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HCC remains associated with a high mortality rate, in part related to initial diagnosis commonly at an advanced stage of disease. As with other cancers, outcomes are significanty improved if treatment is initiated earlier in the disease process. Because the vast majority of HCC occurs in people with certain chronic liver diseases, especially those with cirrhosis, liver screening is commonly advocated in this population. Specific screening guidelines continue to evolve over time as evidence of its clinical impact becomes available. In the United States, the most commonly observed guidelines are those published by the American Association for the Study of Liver Diseases (AASLD). The AASLD recommends screening people with cirrhosis with ultrasound every 6 months, with or without measurement of blood levels of tumor marker AFP. Elevated levels of AFP are associated with active HCC disease, although inconsistently reliable. At levels >20 sensitivity is 41-65% and specificity is 80-94%. However, at levels >200 sensitivity is 31, specificity is 99%.
On US, HCC often appears as a small hypoechoic lesion with poorly defined margins and coarse irregular internal echoes. When the tumor grows, it can sometimes appear heterogeneous with fibrosis, fatty change, and calcifications. This heterogeneity can look similar to cirrhosis and the surrounding liver parenchyma. A systematic review found that the sensitivity was 60 percent (95% CI 44-76%) and specificity was 97 percent (95% CI 95-98%) compared with pathologic examination of an explanted or resected liver as the reference standard. The sensitivity increases to 79% with AFP correlation.
There remains controversy as to the most effective screening protocols. For example, while there is data to support decreased mortality related to screening in people with hepatitis B infection, the AASLD notes that “there are no randomized trials [for screening] in Western populations with cirrhosis secondary to chronic hepatitis C or fatty liver disease, and thus there is some controversy surrounding whether surveillance truly leads to a reduction in mortality in this population of patients with cirrhosis.”
Methods of diagnosis in HCC have evolved with the improvement in medical imaging. The evaluation of both asymptomatic patients and those with symptoms of liver disease involves blood testing and imaging evaluation. Although historically a biopsy of the tumor was required to prove the diagnosis, imaging (especially MRI) findings may be conclusive enough to obviate histopathologic confirmation.
Many imaging modalities are used to aid in the diagnosis of primary liver cancer. For HCC these include sonography (ultrasound), computed tomography (CT) and magnetic resonance imaging (MRI). When imaging the liver with ultrasound, a mass greater than 2 cm has more than 95% chance of being HCC. The majority of cholangiocarcimas occur in the hilar region of the liver, and often present as bile duct obstruction. If the cause of obstruction is suspected to be malignant, endoscopic retrograde cholangiopancreatography (ERCP), ultrasound, CT, MRI and magnetic resonance cholangiopancreatography (MRCP) are used.
Tumor markers, chemicals sometimes found in the blood of people with cancer, can be helpful in diagnosing and monitoring the course of liver cancers. High levels of alpha-fetoprotein (AFP) in the blood can be found in many cases of HCC and intrahepatic cholangiocarcinoma. Cholangiocarcinoma can be detected with these commonly used tumor markers: carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA) and cancer antigen 125 (CA125). These tumour markers are found in primary liver cancers, as well as in other cancers and certain other disorders.
Prevention of cancers can be separated into primary, secondary, and tertiary prevention. Primary prevention preemptively reduces exposure to a risk factor for liver cancer. One of the most successful primary liver cancer preventions is vaccination against hepatitis B. Vaccination against the hepatitis C virus is currently unavailable. Other forms of primary prevention are aimed at limiting transmission of these viruses by promoting safe injection practices, screening blood donation products, and screening high-risk asymptomatic individuals. Aflatoxin exposure can be avoided by post-harvest intervention to discourage mold, which has been effective in west Africa. Reducing alcohol abuse, obesity, and diabetes would also reduce rates of liver cancer. Diet control in hemochromatosis could decrease the risk of iron overload, decreasing the risk of cancer.
Secondary prevention includes both cure of the agent involved in the formation of cancer (carcinogenesis) and the prevention of carcinogenesis if this is not possible. Cure of virus-infected individuals is not possible, but treatment with antiviral drugs such as interferon can decrease the risk of liver cancer. Chlorophyllin may have potential in reducing the effects of aflatoxin.
