Minimizing Risk of Cancer Therapeutics

The clinical manifestations and molecular pathogenesis of radiation fibrosis

Advances in radiation techniques have enabled the precise delivery of higher doses of radiotherapy to tumours, while sparing surrounding healthy tissues. Consequently, the incidence of radiation toxicities has declined, and will likely continue to improve as radiotherapy further evolves. Nonetheless, ionizing radiation elicits tissue-specific toxicities that gradually develop into radiation-induced fibrosis, a common long-term side-effect of radiotherapy. Radiation fibrosis is characterized by an aberrant wound repair process, which promotes the deposition of extensive scar tissue, clinically manifesting as a loss of elasticity, tissue thickening, and organ-specific functional consequences. In addition to improving the existing technologies and guidelines directing the administration of radiotherapy, understanding the pathogenesis underlying radiation fibrosis is essential for the success of cancer treatments. This review integrates the principles for radiotherapy dosimetry to minimize off-target effects, the tissue-specific clinical manifestations, the key cellular and molecular drivers of radiation fibrosis, and emerging therapeutic opportunities for both prevention and treatment.

Percutaneous electrical nerve stimulation in post-mastectomy neuropathic pain: A case report

Post-mastectomy pain syndrome (PMPS) is a type of chronic postsurgical pain that can be severe, debilitating and frequently encountered in clinical practice. Multiple studies have focused on prevention, identifying risk factors and treating this condition. Nonetheless, PMPS remains a complex condition to treat effectively. In this case report, we describe the use of percutaneous electrical nerve stimulation in a breast cancer patient who experienced PMPS refractory to conventional treatments.

Chemotherapy-induced peripheral neuropathy and rehabilitation: A review

Chemotherapy-induced peripheral neuropathy (CIPN) is a common complication after chemotherapy that can damage the sensory, motor, autonomic, or cranial nerves in approximately 30%-60% of patients with cancer. CIPN can lead to detrimental dose modifications and/or premature chemotherapy discontinuation due to patient intolerance. The long-term impact of CIPN is particularly challenging and can have a profound impact on the quality of life (QoL) and survivorship. However, this condition is often underdiagnosed. No agents have been established to prevent CIPN. Pre-chemotherapy testing is recommended for high-risk patients. Duloxetine is considered a first-line treatment, whereas gabapentin, pregabalin, tricyclic antidepressants, and topical compounding creams may be used for neuropathic pain control. Home-based, low-to-moderate walking, and resistance exercise during chemotherapy can reduce the severity and prevalence of CIPN symptoms, especially in older patients. Pre-habilitation and rehabilitation should be recommended for all patients receiving cytotoxic chemotherapies. The purpose of this article is to review common chemotherapeutic drugs causing CIPN, risk factors, diagnosis and treatment of CIPN, and evidence of the benefits of rehabilitation.

Pilot Study in Temporary Peripheral Nerve Stimulation in Oncologic Pain

Objectives

Temporary, percutaneous peripheral nerve stimulation (PNS) has been shown to provide analgesia for acute postoperative pain, postamputation pain, and low back pain. The implanted device stimulates the neural target for up to 60 days at which point the leads are extracted. Patients have demonstrated prolonged analgesia continuing after extraction of the leads. The purpose of this case series is to demonstrate peripheral neural targets that could feasibly be used to treat various pain syndromes prevalent in the oncologic population.

Materials and Methods

A temporary, percutaneous PNS was implanted under ultrasound guidance in 12 oncologic chronic pain patients seen in an outpatient pain clinic who had failed medical and/or interventional management. The device was implanted for up to 60 days. Clinical progress of pain and functional capacity was monitored through regular clinical visits.

Results

The case series presents seven successful cases of implementation of the PNS to treat oncologic pain. Three of these cases demonstrate targeting of proximal spinal nerves to treat truncal neuropathic pain and lumbar radicular pain. The four remaining cases demonstrate successful targeting of other peripheral nerves and brachial plexus. We also share five failed cases without adequate pain relief with PNS.

Conclusions

PNS has potential uses in the treatment of oncologic pain. Further high‐quality studies should be designed to further elucidate use of the PNS to treat oncologic pain.

ERCC1 expression in advanced colorectal cancer and matched liver metastases

BACKGROUND

Platinum-based chemotherapy is part of the standard treatment for patients with colorectal cancer. ERCC1 is a potential predictive biomarker for platinum-based chemotherapy. The aim of this study was to examine interobserver agreement on ERCC1 protein expression in primary colorectal cancer as well as corresponding liver metastasis. Furthermore, comparison of ERCC1-expression in primary tumor and the corresponding liver metastasis was performed.

METHODS

Forty patients with primary colorectal cancers and corresponding liver metastases were included. One slide was stained with the anti-ERCC1 antibody, 4F9 clone (DAKO) and evaluated by two gastrointestinal pathology consultants and a pathology registrar separately. Interobserver agreement was evaluated for primary tumors and liver metastases using kappa (κ) statistics. Discordant scorings were reviewed, and consensus was obtained. The expression in primary tumor was compared with the corresponding liver metastases.

RESULTS

For the primary tumors agreement was found in 85% of the tumors corresponding to an unweighted kappa value of 0,79 (95% CI 0,64-0,94). For the liver metastases agreement was found in 76% corresponding to an unweighted kappa value of 0,64 (95% CI 0,49-0,79). When comparing primary tumors to the corresponding metastases, no concordance in ERCC1-expression was observed.

CONCLUSION

Interobserver agreement of ERCC1 expression was good for both primary tumors and liver metastases, which is crucial for a potential predictive biomarker. As no concordance between primary tumor and liver metastases was found it seems to be of high importance to use tissue from actual tumor burden for evaluation of ERCC1 expression. Further studies and correlation to clinical outcome are warranted.