I. Overview
Cancer of the pancreas is a common pancreatic tumor with a high degree of malignancy, and in recent years, its incidence has been on the rise both at home and abroad. More than half of pancreatic cancers are located in the head of pancreas, and about 90% are ductal adenocarcinomas originating from the epithelium of the ducts.
In order to further standardize the diagnosis and treatment of pancreatic cancer in China, improve the level of pancreatic cancer treatment in medical institutions, improve the prognosis of pancreatic cancer patients, and protect medical quality and medical safety, this specification is formulated.
Diagnostic techniques and applications
(A) High risk factors. Old age, history of smoking, high-fat diet and overweight body mass index are risk factors for pancreatic cancer, and exposure to chemicals such as β-naphthylamine and benzidine can lead to increased incidence.
(ii) Clinical manifestations.
Most patients with pancreatic cancer lack specific symptoms and initially present only with upper abdominal discomfort and vague pain, which can be easily confused with other digestive system diseases. When patients develop low back pain, the tumor invades the retroperitoneal plexus, which is an advanced manifestation.
Patients with pancreatic cancer have wasting and weight loss in the early stage of the disease.
Symptoms such as indigestion, vomiting and diarrhea are often present.
The possibility of pancreatic cancer needs to be highly suspected in patients over the age of 18 who have any of the following manifestations, and even more so if the patient is a smoker.
(1) Obstructive jaundice of unknown origin.
(2) Recent unexplained weight loss >10%.
(3) Recent unexplained epigastric or low back pain.
(4) Recent vague and unexplained dyspepsia with normal endoscopy.
(5) Sudden onset of diabetes without predisposing factors, such as family history, obesity.
(6) Sudden onset of unexplained steatorrhea.
(7) Episodes of spontaneous pancreatitis.
(C) Physical examination.
Patients with pancreatic cancer lack specific physical signs at the early stage of the lesion, and most of them are in the progressive or advanced stage when the signs appear.
Jaundice. Jaundice is a common physical sign in patients with pancreatic head cancer, which is manifested as yellowing of skin and mucous membrane all over the body, whitening of stool, yellowing of urine and itching of skin.
Abdominal mass. Patients with pancreatic cancer with palpable abdominal masses are mostly in advanced stages and rarely can be removed by radical surgery.
(iv) Imaging examination.
Ultrasonography: It is the preferred method for pancreatic cancer diagnosis. It is easy to operate, non-invasive, non-radioactive, and can be observed in multiple axes, and can better show the internal structure of the pancreas, whether there is obstruction in the bile duct, the site of obstruction, and the cause of obstruction. The limitation is that the field of view is small, and it is sometimes difficult to observe the pancreas, especially the tail of the pancreas, due to the influence of gas and body size in the stomach and intestinal tract.
Examination: It is the best non-invasive imaging method to examine the pancreas and is mainly used for the diagnosis and staging of pancreatic cancer. Plain scan can show the size and location of the lesion, but it cannot accurately diagnose the pancreatic lesion qualitatively and shows the poor relationship between the tumor and the surrounding structures. Enhancement scan can better show the size, location, morphology, internal structure and relationship with surrounding structures of the pancreatic mass. It can accurately determine the presence or absence of liver metastases and show enlarged lymph nodes.
MRCP and magnetic resonance pancreaticobiliary imaging (MRCP): not as the preferred method for diagnosis of pancreatic cancer, but when patients are allergic to CT-enhanced contrast agent, MR can be used instead of CT scan for diagnosis and clinical staging; in addition, MRCP has obvious advantages on the presence or absence of biliary obstruction, the site of obstruction and the cause of obstruction, and it is safe compared with ERCP and PTC, and for pancreatic head cancer, MR can be used as useful supplement to CT scan.
Upper gastrointestinal tract imaging: It can only show indirect signs caused by compression and invasion of the gastrointestinal tract by some advanced pancreatic cancer and is not specific. It has been replaced by cross-sectional imaging.
(E) Blood immunobiochemical examination.
