Abdominal pain is a pathology of the internal and external organs of the abdominal cavity caused by a variety of factors and manifests as pain in the abdomen. According to the pathogenesis, it includes visceral abdominal pain, somatic abdominal pain and sensorimotor abdominal pain. There are also two major types of abdominal pain: acute and chronic. Tumor-induced abdominal pain is also clinically common and complex, and it is mostly chronic. Familiarity with pain caused by tumor is meaningful for the diagnosis of tumor, treatment of pain and improvement of patient’s quality of life. (1) Acute abdominal pain caused by tumor Tumor is a chronic disease and most of the abdominal pain caused is chronic abdominal pain, but the following conditions may also cause acute abdominal pain. Rupture of cancer: what can be seen clinically is liver rupture caused by advanced stage of liver cancer, patients can have sudden abdominal pain, often accompanied by symptoms of hemorrhagic shock. Acute obstruction caused by tumor: common is acute abdominal pain caused by sudden intestinal obstruction of advanced colorectal cancer. (2) Chronic abdominal pain caused by tumors Chronic abdominal pain caused by tumors is very common in clinical practice, mostly caused by intra-abdominal tumors, which can be divided into: gastrointestinal tumors: cardia cancer, gastric cancer, gastric lymphoma, colon cancer, small intestine tumors. Liver, biliary and pancreatic tumors: primary or secondary hepatocellular carcinoma, gallbladder cancer, bile duct cancer, pancreatic cancer, etc. Peritoneal and mesenteric tumors: peritoneal cancer, retroperitoneal tumors, mesenteric tumors. Genitourinary tumors: kidney cancer, bladder cancer, cervical cancer, ovarian cancer, etc. In medicine, cancer abdominal pain includes general abdominal pain and hypochondriac pain. Cancer pain is mainly mixed with deficiency and reality, among which phlegm, dampness, qi and blood internal obstruction are common. Clinical manifestations (a) Symptoms of abdominal pain Location of abdominal pain: The location of abdominal pain often indicates the location of the tumor, such as upper abdominal pain in gastric cancer, left upper abdominal pain in pancreatic cancer, and mid-abdominal pain in colon cancer. The location of some tumor visceral pain is more ambiguous, so it is more accurate to check the site of pressure pain than the patient’s complaint. Abdominal pain: Most of the abdominal pain caused by tumor is slow in onset, gradually worsens and lasts longer, and the effect of general painkiller is poor. If sudden abdominal pain occurs, pay attention to the occurrence of tumor rupture or obstruction. Degree of abdominal pain: Early stage of tumor usually does not cause abdominal pain, but late stage patients can have abdominal pain, which is insidious in origin, light at the beginning and progressively aggravated, and heavy in late stage of cancer. Rhythm of abdominal pain: abdominal pain caused by tumor, in general, abdominal pain in the early stage of the disease is not obvious or mild abdominal pain, and painkillers can receive certain effect. With the aggravation of the disease, especially at the advanced stage of cancer, abdominal pain often increases and is continuous. (2) Accompanying symptoms Different tumors often have different accompanying symptoms in addition to abdominal pain. For example, gallbladder cancer is often accompanied by low fever, stomach cancer is often accompanied by vomiting, colon cancer is often accompanied by diarrhea and abdominal distension, pancreatic cancer is accompanied by jaundice, kidney cancer and bladder cancer are accompanied by hematuria and so on. According to traditional Chinese medicine, “pain is caused by lack of circulation”, whatever the cause is, the pain can be caused by unfavorable qi flow in the internal organs, poor qi and blood flow, and obstruction of the flow of meridians. Cancer abdominal pain can be divided into: deficiency cold in the middle organs: abdominal pain is prolonged, stopping at times, preferring heat to cold, and preferring to press when in pain. Dampness and turbidity obstruction: abdominal distension and pain, with streaks of pain gathering at times, aggravated on time. Qi stagnation and blood stasis: distension and pain in the thorax and hypochondrium, with pain as sharp as needles. Insufficient Yin and Blood: vague pain in the abdomen, with constant pain, aggravated by exertion. Diagnosis and differential diagnosis Abdominal pain caused by tumor is a common clinical symptom, and its diagnosis requires detailed history taking, comprehensive physical examination, necessary laboratory tests and special examinations, and comprehensive analysis, with a view to obtaining a correct diagnosis. (A) Medical history Any history of tumor, if any, should be carefully inquired about the treatment, current disease progress, any recurrence and metastasis. Carefully inquire about the time of abdominal pain, the process of development, whether there is any cause, the nature and degree of abdominal pain, the localization of abdominal pain, and whether there are any accompanying symptoms of