A tumor marker is a substance found in your blood, urine, or body tissue. The term “tumor markers” refer to proteins that are made by both healthy cells and cancer cells in the body. It may also refer to mutations, changes, or patterns in a tumor’s DNA. Tumor markers are also called biomarkers.

Doctors may use tumor marker tests to learn if you have cancer. These tests can also help doctors to learn more about your cancer and help to plan treatment.

Cancer and longevity are interconnected, involving genetic, lifestyle, and environmental factors. On one hand, the risk of developing cancer increases with age, but on the other hand, living a long life doesn’t necessarily mean you’ll develop cancer. Here are a few factors to consider:

1. Age as a risk factor: The incidence of cancer increases with age, likely due to the accumulation of genetic damage over time and a decrease in immune system efficiency. Many cancers, including those of the breast, prostate, lung, and colon, are more common in older individuals.

2. Genetic factors: Some individuals might carry genetic variants that predispose them to cancer but also confer other advantages that contribute to longevity. For instance, certain variants in the growth hormone/insulin-like growth factor-1 pathway, while increasing cancer risk, have been associated with increased lifespan in some animal models.

3. Lifestyle factors: Many factors that contribute to a longer, healthier life, such as maintaining a healthy weight, exercising regularly, eating a balanced diet, and not smoking, can also reduce the risk of cancer. For example, smoking cessation reduces the risk of lung and other cancers, and maintaining a healthy weight can decrease the risk of various cancers including breast, colon, and kidney cancers.

4. Cancer survival and longevity: With advancements in early detection and treatment, many people with cancer are living longer. In some cases, they may live long enough to die of other causes rather than cancer. Long-term survival varies by the type and stage of cancer, as well as the person’s overall health and treatment response.

5. Exceptional longevity: Some studies of centenarians (people who live to be at least 100) have found that they often have delayed onset or avoidance of age-related diseases including cancer. It’s suggested that these individuals may have certain genetic and/or lifestyle factors that contribute to both their exceptional longevity and their reduced risk of disease. However, more research is needed to understand these relationships fully.

6. Biological mechanisms: Understanding the biological mechanisms of cancer could also give insights into the biology of aging and vice versa. For example, telomeres, which protect the ends of chromosomes, shorten as cells divide and age. This shortening can lead to cell death or malfunction, contributing to aging and increasing the risk of cancer. Some cancers activate an enzyme called telomerase to extend their telomeres and grow indefinitely, a factor relevant to both cancer and aging research.

In conclusion, the relationship between cancer and longevity is complex, involving genetic, lifestyle, and environmental factors. The same biological processes can have different effects in different contexts, making it a challenging area of research. More studies are needed to fully understand the connections between cancer and longevity, which could lead to improved strategies for cancer prevention and treatment, as well as promoting healthy aging.

14 Analytes Tested

1. Alpha-fetoprotein (AFP)
2. Human chorionic gonadotropin (HCG)
3. Carcinoembryonic antigen (CEA)
4. Neuron-Specific Enolase (NSE)
5. Beta-2-microglobulin (B2M)
6. CA 15-3 (Cancer Antigen 15-3)
7. CA 27.2 (Cancer Antigen 27.29)
8. CA-125 (Cancer Antigen 125)
9. CA 19-9 (Cancer Antigen 19-9)
10. Prostate-specific antigen (PSA) Total
11. Prostate-specific antigen (PSA) Free
12. Calcitonin
13. Thyroglobulin
14. Lactate Dehydrogenase (LDH)

Human chorionic gonadotropin (hCG) is a hormone produced primarily by the placenta during pregnancy. It is the hormone detected in home pregnancy tests, allowing them to determine if a woman is pregnant. In addition to its association with pregnancy, elevated hCG levels can be indicative of certain diseases, including specific types of tumors. Consequently, hCG is also recognized as a tumor marker.

