SciELO - Scientific Electronic Library Online

vol.96 número4Colelitiasis no complicada asociada con ERGE: Resultados de la cirugía laparoscópica combinada en pacientes con bajo riesgo quirúrgicoUtilidad del gliceril trinitrato en el tratamiento tópico de la fisura anal índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados




Links relacionados


Revista Española de Enfermedades Digestivas

versión impresa ISSN 1130-0108

Rev. esp. enferm. dig. vol.96 no.4 Madrid abr. 2004



Tissue CA-19.9 content in colorectal adenomas and its value in the assesment of dysplasia

I. Salces, I. Vegh2, S. Rodríguez-Muñoz, F. Colina1, A. Pérez1, S. Soto, F. Sánchez, J. de la Cruz3 and J. A. Solís-Herruzo

Departments of Digestive Diseases, 1Pathology, 2Unit of Research: Research Center and 3Clinical Epidemiology Unit.
Hospital 12 de Octubre. Universidad Complutense. Madrid, Spain



Background: occasionally, the risk of malignant transformation may be difficult to establish in adenomatous polyps due to the fact that they contain areas with variable grades of dysplasia. A measurement of tissue tumor markers may be useful to recognize these adenomas.
Objectives: the aims of this study were: to establish firstly the relationship between carbohydrate antigen 19.9 (CA-19.9) content in the colorectal mucosa and the characteristics of polyps, and secondly, the diagnostic value of the former's measurement.
Patients and methods: tissue CA-19.9 concentration was measured in 155 colorectal samples obtained from 145 patients (21 normal mucosa; 113 adenomatous polyps; 21 adenocarcinoma). Cytosol CA-19.9 content was determined by enzyme-linked immunoadsorbant assay, and the measurement of this protein was achieved by quantitative assay. Tissue samples were also processed for histological examination.
: we demonstrated that CA-19.9 levels in adenomatous polyps and adenocarcinomas were significantly higher than in the normal mucosa. These levels varied significantly according to polyp size, histological type, and grade of dysplasia. CA-19.9 contents were higher in polyps with a high risk of malignant transformation than in those with a low risk of severe dysplasia. The cut-off value 214 U/mg of protein properly differentiated both types of risk. The area under the receiver operating characteristic (ROC) curves showed that cytosol CA-19.9 levels allow classifying polyps according to their histological features.
: we concluded that the measurement of CA-19.9 content in adenomatous polyps may be useful to classify these tumors and confirm the feasibility to separate adenomas into two groups: low and high risk of malignant change.

Key words: Colorectal adenoma. Colonic polyps. Tissue tumor markers. CA-19.9. Dysplasia grade.

Salces I, Vegh I, Rodríguez-Muñoz S, Colina F, Pérez A, Soto S, Sánchez F, de la Cruz J, Solís-Herruzo JA. Tissue CA-19.9 content in colorectal adenomas and its value in the assesment of dysplasia. Rev Esp Enferm Dig 2004; 96: 246-254.

Recibido: 14-10-03.
Aceptado: 14-10-03.

Correspondencia: Inmaculada Salces Franco. Servicio de Aparato Digestivo. Hospital Universitario 12 de Octubre. Avda. de Andalucía, km. 5,400. 28041 Madrid. Telf.: 913908409. Fax: 913908280. e-mail:



It is well known that colorectal adenomas are tumors with a potential for developing carcinoma over a period of 5 to 15 years, and that this potential is related to the size of polyps, proportion of villous component, and grade of dysplasia (1-6). In some instances, the histological classification of polyps is difficult as these adenomas may contain areas with variable grades of dysplasia (7-10). The feasibility to discriminate groups of adenomas with different risks of malignant transformation could be important when choosing which polyps should be preferently polypectomized, or whether to increase the endoscopic surveillance or to consider an additional treatment (11).

