erythema (score 1 to 5) and extent (score 0 to 1) were summed. The relationship of various parameters to skin reaction was evaluated using chi-square and linear regression tests. The V 100 (volume receiving 100% of prescribed radiation dose, p < 0.001, both axilla and inferior fold) and age (p = 0.039 for axilla and 0.026 for inferior fold) were significant parameters in multivariate analyses. The calculated axilla dose (p = 0.003) and breast separation (p = 0.036) were also risk factors for axilla and inferior fold, respectively. Young age and large V 100 are significant factors for acute skin reaction that can be simply and cost-effectively measured.

Development of a 3D optical scanner for evaluating patient-specific dose distributions.

PURPOSE: This paper describes the hardware and software characteristics of a 3D optical scanner (P3DS) developed in-house. The P3DS consists of an LED light source, diffuse screen, step motor, CCD camera, and scanner management software with 3D reconstructed software. MATERIALS AND METHOD: We performed optical simulation, 2D and 3D reconstruction image testing, and pre-clinical testing for the P3DS. We developed the optical scanner with three key characteristics in mind. First, we developed a continuous scanning method to expand possible clinical applications. Second, we manufactured a collimator to improve image quality by reducing scattering from the light source. Third, we developed an optical scanner with changeable camera positioning to enable acquisition of optimal images according to the size of the gel dosimeter. RESULTS: We confirmed ray-tracing in P3DS with optic simulation and found that 2D projection and 3D reconstructed images were qualitatively similar to the phantom images. For pre-clinical tests, the dose distribution and profile showed good agreement among RTP, optical CT, and external beam radiotherapy film data for the axial and coronal views. The P3DS has shown that it can scan and reconstruct for evaluation of the gel dosimeter within 1 min. We confirmed that the P3DS system is a useful tool for the measurement of 3D dose distributions for 3D radiation therapy QA. Further experiments are needed to investigate quantitative analysis for 3D dose distribution.

Patient performance-based plan parameter optimization for prostate cancer in tomotherapy.

The purpose of this study is to evaluate the influence of treatment-planning parameters on the quality of treatment plans in tomotherapy and to find the optimized planning parameter combinations when treating patients with prostate cancer under different performances. A total of 3 patients with prostate cancer with Eastern Cooperative Oncology Group (ECOG) performance status of 2 or 3 were included in this study. For each patient, 27 treatment plans were created using a combination of planning parameters (field width of 1, 2.5, and 5cm; pitch of 0.172, 0.287, and 0.43; and modulation factor of 1.8, 3, and 3.5). Then, plans were analyzed using several dosimetrical indices: the prescription isodose to target volume (PITV) ratio, homogeneity index (HI), conformity index (CI), target coverage index (TCI), modified dose HI (MHI), conformity number (CN), and quality factor (QF). Furthermore, dose-volume histogram of critical structures and critical organ scoring index (COSI) were used to analyze organs at risk (OAR) sparing. Interestingly, treatment plans with a field width of 1cm showed more favorable results than others in the planning target volume (PTV) and OAR indices. However, the treatment time of the 1-cm field width was 3 times longer than that of plans with a field width of 5cm. There was no substantial decrease in treatment time when the pitch was increased from 0.172 to 0.43, but the PTV indices were slightly compromised. As expected, field width had the most significant influence on all of the indices including PTV, OAR, and treatment time. For the patients with good performance who can tolerate a longer treatment time, we suggest a field width of 1cm, pitch of 0.172, and modulation factor of 1.8; for the patients with poor performance status, field width of 5cm, pitch of 0.287, and a modulation factor of 3.5 should be considered.

Four-dimensional computed tomography based respiratory-gated radiotherapy with respiratory guidance system: analysis of respiratory signals and dosimetric comparison.

PURPOSE: To investigate the effectiveness of respiratory guidance system in 4-dimensional computed tomography (4 DCT) based respiratory-gated radiation therapy (RGRT) by comparing respiratory signals and dosimetric analysis of treatment plans. METHODS: The respiratory amplitude and period of the free, the audio device-guided, and the complex system-guided breathing were evaluated in eleven patients with lung or liver cancers. The dosimetric parameters were assessed by comparing free breathing CT plan and 4 DCT-based 30-70% maximal intensity projection (MIP) plan. RESULTS: The use of complex system-guided breathing showed significantly less variation in respiratory amplitude and period compared to the free or audio-guided breathing regarding the root mean square errors (RMSE) of full inspiration (P = 0.031), full expiration (P = 0.007), and period (P = 0.007). The dosimetric parameters including V(5 Gy), V(10 Gy), V(20 Gy), V(30 Gy), V(40 Gy), and V(50 Gy) of normal liver or lung in 4 DCT MIP plan were superior over free breathing CT plan. CONCLUSIONS: The reproducibility and regularity of respiratory amplitude and period were significantly improved with the complex system-guided breathing compared to the free or the audio-guided breathing. In addition, the treatment plan based on the 4D CT-based MIP images acquired with the complex system guided breathing showed better normal tissue sparing than that on the free breathing CT.