1. Types of Cancer Associated with hCG:
   1. Testicular Cancer: Some testicular cancers, especially certain types of germ cell tumors such as choriocarcinoma and embryonal carcinoma, produce hCG.
   2. Ovarian Cancer: Some ovarian cancers, particularly germ cell tumors like choriocarcinomas and dysgerminomas, can elevate hCG levels.
   3. Others: While less common, certain tumors of the stomach, lung, and pancreas, among others, can produce hCG.
2. Clinical Uses in Oncology:
   1. Diagnosis: Elevated hCG levels, in conjunction with clinical findings and other investigations, can help diagnose certain cancers, especially testicular cancer.
   2. Monitoring: Once a tumor that produces hCG is diagnosed and treated, monitoring hCG levels can provide information about the effectiveness of the treatment, and any potential recurrence of the cancer. Declining levels post-treatment indicate a good response, while persistently elevated or increasing levels can indicate residual or recurrent disease.
   3. Prognosis: In some cases, the amount of hCG produced (tumor burden) can provide information about the stage of the disease and its prognosis.
3. Forms of hCG: In a medical context, it’s essential to understand that there are different forms of hCG (like intact hCG, free beta-hCG, etc.), and specific assays can detect one or more of these forms. The type of assay and the form of hCG it detects can affect interpretation. This test measures total hCG.
4. Limitations:
   1. Specificity: Elevated hCG levels do not always indicate cancer. As mentioned, pregnancy is a primary reason for elevated hCG. Other conditions, including some benign tumors or even marijuana use, can elevate hCG levels.
   2. Sensitivity: Not all tumors, even those types known to produce hCG, will necessarily lead to detectable increases in hCG levels.
5. Interpretation: The absolute level of hCG, its form, and trend (whether it’s rising, stable, or falling) can provide critical information. However, it’s always essential to interpret hCG levels in conjunction with other diagnostic tools, clinical evaluations, and the patient’s history.

In summary, while hCG is known for its role in signaling pregnancy, it is also a vital tumor marker for specific types of cancer. Its measurement can aid in diagnosis, monitoring, and prognosis. However, interpretation requires caution and a comprehensive clinical assessment. If there are concerns about hCG levels in a non-pregnancy context, consultation with an oncologist or appropriate medical specialist is advised.

AFP, or alpha-fetoprotein, is a protein that is normally produced by the liver and yolk sac of a developing fetus during pregnancy. AFP levels decrease soon after birth and are normally low in healthy adults. However, elevated AFP levels can be indicative of certain diseases, including specific types of tumors. As such, AFP is used as a tumor marker, particularly for liver cancer (hepatocellular carcinoma) and certain germ cell tumors.

1. Clinical Uses:
   1. Liver Cancer: AFP is commonly used to monitor individuals at a high risk for hepatocellular carcinoma, such as those with cirrhosis. Elevated AFP levels can suggest the presence of liver cancer, but additional diagnostic methods (like imaging) are essential for confirmation.
   2. Testicular Cancer: AFP, along with other markers like beta-HCG and LDH, can help diagnose and monitor certain types of testicular cancer, mainly non-seminomatous germ cell tumors.
   3. Pregnancy: AFP is part of the maternal serum screening test used during pregnancy to assess the risk of certain congenital anomalies, including neural tube defects and chromosomal abnormalities like Down syndrome.
2. Elevated Levels:
   1. Tumors: Elevated AFP levels can be seen in hepatocellular carcinoma, non-seminomatous testicular cancer, and certain ovarian tumors.
   2. Other Conditions: Elevated AFP levels can also be seen in non-cancerous conditions such as hepatitis, cirrhosis, and other liver diseases.
3. Limitations:
   1. Specificity and Sensitivity: Elevated AFP does not necessarily mean cancer is present. Conversely, not all liver or testicular cancers will produce elevated AFP levels. It’s crucial to interpret AFP values in conjunction with other clinical and diagnostic findings.
   2. Not a Standalone Screening Test: AFP alone should not be used for cancer screening in the general population, but it can be part of regular monitoring for individuals at high risk for liver cancer.
4. Interpretation:
   1. The absolute level of AFP and its trend (whether it’s rising, stable, or falling) can provide important information. A significantly increasing level might be more concerning than a stable or decreasing level.
   2. It’s vital to interpret AFP levels within the broader context of the individual’s clinical picture, including other lab tests, imaging results, and physical examination findings.

