Tumor-associated antigen TA90 immune complex assay predicts recurrence and survival after surgical treatment of stage I-III melanoma

Melanoma's New Frontier: Exploring the Latest Advances in Blood-Based Biomarkers for Melanoma

Melanoma is one of the most malignant cancers, and the global incidence of cutaneous melanoma is increasing. While melanomas are highly prone to metastasize if diagnosed late, early detection and treatment significantly reduce the risk of mortality. Identifying patients at higher risk of metastasis, who might benefit from early adjuvant therapies, is particularly important, especially with the advent of new melanoma treatments. Therefore, there is a pressing need to develop additional prognostic biomarkers for melanoma to improve early stratification of patients and accurately identify high-risk subgroups, ultimately enabling more effective personalized treatments. Recent advances in melanoma therapy, including targeted treatments and immunotherapy, have underscored the importance of biomarkers in determining prognosis and predicting treatment response. The clinical application of these markers holds the potential for significant advancements in melanoma management. Various tumor-derived genetic, proteomic, and cellular components are continuously released into the bloodstream of cancer patients. These molecules, including circulating tumor DNA and RNA, proteins, tumor cells, and immune cells, are emerging as practical and precise liquid biomarkers for cancer. In the current era of effective molecular-targeted therapies and immunotherapies, there is an urgent need to integrate these circulating biomarkers into clinical practice to facilitate personalized treatment. This review highlights recent discoveries in circulating melanoma biomarkers, explores the challenges and potentials of emerging technologies for liquid biomarker discovery, and discusses future directions in melanoma biomarker research.

Cabozantinib for the treatment of hepatocellular carcinoma

Introduction: The randomized, placebo-controlled, phase III CELESTIAL trial demonstrated statistically and clinically significant improvement in overall survival with cabozantinib in patients with advanced hepatocellular carcinoma (HCC) previously treated with sorafenib. Most frequently reported adverse events included palmar-plantar erythrodysesthesia, hypertension, increased aspartate aminotransferase, fatigue, and diarrhea. Areas covered: In this review we analyze and discuss preclinical and clinical data of cabozantinib. We summarize efficacy and safety results of phase II and III trials of cabozantinib in the treatment of patients with advanced HCC and we present ongoing trials of cabozantinib in combination with checkpoint inhibitors. Expert opinion: Cabozantinib is a new second-line and the only third-line treatment for patients with advanced HCC, nevertheless some data are still missing to better inform clinical decisions on how to treat specific patient populations. Next trials designs will have to incorporate heavy efforts in terms of translational research to maximize the benefits of such treatments.

Cabozantinib in patients with hepatocellular carcinoma failing previous treatment with sorafenib

Over the past 10 years, sorafenib has been the only systemic agent approved for the treatment of patients with unresectable hepatocellular carcinoma. Recently, lenvatinib was demonstrated noninferior to sorafenib, and regorafenib and ramucirumab were demonstrated superior to placebo in patients progressing on sorafenib and in patients with elevated α-fetoprotein-failing sorafenib, respectively. Phase I–II trials of immune checkpoint inhibitors reported promising efficacy signals. Recently, the randomized, placebo-controlled, Phase III CELESTIAL trial demonstrated statistically and clinically significant increase in overall survival from 8 months with placebo to 10.2 months with cabozantinib in patients failing sorafenib. Furthermore, the study showed a significant improvement in all the efficacy end points. Main adverse events were palmar–plantar erythrodysesthesia, hypertension, increased aspartate aminotransferase, fatigue and diarrhea.

The roles and applications of autoantibodies in progression, diagnosis, treatment and prognosis of human malignant tumours

