The Role of Ablation in Cancer Pain Relief

Lung Needle Biopsy and Lung Ablation: Indications, Patient Management, and Postprocedure Imaging Findings

The clinical role and use of percutaneous transthoracic needle biopsy (TTNB) and ablation of lung tumors are evolving. Here we discuss important considerations for referring providers, including current and emerging indications supported by guidelines, critical aspects of pre and postprocedure patient management, and expected postprocedure imaging findings.

Efficacy and Safety of Ketamine to Treat Cancer Pain in Adult Patients: A Systematic Review

CONTEXT

Ketamine is a well-characterized anesthetic agent, and subanesthetic ketamine possesses analgesic effects in both acute and chronic pain.

OBJECTIVES

A systematic review was performed to ascertain the efficacy and safety of ketamine in treating pain for cancer patients.

METHODS

Eight databases were searched from the inception to March 20th, 2023 to obtain randomized controlled trials (RCTs) on ketamine for treating pain in cancer patients. Two reviewers independently screened studies, extracted the data and assessed the risk of bias of included studies; then, meta-analysis was performed by using Revman 5.3 software and Stata 14.0 software.

RESULTS

Thirty-five studies were included, involving 2279 patients with cancer pain. The results of meta-analysis showed that ketamine could significantly reduce pain intensity. Subgroup analysis revealed that, when compared with control group, ketamine decreased markedly visual analogue scale (VAS) scores in two days after the end of treatment with ketamine, and ketamine administrated by patient controlled epidural analgesia (PCEA) was effective. Meanwhile, ketamine could significantly reduce the number of patient-controlled analgesia (PCA) compressions within 24 hours and morphine dosage. Ketamine could not decrease Ramsay sedation score. Additionally, the adverse events significantly decreased in the ketamine group, including nausea and vomiting, constipation, pruritus, lethargy, uroschesis, hallucination, and respiratory depression. In addition, compared with the control group, ketamine could reduce Hamilton depression scale (HAMD) score and relieve depressive symptoms.

CONCLUSION

Ketamine may be used as an effective therapy to relieve cancer pain. However, more rigorously designed RCTs with larger sample sizes are required to verify the above conclusions.

Role of interventional radiology in pain management in oncology patients

This article reviews the current evidence of interventional radiology procedures for patients suffering with debilitating cancer pain, refractory to conventional therapies. Cancer pain is notoriously difficult to treat. Up to 90% of cancer patients experience pain with 56-82% of cancer pain controlled inadequately. Cancer pain influences a patient's ability to perform normal daily activities, causes higher risk of depression, and reduces quality of life. Pain-free status has been universally voted as a "good death". Alternative minimally invasive options include nerve blocks, neurolysis, bone ablation, spine and peripheral musculoskeletal augmentation techniques, embolisation, and cordotomy with evidence highlighting improved pain control, reduced analgesic requirements, and improved quality of life. Unfortunately, awareness and availability of these procedures is limited, potentially leaving patients suffering during their remaining life. The purpose of this review is to describe the basic concepts of interventional radiology techniques for pain palliation in oncology patients. In addition, emphasis will be given upon the need for an individually tailored approach aiming to augment efficacy and safety.

Ablative Techniques for Sarcoma Metastatic Disease: Current Role and Clinical Applications

Sarcomas are heterogenous mesenchymal neoplasms with more than 80 different histologic subtypes. Lung followed by liver and bone are the most common sites of sarcoma metastatic disease. Ablative techniques have been recently added as an additional alternative curative or palliative therapeutic tool in sarcoma metastatic disease. When compared to surgery, ablative techniques are less invasive therapies which can be performed even in non-surgical candidates and are related to decreased recovery time as well as preservation of the treated organ’s long-term function. Literature data upon ablative techniques for sarcoma metastatic disease are quite heterogeneous and variable regarding the size and the number of the treated lesions and the different histologic subtypes of the original soft tissue or bone sarcoma. The present study focuses upon the current role of minimal invasive thermal ablative techniques for the management of metastatic sarcoma disease. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of metastatic soft tissue and bone sarcoma, including local control and survival rates.

Management of cancer pain due to bone metastasis

Bone metastases frequently occur in patients with cancer. Skeletal-related events (SREs), including pain, impaired mobility, hypercalcemia, pathological fracture, spinal cord and nerve root compression, and bone marrow infiltration, can decrease the quality of life of the patients and increase the risk of morbidity. The mechanism of pain due to bone metastasis is complicated and involves various interactions among tumor cells, bone cells, activated inflammatory cells, and bone-innervating neurons. Cancer pain due to bone metastasis can be crippling and a chronic state that causes sarcopenia. For pain management, it is important to diagnose whether the pain is based on background pain or breakthrough pain due to bone metastasis. In addition, the management goal of cancer pain due to bone metastasis is not only to achieve pain relief but also to prevent pain progression and SREs. Pain mechanisms should be applied to achieve optimal management. This review aims to discuss the mechanisms of cancer pain due to bone metastasis and review the recommended drug therapies.

Neurotoxins subvert the allosteric activation mechanism of SARM1 to induce neuronal loss

SARM1 is an inducible TIR-domain NAD+ hydrolase that mediates pathological axon degeneration. SARM1 is activated by an increased ratio of NMN to NAD+, which competes for binding to an allosteric activating site. When NMN binds, the TIR domain is released from autoinhibition, activating its NAD+ hydrolase activity. The discovery of this allosteric activating site led us to hypothesize that other NAD+-related metabolites might activate SARM1. Here, we show the nicotinamide analog 3-acetylpyridine (3-AP), first identified as a neurotoxin in the 1940s, is converted to 3-APMN, which activates SARM1 and induces SARM1-dependent NAD+ depletion, axon degeneration, and neuronal death. In mice, systemic treatment with 3-AP causes rapid SARM1-dependent death, while local application to the peripheral nerve induces SARM1-dependent axon degeneration. We identify 2-aminopyridine as another SARM1-dependent neurotoxin. These findings identify SARM1 as a candidate mediator of environmental neurotoxicity and suggest that SARM1 agonists could be developed into selective agents for neurolytic therapy.

Cancer induced bone pain: current management and future perspectives

Recent improvements in the therapeutic armamentarium of oncology by the addition of targeted and immunotherapeutic agents have led to an increase in the life expectancy of advanced-stage cancer patients. This has led to an increased number of patients presenting with bone metastasis and experiencing episodes of cancer-induced bone pain (CIBP). CIBP is a crippling, chronic, morbid state interfering significantly with the functional capacity and the quality of life (QoL). CIBP is characterized by a complex multifactorial pathophysiological mechanism involving tumor cells, bone cells, inflammatory microenvironment, and the neuronal tissue. It may not be possible to mitigate pain completely; therefore, the aim should be to reach the lowest possible level of pain that allows for an acceptable QoL to the patient. Multimodality approach of surgical, radiation, medical and behavioral techniques is thus recommended to manage CIBP. This review discusses the pathogenesis and pathophysiological mechanism accompanying bone metastasis and CIBP, currently approved therapies for the management of CIBP, and the future perspective.