In summary, while AFP is a valuable tumor marker for specific types of cancer, it is essential to interpret its levels with caution and in combination with other diagnostic tools and clinical evaluations. If there are concerns about AFP levels or their implications, consultation with an oncologist or appropriate medical professional is advisable.

CEA, which stands for carcinoembryonic antigen, is a protein that is normally present at very low levels in the blood of healthy adults. However, its levels can be elevated in certain types of cancer and other conditions, making it a commonly used tumor marker in oncology.

1. Types of Cancer Associated with CEA:
   1. Colorectal Cancer: CEA is most notably associated with colorectal cancer. It can be used to monitor patients with known colorectal cancer, both for assessing treatment response and for early detection of recurrence.
   2. Other Cancers: Elevated CEA levels can also be seen in other cancers, including breast, lung, pancreatic, stomach, and thyroid cancers. However, it’s not as specific or sensitive for these cancers as it is for colorectal cancer.
2. Clinical Uses:
   1. Monitoring: For patients with known colorectal cancer that has been surgically removed or otherwise treated, regular measurement of CEA can help detect a recurrence. Rising levels may indicate that the cancer has returned or is spreading.
   2. Prognosis: High pre-treatment levels of CEA in patients with colorectal cancer can indicate more advanced disease and may be associated with a poorer prognosis.
   3. Not for Initial Diagnosis: While elevated CEA can suggest the presence of cancer, it is not specific enough to diagnose cancer on its own. It is not typically used for the initial diagnosis of colorectal cancer or any other cancer.
3. Limitations:
   1. Specificity: Many benign conditions can also elevate CEA levels, including inflammatory bowel diseases (like Crohn’s disease or ulcerative colitis), liver diseases, pancreatitis, and smoking.
   2. Sensitivity: Not all patients with colorectal cancer or other cancers will have elevated CEA levels. It’s especially less likely to be elevated in early-stage disease.
4. Interpretation:
   1. It’s essential to interpret CEA levels in the context of the overall clinical scenario. Factors like the patient’s overall health, history of cancer, other lab tests, imaging results, and physical examination findings should be considered.
   2. A single elevated CEA level is not necessarily indicative of cancer recurrence or progression. Trends over time, or a consistent increase in levels, are more concerning and might warrant further investigation.

In summary, CEA is a valuable tool in the oncological setting, especially for monitoring colorectal cancer. Still, it has limitations and needs to be used and interpreted judiciously in conjunction with other clinical and diagnostic information. If there are concerns about CEA levels or their implications, consultation with an oncologist or appropriate medical professional is essential.

Neuron-Specific Enolase (NSE) is an enzyme that is found predominantly in neurons and cells of the neuroendocrine system. Because of its tissue-specific presence, it’s used as a marker for neurons and cells with neuroendocrine differentiation. In the context of oncology, elevated levels of NSE in the blood can be indicative of certain types of tumors.

1. Types of Cancer Associated with NSE:
   1. Small Cell Lung Cancer (SCLC): NSE is one of the tumor markers that can be elevated in patients with SCLC, a type of aggressive lung cancer. It’s used for diagnosis, monitoring treatment response, and detecting disease recurrence.
   2. Neuroblastoma: This is a type of cancer that arises in immature nerve cells and most commonly affects young children. Elevated NSE levels can be seen in patients with neuroblastoma.
   3. Other Neuroendocrine Tumors: Other tumors originating from neuroendocrine cells, such as certain types of pancreatic tumors, can also lead to increased NSE levels.
2. Clinical Uses:
   1. Diagnosis: While elevated NSE can suggest the presence of a neuroendocrine tumor, it cannot provide a definitive diagnosis on its own. It should be combined with other diagnostic tools and tests.
   2. Monitoring: In patients with known neuroendocrine tumors, particularly SCLC, periodic measurement of NSE can help assess the effectiveness of treatment and detect recurrence.
   3. Prognosis: In some cancers, particularly SCLC, very high levels of NSE at the time of diagnosis can be associated with a more aggressive disease and a poorer prognosis.
3. Limitations:
   1. Specificity: Elevated NSE levels can also be seen in non-cancerous conditions. For example, certain neurological diseases, traumatic brain injury, or even hemolysis (rupture of blood cells) during the collection of a blood sample can lead to increased NSE levels.
   2. Sensitivity: Not all patients with SCLC or other neuroendocrine tumors will have elevated NSE levels. Moreover, its levels might not always reflect tumor burden accurately, so relying on it solely can be misleading.
4. Interpretation: As with many tumor markers, interpreting NSE levels requires considering the broader clinical context. The patient’s overall health, history, other lab tests, imaging results, and physical examination findings should be taken into account.

