From the Guidelines
In the initial evaluation of malignancy, a comprehensive approach including complete blood count, comprehensive metabolic panel, lactate dehydrogenase (LDH), and cancer-specific markers such as CA 15-3, CA 27.29, CEA for breast cancer, PSA and free PSA for prostate cancer, CEA, CA 19-9, and AFP for gastrointestinal malignancies, and CA-125, HE4, and the ROMA index for ovarian cancer is recommended. The choice of tumor marker panels depends on the suspected cancer type. For instance, ovarian cancer assessment benefits from the OVA1 panel, which includes CA125, prealbumin, apolipoprotein A1, β2-microglobulin, and transferrin, as noted in a study published in Nature Protocols 1.
Cancer-Specific Markers
- For suspected breast cancer, CA 15-3, CA 27.29, and CEA are valuable markers.
- Prostate cancer evaluation should include PSA and free PSA.
- For gastrointestinal malignancies, CEA, CA 19-9, and AFP are recommended, with CA 19-9 being a good diagnostic marker for pancreatic cancer, as stated in the NCCN clinical practice guidelines in oncology 1.
- Ovarian cancer assessment benefits from CA-125, HE4, and the ROMA index, although the NCCN Panel does not currently recommend the use of these biomarkers for determining the status of an undiagnosed pelvic mass, as mentioned in the Journal of the National Comprehensive Cancer Network 1.
- Testicular cancer evaluation should include AFP, beta-hCG, and LDH.
Interpretation of Tumor Markers
It's crucial to interpret tumor markers in conjunction with clinical findings, imaging studies, and histopathological examination, as elevated levels can sometimes occur in benign conditions, and normal levels don't necessarily exclude malignancy. The NCCN guidelines emphasize the importance of identifying biomarkers for early detection and surveillance of cancers, such as pancreatic adenocarcinoma, where CA 19-9 is recognized as a valuable biomarker 1.
Recent Evidence
A recent study published in Nature Protocols highlights the success of biomarker development, including the OVA1 panel for ovarian cancer, which was discovered using surface-enhanced laser desorption ionization (SELDI)-time of flight (TOF) MS 1. However, it's essential to consider the limitations and potential false positives of these markers, as noted in various studies, including those on ovarian cancer screening 1.
Clinical Practice
In clinical practice, the measurement of serum CA 19-9 levels is recommended before surgery, after surgery, and for surveillance in pancreatic cancer, as per the NCCN guidelines 1. Similarly, other cancer-specific markers should be used judiciously, taking into account their sensitivity, specificity, and potential for false positives or negatives. By combining these markers with comprehensive clinical evaluations, healthcare providers can improve the diagnosis, staging, and monitoring of malignancies, ultimately enhancing patient outcomes.
From the Research
Tumor Markers for Malignancy Evaluation
The following tumor markers are useful in the initial evaluation of malignancy:
- Prostate-specific antigen (PSA) for prostate cancer 2
- CA 125 for ovarian cancer 2
- Human chorionic gonadotrophin (hCG) for trophoblastic disease and nonseminomatous testicular germ cell tumors 2
- Alpha-foetoprotein (AFP) for nonseminomatous testicular germ cell tumors 2
- Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) for pancreatic cancer 3, 4, 5
- CA 125 for pancreatic cancer 4, 5
- CA 242 for pancreatic cancer 5
Panels of Tumor Markers
Panels of tumor markers can be useful in the initial evaluation of malignancy, including:
- PSA and digital rectal examination for prostate cancer 2
- CA 125 and ultrasound for ovarian cancer 2
- CEA and CA19-9 for pancreatic cancer 3, 4, 5
- CA19-9, CEA, CA125, and CA242 for pancreatic cancer 5
Clinical Usefulness of Tumor Markers
Tumor markers can be used in the clinical evaluation of malignancy, including: