Elderly pancreatic cancer

　　There is no definitive conclusion about the etiology of elderly pancreatic cancer. Currently, there are mainly two theories, namely the action of carcinogens in the environment on the pancreas and the development of cancer on the basis of chronic pancreatitis.
　　1. The distribution of pancreatic cancer sites:① Pancreatic head cancer, which is more common, accounting for more than 2/3 of pancreatic cancer. ② Pancreatic body and tail cancer, accounting for about 1/4 of pancreatic cancer. ③ Total pancreatic cancer, accounting for about 1/20 of pancreatic cancer.
　　2. The histological classification of pancreatic cancer:① Ductal adenocarcinoma is the most common, accounting for about 90% of pancreatic cancer. Under the microscope, it mainly shows duct-like structures of varying degrees of differentiation, accompanied by abundant fibrous stroma. Due to the hardness of the tumor and unclear boundaries, most ductal carcinomas have a positive reaction of serum CEA and CA19-9. Molecular biological technology detection found that all 12 codons of the Ki-ras oncogene in pancreatic cancer have point mutations, accounting for 75% to 100%. In invasive carcinoma tissue, C-erbB2 oncogene expression can be found. ② Acinar cell carcinoma. ③ Other types such as pleomorphic adenocarcinoma, cilium cell adenocarcinoma, mucinous epidermoid carcinoma, squamous cell carcinoma, adenosquamous carcinoma, papillary cystadenocarcinoma, and islet cell carcinoma are less common.

　　The main complications of elderly pancreatic cancer include obstructive jaundice, liver, lung, and bone metastasis. Obstructive jaundice is caused by obstruction of the extrahepatic bile duct or intrahepatic bile duct, which is called extrahepatic obstructive jaundice in the former and intrahepatic obstructive jaundice in the latter. Intrahepatic obstruction of obstructive jaundice is generally rare >171umol/L, while extrahepatic obstruction of obstructive jaundice can reach 256.2-513umol/L, and there is little fluctuation; AKP in obstructive jaundice is usually higher, and malignant obstruction is more obvious; ALT in obstructive jaundice is generally 5000U; when obstructive jaundice is severe, the excretion of coproporphyrin is significantly reduced, and feces may become clay-colored.

　　The elderly with pancreatic cancer mainly show the following symptoms:

　　Abdominal pain

　　More than half of the patients have abdominal pain, which is initially mild and gradually worsens. Pancreatic cancer patients may experience persistent or intermittent upper abdominal pain due to the tumor causing the pancreas to enlarge, compressing the pancreatic duct, leading to obstruction, dilation, torsion, and increased pressure. Sometimes, pancreatitis may also occur simultaneously, causing visceral neuralgia. In the early stage of the disease, the lesions often present as a wide range in the middle and upper abdomen, which is not easy to locate and has a relatively vague nature, such as fullness, discomfort, dull pain, or hidden pain. The less common cases are paroxysmal severe upper abdominal pain that progresses, which is more common in early pancreatic head cancer with obstruction of the pancreatic and biliary ducts.

　　Weight loss

　　Pancreatic cancer causes significant weight loss, with a noticeable loss of weight appearing in the short term after onset, which can reach more than 15kg. It is accompanied by symptoms such as fatigue and weakness. Some patients first show progressive weight loss, with the cause of weight loss due to loss of appetite, reduced food intake, or even if they have appetite, they are unwilling to eat due to discomfort in the upper abdomen or abdominal pain induced by eating. In addition, poor exocrine function of the pancreas or obstruction of pancreatic juice flowing out through the pancreatic duct affects digestion and absorption, which is also related to a certain extent.

　　Three, jaundice

　　Jaundice is an important symptom of pancreatic cancer, especially pancreatic head cancer. Jaundice is obstructive due to invasion or compression of the lower end of the bile duct, and jaundice is progressive, although there may be slight fluctuations, it is impossible to completely disappear. In the early stage, it is related to the regression of peripancreatic inflammation around the ampulla, and in the late stage, it is due to the ulceration and swelling of the tumor invading the lower end of the bile duct. The body and tail cancer appear jaundice only when it involves the head of the pancreas, and some patients with pancreatic cancer have jaundice in the late stage due to liver metastasis.

