Pancreatic cancer: diagnosis

From laboratory data for pancreatic cancer, as a rule, there is an acceleration of ESR, iron deficiency anemia, which is especially pronounced during the decay of the tumor and the occurrence of bleeding, is often detected. Even in the absence of obvious signs of anemization, in many cases, when coprological examination, signs of latent bleeding are found. Laboratory signs of hypercoagulable blood are determined relatively often.

In tumors that affect a significant part of the pancreatic parenchyma, or when the main duct is compressed, symptoms of its exocrine insufficiency appear, "pancreatogenic" diarrhea, steatorrhea, and creatorrhea. With the compression or germination of the terminal part of the common bile duct or BSD, cholestasis, hyperbilirubinemia (due to direct and partial unbound bilirubin), hypercholesterolemia occur; the stool becomes discolored. Often, the content of amylase, trypsin and lipase in the blood serum, as well as amylase in the urine (in a single or 24-hour portion thereof) is increased, especially when the tumor is compressed by the ducts of the gland. Of some importance is the study of the activity of enzymes in duodenal contents before and after stimulation of the gland with secretin and pancreosimine, as well as a synthetic preparation similar to pancreosimine, cerulein; in many cases, a decrease in the secretion of pancreatic juice is determined, and the activity of the enzymes in it is reduced to a lesser extent. However, this research is quite difficult to conduct and so far it is used only in a few medical institutions. In addition, these data, indicating excretory pancreatic insufficiency, are only indirect signs of its damage and can occur in other pancreatic diseases. The increase in serum amylase activity and hyperamilazuria is also not pathognomonic for pancreatic cancer. Moreover, in a moderate degree of severity, they can be determined with many diseases of the abdominal cavity.

Some diagnostic value has a cytological study of duodenal contents, but tumor cells in it are not found in all cases of this disease.

Violations of carbohydrate metabolism (hyperglycemia or glycosuria) indicate a lesion of the endocrine gland function (primary or secondary). These symptoms are noted in adenocarcinoma in 30-50% of cases. They become more important if they occur shortly before other manifestations of the underlying disease.

In the absence of jaundice and metastases in the liver, functional tests of the liver may remain normal. Attention should be paid to the activity of ribonuclease and alkaline phosphatase. The latter can be increased several months before the appearance of other signs of a tumor. An increase in the activity of other enzymes, an increase in the level of a2-globulin, an increase in ESR, anemia and leukocytosis are more frequent in the III-IV stage and are not specific for pancreatic cancer.

Recently, much attention has been paid to tumor markers in the recognition of its cancerous lesions.

Among the instrumental methods for diagnosing pancreatic cancer, traditional X-ray examination is the most accessible and includes a number of valuable techniques. In the case of polycystonic X-ray examination of the stomach and duodenum, displacement, deformation and deformation of these organs, expansion of the duodenal loop; infiltration and ulceration of the wall. However, this method can detect only advanced stages of pancreatic cancer (mainly its head).

X-ray diagnostic methods are continuously improved. More than 30 years ago, duodenography under conditions of artificial hypotension (filling through the duodenal probe of the duodenum after preliminary intravenous administration of 2 ml of a 0.1% solution of atropine sulfate) was used to detect pancreatic head cancer (as well as some other diseases). In this case, it is possible to follow very clearly the course of the walls of the duodenum, atonic and stretched contrast medium, and to determine the slightest impressions on the inner wall caused by the enlargement of the pancreas head, as well as the two-contouring of the medial wall. When the tumor of the wall of the duodenum is often detected, the symptom of Frostberg. In advanced cases, sometimes expressed stenosis of the duodenum is determined. If a body or tail cancer is suspected, splenoportography is made, selective angiography, which are more complicated techniques and sometimes cause complications. If suspicion of narrowing the terminal section of the common bile duct due to compression or germination of the head of the pancreas, intravenous choleography was widely used at one time. However, these conventional methods of contrasting bile ducts are ineffective in obstructive jaundice; therefore, to determine the level of obstruction, percutaneous hepatocholangiography is used. With cancer of the head of the pancreas, a characteristic break in the image is revealed - the "stump" of the common bile duct on the intra-pancreatic or retro-duodenal level; However, this method can also cause complications. Therefore, it can be used only on very strict indications.

