Symptoms and General Pathology

All Conditions

Behaviors and Mental Disorders

Pain

Quality of Life

Patients aged between 18 and 80 years with cancer-related pain lasting for more than 3 months will be included.

cancer patients

Savaş Şencan, Assoc. Prof.

Ronay Bozyel, M.D.

Serdar Kokar, Assoc. Prof.

Pain is one of the most important and challenging symptoms in cancer patients. Depending on the stage of cancer, approximately 40% to 70% of patients complain of pain. With the increasing lifespan of cancer patients due to developing treatments, pain palliation has become even more crucial to improve their quality of life. Cancer-related pain can develop through multiple mechanisms such as the tumor itself, metastasis, or the methods used in treatment. The type of pain can be nociceptive, neuropathic, or mixed.

Central sensitization refers to the increased response of central nervous system nociceptive neurons to normal or subthreshold stimuli. Recently, central sensitization (CS) has been recognized as a potential pathophysiological mechanism underlying a group of chronic pain diseases such as fibromyalgia, temporomandibular joint disorder, irritable bowel syndrome, interstitial cystitis, tension-type headache, and chronic low back pain. Since pain perception varies from person to person, physicians should assess the character of pain thoroughly and not rely solely on peripheral pain treatment in cases with a component of central sensitization. The lack of evaluation of the extent to which central sensitization affects patients and the failure to fully determine the factors influencing it appear to be clinical limitations for now.

There are studies suggesting that central sensitization may be a significant factor in chronic refractory pain in cancer patients, indicating the need for consideration of alternative options to classical treatments. To the best of our knowledge, no study has been conducted in Turkey to investigate the frequency of central sensitization and its impact on treatment outcomes in chronic cancer pain patients visiting outpatient clinics. The aim of this study is to investigate the frequency of central sensitization and its effect on pain and quality of life in chronic cancer pain patients attending algology clinics in multiple centers in Turkey.

The Role of Central Sensitization in Pain, Functionality, and Quality of Life in Cancer Patients

The study is planned as multicenter, and data transfer will be conducted with other centers.

Central sensitization is a common condition in cancer patients and has negative consequences on pain, functionality, and quality of life.

Marmara University

Neoplasms

Nervous System Diseases

Neoplasm Metastasis

Hyperalgesia

Neoplastic Processes

Somatosensory Disorders

Sensation Disorders

Neurologic Manifestations

High-frequency stimulation will be applied on the volar forearm (6-10 cm distal to the cubital fossa). To avoid any confounding effect of handedness, the arm onto which HFS will be applied twice (dominant vs nondominant) will be counterbalanced across participants. HFS will consist of 12 trains of 42 Hz electrical pulses lasting 1 s each. The time interval between each train will be 10 s. The intensity of stimulation will be 5mA. Electrical pulses will be delivered to the skin using a specifically-designed electrode designed: the cathode consists of 16 blunt stainless-steel pins with a diameter of 0.2 mm protruding 1 mm from the base. The 16 pins are placed in a circle with a diameter of 10 mm. The anode consists of a surrounding stainless-steel ring having an inner diameter of 22 mm and an outer diameter of 40 mm. This procedure induces secondary pinprick hyperalgesia (an increase in pinprick sensitivity in a large area of the skin).

High-frequency electrical stimulation

This study is designed to evaluate the method of assessing the and intensity areas of secondary hyperalgesia induced by High Frequency Stimulation (HFS). Measures of the areas of secondary hyperalgesia will take place on two experimental days separated by a minimum of two weeks. Each experimental day, the areas of secondary hyperalgesia will be assessed three times, starting 30 minutes following HFS. Furthermore, the investigators will assess if anxiety, catastrophization, stress and demographic variables modulate the extend of hyperalgesia.

This prospective cohort study is designed to evaluate the method of assessing the areas and intensity of secondary hyperalgesia following High Frequency Stimulation (HFS), and will consist of two experimental days separated by a minimum of two weeks. During the two each session (Day1 and Day2), subjects will go through the HFS procedure on the same forearm. Then, after a 30 minutes break, the area and intensity of secondary hyperalgesia induced by HFS will be assessed three times (Time9-14), with a two-minute break between each assessment.

