Cancer Pain

Cancer has been a major health issue causing significant distress and suffering since the beginning of humankind, often accompanied by a feeling of helplessness and psychological depression. Pain in this disease, which places great importance on early diagnosis and treatment, is sometimes the primary reason a patient seeks medical care. However, more often, it's a challenge that the patient has to deal with throughout the course of the illness. This pain can reach levels that interfere with treatment and daily activities.

A multidisciplinary approach—one of the most critical elements of pain management, involving collaboration among specialists from various medical disciplines (like algology, oncology, surgery, radiology, psychiatry, psychology, and family medicine)—is crucial in cancer treatment. This way, while the disease treatment continues, it's possible to elevate the patient's quality of life.

The pain experienced in various types of cancers stems from different causes, depending on the type of cancer, its stage, and the patient's pain threshold. The intensity of pain in cancer typically varies from moderate to severe. Each patient's pain is unique, necessitating an individualized treatment plan.

The causes of pain in cancer are primarily attributed to:

•  Related to the tumor (77%)

• Related to treatment modalities applied during cancer treatment, such as surgery, chemotherapy, radiotherapy (19%)

• Non-cancer-related causes (4%)

Pain in cancer can develop due to:

• Circulatory disturbances caused by blockage in blood vessels

• Bone fractures due to metastasis

• Infections

• Inflammation

• Compression of the tumor on the nerves

• Obstruction of hollow organs (like intestines) or various channels (like bile ducts)

Frequency of Pain in Cancer

Studies have shown that 90% of patients with advanced cancer and 30% of all cancer patients, regardless of stage, suffer from0 pain. 50% of patients suffering from cancer pain do not receive adequate pain treatment.

The most common pain originating from cancer is bone metastasis pain. 60-80% of cancer patients with bone metastasis suffer from pain. The second most common cancer pain is due to tumors pressing on nerves or internal organs. Tumors adjacent to nerve tissues are typically the most painful. The third most common cancer-related pain is associated with chemotherapy, radiotherapy, or surgical interventions.

Cancer pain can occur in different areas of the body. In one study, more than 80% of patients experienced pain in two different regions, and more than 30% in three different areas.

Chronic pain is a condition that physicians should effectively treat. This type of pain affects various aspects of a person's life, altering their personality, capabilities, and quality of life.

Chronic pain is of two types: continuous and breakthrough pain. Breakthrough pain is short-lived, severe pain flare-ups that occur despite regular painkiller intake. It usually starts suddenly and lasts a few minutes to a few hours. Many patients experience multiple episodes of breakthrough pain throughout the day.

Breakthrough pain can result from cancer or cancer treatment or can occur during specific activities like walking, dressing, or coughing. However, sometimes it can appear unexpectedly without an apparent cause. Breakthrough pain is typically treated with fast-acting, potent drugs.

Pain Classification in Cancer Patients

Acute cancer pain

 Arise due to the rapid proliferation of cancer cells invading healthy tissues. This can be observed both at the onset and advanced stages of the disease. Pain is an early symptom in breast, prostate, ovarian, and rectal cancers. In advanced stages, for instance, acute pain can emerge due to tumor-induced vertebral and hip fractures or intestinal blockage caused by the tumor. Acute pain can also result from cancer treatments like surgery, radiotherapy, and chemotherapy.

Chronic cancer pain

 The mechanisms leading to pain include blockages of lymphatic and vascular paths and tissue damage (swelling and inflammatory reactions in healthy tissues). 75% of patients experience chronic pain. The types of chronic pain are:

Pain due to bone tissue invasion

Chronic pain frequently arise from bone invasion by cancer cells, commonly seen in breast, prostate, thyroid, lung, and kidney tumors. The pain is continuous, increasing during the night and with movement. Patients describe it as dull, throbbing, or deep, stabbing pain. Muscle contractions can also cause spasmodic, cramping pain. Bone scintigraphy is invaluable for early diagnosis.

Pain due to nerve and spinal cord invasion

Treatment for this type of pain, caused by nerve tissue invasion by cancer cells, is challenging. The pain is continuous, burning, or intermittent stabbing. Symptoms like numbness, tingling, and muscle weakness appear in the affected area. Invasions of the spinal cord can lead to weakness in the arms and legs, paralysis, and incontinence.

Pain due to the invasion of hollow or solid organs' paths: Severe pain occur when hollow organs like the stomach or intestines or the bile ducts in the liver get obstructed by cancer cells.