　　About half of the patients can feel an enlarged gallbladder, which is related to the obstruction of the lower segment of the bile duct. In clinical practice, obstructive jaundice with enlargement of the gallbladder without tenderness is called Courvoisier sign, which has diagnostic significance for pancreatic head cancer, but the positive rate is not high. If there is chronic cholecystitis, the gallbladder may not be enlarged, so the absence of painless enlargement of the gallbladder cannot exclude pancreatic head cancer.

　　Four, abdominal mass

　　Most abdominal masses are signs of late stage, with irregular shape, uneven size, firm consistency, and can have obvious tenderness. Abdominal masses are relatively more common in body and tail cancer of the pancreas.

　　Five, other gastrointestinal symptoms

　　1. Indigestion symptoms

　　In pancreatic cancer, especially in pancreatic cancer occurring in the main pancreatic duct or close to the main pancreatic duct, the pancreatic duct is blocked, causing obstructive chronic pancreatitis, leading to malfunction of the exocrine function of the pancreas; or the lower end of the bile duct and the pancreatic duct are blocked by the tumor, bile and pancreatic juice cannot enter the duodenum, thus causing symptoms of indigestion, a few patients may have obstructive vomiting, about 10% of patients have severe constipation, and about 15% of patients have diarrhea; steatorrhea is a late manifestation, which is a unique symptom of malfunction of the exocrine function of the pancreas, but it is rare.

　　2. Upper gastrointestinal hemorrhage

　　About 10%, mainly due to the invasion of adjacent hollow organs such as the duodenum or stomach, causing erosion or ulceration, and it can also be caused by the infiltration of the tumor into the common bile duct or ampulla, causing erosion or ulceration at that place, resulting in acute or chronic hemorrhage. The body and tail of the pancreas cancer compress the splenic vein or portal vein or form an embolism, secondary to portal hypertension, leading to esophageal varices and gastric fundus varices rupture and massive hemorrhage, which is occasionally seen.

　　Symptomatic diabetes

　　In some patients, the initial manifestation of the disease is the symptoms of diabetes; it can also be manifested as the aggravation of the disease in patients with long-term diabetes, so if diabetic patients have persistent abdominal pain, or elderly patients suddenly develop diabetes, or patients with diabetes have sudden aggravation of the disease recently, they should be alert to the possibility of pancreatic cancer.

　　Vascular thrombotic diseases

　　Approximately 10% to 20% of pancreatic cancer patients develop migratory or multiple thrombophlebitis, and this can be the initial symptom. There is a higher chance of thrombophlebitis in the body and tail of the pancreas cancer, and it often occurs in the lower limbs, and it is more likely to occur in well-differentiated adenocarcinoma. Autopsy data show that the incidence of arterial and venous thrombosis accounts for about 25%, especially in iliac and femoral vein thrombosis, but there are no clinical symptoms, and arterial thrombosis is more common in pulmonary arteries, and occasionally in the spleen, kidney, coronary arteries, and cerebral arteries.

　　Eight. Psychiatric symptoms

　　Some pancreatic cancer patients may show symptoms such as anxiety, irritability, depression, and personality changes, and the mechanism of occurrence is still unclear. It may be due to the fact that pancreatic cancer patients often have intractable abdominal pain, insomnia, and inability to eat, which are easy to affect their spirit and emotions.

　　Nine. Acute cholecystitis or cholangitis

　　About 4% of pancreatic cancer patients present with sudden onset of right upper abdominal colic accompanied by fever, jaundice, and acute cholecystitis or acute suppurative cholangitis as the first symptom. This may be due to tumor compression, obstruction of the lower end of the common bile duct, or the presence of stones at the same time.

　　Ten. Abdominal vascular murmur

　　When the tumor compresses the abdominal aorta or splenic artery, a blowing vascular murmur can be heard around the umbilicus or in the upper left abdomen, with an incidence of about 1%. It is generally believed that the appearance of vascular murmur indicates that the lesion has reached an advanced stage.

