No clinically significant changes in pulmonary function following stereotactic body radiation therapy for early- stage peripheral non-small cell lung cancer: an analysis of RTOG 0236.

PURPOSE: To investigate pulmonary function test (PFT) results and arterial blood gas changes (complete PFT) following stereotactic body radiation therapy (SBRT) and to see whether baseline PFT correlates with lung toxicity and overall survival in medically inoperable patients receiving SBRT for early stage, peripheral, non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: During the 2-year follow-up, PFT data were collected for patients with T1-T2N0M0 peripheral NSCLC who received effectively 18 Gy × 3 in a phase 2 North American multicenter study (Radiation Therapy Oncology Group [RTOG] protocol 0236). Pulmonary toxicity was graded by using the RTOG SBRT pulmonary toxicity scale. Paired Wilcoxon signed rank test, logistic regression model, and Kaplan-Meier method were used for statistical analysis. RESULTS: At 2 years, mean percentage predicted forced expiratory volume in the first second and diffusing capacity for carbon monoxide declines were 5.8% and 6.3%, respectively, with minimal changes in arterial blood gases and no significant decline in oxygen saturation. Baseline PFT was not predictive of any pulmonary toxicity following SBRT. Whole-lung V5 (the percentage of normal lung tissue receiving 5 Gy), V10, V20, and mean dose to the whole lung were almost identical between patients who developed pneumonitis and patients who were pneumonitis-free. Poor baseline PFT did not predict decreased overall survival. Patients with poor baseline PFT as the reason for medical inoperability had higher median and overall survival rates than patients with normal baseline PFT values but with cardiac morbidity. CONCLUSIONS: Poor baseline PFT did not appear to predict pulmonary toxicity or decreased overall survival after SBRT in this medically inoperable population. Poor baseline PFT alone should not be used to exclude patients with early stage lung cancer from treatment with SBRT.

Matched-pair and propensity score comparisons of outcomes of patients with clinical stage I non-small cell lung cancer treated with resection or stereotactic radiosurgery.

BACKGROUND: Stereotactic body radiotherapy (SBRT) is an alternative to surgery for clinical stage I non-small cell lung cancer (NSCLC), but comparing its effectiveness is difficult because of differences in patient selection and staging. METHODS: Two databases were combined which contained patients treated from 1999 to 2008 by lobectomy (LR, n = 132), sublobar resection (SLR, n = 48), and SBRT (n = 137) after negative staging. Univariate and multivariate analysis were performed for survival (OS), total recurrence control (TRC comprises local-regional and distant control), and locoregional control (LRC) in our entire population. A matched-pair analysis was also performed that compared surgery and SBRT results. Median follow-up for the entire study population was 25.8 months. RESULTS: On univariate analysis, OS was significantly worse with SBRT and also correlated with histology, the Charlson comorbidity index, tumor size, and aspirin use; TRC correlated only with histology; and no variable significantly correlated with LRC. OS was significantly poorer for SBRT in the matched-pair analysis than for patients treated with surgery, but TRC and LRC were not significantly different between these groups. Multivariate analyses including propensity score as a covariate (controlling for all factors affecting treatment selection) found that OS correlated only with Charlson comorbidity index, and TRC correlated only with tumor grade. LRC correlated only with tumor size with or without propensity score correction. CONCLUSIONS: This retrospective study has demonstrated similar OS, LRC, and TRC with SBRT or surgery after controlling for prognostic and patient selection factors. Randomized clinical trials are needed to better compare the effectiveness of these treatments.

Predicting radiation pneumonitis after chemoradiation therapy for lung cancer: an international individual patient data meta-analysis.

BACKGROUND: Radiation pneumonitis is a dose-limiting toxicity for patients undergoing concurrent chemoradiation therapy (CCRT) for non-small cell lung cancer (NSCLC). We performed an individual patient data meta-analysis to determine factors predictive of clinically significant pneumonitis. METHODS AND MATERIALS: After a systematic review of the literature, data were obtained on 836 patients who underwent CCRT in Europe, North America, and Asia. Patients were randomly divided into training and validation sets (two-thirds vs one-third of patients). Factors predictive of symptomatic pneumonitis (grade ≥2 by 1 of several scoring systems) or fatal pneumonitis were evaluated using logistic regression. Recursive partitioning analysis (RPA) was used to define risk groups. RESULTS: The median radiation therapy dose was 60 Gy, and the median follow-up time was 2.3 years. Most patients received concurrent cisplatin/etoposide (38%) or carboplatin/paclitaxel (26%). The overall rate of symptomatic pneumonitis was 29.8% (n=249), with fatal pneumonitis in 1.9% (n=16). In the training set, factors predictive of symptomatic pneumonitis were lung volume receiving ≥20 Gy (V(20)) (odds ratio [OR] 1.03 per 1% increase, P=.008), and carboplatin/paclitaxel chemotherapy (OR 3.33, P<.001), with a trend for age (OR 1.24 per decade, P=.09); the model remained predictive in the validation set with good discrimination in both datasets (c-statistic >0.65). On RPA, the highest risk of pneumonitis (>50%) was in patients >65 years of age receiving carboplatin/paclitaxel. Predictors of fatal pneumonitis were daily dose >2 Gy, V(20), and lower-lobe tumor location. CONCLUSIONS: Several treatment-related risk factors predict the development of symptomatic pneumonitis, and elderly patients who undergo CCRT with carboplatin-paclitaxel chemotherapy are at highest risk. Fatal pneumonitis, although uncommon, is related to dosimetric factors and tumor location.

