A phase II study of cetuximab (C225) in combination with chemoradiation (CRT) in patients (pts) with stage III A/B non-small cell lung cancer (NSCLC): An interim report of the RTOG 0324 trial

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Background: Cetuximab (C225) is a chimerized monoclonal antibody that targets the epidermal growth factor receptor (EGFR). NSCLC commonly expresses the EGFR, which is associated with aggressive tumor behavior and poor clinical outcome. Preclinical model systems demonstrate radiosensitization following molecular inhibition of EGFR signaling. Methods: We report a phase II trial testing the combination of C225 with CRT in unresectable stage III NSCLC with a planned sample size of 84 PTS. Eligibility criteria included Zubrod performance status (PS) = 1, weight loss = 5% over past 3 months, FEV1 = 1.2 l, adequate hematologic, hepatic, and renal function. PTS received an initial dose of C225 (400 mg/m2) on day 1 of week 1, then weekly doses of C225 (250 mg/m2) until completion of therapy (weeks 2 –17). During week 2, patients started CRT (63 Gy/35 fractions) with weekly carboplatin (C) AUC 2 and paclitaxel (P) 45 mg/m2 × 6 doses followed by C (AUC 6) and P (200 mg/m2) × 2 cycles (weeks 12–17). Interim monitoring for severe (grade = 3) or excessive non-hematologic toxicities occurred after pts had been treated and followed for at least 90 days after RT. Primary endpoints include safety and compliance of concurrent C225 and CRT. Results: 93 pts were enrolled with 87 evaluable pts. Pts characteristics: 57% male, median age 64 years (range 42–85), 47% PS 0, 46% stage IIIA. Median follow-up is 14 months. Response rate is 62% (n=54) and 12 month overall survival (OS) is 68% (# at risk=56). Adverse events related to treatment include 20% (n=17) of pts with grade 4 hematologic toxicities and 7 pts who had grade 3 esophagitis. There was 1 infection related death, 1 death NOS, and 3 pts who died of pulmonary complications (adult respiratory distress syndrome, pneumonitis, and hypoxia). Conclusions: The combination of C225 with CRT is feasible. Further study will be needed to determine whether the addition C225 to CRT enhances toxicity or efficacy. Complete compliance and toxicity data along with 18 month OS will be reported.

No significant financial relationships to disclose.

Toxicities in a phase II study of accelerated high dose thoracic radiation therapy (TRT) with concurrent chemotherapy for limited small cell lung cancer (LSCLC) (RTOG 0239)

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Background: Accelerated fractionation proved beneficial in INT0096, but the total dose was low and local recurrence was high with higher acute grade (Gr.) 3+ esophagitis. RTOG 0239 was a phase II trial to improve local control and survival with LSCLC with acceptable acute Gr. 3+ esophagitis using accelerated high dose TRT and concurrent cisplatin/etoposide. This is the first report of acute Gr.3+ esophagitis and Gr.5 toxicities. Methods: Patients (pts) with LSCLC without pleural effusion, contralateral hilar or contralateral supraclavicular nodes and PS 0–1 were enrolled. TRT was given to large fields to 28.8 Gy at 1.8 Gy per fraction, 5 days per week for 16 fractions followed by BID with large field in AM, boost in PM, then off-cord boost BID for last 5 days, all at 1.8 Gy per fx for a total dose of 61.2 Gy in 34 fx in 5 weeks. Concurrent chemotherapy was started with TRT with cisplatin, 60 mg/m2 i.v. day 1; etoposide, 120 mg/m2 i.v. day 1; etoposide, 240 mg/m2 p.o. per day or 120 mg/m2 i.v. per day on days 2 or 3. Cycles were repeated q.3 wks during and for 2 cycles after TRT. Pts who have achieved complete response one month after completion of 4 cycles of chemotherapy were asked to participate in a prophylactic cranial irradiation (PCI) study. Common toxicity criteria (CTC) 2.0 was used for acute toxicity. Results: From 10/2003 to 5/2006, 72 pts were accrued. Median age was 63 yrs with 52% females. Survival data is still maturing. Acute toxicity information is available for 68 pts. Eleven pts (16%) experienced acute Gr. 3 and 1 pt (1%) had acute Gr. 4 esophagitis. 47 pts (69%) had grade 4 blood/bone marrow toxicities. There were 2 (3%) Gr. 5 toxicities reported [1 infection with neutropenia; 1 pulmonary (pneumonia)]. Conclusions: This accelerated high dose TRT with concurrent chemotherapy for LSCLC resulted in 17% acute Gr.3+ esophagitis compared to 27% with BID TRT with 45Gy in 3 weeks by INT0096. There were 3% grade 5 toxicities. This preliminary report suggests that RTOG-0239 has tolerable toxicity. The acute Gr3+ esophageal toxicity correlated with V20 and V40 will be presented. Pts continue to be followed for the primary endpoint of 2-year survival.