　　The causes and mechanisms of the occurrence of elderly pancreatic cancer have not been elucidated so far. Epidemiological survey data suggest that the increased incidence may be related to long-term smoking, high-fat and high-animal protein diet, alcoholism, coffee drinking, certain chemical carcinogens, endocrine and metabolic disorders, chronic pancreatic diseases, and genetic factors. It is generally believed that it may be the result of the long-term combined action of multiple factors.

　　1. Diet factors

　　Epidemiological studies show that the incidence of pancreatic cancer is related to the intake of animal fats in the diet. High triglycerides and/or high cholesterol, and low fiber diets may promote or affect the occurrence of pancreatic cancer. The incidence of pancreatic cancer in Japanese people was low several decades ago, but since the 1950s, with the popularization of Western-style diets, the incidence has increased fourfold. After the body takes in high cholesterol diet, some cholesterol is converted into epoxides in the body, which can induce pancreatic cancer. In addition, after consuming a high-fat diet, it can promote the release of a large number of gastrointestinal hormones such as gastrin, cholecystokinin, secretin, and CCK-PZ, which are strong stimulators of pancreatic proliferation. They can cause the proliferation of pancreatic ductal epithelium, metaplasia, and promote cell renewal, and increase the susceptibility of pancreatic tissue to carcinogens. Some nitrosamine compounds may have organ-specific carcinogenicity in the pancreas. In addition, in recent years, it has been found that the risk of developing pancreatic cancer is twice as high for those who drink 1 to 2 cups of coffee a day compared to those who do not drink coffee. If more than 3 cups are consumed daily, the risk increases threefold, suggesting that one or more components in coffee beverages may promote the occurrence of pancreatic cancer.

　　2. Drinking factors

　　The exact relationship between drinking and the incidence of pancreatic cancer is not yet clear. Some people believe that the occurrence of pancreatic cancer is related to the long-term consumption of a large amount of wine. The relative risk of pancreatic cancer for beer drinkers is about twice that of non-beer drinkers. The possible reason is that after alcohol intake, it can continuously stimulate the secretion of active pancreatic cells, causing chronic inflammation of the pancreas, leading to pancreatic damage, or due to the presence of other carcinogenic substances such as nitrosamines in alcohol.

　　3. Smoking Factors

　　Many research data indicate that smoking is closely related to the incidence of pancreatic cancer. The incidence of pancreatic cancer in smokers is 2 to 3 times higher than that in non-smokers, and the average age of onset is 10 or 15 years earlier. The onset may be related to the following factors: ① Certain harmful components or their metabolically active substances in tobacco are absorbed after smoking and excreted through the bile duct, and in some cases, they reflux into the pancreatic duct, stimulating the pancreatic ductal epithelium, and eventually leading to cancer. ② Certain carcinogens in tobacco, such as hydrocarbons and nitrosamines, can be rapidly absorbed from the oral, upper respiratory mucosa, and lung tissue, and excreted through the pancreas. A small amount of nitrosamines in cigarettes can be metabolically activated into diisopropyl nitrosamine active carcinogens. ③ Nicotine in tobacco promotes the release of catecholamines in the body, leading to a significant increase in blood cholesterol levels. In some ways, hyperlipidemia can induce pancreatic cancer, which is particularly evident in heavy smokers who smoke more than 40 cigarettes a day.

　　4. Environmental Factors

　　Most scholars believe that occupational exposure to certain chemical substances may have a carcinogenic effect on the pancreas. Long-term exposure to certain metal soot, gas factory work, asbestos, dry cleaning solvents, and contact with β-naphthylamine, benzidine, methylcholanthrene, N-nitrosomethylamine, acetylaminofluorene, and other chemical agents can significantly increase the incidence of pancreatic cancer. In recent years, it has been found that pancreatic ductal epithelial cells can metabolize certain chemical substances into substances with chemical carcinogenic effects. In addition to secreting a large amount of sodium bicarbonate, pancreatic ductal epithelial cells can also transport liposoluble organic acids and certain chemical carcinogens, increasing the concentration of carcinogens in the acinar cells or adjacent pancreatic ducts, thereby changing the intracellular pH and triggering the development of pancreatic cancer.