Selective angiography of the celiac trunk and splenic artery allows to determine the localization, the extent of the spread of the process and makes it possible to judge its operability. The accuracy of this complex method in the hands of an experienced researcher reaches 89-90%. Signs of cancer in angiography are the detection of avascular zones, infiltration of blood vessels (symptom "usurizatsii", symptom "stump", etc.). The above signs can be detected mainly when the diameter of the tumor reaches 5 cm or more. Differential diagnostics of pancreatic cancer and pseudotumoral form of chronic pancreatitis is difficult, the hagiographic signs of which coincide in 10% of cases. Carrying out angiography in almost 7% is accompanied by complications.

However, every year the possibility of direct examination of the main duct and pancreatic tissue increases, instrumental methods of investigation are improved and significantly improve the accuracy of diagnosis. In the last 20-15 years, the methods of ultrasound and CT developed and widely used have practically superseded complex and not entirely safe methods, significantly increasing the accuracy of pancreatic cancer diagnosis. With the help of these methods, focal pancreas with a diameter of 1.5-2 cm and more are detected with almost 100% accuracy (erroneous conclusions are rare and account for only a few percent of cases). Even more accurate is the MRI method, which makes it possible to identify focal formations in an organ with a diameter of just a few millimeters. However, the equipment for this study is very expensive and is available only in the largest hospitals and diagnostic centers.

The method of scanning the pancreas with radioactive ⁷⁵ 8e-methionine, relatively well accumulating in the pancreas, but at present they are rarely used. Focal defects in the pancreas, with its cancerous lesions and other changes in it, are fairly well detected with the help of echography. A great advantage of ultrasound, in addition to high diagnostic accuracy, is the possibility, without any harm to the patient, of repeated, and sometimes, if necessary, evaluation of the pathological process in dynamics - and repeated use. With the help of ultrasound, it is possible to identify tumor metastases in the liver and some other organs. Ultrasound is used for both indicative and final diagnosis of pancreatic cancer. Under the control of ultrasound or CT scan, puncture pancreas biopsy is performed in necessary cases, and liver liver metastases are suspected. With the help of gastroduodenoscopy in pancreatic head cancer, there are some indirect signs that allow one to suspect this disease: deformity, depression and disruption of the peristalsis of the posterior wall of the stomach and duodenum, enveloping the head of the pancreas. Especially for the diagnosis of this disease, this method is almost never used because of inaccurate results. However, with an approximate diagnostic examination of the patient, with uncertainty of the diagnosis, but the presence of indeterminate dyspeptic complaints, pain in the upper abdomen, in some cases this method allows to suspect a tumor lesion of the head of the pancreas and gives the doctor an opportunity to schedule a special targeted research. In some cases, the ERPHG method is used in which, using modern flexible duodenofibroscopes, a contrast agent is introduced into the main duct and its branches through a special catheter, and then the "broken" (non-filling) of some ducts and the tumor infiltration sites can also be detected on the X-rays taken afterwards. ERCPH is one of the relatively accurate methods for diagnosing pancreatic cancer; with his help to establish the correct diagnosis is possible in almost 90% of cases. When conducting ERPHG you can take the material for a cytological study. When catheterization of BSD and the introduction of contrast medium, it is possible to detect destruction of the main passages of the main pancreatic duct, to determine the place of obstruction with jaundice. There are four main types of changes in the ducts in a tumor:

1. break;
2. stenosis;
3. "Stripped duct";
4. destruction of lateral ducts with unchanged major.

Approximately 3% of cases, according to different authors, the study may be accompanied by complications (even in the form of acute pancreatitis).

The pancreas with laparoscopy is usually not available for visualization, and the diagnosis is made on the basis of indirect symptoms.

In the most difficult situations for diagnosis, one has to resort to diagnostic laparotomy. But even in these cases, there are great difficulties: in 9% of the patients we observed with laparotomy, the cancer of the gland was not recognized; Similar difficulties can also occur in the prozector before careful dissection and analysis of the tumor mass.

An important prerequisite for the successful diagnosis of cancer in the future is the introduction of a serological method, that is, the definition of oncofetal pancreatic antigen, a-fetoprotein. The standard methods of its determination are already beginning to be used in large diagnostic oncological and gastroenterological institutions.

