Long-term effect and prognostic factors of a low-dose radiotherapy of painful plantar calcaneal spurs : A retrospective unicenter study

Comparative effectiveness of kilo- and megavoltage energies in low-dose radiotherapy for painful degenerative musculoskeletal diseases: a systematic review and meta-analysis

PURPOSE

This study aimed to assess the impact of different energy levels on the effectiveness of low-dose radiotherapy (LDRT) for treating painful degenerative musculoskeletal diseases, as comparative efficacy data are currently lacking.

METHODS

A systematic review was conducted in PubMed, Embase, and the Cochrane Library databases to identify studies with response information on the energy used (kilovoltage [kV] vs. megavoltage [MV]). The primary endpoint was the overall response rate (ORR), and the secondary endpoint was the complete response rate (CRR). Exploratory subgroup analyses included treatment site, study period, study design, country, and dose per fraction.

RESULTS

A total of 33 studies involving 12,143 patients were analyzed. Short-term follow-up (up to 6 months) showed a pooled ORR of 64% (95% CI 46-78%) for kV and of 62% (95% CI 54-70%) for MV. Long-term follow-up (at least 12 months) revealed a pooled ORR of 85% (95% CI 65-95%) for kV and of 69% (95% CI 62-75%) for MV. Subgroup analysis indicated no significant differences in ORR for energy level stratified by treatment site and other factors. Regarding dose per fraction (0.5 Gy vs. 1.0 Gy), comparable ORRs were demonstrated between the two energies. No clinical side effects were noted.

CONCLUSION

This meta-analysis suggests that the known effectiveness of LDRT in painful degenerative musculoskeletal disease may not depend on the energy used. Additional studies using standardized evaluation methods are warranted to establish consistency and enhance the comprehensiveness of research. Further research is also needed to explore treatment modality selection considering disease-specific biology.

Low-dose radiotherapy for greater trochanteric pain syndrome-a single-centre analysis

PURPOSE

To determine predictive factors associated with a good response (GR) to and efficacy of low-dose radiotherapy (LDRT) in patients with greater trochanteric pain syndrome (GTPS).

METHODS

Patients with GTPS were irradiated on a linear accelerator with 0.5-1.0 Gy per fraction to a total dose of 3.0-4.0 Gy per series. The endpoint was subjective good response (GR) to treatment 2 months after completion of the last LDRT series, defined as complete pain relief or marked improvement assessed using the von Pannewitz score. A positive response to steroid injection (SI) was defined as pain relief of at least 7 days. Patient and treatment-related characteristics were evaluated with respect to LDRT outcomes.

RESULTS

Outcomes were assessed for 71 peritrochanteric spaces (PTSs; 65 patients, 48 females, with mean age of 63 [44-91] years). Prior SI had been given to 55 (77%) PTSs and 40 PTSs received two series of LDRT. Two months after completion of LDRT, GR was reported in 42 PTSs (59%). Two series of LDRT provided a significantly higher rate of GR than one series (72.5 vs. 42% PTSs, p = 0.015). Temporary pain relief after prior SI predicted GR to LDRT compared with PTSs which had not responded to SI (73 vs. 28% PTSs, p = 0.001). A regional structural abnormality, present in 34 PTSs (48%), was associated with a reduction of GR to LDRT (44 vs. 73% PTSs, p = 0.017).

CONCLUSION

LDRT is an effective treatment for GTPS. Administration of two LDRT series, prior response to SI, and absence of structural abnormalities may predict significantly better treatment outcomes.

Non-Oncological Radiotherapy: A Review of Modern Approaches

Despite being usually delivered in oncological patients, radiotherapy can be used as a successful treatment for several non-malignant disorders. Even though this use of radiotherapy has been scarcely investigated since the 1950s, more recent interest has actually shed the light on this approach. Thus, the aim of this narrative review is to analyze the applications of non-oncological radiotherapy in different disorders. Key references were derived from a PubMed query. Hand searching and clinicaltrials.gov were also used. This review contains a narrative report and a critical discussion of non-oncological radiotherapy approaches. In conclusion, non-oncological radiotherapy is a safe and efficacious approach to treat several disorders that needs to be further investigated and used in clinical practice.

Low-Dose Radiotherapy Leads to a Systemic Anti-Inflammatory Shift in the Pre-Clinical K/BxN Serum Transfer Model and Reduces Osteoarthritic Pain in Patients

Osteoarthritis (OA) is the leading degenerative joint disease in the western world and leads, if left untreated, to a progressive deterioration of joint functionality, ultimately reducing quality of life. Recent data has shown, that especially OA of the ankle and foot are among the most frequently affected regions. Current research in OA points towards a complex involvement of various cell and tissue types, often accompanied by inflammation. Low-dose radiotherapy (LDRT) is widely used for the treatment of degenerative and inflammatory diseases. While the reported analgesic effects are well known, the underlying molecular mechanisms are only poorly understood. We therefore correlated a clinical approach, looking at pain reduction in 196 patients treated with LDRT with a pre-clinical approach, utilizing the K/BxN serum transfer mouse model using flow cytometry and multiplex ELISA for analysis. While an improvement of symptoms in the majority of patients was found, patients suffering from symptoms within the tarsi transversa show a significantly lower level of improvement. Further, a significant impact of therapy success was detected depending on whether only one or both feet were affected. Further, patients of younger age showed a significantly better outcome than older ones while needing fewer treatment series. When looking on a cellular level within the mouse model, a systemic alteration of immune cells namely a shift from CD8+ to CD4+ T cells and reduced numbers of DCs was observed. A general reduction of inflammatory cytokines was detected, with significant alterations in IL-4 and IL-17 levels, all of which could potentially be responsible for the highly effective clinical improvement in patients. Taken together our data indicate that LDRT can be regarded as a highly effective treatment option for patients suffering from OA of the foot and ankle, in terms of analgesic effects, especially in younger patients. Furthermore, the observed effects are mediated by an interplay of cellular and soluble immune factors, as observed in the K/BxN serum transfer model. With this interdisciplinary approach we aim to encourage the usage of LDRT as an additive treatment strategy not only as a last resort, but also earlier in the course of disease.