Last updated date: 30-Mar-2023
Originally Written in English
The pancreas is a spongy, tube-shaped organ with a length of around 15 cm that is situated in the upper abdomen between the stomach and spine. A normal, healthy pancreas is made up of stellate cells, which are largely inactive, endocrine islets, centro-acinar cells, which are the transitional area between acinar and ductal cells, and acinar cells, which secrete the digestive enzymes, and ductal cells, which secrete bicarbonate. When the pancreas experiences strange DNA mutations, the pancreatic cells expand and divide out of control, resulting in tumors. One of the most deadly and aggressive cancers, pancreatic cancer is known to be fatal. Pancreatic cancer sometimes manifests at an advanced stage and has frequently spread to other body areas by the time it is diagnosed.
Clinically referred to as an adenocarcinoma, pancreatic ductal adenocarcinoma (PDAC) represents more than 90% of pancreatic malignancies. It is a malignant tumor that develops in the epithelial cells of glandular structures in the pancreatic ductal cells. PDAC is the 10th most frequent cancer, however, due to the dismal survival rates, it is the seventh greatest cause of cancer death globally. Adenosquamous carcinoma, squamous cell carcinoma, giant cell carcinoma, acinar cell carcinoma, and small cell carcinoma are some less frequent exocrine pancreatic malignancies. The prognosis for pancreatic cancer has stayed unaltered throughout the last 20 years, and it is still a fatal disease today. Clear epidemiological understanding, appropriate prevention, and scientific regulation of early detection are all necessary for improving patient outcomes. Consequently, it is essential to comprehend the epidemiological characteristics, growth patterns, and risk factors of pancreatic cancer in detail to design logical preventative strategies for clinical value.
The pancreas is an oblong organ that is situated between the spine and the lower portion of the stomach. In addition to producing insulin and other hormones that assist the body to absorb sugar and regulate blood sugar, it also releases fluids that aid in digestion. Two cell types predominate in the pancreas:
- Enzyme-producing and -releasing exocrine cells that help with meal digestion.
- Endocrine cells are responsible for producing and releasing vital hormones into the blood.
The exocrine cells lining the pancreatic ducts are where the bulk of pancreatic tumors begin. Pancreatic adenocarcinomas are what they are known as.
A pancreatic neuroendocrine tumor (NET) is a type of cancer that develops in pancreatic endocrine cells. This kind of tumor has numerous subgroups. The only other time that pancreatic cancer is mentioned, it only relates to pancreatic adenocarcinoma, not pancreatic NETs.
Pancreatic Cancer Epidemiology
According to estimates from the American Cancer Society, there will be an estimated:
- Pancreatic cancer will be discovered in 62,200 patients.
- The estimated number of deaths from pancreatic cancer is 49,800.
About 3% of cancer cases and 7% of cancer-related deaths in the US are caused by pancreatic cancer. Men are somewhat more likely than women to experience it.
About 1 in 65 people will develop pancreatic cancer in their lifetime. However, certain risk factors may have an impact on a person's likelihood of developing this malignancy.
Pancreatic Cancer Risk Factors
A risk factor is anything that raises your likelihood of getting pancreatic cancer. While some risk factors are modifiable, others are not. The following are the risk factors that raise the likelihood of pancreatic cancer:
- Smoking and tobacco use. Smokers have roughly double the risk of developing pancreatic cancer.
- Obesity. The risk of acquiring pancreatic cancer is increased by 20% if you are extremely overweight (have a high body mass index or BMI).
- Age. After the age of 55, the chance of pancreatic cancer dramatically increases.
- Race. Compared to other ethnic groups, African-Americans have a higher risk of developing pancreatic cancer.
- Family history. Approximately 10% of pancreatic tumors may be caused by hereditary genetic abnormalities. Examples of genetic syndromes that can result in exocrine pancreatic cancer include Lynch syndrome (typically caused by defects in the MLH1 or MSH 2 genes), hereditary pancreatitis brought on by mutations in the PRSSI gene, and hereditary breast and ovarian cancer syndrome brought on by mutations in the BRCA1 or BRCA2 genes.
- Diabetes. The risk of developing pancreatic cancer is higher in people with a prolonged history of type 2 diabetes.
- Chronic pancreatitis. Long-term pancreatic inflammation is associated with a higher chance of developing pancreatic cancer, particularly in smokers.