In summary, NSE is a valuable marker in the context of neuroendocrine tumors and specific conditions related to neural tissues. Still, its limitations necessitate its careful use and interpretation in conjunction with other clinical and diagnostic tools. Consultation with an oncologist or relevant medical specialist is crucial when interpreting and acting on NSE levels.

Beta-2 Microglobulin (B2M) is a component of the major histocompatibility complex (MHC) class I molecules, which are present on the surface of almost all cells in the body. B2M plays a crucial role in presenting peptides to the immune system. In clinical medicine, B2M is measured primarily in the blood, but it can also be measured in the cerebrospinal fluid (CSF) and in urine. 

1. Clinical Implications of Elevated B2M:
   1. Multiple Myeloma: Elevated levels of B2M in the blood can be indicative of multiple myeloma, a type of blood cancer. It is not only helpful for diagnosis but also for staging and prognostication. Higher levels often correlate with a more advanced disease and a poorer prognosis.
   2. Chronic Lymphocytic Leukemia (CLL): Elevated B2M levels can be seen in CLL and are associated with a more aggressive disease course.
   3. Lymphoma: Some types of lymphomas can also show elevated B2M levels.
   4. Kidney Disease: The kidneys typically filter B2M from the blood, and it’s excreted in the urine. Elevated levels of B2M in the urine can indicate kidney disease, especially diseases of the renal tubules.
2. Other Clinical Uses:
   1. HIV: Elevated B2M levels can be seen in patients with HIV and may indicate disease progression.
   2. Systemic Inflammatory Conditions: Diseases like systemic lupus erythematosus (SLE) can show increased B2M levels.
3. Limitations:
   1. Specificity: While an elevated B2M level can indicate a medical issue, it is not specific to any single disease. Other tests and clinical evaluations are essential to arrive at a definitive diagnosis.
   2. Variability: Levels of B2M can vary depending on factors like age and kidney function. For instance, older individuals and those with impaired kidney function might have naturally elevated B2M levels.
4. Interpretation: As always, interpreting the levels of B2M requires a comprehensive assessment of the patient’s clinical picture. It’s crucial to consider other lab tests, symptoms, clinical evaluations, and imaging studies when interpreting B2M levels.

In summary, B2M is a protein with a role in immune system function. Its levels in blood or other body fluids can provide valuable information about various conditions, especially certain cancers and kidney diseases. However, interpretation needs a broad clinical context, and consultation with relevant medical specialists is essential when evaluating elevated B2M levels.

CA-125, or Cancer Antigen 125, is a protein that can be found on the surface of many ovarian cancer cells, as well as in the blood of some individuals with ovarian cancer. It’s the most frequently tested tumor marker for ovarian cancer.

1. Clinical Uses:
   1. Detection: While CA-125 is associated with ovarian cancer, it is not recommended for general population screening due to its lack of specificity. However, it might be used as part of the evaluation for women who have symptoms suggestive of ovarian cancer or for those with a strong family history of ovarian and/or breast cancer.
   2. Monitoring: CA-125 is commonly used to monitor the response to treatment in women diagnosed with ovarian cancer. A decreasing level can indicate that the cancer is responding to treatment, while increasing levels might suggest a lack of response or recurrence.
2. Limitations:
   1. Not Specific to Ovarian Cancer: Elevated CA-125 levels can be seen in conditions other than ovarian cancer, including menstruation, pregnancy, pelvic inflammatory disease, endometriosis, fibroids, liver disease, and other cancers such as endometrial or fallopian tube cancer.
   2. Not All Ovarian Cancers Produce CA-125: Approximately 20% of ovarian cancers, especially early-stage tumors, do not produce elevated levels of CA-125.
3. CA-125 and High-Risk Populations: In women with a strong family history of ovarian cancer or known genetic mutations that increase the risk (e.g., BRCA mutations), CA-125 levels combined with transvaginal ultrasound might be used for routine surveillance.
4. Interpretation: While a single elevated CA-125 result can be concerning, it’s vital to interpret the results in the context of the overall clinical picture. Elevated levels on their own do not confirm cancer. Additional evaluations, including imaging and sometimes surgical exploration, are essential for a definitive diagnosis.
5. Other Uses: CA-125 can sometimes be used in the diagnosis and monitoring of other gynecological cancers or conditions, but its primary association is with ovarian cancer.

