Influence of fraction size, total dose, and overall time on local control of T1–T2 glottic carcinoma

The authors review the main contributions of international literature to show the current status in clinical trials on unconventional fractionations of the dose in radiotherapy of head and neck cancers. Several clinical (but only a few randomized) trials have been conducted over the last 15 years using hyperfractionated (HF), accelerated (AF) or mixed (HF-AF) schedules. HF schedules have obtained promising results in terms of local control in comparison with conventional fractionation (CF) of the dose. Improvement in survival was also obtained by the random trials of Pinto and Sanchiz, whereas in EORTC trial no. 22791, the improvement in survival rate was only marginal. A significant increase in local control and, less frequently, in survival has been claimed in several studies using HF-AF. Such data still need to be confirmed by a random study, since EORTC trial 22811 showed superimposable results in comparison with CF. Selection of the most suitable cases for altered fractionation schemes is also being studied in ongoing trials of the EORTC (22851) and RTOG (90-03). As regards acute reactions during and after altered fractionation, they are more severe than after CF. Only pure HF with a dose intensity approximately comparable to CF seems to produce similar acute reactions. Several factors have been found to influence the severity of acute mucosal reactions: interfraction interval, overall treatment time, total dose, and field size. As regards late damage, genuine HF schemes seem to cause roughly equivalent late damage in comparison to CF, whereas high-dose intensity schedules have a higher rate of complications. Interfraction interval, overall treatment time, total dose, fraction size and field size can influence the risk of late sequelae. Before altered fractionations can be considered standard therapy, more data are needed, which should be provided by multicentric randomized trials, some of which are already in progress.

Download Full-text

Short Course Radiotherapy Concomitant with Temozolomide in GBM Patients: A Phase II Study

Tumori Journal ◽

10.5301/tj.5000672 ◽

2017 ◽

Vol 103 (5) ◽

pp. 457-463 ◽

Cited By ~ 3

Author(s):

Laura Fariselli ◽

Lucia Cuppini ◽

Paola Gaviani ◽

Marcello Marchetti ◽

Valentina Pinzi ◽

...

Keyword(s):

Total Dose ◽

Phase Ii ◽

Local Control ◽

Primary Endpoint ◽

Phase Ii Study ◽

Treatment Schedule ◽

Open Label ◽

Macdonald Criteria ◽

Secondary Endpoints ◽

Group B

Purpose Despite recent advances, the prognosis of glioblastoma (GBM) remains poor. The aim of this study was to assess the efficacy and tolerability of multiple daily fraction radiotherapy performed with multiple temozolomide (TMZ) administrations in newly diagnosed patients with GBM. Methods This trial was a prospective, open-label, monocentric, nonrandomized, single arm, phase II study. The primary endpoint was the proportion of progression-free patients at 12 months, and the secondary endpoints were overall survival (OS) and toxicity. Thirty-five patients underwent two radiotherapy courses concomitant with TMZ after surgery. At each course, radiation was delivered 3 times daily, 2 Gy/fraction, for 5 consecutive days, and the total dose was 60 Gy; concurrent TMZ was administered in a total dose of 150-200 mg/m2/day. Results The primary endpoint failed to be applied; Macdonald criteria could be used in 16 (46%) patients with local or intracerebral recurrence (group A). In 12 patients, due to suspicion of radiation necrosis vs recurrence, Macdonald criteria were not applied (group B). The OS was 22 months, and OS probabilities at 12, 18, and 24 months were 82%, 59%, and 44%, respectively. Hematologic toxicities generally did not exceed grade 2. The quality of life and cognitive functioning did not significantly change between baseline and the first follow-up. In the multivariate analysis, necrosis and pseudoprogression were significant prognostic factors of OS. Conclusions To improve local control and OS, a more aggressive treatment schedule should be explored. The related higher necrosis risk and its implications regarding local control deserve further investigation.

Download Full-text

Stereotactic hypofractionated high-dose irradiation (STI) for stage I non-small cell lung cancer (NSCLC): Mature results in 300 cases of a Japanese multi-institutional study

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.7045 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 7045-7045 ◽

Cited By ~ 1

Author(s):

H. Onishi ◽

Y. Nagata ◽

H. Shirato ◽

K. Karasawa ◽

K. Gomi ◽

...

Keyword(s):

Total Dose ◽

Local Control ◽

Survival Rates ◽

Progression Free Survival ◽

Pulmonary Complications ◽

Stage I ◽

High Dose ◽

Stage Ib ◽

Local Progression ◽

Stage Ia

7045 Background: With the increasing accuracy of localization for tumor-bearing areas using various new techniques, hypofractionated or single high-dose stereotactic irradiation (STI) has been actively investigated for stage I NSCLC in Japan. The current study retrospectively evaluated Japanese multi-institutional results for high-dose STI for stage I NSCLC. Methods: From 1993 to 2003, stereotactic three-dimensional treatment was performed using 3–10 non-coplanar dynamic arcs or 6–20 static ports for a total of 300 stage I (median age, 75 years; T1N0M0, n = 193; T2N0M0, n = 107) patients with primary NSCLC (adenocarcinoma, n = 138; squamous cell carcinoma, n = 129; and others, n = 33) in 14 institutions. Totally 190 patients were medically inoperable, and other 110 were medically operable but selected STI. A total dose of 18–75 Gy at the isocenter was administered in 1–22 fractions. Median calculated biological effective dose (BED) was 108 Gy (range, 57–180 Gy). Results: Median follow-up period of survivors was 38 months (range; 2–128 months). Pulmonary complications of NCI-CTC criteria (version 2.0) grade ≥ 3 were noted in 9 patients (3.0%). Local progression occurred in 44 patients (14.7%), and 5-year local control rate was high (86%) for BED ≥100 Gy (n = 227) compared to 67% for <100 Gy (n = 73) (P < 0.001). Overall 5-year survival rates of operable and inoperable patients were 65% and 37%, respectively. Overall 5-year survival rates in operable cases was high (74%) for BED ≥100 Gy (n = 85) compared to 37% for <100 Gy (n = 24) (P < 0.01). In a subset of operable patients irradiated with BED ≥100, 3-year locally progression-free survival rates was high (81%) for stage IA (n = 60) compared to 67% for stage IB (n = 23) (P < 0.05) Conclusions: Local control and survival rates of STI for stage I NSCLC are better with BED ≥100 Gy compared to <100 Gy. Survival rates in selected patients (medically operable, BED ≥100 Gy) were excellent, and potentially comparable to those of surgery. Stage IB patients displayed higher rate of local progression than stage IA. We have started multi-institutional prospective study for stage IA NSCLC with a schedule of total dose of 48 Gy in 4 fractions during 4–8 days. No significant financial relationships to disclose.

Download Full-text

The relationship between total dose, number of fractions and fraction size in the response of malignant melanoma in patients

British Journal of Radiology ◽

10.1259/0007-1285-51-611-905 ◽

1978 ◽

Vol 51 (611) ◽

pp. 905-909 ◽

Cited By ~ 129

Author(s):

Shirley Hornsey

Keyword(s):

Malignant Melanoma ◽

Total Dose ◽

Fraction Size ◽

Dose Number ◽

The Relationship

Download Full-text