Tertiary prevention includes treatments to prevent the recurrence of liver cancer. These include the use of chemotherapy drugs and antiviral drugs.
Upon discovery of a liver tumor, the main issue in the workup is to determine whether the tumor is benign or malignant. Many imaging modalities are used to aid in the diagnosis of malignant liver tumors. For the most common of these, hepatocellular carcinoma (HCC), these include sonography (ultrasound), computed tomography (CT) and magnetic resonance imaging (MRI). When imaging the liver with ultrasound, a mass greater than 2 cm has more than 95% chance of being HCC. The majority of cholangiocarcimas occur in the hilar region of the liver, and often present as bile duct obstruction. If the cause of obstruction is suspected to be malignant, endoscopic retrograde cholangiopancreatography (ERCP), ultrasound, CT, MRI and magnetic resonance cholangiopancreatography (MRCP) are used.
Tumor markers, chemicals sometimes found in the blood of people with cancer, can be helpful in diagnosing and monitoring the course of liver cancers. High levels of alpha-fetoprotein (AFP) in the blood can be found in many cases of HCC and intrahepatic cholangiocarcinoma. Cholangiocarcinoma can be detected with these commonly used tumor markers: carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA) and cancer antigen 125 (CA125). These tumour markers are found in primary liver cancers, as well as in other cancers and certain other disorders..
Ultrasonography of liver tumors involves two stages: detection and characterization. Tumor detection is based on the performance of the method and should include morphometric information (three axes dimensions, volume) and topographic information (number, location specifying liver segment and lobe/lobes). The specification of these data is important for staging liver tumors and prognosis. Tumor characterization is a complex process based on a sum of criteria leading towards tumor nature definition. Often, other diagnostic procedures, especially interventional ones are no longer necessary. Tumor characterization using the ultrasound method will be based on the following elements: consistency (solid, liquid, mixed), echogenicity, structure appearance (homogeneous or heterogeneous), delineation from adjacent liver parenchyma (capsular, imprecise), elasticity, posterior acoustic enhancement effect, the relation with neighboring organs or structures (displacement, invasion), vasculature (presence and characteristics on Doppler ultrasonography and contrast-enhanced ultrasound (CEUS).
Ultrasound is routinely used in the evaluation of cirrhosis. It may show a small and nodular liver in advanced cirrhosis along with increased echogenicity with irregular appearing areas. Other liver findings suggestive of cirrhosis in imaging are an enlarged caudate lobe, widening of the fissures and enlargement of the spleen. An enlarged spleen (splenomegaly), which normally measures less than 11–12 cm in adults, is suggestive of cirrhosis with portal hypertension, in the right clinical context. Ultrasound may also screen for hepatocellular carcinoma, portal hypertension, and Budd-Chiari syndrome (by assessing flow in the hepatic vein).
Cirrhosis is diagnosed with a variety of elastography techniques. Because a cirrhotic liver is generally stiffer than a healthy one, imaging the liver's stiffness can give diagnostic information about the location and severity of cirrhosis. Techniques used include transient elastography, acoustic radiation force impulse imaging, supersonic shear imaging and magnetic resonance elastography. Compared to a biopsy, elastography can sample a much larger area and is painless. It shows a reasonable correlation with the severity of cirrhosis.
Other tests performed in particular circumstances include abdominal CT and liver/bile duct MRI (MRCP).
In FHCC, plasma neurotensin and serum vitamin B12 binding globulin are commonly increased and are useful in monitoring the disease and detecting recurrence.
FHCC has a high resectability rate, i.e. it can often be surgically removed. Liver resection is the optimal treatment and may need to be performed more than once, since this disease has a very high recurrence rate. Due to such recurrence, periodic follow-up medical imaging (CT or MRI) is necessary.
As the tumor is quite rare, there is no standard chemotherapy regimen. Radiotherapy has been used but data is limited concerning its use.
The survival rate for fibrolamellar HCC largely depends on whether (and to what degree) the cancer has metastasized, i.e. spread to the lymph nodes or other organs. Distant spread (metastases), significantly reduces the median survival rate. Five year survival rates vary between 40-90%.