The existence of autoantibodies towards an individual's own proteins or nucleic acids has been established for more than 100years, and for a long period, these autoantibodies have been believed to be closely associated with autoimmune diseases. However, in recent years, researchers have become more interested in the role and application of autoantibodies in progression, diagnosis, treatment and prognosis of human malignant tumours. Over the past few decades, numerous epidemiological studies have shown that the risk of certain cancers is significantly altered (increased or decreased) in patients with autoimmune diseases, which suggests that autoantibodies may play either promoting or suppressing roles in cancer progression. The idea that autoantibodies are directly involved in tumour progression gains special support by the findings that some antibodies secreted by a variety of cancer cells can promote their proliferation and metastasis. Because the cancer cells generate cell antigenic changes (neoantigens), which trigger the immune system to produce autoantibodies, serum autoantibodies against tumour-associated antigens have been established as a novel type of cancer biomarkers and have been extensively studied in different types of cancer. The autoantibodies as biomarkers in cancer diagnosis are not only more sensitive and specific than antigens, but also could appear before clinical evidences of the tumours, thus disclosing them. The observations that cancer risk is lower in patients with some autoimmune diseases suggest that certain autoantibodies may be protective from certain cancers. Moreover, the presence of autoantibodies in healthy individuals implies that it could be safe to employ autoantibodies to treat cancer. Of note, an autoantibodies derived from lupus murine model received much attention due to their selective cytotoxicity for malignant tumour cell without harming normal ones. These studies showed the therapeutic value of autoantibodies in cancer. In this review, we revisited the pathological or protective role of autoantibodies in cancer progression, summarize the application of autoantibodies in cancer diagnosis and prognosis, and discuss the value of autoantibodies in cancer therapy. The studies established to date suggest that autoantibodies not only regulate cancer progression but also promise to be valuable instruments in oncological diagnosis and therapy.

Biomarkers in melanoma: Stage III and IV disease

The prognosis associated with Stage III melanoma is variable (17-65% 5-year survival) and primarily influenced by the number of lymph nodes involved, the presence of ulceration in a primary lesion, and the tumor burden present in each lymph node. In patients with metastatic (Stage IV) melanoma, the prognosis remains dismal (6-18% 5-year survival) and is influenced primarily by the sites (and extent) of metastatic involvement. Serum lactate dehydrogenase is the only prognostic biomarker useful in metastatic melanoma and it has been incorporated into the 2002 American Joint Committee on Cancer tumor, node, metastasis staging system. In this review, the known prognostic factors in Stage III and IV melanoma are reviewed. Selected investigational therapies and associated biomarkers are also discussed.

Detection of melanoma-derived cancer-testis antigen CT16 in patient sera by a novel immunoassay

Cancer-testis antigens (CTAs) are expressed mainly in various cancer tissues and in testis or placenta. Because of their restricted expression pattern, the CTAs can be potentially used for vaccine development and diagnostic applications. CTA CT16 has been found to be expressed in lung and renal cancers as well as in melanomas. Detection of CT16 protein directly from patient serum could facilitate monitoring of tumor growth and response to therapy in CT16-positive patients. A highly sensitive time-resolved fluorescence-based immunoassay measuring CTA CT16 in serum was developed. Generally, CTAs have not been measured directly from body fluids. CT16 level was detectable in 14 of 23 (61%) patients with metastatic melanoma, whereas none of the nine healthy volunteers collected by us had measurable CT16 level. For an unknown reason, 1 of 20 commercial control serum samples gave a positive result. The Wilcoxon-Mann-Whitney exact test showed statistically significant difference when patients with metastatic melanoma were compared to our control group (p = 0.006) or to the commercial set (p < 0.001). Four melanoma patients had exceptionally high serum CT16 level. CT16 did not correlate either with S100B, a recognized marker of progressing melanoma, or with unspecific serum marker lactate dehydrogenase. Elevation of CT16 titers preceded or followed the clinical diagnosis of disease progression in four patients with metastatic melanoma. As a conclusion, our results show that CT16 protein can be measured directly from patient serum, and the developed assay has a potential for clinical use.

Old and new serological biomarkers in melanoma: where we are in 2009

Biomarkers play an important role in the diagnosis and prognostic classification of various cancers and can be useful in monitoring the patient's clinical course of disease and response to therapy. Generally, biomarkers are proteins and their expressions are associated with malignant disease. In the majority of cases, the marker molecules are expressed by the tumour cells themselves or by the tumour microenvironment cells. Thus, most biomarkers can primarily be found in malignant tissues, but after active secretion or passive release at tumour destruction, they become detectable in body fluids such as blood. Besides morphological and histopathological biomarkers (anatomic site, type of the primary tumour, tumour size, invasion depth, vascular invasion and ulceration), an increasing variety of serological markers have been identified, providing the possibility of a more detailed diagnostic and prognostic subgrouping of tumour entities, up to and even changing existing classification systems. The goal of this review is to provide an overview of old and more recent serological biomarkers in malignant melanoma. We will first focus on confirmed and nonconfirmed serum tumour markers, followed by proteomic profiling, an innovative approach to identify new and better serological biomarkers in melanoma, and ending with the predictive factors for treatments in this pathology.

