Increased Serum CA-15.3 Levels in Patients with Megaloblastic Anemia due to Vitamin B12 Deficiency

Factors influencing blood tumor marker concentrations in the absence of neoplasia

BACKGROUND

Tumor markers (TMs) are a heterogeneous group of molecules used in the diagnosis, prognosis and follow-up of cancer patients. During neoplastic differentiation, cells can either directly synthesize or induce the synthesis of TMs, and the release of these molecules into the bloodstream allows their quantification in biological fluids. Although very small concentrations of TMs are usually present in the serum or plasma of healthy subjects, increased concentrations may also be found in the presence of benign diseases or due to technical interference, producing false positive results.

MATERIAL AND METHODS AND RESULTS

Our review analyses the causes of false positives described between January 1970 to February 2023 for the TMs most frequently used in clinical practice: α-fetoprotein (AFP), β2-microglobulin (β2-M), cancer antigen 15-3 (CA 15-3), cancer antigen CA 19-9 (CA 19-9), cancer antigen CA 72-4 (CA 72-4), cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), chromogranin A (CgA), choriogonadotropin (hCG), cytokeratin 19 fragment (CYFRA 21-1), neuron-specific enolase (NSE), human epididymis protein 4 (HE4), serum HER2 (sHER2), squamous cell carcinoma antigen (SCCA), protein induced by vitamin K absence-II (PIVKA-II), Pro-gastrin-releasing peptide (Pro-GRP), prostate-specific antigen (PSA), Protein S-100 (S-100) and thyroglobulin (Tg). A total of 247 references were included.

CONCLUSIONS

A better understanding of pathophysiological processes and other conditions that affect the concentration of TMs might improve the interpretation of results and their clinical application.

Vitamin B12 and folic acid associated megaloblastic anemia: Could it mislead the diagnosis of breast cancer?

CA 15-3 is a tumor-associated antigen and is overexpressed in breast tumors, and may also be high in some other non-cancerous conditions. The aim of this study was to investigate the effect of megaloblastic anemia due to vitamin B12 or folic acid deficiency on the levels of tumor markers. Five-year patient data were retrospectively analyzed. The associations between megaloblastic anemia due to vitamin B12 deficiency and CA 15-3, CA 125, CA 19-9, CEA, and AFP levels were analyzed. Furthermore, association between CA 15-3 level and megaloblastic anemia due to folic acid deficiency was evaluated. Median CA 15-3 level was 38.1 U/mL in the group with megaloblastic anemia due to vitamin B12 deficiency(n = 15), 46.7 U/mL in the group with megaloblastic anemia related to folic acid deficiency (n = 3), and 17.8 U/mL in the normal group(n = 1724). CA 15-3 levels were significantly higher among patients with vitamin B12- and folic acid-associated megaloblastic anemia compared to the normal group (p = 0.001 and p = 0.005, respectively). Megaloblastic anemia due to vitamin B12 deficiency was not associated with any significant differences in CA 125, CA 19-9, CEA, or AFP levels compared to the normal group (p = 0.777, p = 0.327, p = 0.577, and p = 0.197, respectively). The numbers of anemic and normal subjects compared in these tests were 12 vs. 1501, 17 vs. 1827, 4 vs. 897, and 8 vs. 1041, respectively. In conclusion, megaloblastic anemia results in ineffective erythropoiesis, and increased levels of CA 15-3 may be associated with this issue. Clinicians should take this into account when evaluating for a pre-diagnosis of breast cancer.

CA 15-3 predicting breast cancer relapse: beware of vitamin B12 deficiency

A sustained increase of cancer antigen 15-3 serum levels was found in a 54-year-old woman treated 2 years ago for early stage breast cancer, without any evidence of cancer recurrence. The patient thereafter developed severe megaloblastic anemia secondary to vitamin B12 deficiency. Supplementation with B12 to reverse the anemia led to the normalization of the cancer antigen 15-3 serum levels. As such, with the limited understanding of molecular biology, the integrative approach of clinical history, physical examination, and diagnostic imaging remain pivotal in the management of cancer patients.