No significant financial relationships to disclose.

Patterns of practice in radiation therapy for non-small cell lung cancer among members of American Society of Therapeutic Radiology and Oncology

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Purpose: To investigate the dominant pattern of current practice in radiation therapy (RT) for lung cancer among members of American Society of Therapeutic Radiology and Oncology (ASTRO). Methods: A 35-item survey was designed by a panel of 8 board certified radiation oncologists regarding RT for lung cancer. Surveys were sent through email to 3,800 radiation oncologist members on September 10, 2006, with the results collected online on December 10, 2006. Here we report results on radiation decisions for non-small cell lung cancer (NSCLC). Results: The response rate was 19% (n = 727). The respondents saw an average of 8 consults (ranged 1–25) monthly during the survey time (summing up to a total of >60,000 new cases yearly). For stage I peripherally located NSCLC, 33%, 10% and 20% of respondents reported conventional fractionated, hypofractioned and stereotactic RT, respectively. Another 25% of respondents would have offered stereotactic RT if this technique were available at their center. For stage I centrally located tumors, 78% of respondents did not agree with, but 10% selected, stereotactic RT. For stage II and III, 76% of respondents selected 60–70 Gy in 1.8–2 Gy with chemotherapy. With regard to the combined modality approach for stage II and III disease, 76–77% of respondents selected concurrent chemoRT followed by adjuvant chemotherapy, and 11–16% sequential followed by concurrent chemoRT for patients with good performance status. For stage IV NSCLC with remarkable local disease, the consideration of RT ranged from 0 Gy, 3 Gyx10, 3 Gyx15, 2.5 Gyx20, to 2 Gyx30 in 27%, 17%, 8%, 13%, and 21% of respondents, respectively. Conclusions: The dominant pattern of practice for stage II/III disease is concurrent chemoRT, consistent with results of phase III trials. The treatment decisions for stage I and IV disease are diverse, partially due to technology advancement and the lack of large phase III trials.

No significant financial relationships to disclose.

Randomized trial of amifostine in locally advanced non-small cell lung cancer (NSCLC) patients receiving chemotherapy and hyperfractionated radiation (HRT): Long-term survival results of Radiation Therapy Oncology Group (RTOG) 9801

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Purpose: This analysis was conducted to address the potential antitumor effect of amifostine (AM) in NSCLC patients enrolled on RTOG-9801. The long-term survival results of RTOG-9801 are presented here. Methods: 243 patients (pts) with stage II/IIIAB NSCLC received induction paclitaxel (P) 225 mg/m2IV days 1, 22 and carboplatin (C) AUC 6 days 1, 22 and then concurrent weekly P (50 mg/m2) and C (AUC 2) and HRT (69.6 Gy at 1.2 Gy BID). Pts were randomly assigned to AM 500 mg IV 4x/week or no-AM during chemoradiation. Treatment differences for overall and disease-free survival (OS & DFS) were analyzed with the log-rank test; Gray's test was used for time to progression (TTP). Results: 118 pts were randomly assigned to receive AM and 121 to no-AM (4 pts were ineligible). The median follow-up for pts still alive is 52.3 months (mo) for the AM-arm and 58.3 mo for the no-AM arm (16.6 vs 17.9 for all pts). There are no significant differences in OS, DFS or TTP between arms. The median survival, 3-yr, and 5-yr OS are 17.1 mo, 27% and 17% (AM-arm) vs 18.4 mo, 28% and 16% (no-AM arm) (p=0.97). Grade 3/4/5 late-RT toxicities are similar (11%/3%/2% AM-arm vs 14%/4%/2% no-AM arm). Conclusion: While an earlier publication reported that amifostine did not reduce objective measures of severe esophagitis in RTOG-9801, patient-reported outcome analyses suggested a possible advantage to AM with decreased pain and swallowing symptoms (J Clin Oncol 23:2145–2154, 2005). This long-term follow-up analysis on survival shows no evidence of tumor radioprotection due to amifostine. The promising 5-yr OS suggests that induction paclitaxel/carboplatin (P/C) followed by concurrent RT and weekly low-dose P/C is comparable to other regimens using cisplatin doublets at higher dosages every 3–4 weeks. Research supported by NCI and Medimmune Oncology.

No significant financial relationships to disclose.