Tumor volume reduction assessed by planning computed tomography in patients with rectal cancer during preoperative chemoradiation: impact of residual tumor volume on the prediction of pathologic tumor regression.

AIMS AND BACKGROUND: To determine whether the residual tumor volume measured using the Eclipse treatment planning system correlates with pathologic tumor regression grade after preoperative chemoradiotherpy for rectal cancer. MATERIALS AND METHODS: The study included 30 patients with rectal cancer who had undergone preoperative chemoradiotherpy followed by surgery from June 2008 to April 2011 at the Korea University Guro Hospital. The tumor volume was measured using the Eclipse treatment planning system in the initial simulation computed tomography and boost planning computed tomography. The correlation between the residual tumor volume in boost planning computed tomography and the pathologic tumor regression grade was analyzed. Tumor regression grade defined in the American Joint Committee on Cancer 7th edition was used. RESULTS: The mean and median residual tumor volume was 57.34% ± 20.37% and 52.35% (range, 18.42%-95.79%), respectively. After surgery, pathologic complete response (tumor regression grade 0) occurred in 4 patients (13.33%), moderate response (tumor regression grade 1) in 18 patients (60%), minimal response (tumor regression grade 2) in 4 patients (13.33%), and poor response (tumor regression grade 3) in 4 patients (13.33%). When residual tumor volume was categorized into two groups (<50% and ≥50%), complete or moderate regression (tumor regression grade 0 or 1) was significantly greater for patients with a residual tumor volume <50% ( P <0.05). The mean residual tumor volume of tumor regression grade 0 or 1 was 49.07% ± 18.39% and that of tumor regression grade 2 or 3 was 76.31% ± 16.94% (P <0.05). CONCLUSIONS: Residual tumor volume measured using routine boost planning computed tomography during preoperative chemoradiotherpy correlated significantly with pathologic tumor regression grade after surgery.

Modified MVAC as a Second-Line Treatment for Patients with Metastatic Urothelial Carcinoma after Failure of Gemcitabine and Cisplatin Treatment.

PURPOSE: There is no established standard second-line chemotherapy for patients with advanced or metastatic urothelial carcinoma (UC) who failed gemcitabine and cisplatin (GC) chemotherapy. This study was conducted in order to investigate the efficacy and toxicity of modified methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) in patients with metastatic UC previously treated with GC. MATERIALS AND METHODS: We retrospectively analyzed 28 patients who received modified MVAC between November 2004 and November 2012. All patients failed prior, first-line GC chemotherapy. RESULTS: The median age of patients was 64.0 years (range, 33.0 to 77.0 years), and 23 (82.1%) patients had an Eastern Cooperative Oncology Group performance status of 0 or 1. The overall response rate and the disease control rate were 36.0% and 64.0%, respectively. After a median follow-up period of 38 weeks (range, 5 to 182 weeks), median progression free survival was 21.0 weeks (95% confidence interval [CI], 6.3 to 35.7 weeks) and median overall survival was 49.0 weeks (95% CI, 18.8 to 79.3 weeks). Grade 3 or 4 hematological toxicities included neutropenia (n=21, 75.0%) and anemia (n=9, 32.1%). Grade 3 or 4 non-hematological toxicities did not occur and there was no treatment-related death. CONCLUSION: Modified MVAC appears to be a safe and active chemotherapy regimen in patients with stable physical status and adequate renal function after GC treatment.

Whole breast irradiation for small-sized breasts after conserving surgery: is the field-in-field technique optimal?

BACKGROUND: To determine the optimal whole breast irradiation technique in patients with small-sized breasts, tangential and field-in-field IMRT (FIF) techniques were compared. METHODS: Sixteen patients with ≤3 cm breast height and ≤350 cc volume were included. Seven patients had 4D CTs performed. The planning target volumes (PTV), editing 5 and 2 mm from the surface on the whole breast, were delineated and called PTV(5) and PTV(2), respectively. Dose-volume histograms of tangential techniques with open beam (OT) and wedge filter (WT), conventional FIF (cFIF), and modified FIF (mFIF) blocking out the lung were produced. Various dose-volume parameters, the dose heterogeneity index (DHtrI), dose homogeneity index (DHmI), and PTV dose improvement (PDI) were calculated. RESULTS: OT compared with WT showed a significantly favorable V 90 of the heart and lung, and PTV(5)-dose distribution. Comparing OT and cFIF, OT showed significant improvement in the V 95 of PTV(2), whereas cFIF showed significant improvement in the V 95, DHtrI, DHmI, and PDI of the PTV(5). In comparing cFIF and mFIF, mFIF showed improved dose distributions of the heart and lung, while cFIF presented the better V 95, DHtrI, DHmI, and PDI of the PTV(5). Respiratory influences on the absolute dose were mostly within 1 %. The ratio of free breathing and each respiratory phase was similar among OT, cFIF, and mFIF. CONCLUSIONS: cFIF has favorable dose conformity and is suggested to be an optimal method for small-sized breasts. However, OT for dose coverage close to the skin and mFIF for normal tissue may also be potential alternatives. Respiratory effects are minimal.