In conclusion, while CA-125 is an essential tool in the management and detection of ovarian cancer, its limitations mean it must be used as part of a broader diagnostic approach. If there are concerns related to CA-125 levels or ovarian cancer risk, consultation with a gynecologic oncologist or another appropriate medical specialist is recommended.

CA 15-3 (Cancer Antigen 15-3) is a tumor marker that is primarily associated with breast cancer. The protein CA 15-3 is found on the surface of breast cancer cells and can be detected in the blood when shed from the tumor. It’s one of the molecules used in the assessment and monitoring of certain diseases, particularly breast cancer.

1. Clinical Uses:
   1. Monitoring: CA 15-3 is primarily utilized to monitor patients with a known diagnosis of breast cancer. It can be used to gauge how a patient is responding to treatment and for monitoring potential recurrence after treatment has concluded.
   2. Not for Initial Diagnosis: CA 15-3 is not typically used for the initial diagnosis of breast cancer. This is because it lacks sufficient specificity and sensitivity, especially for early-stage disease.
2. Elevated Levels:
   1. Breast Cancer: A rise in CA 15-3 levels can suggest the presence or recurrence of breast cancer, particularly in more advanced stages.
   2. Other Conditions: Elevated levels can also occur in other conditions, both malignant and benign. This includes other types of cancers, liver diseases, and certain benign breast disorders.
3. Limitations:
   1. Specificity and Sensitivity: While CA 15-3 can be elevated in breast cancer, it’s not exclusive to this disease. Its sensitivity is also limited, meaning not all breast cancer patients will show elevated CA 15-3 levels. Conversely, elevated levels don’t confirm the presence of cancer without other supporting evidence.
   2. Not for Screening: Given its limited specificity and sensitivity, CA 15-3 is not employed as a breast cancer screening tool in the general population.
4. Interpretation:
   1. Context is essential. Results from a CA 15-3 test should be interpreted in tandem with other diagnostic tools and within the broader clinical scenario. A single elevated result doesn’t definitively diagnose cancer.
   2. CA 15-3 might be used in combination with other tumor markers or diagnostic methods to provide a more comprehensive understanding of a patient’s condition.

In summary, CA 15-3 plays a role in the management and monitoring of breast cancer, aiding in assessing treatment response and checking for recurrence. However, its limitations mean it must be utilized in combination with other diagnostic tools and clinical assessments. If there are concerns related to CA 15-3 levels or their implications, consultation with an oncologist or another appropriate medical specialist is recommended.

CA 27.29 is a tumor marker that’s primarily associated with breast cancer. It’s one of the molecules shed into the blood from tumor cells. While CA 27.29 can be elevated in breast cancer, it is not exclusively linked to this disease.

1. Use in Clinical Practice:
   1. Monitoring: CA 27.29 is primarily used to monitor patients with a known diagnosis of breast cancer. It can help assess how a patient is responding to treatment and monitor for cancer recurrence after treatment.
   2. Not for Initial Diagnosis: Due to its lack of specificity and sensitivity, especially in early-stage disease, CA 27.29 is not used for the initial diagnosis of breast cancer.
2. Elevated Levels:
   1. Breast Cancer: Elevated levels of CA 27.29 can indicate the presence of breast cancer, particularly in more advanced stages or if the disease has recurred.
   2. Other Conditions: Elevated CA 27.29 levels can also be seen in other cancers and benign conditions, including ovarian cancer, colon cancer, and certain liver diseases.
3. Limitations:
   1. Not Specific: CA 27.29 is not specific to breast cancer. Many benign conditions and other cancers can elevate its levels, which means it should not be used alone to determine the presence or recurrence of breast cancer.
   2. Not Sensitive: Not all breast cancers will produce elevated CA 27.29 levels, especially in early stages. Relying solely on this test can miss some cases.
4. Combination with Other Markers: CA 27.29 might be used in conjunction with other tumor markers, like CA 15-3, to increase the likelihood of detecting breast cancer recurrence.
5. Interpretation: As with other tumor markers, it’s essential to interpret the results of the CA 27.29 test in the broader context of the overall clinical picture. A healthcare professional should consider other diagnostic methods and the patient’s medical history when interpreting results.

