Tumor Markers

Tumor markers can also be called cancer blood tests. Tumor markers are substances produced by cancer cells or produced in response to cancer. Sometimes they also rise in benign diseases. In fact, most tumor markers are also produced in small amounts by healthy cells. However, cancer-specific production is much greater, which is why they are used in the diagnosis and follow-up of cancer. They are not recommended for cancer screening in people without symptoms; a normal result does not rule out cancer. It should not be forgotten, though, that these tests are not 100% reliable; have the screenings recommended by your doctor done according to your age, sex and risk factors.

 

COLORECTAL CANCER

Carcinoembryonic antigen (CEA): CEA levels may be elevated in cancers of the colon, rectum, liver, pancreas, lung (especially small cell), breast, prostate, stomach and ovary. It is particularly useful for monitoring response to treatment and disease progression in colon cancer. The highest CEA levels are seen in colon cancer patients with liver and bone metastases. CEA levels have also been shown to rise in many non-cancer conditions such as smoking, alcohol-related hepatic cirrhosis, pancreatitis, inflammatory bowel disease, emphysema, rectal polyps and benign breast disease.

CA 19-9: Its level rises in all gastrointestinal system cancers (pancreatic cancer, stomach cancer, colon cancer, etc.) and other adenocarcinomas. It is the tumor marker that most frequently rises in pancreatic cancer. It may also rise in benign conditions such as acute and chronic pancreatitis, cholangitis and cirrhosis.

 

LUNG CANCER

Carcinoembryonic antigen (CEA): CEA levels may be elevated in cancers of the colon, rectum, liver, pancreas, lung (especially small cell), breast, prostate, stomach and ovary. It is particularly useful for monitoring response to treatment and disease progression in colon cancer. The highest CEA levels are seen in colon cancer patients with liver and bone metastases. CEA levels have also been shown to rise in many non-cancer conditions such as smoking, alcohol-related hepatic cirrhosis, pancreatitis, inflammatory bowel disease, emphysema, rectal polyps and benign breast disease.

Neuron-Specific Enolase (NSE): It is a type of enolase found in neural tissue, neuroendocrine system cells and APUD (amine precursor uptake and decarboxylation) tissues. NSE is an indicator of tumors of neuroendocrine origin such as small cell lung cancer, neuroblastoma, pheochromocytoma, carcinoids, medullary carcinoma of the thyroid, melanoma and pancreatic islet cell tumors. It is an important indicator especially for small cell cancer of the lung.

ACTH: Cushing's syndrome is the most common endocrine syndrome seen in patients with carcinoma; in half of these patients the tumor is most often oat cell or small cell lung cancer, in 10% thymus, in 10% pancreas, in 5% medullary carcinoma of the thyroid, and in 5% a neural crest tumor. APUDomas, a group of embryonic tumors of endocrine organs, also synthesize ACTH.

Calcitonin: Calcitonin, secreted by the parafollicular C cells of the thyroid, is an ideal tumor marker in medullary thyroid carcinoma arising from these cells. It is useful in monitoring treatment and detecting recurrence. High plasma calcitonin levels are also found in lung (regardless of histological type), colon, breast and pancreatic cancers. Chromogranin A: It is elevated in some neuroendocrine tumors; PPIs, renal failure and atrophic gastritis can cause false elevations. The conditions in which it is used for diagnosis and follow-up are carcinoid tumor, pheochromocytoma, neuroblastoma, endocrine pancreatic tumor and small cell lung cancer. Apart from increases due to tumors, it may also rise in renal failure, liver disease, atrophic gastritis, inflammatory bowel disease, use of stomach-protecting drugs and stress.

 

STOMACH CANCER

Carcinoembryonic antigen (CEA): CEA levels may be elevated in cancers of the colon, rectum, liver, pancreas, lung (especially small cell), breast, prostate, stomach and ovary. It is particularly useful for monitoring response to treatment and disease progression in colon cancer. The highest CEA levels are seen in colon cancer patients with liver and bone metastases. CEA levels have also been shown to rise in many non-cancer conditions such as smoking, alcohol-related hepatic cirrhosis, pancreatitis, inflammatory bowel disease, emphysema, rectal polyps and benign breast disease.

