Cristina Mantovani

Stereotactic body radiation therapy for early stage non-small cell lung cancer: Results of a prospective trial

Patients affected with early stage (IA-IB) non-small cell lung cancer (NSCLC), deemed medically inoperable, are usually treated by conventional 3D-CRT, with poor results in terms of local tumour control and survival. Hypofractionated stereotactic body radiation therapy (SBRT) appears to be a valid alternative option, with high rates of local control and promising survival rates according to recent reported series. We herein report the final results of a prospective phase II trial of SBRT in 62 stage I NSCLC patients, homogeneously treated with three fractions of 15Gy each, given every other day during a 1 week time, up to a total dose of 45Gy; dose was prescribed to the 80%-isodose encompassing planning target volume. Patients were immobilized in a dedicated stereotactic body frame; margins around gross tumour volume were 5mm in the axial plane and 10mm in the longitudinal direction. Median age was 73.7 years. A pathologic confirmation of NSCLC was obtained in 64.5% of patients. Forty-three patients had stage IA and 19 stage IB disease. The majority of patients did not experience any toxicity; mild skin reactions, fatigue, dyspnea/cough or transient thoracic pain were recorded in approximately 10% of patients. With a median follow-up time of 28 months, 2 patients experienced an isolated local relapse, 4 an isolated nodal relapse and 15 a systemic failure. At 3 years, local control rate was 87.8%, cancer-specific survival 72.5%, overall survival 57.1%, with 8 out of 20 non-cancer related deaths. In multivariate analysis, tumour volume was associated with a better outcome. In our series, SBRT was well tolerated and confirmed its efficacy, with local control and survival rates globally superior to those reported using conventional radiotherapy. A longer follow-up is needed in order to establish a correct comparison with surgical series, and to fully ascertain a potential negative impact of SBRT on comorbidities of such a fragile patients population.

Stereotactic body radiation therapy for lung metastases

INTRODUCTION Stereotactic body radiation therapy (SBRT) has an emerging role in patients affected with pulmonary metastases. Purpose of this study was to evaluate efficacy and tolerability of SBRT in a cohort of patients treated between 2003 and 2009 at our institution. METHODS A total of 61 patients with oligometastatic lung tumors (single pulmonary nodules in 73.7%) were included in the study. SBRT was performed with a stereotactic body frame and a 3D-conformal technique. Fifty-one patients received 26 Gy in 1 fraction, 22 a dose of 45 Gy in 3 fractions and 3 a dose of 36 Gy in 4 fractions. Primary tumor was lung cancer in 45.7% of patients, colorectal cancer in 21.3% and a variety of other origins in 33%. The primary endpoint was local control, secondary endpoints were survival and toxicity. RESULTS After a median follow-up interval of 20.4 months, local control rates at 2 and 3 years were 89% and 83.5%, overall survival 66.5% and 52.5%, cancer-specific survival 75.4% and 67%, progression-free survival 32.4% and 22.3%. Tumor volume was significantly associated to survival, with highest rates in patients with single small tumors. Median survival time was 42.8 months, while median progression-free survival time was 11.9 months. Toxicity profiles were good, with just one case of grade III toxicity (pneumonitis). CONCLUSION This study shows that SBRT is an effective and safe local treatment option for patients with lung metastases. Definitive results are strictly correlated to clinical selection of patients.

Patterns of care and survival in a retrospective analysis of 1059 patients with glioblastoma multiforme treated between 2002 and 2007: a multicenter study by the Central Nervous System Study Group of Airo (italian Association of Radiation Oncology).

OBJECTIVETo investigate the pattern of care and outcomes for newly diagnosed glioblastoma in Italy and compare our results with the previous Italian Patterns of Care study to determine whether significant changes occurred in clinical practice during the past 10 years. METHODSClinical, pathological, therapeutic, and survival data regarding 1059 patients treated in 18 radiotherapy centers between 2002 and 2007 were collected and retrospectively reviewed. RESULTSMost patients underwent both computed tomography and magnetic resonance imaging either preoperatively (62.7%) or postoperatively (35.5%). Only 123 patients (11.6%) underwent a biopsy. Radiochemotherapy with temozolomide was the most frequent adjuvant treatment (70.7%). Most patients (88.2%) received 3-dimensional conformal radiotherapy. Median survival was 9.5 months. Two- and 5-year survival rates were 24.8% and 3.9%, respectively. Multivariate analysis showed the statistical significance of age, postoperative Karnofsky Performance Status scale score, surgical extent, use of 3-dimensional conformal radiotherapy, and use of chemotherapy. Use of a more aggressive approach was associated with longer survival in elderly patients. Comparing our results with those of the subgroup of patients included in our previous study who were treated between 1997 and 2001, relevant differences were found: more frequent use of magnetic resonance imaging, surgical removal more common than biopsy, and widespread use of 3-dimensional conformal radiotherapy + temozolomide. Furthermore, a significant improvement in terms of survival was noted (P < .001). CONCLUSIONChanges in the care of glioblastoma over the past few years are documented. Prognosis of glioblastoma patients has slightly but significantly improved with a small but noteworthy number of relatively long-term survivors.