A very large number of diagnostic methods that have appeared in recent years, facilitating the detection of pancreatic cancer, sometimes puts the doctor in a quandary. Questions arise: how to optimally make a plan for diagnostic search, what instrumental and diagnostic methods for suspicion of pancreatic tumor damage apply first of all, and which, if there is a continuing ambiguity in the diagnosis, in the subsequent, i.e., how to determine the sequence of laboratory-instrumental examination of the patient, in the shortest possible time to establish an accurate diagnosis and at the same time to provide the greatest possible safety for the patient (given that many invasive and radiation methods m Gut cause in some cases, certain complications, no matter how experienced the doctor was performing these studies).

Thus, first of all it is necessary to use non-invasive diagnostic methods. In this regard, attention is deserved, first, ultrasound, then X-ray examination, CT, determination of exocrine gland function. Angiography and ERPHG, laparoscopy and other invasive and rather difficult to perform and unsafe for the patient methods of research usually produce if possible or necessary surgery and no serious contraindications for their use. This principle is followed by all experienced doctors, although some changes in the sequence of application of diagnostic methods may be due to the clinical features of the manifestation and course of the disease, as well as local opportunities for using certain diagnostic methods.

Differential diagnosis. Pancreatic cancer, as indicated, can occur with an extremely diverse clinical picture, imitating various other diseases (stomach cancer, cholelithiasis, perforated ulcer of the stomach and duodenum, lumbosacral radiculitis, viral hepatitis - icteric forms, subdiaphragmatic abscess, etc.). . Therefore, the diagnosis and differential diagnosis of this disease is often extremely difficult.

Most often it is necessary to carry out differential diagnostics with subhepatic jaundice between the tumor of the head of the pancreas, which compresses and sprouts the common bile duct, and the gallstone that caused its obturation. In this case, it should always be borne in mind that in cholelithiasis, obstruction with a common biliary duct and jaundice occurs after a severe biliary colic attack, which is not characteristic of pancreatic cancer. Ultrasound and CT in cancer can identify a focus (or several foci) of compaction in the pancreas. The classic differential-diagnostic feature is the Courvoisier symptom: it is usually positive for pancreatic cancer and is negative when the stone is clogged with the common bile duct (since the gallbladder is usually cicatrally wrinkled due to a previous long calculous cholecystitis). This symptom on the basis of palpation is revealed in 27.8% of patients with pancreatic head cancer. Modern diagnostic methods - ultrasound, CT, can reveal or confirm the increase in the gallbladder in all cases of its actual increase (it should be borne in mind that if a patient, long before the onset of his pancreatic cancer, suffered from cholelithiasis with frequent exacerbations of biliary colic and cholecystitis, the gallbladder can be wrinkled from it due to the inflammation-scar process, and when the bladder duct is obstructed with a stone it is turned off). These same studies can determine the presence of concrements in the gallbladder, tumor metastases to the liver and other pathological changes.

Cancer of the BSD proceeds in most cases with the same basic symptoms as the head of the pancreas, but with it often there is an intestinal bleeding. The diagnosis is confirmed by duodenofibroscopy with targeted tumor biopsy. Obstructive jaundice can also be caused by a tumor lesion of the hepatic ducts, the common bile duct (which is relatively rare, but you can not forget about it), a growing tumor of the gallbladder. Jaundice can be a consequence of the adhesion process with narrowing of the bile ducts (after cholecystectomy, resection of the stomach, etc.), compression of the ducts with enlarged lymph nodes in the gates of the liver, etc. Therefore, with the help of modern, highly highly informative methods, it is always necessary to specify the localization and the cause of the disorder outflow of bile.

Chronic inflammation of the pancreas can also cause stenosis and compression of the ducts. For differential diagnosis of the tumor, it must be borne in mind that in the case of chronic pancreatitis, the changes in the ducts of the gland are more common; there are cystic enlargements of them; The narrowing of the distal section of the common bile duct usually starts from the BSD itself.

Focal lesions of the pancreas can be caused by metastases of malignant tumors of other organs (occur relatively rarely, more often from the stomach), benign tumor, cyst or several pancreatic cysts, syphilitic gum and some other diseases, which should also be taken into account in differential diagnosis. A thorough examination of the patient using the above modern methods facilitates correct diagnosis.

Differential diagnosis of icteric form of pancreatic cancer is based on the classic features of differences in hepatic and subhepatic jaundice; in necessary cases, an ultrasound of the pancreas, CT; necessarily, if there are doubts, determine the serum hepatitis antigens and antibodies to them.

[1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12]