Pancreatic cancer is a common pancreatic tumor, a malignant tumor of the gastrointestinal tract that is highly malignant and difficult to diagnose and treat. 90% of these tumors are ductal adenocarcinomas originating from the epithelium of the ducts, and their morbidity and mortality rates have increased significantly in recent years. The early diagnosis rate of pancreatic cancer is low, and the surgical resection rate is also low. The incidence of this disease is higher in men than in women, and the ratio of men to women is about 1.5 to 2:1. Men are much more common than premenopausal women, and the incidence of postmenopausal women is similar to that of men.
The etiology of pancreatic cancer is not well understood, and it is related to smoking, alcohol consumption, high-fat and high-protein diet, excessive coffee consumption, environmental pollution and genetics; recent survey reports found that the incidence of pancreatic cancer in the diabetic population is significantly higher than that in the general population; it has also been noted that the proportion of pancreatic cancer in patients with chronic pancreatitis is significantly higher; there are also many factors related to the occurrence of this disease, such as Occupation, environment, geography, etc.
Clinical manifestations
The clinical manifestation of pancreatic cancer depends on the location of the tumor, the early or late stage of the disease, the presence or absence of metastasis and the involvement of adjacent organs. The clinical features are short duration, rapid progression and rapid deterioration. The most common symptoms are upper abdominal fullness and discomfort, pain and jaundice. Although there is conscious pain, not all patients have pressure pain, and if there is pressure pain it is consistent with the site of conscious pain.
1.Abdominal pain
Pain is the main symptom of pancreatic cancer. Pain may exist regardless of whether the cancer is located in the head or tail of the body of the pancreas. Pain in the middle abdomen, left upper abdomen or right upper abdomen is common, while a few cases complain of pain in the left and right lower abdomen, around the umbilicus or the whole abdomen, or even testicular pain, which is easily confused with other diseases. When cancer involves visceral peritoneum, peritoneum or retroperitoneal tissues, there may be pressure pain in the corresponding area.
2.Jaundice
Jaundice is an important symptom and sign of pancreatic cancer, especially pancreatic head cancer. Jaundice is obstructive in nature, accompanied by deep yellow urine like soy sauce, yellow skin and progressive aggravation with skin itching, as well as clay-like stool, which is caused by the invasion of the lower part of the common bile duct or compression by the tumor. The jaundice is progressively aggravated and is unlikely to subside completely, although there can be slight fluctuations. The temporary reduction of jaundice is related to the remission of inflammation around the jugular abdomen in the early stage, while in the late stage, the jaundice produced by the jugular abdomen tumor is more likely to fluctuate due to the ulceration and decay of the tumor invading the lower end of the common bile duct.
Once jaundice appears in pancreatic body tail cancer, it is mostly in the advanced stage and occurs due to the tumor spreading to the head of the pancreas. A small number of patients with pancreatic cancer develop jaundice in late stages due to liver metastases. About 1/4 of the patients have persistent pruritus, which is often progressive.
3. Gastrointestinal symptoms
The most common symptoms are loss of appetite, followed by nausea, vomiting, diarrhea, constipation or even black stool, and often steatorrhea. The loss of appetite is related to the lower end of the common bile duct and the pancreatic duct being blocked by the tumor, and the bile and pancreatic juice cannot enter the duodenum. Obstructive chronic pancreatitis of the pancreas leads to poor exocrine function of the pancreas, which also inevitably affects appetite. A small number of patients present with obstructive vomiting. About 10% of patients have severe constipation.
Diarrhea due to pancreatic exocrine malfunction, steatorrhea is a more advanced presentation and is relatively rare. Upper gastrointestinal bleeding can also occur in pancreatic cancer, manifested as vomiting blood and black stools. Splenic vein or portal vein is embolized due to tumor invasion, secondary to pancreatic-derived portal hypertension, and occasionally ruptured hemorrhage of lower esophageal varices may occur.
4.Loss of weight and weakness
Unlike other cancers, pancreatic cancer is often associated with wasting and weakness at the initial stage.