CA 72-4: It is found primarily in adenocarcinomas of the gastrointestinal system and in ovarian and breast tissues. In a large percentage of patients with metastatic stomach cancer, CA 72-4 levels have been shown to be elevated in comparison with CEA or CA 19-9. CA 72-4 levels may also increase in some benign conditions (pancreatitis, cirrhosis, pulmonary diseases, rheumatoid diseases, gynecological diseases, gastrointestinal system diseases, etc.).

CA 19-9: Its level rises in all gastrointestinal system cancers (pancreatic cancer, stomach cancer, colon cancer, etc.) and other adenocarcinomas. It is the tumor marker that most frequently rises in pancreatic cancer. It may also rise in benign conditions such as acute and chronic pancreatitis, cholangitis and cirrhosis.
 

 

PANCREATIC CANCER

Carcinoembryonic antigen (CEA): CEA levels may be elevated in cancers of the colon, rectum, liver, pancreas, lung (especially small cell), breast, prostate, stomach and ovary. It is particularly useful for monitoring response to treatment and disease progression in colon cancer. The highest CEA levels are seen in colon cancer patients with liver and bone metastases. CEA levels have also been shown to rise in many non-cancer conditions such as smoking, alcohol-related hepatic cirrhosis, pancreatitis, inflammatory bowel disease, emphysema, rectal polyps and benign breast disease.

CA 19-9: Its level rises in all gastrointestinal system cancers (pancreatic cancer, stomach cancer, colon cancer, etc.) and other adenocarcinomas. It is the tumor marker that most frequently rises in pancreatic cancer (sensitivity 70-95%). The magnitude of the increase is not related to tumor mass, but the test may be useful in monitoring the course of the disease. It may also rise in benign conditions such as acute and chronic pancreatitis, cholangitis and cirrhosis. In pancreatitis, cholestasis and cirrhosis, CA 19-9 can sometimes rise up to 1000 U/ml; a high value alone does not establish a diagnosis of cancer.

CA 72-4: It is found primarily in adenocarcinomas of the gastrointestinal system and in ovarian and breast tissues. In a large percentage of patients with metastatic stomach cancer, CA 72-4 levels have been shown to be elevated in comparison with CEA or CA 19-9. CA 72-4 levels may also increase in some benign conditions (pancreatitis, cirrhosis, pulmonary diseases, rheumatoid diseases, gynecological diseases, gastrointestinal system diseases, etc.).

Chromogranin A: It is elevated in some neuroendocrine tumors; PPIs, renal failure and atrophic gastritis can cause false elevations. The conditions in which it is used for diagnosis and follow-up are carcinoid tumor, pheochromocytoma, neuroblastoma, endocrine pancreatic tumor and small cell lung cancer. Apart from increases due to tumors, it may also rise in renal failure, liver disease, atrophic gastritis, inflammatory bowel disease, use of stomach-protecting drugs and stress.

 

LIVER CANCER

Carcinoembryonic antigen (CEA): CEA levels may be elevated in cancers of the colon, rectum, liver, pancreas, lung (especially small cell), breast, prostate, stomach and ovary. It is particularly useful for monitoring response to treatment and disease progression in colon cancer. The highest CEA levels are seen in colon cancer patients with liver and bone metastases. CEA levels have also been shown to rise in many non-cancer conditions such as smoking, alcohol-related hepatic cirrhosis, pancreatitis, inflammatory bowel disease, emphysema, rectal polyps and benign breast disease.

Alpha-fetoprotein (AFP): It is used to investigate primary liver, testicular and ovarian cancers and to monitor response to treatment. The main non-cancer source of high AFP levels in adults is benign liver disease. The AFP increase that usually accompanies benign diseases is moderate. Normal value: AFP <8.4 ng/mL.

CA 19-9: Its level rises in all gastrointestinal system cancers (pancreatic cancer, colon cancer, etc.) and other adenocarcinomas. It is the tumor marker that most frequently rises in pancreatic cancer. It may also rise in benign conditions such as acute and chronic pancreatitis, cholangitis and cirrhosis.

