Palliative radiotherapy for bone metastases from lung cancer: Evidence-based medicine?

Metastatic bone cancer: Consideration for optimal dose fractionation in radiation therapy

The bones are one of the most common sites for metastatic cancer spread. Unfortunately, there is no current known cure for many people affected by bone metastasis. Therefore, the treatment intent for radiotherapy remains a palliative objective, whereby treatments are meant to provide pain relief and alleviate symptoms. However, some debate has arisen in recent decades regarding the most appropriate dose prescription pertaining to dose protraction and fractionation. By delivering a larger dose in fewer fractions, patients can spend less time at the hospital and more time with loved ones. Additionally, many dose prescriptions were prioritized to be shortened during the COVID-19 pandemic, which may offer retrospective data on the treatment outcomes from providing shortened courses of radiotherapy.

Bone-Specific Metastasis Pattern of Advanced-Stage Lung Adenocarcinoma According to the Localization of the Primary Tumor

Background: Patients with advanced-stage lung adenocarcinoma (LADC) often develop distant metastases in the skeletal system. Yet, the bone-specific metastasis pattern is still controversial. We, therefore, aimed to examine how the primary tumor location affects bone specificity and survival in LADC patients diagnosed with skeletal metastases. Methods: In total, 209 bone-metastatic Caucasian LADC patients from two thoracic centers were included in this study. Focusing on the specific location of primary tumors and bone metastatic sites, clinicopathological variables were included in a common database and analyzed retrospectively. Skeletal metastases were diagnosed according to the contemporary diagnostic guidelines and confirmed by bone scintigraphy. Besides region- and side-specific localization, primary tumors were also classified as central or peripheral tumors based on their bronchoscopic visibility. Results: The most common sites for metastasis were the spine (n = 103) and the ribs (n = 60), followed by the pelvis (n = 36) and the femur (n = 22). Importantly, femoral (p = 0.022) and rib (p = 0.012) metastases were more frequently associated with peripheral tumors, whereas centrally located LADCs were associated with humeral metastases (p = 0.018). Moreover, we deduced that left-sided tumors give rise to skull metastases more often than right-sided primary tumors (p = 0.018). Of note, however, the localization of the primary tumor did not significantly influence the type of affected bones. Multivariate Cox regression analysis adjusted for clinical parameters demonstrated that central localization of the primary tumor was an independent negative prognostic factor for overall survival (OS). Additionally, as expected, both chemotherapy and bisphosphonate therapy conferred a significant benefit for OS. Conclusion: The present study demonstrates unique bone-specific metastasis patterns concerning primary tumor location. Peripherally located LADCs are associated with rib and femoral metastases and improved survival outcomes. Our findings might contribute to the development of individualized follow-up strategies in bone-metastatic LADC patients and warrant further clinical investigations on a larger sample size.

Machine Learning Algorithm Guiding Local Treatment Decisions to Reduce Pain for Lung Cancer Patients with Bone Metastases, a Prospective Cohort Study

INTRODUCTION

As life expectancy increases for lung cancer patients with bone metastases, the need for personalized local treatment to reduce pain is expanding.

METHODS

Patients were treated by a multidisciplinary team (MDT), and local treatment including surgery, percutaneous osteoplasty, or radiation. Visual analog scale (VAS) and quality of life (QoL) scores were analyzed. VAS at 12 weeks after treatment was the main outcome. We developed and tested machine learning models to predict which patients should receive local treatment. Model discrimination was evaluated by the area under curve (AUC), and the best model was used for prospective decision-making accuracy validation.

RESULTS

Under the direction of MDT, 161 patients in the training set, 32 patients in the test set, and 36 patients in the validation set underwent local treatment. VAS in surgery, percutaneous osteoplasty, and radiation groups decreased significantly to 4.78 ± 1.28, 4.37 ± 1.36, and 5.39 ± 1.31 at 12 weeks, respectively (p < 0.05), with no significant differences among the three datasets, and improved QoL was also observed (p < 0.05). A decision tree (DT) model that included VAS, bone metastases character, Frankel classification, Mirels score, age, driver gene, aldehyde dehydrogenase 2, and enolase 1 expression had a best AUC in predicting whether patients would receive local treatment of 0.92 (95% CI 0.89-0.94) in the training set, 0.85 (95% CI 0.77-0.94) in the test set, and 0.88 (95% CI 0.81-0.96) in the validation set.

CONCLUSION

Local treatment provided significant pain relief and improved QoL. There were no significant differences in reducing pain and improving QoL among training, test, and validation sets. The DT model was best at determining whether patients should receive local treatment. Our machine learning model can help guide clinicians to make local treatment decisions to reduce pain.

TRIAL REGISTRATION

Trial registration number ChiCRT-ROC-16009501.

Image-guided Cryotherapy for Musculoskeletal Tumors

BACKGROUND

This article represents a review of the use of image-guided cryotherapy in the treatment of musculoskeletal tumor lesions. Cryotherapy is able to induce a lethal effect on cancer cells through direct and indirect mechanisms. In this manuscript, we combined our experience with that of other authors who have published on this topic in order to provide indications on when to use cryotherapy in musculoskeletal oncology.

DISCUSSION

Image-Guided percutaneous cryotherapy is a therapeutic method now widely accepted in the treatment of patients with musculoskeletal tumors. It can be used both for palliative treatments of metastatic bone lesions and for the curative treatment of benign bone tumors, such as osteoid osteoma or osteoblastoma. In the treatment of bone metastases, cryotherapy plays a major role in alleviating or resolving disease-related pain, but it has also been demonstrated that it can have a role in local disease control. In recent years, the use of cryotherapy has also expanded for the treatment of both benign and malignant soft tissue tumors.