Blood biochemical examination: early stage has no specific blood biochemical changes, but tumor obstruction of bile duct can cause elevated blood bilirubin, accompanied by enzymatic changes such as glutamic aminotransferase and glutamic oxalacetic aminotransferase. Forty percent of patients with pancreatic cancer have elevated blood glucose and abnormal glucose tolerance.
Blood tumor markers: CEA and CA19-9 are elevated in the serum of pancreatic cancer.
(vi) Histopathological and cytological diagnosis. Histopathological or cytological examination can determine the diagnosis of pancreatic cancer. It can be obtained by preoperative/intraoperative cytological aspiration, biopsy, or referral to a higher level hospital with appropriate conditions for endoscopic ultrasound aspiration/biopsy.
(vii) Differential diagnosis of pancreatic cancer.
Chronic pancreatitis: Chronic pancreatitis is a recurrent progressive and extensive pancreatic fibrotic lesion that leads to pancreatic duct stenosis and obstruction, obstruction of pancreatic fluid drainage and dilation of the pancreatic duct. The main manifestations are abdominal pain, nausea, vomiting and fever. The clinical manifestations of pancreatic cancer and epigastric discomfort, indigestion, diarrhea, loss of appetite and weight loss can be distinguished as follows.
(1) Chronic pancreatitis has a slow onset, long history, often recurrent, acute attacks can appear elevated blood and urine amylase, and rarely jaundice symptoms.
(2) CT examination of the chest shows irregular contours of the pancreas, nodular elevation and uneven density of the pancreatic parenchyma.
(3) Plain film and CT examination of the abdomen of patients with chronic pancreatitis can help diagnose calcified spots in the pancreatic area.
Jugular carcinoma: Jugular carcinoma occurs at the confluence of common bile duct and pancreatic duct. Jaundice is the most common symptom, and jaundice can appear at the early stage of tumor development. Differentiation is as follows.
(1) Intermittent jaundice may appear due to necrosis and detachment of tumor.
(2) Duodenal hypotension angiography can show filling defect and mucosal destruction in the papilla of duodenum “bilateral sign”.
(3) Ultrasound, CT, MRI, ERCP and other examinations can show dilated pancreatic duct and bile duct, low bile duct obstruction, “double duct sign”, and occupying lesions in the jugular abdomen.
Cystic adenoma and cystic adenocarcinoma of the pancreas: cystic tumors of the pancreas are rare clinically and occur mostly in female patients. Clinical symptoms, imaging tests, treatment and prognosis are different from those of pancreatic cancer. Ultrasound and CT can show cystic lesions in the pancreas with regular cystic cavity, while cystic lesions and irregular cystic cavity only appear in pancreatic cancer with central necrosis.
Other: some rare pancreatic lesions are more difficult to be diagnosed clinically.
Classification and staging of pancreatic cancer
(A) Histological types of pancreatic cancer. Refer to the 2006 edition of WHO histological classification of pancreatic cancer (Annex 1).
(B) Staging of pancreatic cancer.
The definitions of T, N and M in TNM staging of pancreatic cancer.
1. Primary tumor (T).
Primary tumor cannot be detected.
No evidence of primary tumor.
Carcinoma in situ M1 Distant metastasis.
Tumor is confined to the pancreas with a maximum diameter ≤ 2 cm*.
Tumor confined to the pancreas with a maximum diameter of ≥2 cm*.
Tumor extends outside the pancreas but does not involve the celiac artery and superior mesenteric artery.
The tumor invaded the celiac artery and superior mesenteric artery.
2.Regional lymph nodes (N).
Regional lymph nodes cannot be detected.
No regional lymph node metastasis.
Regional lymph node metastasis.
3.Distant metastasis (M).
No distant metastasis can be detected.
No distant metastasis.
Distant metastasis.
Note: * Measured by CT (maximum diameter) or resected specimen analyzed by pathology.
TNM staging of pancreatic cancer
TNM staging of pancreatic cancer (UICC/AJCC 2002)
Staging
Ⅰ
Ⅰ
Ⅱ
II
Ⅲ Ⅳ
, N0.
, M0.
, N0.
, N0, , N0, , N0
, N1.
Any N.
any T ,any