In conclusion, while CA 27.29 can be a useful tool in managing breast cancer, especially in monitoring treatment response and checking for recurrence, it should be used judiciously and in combination with other diagnostic tools and clinical evaluations.

CA 19.9 (Cancer Antigen 19.9) is a tumor marker that is primarily associated with pancreatic and biliary (gallbladder and bile duct) cancers. It is a carbohydrate antigen expressed on the surface of cells and can be released into the blood, where it can be detected using specific assays.

1. Clinical Uses:
   1. Monitoring: CA 19.9 is most commonly used to monitor patients with a known diagnosis of pancreatic or biliary cancer. It can help in assessing the effectiveness of treatments, tracking the progress of the disease, and checking for recurrence after treatment.
   2. Not for Initial Diagnosis: While elevated CA 19.9 levels can suggest the presence of pancreatic or biliary cancer, the test is not specific enough to be used for the initial diagnosis. It can be elevated in other conditions as well.
2. Elevated Levels:
   1. Pancreatic and Biliary Cancers: Elevated CA 19.9 levels are often seen in patients with pancreatic or biliary tract cancers, especially in advanced stages.
   2. Other Conditions: Elevated CA 19.9 levels can also be observed in non-cancerous conditions, including pancreatitis, liver disease, and conditions related to the bile ducts. Other cancers, such as colorectal or stomach cancer, can also elevate CA 19.9 levels.
3. Limitations:
   1. Specificity and Sensitivity: Not all patients with pancreatic or biliary cancer will have elevated CA 19.9 levels. Conversely, an elevated CA 19.9 doesn’t necessarily confirm the presence of cancer. It’s crucial to combine the test with other diagnostic methods.
   2. Not a Screening Test: Due to its lack of specificity, CA 19.9 is not recommended as a screening test for cancer in the general population.
4. Interpretation:
   1. CA 19.9 levels should always be interpreted in the context of the overall clinical picture. Factors like other diagnostic test results, symptoms, and medical history should be taken into account.
   2. Some individuals, due to their genetic makeup, cannot produce the CA 19.9 antigen, even if they have a tumor. Such individuals are known to be “non-expressers.”

In conclusion, while CA 19.9 can play a crucial role in monitoring known cases of pancreatic or biliary cancers, it has limitations that require careful interpretation in the clinical context. If there are concerns about CA 19.9 levels or their implications, consultation with an oncologist or another appropriate medical professional is crucial.

PSA stands for Prostate-Specific Antigen. It is a protein produced by the prostate gland and can be detected in the blood. The PSA test measures the concentration of PSA in the blood, and it is primarily used as a screening tool for prostate cancer.