abdominal pain, etc. (2) Physical examination: In addition to general body examination, attention should be paid to whether there is jaundice of skin, whether superficial lymph nodes are enlarged, rectal finger examination, etc., all of which have important reference value and should not be missed. Abdominal examination: For abdominal pain caused by tumor or abdominal pain suspected to be caused by tumor, abdominal signs are the focus of examination. First of all, attention should be paid to observe whether the abdomen is elevated, whether there is bowel shape, whether there is whole abdominal pressure pain or local pressure pain, and whether there is muscle tension or rebound pain. Localized tenderness is often indicative of the location of the lesion, with special attention to the painful area and the surrounding abdominal masses that are not palpable. A hard mass with no obvious pressure pain and well-defined borders suggests the possibility of tumor. If lower abdominal and pelvic tumors are suspected, rectal finger examination and palpation of the right sunken fossa are often required. (iii) Laboratory examination Routine examination of blood, urine and feces: the increase of total blood leukocytes and neutrophils can often distinguish whether the abdominal pain is caused by inflammation, and the presence of a large number of red blood cells in urine can help the diagnosis of abdominal pain caused by kidney and bladder tumors. Detection of tumor markers: In clinical abdominal pain suspected to be caused by tumors, the detection of tumor markers often provides useful help in the diagnosis of tumors. For example, in upper abdominal pain, if imaging is suspected to be caused by liver tumor, elevated AFP can often confirm the diagnosis of hepatocellular carcinoma. If CEA is elevated in patients with mid-abdominal or left-right abdominal pain, it may indicate the possibility of colorectal cancer, and further examination can often confirm the diagnosis, etc. Examination of abdominal puncture fluid: When abdominal pain is suspected to be caused by tumor but the diagnosis is not clear, abdominal puncture examination must be done when abdominal fluid is found, and the puncture fluid is sent for routine, biochemical and pathological examination, the latter can give a clear diagnosis of suspected tumor. （X-ray examination: barium meal X-ray or barium enema examination is the most commonly used examination method to detect stomach and intestinal tumor, which is mostly used in primary hospitals. Only when intestinal obstruction is suspected, barium meal angiography is contraindicated. Endoscopic examination: When gastrointestinal cancer, colorectal cancer or gastrointestinal tract occupancy is suspected on X-ray, gastroscopy or fiberoptic colonoscopy should be performed in time and pathological biopsy should be taken to confirm the diagnosis. Ultrasound and CT examination: they play an important role in the diagnosis of suspected hepatic, biliary and pancreatic tumors, and if necessary, liver puncture should be performed based on ultrasound examination to establish the diagnosis of hepatocellular carcinoma. （There are many non-tumor diseases that cause abdominal pain, the common ones are: (1) acute gastroenteritis, acute appendicitis, cholecystitis, acute pancreatitis. (2) ulcer disease: common gastric and duodenal ulcers, mostly in middle age, with upper abdominal pain, and the diagnosis can be established by barium meal examination and gastroscopy. The rupture of abdominal organs can be confirmed by the accumulation of blood from abdominal puncture, and the implementation of ultrasound, CT and gynecological examination can help in the differential diagnosis. (1) Acute abdominal pain caused by tumor: Acute abdominal pain caused by tumor is not common in clinical practice, mainly caused by rupture of liver cancer in patients with advanced liver cancer, with sudden onset and continuous severe pain involving the whole abdomen, often accompanied by shock. There are often signs of accumulation of blood in the abdominal cavity and blood in the abdominal puncture. (2) Chronic abdominal pain caused by tumor: most of the abdominal pain caused by tumor is chronic abdominal pain, which is caused by rapid growth of tumor, resulting in elongation and tension of peritoneum of internal organs or abdominal pain caused by infiltration of cancer and compression of nerves. The abdominal pain is insidious in origin, progressively aggravated and wasting. The common ones are stomach cancer, colorectal cancer, small intestine tumor, etc. X-ray gastrointestinal and barium enema examinations and endoscopy can often confirm the diagnosis. For liver cancer, gallbladder cancer, bile duct cancer, pancreatic cancer, etc., ultrasound and CT examination, together with the determination of tumor markers, are generally not difficult to diagnose, and if necessary, abdominal mass puncture can be performed under ultrasound guidance, and pathological biopsy can be taken to confirm the diagnosis. The cause of abdominal pain should be identified first, and the diagnosis should be clear, and treatment should be carried out for