Intraoperative Radiation Therapy for Gallbladder Cancer: Experience at a Single Institution.

BACKGROUND/AIMS: To investigate the survival outcome of intraoperative radiation therapy for patients with gallbladder cancer on the basis of experience at a single institution. METHODOLOGY: The medical records of 8 patients with gallbladder cancer who were treated with intraoperative radiation therapy during surgical resection or palliative surgery were retrospectively analyzed. The primary endpoint was overall survival. The median follow-up time was 20.8 months. RESULTS: The median survival time was 15.0 months. Overall survival for all patients was 75.0% at 1 year, 37.5% at 3 years, and 25.0% at 5 years. Three patients underwent complete resection, and 5 patients had residual tumor after resection or palliative surgery. The 3-year OS rate for 3 patients with no residual tumor after curative resection was 66.7%, with a mean survival time of 122.6 months, whereas the 3-year OS rate for 5 patients with macroscopic residual diseasewas 0% with a mean survival time of 13.5 months (P = 0.014). CONCLUSIONS: The results of the present study suggest that intraoperative radiation therapy with or without external beam radiation therapy was safe and beneficial for patients who underwent curative resection with negative margins and allows the possibility of long-term survival.

Clinical implication of negative conversion of predicted circumferential resection margin status after preoperative chemoradiotherapy for locally advanced rectal cancer.

OBJECTIVE: To evaluate the prognostic implication of the negative conversion of predicted circumferential resection margin status before surgery in patients with locally advanced rectal cancer with predicted circumferential resection margin involvement. METHODS: Thirty-eight patients (28 men, 10 women; median age, 61 years; age range, 39-80 years) with locally advanced rectal cancer with predicted circumferential resection margin involvement who underwent preoperative chemoradiotherapy followed by radical surgery were analyzed. Involvement of the circumferential resection margin was predicted on the basis of pre- and post-chemoradiotherapy magnetic resonance imaging. The primary endpoints were 3-year local recurrence-free survival and overall survival. RESULTS: The median follow-up time was 41.1 months (range, 13.9-85.2 months). The negative conversion rate of predicted circumferential resection margin status after preoperative chemoradiotherapy was 65.8%. Patients who experienced negative conversion of predicted circumferential resection margin status had a significantly higher 3-year local recurrence-free survival rate (100.0% vs. 76.9%; P=0.013), disease-free survival rate (91.7% vs. 59.3%; P=0.023), and overall survival rate (96.0% vs. 73.8%; P=0.016) than those who had persistent circumferential resection margin involvement. CONCLUSIONS: The negative conversion of the predicted circumferential resection margin status as predicted by magnetic resonance imaging will assist in individual risk stratification as a predictive factor for treatment response and survival before surgery. These findings may help physicians determine whether to administer more intense adjuvant chemotherapy or change the surgical plan for patients displaying resistance to preoperative chemoradiotherapy.

Can intensity-modulated radiation therapy spare the central flapped area while encompassing the target volume in radiotherapy after immediate breast reconstruction?

INTRODUCTION: Radiotherapy increases the morbidity of immediate breast reconstruction. To spare the flapped area without an adverse dose distribution of the target volume and organ at risks, various radiation techniques were assessed. METHODS: Twelve breasts undergoing skin-sparing mastectomy and immediate transverse rectus abdominis myocutaneous flap reconstruction were evaluated. After a delineation of whole breast, the doughnut-like breast target volume (BTV) including the chest wall and skin and the subtracted central flapped volume (FV) were defined. The opposed wedge tangential radiotherapy (3-dimensional conformal radiotherapy (3-D CRT) ), field-in-field radiotherapy (FiF), inverse intensity-modulated radiotherapy (iIMRT), volumetric modulated arc radiotherapy (VMRT) and the mixture of FiF and iIMRT (HYBRID) were tried. Total 50 Gy was prescribed to the BTV. The paired student t-tests were performed. RESULTS: The V47.5Gy of the BTV was improved in iIMRT and VMRT compared with 3-D CRT and FiF. The mean FV doses in iIMRT and VMRT were 76.7 ± 3.9% and 85.5 ± 4.0%, respectively. However the mean ipsilateral lung doses were aggravated by iIMRT and VMRT. In terms of HYBRID, the V47.5Gy for the BTV was 97.5 ± 0.7%. The mean FV dose was 89.4 ± 2.1%. While the mean FV dose in HYBRID was 13.7 ± 2.1% (P < 0.001) lower than FiF, it was 12.8 ± 1.9% (P < 0.001) higher than iIMRT. The mean ipsilateral lung dose in HYBRID was 2.8 ± 1.9% (P < 0.001) worse than FiF, and 2.6 ± 1.8% (P < 0.001) better than iIMRT. CONCLUSIONS: The HYBRID could minimise the adverse dose distribution of lung and reduce 10% of the mean dose to the flapped area. For patients with adverse factors for the failure of breast reconstruction, the HYBRID could be considered.