　　5. Endocrine Metabolic Factors

　　The relationship between diabetes and pancreatic cancer is not yet clear. It is generally believed that chronic, obstructive pancreatitis and islet fibrosis often accompany pancreatic cancer. Therefore, pancreatitis and diabetes are only symptoms of pancreatic cancer. However, in individuals with hereditary, insulin-dependent diabetes, especially in female diabetic patients, the incidence of pancreatic cancer is greatly increased. Conditions such as multiple abortions, post-ovary surgery, or endometrial hyperplasia can cause endocrine dysfunction and an increased incidence of pancreatic cancer, suggesting that sex hormones may play a certain role in the pathogenesis of pancreatic cancer.

　　6. Genetic Factors

　　There seems to be a certain relationship between genetic factors and the incidence of pancreatic cancer. Wyder et al. reported that the incidence of pancreatic cancer in blacks is higher than that in whites, and the incidence in Jewish populations in the United States is also higher than that in other populations. It was reported that among five siblings, three developed pancreatic cancer at the ages of 54.48 or 55, and all were confirmed by surgery.

　　In addition to clinical manifestations, the following examination methods can be selected for the diagnosis of elderly pancreatic cancer.

　　One, Tumor Marker Detection

　　1. Carcinoembryonic antigen (CEA)

　　CEA is a tumor-associated antigen extracted from colon adenocarcinoma and is a tumor embryonic antigen, which is a glycoprotein. It can increase in digestive tract tumors such as colon cancer, pancreatic cancer, gastric cancer, lung cancer, etc. The sensitivity and specificity of CEA for diagnosing pancreatic cancer are both low, with only 30% of advanced pancreatic cancer patients showing elevated serum CEA. Some reports indicate that the sensitivity and specificity of CEA are 35% to 51% and 50% to 80% respectively. Due to the possibility of false positives in both normal people and patients with chronic pancreatitis, the elevation of serum CEA level has only a reference value for the diagnosis of pancreatic cancer. It is reported that measuring CEA in pancreatic juice, combined with cytological examination of pancreatic juice, can increase the sensitivity of diagnosis to 86%. CEA cannot be used as a screening test for asymptomatic populations, nor can it be used as a method for early diagnosis of pancreatic cancer.

　　2. Carbohydrate antigen determinant CA19-9

　　It is a glycoprotein extracted from colon cancer cell lines and has high sensitivity and relative specificity for pancreatic cancer. The normal serum CA19-9 value in humans is 8.4 ± 4 U/ml, and 37 U/ml is the critical value. The diagnostic sensitivity for pancreatic cancer reaches 79%, while it is only 18% for colon cancer, and none of the patients with pancreatitis show an increase. It helps in differentiation. Recently, the application of immunoperoxidase staining method for detecting CA19-9 has been introduced, which can reach an accuracy of 86% for diagnosing pancreatic cancer. The content of CA19-9 is positively correlated with the size of the tumor, and those with low levels have a higher possibility of surgical resection. After tumor resection, CA19-9 levels significantly decrease to normal, indicating a better prognosis.

　　3. Pancreatic cancer embryonic antigen (POA)

　　POA is an antigen found in normal fetal pancreatic tissue and pancreatic cancer cells. The normal value is 4.0 ± 1.4 U/ml, and a value above 7.0 U/ml is considered positive. Literature reports that the incidence of elevated POA in patients with pancreatic cancer is 73%, while the positive rates in gastric cancer and colon cancer are 49% and 33% respectively. The sensitivity and specificity of POA for diagnosing pancreatic cancer are 73% and 68% respectively, but about 10% of cases of pancreatitis can show false positives. It has certain reference value for the diagnosis of pancreatic cancer, but the specificity is not high, so its wide application is still limited.

