Cancer pain – progress and ongoing issues in Singapore

Cancer is the leading cause of mortality in Singapore, accounting for 26.5% to 28.5% of deaths between 2004 and 2007 (1). The Ministry of Health in Singapore responded by setting up comprehensive screening and management strategies for each disease, with development of cancer facilities and services to address the issue. What we have been slower to do is to address needs of patients who fail to respond to treatment and succumb to their disease despite oncological care.

The hospice movement was first started in Singapore in 1985 (2). However, it was only as recently as May 2007 that palliative medicine was finally recognized as a subspecialty, giving it the status and importance needed to promote the agenda of providing excellent symptom care and support to terminally ill patients and their families.

Presently, there are five acute hospital-based palliative care services in Singapore. Patients living with life-limiting illnesses in the community are supported by home-based hospice teams, while four hospice units provide inpatient care for up to 125 patients. Symptom management remains a core component of the work performed across each site of care, particularly the care of patients with cancer pain.

Analgesic availability in Singapore

Morphine is readily available in Singapore, as are the other analgesics recommended on the World Health Organization pain step ladder, with the exception of hydromorphone, which is not available yet. Per capita global consumption of morphine in Singapore for 2001 was 1.0027 mg, against a global mean of 5.73 mg (3). Although cancer pain physicians in Singapore have access to methadone and oxycodone, use is limited to the oral route. This poses practical challenges to continued use in patients who, for a variety of reasons, are no longer able to consume medications orally. When continued administration is required in the parenteral form, rotation to other opioids such as morphine or fentanyl is necessary, possibly disrupting symptom management. Not surprisingly, methadone is under-used, despite evidence of benefit in patients suffering from complex neuropathic pain. With only a small population of patients using methadone for the management of difficult pain, it is not economically viable for the local health authority to substantiate the presence of a parenteral counterpart. This has implications not only in the care of patients, but the future training of palliative care physicians in cancer pain.

Ketamine is an alternative option for such patients with difficult pain and is being used with increasing frequency. Adjuvants such as tricyclic antidepressants and gabapentin have proven to be useful allies in neuropathic cancer pain.

Cancer pain collaboration

Responding to ‘pain as a fifth vital sign’, formal pain management services led by anesthesia departments were established across all Singapore hospitals in the past five years. Patients with cancer pain are increasingly being referred for interventions such as neurolytic blocks or insertion of intrathecal catheters that allow patients to remain at home with the support of the community hospice teams.

Pain is a multidimensional experience. Our ability to help our patients is dependent on our fellow team members who include palliative social workers and nurses. The number of such specialized social workers and nurses is presently still too small to deal with the burgeoning numbers of terminally ill patients and their families, and the risk of burnout is high. End-of-life care has recently gained attention in the popular press in Singapore and efforts are being made to train more people in the field of palliative medicine. In time, a palliative care team in Singapore may also include psychologists, physical therapists and pastoral care workers.

Cancer pain management: The way forward in Singapore

1. Use of validated measures such as the Edmonton Symptom Assessment System (4) or the Memorial Pain Assessment Card (5) – simple bedside tools that will provide outcome data guiding analgesic treatment and knowledge;

2. Availability of opioids such as methadone (6) and oxycodone in the parenteral form, allowing cancer pain physicians greater flexibility;

3. Acknowledging the complexity of cancer pain and the need for an interdisciplinary approach. Funding needs to increase to support a coordinated service that is able to meet the needs of patients;

4. Continued recruitment and training of more physicians in the management of cancer pain, widening the access of patients to good symptom control; and

5. Reissuing cancer pain guidelines based on local knowledge of analgesic response and availability.

Palliative care in Singapore has grown over the past few years and has benefited recently by public interest in end-of-life care. There are challenges that include the recruitment, education and retention of health care professionals interested in this field. Our clinical management of cancer pain needs to be reviewed and audited, and further research in this field in our part of the world will help inform our practice.