1. Prostate Cancer Screening: The primary use of the PSA test is to screen for prostate cancer. An elevated PSA level might suggest the presence of prostate cancer, but it’s not definitive.
2. Monitoring Prostate Cancer: In men diagnosed with prostate cancer, PSA levels can be used to monitor disease progression, assess the effectiveness of treatment, and detect recurrence.
3. Benign Conditions:
   1. Elevated PSA levels can also be due to benign (non-cancerous) conditions, such as:
      1. Benign prostatic hyperplasia (BPH) – an enlargement of the prostate gland that is not cancerous.
      2. Prostatitis – inflammation or infection of the prostate gland.
4. Factors Influencing PSA Levels:
   1. Age: PSA levels tend to increase with age.
   2. Ejaculation: It can temporarily raise PSA levels.
   3. Medications: Some drugs, like finasteride and dutasteride, which are used to treat BPH, can lower PSA levels.
   4. Prostate Procedures: Procedures like biopsies or the placement of a catheter can increase PSA levels.
5. Controversies and Recommendations: Different medical organizations have various recommendations regarding PSA screening. It’s generally advised that men discuss the risks and benefits of PSA screening with their doctor to make an informed decision.
6. PSA Velocity and Density:
   1. PSA Velocity: Refers to the rate of change in PSA levels over time. A rapid rise might be more suggestive of cancer, especially aggressive forms.
   2. PSA Density: Considers the PSA level relative to the size of the prostate (as measured typically by ultrasound). A higher PSA density can be more suggestive of cancer.
7. Free vs. Total PSA:
   1. PSA exists in the blood in two main forms: bound to other proteins or free (not bound). A PSA test can measure the total PSA or the ratio of free to total PSA.
   2. A lower percentage of free PSA might suggest a higher risk of prostate cancer.

In summary, while the PSA test is a valuable tool in the diagnosis and monitoring of prostate cancer, its interpretation requires a comprehensive approach. Other factors, such as age, prostate size, and individual risk factors, must be considered. If you or someone you know is considering a PSA test or has questions about the results, it’s crucial to consult with a urologist or an oncologist.

Calcitonin is a hormone produced by the parafollicular cells (also called C cells) of the thyroid gland. It plays a role in calcium and bone metabolism.

1. Physiological Role:
   1. Calcium Regulation: Calcitonin helps regulate calcium levels in the blood. When blood calcium levels are high, calcitonin is released to help lower it. It does this by inhibiting osteoclast activity in the bones, which reduces bone resorption and, consequently, the release of calcium from bones into the bloodstream.
2. Medullary Thyroid Cancer (MTC):
   1. Tumor Marker: Calcitonin is used as a tumor marker for medullary thyroid cancer (MTC). MTC originates from the parafollicular C cells of the thyroid gland. A significant increase in calcitonin levels can be indicative of MTC.
   2. Monitoring and Prognosis: Once diagnosed with MTC, calcitonin levels can be used to monitor the effectiveness of treatment and detect recurrence.
3. Calcitonin Test:
   1. Purpose: A blood test can measure the level of calcitonin in the blood. It may be used to diagnose MTC, especially in individuals with a family history of the disease or those with other risk factors.
   2. Interpretation: Elevated calcitonin levels might suggest the presence of MTC, but other factors and tests should be considered for a definitive diagnosis.
4. Calcitonin as a Therapeutic Agent:
   1. Osteoporosis: Synthetic calcitonin, often given as a nasal spray or injection, has been used to treat osteoporosis. By inhibiting osteoclast activity, calcitonin can help reduce bone loss. However, it’s worth noting that other medications have largely supplanted calcitonin in the treatment of osteoporosis due to concerns about potential side effects and because newer treatments have been found to be more effective.
5. Side Effects of Calcitonin Treatment:
   1. Allergic Reactions: Especially when given as a salmon-derived formulation.
   2. Nausea: Particularly with higher doses or initial therapy.
   3. Nasal Irritation: When using the nasal spray form.
   4. There have been concerns about a potential increased risk of cancer with long-term use of calcitonin, but the evidence is not conclusive.

In summary, calcitonin is a hormone related to calcium and bone metabolism. It is of particular clinical importance in the context of medullary thyroid cancer and has therapeutic uses in conditions like osteoporosis. As always, medical decisions regarding calcitonin testing or treatment should be made in consultation with appropriate healthcare professionals.

Thyroglobulin is a protein produced and used by the thyroid gland to produce the thyroid hormones thyroxine (T4) and triiodothyronine (T3).