　　4. Pancreatic cancer-related antigen (PEAA) and pancreatic-specific antigen (PSA)

　　PEAA is a glycoprotein isolated from the ascites of pancreatic cancer patients. The normal upper limit of PEAA in serum is 16.2 ng/L, and 53% of patients with pancreatic cancer have positive PCAA. Among stage I patients, the positive rate is 50%, but the positive rates in patients with chronic pancreatitis and cholelithiasis are also as high as 50% and 38% respectively, indicating that the specificity of PCAA for diagnosing pancreatic cancer is poor. PSA is a single-chain protein extracted from normal human pancreas and is an acidic glycoprotein. The normal level in humans is 8.2 μg/L, and a level above 21.5 μg/L is considered positive. 66% of patients with pancreatic cancer have positive serum PSA, among whom 60% of stage I patients are positive. The positive rates in patients with benign pancreatic diseases and cholelithiasis are 25% and 38% respectively. The sensitivity and specificity of PSA and PCAA combined detection for pancreatic cancer are significantly higher than those of single detection, reaching 90% and 85% respectively.

　　The levels of carbohydrate antigen-199 (CA-199), pancreatic embryonic antigen (PEA), and tumor-specific growth factor (TSGF) were detected by ELISA, and the colorimetric method was used to detect TSGF. The contents were all significantly increased, with positive rates of 85.4%, 87.5%, and 83.3%, respectively. The combined detection of the three has a positive rate of 100% for the diagnosis of pancreatic cancer. The dynamic detection of CA-199, PEA, and TSGF is an important indicator for the diagnosis of pancreatic cancer, the observation of the efficacy of pancreatic cancer, and the judgment of prognosis.

　　2. Other laboratory tests

　　1. CCK-PZ and secretin test

　　After intravenous infusion of CCK-PZ and secretin, pancreatic juice is collected from the duodenum. The normal value is that the flow rate after the injection of secretin is >90ml at 80min, the highest concentration of bicarbonate is >80mmol/L, and the total excretion of amylase after the injection of CCK-PZ is >7500 SomogyiU/80min. Pancreatic cancer patients mainly have significantly reduced enzyme values and bicarbonate concentrations.

　　2. BT-PABA test

　　The oral synthetic polypeptide BT-PABA test is used to determine the secretion function of trypsinogen, with a normal value of 63.52±10.53%. If it is below 30%, it is definitely indicative of low pancreatic secretion function, which is seen in pancreatic cancer and chronic pancreatitis.

　　3. Serum ribonuclease

　　Some reports show that 90% of pancreatic cancer patients have elevated serum ribonuclease levels, >250U/ml (normal value

　　4. Lactoferrin

　　LF is a glycoprotein combined with iron, which can be detected in various exocrine fluids such as milk, pancreatic juice, saliva, bile, bronchial secretions, and special granules of neutrophils. Detection of LF in pancreatic juice helps to differentiate pancreatic cancer from chronic pancreatitis.

　　In recent years, due to the rapid development of imaging examination technology and the progress of experimental diagnostic methods, the diagnostic level of pancreatic cancer has been improved, but the detection rate of early pancreatic cancer (tumor diameter ≤ 2cm, capsule not invaded, no metastasis) is still very low, and it is necessary to continue to explore.

　　3. X-ray examination

　　Low-tension duodenal angiography is significant for the diagnosis of pancreatic cancer, as pancreatic cancer can affect adjacent hollow organs, causing them to shift or be invaded, the most common being the

　　2. Retrograde pancreatic and bile duct造影 (ERCP)

　　By inserting a catheter into the ampulla opening through the duodenoscope to perform ERCP, the diagnostic rate for pancreatic cancer is about 85% to 90%, which is higher than that of B-ultrasonography or CT. It can detect pancreatic cancer earlier, especially for those with lower bile duct and pancreatic duct obstruction, which has significant clinical significance. The ERCP manifestations can be divided into obstruction type, local stenosis type, progressive stenosis type, and abnormal branch type, etc. The main pancreatic duct and common bile duct show double duct sign, etc. The advantages are that it can observe whether the pancreatic head lesion infiltrates the duodenal papilla and the morphological changes of the pancreatic duct and bile duct. It is the most valuable method to show the pancreatic duct.

