Search

Background Radiotherapy (RT) is an effective treatment for elderly patients with locally advanced non-small-cell lung cancer (NSCLC); however, no clinical trials have investigated combination RT with pemetrexed (PEM) in chemotherapy-naive patients ≥71 years old. We conducted a phase I/II study to evaluate the appropriate PEM dose, efficacy, and safety of PEM plus RT in elderly patients. Methods Patients ≥71 years with performance status (PS) scores of 0–2 who had pathologically confirmed stage IIIA/IIIB NSCLC received PEM (500 mg/m2 on day 1 of a 28-day cycle, 4 courses) and RT (a single 2 Gy daily fraction on 5 consecutive days weekly from day 1; 60 Gy total). The primary endpoint was the objective response rate (ORR); the secondary endpoints were progression-free survival (PFS), overall survival (OS), and adverse events (AEs). Results Forty-one patients with a median age of 79 years were enrolled; 31 were men. Eighteen patients had squamous cell carcinoma, 27 had stage IIIA disease, and 38 had PS scores 0–1. The ORR was 80.5%, while the median OS and PFS rates were 24.9 and 6.9 months, respectively. Two treatment-related deaths occurred owing to RT-related pneumonitis and severe infection, respectively. Common hematological AEs were leucopenia and neutropenia; common non-hematological AEs were anorexia and constipation. Three patients developed PEM-induced interstitial lung disease; however, most AEs were RT-related. Conclusions Combination PEM and RT shows promising efficacy but relatively severe RT-related toxicities. Therefore, this treatment should be prescribed to elderly patients with caution. UMIN 000005036 .

The purpose of this study was to perform dosimetry analyses comparing high-dose-rate brachytherapy (HDR-BT) with simulated stereotactic body radiotherapy (SBRT). We selected six consecutive patients treated with HDR-BT monotherapy in 2010, and a CyberKnife SBRT plan was simulated for each patient using computed tomography images and the contouring set used in the HDR-BT plan for the actual treatment, but adding appropriate planning target volume (PTV) margins for SBRT. Then, dosimetric profiles for PTVs of the rectum, bladder and urethra were compared between the two modalities. The SBRT plan was more homogenous and provided lower dose concentration but better coverage for the PTV. The maximum doses in the rectum were higher in the HDR-BT plans. However, the HDR-BT plan provided a sharper dose fall-off around the PTV, resulting in a significant and considerable difference in volume sparing of the rectum with the appropriate PTV margins added for SBRT. While the rectum D5cm(3) for HDR-BT and SBRT was 30.7 and 38.3 Gy (P < 0.01) and V40 was 16.3 and 20.8 cm(3) (P < 0.01), respectively, SBRT was significantly superior in almost all dosimetric profiles for the bladder and urethra. These results suggest that SBRT as an alternative to HDR-BT in hypofractionated radiotherapy for prostate cancer might have an advantage for bladder and urethra dose sparing, but for the rectum only when proper PTV margins for SBRT are adopted.

Purpose The actual dose delivered to critical organs will differ from the simulated dose because of interfractional organ motion and deformation. Here, we developed a method to estimate the rectal dose in prostate intensity modulated radiation therapy with consideration to interfractional organ motion using daily megavoltage cone-beam computed tomography (MVCBCT). Methods and Materials Under exemption status from our institutional review board, we retrospectively reviewed 231 series of MVCBCT of 8 patients with prostate cancer. On both planning CT (pCT) and MVCBCT images, the rectal contours were delineated and the CT value within the contours was replaced by the mean CT value within the pelvis, with the addition of 100 Hounsfield units. MVCBCT images were rigidly registered to pCT and then nonrigidly registered using B-Spline deformable image registration (DIR) with Velocity AI software. The concordance between the rectal contours on MVCBCT and pCT was evaluated using the Dice similarity coefficient (DSC). The dose distributions normalized for 1 fraction were also deformed and summed to estimate the actual total dose. Results The DSC of all treatment fractions of 8 patients was improved from 0.75±0.04 (mean ±SD) to 0.90 ±0.02 by DIR. Six patients showed a decrease of the generalized equivalent uniform dose (gEUD) from total dose compared with treatment plans. Although the rectal volume of each treatment fraction did not show any correlation with the change in gEUD (R 2 =0.18±0.13), the displacement of the center of gravity of rectal contours in the anterior-posterior (AP) direction showed an intermediate relationship (R 2 =0.61±0.16). Conclusion We developed a method for evaluation of rectal dose using DIR and MVCBCT images and showed the necessity of DIR for the evaluation of total dose. Displacement of the rectum in the AP direction showed a greater effect on the change in rectal dose compared with the rectal volume.

Introduction: The Abscopal effect refers to radiotherapy-induced tumor regression in lesions distant from a targeted site, and is a rare phenomenon in patients receiving local radiotherapy. This report is the first to describe an Abscopal response in a chemotherapy-naive non-small cell lung cancer (NSCLC) patient following whole-brain radiotherapy as well as palliative radiotherapy. Case presentation: A 63-years-old man who was a current-smoker (with 86 pack years) with metastatic NSCLC underwent whole brain radiotherapy (WBRT) plus boost radiotherapy to total dose of 45 Gy in 15 fractions because the metastatic brain tumor with cerebral oedema from the left temporal lobe to the occipital lobe rapidly progressed after the enucleation of the brain tumor. The patient also received palliative radiation (30 Gy in 10 fractions) for the third lumbar vertebral metastasis. The tumor in the left upper lobe of the lung and his mediastinal lymph nodes had regressed in size upon reviewing his follow-up CT results seven weeks post-radiotherapy. Conclusion: The Abscopal effect in metastatic NSCLC patients can occur after the irradiation of metastatic lesions without chemotherapeutic or immunotherapeutic interventions.

