Radiothérapie stéréotaxique hypofractionnée des métastases osseuses

Stereotactic body radiation therapy for bone oligometastases

Stereotactic body radiation therapy is effective for the local management of oligometastases (at most five metastases) with a benefit in survival and local control. Most studies on the management of oligometastases focus on all oligometastatic sites in primary cancer and very few focus on a single oligometastatic site. In particular, there are few data on bone oligometastases, which represent one of the preferred sites for secondary cancer locations. This article focuses on the benefit of stereotactic radiotherapy for bone oligometastases of all cancers by histological types, and reviews the results of major studies in this field.

[Opioid prescriptions in bone metastatic cancer patients: A cross sectional nationwide pharmacoepidemiological study]

Oncological situations represent the majority of palliative situations. Labeling the palliative stage often comes too late in oncology. Pain comes first among discomfort symptoms with the greatest impact on quality of life. We wondered whether the evolutionary stage of the cancer was linked with the prescriptions of opioid analgesics. We observed the prescriptions of strong opioids in patients suffering from metastatic bone cancer 3 months before and after identifying the situation as palliative. This is a cross-sectional observational study performed between January 1, 2012 and December 31, 2016 using data from the French (nationwide claims database). We included 38,399 patients with cancer with at least one metastatic bone location in a palliative situation. Seventeen percent (n=6544) of patients had a prescription of opioid analgesics after palliative care labeling, 19.8 % (n=7606) had a prescription before, 31.1 % (n=11 949) had a prescription before and after and 32.0 % had no prescription of opioid analgesics. An increase in the dosage of opioid analgesics is observed between before and after labeling the stage of the disease as palliative with an average dosage ranging from 99.6 to 142.3mg per day. This study shows that labeling a situation as palliative affects prescriptions of strong opioid analgesics. An early identification of the situation as palliative is essential to provide appropriate care.

[Radiotherapy of bone metastases in France: A descriptive monocentric retrospective study]

PURPOSE

Bone metastases cause pain and affect patients' quality of life. Radiation therapy is one of the reference analgesic treatments. The objective of this study was to compare the current practices of a French radiotherapy department for the treatment of uncomplicated bone metastases with data from the literature in order to improve and optimize the management of patients.

MATERIAL AND METHODS

A retrospective monocentric study of patients who underwent palliative irradiation of uncomplicated bone metastases was performed.

RESULTS

Ninety-one patients had 116 treatments of uncomplicated bone metastases between January 2014 and December 2015, including 44 men (48%) and 47 women (52%) with an average age of 63years (25-88years). Primary tumours most commonly found were breast cancer (35%), lung cancer (16%) and prostate cancer (12%). The regimens used were in 29% of cases 30Gy in ten fractions (group 30Gy), in 21% of cases 20Gy in five fractions (group 20Gy), in 22% of cases 8Gy in one fraction (group 8Gy) and in 28% of cases 23.31Gy in three fractions of stereotactic body irradiation (stereotactic group). The general condition of the patient (P<0.001), pain score and analgesic (P<0.001), oligometastatic profile (P=0.003) and practitioner experience (P<0.001) were factors influencing the choice of the regimen irradiation. Age (P=0.46), sex (P=0.14), anticancer treatments (P=0.56), concomitant hospitalization (P=0.14) and the distance between the radiotherapy centre and home (P=0.87) did not influence the decision significantly. A total of three cases of spinal compression and one case of post-therapeutic fracture were observed, occurring between one and 128days and 577days after irradiation, respectively. Eight percent of all irradiated metastases were reirradiated with a delay ranging between 13 and 434days after the first irradiation. The re-irradiation rate was significantly higher after 8Gy (P=0.02). The rate of death was significantly lower in the stereotactic arm (P<0.001) and overall survival was significantly greater in the stereotactic arm (P<0.001).

CONCLUSION

This study showed that patients' analysed was comparable to the population of different studies. Predictive factors for the choice of the treatment regimen were identified. Non-fractionnated therapy was underutilised while stereotactic treatment was increasingly prescribed, showing an evolution in the management of patients.

[Radiotherapy of bone metastases]

Radiotherapy plays a major role in palliative treatment of bone metastases. Recent developments of stereotactic radiotherapy and intensity modulated radiation therapy give the possibility to treat oligometastatic diseases. The objective of this paper is to report indications and treatment modalities of radiotherapy in these situations.

[Radiotherapy of bone metastases: Which fractionations?]

First-line palliative radiotherapy for painful bone metastases is an effective treatment whatever its fractionation (single or multiple fractions). It is also indicated after failure or insufficient effect of a first irradiation, or the appearance of new painful site. Other indications are spinal cord compression, either as an adjuvant to surgery or as sole treatment, and after surgery for long bone metastases. The development of high precision techniques (stereotactic conditions) widens the possibility of re-irradiation when tolerance doses to normal tissues have already been delivered. Local control and possibly overall survival could be improved in oligometastatic patients.

[Which rules apply to hypofractionated radiotherapy?]

Hypofractionated radiotherapy is now more widely prescribed due to improved targeting techniques (intensity modulated radiotherapy, image-guided radiotherapy and stereotactic radiotherapy). Low dose hypofractionated radiotherapy is routinely administered mostly for palliative purposes. High or very high dose hypofractionated irradiation must be delivered according to very strict procedures since every minor deviation can lead to major changes in dose delivery to the tumor volume and organs at risk. Thus, each stage of the processing must be carefully monitored starting from the limitations and the choice of the hypofractionation technique, tumour contouring and dose constraints prescription, planning and finally dose calculation and patient positioning verification.