1. Physiology: Thyroid Hormone Precursor: Thyroglobulin serves as a precursor for the production of thyroid hormones. Iodine is added to specific tyrosine residues on thyroglobulin, which then undergoes enzymatic conversion to produce T3 and T4. The hormones are released into the bloodstream when needed by proteolytic cleavage from thyroglobulin.
2. Thyroglobulin as a Tumor Marker:
   1. Differentiated Thyroid Cancers: Thyroglobulin is used as a tumor marker primarily for differentiated thyroid cancers (papillary and follicular thyroid cancers). Following the surgical removal of the thyroid (thyroidectomy) and any subsequent radioactive iodine (RAI) therapy, serum thyroglobulin levels should be very low or undetectable.
   2. Monitoring and Prognosis: If thyroglobulin levels rise after treatment, it might indicate the recurrence or persistence of thyroid cancer. Regular measurement of thyroglobulin is standard in the follow-up care of patients with differentiated thyroid cancer.
3. Thyroglobulin Antibodies:
   1. Autoimmune Thyroid Diseases: Some people produce antibodies against thyroglobulin (anti-thyroglobulin antibodies). These antibodies can be present in conditions like Hashimoto’s thyroiditis or Graves’ disease.
4. Interference: The presence of anti-thyroglobulin antibodies can interfere with the measurement of thyroglobulin in the blood, potentially leading to falsely low or undetectable levels. Therefore, in patients with differentiated thyroid cancer, it’s common to measure both thyroglobulin and anti-thyroglobulin antibodies.
5. Thyroglobulin Test:
   1. Purpose: A blood test can measure the level of thyroglobulin in the blood. It’s primarily used to monitor patients with differentiated thyroid cancer after treatment but may also be used in the diagnostic evaluation of thyroid nodules or goiters.
   2. Interpretation: As mentioned, elevated thyroglobulin levels might suggest the presence or recurrence of differentiated thyroid cancer, especially in those who have had their thyroid removed. However, other factors, like the presence of anti-thyroglobulin antibodies, need to be considered.

In summary, thyrolobulin is an essential protein in the synthesis of thyroid hormones and serves as a clinically relevant tumor marker in certain thyroid cancers. If you or someone you know is considering a thyroglobulin test or has questions about the results, it’s vital to consult with an endocrinologist or an oncologist.

Lactate Dehydrogenase (LDH) is an enzyme found in many body tissues, including the liver, heart, muscles, kidneys, brain, and lungs. It plays a crucial role in the conversion of lactate to pyruvate, a step in producing energy for cells.

LDH can be elevated in many conditions, not just cancer. However, in the context of malignancies:

1. General Marker: LDH is a non-specific tumor marker, meaning its elevation can be seen in a variety of cancers, but it’s not specific to any particular type. Elevated LDH levels in the bloodstream might indicate cellular damage, including damage caused by rapidly growing tumors.
2. Types of Cancers: Elevated LDH levels are often seen in:
   1. Lymphoma
   2. Leukemia
   3. Germ cell tumors
   4. Melanoma
   5. Other solid tumors
3. Prognostic Value: In some cancers, particularly lymphomas and melanoma, a high LDH level at diagnosis or an increasing level during treatment might indicate a poorer prognosis.
4. Monitoring Treatment: LDH can sometimes be used to monitor the effectiveness of treatment. If the level drops following therapy, it might suggest the treatment is working. Conversely, if it remains elevated or increases, it could indicate persistent or progressing disease.
5. Differential Isoenzymes: LDH exists in different forms, called isoenzymes. There are five major types (LDH-1 to LDH-5), and they are distributed differently among body tissues. For instance, LDH-1 is primarily found in the heart, while LDH-5 is most abundant in the liver and muscles. Analyzing the pattern of these isoenzymes can sometimes give clues about the source of an elevation. However, this is often of more value in non-cancerous conditions, such as distinguishing between a heart attack and some other cause of chest pain.
6. Non-cancerous Elevation: It’s essential to note that many non-cancerous conditions can also lead to elevated LDH levels, including heart failure, liver disease, hemolysis (breaking open of red blood cells), muscle injury, and certain lung conditions (like pulmonary embolism).

In summary, while LDH can be used as a tumor marker, it’s non-specific. An elevated LDH level might indicate the presence or progression of certain cancers, but it can also be raised due to numerous other non-cancerous conditions. As always, any concerns regarding LDH levels or potential signs of cancer should be discussed with a healthcare provider.

• SST tube of blood
• Urine

7 – 10 days

Price: $349.00