Virtual Library
Start Your Search
B.C.J. Cho
Author of
-
+
MO14 - Mesothelioma II - Surgery and Multimodality (ID 121)
- Event: WCLC 2013
- Type: Mini Oral Abstract Session
- Track: Mesothelioma
- Presentations: 1
- Moderators:E. Lim, B. McCaughan
- Coordinates: 10/29/2013, 10:30 - 12:00, Bayside Gallery B, Level 1
-
+
MO14.09 - 5-year experience with accelerated induction hypofractionated hemithoracic intensity modulated radiation therapy (IMRT) followed by extrapleural pneumonectomy (EPP) for malignant pleural mesothelioma (MPM) (ID 2022)
10:30 - 12:00 | Author(s): B.C.J. Cho
- Abstract
- Presentation
Background
Our experience in tri-modality therapy for MPM with induction chemotherapy followed by EPP and high dose hemithoracic radiation demonstrated that completion of EPP and radiation provided the best results. We therefore developed a new protocol of accelerated induction hypofractionated hemithoracic IMRT followed by EPP to deliver optimal radiation to the whole tumor bed in a short period of time. EPP is performed approximately one week after completion of radiation to limit the risk of pneumonitis. The results of Surgery for Mesothelioma After Radiation Therapy (SMART) was reviewed and compared to our previous cohort of patients undergoing induction chemotherapy followed by EPP and adjuvant hemithoracic radiation.Methods
All patients undergoing EPP in our institution between 01/2001 and 06/2013 were reviewed. The SMART protocol (25 Gy in 5 daily fractions over 1 week delivered to the entire ipsilateral hemithorax by IMRT with concomitant boost of 5 Gy to volumes at high risk based on CT and PET scan findings) was started in 2008. EPP was performed 6±2 days after radiation therapy. The results of the SMART protocol were compared to the group of patients undergoing induction chemotherapy followed by EPP as part of a trimodality approach.Results
A total of 111 patients underwent EPP between 01/2001 and 06/2013 with a hospital mortality of 4.5% (n=5). A total of 64 patients (81% men, 59±9 years old, 81% with epithelial histologic subtype) underwent induction chemotherapy, while 39 (82% men, 62±9 years old, 69% with epithelial histologic subtype) underwent SMART. Seven patients had no induction therapy and one had pre-operative chemo- and radiation therapy. Since 2008, the number of surgical patients undergoing SMART progressively increased from 14% in 2008 to 100% in 2013. None of the patients undergoing SMART died in hospital or within 30 days of surgery, while 4 of the 64 patients (6.4%) undergoing induction chemotherapy died in hospital after EPP (p=0.1). Patients undergoing SMART tended to have a greater proportion of ypN2 disease on final pathology than patients completing induction chemotherapy before EPP (58% vs 41%, respectively; p=0.09). After a median follow-up of 16 months after the start of therapy, the 3-year survival was significantly better in patients with epithelial disease undergoing SMART (n=27) compared to patients with epithelial disease undergoing induction chemotherapy and EPP (n=52) (79% 3-year survival vs 30% 3-year survival, respectively; p=0.04). In contrast, the 3-year survival of patients with biphasic disease was similar between patients undergoing SMART (n=12) or induction chemotherapy and EPP (n=12) (20% vs 8%, respectively; p=0.8). Multivariate survival analysis using Cox regression model demonstrated that epithelial histologic subtype (p=0.0003), the absence of ypN2 disease (p=0.007) and SMART (p=0.03) were predictors of better survival.Conclusion
Over the past 5 years, accelerated hemithoracic IMRT followed by EPP has become our preferred approach for surgically resectable MPM. Surgery for mesothelioma after radiation therapy was feasible with no operative mortality in 39 patients. Although comparison with our historical cohort of patients has limitations, our current protocol provides very encouraging results in patients with epithelial disease with a 3 year survival of 79%.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
-
+
MO17 - Radiotherapy I: Stereotactic Ablative Body Radiotherapy (ID 106)
- Event: WCLC 2013
- Type: Mini Oral Abstract Session
- Track: Radiation Oncology + Radiotherapy
- Presentations: 1
- Moderators:M. Zwitter, S.K. Vinod