CA 15-3: It is used in the diagnosis, recurrence and treatment follow-up of breast cancer patients. It may be useful in predicting disease recurrence and determining response to treatment. In addition to breast cancer, high values may be detected in pancreatic, lung, ovarian, colorectal and liver cancers and in benign liver and breast diseases. Alkaline Phosphatase (ALP): It originates from the liver, bone and placenta. The main sources of ALP found in the serum of normal adults are the liver and bile ducts. It can help detect primary cancers of bone and liver and metastases to these organs. In diseases such as leukemia that spread to the liver, there are marked ALP increases proportional to the extent of liver involvement.

Ferritin: Ferritin, an iron storage protein, has clinical value in disorders of iron metabolism and in some cancers. It is important in acute leukemia, liver cancer and Hodgkin lymphoma. Other causes of increase include blood transfusion, iron therapy, acute and chronic liver diseases, inflammation, and breast, esophageal and head and neck cancers.

 

OVARIAN CANCER

CA 125: It increases in 80-90% of patients with ovarian cancer. Values above the normal range are seen in women in the follicular phase of the menstrual cycle, in the first three months of pregnancy, and in benign diseases such as endometriosis, salpingitis, uterine myoma, cirrhosis, hepatitis and pancreatitis. Increased CA 125 values may also be observed in cancers of other organs such as the breast or lung. It is used to monitor response to treatment in ovarian cancer. Since it also rises in benign conditions, it is not used as a screening test.

Anti-Müllerian Hormone (AMH): AMH, a reliable marker for evaluating ovarian reserve and function, is also used to investigate granulosa cell tumors. In patients operated on for a granulosa cell tumor, it is a highly sensitive marker for demonstrating the effectiveness of surgery in the postoperative period and subsequent disease recurrence.

Inhibins (Inhibin A and B): CA 125 is meaningful for epithelial tumors of the ovary. It is not sensitive enough for investigating granulosa cell tumors. For this, Total Inhibin or Inhibin A + Inhibin B can be measured. Measuring Inhibin together with CA 125 can detect 95% of ovarian cancers.

CA 15-3: In addition to breast cancer, high values may be detected in pancreatic, lung, ovarian, colorectal and liver cancers and in benign liver and breast diseases.

Human Chorionic Gonadotropin (hCG): hCG, which is usually measured to confirm pregnancy and to diagnose ectopic pregnancy, is widely used in the diagnosis and clinical monitoring of gestational trophoblastic pathologies such as hydatidiform mole, choriocarcinoma and placental trophoblastic tumors. Together with AFP, it is also used in the diagnosis and monitoring of some germ cell tumors of the ovary and testis.

 

THYROID CANCER

Thyroglobulin: Thyroglobulin, a storage protein in the thyroid gland, is important in monitoring patients with thyroid cancer, and especially in monitoring patients who have received radioactive iodine therapy or after thyroid surgery. Thyroglobulin is not used for diagnosis; after thyroidectomy or radioactive iodine treatment, it is evaluated together with anti-Tg in the follow-up of recurrence. Other causes of increase include thyroid needle biopsy, thyrotoxicosis, thyroiditis and thyroid adenoma.

Calcitonin: Calcitonin, secreted by the parafollicular C cells of the thyroid, is an ideal tumor marker in medullary thyroid carcinoma arising from these cells. It is useful in monitoring treatment and detecting recurrence. High plasma calcitonin levels are also found in lung (regardless of histological type), colon, breast and pancreatic cancers. However, it is not suitable for screening cancers other than thyroid cancer.

Neuron-Specific Enolase (NSE): It is a type of enolase found in neural tissue, neuroendocrine system cells and APUD (amine precursor uptake and decarboxylation) tissues. NSE is an indicator of tumors of neuroendocrine origin such as small cell lung cancer, neuroblastoma, pheochromocytoma, carcinoids, medullary carcinoma of the thyroid, melanoma and pancreatic islet cell tumors.