Squamous Cell Carcinoma Antigen and Protein-Bound Sialic Acid in the Management of Head and Neck Cancer

Total Sialic Acid as a Tumor Marker for Oral Cancer

Serum sialic acid levels were measured in 80 healthy subjects, in 60 patiens with benign tumors and in 110 patients with oral cancer. It was shown that these levels were significantly elevated in oral cancer patients compared to healthy controls and patients with benign tumors (p < 0.01); they were higher in patients with stage III and stage IV disease than in those with stage I and II disease (p < 0.01). However, no difference was observed between healthy controls and stage I and II cancer patients. The results of this study suggest that the determination of sialic acid levels may be of value in the diagnosis of oral cancer, but its usefulness as an adjunct in clinical staging is limited.

Serum total sialic acid in cholangiocarcinoma patients: an ROC curve analysis

OBJECTIVES

This study was undertaken to establish the diagnostic utility of serum total sialic acid (TSA) for patients with cholangiocarcinoma (CCA).

DESIGN AND METHODS

Serum TSA was determined in 89 histologically confirmed CCA patients, 38 with benign hepatobiliary diseases (BHD) and 43 healthy persons. To check whether the test could adequately discriminate between these groups, complete statistical Receiver Operating Characteristic (ROC) curves were analyzed.

RESULTS

The mean value of serum TSA in CCA patients (2.75 +/- 0.67 mmol/L) was significantly higher than that in the BHD (2.33 +/- 0.69 mmol/L p < 0.002) and healthy persons (1.89 +/- 0.46 mmol/L p < 0.001) groups. The areas under the ROC curves were 0.6699 and 0.8558, respectively. A cut-off value of 2.33 mmol/L discriminated between the CCA, BHD and healthy groups with a sensitivity of 71.9% and a positive predictive value range of 80 to 89%.

CONCLUSION

Determination of TSA yielded high diagnostic values for differentiating between CCA, BHD and healthy persons. The determination of serum TSA would be most useful as an adjunct diagnosis rather than an early detection and screening tool because of the apparent nonspecificity of SA to a given disease.

Prolactin as a local growth promoter in patients with locally advanced tongue cancer: GCRI experience

BACKGROUND

The purpose of this study was to assess the role of prolactin (PRL) in men with locally advanced tongue cancer.

METHODS

Circulating PRL was assayed immunoradiometrically in pretherapeutic and sequential blood samples of 99 patients with locally advanced tongue cancer. Patients were followed for 3 years or until their death within a stipulated time. Immunohistochemical localization of PRL was performed on formalin-fixed paraffin-embedded tissue sections. Tumoral prolactin receptors (PRLR) were estimated by ligand binding assay; the expression of PRL mRNA and PRLR mRNA were carried out by reverse transcriptase polymerase chain reaction (RT-PCR). Furthermore, PRL amplimer was sequenced and compared with human pituitary PRL amplimer.

RESULTS

Pretherapeutic PRL levels were significantly higher in patients with locally advanced tongue cancer compared with controls (p =.01). Thirty-four percent (34 of 99) of the patients had hyperprolactinemia (PRL >/=15.0 ng/mL). Univariate survival analysis showed that patients with pretherapeutic hyperprolactinemia had a significantly shorter overall survival than patients with pretherapeutic PRL <15.0 ng/mL serum (p =.0009). In multivariate analysis, PRL emerged as the most significant independent prognostic factor influencing overall survival. Furthermore, changes in serial PRL levels showed excellent correlation with response to therapy and progression of disease. Forty-four percent (24 of 54) of the tumors showed positive immunoreactivity with PRL antibody, indicating that PRL or a molecule similar to it is produced by tongue tumors. PRL mRNA expression was seen in 85% (43 of 50) of the tumors and confirmed the de novo synthesis of PRL. Sequence analysis of the 234 bp PRL amplimer revealed that the sequence was homologous to exon 5 of pituitary PRL mRNA. The action of PRL is mediated by PRLR, and it was observed that the PRLR positivity by ligand binding assay was 33%. The expression of PRLR mRNA by RT-PCR showed two forms of PRLR mRNA (ie, intermediate form [500-600 bp] seen in 82% (41 of 50 ) of the tumors and the long form [800-900 bp] seen in 36% (18 of 50) of the tumors. In 82% (41 of 50) of the tumors, either the intermediate or long form was seen.

CONCLUSIONS

This multifaceted study of PRL suggests that tongue cancer cells produce PRL, and this ectopically produced PRL might be acting as a major local growth promoter by means of autocrine and paracrine mechanisms. Looking at its prognostic value and correlation with disease activity, it may provide new insights into treatment of tongue cancer.

Squamous cell carcinoma antigen in patients with cancer of the larynx

The purpose of this study was to evaluate the clinical usefulness of squamous cell carcinoma antigen (SCC Ag) in patients with squamous cell carcinoma of the larynx. Plasma specimens were obtained from 70 patients with cancer of the larynx before and after treatment and during follow-up. Disease status and the marker levels were determined blind to each other. Microparticle enzyme immunoassay (IMx SCC) was used to measure the SCC Ag level. Applying standard normal limits the sensitivity of the marker at diagnosis was 25.7%. SCC Ag levels were generally lower after therapy than before. Relapse occurred more often in patients with an abnormal pretreatment SCC Ag level, which was more frequent in those with nodal invasion. The marker level increased in 70% of the patients with relapse before the clinical detection of recurrence. SCC Ag is of limited usefulness in the primary diagnosis of cancer of the larynx, but is useful in detecting recurrence of cancer.

Occurrence of sialic acids in healthy humans and different disorders

Sialic acid (SA), N-acetylated derivatives of neuraminic acid, play a central role in the biomedical functioning of humans. The normal range of total sialic acid (TSA) level in serum/plasma is 1.58-2.22 mmol L-1, the free form of SA only constituting 0.5-3 mumol L-1 and the lipid-associated (LSA) forms 10-50 mumol L-1. Notably, considerably higher amounts of free SA are found in urine than in serum/plasma (approximately 50% of the total SA). In inherited SA storage diseases such as Salla's disease, SA levels are elevated many times over, and their determination during clinical investigation is well established. Furthermore, a number of reports describe elevated SA levels in various other diseases, tentatively suggesting broader clinical utility for SA markers. Increased SA concentrations have been reported during inflammatory processes, probably resulting from increased levels of richly sialylated acute-phase glycoproteins. A connection between increased SA levels and elevated stroke and cardiovascular mortality risk has also been reported. In addition, SA levels are slightly increased in cancer, positively correlating with the degree of metastasis, as well as in alcohol abuse, diabetes, chronic renal failure and chronic glomerulonephritis. Several different mechanisms are assumed to underlie the elevated SA concentrations in these disorders. The apparent non-specificity of SA to a given disease limits the potential clinical usefulness of SA determination. In addition, some non-pathological factors, such as aging, pregnancy and smoking, may cause changes in SA concentrations. The absolute increases in SA levels are also rather small (save those in inherited SA storage disorders); this further limits the clinical potential of SA as a marker. Tentatively, SA markers might serve as adjuncts, when combined with other markers, in disease screening, disease progression follow-up, and in the monitoring of treatment response. To become clinically useful, however, the existing SA determination assays need to be considerably refined to reduce interferences, to be specific for certain SA forms, and to be more easy to use.

Prolactin: its role in advanced tongue cancer

Serum prolactin was measured pretherapeutically and sequentially thereafter using immunoradiometric assay method in 37 male patients with advanced tongue cancer and compared with 23 healthy, age-matched controls. Prolactin levels were correlated with age, various clinicopathologic parameters, overall survival, and patients with response and those with progressive disease. Patients with advanced tongue cancer had higher prolactin levels than controls (P < 0.02), but intergroup variation in prolactin was not observed when considering the age, site of the lesion, disease stage, histologic grade, and keratin. Of the patients, 30% had hyperprolactinemia (prolactin > 15.0 ng/ml). To assess the prognostic significance of pretherapeutic prolactin level, the patients were divided according to the cutoff level of prolactin (15.0 ng/ml). Hyperprolactinemic patients had more unfavourable prognosis than patients with prolactin < 15.0 ng/ml (X2 = 2.91, df = 1, P < 0.0037). In monitoring disease course, patients who responded to treatments had decreased prolactin levels at the end of 18 months as compared to their pretherapeutic levels (P < 0.01). In patients who subsequently developed progressive disease within 18 months, prolactin levels reduced initially at response, whereas with disease progression, prolactin levels increased significantly (P < 0.05). The positive and negative predictive value of prolactin was 100%. Immunohistochemical localization confirmed the ectopic production of prolactin by tongue tumors. In conclusion, our data indicate that hyperprolactinemia may be an independent predictor of short-term prognosis; circulating prolactin may be used as a marker for monitoring disease course in patients with advanced tongue cancer, and prolactin is produced ectopically by tongue tumors.

Circulating markers in squamous cell carcinoma of the head and neck: a review

Biological markers of disease enhance the ability to diagnose, treat and evaluate results of therapy and are especially intriguing for their potential use in the management of malignant tumours. The serum levels of various biochemical substances have been shown to be abnormal for many cancers and are utilised in the management of affected patients. Several markers have been thoroughly investigated for potential clinical utility in head and neck carcinoma. Although no single marker has been found to be adequately sensitive and specific, combinations of markers may improve the utility for some aspects of patient management. This review highlights the literature to date in the realm of circulating markers for head and neck carcinoma. A discussion of the potential usefulness and limitations of such markers follows.