- Coordinates: 10/29/2013, 16:15 - 17:45, Bayside 204 A+B, Level 2
-
+
MO17.03 - Incidental Prophylactic Nodal Irradiation and Patterns of Nodal Relapse in Inoperable Early Stage NSCLC Patients Treated with SBRT: A Case-Matched Analysis (ID 2024)
16:15 - 17:45 | Author(s): B.C.J. Cho
- Abstract
- Presentation
Background
Reported non-small cell lung cancer (NSCLC) nodal failure rates following stereotactic body radiotherapy (SBRT) are lower than those reported in the surgical series when matched for stage. We hypothesize that this effect is due to incidental prophylactic nodal irradiation.Methods
A prospectively collected group of medically inoperable early stage NSCLC patients (n=179) from 2004 to 2010 was used to identify a patient cohort with nodal relapses (n=19). These cases were matched, 1:2, to controls, controlling for tumour volume (i.e. same or greater) and tumour location (i.e. same lobe). Reference (normalized total) point doses at the ipsilateral hilum and carina, demographic data, and clinical outcomes were extracted from the medical record. Multivariate logistical regression analyses determined variables of interest.Results
The case and control cohorts were well matched with respect to age, sex, method of nodal staging, SUVmax, histology subtype, dose and length of follow up.. The controls, as expected, had larger gross tumour volumes (p=0.02). The mean hilar doses were 9.6 and 22.4 Gy for cases and controls, respectively (p=0.014). Similarly, the mean carinal doses were 7.0 and 9.2 Gy, respectively (p=0.13). The mean ipsilateral hilar doses were 19.8 and 3.6 Gy for ipsilateral non-hilar and hilar nodal relapses, respectively (p=0.01). The conditional density plot appears to demonstrate an inverse dose-effect relationship between ipsilateral hilar normalized total dose and risk of ipsilateral hilar relapse (Figure 1).Figure 1Conclusion
Incidental hilar dose greater than 20 Gy (normalized to 2Gy/fraction) appears to be correlated with lack of hilar relapses in inoperable early stage NSCLC patients treated with SBRT.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
-
+
O10 - Stereotactic Ablative Body Radiotherapy (ID 104)
- Event: WCLC 2013
- Type: Oral Abstract Session
- Track: Radiation Oncology + Radiotherapy
- Presentations: 1
- Moderators:H. Onishi, J.Y. Chang
- Coordinates: 10/28/2013, 16:15 - 17:45, Parkside 110 A+B, Level 1
-
+
O10.06 - Inter-Rater Reliability of the Categorization of Late Radiographic Changes after Lung Stereotactic Body Radiation Therapy (SBRT) (ID 1901)
16:15 - 17:45 | Author(s): B.C.J. Cho
- Abstract
- Presentation
Background
Radiographic changes following lung SBRT have been previously categorized into 4 groups: modified conventional pattern (A), mass-like fibrosis (B), scar-like fibrosis (C) and no evidence of increased density (D) (Dahele et al.).The purpose of this study was to assess the inter-rater reliability of this categorization in patients with early stage non-small cell lung cancer.Methods
79 patients treated with SBRT for early stage NSCLC at a single institution who had a minimum follow-up of 6 months were included in this study. Serial post-treatment CT images were presented to expert clinicians (up to 6) familiar with post-SBRT radiographic changes and were scored by each individual in a blinded fashion according to the published categorization of A, B, C or D. The proportion of patients categorized as A, B, C or D at each interval was determined. Krippendorff's alpha (KA) was used to establish inter-rater reliability at each time point. A leave-one-out analysis was performed at each time point on each rater to determine the sensitivity of the KA score to an individual rater. To explore if a training effect existed the KA of the first and last 20 patients scored by the raters was determined.Results
There were 351 ratings on 67 patients at 12mo, 250 ratings on 49 patients at 24mo, 169ratings on 31 patients at 36mo and 80 ratings on 14 patients at 48mo. The proportion of patients scored in each category of A,B,C &D is reported in Table 1. Table 1: Scale Category by Time-Point