Before the experiment, subjects will fill two questionnaires by email : the Spielberger Trait anxiety inventory and the Pain catastrophization scale.The first experimental day, the patients will be seated on a chair and informed consent will be gained. Subjects will provide demographic information to the researcher (age, gender, size) (Time1). Then, the forearm skin of the selected arm will be marked with a pen to improve the precision of subsequent measures. The subject will then observe a period of rest for 5 minutes, to provide a baseline measure of heart rate variability.

Next, the patients will be asked to rate the pain induced by pin-prick stimulation in the area surrounding the electrode (Time2).

Following standardized explanation of the HFS procedure, the subject will fill the Spielberger State anxiety inventory (Time5), and HFS will be applied on the volar forearm (6-10 cm distal to the cubital fossa) (Time6). To avoid any confounding effect of handedness, the arm onto which HFS will be applied (dominant vs nondominant) will be counterbalanced across participants. In summary, HFS will consist of 12 trains of 42 Hz electrical pulses (pulse width: 2 ms) lasting 1 s each. The time interval between each train will 10 s. The intensity of stimulation will be 5mA. Heart rate variability during the HFS procedure will be monitored.

After a 25 minutes break the heart rate variability will be assessed a third time during 5 minutes. During the break, subjects will be asked to stay seated, to fill the Pain Catastrophizing scale (short-version) and give a rating from 0-100 for the pain and stress experienced during the HFS procedure (Time7).

Following this break, the area of secondary hyperalgesia will be assessed with a calibrated 128 mN pinprick probe (The Pin Prick, MRC Systems GmbH, Heidelger, Germany) (Time9). Pokes of 1-second duration will be provided at a frequency of 0.5 Hz, starting well outside and approaching the stimulation site with steps of 0,5 cm from 4 different directions towards the application site. Participants will be asked to keep their eyes closed during the entire mapping procedure. Then, participants will rate the pain induced by pin-prick stimulation in the area surrounding the electrode (Time10). This procedure will be conducted three times, with a two-minute break between each assessment (Time 11-14).

The second experimental day (Day2), the procedure will be similar to the first, but informed consent and the Spielberger Trait anxiety inventory and the Pain catastrophization scale will not be filled.

Reliability of Measuring the Area and Intensity of Secondary Hyperalgesia Induced by High Frequency Stimulation

Test-retest Reliability of Measuring the Area and Intensity of Secondary Hyperalgesia Induced by High Frequency Stimulation of Skin Nociceptors

the area of secondary hyperalgesia (cm square) will be assessed with a calibrated 128 mN pinprick probe (The Pin Prick, MRC Systems GmbH, Heidelger, Germany). Pokes of 1-second duration will be provided at a frequency of 0.5 Hz, starting well outside and approaching the stimulation site with steps of 0,5 cm from 4 different directions towards the application site. Participants will be asked to keep their eyes closed during the entire mapping procedure.

participants will rate the pain induced by pin-prick stimulation in the area surrounding the electrode on a numerical rating scale ranging from 0 (no perception) to 100 (maximal pain), with 50 representing the transition from nonpainful to painful domains of sensation

questionnaire assessing the state of anxiety. The score will range from 20 (low state anxiety) to 80 (high state anxiety).

questionnaire assessing the trait of anxiety. The score will range from 20 (low trait anxiety) to 80 (high trait anxiety). This questionnaire will be sent by email to the participant.

questionnaire to assess thoughts and emotions in response to pain. The score will range from 0 (low catastrophization) to 52 (high catastrophization).

questionnaire to assess thoughts and emotions in response to a specific painful event. The score will range from 0 (low catastrophization) to 24 (high catastrophization).

Stress on a scale from 0 (low stress) to 100 (maximal stress).

Lowest intensity at which the participant feels the electrical pulse

changes in the time interval between heart beats through the study completion.

Study title	NCT ID	Conditions	Interventions	Eligibility	Organization
The Role of Central Sensitization in Pain, Functionality, and Quality of Life in Cancer Patients	NCT06418399	Central Sensiti...	cancer patients	18 Years - 80 Years	Marmara University
The Role of Central Sensitization in Pain, Functionality, and Quality of Life in Cancer Patients	NCT06418399	Central Sensiti...	cancer patients	18 Years - 80 Years	Marmara University
Reliability of Measuring the Area and Intensity of Secondary Hyperalgesia Induced by High Frequency Stimulation	NCT03966508	Hyperalgesia, S...	High-frequency ...	18 Years - 40 Years	Université Catholique de Louvain

Spots Global Cancer Trial Database for central sensitization