From conventionally fractionated radiation therapy to hyperfractionated radiation therapy alone and with concurrent chemotherapy in patients with early‐stage nonsmall cell lung cancer

Abstract

2 ). Biologically equivalent doses for the 3 groups were 72 Gy, 78 Gy, and 76 Gy, respectively, for acute effects (a/b 5 10 Gy) and 120 Gy, 111 Gy, and 111 Gy, respectively, for late effects (a/b 5 2 Gy). RESULTS.For all 250 patients, the overall median survival was 27 months, the cause-specific survival was 27 months, the local progression-free survival was 32 months, and distant metastasis-free survival was not achieved; and the respective 5-year survival rates were 27%, 32%, 45%, and 68%. CF achieved significantly inferior survival than either HFX RT alone or HFX RT-Pac/C (P 5 .0332 and P 5 .0013, respectively), and no difference was observed between the 2 HFX RT regimens (P 5 .1934). Only acute hematologic high-grade toxicity (grade 3) was more frequent with HFX RT-Pac/C than with either RT alone, whereas other toxicities were similar between the 3 treatment groups.CONCLUSIONS. HFX RT with or without concurrent chemotherapy may be better than CF in patients with early-stage NSCLC. The role of chemotherapy deserves further investigation, because the group that received chemotherapy in the current study had a higher incidence of acute high-grade hematologic toxicity.

Cell division cycle 25 homolog c effects on low-dose hyper-radiosensitivity and induced radioresistance at elevated dosage in A549 cells

“…The potential for hyperfractionation to improve the therapeutic ratio of radiation treatments for NSCLC was recognized through failure of large-dose fractionation to improve local control and the observation that smaller fractions were associated with fewer effects in normal tissues [31]. Understanding the mechanism of HRS/IRR in lung cancer cells can aid in the optimization of the therapeutic ratio, allowing successful treatment with smaller dose fractions.…”

Nontraditional radiotherapy regimens for non-small-cell lung cancer

“…СОД может быть увеличена, если интервал времени между фракциями составляет 5-6 ч. Таким образом, использование данных режимов позволяет сочетать увеличенное воздействие на раковые клетки с сокращением риска развития поздних лучевых осложнений. Экспериментальными и клиническими исследованиями показано, что использование режимов гиперфракционирования позволяет безопасно увеличивать дозы ЛТ на 20-30% [21].…”

“…В качестве дальнейшей перспективы улучшения результатов авторы предполагают комбинирование режимов гиперфракционирования с химиотерапией. Результаты одного из исследовательских центров подтвердили, что режим гиперфракционирования хорошо переносится: медиана и 5-летняя выживаемость составляют 29 мес и 29% соответственно, демонстрируя значительное улучшение по сравнению с историческим контролем при обычной СОД 60 Гр в конвенциональном режиме [21].…”