5.Abdominal mass
The abdominal mass is the result of the development of the cancer itself and is located where the lesion is. If the mass is felt, it is mostly in the progressive or advanced stage. Chronic pancreatitis masses can also be felt in the abdominal masses, which are not easily distinguished from pancreatic cancer.
6. Symptomatic diabetes mellitus
The initial manifestation of diabetes mellitus in a few patients, that is, diabetes mellitus before the main symptoms of pancreatic cancer, such as abdominal pain and jaundice, and the accompanying wasting and weight loss are mistaken for the manifestation of diabetes mellitus without considering pancreatic cancer. This means that pancreatic cancer may have occurred on top of the original diabetes mellitus.
7. Thrombophlebitis
Patients with advanced pancreatic cancer may develop thrombophlebitis or arterial thrombosis.
8. Psychiatric symptoms
Some patients with pancreatic cancer may show anxiety, impatience, depression, personality changes and other psychiatric symptoms.
9. Fluid accumulation in the abdominal cavity
It usually appears in the late stage of pancreatic cancer, mostly due to peritoneal infiltration and spread of tumor. The fluid may be bloody or plasma, and the hypoproteinemia of advanced cachexia may also cause fluid in the abdominal cavity.
10.Other
In addition, patients often complain of fever and marked weakness. There may be high fever or even chills and other symptoms similar to cholangitis, so it is easy to be confused with cholelithiasis and cholangitis. Of course, when there is biliary obstruction combined with infection, there may also be chills and high fever. Some patients may also have small joint redness, swelling, pain, heat, subcutaneous fat necrosis around the joint and unexplained testicular pain. The supraclavicular, axillary or inguinal lymph nodes may also be enlarged and hardened due to metastasis of pancreatic cancer.
Auxiliary examination
Intractable epigastric pain, pain radiating to the lower back, obvious at night, aggravated when lying on the back, and relieved by sitting in a curled or forward position are highly suggestive of pancreatic cancer, and further laboratory and other ancillary examinations are needed.
Ultrasound, CT, MRI, ERCP, PTCD, angiography, laparoscopy, tumor marker determination, oncogene analysis, etc. are quite helpful in determining the diagnosis of pancreatic cancer and whether it can be surgically removed. However, surgeons still cannot neglect the medical history questioning and comprehensive physical examination of the patient.
To assess the safety of radical surgery, the information obtained from detailed history and careful physical examination is more important than a single cardiac or pulmonary function test. Ultrasound, CA19-9, and CEA can be used as screening tests in general, and once pancreatic cancer is suspected, enhanced thin-section CT of the abdomen is necessary. If the patient has jaundice and it is severe, ERCP and PTCD can be chosen when the diagnosis cannot be confirmed after CT examination. If the tube placement and drainage is successful, the surgery can be delayed for 1 to 2 weeks for patients with severe jaundice.
MRI is not superior to CT in the diagnosis of pancreatic cancer, and it is clinically relevant to choose angiography and/or laparoscopy to avoid unnecessary surgical exploration when pancreatic cancer has been diagnosed but cannot be surgically resected. In addition, PET-CT is currently meaningful for systemic tumor evaluation of pancreatic cancer, but its cost is expensive.
For patients with pancreatic cancer or periampullary cancer that cannot be surgically resected and have no indication for palliative surgery, fine needle aspiration is necessary to obtain cytology when chemotherapy and radiotherapy are proposed. This test is usually not performed in patients with the possibility of surgical resection. This is because fine needle aspiration may lead to the spread of cancer cells in the abdominal cavity.
Diagnosis
Based on the morbidity characteristics of pancreatic cancer patients, it is currently believed that patients over 40 years old, with unprovoked abdominal pain, fullness and discomfort, loss of appetite, wasting, weakness, diarrhea, back pain, recurrent pancreatitis or sudden onset of diabetes without family history should be considered as a high-risk group for pancreatic cancer and should be alerted to the possibility of pancreatic cancer at the time of consultation.