Dosimetric predictors of radiation-induced lung injury in stereotactic body radiation therapy

Materials and methods. The aim was to retrospectively investigate correlations between potential predictive parameters and the occurrence of radiation-induced lung injury in patients with primary or secondary lung tumours treated with stereotactic body radiation therapy (SBRT). Sixty patients (63 tumours) underwent SBRT, with a dose of 45 Gy in 3 fractions over 5 days or 26 Gy in single fraction. The following parameters were tested for correlation with Radiation Therapy Oncology Group (RTOG) lung toxicity score: planning target volume (PTV), tumour location, primary vs. metastatic tumour, and Mean Lung Dose (in 2 Gy fractions, MLD2). Normal Tissue Complication Probability (NTCP) values were then estimated. Results. The median follow-up time was 30.9 months (range 6.7–56.7). RTOG grade 0–1 toxicity was observed in 54/63 (85.7%) and grade 2–3 in 9/63 (14.3%) cases. Mean values of MLD2 for RTOG grade 0–1 and 2–3 were respectively 11.2 Gy (95% Confidence Interval (CI) 10.1–12.3 Gy) and 20.3 Gy (95% CI 16.6–23.9 Gy). NTCP mean values for RTOG grade 0–1 and 2–3 were respectively 4% (95% CI 2–5.9%) and 37% (95% CI 11.6–62.3%). Univariate analysis, performed with t-Student test, showed a statistically significant difference between MLD2 values in the two groups (t = 5.93 and p ≤ 0.001). Logistic regression analysis showed a good correlation between MLD2 and toxicity scores 2–3 (p = 0.008, odds ratio 1.5). From logistic regression relationship between the observed rates of grade 2–3 and MLD2, a D50=19.8 Gy and a γ50=2.2 were obtained. From the sigmoid-shaped dose-response relationship between NTCP and MLD2, a D50=22.4 Gy and γ50=2.2 were derived. Discussion. MLD2 is strongly associated to the risk of lung injury. Higher NTCP values are associated with a higher risk, but when comparing the expected to the observed toxicity rate, NTCP seems to underestimate the risk.

Seizure control following radiotherapy in patients with diffuse gliomas: a retrospective study

BACKGROUND Little information is available regarding the effect of conventional radiotherapy on glioma-related seizures. METHODS In this retrospective study, we analyzed the seizure response and outcome following conventional radiotherapy in a cohort of 43 patients with glioma (33 grade II, 10 grade III) and medically intractable epilepsy. RESULTS At 3 months after radiotherapy, seizure reduction was significant (≥ 50% reduction of frequency compared with baseline) in 31/43 patients (72%) of the whole series and in 25/33 patients (76%) with grade II gliomas, whereas at 12 months seizure reduction was significant in 26/34 (76%) and in 19/25 (76%) patients, respectively. Seizure reduction was observed more often among patients displaying an objective tumor response on MRI, but patients with no change on MRI also had a significant seizure reduction. Seizure freedom (Engel class I) was achieved at 12 months in 32% of all patients and in 38% of patients with grade II tumors. Timing of radiotherapy and duration of seizures prior to radiotherapy were significantly associated with seizure reduction. CONCLUSIONS This study showed that a high proportion of patients with medically intractable epilepsy from diffuse gliomas derive a significant and durable benefit from radiotherapy in terms of epilepsy control and that this positive effect is not strictly associated with tumor shrinkage as shown on MRI. Radiotherapy at tumor progression seems as effective as early radiotherapy after surgery. Prospective studies must confirm and better characterize the response to radiotherapy.

Radiotherapy and temozolomide in anaplastic astrocytoma: a retrospective multicenter study by the Central Nervous System Study Group of AIRO (Italian Association of Radiation Oncology).

