Stereotactic Body Reirradiation in Gynaecological Cancer: Outcomes and Toxicities from a Single Institution Experience

AIMS

To report toxicity profile, outcomes and quality of life (QoL) data in patients with recurrent gynaecological cancer who underwent stereotactic body radiotherapy (SBRT) retreatment.

MATERIALS AND METHODS

Data from patients' folders were retrospectively extracted, focusing on the primary neoplasm, previous systemic therapies and previous radiotherapy. Concerning SBRT, the total dose (five daily fractions) was delivered with a linear accelerator using intensity-modulated radiotherapy techniques. Acute and late toxicities were assessed by the CTCAE 4.03 scale. QoL was evaluated according to the Cancer Linear Analogue Scale [CLAS1 (fatigue), CLAS2 (energy level), CLAS3 (daily activities)].

RESULTS

Between December 2005 and August 2021, 23 patients (median age 71 years, range 48-80) with 27 lesions were treated. Most patients had endometrial (34.8%), ovarian (26.1%) and cervical cancer (26.1%) as the primary tumour. The most common SBRT schedules in five fractions were 30 Gy (33.3%), 35 Gy (29.6%) and 40 Gy (29.6%). The median follow-up was 32 months (range 3-128). There were no patients reporting acute or late toxicities higher than grade 2, except for a bone fracture. One- and 2-year local control was 77.9% and 70.8%, respectively. One- and 2-year overall survival was 82.6% and 75.1%, respectively. The overall response rate was 96.0%. Regarding QoL, no statistically significant difference was identified between the baseline and follow-up values: the median CLAS1, CLAS2 and CLAS3 scores for each category were 6 (range 4-10) at baseline and 6 (range 3-10) 1 month after SBRT.

CONCLUSIONS

This preliminary experience suggests that SBRT retreatment for recurrent gynaecological cancer is a highly feasible and safe treatment with limited side-effects and no short-term QoL impairment.

Volumetric Intensity-Modulated Arc Stereotactic Radiosurgery Boost in Oligometastatic Patients with Spine Metastases: a Dose-escalation Study

AIMS

To report the final results of a dose-escalation study of volumetric intensity-modulated arc stereotactic radiosurgery (VMAT-SRS) boost after three-dimensional conformal radiation therapy in patients with spine metastases.

MATERIALS AND METHODS

Oligometastatic cancer patients bearing up to five synchronous metastases (visceral or bone, including vertebral ones) and candidates for surgery or radiosurgery were considered for inclusion. 25 Gy was delivered in 10 daily fractions (2 weeks) to the metastatic lesion, affected vertebrae and adjacent ones (one cranial and one caudal vertebra). Sequentially, the dose to spinal metastases was progressively increased (8 Gy, 10 Gy, 12 Gy) in the patient cohorts. Dose-limiting toxicities were defined as any treatment-related non-hematologic acute adverse effects rated as grade ≥3 or any acute haematological toxicity rated as ≥ 4 by the Radiation Therapy Oncology Group scale.

RESULTS

Fifty-two lesions accounting for 40 consecutive patients (male/female: 29/11; median age: 71 years; range 40-85) were treated from April 2011 to September 2020. Most patients had a primary prostate (65.0%) or breast cancer (22.5%). Thirty-two patients received 8 Gy VMAT-SRS boost (total BED _α/β10: 45.6 Gy), 14 patients received 10 Gy (total BED _α/β10: 51.2 Gy) and six patients received 12 Gy (total BED _α/β10: 57.6 Gy). The median follow-up time was over 70 months (range 2-240 months). No acute toxicities > grade 2 and no late toxicities > grade 1 were recorded. The overall response rate based on computed tomography/positron emission tomography-computed tomography/magnetic resonance was 78.8%. The 24-month actuarial local control, distant metastases-free survival and overall survival rates were 88.5%, 27.1% and 90.3%, respectively.

CONCLUSION

A 12 Gy spine metastasis SRS boost following 25 Gy to the affected and adjacent vertebrae was feasible with an excellent local control rate and toxicity profile.

Stereotactic radiosurgery for bone metastases in oligometastatic prostate cancer patients: DESTROY-2 clinical trial subanalysis

INTRODUCTION

Aim of this analysis was to report toxicity and clinical outcomes in oligorecurrent prostate cancer (PCa) patients treated with single fraction stereotactic radiosurgery (SRS) for bone metastases.

METHODS

We separately analyzed clinical data of PCa patients with bone oligometastases enrolled in a prospective phase I trial (DESTROY-2). DESTROY-2 was based on SRS delivered using volumetric modulated arc therapy in patients with primary or metastatic tumors in several extra-cranial body sites. Acute and late toxicity, biochemical tumor response, local control (LC), distant metastases-free (DPFS), progression-free (PFS), time to next-line systemic treatment-free (NEST-FS), and overall survival (OS) were calculated.

RESULTS

Data on 37 PCa patients, carrying out 50 bone metastases, candidates for curative-intent treatment and treated with SRS at our Institution were collected. SRS dose ranged between 12 and 24 Gy. One grade 1 acute skin toxicity in one patient treated on the hip (24 Gy) and one grade 1 late skin toxicity in a patient with a scapular lesion (24 Gy) were recorded. No cases of bone fracture were registered in the treated population. With a median follow-up of 25 months (range 3-72 months) 2-year actuarial LC, DPFS, PFS, and OS were 96.7%, 58.1%, 58.1%, and 95.8%, respectively. Median and 2-year NEST-FS were 30 months (range 1-69 months) and 51.2%, respectively.

CONCLUSIONS

Data analysis showed few toxicity events, high local control rate and prolonged NEST-FS after linear accelerator-based radiosurgery of bone oligometastases from PCa. The possibility of postponing systemic treatments in patients with oligometastatic PCa by means of SRS should be taken into account. Further prospective studies on larger series are needed to confirm the reported results.