Oncolytic adenovirus expressing apoptotic genes targets radiation resistant (RR) esophageal cancer

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Background: Only 25% of esophageal cancer patients achieve pathological complete response after standard chemoradiotherapy. Radiation dose escalation is associated with higher toxicity but no therapeutic improvement. In addition, esophageal cancer cells may develop radiation resistance (RR) after fractionated radiation exposure. Therefore, molecular targeting therapy for RR esophageal cancer is urgently needed. Methods: Six pairs of RR esophageal cancer cell lines were established by applying continuous 2 Gy fractionated irradiation. Ad/TRAIL-E1, an oncolytic adenoviral vector expressing both apoptotic TRAIL and viral E1A genes under the control of tumor specific human telomerase reverse transcriptase promoter, was constructed. Phosphate buffer solution and vectors expressing the TRAIL gene only, the GFP marker protein only, or the E1A gene only served as controls. Trans-gene expression, apoptosis activation, and the RR esophageal cancer cells targeted were evaluated in vitro and in vivo. A human esophageal RR cancer model was established and locally treated with Ad/TRAIL-E1 or controls. Results: After fractionated radiation exposure, esophageal cancer cell lines developed RR (up to 25-fold) that was associated with activation of the anti-apoptotic pathway. Ad/TRAIL-E1 activated an apoptotic cascade of caspases and selectively killed esophageal cancer cells but not normal cells. Ad/TRAIL-E1 preferentially targeted RR stem-like cancer cells with higher trans-gene expression and cell killing compared with parental cells. Overexpression (3 times) of Coxsackie's and adenoviral receptors in RR esophageal cancer cells compared with parental cells was noted. Ad/TRAIL-E1 therapy resulted in 40% tumor-free survival without the treatment- related toxicity found in human RR esophageal adenocarcinoma mouse models (p<0.05 as compared with controls). Conclusions: Esophageal cancer cells develop RR after fractionated radiation exposure. Ad/TRAIL-E1 preferentially targeted RR stem-like esophageal cancer cells, which resulted in a 40% cure rate.

No significant financial relationships to disclose.

A phase III study of Æ-941 with induction chemotherapy (IC) and concomitant chemoradiotherapy (CRT) for stage III non- small cell lung cancer (NSCLC) (NCI T99–0046, RTOG 02–70, MDA 99–303)

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Background: Æ-941 is a shark cartilage extract with antiangiogenic properties. We conducted a placebo-controlled trial testing Æ-941, with IC and CRT, in unresectable stage III NSCLC. Methods: Eligibility criteria included performance status (PS) < 2, weight loss < 10%. Subjects received one of two treatment regimens depending on site of enrollment: carboplatin (C) (AUC 6) and paclitaxel (P) (200 mg/m2) × 2 cycles followed by CRT (60 Gy/30 fractions) with weekly C (AUC 2) and P (45 mg/m2) × 6 doses or cisplatin (CDDP) (75 mg/m2, d1) and vinorelbine (V) (30 mg/m2, d1 and 8) × 2 cycles followed by CRT (60 Gy/30 fractions) with CDDP (75 mg/m2, day 1) and V (15 mg/m2, d1 and 8) × 2 cycles. Subjects were randomized to receive Æ-941 (Arm A) or placebo (Arm B), 120 mL orally twice daily, at the start of IC and continuing after CRT as maintenance therapy. Randomization was stratified for stage, gender, and type of chemotherapy. The primary endpoint was overall survival (OS), with a planned sample size of 756 subjects providing 80% power to detect a 25% difference in OS, assuming a control arm median survival time (MST) of 13 months, type I error 0.05. Results: Between 6/00 and 2/06, 384 subjects were enrolled onto the trial and randomized. In 2/06 the trial was closed to new patient entry due to insufficient accrual. This final analysis is based on 379 randomized and eligible subjects (188 arm A, 191 arm B). Subject characteristics: 60% male, median age 63 years (range 37–84), 56% stage IIIB, 58% C-based chemotherapy, median follow-up 3.7 years. There was no significant difference in OS between arms A and B, with MSTs of 14.4 (95% CI 12.6–17.9) and 15.6 (95% CI 13.8–18.1) months, respectively (log-rank p=0.73). OS by pre-specified stratification factors: stage IIIB vs IIIA (MST 13.9 vs. 17.4 months, p=0.25), C vs. CDDP chemotherapy (MST 14.4 vs. 16.7 months, p=0.13), and male vs. female (MST 15.7 vs. 15.1 months, p=0.74). The study drug was well tolerated. Fewer subjects in arm A experienced grade 3 or higher adverse events (66% vs. 77%, p=0.018). Conclusions: The addition of Æ−941 to IC and CRT does not improve OS in patients with unresectable stage III NSCLC.

No significant financial relationships to disclose.