With the aforementioned risk factors, not everyone develops pancreatic cancer. However, if you have any risk factors, you should talk to your doctor about them.
Pancreatic Cancer Symptoms
Early pancreatic cancer frequently has no visible symptoms at all. By the time they start to exhibit symptoms, they have frequently expanded significantly or spread outside the pancreas.
Even if you have one or more of the symptoms mentioned below, you may not have pancreatic cancer. Other illnesses are more likely to be to blame for many of these symptoms. However, it's crucial to see a doctor if you experience any of these symptoms so that the cause may be identified and, if necessary, addressed.
Yellowing of the skin and eyes (jaundice). Jaundice is frequently one of the earliest signs of pancreatic cancer (and almost always of ampullary cancer).
Bilirubin, a chemical that is produced in the liver and is a dark yellow-brown color, builds up and causes jaundice. Bile is a fluid that the liver normally excretes that contains bilirubin. The common bile duct transports bile into the intestines, where it aids in the breakdown of lipids. The body is eventually left in the stool. Bile cannot reach the intestines when the common bile duct is obstructed, which leads to an accumulation of bilirubin in the body.
The common bile duct is close to cancers that begin in the head of the pancreas. When these tumors are still very small, they can press on the duct and induce jaundice, which can occasionally result in these tumors being discovered at an early stage. However, until the disease has spread throughout the pancreas, malignancies that begin in the body or tail of the pancreas do not impinge on the duct. By this point, cancer frequently has spread outside of the pancreas. The liver is a frequent site of pancreatic cancer metastasis. Jaundice may also result from this. In addition to the skin and eye yellowing, jaundice also manifests as:
- Dark urine. Sometimes, darker urine is the first indication of jaundice. The color of the urine darkens as bilirubin levels rise in the blood.
- Light-colored or greasy stools. Bilirubin typically contributes to the brown color of stools. Gray or light-colored stools could indicate an obstructed bile duct. Additionally, the feces may turn greasy and float in the toilet if bile and pancreatic enzymes that aid in the breakdown of lipids cannot reach the intestines.
- Itchy skin. In addition to turning yellow, the skin may begin to itch when bilirubin levels rise.
Jaundice is not frequently brought on by pancreatic cancer. Other conditions are far more frequent, including gallstones, hepatitis, and other conditions affecting the liver and bile ducts.
Pancreatic cancer frequently causes back or abdominal pain. Cancers that begin in the pancreas' body or tail have the potential to become quite large, start to impinge on adjacent organs, and eventually cause pain. The nerves around the pancreas may also become infected by the malignancy, which frequently results in back pain. Back and abdominal pain is pretty typical, and conditions other than pancreatic cancer are frequently to blame.
People with pancreatic cancer frequently experience unintended weight loss. These individuals frequently have little to no appetite.
Food may have a difficult time passing through the stomach if cancer presses on the far end of it. This may result in a feeling of sickness, vomiting, and pain that gets worse after eating.
Bile can accumulate in the gallbladder and expand it if the malignancy blocks the bile duct. Occasionally, a doctor performing a physical examination will feel this (as a noticeable bump under the right side of the ribcage). Additionally, it appears on imaging tests.
Additionally, pancreatic cancer occasionally causes the liver to enlarge, particularly if the disease has spread there. During an examination, the doctor may feel the edge of the liver beneath the right ribcage, or imaging studies may reveal the huge liver.
A blood clot in a large vein, frequently in the leg, might occasionally be the first indication that someone has pancreatic cancer. A deep vein thrombosis, or DVT, is what this is. The affected leg may experience discomfort, swelling, erythema, and warmth as symptoms. It is possible for a fragment of the clot to occasionally separate and migrate to the lungs, which could make breathing difficult or result in chest pain. A pulmonary embolism, often known as a PE, is a blood clot in the lungs. However, having a blood clot is not typically a sign of cancer. Most blood clots are brought on by other causes.
Rarely, diabetes (high blood sugar) is brought on by pancreatic tumors because they kill the cells that produce insulin. The symptoms can include frequent urination, hunger, and thirst. More frequently than not, cancer can cause subtle changes in blood sugar levels that don't cause diabetic symptoms but can still be found through blood tests.
Pancreatic Cancer Diagnosis
In the early stages of pancreatic cancer, symptoms typically do not manifest. If they do, they can be misinterpreted for signs of a different disease. The pancreas is also located deep within the body, behind several other organs. Without the necessary tools, it is difficult to feel or see because of this. Due to these features, pancreatic cancer is challenging to find.