Chest wall toxicity after stereotactic body radiotherapy for malignant lesions of the lung and liver.

PURPOSE: To quantify the frequency of rib fracture and chest wall (CW) pain and identify the dose-volume parameters that predict CW toxicity after stereotactic body radiotherapy (SBRT). METHODS AND MATERIALS: The records of patients treated with SBRT between 2000 and 2008 were reviewed, and toxicity was scored according to Common Terminology Criteria for Adverse Events v3.0 for pain and rib fracture. Dosimetric data for CW and rib were analyzed and related to the frequency of toxicity. The risks of CW toxicity were then further characterized according to the median effective concentration (EC(50)) dose-response model. RESULTS: A total of 347 lesions were treated with a median follow-up of 19 months. Frequency of Grade I and higher CW pain and/or fracture for CW vs. non-CW lesions was 21% vs. 4%, respectively (p < 0.0001). A dose of 50 Gy was the cutoff for maximum dose (Dmax) to CW and rib above which there was a significant increase in the frequency of any grade pain and fracture (p = 0.03 and p = 0.025, respectively). Volume of CW receiving 15 Gy - 40 Gy was highly predictive of toxicity (R(2) > 0.9). According to the EC(50) model, 5 cc and 15 cc of CW receiving 40 Gy predict a 10% and 30% risk of CW toxicity, respectively. CONCLUSION: Adequate tumor coverage remains the primary objective when treating lung or liver lesions with SBRT. To minimize toxicity when treating lesions in close proximity to the CW, Dmax of the CW and/or ribs should remain <50 Gy, and <5 cc of CW should receive ≥ 40 Gy.

Phosphorus-32 therapy for cystic craniopharyngiomas.

BACKGROUND AND PURPOSE: To examine control rates for predominantly cystic craniopharyngiomas treated with intracavitary phosphorus-32 (P-32). MATERIAL AND METHODS: 22 patients with predominantly cystic craniopharyngiomas were treated at Indiana University between October 1997 and December 2006. Nineteen patients with follow-up of at least 6 months were evaluated. The median patient age was 11 years, median cyst volume was 9 ml, a median dose of 300 Gy was prescribed to the cyst wall, and median follow-up was 62 months. RESULTS: Overall cyst control rate after the initial P-32 treatment was 67%. Complete tumor control after P-32 was 42%. Kaplan-Meier 1-, 3-, and 5-year initial freedom-from-progression rates were 68%, 49%, and 31%, respectively. Following salvage therapy, the Kaplan-Meier 1-, 3-, and 5-year ultimate freedom-from-progression rates were 95%, 95%, and 86%, respectively. All patients were alive at the last follow-up. Visual function was stable or improved in 81% when compared prior to P-32 therapy. Pituitary function remained stable in 74% of patients following P-32 therapy. CONCLUSIONS: Intracystic P-32 can be an effective and tolerable treatment for controlling cystic components of craniopharyngiomas as a primary treatment or after prior therapies, but frequently allows for progression of solid tumor components. Disease progression in the form of solid tumor progression, re-accumulation of cystic fluid, or development of new cysts may require further radiotherapy or surgical intervention for optimal long-term disease control.

Treatment of anal carcinoma in immune-compromised patients.

BACKGROUND: Immune-compromised populations show an increased incidence of anogenital tract neoplasms. This study was undertaken to evaluate local control (LC), overall survival (OS) and toxicity in immune-compromised patients with anal carcinoma treated with radiotherapy with or without chemotherapy. METHODS: We identified 25 patients with anal carcinoma and human immunodeficiency virus (HIV) infection or history of solid-organ transplant on chronic medical immune-suppression. Median age and follow-up were 44 years and 26 months respectively. AJCC T-stages were Tis (4%), T1 (8%), T2 (58%) and T3 (29%). N-stages were N0 (79%), N1 (4%), N2 (13%) and N3 (4%). One patient had metastatic disease at diagnosis. Seventy-five percent received concurrent chemoradiotherapy. Median radiation dose to the primary tumour was 50 Gy. RESULTS: One-, 3- and 5-year LC without salvage therapy was 87%, 87% and 70% respectively. One-, 3- and 5-year actuarial OS was 96%, 73% and 61% respectively. One-, 3- and 5-year OS was 100% for treatment time (TT) <50 days and 57%, 38% and 0% for TT > or =50 days (p=0.0009). All patients had acute grade 2-3 skin toxicity. Acute grade 3-4 gastrointestinal (GI), genitourinary (GU) and haematological toxicity occurred in 8%, 0% and 38%. Late grade 3-4 skin, GI and GU toxicity occurred in 8%, 4% and 0%. CONCLUSIONS: Most HIV-positive and organ transplant patients receiving radiotherapy with or without chemotherapy experience acute toxicity but few have chronic complications. T-stage and CD4 level in HIV-positive patients predict for LC. T-stage and TT predict for OS.