miércoles, 29 de mayo de 2013

Phase 1 Study of Dose Escalation in Hypofractionated Proton Beam Therapy for Non-Small Cell Lung Cancer.

 2013 May 17. pii: S0360-3016(13)00359-3. doi: 10.1016/j.ijrobp.2013.03.035. 

Phase 1 Study of Dose Escalation in Hypofractionated Proton Beam Therapy for Non-Small Cell Lung Cancer.

Source

Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: dgomez@mdanderson.org.
Abstract

BACKGROUND:

Many patients with locally advanced non-small cell lung cancer (NSCLC) cannot undergo concurrent chemotherapy because of comorbidities or poor performance status. Hypofractionated radiation regimens, if tolerable, may provide an option to these patients for effective local control.

METHODS AND MATERIALS:

Twenty-five patients were enrolled in a phase 1 dose-escalation trial of proton beam therapy (PBT) from September 2010 through July 2012. Eligible patients had histologically documented lung cancer, thymic tumors, carcinoid tumors, or metastatic thyroid tumors. Concurrent chemotherapy was not allowed, but concurrent treatment with biologic agents was. The dose-escalation schema comprised 15 fractions of 3 Gy(relative biological effectiveness [RBE])/fraction, 3.5 Gy(RBE)/fraction, or 4 Gy(RBE)/fraction. Dose constraints were derived from biologically equivalent doses of standard fractionated treatment.

RESULTS:

The median follow-up time for patients alive at the time of analysis was 13 months (range, 8-28 months). Fifteen patients received treatment to hilar or mediastinal lymph nodes. Two patients experienced dose-limiting toxicity possibly related to treatment; 1 received 3.5-Gy(RBE) fractions and experienced an in-field tracheoesophageal fistula 9 months after PBT and 1 month after bevacizumab. The other patient received 4-Gy(RBE) fractions and was hospitalized for bacterial pneumonia/radiation pneumonitis 4 months after PBT.

CONCLUSION:

Hypofractionated PBT to the thorax delivered over 3 weeks was well tolerated even with significant doses to the lungs and mediastinal structures. Phase 2/3 trials are needed to compare the efficacy of this technique with standard treatment for locally advanced NSCLC.

viernes, 24 de mayo de 2013

¿Más es Mejor en Cáncer de Pulmón?

Standard-Dose Radiation Bests High-Dose Radiation in Advanced NSCLC


IMNG Medical Media, 2013 May 16, P Wendling

Standard-dose radiation produced better overall survival and locoregional control than did high-dose radiation when given with concurrent chemotherapy in patients with newly diagnosed stage III non–small cell lung cancer in the phase III, randomized RTOG 0617 trial.
Patients on the high dose had a 56% greater risk of death than those on a standard 60 Gy dose. Median overall survival times were 18.5 months with high-dose radiation and 28.7 months with a standard dose (hazard ratio, 1.56;P = .0007).
The risk of local failure also was increased by 37% in the high-dose arm (HR, 1.37; P = .03).
“At this point, there is no clear reason for the poor outcome we experienced on the high-dose arm,” lead author Dr. Jeffrey Bradley said in a press briefing highlighting studies to be presented at the upcoming annual meeting of the American Society of Clinical Oncology (ASCO).
The most likely culprit is unreported toxicities, although other possible explanations are increased heart dose, longer duration of therapy, or a combination of these factors, he said.
The results are surprising because conventional thinking has been that higher doses of radiation would more effectively kill the tumor and thereby improve survival.
A phase-III trial in the 1970s established the standard radiation dose of 60 Gy in this setting but, over time, several radiation dose-ranging phase-II studies have reported promising results and improved median survival times with radiation doses up to 74 Gy, explained Dr. Bradley, professor of radiation oncology and chief of the thoracic service at Washington University, St. Louis.
At the same time, improvements in technology such as three-dimensional radiation therapy (RT) and intensity-modulated RT techniques have made RT delivery more precise, allowing organs and tissues sensitive to radiation to receive less radiation while the tumor receives more. This technique was explored in Radiation Therapy Oncology Group (RTOG) 0617.
“This is a very surprising result, especially when using these special radiation techniques that were designed to be more precise, you would expect that the outcome would be better,” ASCO president Sandra Swain, medical director of the Washington (D.C.) Cancer Institute, told reporters. “This should really put an end to higher-dose treatments, given the better outcomes in the standard-dose arms.”
Dr. Bradley said, “A lot of phase-III trials turn out negative when phase-II trials look good, so I think it was good to do a phase-III trial and get this answered.”
RTOG 0617 randomly assigned 464 patients with newly diagnosed, unresected stage-III non–small cell lung cancer to conformal RT to 60 Gy, five times per week for 6 weeks or to 74 Gy five times per week for 7.5 weeks. All patients received concurrent chemotherapy with weekly paclitaxel (Taxol) and carboplatin, with a second randomization for patients to receive consolidation chemotherapy with or without cetuximab (Erbitux).
Among the 419 patients available for analysis at 18 months, local failure rates were 25% with standard-dose RT and 34.3% with high-dose RT (P = .03, as noted above), Dr. Bradley reported.
Median 18-month overall survival rates were 67% with the standard radiation dose vs. 54% with the high dose.
Median overall survival times in both groups were higher than expected, but “the overall survival benefit of 60 Gy is independent of the cetuximab question,” he said. Data from that portion of the trial are expected to be reported in 2014.
Finally, the only significant difference in physician-reported side effects was a slightly higher rate of esophagitis in the high-dose arms (21% vs. 7%).
Full details of RTOG 0617 (abstract 7501) will be reported 10:15 a.m. on June 4 at ASCO’s annual meeting in Chicago.
The study was supported by the National Cancer Institute. Dr. Bradley reported having no relevant financial disclosures. A coauthor reported research funding from the NCI.


