How is Pain Generated in Benign and Malignant Cancer?

Cancer pain may be acute or chronic depending on duration. Acute pain lasting 3 to 6 month is often secondary to benign cancer. Similarly chronic pain lasting more than 6 months is secondary to malignant cancer.

Benign cancer tissue enlarges very slowly in size, but do not infiltrate into surrounding tissue. Benign tumor is encapsulated within fibrous capsule. Benign tumor does not metastasized. Benign tumor are non cancerous.

Benign tumor is covered by thick fibrous tissue, which prevents local infiltration in surrounding tissue. Non-cancerous tumor does not invade blood vessels and thus spread to different organs. Benign tumor mass very much stays as a local mass of tumor cells.

Metastasis is a spread of tumor from one organ to an adjacent organ by local infiltration or distant organ by spread through blood vessels. Metastasis or spread to other organs through blood or lymphatic is not commonly observed with benign cancer. Tumor is known as cancer when tumor invades into adjacent organ or spreads into distant organ.

Encapsulated benign tumor enlarges in size resulting in severe pressure on surrounding organ and tissue. Pressure often causes ischemia (lack of blood supply) of surrounding tissue resulting in severe throbbing pain. Benign tumor may pinch the nerve located around the tumor mass causing severe burning pain.

Ischemic is reduction or lack of blood supply to normal tissue. Ischemic tissue may end up necrotic and lead to symptoms such as nausea, vomiting, dizziness and bleeding. Some time massive size of tumor can cause obstruction of organs followed by constipation and retention of urine or stool.

Benign tumor causes delayed pain. Pain is often associated with enlarged tumor mass. Benign tumor is often diagnosed secondary to pressure symptoms like nausea, vomiting, constipation and soft tissue mass felt in abdomen or extremities. About 15 to 30% of patients diagnosed of benign tumor suffer with acute pain at the time of diagnosis.

Malignant cancer pain is chronic (more than 6 months), widespread and intense. Malignant cancers spread to surrounding and distant tissues as well as organs. Local cancer tissue spread involves increase of size as well as penetration and infiltration of surrounding normal tissue or organs causing tissue necrosis and irritation of the surrounding nerve. Penetration of cancer tissue in to blood vessel causes ischemia by obstruction to flow and bleeding by tear or rupture of blood vessels. Tear or rupture of blood vessels occasionally follows life threatening major or minor bleeding. Cancer tissue may spread to liver, brain and lungs through blood vessels and lymphatics. Tumor tissue mass is called metastasis when spread into other distant organs.

Various studies have suggested 19 to 49% of patient had pain as early symptoms. Pain could be predominant symptom in metastatic cancer than benign cancer. Pain symptom that occurs in over 60% of cancer patients may have progressed beyond primary location. Chronic pain is as high as 90% in the advanced cancer patients.

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Also Read:

• Does Cancer Pain Hurt & How Long Does Cancer Pain Last?
• Treatment Plan for Cancer Pain
• Cancer Pain Management: Chemotherapy, Radiation, Surgery, Interventional Pain Therapy
• Malignant Cancer Pain: Everything You Need to Know!
• Cancer Pain: Causes, Symptoms, Treatment, Management