Although the evidence for the benefit of adding temozolomide (TMZ) to radiotherapy (RT) is limited to glioblastoma patients, there is currently a trend toward treating anaplastic astrocytomas (AAs) with combined RT + TMZ. The aim of the present study was to describe the patterns of care of patients affected by AA and, particularly, to compare the outcome of patients treated exclusively with RT with those treated with RT + TMZ. Data of 295 newly diagnosed AAs treated with postoperative RT ± TMZ in the period from 2002 to 2007 were reviewed. More than 75% of patients underwent a surgical removal. All the patients had postoperative RT; 86.1% of them were treated with 3D-conformal RT (3D-CRT). Sixty-seven percent of the entire group received postoperative chemotherapy with TMZ (n = 198). One-hundred sixty-six patients received both concomitant and sequential TMZ. Prescription of postoperative TMZ increased in the most recent period (2005-2007). One- and 4-year survival rates were 70.2% and 28.6%, respectively. No statistically significant improvement in survival was observed with the addition of TMZ to RT (P = .59). Multivariate analysis showed the statistical significance of age, presence of seizures, Recursive Partitioning Analysis classes I-III, extent of surgical removal, and 3D-CRT. Changes in the care of AA over the past years are documented. Currently there is not evidence to justify the addition of TMZ to postoperative RT for patients with newly diagnosed AA outside a clinical trial. Results of prospective and randomized trials are needed.

Comparison of Gafchromic EBT2 and EBT3 for patient‐specific quality assurance: Cranial stereotactic radiosurgery using volumetric modulated arc therapy with multiple noncoplanar arcs

PURPOSE Patient-specific quality assurance in volumetric modulated arc therapy (VMAT) brain stereotactic radiosurgery raises specific issues on dosimetric procedures, mainly represented by the small radiation fields associated with the lack of lateral electronic equilibrium, the need of small detectors and the high dose delivered (up to 30 Gy). GafchromicTM EBT2 and EBT3 films may be considered the dosimeter of choice, and the authors here provide some additional data about uniformity correction for this new generation of radiochromic films. METHODS A new analysis method using blue channel for marker dye correction was proposed for uniformity correction both for EBT2 and EBT3 films. Symmetry, flatness, and field-width of a reference field were analyzed to provide an evaluation in a high-spatial resolution of the film uniformity for EBT3. Absolute doses were compared with thermoluminescent dosimeters (TLD) as baseline. VMAT plans with multiple noncoplanar arcs were generated with a treatment planning system on a selected pool of eleven patients with cranial lesions and then recalculated on a water-equivalent plastic phantom by Monte Carlo algorithm for patient-specific QA. 2D quantitative dose comparison parameters were calculated, for the computed and measured dose distributions, and tested for statistically significant differences. RESULTS Sensitometric curves showed a different behavior above dose of 5 Gy for EBT2 and EBT3 films; with the use of inhouse marker-dye correction method, the authors obtained values of 2.5% for flatness, 1.5% of symmetry, and a field width of 4.8 cm for a 5×5 cm2 reference field. Compared with TLD and selecting a 5% dose tolerance, the percentage of points with ICRU index below 1 was 100% for EBT2 and 83% for EBT3. Patients analysis revealed statistically significant differences (p<0.05) between EBT2 and EBT3 in the percentage of points with gamma values<1 (p=0.009 and p=0.016); the percent difference as well as the mean difference between calculated and measured isodoses (20% and 80%) were found not to be significant (p=0.074, p=0.185, and p=0.57). CONCLUSIONS Excellent performances in terms of dose homogeneity were obtained using a new blue channel method for marker-dye correction on both EBT2 and EBT3 GafchromicTM films. In comparison with TLD, the passing rates for the EBT2 film were higher than for EBT3; a good agreement with estimated data by Monte Carlo algorithm was found for both films, with some statistically significant differences again in favor of EBT2. These results suggest that the use of GafchromicTM EBT2 and EBT3 films is appropriate for dose verification measurements in VMAT stereotactic radiosurgery; taking into account the uncertainty associated with Gafchromic film dosimetry, the use of adequate action levels is strongly advised, in particular, for EBT3.

Postoperative Radiotherapy for Patients With Completely Resected Pathologic N2 Non-Small- Cell Lung Cancer: A Retrospective Analysis

