An observational study in Breast Cancer, Chronic Pain and Acute Pain, sponsored by KK Women's and Children's Hospital. Active, not recruiting at 2 sites in 2 countries. Open to female participants aged 21 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-08-07.
Sponsored by KK Women's and Children's Hospital · Observational
Pre-existing pain and severe postoperative pain are predictors of persistent pain after surgery, but a complete understanding on the development of persistent pain is still lacking. The study aims to identify clinically relevant and genetic risk factors for persistent postsurgical pain that can be reliably distinguished statistically.
The study will focus on: (i) risk factors representing biopsychosocial processes that influence chronic pain, such as pain and psychological vulnerability; (ii) genetic factors relating to mechanistic pathways to persistent pain generation. Patients will be recruited from those undergoing breast cancer surgery at the mentioned site. Pain and anxiety assessment will be conducted via visual analogue scoring, mechanical temporal summation assessment and a series of questionnaires. After the surgery, all patients will be given appropriate analgesia, and the pain score and analgesia usage will be recorded. Phone survey will be conducted 4 and 6 months, respectively, after surgery to determine the outcomes.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 220 is above the median of 184 across 3,235 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →KK Women's and Children's Hospital is the lead sponsor of 137 studies on the registry; 33 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients undergoing breast cancer surgery
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Questionnaires, Mechanical Temporal Summation assessment and pain threshold assessment will be assigned to patient. Within this cohort, some patients will have high pain score recorded (persistent pain) during the follow-up evaluations at 4 and 6 months.
Other: Questionnaires · Other: Mechanical Temporal Summation assessment · Other: Pain threshold assessment
Questionnaires including Pain catastrophizing scale (PCS), Central Sensitisation Inventory (CSI), Coping Strategies Questionnaire-Revised (CSQ-R), Brief Symptom Inventory-18 (BSI-18), Perceived Stress Scale (PSS), EQ-5D-3L and Eysenck Personality Questionnaire (EPQ) will be administered to the patient.
A 180 gram von Frey filament is applied on the subject's forearm. Patient will then be asked to rate the pinprick pain score on a verbal rating scale, 0-100. Following this, 10 consecutive touches at random locations are applied with a 1 second interstimulus interval and within a 1 cm diameter circle. The patient will then be asked to rate the 10th pain score (0-100). The Mechanical Temporal Summation Score is obtained by the difference between the 11th pain score and the 1st pain score. If the score is greater than zero, the patient is implied to have presence of Mechanical Temporal Summation.
Also known as: MTS
Pressure is applied 90 degree straight down force on the subject's right/left centre of the trapezius muscle using an algometer, with a speed of pressure \~ 1kgf/s. The above procedure is then repeated 3 times at each site (left/right) which is indicated on the pressure mark with each time having the reading recorded. When patient shows no response ≥ 6kgf, the threshold is recorded as 6kgf. The patient upon feeling pain will say stop or raise the hand to terminate the test. The mean value is obtained by averaging the readings and will then be recorded as the threshold estimate.
Also known as: Pressure pain
Persistent pain at 4 months after surgery
Persistent pain is defined as having one of the below criteria at 4 months after surgery: i) having pain score at rest (Numeric Rating Scale 0 to 100) of 30 or more; or ii) having pain score on movement (Numeric Rating Scale 0 to 100) of 30 or more; or iii) or "yes" to one of the seven questions on the presence of pain in daily life activities (mood, walking, carrying heavy loads, work, relations with people, sleep, enjoyment of life)
Time frame: 4 months after surgery
Persistent pain at 6 months after surgery
Persistent pain is defined as having one of the below criteria at 4 months after surgery: i) having pain score at rest (Numeric Rating Scale 0 to 100) of 30 or more; or ii) having pain score on movement (Numeric Rating Scale 0 to 100) of 30 or more; or iii) or "yes" to one of the seven questions on the presence of pain in daily life activities (mood, walking, carrying heavy loads, work, relations with people, sleep, enjoyment of life)
Time frame: 6 months after surgery
Maximum Acute post-operative pain score
The maximum number of patient-reported post-operative pain score (Numeric Rating Scale 0 to 100) at 0 - 72 hours
Time frame: Up to 3 days after surgery
Opioid consumption
The total opioid consumption (morphine/ fentanyl/ hydromorphone/ oxycodone/ hydrocodone etc) throughout the 72 hours. The opioid consumption will be converted using oral morphine equivalent (OME) conversion calculations.
Time frame: Up to 3 days after surgery
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Started Jan 2018 (actual). Primary completion is estimated for Dec 2026, 107 months after the start.
Of 1,191 non-industry observational studies under Breast Neoplasms, half reached primary completion within 58 months of starting (the median), counting those still running; a quarter within 25 and three quarters within 139. This study's planned 107 months is above that.
Counting every sponsor, half of 1,380 studies reached it within 55 months; a quarter within 25 and three quarters within 126.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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