Combination of gemcitabine and carboplatin as first line treatment in elderly patients or those unfit for cisplatin-based chemotherapy with advanced transitional cell carcinoma of the urinary tract.

PURPOSE: Although cisplatin-based chemotherapy is the standard of care for advanced transitional cell carcinoma, tolerability is a challenging issue in unfit patients. This study was conducted to evaluate the efficacy, toxicity, and tolerability of the combination of gemcitabine and carboplatin in unfit patients with advanced transitional cell carcinoma. METHODS: Thirty-one patients who had advanced transitional cell carcinoma and one of the following clinical features were evaluated: Eastern Cooperative Oncology Group performance status equal or greater than 2, age older the 75 years or estimated glomerular filtration rate less than 60 ml/min. The patients were treated with carboplatin and gemcitabine delivered every 4 weeks. RESULTS: Of the 31 patients, 71 % had an estimated glomerular filtration rate of less than 60 ml/min, and the remaining patients were treated by this protocol due to poor performance status or age older than 75. The median age of the patients was 74 years old. A total of 162 cycles of treatment were delivered to the patients. The overall response rate was 45.1 %. After the median follow-up of 15 months, the median progression-free survival time was 9.4 months (95 % CI 7.3-11.4) and overall survival time was 20 months (95 % CI 14.9-25.0). Grades 3 and 4 anemia, thrombocytopenia, and neutropenia were observed in 22.6, 6.45, and 6.45 % of patients, respectively. There was no treatment-related mortality in our patient series. CONCLUSION: The combination of gemcitabine and carboplatin is effective in elderly patients with advanced transitional cell carcinoma or those unfit for cisplatin-based chemotherapy, with manageable toxicity.

Sequential chemotherapy followed by radiotherapy versus concurrent chemoradiotherapy in patients with stage I/II extranodal natural killer/T-cell lymphoma, nasal type.

BACKGROUND: The purpose of this report is to summarize our clinical experience of patients with stage I/II extranodal natural killer (NK)/T-cell lymphoma, nasal type, treated using sequential chemotherapy followed by radiotherapy (SCRT) or concurrent chemoradiotherapy (CCRT). METHODS: Forty-three patients with stage I/II extranodal NK/T-cell lymphoma, nasal type, who received SCRT (16 patients) or CCRT (27 patients) were included in the present analysis. RESULTS: The median follow-up time was 39 months (range, 4-171 months) for all patients, 77 months (range, 4-171 months) for the SCRT group, and 31 months (range, 6-132 months) for the CCRT group. There were no statistically significant differences between the SCRT and CCRT groups with regard to the 3-year progression-free survival (PFS) (56% vs. 41%, P=0.823) and 3-year overall survival (OS) (75% vs. 59%, P=0.670). Univariate analysis revealed that patients with tumors confined to the nasal cavity and patients achieved complete remission had better PFS and OS rates, regardless of the treatment sequence. Multivariate analysis revealed that patients with tumors confined to the nasal cavity and patients aged ≤60 years had better OS rates. CONCLUSION: The effect of SCRT and CCRT are similar in terms of survival outcomes of patients with stage I/II extranodal NK/T-cell lymphoma, nasal type. Our results show that tumors confined to the nasal cavity and an age ≤60 years were associated with a better prognosis.

Evaluation of mechanical accuracy for couch-based tracking system (CBTS).

This study evaluated the mechanical accuracy of an in-house-developed couch-based tracking system (CBTS) according to respiration data. The overall delay time of the CBTS was calculated, and the accuracy, reproducibility, and loading effect of the CBTS were evaluated according to the sinusoidal waveform and various respiratory motion data of real patients with and without a volunteer weighing 75kg. The root mean square (rms) error of the accuracy, the reproducibility, and the sagging measurements were calculated for the three axes (X, Y, and Z directions) of the CBTS. The overall delay time of the CBTS was 0.251 sec. The accuracy and reproducibility in the Z direction in real patient data were poor, as indicated by high rms errors. The results of the loading effect were within 1.0 mm in all directions. This novel CBTS has the potential for clinical application for tumor tracking in radiation therapy.