Category A was the most common at all time points except 48 months when category C was the most common. KA was 0.28, 0.27, 0.18 and 0.27 at 12, 24, 36 and 48 months respectively. The range of KA in the leave-one-out analysis was 0.25-0.31, 0.24-0.27, 0.15-0.22 and 0.24-0.31 at 12, 24, 36 and 48 months respectively. The KA of the first 20 patients vs the last 20 patients was 0.34 vs 0.47 at 12 months.A (Modified-Conventional) B (Mass-like Fibrosis) C (Scar-like Fibrosis) D (No Evidence of Increased Density) 6 months 43% 9% 6% 42% 12 months 50% 16% 11% 23% 18 months 46% 18% 16% 20% 24 months 46% 22% 17% 15% 36 months 40% 24% 21% 15% 48 months 29% 24% 31% 16% Conclusion
The predominant pattern of post SBRT radiographic changes evolves over time. In this study categorization of late post-SBRT radiographic changes has moderate inter-rater agreement. There is a suggestion of a training effect with more experience. However, categorization of late radiographic changes following SBRT is challenging and may require specific training.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
-
+
P1.08 - Poster Session 1 - Radiotherapy (ID 195)
- Event: WCLC 2013
- Type: Poster Session
- Track: Radiation Oncology + Radiotherapy
- Presentations: 1
- Moderators:
- Coordinates: 10/28/2013, 09:30 - 16:30, Exhibit Hall, Ground Level
-
+
P1.08-019 - Late Radiographic Changes After Lung Stereotactic Body Radiotherapy: Piloting a Recurrence Scale and a Synoptic Reporting Scale (ID 2209)
09:30 - 16:30 | Author(s): B.C.J. Cho
- Abstract
Background
Radiographic lung changes after Stereotactic Body Radiotherapy (SBRT) for non-small cell lung cancer (NSCLC) are difficult to interpret. The reliability of previous scoring systems and their relationship to local failure has not been assessed. The purpose of this study was to design a synoptic radiographic scale for characterizing late radiographic changes after SBRT and to determine the inter-rater reliability of the scale.Methods
A Recurrence Scale (RS) was developed among lung radiation oncology/SBRT experts at a single institution, and a Synoptic Radiographic Scale (SRS) was designed in collaboration with an expert thoracic radiologist. For the RS, the suspicion for local recurrence on CT images was scored on a 5 point scale: 1) complete response, no recurrence; 2) fibrosis, not suspicious for recurrence; 3) fibrosis/mass, indeterminate for recurrence; 4) fibrosis/mass, suspicious for recurrence and 5) biopsy proven recurrence. On the SRS, CT changes were scored as ‘increasing’, ‘stable’, ‘decreasing’, ‘no change’ or ‘obscured’, along five dimensions: changes in the primary tumor site, involved lobe, consolidation, ground-glass opacity, and volume loss. Early stage NSCLC patients treated with SBRT at the institution with a minimum follow-up of 6 months were included. Serial post-treatment CT images at 12, 18, 24, 36, and 48 months were presented to the expert group (up to 6) who scored both scales in a blinded fashion. Krippendorff's alpha (KA) was used to assess inter-rater reliability. The association between RS score and known local failure was compared using Fisher’s Exact Test. The association between ‘growing tumor’ on the SRS and known local failure was compared using Fisher’s Exact Test.Results
79 patients were scored; 7 of them had documented local failures. Experts did 11243 scorings in total, ranging from 2351 at 6 months to 480 at 48 months. For the RS, the KA was 0.27, 0.36, 0.23 and 0.45 at 12, 24, 36 and 48 months respectively. For the SRS, KA was 0.22, 0.14 and 0.11 for the treated tumor at 12, 24 and 48 months and 0.33, 0.36 and 0.22 for consolidation at 12, 24 and 36 months. The tumor was scored as obscured in 40% of patients by 24 months. Of patients with local failure, 71% were at least once scored as ‘suspicious for recurrence’ by at least one rater, compared to 28% in patients without failure (p = 0.03). 86% of patients with failure were scored at least once as increased opacity in tumor site by at least one of raters, compared to 35% in patients without failure (p = 0.01).Conclusion
The RS has a significant relationship with local failure, and there is fair inter-agreement among experts on the suspicion of recurrence following SBRT. The SRS has low inter-rater reliability. Among its categories, only an increase in the opacity of treated tumor site is significantly related to failure. With future refinement of SRS categories, it can be a useful tool to standardize post-SBRT radiology reporting.
