Treatment of chronic pain in cancer patients.

Chronic pain occupies one of the leading places in oncology among severe pathological syndromes and occurs in about 90% of patients at the stage of a widespread oncological process. The significance of this problem lies in the fact that about 6 million cases of various forms of cancer are detected annually in the world, and more than 4 million people die from cancer every year, which is 10% of the total number of deaths.

Given that the vast majority of cancer patients in the final stage of the disease are at home, an urgent task is to develop and put into practice highly effective, safe, well-tolerated methods of eliminating chronic pain, suitable for widespread use in home and outpatient settings.

Chronic pain accompanies almost all advanced forms of malignant tumors and differs significantly from acute pain in various manifestations due to the constancy and strength of the feeling of pain.

The International Association for the Study of Pain has defined pain as "an unpleasant sensation and emotional experience associated with real or possible tissue damage."  It is believed that acute pain that persists for 3 to 6 months without eliminating the cause that caused it, becomes an independent pathological process that can be classified as a chronic pain syndrome.

A single tactic for the treatment of chronic pain is used, based on strict compliance with the appointment of pain relief agents, depending on the degree of pain intensity. The latter is set on a 4-point scale:

0 –no pain;

1-mild pain;

2-moderate pain;

3-severe pain;

4 –very severe pain.

Narcotic drugs are prescribed for 3-4-point acuity (intensity) of pain.

Monotherapy with narcotic drugs in the treatment of chronic pain should not be used.

Chronic pain syndrome (CBS) of oncological genesis is diverse for the reasons that led to its development and clinical manifestations, and most importantly, it does not have any specific features, except for constancy and progressive nature. This determines the need for early diagnosis and timely initiation of effective comprehensive treatment of chronic pain and its manifestations.  An important role in the correct choice of treatment tactics is played by methods of diagnosing the type and causes of the intensity of CBC, as well as monitoring the effectiveness of the therapeutic measures carried out at the stages of monitoring the patient.

The diagnosis of CKD should be based on the use of simple non-invasive methods for assessing the intensity of pain, the quality of life of the patient and the tolerability of the pain treatments used. The symptoms are taken into account before and during treatment.

In incurable cancer patients, several types of pain can be observed simultaneously; their differential diagnosis is difficult. Depending on the expected type and intensity of CBS, various approaches to its elimination are used.

Drug therapy (pharmacotherapy) is the main method of treating CKD of various types and intensity. In the traditional version, recommended by the WHO committee of experts in 1986, non-narcotic and narcotic analgesics are used for the treatment of CBC of increasing intensity according to a three-stage scheme.   

This method consists in the consistent use of analgesics of increasing strength in combination with adjuvant agents as the intensity of pain increases, and an important principle is to start pharmacotherapy immediately at the first signs of pain.  The fundamental principles of pharmacotherapy of pain are still relevant today:

• taking the drug by mouth,
• taking the drug by the hour, (introducing the next dose of the drug until the previous one ceases to work),
• ascending, i.e. from the maximum dose of a weakly acting opiate to the minimum dose of a strongly acting one,
• the dose of the analgesic is selected individually, depending on the intensity and nature of the pain syndrome, achieving elimination or significant pain relief,
• with attention to detail (as necessary, the appointment of symptomatic agents, monitoring of analgesic therapy with an assessment of its effect and correction of treatment.)

Medications should be prescribed to patients according to the schedule "by the hour", taking into account the duration of single doses, the characteristics of the main and side effects, so that the analgesia is not interrupted and the patient does not experience any unpleasant sensations.

Rational and adequate analgesic treatment with the use of highly effective non-invasive (oral administration, rectal candles, dermal patches) medicines can significantly improve the quality of life of incurable cancer patients.

Oncologist of GUZ "LOOD"

Gupalova T. V.