To evaluate the correlation between dosimetric parameters and late rectal and urinary toxicities in high-dose-rate brachytherapy (HDR-BT) used as monotherapy for prostate cancer.The data of 83 patients treated with HDR-BT alone for prostate cancer from 2001 through 2005 at Osaka University Hospital were analyzed. Median follow-up time was 36 months (range, 18-70). The total prescribed dose was 54 Gy in nine fractions over 5 days. Correlation between dosimetric parameters and late toxicities was examined.The means of V30, V40, V50, V60, V70, D1cc, D2cc, D5cc, and D10cc of the rectum were significantly higher in 18 patients who presented with late rectal toxicity (Grades 1-3 rectal bleeding) than in the other 65 patients who did not. A significant difference was observed for D1cc-10cc but not for D5-90. The statistically most significant difference was observed for V40 and D5cc. Late rectal toxicity rate was significantly higher for patients with rectal V40or= 8 cc than those with the rectal V408 cc (42% vs. 8%; p0.001), as well as for patients with rectal D5ccor= 27 Gy compared with those with rectal D5cc27 Gy (50% vs. 11%; p0.001). Dosimetric parameters of the urethra of 15 patients with late urinary toxicity were not significantly different from the 68 patients without toxicity.Rectal V408 cc and D5cc27 Gy may be dose-volume constraints in HDR-BT used as monotherapy for prostate cancer.

Background: To investigate the treatment results of intracranial meningiomas treated with hypofractionated stereotactic radiation therapy in three to five fractions. Methods: Thirty-one patients (32 lesions) with intracranial meningioma were treated with hypofractionated stereotactic radiation therapy in three to five fractions using CyberKnife. Fifteen lesions were diagnosed as Grade I (World Health Organization classification) by surgical resection and 17 lesions were diagnosed as meningioma based on radiological findings. The median follow-up time was 48 months. The median planning target volume was 6.3 cm 3 (range, 1.4‐27.1), and the prescribed dose (D90� ) ranged from 21 to 36 Gy (median, 27.8) administrated in three to five fractions. Results: Five-year overall and progression-free survival rate of all 31 patients with intracranial meningioma was 86 and 83%, respectively. Five-year progression-free rate of all 32 lesions was 87%. Six of the 31 patients (19%) developed marked peritumoral edema, three of whom were asymptomatic and three symptomatic, the latter with late adverse effects of more than or equal to Grade 3. The mean planning target volume of the six lesions with marked peritumoral edema was 15.6 cm 3 , and for the remaining 26 lesions without marked peritumoral edema was 7.1 cm 3 (P ¼ 0.004). The threshold diameter of 2.56 cm for meningioma was calculated from the planning target volume (11 cm 3 ) and was used as marker of developing peritumoral edema (P ¼ 0.003). Conclusions: Tumor volume is a significant indicative factor for peritumoral edema in intracranial meningioma treated with hypofractionated stereotactic radiation therapy in three to five factions.

Purpose The aim of the study was to evaluate the results of high-dose-rate interstitial brachytherapy (HDR-ISBT) for patients with advanced cervical carcinoma in which intracavitary radiation therapy may result in a suboptimal dose distribution. Methods and Materials Between 1995 and 2005, 25 patients of median age 64 years were treated with external beam radiation therapy and HDR-ISBT. The International Federation of Gynecology and Obstetrics stages of the patients were I (4%), II (16%), III (68%), and IVA (12%). Whole pelvic irradiation of 30 Gy/15 fractions was followed by HDR-ISBT of 30 Gy/5 fractions/3 days. Subsequently, additional pelvic external beam radiation therapy of 20 Gy/10 fractions was delivered with a midline block. The median followup period was 55 months. Results The actuarial 5-year progression-free survival and overall survival rates for all cases were 42% and 54%, respectively. For the 17 patients with a Stage III tumor, the 5-year local control and overall survival rates were 73% and 51%, respectively. Two patients (8%) developed late toxicities of Grade 3. Conclusions A high rate of pelvic control and survival with acceptable level of late toxicities were obtained for patients with advanced cervical carcinoma treated with HDR-ISBT.

Purified tubular membranes prepared by extracting rat skeletal muscle cell fragments with buffered 0.4 M LiBr solution have been shown by electron microscopy to retain the major three layers (outer network of collagen fibrils, middle basement membrane, and inner plasma membrane) of the sarcolemma of the intact muscle cell. A chloroformmethanol mixture destroyed the plasma membrane, thereby extracting steroid, glyceride, phosphatide, protein and carbohydrate. A collagenase (EC 3.4.4.19) preparation appeared to digest not only the collagen network, but also the basement membrane. The lipid extractio or collagenase treatment did not destroy the tubular structure of the isolated membrane, but successive application of both treatments yielded only an amorphous precipitate.