Biomarkers of metastatic melanoma

Melanoma, one of the most aggressive forms of human cancer, has undergone an alarming increase in incidence in recent years. Early detection is a prerequisite for proper diagnosis and therapy orientation. Soluble biomarkers are an important tool for early diagnosis. Markers that are associated with melanocyte functions imply the enzymes involved in melanin synthesis and the melanin-related metabolites. Proteins such as autocrine melanocyte cell growth factor and melanoma metastasis suppressor have gained attention in the biomarkers domain. The antimelanoma immune response elicited in patients can not only provide new biomarkers but important therapeutic approaches in specific treatments. All the molecules generated during the metastasis process, invasion of neighboring tissue, angiogenesis, invading lymphatic/blood vessels and establishing new tumors at a distant site, are targets for biomarker discovery.

Melanoma biomarkers: Vox clamantis in deserto (Review)

Detecting malignant melanoma at an early stage, monitoring therapy, predicting recurrence and identifying patients at risk for metastasis continue to be a challenging and demanding objective. The last two decades have witnessed innovations in the field of melanoma biomarkers. However, global agreement concerning monitoring and early detection has yet to be reached. This is a review of the current literature regarding melanoma biomarkers including demographic, clinical, pathological and molecular biomarkers that are produced by melanoma or non-melanoma cells. A number of these biomarkers demonstrate promising results as possible methods for early detection, predicting recurrence and monitoring therapy. Other biomarkers appear to be promising for identifying patients at risk for metastasis. We reviewed the most pertinent information in the field thus far and how this knowledge can impact, or not, the management of melanoma patients prognostically and therapeutically.

Preoperative serum TA90-IC as an adjunct to serum CA 19-9 in the diagnosis of pancreatic malignancy: a pilot study

PURPOSE

Because TA90, a 90-kDa immunogenic tumor-associated antigen, is expressed by pancreatic cancer cells, we hypothesized that the serum level of its immune complex with IgG (TA90-IC) might be a useful marker for diagnosis of pancreatic malignancy. We also wanted to compare TA90-IC with CA 19-9 in the diagnosis of pancreatic cancer.

METHODS

We undertook a retrospective study of prospectively collected sera from patients with histopathologically proven pancreatic malignancies. Patient sera were analyzed for TA90-IC and CA 19-9. Sera of sex-matched and age-matched healthy volunteers (controls) were analyzed for TA90-IC. The study was conducted at a tertiary medical center. Twenty-one patients with pancreatic malignancies and 29 controls, from whom sera had been obtained and cryopreserved, were included. A positive TA90-IC level was defined as an optical density >/= 0.410 at 405 nm following an enzyme-linked immunosorbent assay based on a murine monoclonal antibody. CA 19-9 levels were determined by immunoradiometric assay performed at outside laboratories (normal range, 0 to 37 U/mL).

RESULTS

Of the 21 patients, 14 had positive TA90-IC levels and 18 had increased CA 19-9 levels (67% vs 86%; p = 0.157). The TA90-IC levels were significantly higher in the cancer group than in the control group (p = 0.0003). Of the 3 patients with normal CA 19-9 levels, 2 had positive TA90-IC levels. The combination of both markers identified 95% of patients with pancreatic malignancy, a significantly higher diagnostic rate than that of either marker alone (p = 0.014). TA90-IC sensitivity was higher for stage II and III disease than for stage IV disease (82% vs 50%).

CONCLUSIONS

TA90-IC assay may improve the prediction of pancreatic malignancy when used in combination with CA 19-9 levels. Because TA90-IC appears to have improved diagnostic accuracy with smaller tumor burden, the role of TA90-IC as an adjunct to CA 19-9 in screening and monitoring progression of early disease warrants further investigation.

Targeting serum antibody for cancer diagnosis: a focus on colorectal cancer

The ability of the immune system to magnify the appearance of disease by generating relatively large amounts of antibody in response to small amounts of disease makes it a natural biosensor, and serum antibodies have emerged as promising biomarkers for the detection of cancer. This review summarizes recent progress in targeting serum antibodies for cancer diagnosis, with a particular focus on colorectal cancer (CRC). Several serum antibodies have been detected at increased levels in CRC patients, including p53, carcinoembryonic antigen, Ras, topoisomerase II-alpha, histone deacetylase 3 and 5, ubiquitin C-terminal hydrolase L3, tropomyosin and cyclin B1. As each antibody is only present in a limited proportion of patients (usually < 40%), a combination of serum antibodies that defines the 'immunological signature' of cancer needs to be developed. High-throughput methods to identify new serum antibodies for cancer diagnosis are also reviewed.

