LDH commonly expressed enzyme in nature and plays a role in anaerobic metabolism.
Detects cellular damage across pathologies including myopathies, myocardial infarction, hemolytic anemias, hepatocellular damage and cancer.
LDH correlates with cancer disease burden and is used as a stratification factor in clinical trials.
It has predictive value in melanoma.
LDH is valuable in monitoring disease telapse in lymphoma.
LDH changes with therapy are associated with survival outcomes in advanced breast, non-small cell lung, hepatocellular, and testicle cancers.
Neutrophil to lymphocytes ratio (NLR): INLR predicts worse outcomes for patients with metastatic prostate cancer, localized or metastatic head and neck cancer, and advanced upper tract urothelial cancers.
A low NLR is associated with longer survival in patients with metastatic melanoma and brain involvement or advanced non-small cell lung cancer treated with PD-1 targeted therapies.
PD-1 increased levels have been associated with prolonged survival in patients with nasopharyngeal carcinoma, as well as improved progression free survival and overall survival in advanced non-small cell lung cancer patients receiving anti-PD-1 antibody therapy or tyrosine kinase inhibitors against epidermal growth factor receptor.
CA 125 has a role in monitoring disease response in epithelial ovarian cancer.
The sensitivity of CA 125 declines in heavily treated ovarian cancer that is resistant to platinum chemotherapy.
Serum PSA is routinely used to assess prostate cancer disease response to therapy.
CEA an adhesion molecules involved in signal transduction within adenocarcinomas.
Increased serum CEA described in breast, colorectal, gastric, lungs, pancreatic, and ovarian malignancies, but can also be observed in benign conditions including inflammatory bowel disease, cigarette smoking, diverticulitis, pancreatitis, liver disease, and alcohol consumption.
Carbohydrate antigen 19-9 is used in pancreatic adenocarcinoma and colorectal cancers with decreasing levels and following treatment and persistence at low levels are used to assess treatment responses to resectable in metastatic disease states.
Circulating tumor cells, persistent through therapy confers an unfavorable prognosis: prostate cancer.
The utility of circulating tumor cells is best demonstrated for monitoring treatment responses by longitudinal sampling within individual patients.
Circulating free DNA( fDNA) has a short half-life in the circulation of approximately four minutes to 2 hours.
Circulating tumor DNA (ctDNA) reflects systemic tumor burden in colorectal cancer, and breast cancer
In patients with metastatic melanoma receiving BRAF/MEK targeted therapy, mutant BRAF V 600 mutation ctDNA has a sensitivity of 70% and a specificity of 100% for detecting progressive disease in patients with an elevated BRAF.
ctRNA, especially miRNAcan be useful as diagnostic, prognostic, and predictive markers in gastrointestinal, hematologic, lung, prostate, and testicle cancers, among others.
In patients with operable urothelial carcinoma patients with detectable ctDNA after surgery had a worse prognosis.
CtDNA is efficacious in following patients with urothelial cancer therapies.
Extracellular vesicles are produced by mammalian cells and are released in humans and can be isolated from malignant ascites or pleural effusions in patients with metastatic cancer and have been detected in saliva, nasal secretions, breast milk, urine and blood.
The miRNA expression of these secretions reflect circulating exosomes that profile tumor tissue samples.
The immune checkpoint molecule PD-L1 exists in circulation on exosomes and changes in response to immunotherapy.