Postoperative elevation of CA15-3 due to pernicious anemia in a patient without evidence of breast cancer recurrence

Cancer antigen 15-3 (CA15-3) is considered as a marker for breast cancer recurrence. However, we encountered a case where the patient showed postoperative elevation of the CA15-3 level due to pernicious anemia without evidence of breast cancer recurrence. The patient was a 60-year-old postmenopausal woman. She had undergone partial mastectomy and sentinel lymph node biopsy (SLNB) for her T1 left breast cancer. SLNB had indicated no lymph node metastases. The tumor was positive for hormone receptors and negative for human epidermal growth factor receptor 2. Therefore, an aromatase inhibitor and external beam irradiation had been administered as adjuvant therapy. However, the CA15-3 level was found to be elevated at 6 months postoperatively. Although imaging studies did not indicate breast cancer recurrence, CA15-3 levels continued to increase. Based on the findings of blood tests and gastroendoscopy, a diagnosis of pernicious anemia due to vitamin B12 deficiency was finally confirmed at 2 years and 6 months postoperatively. The CA15-3 level returned to normal after vitamin B12 administration. The possibility of pernicious anemia should be considered in cases of postoperative elevated CA15-3 levels with no evidence of recurrence in patients with early breast cancer.

Mucins and Cytokeratins as Serum Tumor Markers in Breast Cancer

Structural and functional characteristics of mucins and cytokeratins are shortly described. Thereafter, those commonly used in breast cancer as serum tumor markers are considered. First CA15.3, MCA, CA549, CA27.29 mucins and CYFRA21.1, TPA, TPS cytokeratins alone or in association have been examined in different stages and conditions. Then their usefulness in monitoring disease-free breast cancer patients is evaluated. The central role of the established cut-off and critical change, the "early" treatment of recurrent disease and the potential benefit in survival are other issues that have been highlighted and discussed. The successive sections and subsections deal with the monitoring of advanced disease. In them, the current recommendations and the principal findings on using the above mentioned mucins and cytokeratins have been reported. A computer program for interpreting consecutive measurements of serum tumor markers also has been illustrated. The final part of the chapter is devoted to mucins and cytokeratins as markers of circulating and disseminated tumor cells and their usefulness for prognosis.

Requests for tumor marker tests in Turkey without indications and frequency of elevation in benign conditions

AIMS

To investigate the incidence of ordering tests for tumor markers which are used in cancer diagnosis, follow-up treatment and detection of recurrence, the rate of elevation in benign diseases and which clinics order them frequently.

MATERIALS AND METHOD

Data for the tumor markers carbohydrate antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), cancer antigen 125 (CA 125), cancer antigen 15-3 (CA 15-3) and alpha- fetoprotein (AFP) that were ordered by all the clinics in our Hospital between 2010 and 2011 were screened. When excluding repeated orders the results of 3,416 patients were available. It has been determined that in which benign diseases were the tumor markers frequently ordered and which of these conditions had high levels of them.

RESULTS

CA 19-9 was ordered for 1,858 patients 191 (10.3%) were malignant while 1667 (89.7%) were ordered in benign diseases. For CEA the total was 1,710, 226 (13.2%) malignant and 1484 (86.8%) benign, and for CA 125 1267, 111 (8.8%) malignant and 1156 (91.2%) benign. AFP was ordered for 1687 cases, 80 (4.7%) malignant but 1607 (95.3%) benign. CA 15-3 was ordered 1449 times, 174 (12%) for malignant and 1275 (88%) for benign diseases. In all cases, considerable proportions were positive.

CONCLUSIONS

It was shown that clinicians frequently order tumor markers for benign conditions. The findings of this study has shown that tumor markers are used widely without indications as cancer screening tests.

Utility of serum tumor markers as an aid in the differential diagnosis of patients with clinical suspicion of cancer and in patients with cancer of unknown primary site