Molecular diagnostics in melanoma

Molecular pathology is rapidly evolving, featuring continuous technologic improvements that offer novel clinical opportunities for the recognition of disease predisposition, for identifying sub-clinical disease, for more accurate diagnosis, for selecting efficacious and non-toxic therapy, and for monitoring of disease outcome. Currently, the identification and prognosis of primary cutaneous melanoma is based on histologic factors (tumor depth and ulceration) and clinical factors (number of lymph node and/or distant metastases). However, metastasis can occur in patients with thin melanomas, and sentinel lymph node biopsy does not identify all patients at risk for distant metastasis. New markers exist that correlate with melanoma progression, which may aid in melanoma identification, prognostication, and detection of minimal residual disease/early recurrence. Moreover, not many therapeutic options exist for melanoma as no regimen prolongs survival. Emerging data with investigational therapies suggest that certain markers might play a crucial role in identifying patients who will respond to therapy or show utility in the monitoring the response to therapy. Herein, molecular diagnostics that can potentially benefit the individual melanoma patient will be discussed.

Serum YKL-40 Predicts Relapse-Free and Overall Survival in Patients With American Joint Committee on Cancer Stage I and II Melanoma

Purpose

To evaluate the novel tumor biomarker YKL-40 in serial serum samples from patients with American Joint Committee on Cancer (AJCC) stage I and II melanoma from the time of diagnosis and during routine follow-up. Macrophages, neutrophils, and cancer cells secrete YKL-40, and a high serum level has been associated with poor prognosis in patients with several cancer types.

Patients and Methods

Serum samples from 234 patients with stage I (n = 162) and II (n = 72) melanoma were analyzed for YKL-40 by enzyme-linked immunosorbent assay. Serial samples were obtained before definitive primary surgery and during follow-up.

Results

After a median follow-up period of 66 months (range, 1 to 97 months), 41 relapses (18%) and 39 deaths (17%) were observed. Serum YKL-40 treated as an updated continuous covariate were analyzed together with the covariates sex, age, primary tumor site, ulceration, thickness, Clark level and histologic subtype in a Cox proportional hazard model. Serum YKL-40 was an independent prognostic factor of relapse-free survival (hazard ratio [HR], 1.6; 95% CI, 1.1 to 2.5; P = .03) and overall survival (HR, 1.8; 95% CI, 1.2 to 2.6; P = .002) together with thickness and ulceration. The serum level of YKL-40 (dichotomized as normal or elevated) at the time of diagnosis was also an independent prognostic factor for overall survival (HR, 3.6, 95% CI, 1.7 to 7.7; P = .001).

Conclusion

Serum YKL-40 may be an early biomarker of relapse and survival in patients with AJCC stage I and II melanoma. Serum YKL-40 may also be useful for patient stratification and follow-up in clinical trials. Our results need confirmation in an independent study.

The sentinel within: exploiting the immune system for cancer biomarkers

The release of proteins from tumors triggers an immune response in cancer patients. These tumor antigens arise from several mechanisms including tumor-specific alterations in protein expression, mutation, folding, degradation, or intracellular localization. Responses to most tumor antigens are rarely observed in healthy individuals, making the response itself a biomarker that betrays the presence of underlying cancer. Antibody immune responses show promise as clinical biomarkers because antibodies have long half-lives in serum, are easy to measure, and are stable in blood samples. However, our understanding of the specificity and the impact of the immune response in early stages of cancer is limited. The immune response to cancer, whether endogenous or driven by vaccines, involves highly specific T lymphocytes (which target tumor-derived peptides bound to self-MHC proteins) and B lymphocytes (which generate antibodies to tumor-derived proteins). T cell target antigens have been identified either by expression cloning from tumor cDNA libraries, or by prediction based on patterns of antigen expression ("reverse immunology"). B cell targets have been similarly identified using the antibodies in patient sera to screen cDNA libraries derived from tumor cell lines. This review focuses on the application of recent advances in proteomics for the identification of tumor antigens. These advances are opening the door for targeted vaccine development, and for using immune response signatures as biomarkers for cancer diagnosis and monitoring.

