Medical Biochemistry

What is Medical Biochemistry?

Biochemistry is the scientific field that studies the chemical substances and processes occurring within living organisms, including humans, animals, plants, and microorganisms. Medical biochemistry, on the other hand, focuses on analyzing tissues, secretions, and bodily fluids at the molecular level to diagnose diseases, understand pathological processes, and differentiate between similar clinical conditions.

In clinical settings, medical biochemistry integrates biochemical analysis results with clinical findings to achieve accurate diagnoses. The positive or negative results obtained from biochemical laboratory tests serve as essential indicators that guide, support, or complement clinical evaluations. Therefore, medical biochemistry is not only a diagnostic tool but an integral component of the entire diagnostic process.

Beyond its diagnostic role, medical biochemistry also plays a critical part in preventive medicine. Through early biochemical evaluations conducted before the onset of symptoms, potential health risks can be detected, allowing preventive measures to be taken in advance. In addition to routine diagnostic and monitoring tests, a wide range of specialized biochemical analyses are performed in medical biochemistry laboratories.

Main Tests Performed in the Medical Biochemistry Department

Hereditary Cancer Genetic Screening

Cancer is a disease that originates from genetic mutations-changes that alter normal cellular function. While most mutations are acquired over a person’s lifetime, a small portion of cancers are hereditary. Both acquired and inherited mutations disrupt cellular growth, differentiation, or death mechanisms, leading to uncontrolled proliferation and, consequently, tumor formation.

The hereditary cancer genetic screening panel evaluates mutations in genes such as PAL, NBN, MUTYH, MSH6, MSH2, MLH1, MEN1, MET, EPCAM, CHEK2, CDH1, CDK4, BRCA2, BRIP1, BMPR1A, BRCA1, ATM, and APC to determine whether an individual carries gene variants associated with cancer risk. For women, the BRCA1 and BRCA2 mutation analysis is particularly important in assessing familial susceptibility to breast and ovarian cancers.

Hereditary cancer testing should not be performed independently without medical consultation. It is recommended when the patient has a first-degree relative diagnosed with cancer, multiple relatives with the same type of cancer, or cancer diagnoses occurring under the age of 50 within the family. Testing decisions should be made in consultation with an oncologist or medical genetics specialist based on the individual’s detailed family history.

Antibody Assays for Immunotherapy Monitoring

Immunotherapy represents one of the most significant advancements in cancer treatment. These therapies utilize the patient’s immune system to target cancer cells. One such treatment is “Racotumomab,” an anti-idiotype vaccine designed to elicit an immune response against the N-Glycol GM3 Ganglioside antigen expressed on lung cancer cells. The medical biochemistry department monitors treatment efficacy in patients receiving Racotumomab by measuring Racotumomab IgG and IgM antibody levels.

Tumor Markers

Tumor markers are measurable substances-proteins, enzymes, antigens, or hormones-found in blood or body fluids that help in cancer screening, diagnosis, classification, monitoring treatment response, and detecting recurrence. Major tumor markers include:

• Nuclear Matrix Protein (NMP-22): Used for diagnosing bladder cancer.

• Calcitonin: Used in diagnosing thyroid cancers.

• Alpha-fetoprotein (AFP): Used in the diagnosis and monitoring of testicular and liver cancers.

• Human Chorionic Gonadotropin (HCG): Monitored in testicular and trophoblastic tumors.

• CA 19-9: Marker associated with pancreatic and gastrointestinal cancers.

• CA 72-4: Marker associated with gastric and intestinal cancers.

• Human Epididymis Protein 4 (HE4) and CA 125: Used for diagnosing ovarian and uterine cancers.

• Carcinoembryonic Antigen (CEA): Used in the diagnosis, staging, and monitoring of gastrointestinal, pancreatic, and gastric cancers.

• Prostate-Specific Antigen (PSA): Used for screening, diagnosing, and monitoring prostate cancer.

Biochemistry and Electrolyte Test Panels

• Fasting and postprandial blood glucose

• ALT (Alanine transaminase)

• GGT (Gamma-glutamyl transferase)

• LDH (Lactate dehydrogenase)

• Glucose tolerance tests

• HDL and LDL cholesterol

• Triglycerides

• Total cholesterol

• Cholinesterase

• CK-MB

• Creatine kinase (CK)

• Calcium

• Magnesium

• Uric acid

• C-reactive protein (CRP)

• Iron-binding capacity

• Total and direct bilirubin

• Electrolytes: sodium, potassium, chloride, lithium, iron, etc.

Hormone and Serology Test Panels

• TSH (Thyroid-stimulating hormone)

• Free T3 and Free T4

• Prolactin

• Insulin

• HCG

• Cortisol

• HOMA-IR

• Troponin I

• ACTH

• HBsAg

• Anti-HIV

• Anti-HCV

• Parathyroid hormone (PTH)

• Vitamin B12

• BNP

• Ferritin

• Homocysteine

• Procalcitonin

• Progesterone

• Testosterone

Neuroinflammatory Panel

• Antinuclear Antibody (ANA)

• Anti-NMDA Receptor Antibody

• Anti-AMPA Receptor Antibody

• ENA Profile

Hematology

• Erythrocyte Sedimentation Rate (ESR)

• Complete Blood Count (CBC)

Coagulation Tests

• Fibrinogen

• D-Dimer

• Activated Partial Thromboplastin Time (aPTT)

• Prothrombin Time (PT)

Urine and Stool Analyses

• 24-hour urine analysis (total protein, creatinine clearance)

• Stool microscopy

• Occult blood test in stool

• Stool parasite examination

• Routine urinalysis

Toxicology Analyses

• Advanced toxicology and confirmatory analysis

• Emergency toxicology testing

Therapeutic Drug Monitoring (TDM)

• Measurement of drug plasma concentrations for dose adjustment and toxicity prevention

Which Conditions Are Evaluated in Medical Biochemistry?

Medical biochemists are responsible for analyzing, validating, and interpreting laboratory test results, ensuring that inaccurate or inconsistent tests are repeated when necessary. They may also manually perform laboratory tests on samples of blood, urine, or other body fluids. In addition, they collaborate with physicians and clinical teams to provide consultative insights regarding biochemical test results, contributing directly to accurate diagnosis and optimized patient care.