Pancreatic cancer must often be found and staged using several diagnostic tests. The optimal type of treatment can be selected by your doctors with the aid of accurate diagnosis and staging.
The following examinations may be used to check for pancreatic cancer. These tests may also be used to determine whether cancer has spread and whether the treatment is effective.
Imaging the pancreas and its surrounding is one approach to identifying pancreatic cancer. These tests can be used to find potential cancers, check for tumor spread, and assess the efficacy of treatment. If cancer is found, several imaging tests enable the collection of tissue samples for biopsies. Pancreatic cancer imaging procedures frequently used include:
- CT scan. An image of the pancreas is produced by a series of painless, outpatient CT scans that are obtained at various angles. A CT scan that is specifically designed for imaging the pancreas is the main method for diagnosing and staging pancreatic cancer unless other conditions render its use inappropriate.
- MRI scan. An image of the pancreas is produced using an MRI scan, a painless outpatient technology that uses magnets rather than x-rays. An MRI can occasionally aid in the visualization of cancers that are difficult to see, while CT scans are more frequently used.
- Endoscopic ultrasound. During an endoscopy, a camera attached to a flexible tube called an endoscope is used to allow the doctor to view the inside of the patient's stomach. To view the pancreas on a video screen, a special endoscope with an ultrasound probe is put into the mouth and guided to the first segment of the small intestine. A small piece of tissue can be removed for a biopsy if malignancy is suspected.
- Endoscopic retrograde cholangiopancreatography (ERCP). The first segment of the small intestine is the target of an endoscope that is placed through the mouth. The bile ducts are then entered through the endoscope with a smaller tube. An X-ray is taken after a dye injection through the tube. A small sample of tissue can be removed for a biopsy if malignancy is suspected. A stent may be put on to unblock the ducts if a tumor is blocking them. This might ease digestion issues and stomach pain.
Pancreatic Cancer Biopsy
A tiny piece of tissue is taken out to be examined under a microscope to check for the presence of cancer. While imaging scans can detect pancreatic cancer, a biopsy is nearly always required to provide a definitive diagnosis. For localized pancreatic cancer, samples are typically taken by endoscopic ultrasonography or endoscopic retrograde cholangiopancreatography (ERCP).
A biopsy of the most accessible site is frequently selected for patients with metastatic disease, such as a liver biopsy using CT-guided fine-needle aspiration.
Blood samples can be collected and tested for levels of chemicals that show how well the liver is functioning, such as bilirubin, as well as other organs that could be impacted by pancreatic cancer. Additionally, tumor markers such as CA-19-9 levels in blood samples may be checked. These markers' high concentrations could be a sign of pancreatic cancer. Levels can be used to keep tabs on your therapy.
Pancreatic Cancer Treatment
By definition, pancreatic adenocarcinoma is unresectable if it is deemed to be locally advanced. In this case, neoadjuvant chemotherapy and radiotherapy are usually preferred.
The Whipple technique (pancreaticoduodenectomy) is the preferred procedure if pancreatic cancer is located in the head of the pancreas. The distal resection is required if the tumor is in the body or tail of the pancreas. Patients may undergo radiotherapy, chemotherapy, and 5-FU postoperatively. It is thought that a tumor cannot be removed if the hepatic artery is affected. Resection and vascular reconstruction are required, nevertheless, if the superior mesenteric vein is affected by the tumor. Involvement of the portal vein is similar. It is amenable to resection and graft reconstruction.
Distal pancreatectomy with splenectomy is the preferred surgical treatment when pancreatic cancer is found in the organ's body or tail. If the conditions are met and there is significant celiac and splenic artery involvement, a modified Appleby operation may be used.
Whipple and distal pancreatectomy with splenectomy have both been studied using minimally invasive methods, with similar results in terms of survival, morbidity, and mortality.
Pancreatic Cancer Prognosis
Despite improvements in cancer therapy, the outlook for pancreatic adenocarcinoma remains dismal. The survival rate after five years is around 20 percent. The prognosis is poor one year after diagnosis; 90% of patients pass away after one a few months despite surgery. Palliative surgery, however, may be advantageous.
Pancreatic cancer is a terrible condition. For the majority of patients without the localized disease, there is currently no viable treatment, and 50% of all patients pass away within 6 months after diagnosis. There is no community screening available right now for this cancer.