　　3. Selective celiac artery angiography

　　By inserting a catheter into the celiac artery, superior mesenteric artery, and its branches through the abdominal aorta, selective angiography is performed. The accuracy rate of selective angiography is about 90%. In pancreatic cancer, the main manifestations are variations in the morphology of intra-abdominal or peripancreatic arteries and veins, including serrated changes in the vascular wall, narrowing, angular changes, namely displacement, interruption, and obstruction, etc.

　　4. Percutaneous liver puncture cholangiography (PTC)

　　It can show the location, degree of bile duct obstruction, and differentiate it from stones. For example, if there is dilation of the intrahepatic bile ducts, the success rate of puncture under the guidance of B-ultrasonography is over 90%.

　　IV. CT examination and MRI imaging

　　1. CT examination

　　It is a non-invasive imaging technique that can observe the position, contour, and tumor manifestations of the pancreas more clearly. CT has a diagnostic rate for pancreatic cancer of about 75% to 88%. The main manifestations of pancreatic cancer include local mass, partial or abnormal enlargement of the pancreatic shape, disappearance of the fat layer around the pancreas, tumor, and edema of the body and tail adjacent to the pancreatic head. Due to necrosis of the tumor or obstruction of the pancreatic duct, secondary cystic dilation occurs, presenting as focal areas of reduced density.

　　2. MRI imaging

　　The MRI of pancreatic cancer shows irregular T1 values, with higher T1 values at the center of the tumor. If there is bile duct obstruction at the same time, it is considered a specific manifestation of pancreatic cancer, which is significant for distinguishing between benign and malignant tumors.

　　3. MRCP

　　It has characteristics such as non-invasiveness, no trauma, no serious complications, short examination time, no need for contrast agent injection, no X-ray damage, and can clearly show the condition of bile ducts and pancreatic ducts. Its diagnostic rate for pancreatic cancer is similar to that of ERCP.

　　V. Ultrasonography

　　1. B-ultrasonography

　　It can be understood whether there is dilation of the extrahepatic bile ducts, whether there are tumors at the lower end of the pancreatic head or common bile duct, the location of extrahepatic bile duct obstruction, the nature, and the degree of bile duct dilation. The ultrasound image of pancreatic cancer shows localized enlargement or lobular changes of the pancreas; the edges are unclear, and the echo is reduced or disappeared.

　　2. Endoscopic ultrasound examination

　　For the diagnosis of pancreatic cancer, including early-stage pancreatic cancer, it has great value and can make a certain diagnosis on the possibility of surgical resection. The endoscopic ultrasound examination of pancreatic cancer is manifested as:

　　(1) Hyperechoic solid mass, internally visible irregular spots, presenting as circular or nodular, with rough edges of the mass. The typical lesion has a flame-like outer contour.

　　(2) The infiltration of pancreatic cancer into surrounding large blood vessels is manifested as rough edges of blood vessels and compression by the tumor, and so on.

　　Sixth, laparoscopic examination

　　Under laparoscopic direct vision, the normal surface of the pancreas is yellowish-white. Due to the special anatomical position of pancreatic head cancer, laparoscopic examination can only be diagnosed based on indirect signs, which are manifested as significant gallbladder enlargement, green liver, large gastric窦side irregular mass-like protuberance and deformation, varices of the right gastroepiploic artery and superior pancreaticoduodenal artery, and changes such as liver and peritoneal metastasis. The direct signs of pancreatic body and tail cancer are pancreatic masses with irregularly proliferating small blood vessels accompanied by vascular interruption, narrowing, and hard texture. The indirect signs include varices of the coronary vein of the stomach and the great omentum vein of the stomach, disordered omental blood vessels, green liver, and enlarged gallbladder, and so on.