-
+
P2.08 - Poster Session 2 - Radiotherapy (ID 198)
- Event: WCLC 2013
- Type: Poster Session
- Track: Radiation Oncology + Radiotherapy
- Presentations: 1
- Moderators:
- Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level
-
+
P2.08-004 - Impact of medical co-morbidities on survival in patients treated with stereotactic body radiotherapy for early stage non-small cell lung cancer (ID 827)
09:30 - 16:30 | Author(s): B.C.J. Cho
- Abstract
Background
Stereotactic body radiotherapy (SBRT) is an effective treatment for early stage inoperable non-small cell lung cancer (NSCLC), with loco-regional control of 80-90%. However, the median overall survival of these patients is limited. We evaluate the impact of co-morbidities on patient survival and whether a subset of patients who may not benefit from SBRT can be identified.Methods
Patients treated on a prospective protocol at a single cancer center with SBRT for T1-T2N0 NSCLC from Oct 2004-May 2012 were evaluated. The most common doses delivered were 48Gy/4fr and 54Gy/3fr. The presence of significant medical co-morbidities including cardiac disease, COPD, cerebro-vascular disease, diabetes, previous pneumonectomy and oxygen dependence were recorded at baseline. Patient, tumor, and treatment data as well as outcomes were prospectively collected. Log rank tests were performed for survival analysis and chi squared tests used to analyze deaths within 1 year from radiotherapy treatment (D<1y). Cancer specific deaths (CSD) were defined as any death following a recurrence of the previously treated NSCLC.Results
There were 279 patients identified, 134 female (48%) and 145 male (52%). The median age was 76 years (range 48-93). The performance status was ECOG 0 in 87 patients (31%), ECOG 1 in 127 patients (46%), ECOG 2 in 53 patients (19%) and ECOG 3 in 9 patients (3%). There were 212 (76%) with T1 tumors, the remainder (24%) T2 tumors. The median follow up was 1.3 years. At last follow up, 111 patients (40%) had died, including 42 (15%) patients with D<1y. Of all deaths, 25 (22.5%) were CSD, the remainder from other causes. There were 222 patients (80%) identified as having a significant co-morbidity, collectively these conditions did not influence deaths from any cause (DAC) or CSD. The presence of cardiac disease (N=67) led to an increased risk of DAC (HR 4.1, p = 0.04) but not CSD (HR 1.2, p=0.28). These results were more pronounced for D<1y, patients with cardiac disease having increased D<1y, (HR 7.34, p=0.007), but not CSD<1y, (HR 2.9, p=0.09). Other co-morbidities were not correlated of survival. ECOG status was correlated with both DAC (HR 15.1, p=0.005) and CSD (HR 9.3, p=0.05).Conclusion
The presence of respiratory and vascular co-morbidities should not necessarily preclude a patient from receiving SBRT. ECOG status and prognosis from a cardiac point of view may be associated with poorer overall survival at 1 year and should be considered when assessing a patient’s suitability for SBRT.