Tumor cell and circulating markers in melanoma: Diagnosis, prognosis, and management

The search is on for biomarkers for use in the diagnosis, staging, prognosis, and management of patients with melanoma. As with many types of cancer, the hematogenous spread of melanoma is a bad prognostic sign, and many groups have attempted to detect circulating melanoma cells in patients with different stages of melanoma. Some studies have used direct extraction of intact tumor cells from the peripheral blood and others the detection of surrogate markers of circulating melanoma cells, such as tyrosinase or MART-1. However, a correlation between the detection of intact melanoma cells in the circulation and prognosis is controversial. Many other biomarkers have also been studied, including lactate dehydrogenase, S100, TA90, and C-reactive protein. Much progress has been made, and preliminary studies have shown promise with many of these markers. Finally, the detection of tumor-specific circulating DNA has shown promise as a prognostic and diagnostic marker of disease in melanoma as well. In this review we examine the most promising biomarkers for use in patients with cutaneous melanoma.

Melanoma

The surgical management of melanoma continues to evolve. A large body of information serves as a foundation for the oncologic principles, surgical excisions, and reconstructive methodologies that are currently in use. This article serves as a guide for the physician considering surgical management of the melanoma patient.

Endogenous immune response to early- and intermediate-stage melanoma is correlated with outcomes and is independent of locoregional relapse and standard prognostic factors

BACKGROUND

Standard prognostic factors, including precise staging of the regional lymph nodes, cannot accurately determine which early-stage melanomas will metastasize. The immune response to a 90-kd tumor-associated antigen correlates with occult nodal disease and survival of patients receiving vaccine therapy for melanoma. We hypothesized that this response might have prognostic significance independent of standard prognostic features.

STUDY DESIGN

Patients with primary melanomas 1.01 to 2.00 mm and tumor-negative regional lymph nodes were identified. Group 1 comprised 50 patients who died of metastases within 7 years after complete surgical treatment; group 2 comprised 50 patients who were matched with group 1 for six standard prognostic features but who lived at least 10 years without recurrence. Postoperative sera were analyzed for an immune complex to TA90 and for immunoglobulin-G and immunoglobulin-M antibodies against TA90.

RESULTS

Median thickness of the primary melanoma was 1.40 +/- 0.31 mm and 1.42 +/- 0.32 mm in groups 1 and 2, respectively; median Clark's level of invasion was III in both groups, and 26 patients in each group had ulcerated primaries. Median TA90-IC level and rate of TA90-IC positivity (optical density greater than 0.410) were 0.557 +/- 0.43 and 82%, respectively, in group 1 and 0.305 +/- 0.15 and 18%, respectively, in group 2 (p < 0.001). The anti-TA90 IgM level was significantly elevated in 12% of group 1 (median titer 1:150) and 62% of group 2 (median titer 1:800) (p < 0.001). There was no significant difference in anti-TA90 IgG levels between the two groups.

CONCLUSIONS

A positive TA90-IC level and absence of an anti-TA90 IgM response correlate with distant metastasis when melanoma is low risk or intermediate risk by standard prognostic factors.

New diagnostic techniques in staging in the surgical treatment of cutaneous malignant melanoma

The emphasis of the research on the surgical treatment of melanoma has been on the resection margins, the role of elective lymph node dissection in high risk patients and the value of adjuvant regional treatment with hyperthermic isolated lymph perfusion with melphalan. Parallel to this research, new diagnostic techniques, such as Positron Emission Tomography and the introduction of the sentinel lymph node biopsy with advanced laboratory methods such as immuno-histochemical markers, and reverse transcriptase polymerase chain reaction, have been developed to facilitate early detection of metastatic melanoma. The role of these new techniques on the staging and surgical treatment of melanoma is discussed in this paper.

Enhanced humoral immune response correlates with improved disease-free and overall survival in American Joint Committee on Cancer stage II melanoma patients receiving adjuvant polyvalent vaccine

PURPOSE

Although the improved overall survival (OS) of patients who receive Canvaxin (CancerVax Corp, Carlsbad, CA) polyvalent vaccine (PV) immunotherapy for metastatic melanoma has been correlated with cellular and humoral immune responses, the mechanisms of vaccine immunotherapy for early-stage melanoma are unclear. Specific immune responses to tumor-associated antigens might correlate with disease-free survival (DFS) and OS in patients receiving adjuvant PV therapy for primary melanoma.

PATIENTS AND METHODS

Eighty-three patients received PV plus bacille Calmette-Guérin after wide excision of American Joint Committee on Cancer stage II melanoma. Humoral and cellular responses during the first 12 weeks of adjuvant immunotherapy were assessed by serum antibody titers to a tumor-associated 90-kd glycoprotein antigen (TA90) expressed by PV, and by delayed-type hypersensitivity (DTH) skin testing with PV (PV-DTH).