　　Seventh, pancreatic biopsy and cytological examination

　　Fine needle aspiration biopsy (FNA) before or during surgery is used for diagnosing pancreatic cancer and obtaining pancreatic cells. The methods include:

　　1. Direct puncture of the pancreas from the pancreatic duct and duodenal wall through the duodenoscope;

　　2. Under the guidance of ultrasound, CT, or angiography, percutaneous fine needle puncture of pancreatic tissue is performed;

　　3. Under direct vision during surgery, Kim performed FNA on 30 patients with pancreatic lesions, with an accuracy rate of 80%, specificity of 100%, sensitivity of 79%, positive predictive value of 100%, which is one of the very effective methods for diagnosing pancreatic cancer.

　　Elderly patients with pancreatic cancer have high dietary requirements, especially after postoperative radiotherapy and chemotherapy, it is necessary to pay more attention to reasonable and planned nutritional supplementation.

　　Firstly, suitable diet for elderly patients with pancreatic cancer

　　1. It is recommended to have light, easy-to-digest, low-fat diet, eat less and more frequently, such as lotus root starch porridge, rice porridge, tomato soup, egg soup, de-haired mung bean soup, vegetable juice, thin noodle soup, pork liver soup, soy milk, and so on.

　　2. It is recommended to eat foods that enhance immunity and have anti-pancreatic cancer effects, such as turtle, tortoise, sturgeon, sharks, mackerel, herring, snakes, yam, green beans, mushrooms, and jujube.

　　3. It is recommended to eat foods with anti-cancer and analgesic effects, such as sharks, sea horses, perch, walnuts, malt, chives, and bitter melon.

　　4. It is recommended to eat anti-infection foods: crucian carp, knife fish, turtle, wild duck meat, water snake, mung bean sprouts, olives, black plum, mung beans, red beans, bitter melon, and so on.

　　5. It is recommended to eat grains (rice, flour) and lean pork, chicken, fish, shrimp, eggs, soy products, vegetables, and fruits, etc.

　　Secondly, dietary taboos for elderly patients with pancreatic cancer

　　1. Avoid greasy and high animal fat foods, such as lard, mutton, meat floss, shellfish, peanuts, walnuts, sesame seeds, oil-soaked pastries, and so on.

　　2. Avoid overeating and overeating, and also control protein and sugar appropriately.

　　3. Avoid smoking, drinking, and spicy, numbing, and pungent foods, such as scallions, garlic, ginger, Sichuan peppercorns, chili, and so on.

　　4. Avoid moldy, fried, smoked, and preserved foods, such as salted fish, preserved vegetables, walnuts, peanuts, sunflower seeds, sesame, fried foods, oil-puffed pastries, butter, ice cream, and so on.

　　5. Avoid hard, sticky, indigestible foods, such as leeks, celery, and other rough fiber foods that stimulate the intestines, such as coarse grains, corn, glutinous rice, and so on.

　　The main treatment method for elderly pancreatic cancer is to take surgical resection, and adjuvant radiotherapy and chemotherapy to prevent tumor recurrence. However, the specific treatment plan still needs to be formulated after systematic examination, diagnosis and staging.

　　First, treatment

　　1. Routine treatment

　　For patients with localized lesions who can be operated on, it is advisable to try to perform an exploratory laparotomy, perform radical surgery, and necessary preoperative and postoperative chemotherapy, postoperative adjuvant chemotherapy and (or) radiotherapy. For patients who cannot be resected after exploration, palliative surgery (such as biliary decompression and drainage or gastrojejunostomy) can be performed to alleviate symptoms such as jaundice obstruction, and comprehensive treatment including postoperative radiotherapy and chemotherapy. For patients with localized lesions but unable to perform exploratory surgery, radiotherapy and chemotherapy combined with other drugs can be used. For patients with widespread lesions, chemotherapy, traditional Chinese medicine, and biological response modifiers are the main treatments, and local radiotherapy is performed if necessary. In the advanced stage, for patients with poor general condition, chemotherapy is not suitable, and supportive treatment, symptomatic treatment, and other drug treatments should be performed. For pain, analgesic treatment should be given. Adjuvant chemotherapy after radical surgery can start around 3 weeks after surgery, without surgical complications, generally every 3 months for 1 course, a total of 3 courses.