BACKGROUND Adjuvant radiotherapy in non-small-cell lung cancer (NSCLC) is still controversial. The purpose of this retrospective study was to evaluate the role of postoperative radiotherapy (PORT) in terms of local control and survival in pathologic N2 NSCLC. PATIENTS AND METHODS From January 2003 to December 2008, 66 patients with pathologic N2 NSCLC received PORT. Mediastinal lymph node metastases were classified into single (12 patients) or multiple (54 patients) stations. All patients received conformal radiation therapy, with a median total dose of 50.4 Gy. Target volumes included the bronchial stump, ipsilateral hilum, all pathologically involved lymph node regions, and all the lymph nodes between 2 noncontiguous pathologic nodal stations. The pattern of failure was considered as locoregional or systemic, or a combination of both. Locoregional failure was defined as in field or out of field. RESULTS Median follow-up time was 34.9 months (range 3.5-62.8 months). Local control was 80% at 12 months, 77.2% at both 24 and 36 months, and 72.1% at 60 months. The pattern of failure was locoregional in 3 patients (1 out of field and 2 in field) and systemic in 25 patients, with 12 patients presenting both locoregional and distant disease. Overall survival at 12, 36, and 60 months was 77%, 44%, and 37%, respectively. Median survival time was 34 months. The number of pathologically involved lymph node stations was a prognostic factor for local control (P = .05), cancer-specific survival (CSS) (P = .04), and disease-free survival (DFS) (P = .04). CONCLUSION Despite the limitations of the present study, mainly represented by its retrospective nature, our data support the role of PORT in terms of locoregional control and overall survival benefit; the number of involved mediastinal lymph nodes represents a significant prognostic factor in patients with pathologic N2 NSCLC.

Radiotherapy in Italy for non-small cell lung cancer: patterns of care survey

AIMS AND BACKGROUND Surveys in clinical practice are useful to find how current clinical approaches follow recommendations from evidence-based medicine, to stimulate discussion in a multidisciplinary team, and to hypothesize collaborative multicentric trials. To assess management strategies for the use of radiotherapy in the treatment of lung cancer in Italy, in 2009, the Italian Society of Radiation Oncology Lung Cancer Study Group proposed the survey to all Italian radiation oncology institutions. Results were compared with literature data and international reports. STUDY DESIGN Questionnaires on patterns of care of non-small cell lung cancer were sent to radiation oncology centers active at June 2009 and evaluated data recorded in 2008. RESULTS A total of 65 of 143 Italian centers responded to the questionnaire. The responding centers reflect the distribution of radiotherapy centers throughout the country. Of the treated patients, 55.2% were stage III, and most cases had a good performance status. FDG-PET was routinely used by 51% of centers for diagnostic and contouring phases. Postoperative radiotherapy was prescribed to pN1 and pN2 patients in 42.2% and 98.5%, respectively. The possible use of neo-adjuvant concomitant chemoradiation was declared by 70% of responders. A sequential chemoradiation approach was actually used in 43.6% of cases, induction chemotherapy followed by concomitant radiochemotherapy in 42.4%, and upfront concomitant radiochemotherapy in only 14%. In 53% of the institutions, patients have a clinical examination by a radiation oncologist only after the beginning of chemotherapy and in 82.4% of cases they have already received 2-4 cycles of chemotherapy. Most of the institutions exclude elective nodal irradiation from routine application. Total dose and fractionation in adjuvant, neoadjuvant, curative and palliative settings confirm literature data. There were significant differences in treatment planning constraints applied for lung, esophageal and cardiac tissues. Of the responding centers, 41% had stereotactic therapy for primary inoperable lung cancer and for metastatic lesions. CONCLUSIONS In Italy, daily practice differs in some ways from the evidence supported by the results of meta-analyses/clinical trials as regards concurrent chemoradiation approaches. It could be postulated that there is an urgent need for groups that collaborate with the other societies involved in the treatment of non-small cell lung cancer in order to offer the best therapy to our patients.

CAVEOLIN-1 expression in brain metastasis from lung cancer predicts worse outcome and radioresistance, irrespective of tumor histotype

Brain metastases develop in one-third of patients with non-small-cell lung cancer and are associated with a dismal prognosis, irrespective of surgery or chemo-radiotherapy. Pathological markers for predicting outcomes after surgical resection and radiotherapy responsiveness are still lacking. Caveolin 1 has been associated with chemo- and radioresistance in various tumors, including non-small-cell lung cancer. Here, caveolin 1 expression was assessed in a series of 69 brain metastases from non-small-cell lung cancer and matched primary tumors to determine its role in predicting survival and radiotherapy responsiveness. Only caveolin 1 expression in brain metastasis was associated with poor prognosis and an increased risk of death (log rank test, p = 0.015). Moreover, in the younger patients (median age of <54 years), caveolin 1 expression neutralized the favorable effect of young age on survival compared with the older patients. Among the radiotherapy-treated patients, an increased risk of death was detected in the group with caveolin 1-positive brain metastasis (14 out of 22 patients, HR=6.839, 95% CI 1.849 to 25.301, Wald test p = 0.004). Overall, caveolin 1 expression in brain metastasis from non-small-cell lung cancer is independently predictive of worse outcome and radioresistance and could become an additional tool for personalized therapy in the critical subset of brain-metastatic non-small-cell lung cancer patients.