sábado, 4 de mayo de 2013

A Phase 3 Trial of Whole Brain Radiation Therapy and Stereotactic Radiosurgery Alone Versus WBRT and SRS With Temozolomide or Erlotinib for Non-Small Cell Lung Cancer and 1 to 3 Brain Metastases: Radiation Therapy Oncology Group 0320


International Journal of Radiation Oncology-Biology-Physics
Volume 85, Issue 5, Pages A1-A18, e201-e248, 1151-1392 (1 April 2013)

Paul W. Sperduto, Meihua Wang, H. Ian Robins, Michael C. Schell, Maria Werner-Wasik, Ritsuko Komaki, Luis Souhami, Mark K. Buyyounouski, Deepak Khuntia, William Demas, Sunjay A. Shah, Lucien A. Nedzi, Gad Perry, John H. Suh, Minesh P. Mehta



Abstract

BackgroundA phase 3 Radiation Therapy Oncology Group (RTOG) study subset analysis demonstrated improved overall survival (OS) with the addition of stereotactic radiosurgery (SRS) to whole brain radiation therapy (WBRT) in non-small cell lung cancer (NSCLC) patients with 1 to 3 brain metastases. Because temozolomide (TMZ) and erlotinib (ETN) cross the blood-brain barrier and have documented activity in NSCLC, a phase 3 study was designed to test whether these drugs would improve the OS associated with WBRT + SRS.Methods and MaterialsNSCLC patients with 1 to 3 brain metastases were randomized to receive WBRT (2.5 Gy × 15 to 37.5 Gy) and SRS alone, versus WBRT + SRS + TMZ (75 mg/m2/day × 21 days) or ETN (150 mg/day). ETN (150 mg/day) or TMZ (150-200 mg/m2/day × 5 days/month) could be continued for as long as 6 months after WBRT + SRS. The primary endpoint was OS.ResultsAfter 126 patients were enrolled, the study closed because of accrual limitations. The median survival times (MST) for WBRT + SRS, WBRT + SRS + TMZ, and WBRT + SRS + ETN were qualitatively different (13.4, 6.3, and 6.1 months, respectively), although the differences were not statistically significant. Time to central nervous system progression and performance status at 6 months were better in the WBRT + SRS arm. Grade 3 to 5 toxicity was 11%, 41%, and 49% in arms 1, 2, and 3, respectively (P<.001).
Conclusion
The addition of TMZ or ETN to WBRT + SRS in NSCLC patients with 1 to 3 brain metastases did not improve survival and possibly had a deleterious effect. Because the analysis is underpowered, these data suggest but do not prove that increased toxicity was the cause of inferior survival in the drug arms.





ESFUERZO Y SUPERACION CONTRA EL CANCER: Body Transformation-Cancer to Bodybuilder


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