　　(1) Surgical treatment: Early surgical resection is the most effective measure for the treatment of pancreatic cancer, but most patients with clinical symptoms and confirmed diagnosis after examination belong to advanced pancreatic cancer, with a resection rate of only 10% to 20%. The following surgical methods are available:

　　① Pancreaticoduodenectomy.

　　② Pancreas-preserving pylorus-preserving pancreaticoduodenectomy.

　　③ Extended radical surgery.

　　④ Pancreatic body and tail resection.

　　⑤ Paliative surgery.

　　(2) Radiotherapy: With the continuous improvement of radiotherapy technology, the efficacy of pancreatic cancer radiotherapy has been significantly improved, which can often significantly improve symptoms and extend survival time. Intraoperative and postoperative radiotherapy can be performed, supplemented by chemotherapy. For patients without surgical conditions, high-dose local irradiation and local implantation of radioactive nuclides can be performed.

　　(3) Chemotherapy: Although early diagnosis of pancreatic cancer is difficult, the resection rate is low, and it is not sensitive to radiotherapy and chemotherapy, timely use of comprehensive treatment including surgery, radiotherapy, chemotherapy, biological response modifiers, hormones, and so on, including preoperative, intraoperative, and postoperative radiotherapy or chemotherapy. The effects of radiotherapy and (or) chemotherapy and other drug treatments for inoperable locally advanced patients are better than those of single treatment methods, and there is a possibility of extending survival time.

　　Some chemotherapy drugs increase the sensitivity to radiation, among which SF11 and its derivatives F1207, UFT (Optifast Tablets), and others are commonly used. Therefore, for inoperable locally advanced pancreatic cancer and cases that have been resected, the use of SFU combined with radiotherapy can achieve certain effects.

　　(4) Electrochemical Therapy: Pancreatic cancer patients with confirmed inoperable lesions and no distant metastasis can undergo electrochemical therapy. The principle of electrochemical therapy is to directly apply direct current to the lesion site, changing the local chemical environment to kill tumor cells. By exposing the lesion through laparotomy and performing electrochemical therapy under direct vision, a relatively ideal therapeutic effect is achieved, with a pain relief rate of 88.9%, effective pain relief time of 3 to 28 months, averaging 6 months; local control rate (CR+PR) of the lesion site is 65.63%, median survival time is 11.6 months. The main complications are pancreatic fistula, which heals within one month after peritoneal drainage. In the future, we routinely cover the treatment site with omentum during surgery and use cimetidine (methylcyclohexylguanidine) prophylactically after surgery, and this complication has not occurred again.

　　(5) Immunotherapy: Common antitumor immunological preparations include: ① Levamisole; ② Thymus extract; ③ Interferon inducers, such as polyinosinic-polycytidylic acid; ④ Transfer factor (TF); ⑤ Immunoribonucleic acid (IRNA).

　　(6) Endocrine Therapy: Some scholars believe that estrogen receptor (ER), progesterone receptor (PR), PAN, and Con-A expression are related to pancreatic cancer tissues, especially ER levels. Estriol treatment may have a certain effect according to the situation.

　　2. Optimal Regimen

　　The preferred chemotherapy regimen for surgery and chemotherapy is FAM and GP regimens.

　　3. Rehabilitation Treatment

　　Rehabilitation treatment for pancreatic cancer includes the following aspects:

　　(1) Psychological Support for Patients: In the process of rehabilitation treatment, the education of patients and their families is the most important. Good psychological preparation and active cooperation with treatment are beneficial to recovery.

　　(2) Nutritional Support: Pancreatic cancer patients have poor appetite, and should be provided with sufficient water, calories, protein, and other nutrients to ensure their physical strength.

　　II. Prognosis

　　Surgical treatment is the only method to cure pancreatic cancer, but less than 20% of patients are eligible for surgery. Their median survival time after surgery is 18 to 20 months, and the 5-year survival rate is 15%. Many factors affect the prognosis of pancreatic cancer after surgery, such as tumor diameter ≤2.5cm, well-differentiated adenocarcinoma without lymph node metastasis has a better prognosis than poorly differentiated cancer with larger tumor size. The prognosis is relatively better for patients with no residual tumor tissue at the surgical resection margin.