RESULTS

At a median follow-up period of 46.6 months (range, 10.7 to 93.6 months), an increased PV-DTH response seemed to be associated with improved 5-year DFS (54% v 20%) and 5-year OS (75% v 60%), but the correlations were not statistically significant. Anti-TA90 immunoglobulin (Ig) M levels > or = 1:800 were significantly correlated with improved 5-year DFS and improved 5-year OS, and multivariate analysis identified anti-TA90 IgM as an independent prognostic factor for OS and DFS.

CONCLUSION

These findings suggest that an increased IgM response in patients receiving PV therapy for stage II melanoma is associated with decreased recurrence and improved survival.

Serum TA90 immune complex assay can predict outcome after resection of thick (> or =4 mm) primary melanoma and sentinel lymphadenectomy

BACKGROUND

We hypothesized that the postoperative serum level of TA90-IC, an immune complex of a 90-kDa tumor-associated antigen and its antibody, might have a significant correlation with recurrence and survival in patients with thick primary melanomas.

METHODS

We used our prospective melanoma database to identify all patients who underwent wide local excision and sentinel lymphadenectomy for primary melanomas > or =4 mm and from whom sera had been collected and cryopreserved within 6 months after surgery. These sera were analyzed in a blinded fashion for TA90-IC status by using our double-determinant enzyme-linked immunosorbent assay. Results were correlated with disease-free survival (DFS) and overall survival (OS). Standard prognostic factors for melanoma were then compared with TA90-IC status for the prediction of DFS and OS.

RESULTS

The sensitivity and specificity of the TA90-IC assay for predicting recurrence were 70% and 85%, respectively. Five-year DFS and OS rates were higher for the TA90-IC-negative group than the positive group. The differences in DFS and OS between the TA90-IC-negative and -positive groups were significant. At a median follow-up of 25 months, multivariate analysis identified postoperative TA90-IC status and sex as significant predictors of DFS. TA90-IC status was the only independent prognostic factor with multivariate analysis.

CONCLUSIONS

TA90-IC status after resection of thick primary melanoma accurately predicts outcome. A positive postoperative TA90-IC level might affect a decision regarding adjuvant therapy, regardless of regional nodal status.

Serum total gangliosides and TA90-IC levels: novel immunologic markers in colorectal cancer

BACKGROUND

Because of the challenge in defining prognostic markers predictive of recurrence or progression, carcinoembryonic antigen (CEA) remains the most frequently used marker in colorectal cancer, despite its low sensitivity. We hypothesized that TA90-IC status and serum ganglioside levels might be useful markers and might be of prognostic significance in colorectal cancer.

METHODS

Serum samples from 68 patients undergoing surgical treatment for histologically proven colorectal cancer were analyzed for the presence of CEA, serum gangliosides, and TA90-IC. Forty-one patients had node-negative disease, whereas 27 patients had limited metastatic disease. The intent was curative resection, even for patients with metastatic disease. Cryopreserved serum specimens were analyzed in a blinded fashion for total serum ganglioside levels (by an assay that detects lipid-associated sialic acids), for CEA, and for TA90-IC (by a murine monoclonal antibody-based enzyme-linked immunosorbent assay). A positive value for TA90-IC levels was defined as an optical density (OD) of more than 0.410 at 405 nm.

RESULTS

Serum ganglioside levels were elevated more frequently than CEA concentrations (84% vs 44%). The combination of serum ganglioside and CEA values was more sensitive (88%) than CEA value alone (44%) in identifying patients with early-stage colorectal cancer. TA90-IC levels were elevated more frequently than CEA concentrations (56% vs 32%). The combination of TA90-IC and CEA values was more sensitive (72%) than CEA value alone (32%) in identifying patients with advanced-stage colorectal cancer. At an enzyme-linked immunosorbent assay cutoff level of 0.410, 15 (56%) patients had positive TA90-IC values. Fourteen patients alive with residual disease had a median OD TA90-IC level of 0.879, and only three patients had levels below the OD cutoff value of 0.410. Thirteen patients with no evidence of disease had a median level of 0.277, and only four patients had OD levels > or = 0.410. TA90-IC was significantly higher in the alive with residual disease patients than those rendered no evidence of disease (P = 0.02).

CONCLUSIONS

We speculate that a multiple-marker analysis that combines CEA values with serum ganglioside and TA90-IC values may be more sensitive than CEA value alone for detecting colorectal cancer. The potential prognostic significance of TA90-IC status in advanced disease warrants further investigation.