Ovarian Transposition Strategy in Patients with Cervical Cancer Who Undergo Pelvic Radiation: Proposal of Ovarian Placement Based on Virtual Simulations

Objective: To establish a proposal for the location for ovarian transposition, considering different irradiation techniques and time to ovarian failure. Methods: Patients with cervical cancer in childbearing age submitted to adjuvant radiotherapy were selected. Delineation of simulated positions of the ovaries and pelvic radiation planning was done in CT, with three techniques: 3D conformal radiotherapy, intensity-modulated radiotherapy, and volumetric modulated arc radiotherapy. In order to correlate the ovaries maximal doses with the time to ovarian failure, the authors have used the one adaptation of Wallace model that predicts oocytes survival rates after radiation exposure. Results: Thirteen patients who were being treated between 2008 and 2017 were studied. When the ovaries were positioned 10 cm cranially from the sacral promontory, the pelvic radiation entails a decrease of 20% in the time to ovarian failure compared with that expected for a female at the same age without irradiation exposition. The placement of the ovaries <5 cm cranially from the sacral promontory results in a decrease >90%. There was no difference in time to ovarian failure between the radiation treatment techniques tested: 3D conformal radiotherapy, intensity-modulated radiotherapy, and volumetric modulated arc radiotherapy (p=0.197). Conclusions: The present study, based on virtual simulations, is the first to use the sacral promontory as a reference for a proposal of ovarian location with transposition. The authors have correlated the position of the ovaries and percentage of decrease in time to ovarian failure. These findings can potentially improve the management and counselling of patients with cervical cancer in childbearing age and deserve clinical validation.

Quality of Automated Stereotactic Radiosurgery Plans in Patients with 4 to 10 Brain Metastases

The purpose was to compare linac-based stereotactic radiosurgery and hypofractionated radiotherapy plan quality of automated planning, intensity modulated radiotherapy (IMRT) and manual dynamic conformal arc (DCA) plans as well as single- and multiple-isocenter techniques for multiple brain metastases (BM). For twelve patients with four to ten BM, seven non-coplanar linac-based plans were created: a manually planned DCA plan with a separate isocenter for each metastasis, a single-isocenter dynamic IMRT plan, an automatically generated single-isocenter volumetric modulated arc radiotherapy (VMAT) plan, four automatically generated single-isocenter DCA plans with three or five couch angles, with high or low sparing of normal tissue. Paddick conformity index, gradient index (GI), mean dose, total V12Gy and V5Gy of uninvolved brain, number of monitor units (MUs), irradiation time and pass rate were compared. The GI was significantly higher for VMAT than for separate-isocenter, IMRT, and all automatically generated plans. The number of MUs was lowest for VMAT, followed by automatically generated DCA and IMRT plans and highest for manual DCA plans. Irradiation time was the shortest for automatically planned DCA plans. Automatically generated linac-based single-isocenter plans for multiple BM reduce the number of MUs and irradiation time with at least comparable GI and V5Gy relative to the reference separate-isocenter DCA plans.

Hypofractionated Volumetric-Modulated Arc Radiotherapy for Patients With Non-Small-Cell Lung Cancer Not Suitable for Surgery or Conventional Chemoradiotherapy or SBRT

BackgroundHypofractionated radiotherapy (HypoRT) has been used to pursue an alternative treatment regimen for patients with non-small-cell lung cancer (NSCLC) who are not eligible for stereotactic ablative radiotherapy (SABR), surgery or concurrent chemoradiotherapy (CCRT) and has shown good local control and safety. We analyzed the feasibility of using volumetric-modulated arc radiotherapy (VMAT) with the simultaneous integrated boost (SIB) technique to achieve high local control with few treatment-related toxicities.Patients and MethodsA total of 55 patients with stage I-IV NSCLC who were not candidates for SABR, surgery or CCRT were included in the present study. All patients received a prescribed dose of 60 to 66 Gy in 15 fractions. Local progression-free survival (LPFS), PFS, overall survival (OS), and toxicities were retrospectively analyzed.ResultsThirty-three patients (60.0%) had stage IV or recurrent disease in this study. The median follow-up time was 8 months (interquartile range: 5.0-16.3 months). The 1-year and 2-year OS rates were 84.3% and 69.9%, and the 1-year and 2-year LPFS rates were 91.0% and 63.0%. The median OS (mOS) and median LPFS (mLPFS) were not reached, and median PFS (mPFS) was 15 months. Twenty-eight (51.9%) patients had disease progression at the time of analysis. Of these, 7 (13.0%), 7 (13.0%) and 21 (38.9%) had local recurrence, locoregional failure and distant metastasis, respectively. All cases of local recurrence were found within the SIB region. Four patients had grade 2-3 pneumonitis, and 8 patients had grade 2-3 esophagitis. Patients with grade 2-3 esophagitis had significantly higher maximum dose and dose to 5 cm3 volume to esophagus than those with grade 0-1 esophagitis. No grade 4 or higher toxicity was observed.ConclusionThe 60 to 66 Gy in 15 fractions RT regimen provides favorable local control and survival with well-tolerated toxicities. Hypofractionated VMAT+SIB is an alternative treatment option for patients with NSCLC who cannot tolerate standard definitive therapy.