Cancer may be diagnosed in advanced stages, when the patient has already developed metastasis, with symptoms that can be also observed in benign diseases. The objective of this study was to evaluate tumor marker sensitivity and specificity in the differential diagnosis of patients with suspected signs of cancer. We studied 2.711 consecutive patients admitted to the Internal Medicine Department of our hospital with suspected cancer; 1.240 patients had non-malignant processes and 1.471 had malignant disease. Determinations were considered positive for suspected malignancy when serum levels were carcinoembryonic antigen >15 ng/ml (>20 in patients with renal failure or liver disease), alpha fetoprotein >40 ng/ml (>80 ng/ml in patients with liver diseases), carbohydrate antigen (CA) 19.9 > 200 U/ml (>500 U/ml in patients with liver diseases or gamma glutamyl transpeptidase (GGT) <150 UI/L or effusions; >1.000 U/ml in patients with jaundice or GGT > 150 UI/L), neuron-specific enolase >45 ng/ml (renal failure >50 ng/ml; samples with hemolysis were excluded), prostate-specific antigen > 30 ng/ml (excluding acute prostatitis), tumor-associated glycoprotein-72 >80 U/ml, cytokeratin 19 fragment 21-1 > 7.5 ng/ml (>19 ng/ml in patients with renal failure; >11 ng/ml in patients with liver cirrhosis or jaundice), >3.5 ng/ml for squamous cell carcinoma (excluding patients with renal failure or skin disorders), CA 15.3 >100 U/ml, and CA 125 >350 U/ml (>600 U/ml in patients with pleural effusion and >900 U/ml in those with ascites). There was a specificity of 97.6% in patients without malignancy, 67.4% of sensitivity in patients with malignancy, and 75.4% of sensitivity in the 1,280 patients with epithelial tumors (53.7% in patients with locally advanced tumors and 79.4% in patients with metastases). Sensitivity was 81.4% in patients with cancer of unknown primary site. Tumor markers were useful in the differential diagnosis between epithelial and non-epithelial tumors, brain masses (metastases vs. primary tumors), and between benign or malignant origin of different clinical situations such as wasting syndrome, effusions, liver or bone lesions, and effusions with a positive predictive value higher than 95%. Tumor markers are useful as an aid in the evaluation of the risk of cancer of these patients with suspected cancer and may be useful to reduce the hospitalization time, morbidity, and the number of diagnostic tests required for diagnosis.

Increased plasma concentrations of tumour markers in the absence of neoplasia

Tumour markers are a very heterogeneous group of molecules that are generally found in very small concentrations in the plasma and serum of healthy individuals. In the process of neoplastic differentiation the cell can synthesize, release, or induce synthesis of other cells, thus increasing their concentration in plasma and serum. These substances may also increase their plasma concentration in patients without cancer due to processes that increase the release or reduce catabolism, and so give rise to false positives. An understanding of the main physiopathological processes that increase the concentrations of these substances could improve our interpretation of tumour markers and their clinical application. In this study we review the physiopathological processes that may increase the plasma concentrations of tumour markers. We performed a bibliography review in PubMed, searching for causes of false positives for the following tumour markers: α-Fetoprotein, CA 125, CA 15-3, CA 19-9, CA 72-4, carcinoembryonic antigen, CYFRA 21-1, squamous cell carcinoma, prostatic specific antigen, β(2)-microglobulin, choriogonadotropin (β chain), chromogranin A, neuron specific enolase, HER2-neu, progastrin releasing peptide, S-100, and thyroglobulin. The results favour the use of tests which can identify pathological processes that may increase tumour marker concentrations.

CA 15-3: uses and limitation as a biomarker for breast cancer

CA 15-3 which detects soluble forms of MUC-1 protein is the most widely used serum marker in patients with breast cancer. Its main use is for monitoring therapy in patients with metastatic disease. In monitoring therapy in this setting, CA 15-3 should not be used alone but measured in conjunction with diagnostic imaging, clinical history and physical examination. CA 15-3 is particularly valuable for treatment monitoring in patients that have disease that cannot be evaluated using existing radiological procedures. CA 15-3 may also be used in the postoperative surveillance of asymptomatic women who have undergone surgery for invasive breast cancer. In this setting, serial determination can provide median lead-times of 5-6 months in the early detection of recurrent/metastatic breast cancer. It is unclear however, whether administering systemic therapy based on this lead-time improves patient outcome. Consequently, expert panels disagree on the utility of regularly measuring CA 15-3 in the postoperative surveillance of asymptomatic women following a diagnosis of breast cancer. The main limitation of CA 15-3 as a marker for breast cancer is that serum levels are rarely increased in patients with early or localized disease.

Do serum biomarkers really measure breast cancer?

Background

Because screening mammography for breast cancer is less effective for premenopausal women, we investigated the feasibility of a diagnostic blood test using serum proteins.

