Frequency of use and outcome of surgical resection in the management of malignant mesothelioma in a community-based population: Results in 5,937 patients

7510

Background: Multimodality therapy of mesothelioma patients treated at specialized tertiary hospitals report surgical resection rates of 42% (Flores RM et al. Prognostic Factors in the Treatment of Malignant Pleural Mesothelioma at a Large Tertiary Referral Center. J Thorac Oncol 2007;2(10):957–965.). Treatment strategies in the community are less well defined and surgical expertise is not readily available. We undertook this study to evaluate the rate of surgical resection and its association with survival in a non-tertiary based population. Methods: The Surveillance, Epidemiology, and End Results (SEER) database was searched from 1990 - 2004. Variables analyzed included age, sex, race, year of diagnosis, laterality, vital status, stage, surgery, and reasons for no surgery. The association of resection on overall survival was estimated by the Kaplan-Meier method and examined in a Cox proportional hazards model adjusting for covariates. Results: Pathologically proven malignant pleural mesothelioma was identified in 5,937 patients: 1,166 women, 4,771 men; median age was 70 years. Surgical resection rate was 11% (n=636). Univariate analysis demonstrated a median survival of 13 months with surgical resection and a median survival of 7 months in the non-resected group (p<0.0001). Multivariate analysis demonstrated improved survival for surgically resected patients (HR 0.7, p<0.0001), controlling for age, gender, and stage. Conclusions: Surgical resection was associated with improved survival when controlling for age, stage, and gender. However, the rate of surgical resection was much lower in the community when compared to tertiary referral centers. Treatment efforts should be focused on a multidisciplinary approach which includes surgical evaluation.

No significant financial relationships to disclose.

Prognostic factors in the treatment of malignant pleural mesothelioma at a large tertiary referral center

INTRODUCTION

Most studies describing the natural history and prognostic factors for malignant pleural mesothelioma antedate accurate pathologic diagnosis, staging by computed tomography, and a universal staging system. We conducted a large single-institution analysis to identify prognostic factors and assess the association of resection with outcome in a contemporary patient population.

METHODS

Patients with biopsy-proven malignant pleural mesothelioma at our institution were identified and clinical data were obtained from an institutional database. Survival and prognostic factors were analyzed by the Kaplan-Meier method, log-rank test, and Cox proportional hazards analysis. A p value <0.05 was considered statistically significant.

RESULTS

From 1990 to 2005, 945 patients were identified: 755 men, 190 women; median age, 66 years (range, 26-93). Extrapleural pneumonectomy was performed in 208 (22%), pleurectomy/decortication in 176 (19%). Operative mortality was 4% (16/384). Multimodality therapy including surgery was associated with a median survival of 20.1 months. Significant predictors of overall survival included histology, gender, smoking, asbestos exposure, laterality, surgical resection by extrapleural pneumonectomy or pleurectomy/decortication, American Joint Committee on Cancer stage, and symptoms. A Cox model demonstrated a hazard ratio of 1.4 without surgical resection when controlling for histology, stage, gender, asbestos exposure, smoking history, symptoms, and laterality (p = 0.003).

CONCLUSIONS

In addition to tumor histology and pathologic stage, predictors of survival include gender, asbestos exposure, smoking, symptoms, laterality, and clinical stage. Surgical resection in a multimodality setting was associated with improved survival.

Single agent bevacizumab and bevacizumab in combination with docetaxel and cisplatin as induction therapy for resectable IB-IIIA non-small cell lung cancer

