Contribution of image-guided adaptive brachytherapy to pelvic nodes treatment in locally advanced cervical cancer.
With the increasing use of simultaneous integrated boost in the treatment of cervical cancer, there is a need to anticipate the brachytherapy (BT) contribution at the level of the pathologic pelvic lymph nodes. This study aimed to report the dose delivered at their level during BT.



Patients with pelvic nodal involvement and treated with a combination of chemoradiation followed by image-guided adaptive pulsed-dose-rate BT were selected. On per BT three-dimensional images, pelvic lymphadenopathies were delineated, without planning aim. For the purposes of the study, D100, D98, D90, and D50were reviewed and converted in 2-Gy equivalent doses, using the linear quadratic model with an α/β of 10 Gy.



Ninety-one patients were identified, allowing evaluation at the level of 226 lymphadenopathies. The majority of them were external iliac (48%), followed by common iliac (25%), and internal iliac (16%) regions. The 2-Gy equivalent doses D98were 4.4 ± 1.9 Gy, 5.4 ± 3.1 Gy, and 4.3 ± 2.1 Gy for the obturator, internal iliac, and external iliac, respectively, and 2.8 ± 2.5 Gy for the common iliac. The contribution to the common iliac nodes was significantly lower than the one of external and internal iliac (p < 0.001).



BT significantly contributes to the treatment of pelvic nodes at the level of approximately 5 Gy in the internal, external, and obturator areas and 2.5 Gy in the common iliac, allowing the anticipation of nodal boost with the simultaneous integrated boost technique. However, important individual variations have been observed, and evaluation of the genuine BT contribution should be recommended.
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France; Department of Radiation Oncology, Benavides Cancer Institute, University of Santo Tomas Hospital, Manila, Philippines. Electronic address: WARREN.BACORRO@gustaveroussy.fr.
Warren
W
Bacorro
Department of Medical Physics, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Isabelle
I
Dumas
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Antonin
A
Levy
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Eleonor
E
Rivin Del Campo
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Charles-Henri
CH
Canova
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Tony
T
Felefly
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Andres
A
Huertas
Department of Medical Physics, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Fanny
F
Marsolat
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Christine
C
Haie-Meder
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France; Institut de Recherche Biomédicale des Armées, Bretigny-sur-Orge, France; French Military Health Academy, Ecole du Val-de-Grâce, Paris, France.
Cyrus
C
Chargari
Department of Radiation Oncology, Brachytherapy Unit, Gustave Roussy, University of Paris Saclay, Villejuif, France.
Renaud
R
Mazeron
D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D059248:Chemoradiotherapy; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D010388:Pelvis; D011879:Radiotherapy Dosage; D018714:Radiotherapy, Adjuvant; D061089:Radiotherapy, Image-Guided; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*
Cervix cancer; Dose; Image-guided adaptive brachytherapy; Node; Simultaneous integrated boost