Methods

This study used a set of 98 serum proteins and chose diagnostically relevant subsets via various feature-selection techniques. Because of significant noise in the data set, we applied iterated Bayesian model averaging to account for model selection uncertainty and to improve generalization performance. We assessed generalization performance using leave-one-out cross-validation (LOOCV) and receiver operating characteristic (ROC) curve analysis.

Results

The classifiers were able to distinguish normal tissue from breast cancer with a classification performance of AUC = 0.82 ± 0.04 with the proteins MIF, MMP-9, and MPO. The classifiers distinguished normal tissue from benign lesions similarly at AUC = 0.80 ± 0.05. However, the serum proteins of benign and malignant lesions were indistinguishable (AUC = 0.55 ± 0.06). The classification tasks of normal vs. cancer and normal vs. benign selected the same top feature: MIF, which suggests that the biomarkers indicated inflammatory response rather than cancer.

Conclusion

Overall, the selected serum proteins showed moderate ability for detecting lesions. However, they are probably more indicative of secondary effects such as inflammation rather than specific for malignancy.

Evaluation of serum tumour markers concentrations in patients with homozygous β-thalassaemia in relation to demographical, clinical and biochemical parameters

Increased life expectancy in patients with homozygous beta-thalassaemia consequently increases the risk for neoplastic diseases. This study was conducted to assess the levels of five common tumour markers in thalassaemic patients and to investigate possible correlations to demographical, clinical and laboratory data. Eighty-five patients (44 female and 41 male) with homozygous beta-thalassaemia (mean age = 27.92 +/- 12.5), on regular blood transfusions and adequate chelation treatment, and 60 sex and age- matched healthy controls were enrolled in the study. Blood samples for the determination of carcinoma antigen (CA) 15.3, CA 125, CA 19.9, carcinoembryonic antigen (CEA) and alpha-fetoprotein (a-FP) were collected from every subject. Results showed that 69% of the thalassaemic patients had abnormal levels of CA 15.3, whereas only sporadic cases had increased levels of CA 125 and CA 19.9. On the contrary, all controls had normal levels of CA 15.3, CA 19.9 and CA 125. CEA and a-FP were within reference ranges both in the thalassaemic and in the control group. Levels of CA 15.3 were significantly lower in patients aged less than 20 years compared to older patients. Male patients had significantly increased levels of CA 15.3 compared to female patients. Relatively recent studies show an increased expression of CA 15.3 on progenitor cells of the erythroid lineage and increased amounts of circulating progenitor cells even in well-transfused thalassaemic patients. However, it seems that there are also other factors contributing to this phenomenon. In conclusion, our results indicate that CA 15.3 seems to be an unreliable marker of occult malignancy in patients with beta-thalassaemia. However, more studies are needed to support these preliminary results.

Serum tumor markers in breast cancer: are they of clinical value?

BACKGROUND

Although multiple serum-based tumor markers have been described for breast cancer, such as CA 15-3, BR 27.29 (CA27.29), carcinoembryonic antigen (CEA), tissue polypeptide antigen, tissue polypeptide specific antigen, and HER-2 (the extracellular domain), the most widely used are CA 15-3 and CEA.

METHODS

The literature relevant to serum tumor markers in breast cancer was reviewed. Particular attention was given to systematic reviews, prospective randomized trials, and guidelines issued by expert panels.

RESULTS

Because of a lack of sensitivity for early disease and lack of specificity, none of the available markers is of value for the detection of early breast cancer. High preoperative concentrations of CA 15-3 are, however, associated with adverse patient outcome. Although serial determinations of tumor markers after primary treatment for breast cancer can preclinically detect recurrent/metastatic disease with lead times of approximately 2-9 months, the clinical value of this lead time remains to be determined. Serum markers, however, are the only validated approach for monitoring treatment in patients with advanced disease that cannot be evaluated by use of conventional criteria.

CONCLUSIONS

CA 15-3 is one of the first circulating prognostic factors for breast cancer. Preoperative concentrations thus might be combined with existing prognostic factors for predicting outcome in patients with newly diagnosed breast cancer. At present, the most important clinical application of CA 15-3 is in monitoring therapy in patients with advanced breast cancer that is not assessable by existing clinical or radiologic procedures.