CONCLUSION

Percutaneous cryotherapy can be considered a safe and effective technique in the treatment of benign and malignant musculoskeletal tumors. Cryotherapy can be considered the first option in benign tumor lesions, such as osteoid osteoma, and a valid alternative to radiofrequency ablation. In the treatment of painful bone metastases, it must be considered secondarily to other standard treatments (radiotherapy, bisphosphonate therapy, and chemotherapy) when they are no longer effective in controlling the disease or when they cannot be repeated (for example, radiotherapy).

The effects of bisphosphonate and radiation therapy in bone-metastatic lung adenocarcinoma: the impact of KRAS mutation

Background

KRAS mutation is the most common genetic alteration in lung adenocarcinoma (LADC) in Western countries and is associated with worse outcome in bone-metastatic cases. Yet, to date, no effective treatment guidelines were developed for these patients. Accordingly, our aim was to investigate the impact of KRAS mutation on bisphosphonate (BTx) and radiation therapy (RTx) in bone-metastatic LADC patients.

Methods

Clinicopathological variables of 134 consecutive LADC patients with bone metastases at diagnosis and known KRAS status were retrospectively analyzed. The effects of BTx, RTx and KRAS mutation on overall survival (OS) were investigated.

Results

Of the total cohort, 93 patients were identified as KRAS wild-type (WT) (69.4%) and 41 (30.6%) as KRAS mutant patients. The presence of KRAS mutation was associated with significantly reduced median OS (5.1 vs. 10.2 months in KRAS WT patients; P=0.008). Irrespective of KRAS mutational status both BTx (P=0.007) and RTx (P=0.021) conferred a significant benefit for OS. Notably, however, when analyzing the patients with KRAS-mutant and KRAS WT tumors separately, the benefit from BTx and RTx on OS remained statistically significant only in KRAS WT patients (P=0.032 and P=0.031, respectively).

Conclusions

KRAS mutation is a strong negative prognostic factor in bone-metastatic LADC patients. Both BTx and RTx can increase the OS with a pronounced benefit for patients with KRAS WT tumors. Altogether, KRAS mutational status should be considered during therapeutic decision making in bone-metastatic LADC patients.

Diffusion-weighted magnetic resonance imaging in painful bone metastases: Using quantitative apparent diffusion coefficient as an indicator of effectiveness of single fraction versus multiple fraction radiotherapy

PURPOSE

Bone metastases are a common cause of cancer-related pain. The aim of this study is to determine the optimal radiotherapy schedule for the treatment of painful bone metastases and verify if could cause different biological effects on bone. This has been achieved using functional Magnetic Resonance Imaging (MRI) with diffusion-weighted imaging (DWI).

PATIENTS AND METHODS

Fifteen patients received Multiple Fractions Radiation Therapy (MFRT) with a total dose of 30Gy in 10 daily fractions of 3Gy given over 2 weeks and 15 patients received a Single Fraction Radiation Therapy (SFRT) with a dose of 8Gy. Quantitative Apparent Diffusion Coefficient (ADC) values after SFRT or MFRT were compared with response to treatment (pain relief), assessed by Visual Analogue Scale (VAS) before radiotherapy and at 1 and 3 months after the completion of treatment.

RESULTS

The two schedules had equal efficacy in terms of pain control, without any difference at 1 and 3 months post radiotherapy. In both treatments, pain reduction was related to an increase in the ADC. However, the median ADC value had an increase of 575 points between the baseline and 3 months (from 1010 to 1585, p=0.02) in the 30Gy group, while it was only 178 points (from 1417 to 1595) in the 8Gy group.

CONCLUSIONS

The increase in the ADC values after radiotherapy corresponds to increased cell death. Despite an equal pain control, MFRT treatment seems to be more effective to achieve cancer cells kill. Our preliminary data could also explain the higher retreatment rates in SFRT vs MFRT in long survivors.

Incidence and treatment patterns of complicated bone metastases in a population-based radiotherapy program

INTRODUCTION

There is abundant evidence in support of single fraction (SF) radiation therapy (RT) for uncomplicated bone metastases (BoM). We sought to determine the proportion of BoM that is complicated in a population-based RT program in order to act as a potential guide for assessing SFRT utilization rates.

MATERIALS AND METHODS

A total of 3200 RT courses were prescribed to 1880 consecutive patients diagnosed with BoM in 2013. Associations between choice of RT fractionation and BoM characterization, whether complicated or not, were assessed with logistic regression.

RESULTS

The incidence of complicated BoM was 34.4%, resulting most often from adverse features of actual pathological fracture (42.1%), and neurological compromise (36.3%). Complicated BoM were most common in lung cancers (24.2%) and in the spine (68.5%), followed by extremity (15.2%) and pelvis (14.4%). SFRT was prescribed less commonly in complicated versus un-complicated BoM (39.4% vs. 70.4%; p<0.001), which was confirmed on multivariable analysis (OR 0.32; 95% CI 0.28-0.61; p<0.001).

CONCLUSIONS

This study found that 34.4% of BoM are complicated by fracture, or neurological compromise (i.e. 65.6% were un-complicated), and that they were less likely to receive SFRT. A reasonable benchmark for SFRT utilization should be at least 60%.