Polly Nobiensky

Toxicity analysis of postoperative image-guided intensity-modulated radiotherapy for prostate cancer.

PURPOSE To report on the acute and late gastrointestinal (GI) and genitourinary (GU) toxicity associated with a unique technique of image-guided radiotherapy (IGRT) in patients undergoing postprostatectomy irradiation. METHODS AND MATERIALS Fifty patients were treated with intensity-modulated radiation therapy (IMRT) after radical prostatectomy. Daily image guidance was performed to localize the prostate bed using kilovoltage imaging or cone-beam computed tomography. The median prescription dose was 68 Gy (range, 62-68 Gy). Toxicity was graded every 3 to 6 months according to the Common Terminology Criteria for Adverse Events version 3.0. RESULTS The median follow-up was 24 months (range, 13-38 months). Grade 2 acute GI and GU events occurred in 4 patients (8%) and 7 patients (14%), respectively. No Grade 3 or higher acute GI or GU toxicities were observed. Late Grade 2 GI and GU events occurred in 1 patient (2%) and 8 patients (16%), respectively. Only a single (2%) Grade 3 or higher late toxicity was observed. CONCLUSIONS Image-guided IMRT in the postprostatectomy setting is associated with a low frequency of acute and late GI/GU toxicity. These results compare more favorably to radiotherapy techniques that do not use in-room image-guidance, suggesting that daily prostate bed localization may reduce the incidence of adverse events in patients undergoing postprostatectomy irradiation.

Locoregional and distant failure following image-guided stereotactic body radiation for early-stage primary lung cancer

PURPOSE To report our institutional experience using image-guided stereotactic body radiation therapy (SBRT) for early stage lung cancer, including an analysis into factors associated with nodal and distant failures (NF, DF). METHODS Forty-eight patients with early-stage primary lung cancer were treated with image-guided SBRT between 2007 and 2009. Median prescription dose was 48 Gy in 4 fractions. Toxicity was graded according to the NCI CTCAE v3.0 scale. RESULTS Local failure was detected in two lesions and actuarial 24-month local control was 95%. At 24 months, the cumulative incidence of NF was 6%, and DF was 29%. Larger lesions (>3 cm) and younger age (<70 years) were the only factors found to be significantly correlated with increased DF (p=0.005 and p=0.015, respectively). A single grade ≥ 3 toxicity was observed. After adjusting for age and lesion size, distant failure was significantly associated with a poorer OS (Cox regression, p=0.0059). CONCLUSION Image-guided SBRT can produce excellent LC rates with minimal toxicity. Distant failure was a major determinant of OS and the most common pattern of failure, indicating a potential role for systemic therapy in younger patients with large lesions.

Frameless Image-Guided Stereotactic Body Radiation Therapy for Lung Tumors with 4-Dimensional Computed Tomography or 4-Dimensional Positron Emission Tomography/ Computed Tomography

BACKGROUND/PURPOSE To augment the accuracy of stereotactic body radiation therapy (SBRT), a variety of image guidance systems are used for patient positioning and target localization. Clinical outcomes evaluating these systems, especially frameless image-guided systems, are still limited. This article aims to describe and evaluate our frameless image-guided SBRT technique for lung tumors. METHODS Between 2007 and 2009, 85 pulmonary tumors (50 primaries and 35 metastases) were treated with SBRT using daily image guidance for patient positioning and target localization in lieu of a body frame. Four-dimensional computed tomography (4DCT) or an in-house protocol for integrated 4D positron emission computed tomography (4DPET/CT) was used for planning simulation. RESULTS Median follow-up was 17 months (range, 4-42). Median overall survival (OS) was 31 months (95% CI, 26-34), and median local failure-free survival was 30 months (95% CI, 18-32). At last follow-up, 9 of 83 evaluable lesions failed locally. Actuarial local control at 24 months was 87% (95% CI, 75-98) and was significantly worse for metastatic lesions (95% vs. 74%; P = .045; log-rank test). No acute or late toxicities (grade ≥ 4) were observed. CONCLUSIONS Frameless image-guided SBRT is a feasible, safe, and effective treatment for lung tumors.

Hypofractionated radiotherapy as definitive treatment of stage I non-small cell lung cancer in older patients.