Due to lack of symptoms, until the tumor is sizable, this form of cancer is often advanced when diagnosed. Symptoms include vague abdominal pain, nausea, abdominal fullness, malaise and weight loss. They may also include a palpable liver mass. Other presentations include jaundice, ascites, fulminant liver failure, encephalopathy, gynecomastia (males only), thrombophlebitis of the lower limbs, recurrent deep vein thrombosis, anemia and hypoglycemia.
The usual markers for liver disease - aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase - are often normal or only slightly elevated. FHCC often does not produce alpha fetoprotein (AFP), a widely used marker for conventional hepatocellular carcinoma. It is associated with elevated neurotensin levels.
Diagnosis is normally made by imaging (ultrasound, CT or MRI) and biopsy
The diagnosis of renal medullary carcinoma is typically made after individuals with sickle cell trait present with the typical signs and symptoms outlined above, in combination with radiographic imaging (usually abdominal/pelvic CT scan) studies and ultimately surgical biopsy and pathological examination of the tumor. Findings on radiographic examination are non-specific and can reveal a mass deep within the kidney. Histopathology studies show a distinctive pattern that can be distinguished from other renal tumors.
Gastroscopy (endoscopic examination of the esophagus, stomach, and duodenum) is performed in patients with established cirrhosis to exclude the possibility of esophageal varices. If these are found, prophylactic local therapy may be applied (sclerotherapy or banding) and beta blocker treatment may be commenced.
Rarely are diseases of the bile ducts, such as primary sclerosing cholangitis, causes of cirrhosis. Imaging of the bile ducts, such as ERCP or MRCP (MRI of biliary tract and pancreas) may aid in the diagnosis.
Screens for gastric cancer using photofluorography due to the high incidence there.
The U.S. Preventive Services Task Force (USPSTF) issues recommendations for various cancers:
- Strongly recommends cervical cancer screening in women who are sexually active and have a cervix at least until the age of 65.
- Recommend that Americans be screened for colorectal cancer via fecal occult blood testing, sigmoidoscopy, or colonoscopy starting at age 50 until age 75.
- Evidence is insufficient to recommend for or against screening for skin cancer, oral cancer, lung cancer, or prostate cancer in men under 75.
- Routine screening is not recommended for bladder cancer, testicular cancer, ovarian cancer, pancreatic cancer, or prostate cancer.
- Recommends mammography for breast cancer screening every two years from ages 50–74, but does not recommend either breast self-examination or clinical breast examination. A 2013 Cochrane review concluded that breast cancer screening by mammography had no effect in reducing mortality because of overdiagnosis and overtreatment.
Renal medullary carcinoma is extremely rare and it is not currently possible to predict those individuals with sickle cell trait who will eventually develop this cancer. It is hoped that early detection could result in better outcomes but screening is not feasible.
Chronic liver disease takes several years to develop and the condition may not be recognised unless there is clinical awareness of subtle signs and investigation of abnormal liver function tests.
Testing for chronic liver disease involves blood tests, imaging including ultrasound and a biopsy of the liver. The liver biopsy is a simple procedure done with a fine thin needle under local anaesthesia. The tissue sample is sent to a laboratory where it is examined underneath a microscope.
Drinking may be a cause of earlier onset of colorectal cancer. The evidence that alcohol is a cause of bowel cancer is convincing in men and probable in women.
The National Institutes of Health, the National Cancer Institute, Cancer Research, the American Cancer Society, the Mayo Clinic, and the Colorectal Cancer Coalition, American Society of Clinical Oncology and the Memorial Sloan-Kettering Cancer Center list alcohol as a risk factor.
A WCRF panel report finds the evidence "convincing" that alcoholic drinks increase the risk of colorectal cancer in men at consumption levels above 30 grams of absolute alcohol daily. The National Cancer Institute states, "Heavy alcohol use may also increase the risk of colorectal cancer"
A 2011 meta-analysis found that alcohol consumption was associated with an increased risk of colorectal cancer.
The purpose of screening for viral hepatitis is to identify people infected with the disease as early as possible. This allows for early treatment, which can prevent disease progression, and decreases transmission to others.
