TY - JOUR
T1 - Locally advanced cervical cancer
T2 - Is it relevant to report image-guided adaptive brachytherapy using point A dose?
AU - Mazeron, Renaud
AU - Gouy, Sebastien
AU - Escande, Alexandre
AU - Dumas, Isabelle
AU - Rivin del Campo, Eleonor
AU - Bentivegna, Enrica
AU - Bacorro, Warren
AU - Lefkopoulos, Dimitri
AU - Deutsch, Eric
AU - Morice, Philippe
AU - Haie-Meder, Christine
AU - Chargari, Cyrus
N1 - Publisher Copyright:
© 2017 American Brachytherapy Society
PY - 2017/7/1
Y1 - 2017/7/1
N2 - Purpose To evaluate the usefulness of reporting the point A dose in patients with locally advanced cervical cancer treated with image-guided adaptive brachytherapy (IGABT). Methods and Materials Dosimetric data from patients treated with a combination of chemoradiation and intracavitary IGABT were examined in light of their outcomes. Prescribing followed the Groupe Européen de Curiethérapie–European Society for Radiation Oncology recommendations. All doses were converted in 2-Gy equivalent. The relationships between the D90 high-risk clinical target volume (CTVHR) and intermediate-risk clinical target volume (CTVIR) and point A doses were studied. Dose-effect relationships based on the probit model and log-rank test were assessed. Results Two hundred twelve patients were included with a median followup of 53.0 months. A total of 28 local relapses were reported, resulting in a local control rate of 86.6% at 3 years. Mean D90 CTVHR, CTVIR, and point A doses were: 79.7 ± 10.4 Gy, 67.4 ± 5.8 Gy, and 66.4 ± 5.6 Gy, respectively. The mean D90 were significantly different and independent from the mean point A dose, even in bulky tumors at diagnosis or in large CTVHR lesions. Point A dose appeared correlated with TRAK, and finally with the D90 CTVHR through a complex formula including the CTVHR volume (R2 = 0.55). Whereas significant relationships between the probability of achieving local control and the D90 CTVHR and CTVIR (p = 0.08 and 0.025) were observed, no similar relationship was found with point A dose except a trend of an inverse relation. After sorting patients according to three dose levels, highest local control rates were observed in patients with D90 CTVHR ≥85 Gy, whereas those with point A doses ≥70 Gy had the worst outcomes. Conclusions In patients treated with IGABT, point A dose is not predictive of local control but a surrogate of the irradiated volume. Its relationships with the D90 CTVHR are indirect and complex rising the question of relevance of its reporting in routine.
AB - Purpose To evaluate the usefulness of reporting the point A dose in patients with locally advanced cervical cancer treated with image-guided adaptive brachytherapy (IGABT). Methods and Materials Dosimetric data from patients treated with a combination of chemoradiation and intracavitary IGABT were examined in light of their outcomes. Prescribing followed the Groupe Européen de Curiethérapie–European Society for Radiation Oncology recommendations. All doses were converted in 2-Gy equivalent. The relationships between the D90 high-risk clinical target volume (CTVHR) and intermediate-risk clinical target volume (CTVIR) and point A doses were studied. Dose-effect relationships based on the probit model and log-rank test were assessed. Results Two hundred twelve patients were included with a median followup of 53.0 months. A total of 28 local relapses were reported, resulting in a local control rate of 86.6% at 3 years. Mean D90 CTVHR, CTVIR, and point A doses were: 79.7 ± 10.4 Gy, 67.4 ± 5.8 Gy, and 66.4 ± 5.6 Gy, respectively. The mean D90 were significantly different and independent from the mean point A dose, even in bulky tumors at diagnosis or in large CTVHR lesions. Point A dose appeared correlated with TRAK, and finally with the D90 CTVHR through a complex formula including the CTVHR volume (R2 = 0.55). Whereas significant relationships between the probability of achieving local control and the D90 CTVHR and CTVIR (p = 0.08 and 0.025) were observed, no similar relationship was found with point A dose except a trend of an inverse relation. After sorting patients according to three dose levels, highest local control rates were observed in patients with D90 CTVHR ≥85 Gy, whereas those with point A doses ≥70 Gy had the worst outcomes. Conclusions In patients treated with IGABT, point A dose is not predictive of local control but a surrogate of the irradiated volume. Its relationships with the D90 CTVHR are indirect and complex rising the question of relevance of its reporting in routine.
KW - High-risk clinical target volume
KW - Image-guided adaptive brachytherapy
KW - Point A
KW - Tumor control probability
UR - http://www.scopus.com/inward/record.url?scp=85019551570&partnerID=8YFLogxK
U2 - 10.1016/j.brachy.2017.04.244
DO - 10.1016/j.brachy.2017.04.244
M3 - Article
C2 - 28551312
AN - SCOPUS:85019551570
SN - 1538-4721
VL - 16
SP - 862
EP - 869
JO - Brachytherapy
JF - Brachytherapy
IS - 4
ER -