Purpose/Objective(s): We report our experience using hypofractionated radiotherapy in older patients. Materials/Methods: This analysis includes patients aged 60 years and older at our institution with inoperable Stage I (T1/T2 N0 M0) non–small-cell lung cancer that completed a curative course of radiotherapy alone using a hypofractionated schedule. Between 1991 and 2006, 75 such patients were identified with median age of 74 years (range, 60–86). Patient characteristics were as follows: male, 65/75 (86.7%); stage IA (T1N0), 47/75 (62.7%); stage IB (T2N0), 28/75 (37.3%). Patients received a median total dose of 6500 cGy using median daily dose fractions of 250 cGy. The following outcomes were analyzed: local failure free survival (time to local failure or death from any cause), time to distal failure as first event, and overall survival. Toxicities were evaluated using Common Terminology Criteria for Adverse Events v 3.0. Results: The median follow-up was 19.6 months (range: 4.0–128.8 months). Median local failure free survival was 19.6 months (95% confidence interval [CI]: 14.4–28.8 months); and median overall survival was 21.2 months (95% CI: 14.9–29.3 months). Analysis of competing risks showed that at 5 years, the probability of local failure as the first detected event was 22.1% (95% CI: 12.8%–32.9%); the probability of distal failure as the first detected event was 14.5% (95% CI: 7.3%–24.0%); and the probability of death without recording a failure was 48.6% (95% CI: 36.1%–60.1%). Radiation-related toxicity of grade 3 or greater was seen in 3 patients and there were no treatment-related deaths. Conclusions: Hypofractionated radiotherapy is an effective, safe treatment for older patients with stage I non–small-cell lung cancer.

The role of positron emission tomography following radiosurgical treatment of malignant lung lesions.

Objective To establish response patterns in PET following stereotactic body radiotherapy (SBRT) of malignant lung lesions. Methods Patients with malignant lung lesions treated with SBRT were retrospectively reviewed. All patients received 40–52 Gy in three to five equal fractions. An independent, blinded radiologist reassessed all 18F-fluoro-deoxy-glucose PET/computed tomography scans to determine the tumor maximum standardized uptake value (SUVmax) and size changes. Results Thirty-nine patients were included in this study. Of the 47 lesions treated, there were 22 primary and 25 metastatic lung lesions. In total, 86 PET/computed tomography studies were reviewed. The mean SUVmax values decreased markedly and stabilized after 6 months following the treatment of primary lesions. Metastatic lesions showed greater variability, with an overall increase in SUVmax values until 6 months and decrease thereafter. Of the eight local failures, the mean SUVmax and size change from nadir values to biopsy-proven failure were 117 and 215%; however, it was difficult to measure the size of five lesions because of fibrotic changes. Statistical analysis revealed metastatic tumors to be associated with poorer local control (P=0.028). No correlation was found between size or pretreatment SUVmax and outcome. Conclusion Anticipated SUVmax and size patterns following SBRT remain a challenge due to surrounding tissue reactions. Nonetheless, marked SUVmax changes can aid in determining local failure. Increases in size were also observed in local failures; however, localized fibrosis challenges its utility in distinguishing failures from a normal tissue response. A larger series needs to be examined to better establish the correlation of PET responses to overall survival and local control.

Conformal Radiation Therapy as Definitive Treatment of Stage I Non—Small-Cell Lung Cancer: University of California San Diego Experience

Abstract Purpose Surgical resection remains the treatment of choice for patients with stage I non—small-cell lung cancer (NSCLC). However, there is high likelihood of medical comorbidity in this patient population, requiring management by nonsurgical approaches. We report our experience using conventional and hypofractionated radiation therapy schedules with conformal approach. Patients and Methods Between 1991 and 2006, 108 patients with medically or otherwise inoperable stage T1/T2 N0 NSCLC were treated with curative radiation therapy alone at our institution. Patient characteristics were as follows: median age, 73 years (range, 37–86 years); male, 88/108 (81.5%); stage T2, 46/108 (42.6%), and histology/cytology, 91/108 (84.3%). Patients received a median total dose of 6500 cGy using median daily dose fractions of 250 cGy. The majority of patients were treated using hypofractionated schedules: daily dose fractions > 200 cGy, 79/108 (73.1%). The following outcomes were analyzed: local failure-free survival (LFFS; time to local failure or death from any cause), time to local or distal failure as first event, and overall survival (OS). Local failure was defined as an increase in size on imaging studies. Toxicities were evaluated using Common Terminology Criteria for Adverse Events v3.0. Results Median follow-up was 19.9 months (range, 4–138.9 months). Median LFFS was 20.8 months (95% CI, 15.1–24.3 months), and median OS was 20.9 months (95% CI, 17.1–27.2 months). Analysis of competing risks showed that, at 5 years, the probability of local failure as the first detected event was 17.1% (95% CI, 10.3–25.3%), the probability of distal failure as the first detected event was 17.9% (95% CI, 11–26.1%), and the probability of death without recording a failure was 50.7% (95% CI, 40.1–60.3%). Patients aged ≥ 70 years had higher probability of death without recording a failure within 5 years (55.5%; 95% CI, 41.7% −67.3%) than patients aged Conclusion Conformal radiation therapy is an effective and safe alternative to surgery for patients with stage I NSCLC. The results are limited because this is a single-institution observational study. Nevertheless, a large majority of patients remained free of local recurrence and without significant clinical toxicity.