Clinical Biochemistry

Clinical biochemistry involves quantifying tumour markers, enzymes, and metabolites in blood and body fluids, helping oncologists navigate the entire patient journey - from the first suspicion of a tumour to long term monitoring following a transplant. Cancer begins at the molecular level within the cell, leading to subtle biochemical changes and morphological abnormalities translating into cellular rebellion and uncontrolled multiplication, invading surrounding tissues. Clinical biochemists monitor the chemical signature of cancer and the body's systemic response to cancer treatment. Tumour markers like PSA help in screening for prostate cancers and by tracking markers like CA 19 9, CA-125 or CEA, the oncologists can assess the response of pancreas, ovarian, liver and colon cancers to treatment long before it becomes visible on imaging modalities like MRI. Enzyme assays like lactate dehydrogenase, Beta2M help in determining the cancer burden. Protein electrophoresis helps biochemists in the diagnosis and monitoring of multiple myeloma by identifying a monoclonal "M-spike" in blood. Advanced biochemical techniques such as serum free light chain assays allow the treating oncologist to detect even tiny amounts of remnant cancer cells that could trigger a relapse. Measuring anti-cancer drug levels in blood allows precise and safe dosing. Baseline and periodic liver function tests and kidney function tests help in calculating the safe and appropriate dose of anti-cancer drugs. Clinical biochemists are the first to spot cancer related life-threatening complications such as tumour lysis syndrome and hypercalcemia of malignancy. In the high-risk environment of a bone marrow transplant (BMT), biochemistry provides the "dashboard" for recovery by monitoring electrolyte homeostasis. Early biochemical shifts in bilirubin or alkaline phosphatase are the first signs of rejection from the new graft. CRP and Procalcitonin detect infection control and steer antibiotic stewardship.