18045

Background: Bevacizumab (Bev) improves response and survival in patients with advanced non-squamous lung cancer with chemotherapy however there are limited data as single agent therapy and in early stage NSCLC. Methods: Patients with resectable stage IB-IIIA NSCLC were eligible. Patients with adenocarcinoma (Cohort 1) received preoperative Bev and docetaxel and cisplatin (DC). Patients with squamous histology, central location or recent hemoptysis received DC induction therapy without Bev (Cohort 2). Cohort 1 received Bev (15 mg/kg) followed by CT 2 weeks later to assess single agent Bev response. Subsequently D (75 mg/m2) and C (75 mg/m2) were given q 3 weeks; an additional 2 cycles of Bev was administered with C2 and C3 of DC (total of 3 preoperative doses of Bev). Cohort 2 received DC alone followed by resection. Both cohorts received adjuvant Bev x 1 year. Study endpoints included response to single agent Bev, downstaging, safety and survival. Results: 19 patients of planned 70 were enrolled (11 Cohort 1 and 8 Cohort 2). On Cohort 1, there were 2 clinical stage IIB and 9 IIIA patients. After single agent Bev (by bimensional measurement), > 10% reduction in tumor size was observed after 2 weeks in 6/11 patients (- 20%, 15%, 16%, 15%, 13% and 20%). After Bev + DC, there were 6/10 (60%) PRs and DC delivery was 96%. 6/10 patient underwent R0 resection; 1 R2 and 2 were unresectable. 1 patient developed hemoptysis preoperatively and 1 patient developed an upper GI bleed post-operatively. There were otherwise no Bev related operative complications observed. 5/9 patients were downstaged by induction treatment. 3 patients received adjuvant bevacizumab to date (median 5.7 cycles). 8 patients were treated on Cohort 2 (3 with stage IB, 1 with IIB and 4 with IIIA). All 8 patients underwent R0 resection. DC delivery was 94% and there were 6/8 PRs. Downstaging was observed in 5/8 patients and 6/8 are receiving adjuvant Bev (median # cycles to date = 6.7). Conclusions: Bev as a single agent demonstrates regression of tumors after 2 weeks. To date, Bev has been safely administered in the neoadjuvant and adjuvant setting. Preoperative chemotherapy is well tolerated with more than 90% full dose drug delivery. The study is ongoing. Supported by Genentech, Inc.

[Table: see text]

Phase I study of the antifolate pralatrexate given with vitamin B12 and folic acid supplementation in patients (pts) with advanced non-small cell lung cancer (NSCLC)

13006

Background: Pralatrexate is a novel antifolate that has shown promising activity in the treatment of pts with previously- treated NSCLC at doses of 135–150 mg/m2 IV every other week (q2w). [Krug, Clin Cancer Res 9(6), 2003; 6(9), 2000] The addition of vitamin B12 and folic acid supplementation may mitigate toxicity from pralatrexate and improve efficacy by allowing higher doses to be delivered. Methods: This study is designed to determine the maximum tolerated dose (MTD) of pralatrexate in combination with vitamin B12 and folic acid supplementation in pts with NSCLC. Key eligibility criteria include confirmed stage IIIB or IV NSCLC; at least 1 prior chemotherapy regimen; Karnofsky performance status (KPS) = 70%; and no other active concurrent malignancy. Using a rapid escalation design, pralatrexate was initially administered at a dose of 150 mg/m2 IV q2w, escalating by 40 mg/m2 increments in successive cohorts, with one patient per cohort if no dose limiting toxicity (DLT) is encountered. All pts receive vitamin B12 1 mg intramuscular q 8–10 weeks and folic acid 1 mg by mouth once a day beginning at least 7 days prior to pralatrexate. All patients undergo pharmacokinetic testing following their first and second dose of pralatrexate. Results: Between 1/05–12/06, a total of 9 pts have been treated at the following dose levels: 150 (n=1), 190 (n=1), 230 (n=1), and 270 (n=6). Patient characteristics include: 2 male/7 female; median age 63 (range 52–73); KPS 80–90%; all pts had stage 4 NSCLC; 5 pts received 1 prior regimen and 4 pts received 2 or more prior regimens. Grade 3 esophagitis was a DLT in one patient at the 270 mg/m2 dose. Three other patients experienced grade 1–2 mucositis at this dose level without limiting drug delivery. The trial is ongoing, and enrollment is planned at 310 mg/m2 q2w to determine the MTD. Conclusions: When given in combination with vitamin B12 and folic acid supplementation, pralatrexate has been well tolerated in this pt population, with an MTD at least twice as high as achieved in previous phase 1 testing without supplementation. We plan to conduct a phase 2 trial of pralatrexate with vitamin B12 and folic acid supplementation to see if a higher dose will improve efficacy.

No significant financial relationships to disclose.

Efficacy of a comfrey root (Symphyti offic. radix) extract ointment in the treatment of patients with painful osteoarthritis of the knee: results of a double-blind, randomised, bicenter, placebo-controlled trial