the cause. For acute abdominal pain caused by tumor, such as those caused by primary or secondary rupture of hepatocellular carcinoma, it is an acute abdominal pain, which needs to be treated urgently with blood and fluid transfusion in time, and those in shock should be rescued from shock and treated with surgery as soon as possible. For chronic abdominal pain caused by tumor, firstly, identify the cause, determine the diagnosis, clarify the stage of the disease, and formulate a treatment plan for the primary tumor, such as surgery, or non-surgical chemotherapy, radiotherapy, biological therapy, etc., and carry out treatment as soon as possible. For chronic abdominal pain caused by tumor, general treatment of abdominal pain should also be carried out, including fluid infusion, correction of water, electrolyte and acid-base balance disorders, and fasting if necessary. If there are symptoms of shock, prevent the occurrence of shock; if shock has occurred, actively rescue shock. If there is gastrointestinal obstruction, perform gastrointestinal decompression. According to the condition, apply broad-spectrum antibiotics to prevent and control infection as appropriate. According to the degree of abdominal pain, use antispasmodic analgesic; for patients with severe abdominal pain and clear diagnosis of tumor where general analgesic is ineffective, apply narcotic analgesic. Chinese medicine treatment 1, dampness and turbidity obstruction: abdominal distension or pain, sometimes there are strips and cords gathered, the distension and pain increase on time, dullness, constipation, abdominal stuffiness, heavy head and body sleepiness, nausea and vomiting, body and eyes are yellow, greasy coating, smooth pulse. Treatment: Strengthening the spleen, relieving dampness, resolving turbidity and detoxification. In this formula, Atractylodes macrocephala, Poria, Poria and Zeligia are used to strengthen the spleen and promote dampness, while Yin Chen clears heat and promotes dampness. For liver cancer, add Xiang Xiang, Chuan Dongzi and Yuan Hu; for those with spleen yang incompetence and obvious cold-dampness obstruction, add Gui Zhi and Gan Jiang to warm cold-dampness; for obvious damp-heat, add Huo Xiang, Mu Tong, Scutellaria Baicalensis and Coix Seed to clear damp-heat. In advanced stage of gastric cancer, Xiang Sha Liu Jun Zi Tang is the main treatment. 2.Qi stagnation and blood stasis: distension and fullness in the chest, abdominal distension and pain, even pain like needles, refusal to press, accompanied by belching, acid swallowing, poor appetite, aggravated by emotional discomfort, dull complexion, dark tongue or petechiae, thin and astringent pulse. Treatment: Promoting Qi, activating Blood circulation and eliminating blood stasis. In this formula, Wu Ling Li, Red Peony, Radix Angelicae Sinensis, Safflower and Peach kernel are used to invigorate blood circulation and eliminate blood stasis, while Xiang Shen, Wu Yao, Yan Hu Suo, Chuan Xiong and Citrus Aurantium are used to move Qi and invigorate blood circulation; add Gunnera, Bayberry and Sarsaparilla to soften hardness and disperse knots. For liver cancer with obvious distension and pain, add Chai Hu and Shu Huan Tang; for stomach cancer or esophageal cancer with less food and abdominal pain, Tong Yu Tang is the mainstay; for intestinal cancer, Tong Yu Tang is used under the diaphragm; for liver cancer with belching and acid swallowing, Zuo Jin Wan can be used in combination. 3.Deficiency cold in the middle organs: abdominal pain is incessant, preferring warmth and pressure, and abhorring cold, aggravated by fatigue, accompanied by shortage of breath and lazy speech, cold body and limbs, dullness, loose stools, light tongue with thin white coating and sunken pulse. Treatment: Warming the middle and nourishing the deficiency, relieving the pain. Add Astragalus, Poria, Ginseng, Atractylodes, etc. to help benefit the qi and strengthen the spleen; add Cornu Cervi Pantotrichum, Dry Ginger, Sichuan Pepper, Wu Yao, etc. to help dispel cold and regulate qi. In the late stage of gastric cancer, the body constitution decreases, manifesting as less qi and lazy speech and general weakness, so use tonifying and benefitting qi soup; in the late stage of cancer, the deficiency of both qi and blood is reduced by adding ten whole tonic soup. 4.Deficiency of Yin and Blood: vague and continuous pain in the ribs and abdomen. It is aggravated by labor, accompanied by dry throat and dry mouth, irritable heat in the heart, dizziness, red tongue, little coating, and fine pulse. Treatment: Nourishing Yin and nourishing Blood. Remedy: Consistent Decoction with Addition and Reduction. In this formula, Radix Rehmanniae nourishes Blood and nourishes Yin, tonifies Liver and benefits Kidney, Salviae Miltiorrhizae, Radix Angelicae Sinensis, Fructus Lycii benefit Yin, nourish Blood and soften Liver, and Neem detoxify Liver and regulate Qi. For gastric cancer, Sha Shen Mai Men Dong Tang is the mainstay; for esophageal cancer, Wu Ju An Zhong Tang is the mainstay; for intestinal cancer with constipation, Rhizoma Glycyrrhizae Tang is used to remove heat and store fluid.