Most individuals are asymptomatic and are usually discovered incidentally because of abnormal liver function tests or hepatomegaly noted in unrelated medical conditions. Elevated liver biochemistry is found in 50% of patients with simple steatosis. The serum alanine transaminase level usually is greater than the aspartate transaminase level in the nonalcoholic variant and the opposite in alcoholic FLD (AST:ALT more than 2:1).
Imaging studies are often obtained during the evaluation process. Ultrasonography reveals a "bright" liver with increased echogenicity. Medical imaging can aid in diagnosis of fatty liver; fatty livers have lower density than spleens on computed tomography (CT), and fat appears bright in T1-weighted magnetic resonance images (MRIs). No medical imagery, however, is able to distinguish simple steatosis from advanced NASH. Histological diagnosis by liver biopsy is sought when assessment of severity is indicated.
"DCIS patients and control subjects did not differ with respect to oral contraceptive use, hormone replacement therapy, alcohol consumption or smoking history, or breast self-examination. Associations for LCIS were similar."
The CDC recommends the hepatitis A vaccine for all children beginning at age one, as well as for those who have not been previously immunized and are at high risk for contracting the disease.
For children 12 months of age or older, the vaccination is given as a shot into the muscle in two doses 6–18 months apart and should be started before the age 24 months. The dosing is slightly different for adults depending on the type of the vaccine. If the vaccine is for hepatitis A only, two doses are given 6–18 months apart depending on the manufacturer. If the vaccine is combined hepatitis A and hepatitis B, up to 4 doses may be required.
Hepatic adenoma is usually detected by imaging, typically an ultrasound or CT, as a hyperenhancing liver nodule. Given that several liver tumors appear similarly on these imaging modalities, a multi-phase contrast-enhanced imaging study such as CT or MRI may be used to provide more information. The significance of making a specific diagnosis is that, unlike other benign liver tumors such as hemangioma and focal nodular hyperplasia, hepatic adenomas have a small but meaningful risk of progressing into a malignancy. Although imaging provides supportive information, a definitive diagnosis of hepatic adenoma requires biopsy of the tissue.
A number of liver function tests (LFTs) are available to test the proper function of the liver. These test for the presence of enzymes in blood that are normally most abundant in liver tissue, metabolites or products. serum proteins, serum albumin, serum globulin,
alanine transaminase, aspartate transaminase, prothrombin time, partial thromboplastin time.
Imaging tests such as transient elastography, ultrasound and magnetic resonance imaging can be used to examine the liver tissue and the bile ducts. Liver biopsy can be performed to examine liver tissue to distinguish between various conditions; tests such as elastography may reduce the need for biopsy in some situations.
Genetic counseling and genetic testing are used to confirm that somebody has this gene mutation. Once such a person is identified, early and regular screenings for cancer are recommended for him or her as people with Li–Fraumeni are likely to develop another primary malignancy at a future time (57% within 30 years of diagnosis).
A 2009 revision of the traditional Chompret criteria for screening has been proposed:
A proband who has:
- tumor belonging to the LFS tumor spectrum - soft tissue sarcoma, osteosarcoma, pre-menopausal breast cancer, brain tumor, adrenocortical carcinoma, leukemia or lung bronchoalveolar cancer - before age 46 years;
and at least one of the following:
- at least one first or second degree relative with an LFS tumour (except breast cancer if the proband has breast cancer) before age 56 years or with multiple tumours
- a proband with multiple tumours (except multiple breast tumours), two of which belong to the LFS tumour spectrum and the first of which occurred before age 46 years
- a proband who is diagnosed with adrenocortical carcinoma or choroid plexus tumour, irrespective of family history
Prognosis and treatment is the same as for the most common type of ovarian cancer, which is epithelial ovarian cancer.
The median survival of primary peritoneal carcinomas is usually shorter by 2–6 months time when compared with serous ovarian cancer. Studies show median survival varies between 11.3–17.8 months. One study reported 19-40 month median survival (95% CI) with a 5-year survival of 26.5%.
Elevated albumin levels have been associated with a more favorable prognosis.