Differential diagnosis
Pancreatic cancer should be differentiated from stomach diseases, jaundiced hepatitis, cholelithiasis, cholecystitis, primary liver cancer, acute pancreatitis, chronic pancreatitis, pot-belly cancer, gallbladder cancer, etc.
Treatment
At present, the principle of treatment is still based on surgery, combined with radiotherapy and other comprehensive treatment.
1.Surgical treatment of pancreatic cancer
Surgery is the only possible way to cure pancreatic cancer. Surgical methods include pancreaticoduodenectomy, expanded pancreaticoduodenectomy, pylorus-preserving pancreaticoduodenectomy, total pancreatectomy, and pancreatic tail resection combined with splenectomy. However, due to the difficulty of early diagnosis of pancreatic cancer, the surgical resection rate is low, and the five-year survival rate after surgery is still low.
2.Palliative treatment of pancreatic cancer
For cases of pancreatic cancer that cannot be resected radically, it is often necessary to relieve the obstructive jaundice, and if possible, internal drainage of the gallbladder or bile duct jejunostomy or even internal drainage of the gallbladder or bile duct jejunostomy T-tube bridge can be performed. The stent can be placed under endoscope to relieve the obstruction, but the general survival time is not more than six months.
3.Comprehensive treatment of pancreatic cancer
Due to its high malignancy, pancreatic cancer has a low surgical resection rate and poor prognosis. Although surgery is still the primary treatment method, a large proportion of patients are still found late and lose the chance of radical treatment, so comprehensive treatment of pancreatic cancer is needed. To date, as with most tumors, there is no single highly effective and fully applicable combination treatment option. The current comprehensive treatment is still based on surgical treatment, supplemented by radiotherapy and chemotherapy, and is exploring new methods of combining biological therapies such as immunotherapy and molecular therapy.
(1) Radiation therapy Pancreatic cancer is a tumor with relatively low sensitivity to radiotherapy.
(2) Chemotherapy Chemotherapy should be routinely administered to pancreatic cancer that cannot be removed surgically or to prevent recurrence after surgery. Gemcitabine is still the drug of choice in chemotherapy for pancreatic cancer, and can be used in combination with other chemotherapeutic drugs. The route of chemotherapy is intravenous treatment and arterial cannulation intervention.
(3) Biological therapy Biological therapy includes immunotherapy and molecular therapy. With the rapid development of immune and molecular biology research, this will be the most challenging research because some completely new methods must be developed to treat refractory tumors like pancreatic cancer: (1) Gene therapy: Gene therapy is emerging, but most of them are still in pre-clinical stage, and few of them are in clinical stage I or II trials. (2) Immunotherapy: applying immune agents to enhance the immune function of the body is part of the comprehensive treatment.
(4) Other therapies Warmth therapy is based on the higher sensitivity of tumor cells to heat in an acidic environment and the acidic tendency within the tumor due to anaerobic metabolism. Pancreatic cancer is a hypoxic tumor with low sensitivity to radiotherapy, but with increased sensitivity to heat. In recent years, technical improvements have led to the application of warm therapy. The commonly used temperature is 44°C. However, the heating and temperature measurement methods need to be improved.
4.Symptomatic support therapy
In advanced stage of adenocarcinoma, those with steatorrhea due to pancreatic exocrine insufficiency can take pancreatic enzyme preparation at meal to help digestion. For intractable abdominal pain, analgesics, including opioid analgesics, should be given; if necessary, 50%-75% ethanol should be used for abdominal plexus injection or sympathectomy. Radiotherapy or interventional therapy may provide pain relief in some patients. Nutritional support should also be enhanced to improve nutritional status.
Healing
Pancreatic cancer is a highly malignant tumor with a very poor prognosis. Patients with untreated pancreatic cancer have a survival period of about 4 months, patients treated with bypass surgery have a survival period of about 7 months, and patients with radical resection usually survive for 16 months. Early diagnosis and early treatment are the only keys to improve and enhance the prognosis of pancreatic cancer, and the application of adjuvant therapy such as radiotherapy after surgery can improve the survival rate. For patients with adjuvant chemotherapy and radiotherapy after surgery, their 2-year survival rate can reach 40%.