This randomised, double-blind, bicenter, placebo-controlled clinical trial investigated the effect of a daily application of 6g Kytta-Salbe f (3 x 2 g) over a 3 week period with patients suffering from painful osteoarthritis of the knee. The two hundred and twenty patients examined consisted of 153 women and 67 men of an average age of 57.9 years. On average, the complaints relating to osteoarthritis of the knee had persisted for 6.5 years. Two hundred and twenty patients were included in the Full Analysis Set (FAS) and safety collective, 186 (84.5%) in the Valid Case Analysis Set (VCAS) collective. In the course of the trial, the visual analog scale (VAS) total score (primary target value) in the verum group dropped by 51.6 mm (54.7%) and in the placebo group by 10.1 mm (10.7%). The average difference between the groups of 41.5 mm (95% confidence interval=34.8 to 48.2 mm) or 44.0% is significant (p<0.001). The significance is confirmed through the evaluation of the diary, the VCAS evaluation and the separate assessment of the two centres. This also applies to the separate assessment of the VAS total score following pain at rest and on movement. The WOMAC (Western Ontario and McMaster Universities) total score (secondary target value) also improved similar to the VAS total score. At the end of the trial, a reduction by 60.4 mm (58.0%) was recorded for the verum group and a reduction of 14.7 mm (14.1%) for the placebo group. The average group difference of 45.7 mm (95% confidence interval=37.1 to 54.3 mm) or 43.9% is significant (p<0.001). The difference between the treatment groups increased systematically and significantly, in parallel with the duration of the treatment. Thus, the superiority of the treatment with Kytta-Salbe f over that with the placebo is proven, even by means of the multi-factorial multivariate analysis for repetitive measurements. In respect of the explorative secondary target values SF-36 (quality of life), angle measurement (mobility of the knee), CGI (clinical global impression) and global assessment of efficacy by the physician and the patient, a significant superiority (p<0.001 each) of the verum group over the placebo group was also proven. The results suggest that the comfrey root extract ointment is well suited for the treatment of osteoarthritis of the knee. Pain is reduced, mobility of the knee improved and quality of life increased.

Global Gene Expression Profiling of Pleural Mesotheliomas: Overexpression of Aurora Kinases and P16/CDKN2A Deletion as Prognostic Factors and Critical Evaluation of Microarray-Based Prognostic Prediction

Most gene expression profiling studies of mesothelioma have been based on relatively small sample numbers, limiting their statistical power. We did Affymetrix U133A microarray analysis on 99 pleural mesotheliomas, in which multivariate analysis showed advanced-stage, sarcomatous histology and P16/CDKN2A homozygous deletion to be significant independent adverse prognostic factors. Comparison of the expression profiles of epithelioid versus sarcomatous mesotheliomas identified many genes significantly overexpressed among the former, including previously unrecognized ones, such as uroplakins and kallikrein 11, both confirmed by immunohistochemistry. Examination of the gene expression correlates of survival showed that more aggressive mesotheliomas expressed higher levels of Aurora kinases A and B and functionally related genes involved in mitosis and cell cycle control. Independent confirmation of the negative effect of Aurora kinase B was obtained by immunohistochemistry in a separate patient cohort. A role for Aurora kinases in the aggressive behavior of mesotheliomas is of potential clinical interest because of the recent development of small-molecule inhibitors. We then used our data to develop microarray-based predictors of 1 year survival; these achieved a maximal accuracy of 68% in cross-validation. However, this was inferior to prognostic prediction based on standard clinicopathologic variables and P16/CDNK2A status (accuracy, 73%), and adding the microarray model to the latter did not improve overall accuracy. Finally, we evaluated three recently published microarray-based outcome prediction models, but their accuracies ranged from 63% to 67%, consistently lower than reported. Gene expression profiling of mesotheliomas is an important discovery tool, but its power in clinical prognostication has been overestimated.

Hemithoracic radiation therapy after pleurectomy/decortication for malignant pleural mesothelioma

PURPOSE

To evaluate pleurectomy/decortication (P/D) and adjuvant radiotherapy (RT) in the treatment of malignant pleural mesothelioma (MPM).

METHODS AND MATERIALS

In a retrospective review, we included MPM patients treated with P/D and adjuvant RT at Memorial Sloan-Kettering Cancer Center from 1974 to 2003. When indicated, patients received intraoperative brachytherapy to residual tumor.

RESULTS

All 123 patients received external beam RT (median dose, 42.5 Gy; range, 7.2-67.8 Gy) to the ipsilateral hemithorax postoperatively. Fifty-four patients underwent brachytherapy (matched peripheral dose, 160 Gy). The median and 2-year overall survival for all patients was 13.5 months (range, 1-199 months) and 23%, respectively. One-year actuarial local control for all patients was 42%. Multivariate analysis for overall survival revealed radiation dose <40 Gy (p = 0.001), nonepithelioid histology (p = 0.002), left-sided disease (p = 0.01), and the use of an implant (p = 0.02) to be unfavorable. Two patients (1.6%) died from Grade 5 toxicity within 1 month of treatment.

CONCLUSIONS

Pleurectomy/decortication with adjuvant radiotherapy is not an effective treatment option for patients with MPM. Our results imply that residual disease cannot be eradicated with external RT with or without brachytherapy and that a more extensive surgery followed by external RT might be required to improve local control and overall survival.