The cytosolic carbohydrate antigen (CA-19.9) is a protein related to the monosyalilated Lewis antigen, which is expressed on the cell membrane and in the cytosol of human colorectal carcinoma as well as in the normal mucosa (12-18). Serum CA-19.9 levels are frequently used as a tumor marker, particularly for colon and pancreas cancer. A number of studies have shown the usefulness of this marker for assessing cancer progression, evaluating radical surgery or detecting recurrence (19-21). However, this tumor marker is often not detectable in the serum of patients with precancerous lesions, early cancer, and occasionally even advanced cancer. The low sensitivity of this tumor marker has been ascribed to a loss of tumor cells' capability to synthesize or release this antigen (20,21). Moreover, its specificity is also low, since high levels of serum CA-19.9 have been detected in the serum of patients with other malignant and non-malignant conditions such as cancer of the liver, gallbladder, pancreas, stomach or breast, as well as pancreatitis, liver diseases or autoimmune diseases. It is to be expected that the measurement of this tumor protein in the tissue may be more sensitive and specific for recognizing a high risk of malignant transformation in colorectal adenomas. The aim of this study was to assess the value of the measurement of tissue CA-19.9 antigen in the classification of polyps according to the risk of malignancy.



This study included 145 patients (97 men and 48 women) who underwent a full colonoscopy. An informed consent was obtained before their inclusion in the study. One hundred and fifty-five colorectal samples were collected endoscopically. In 21 cases the mucosa was normal, and in another 21 samples contained adenocarcioma. In the remaining 113 biopsies the histopathologic study showed adenomatous polyps that were removed from 103 patients. All samples were divided into two pieces; one of them was kept in 10% formol for histological examination, and the remaining piece was frozen in liquid nitrogen and stored at -80 ºC until CA-19.9 cytosol determination (4,22-24).

Determination of CA-19.9 in colonic tissue

Tissue CA-19.9 in the colon mucosa was measured using a microparticle enzimoimmunoassay (MEIA). Results obtained by this technique closely correlated with those recorded using a commercial radioimmunoassay (CA-19.9 RIA-gnost CIS Diagnostic, Madrid. Spain). Samples were thawed and homogenized at 4 ºC with extraction buffer. Homogenates were centrifuged at 106,000 g for 30 minutes, and supernatants were collected for CA-19.9 assay and protein determination. This antigen was measured by a commercial assay (Abbott Cientifica, Madrid, Spain) based on the reaction between the monoclonal antibody 1116-NS-19.9 (12) and the carbohydrate antigen CA-19.9 determinant expressed on the cell surface. Cytosol CA-19.9 levels were expressed as units per milligram of protein (U/mg). Total tissue protein concentrations were determined according to Lowry et al. (25) (Bio-Rad Laboratories, Madrid, Spain).

Histopathologic analysis

Tissue samples were routinely processed and sections were stained with hematoxylin and eosin, periodate-Schiff's reagent (PAS) with and without diastase digestion. Samples were analyzed by two independent pathologists who were unaware of the results of the CA-19.9 determination in tissue. Adenomas were classified according to their histological type (tubular, villous or tubulovillous) and dysplasia grade (mild, moderate, severe or carcinoma in situ).

The diagnosis of mild dysplasia was established when the glands showed elongation or branching, cell nuclei main-tained their basal polarity in the cell, were slightly enlarged, oval, uniform in size, and with inconspicuous nucleoli.

Moderate dysplasia was considered when nuclei lost their basal polarity, became pseudostratified, and contain-ed prominent nucleoli. In these cases glands were more crowded and branched, and contained no goblet cells.

Severe dysplasia was diagnosed when there was an important reduction of interglandular stroma with extreme glandular crowding and irregularity. Moreover, cell nuclei were pleomorphic, stratified with more prominent and numerous nucleoli, and increased nuclear-cytoplasmic ratio. Nuclear membranes were usually irregular and the chromatin pattern was hiperchromatic, vesicular or clumped.

Carcinoma in situ (CIS) was defined as a severe architectural distortion of glands with further cell proliferation within the crypt, loss of polarity, piled-up cells, and growth of glands within glands, resulting in a cribriform appearance or "back to back" pattern. Despite these changes, the basal membrane that surrounded these glands remained intact (26-28).

Statistical analysis

All data are expressed as mean ± standard deviation. Due to the asymmetry and dispersion of CA-19.9 levels in tissue, a logarithmic transformation of these values was performed. An analysis of variance (ANOVA) was applied to establish the significance of differences when all groups of lesions were compared. P<0.05 was considered statistically significant. The statistical performance of absolute antigen values and their logarithmic transformations were similar in every analysis. We also calculated sensitivity (S) and specificity (SP) rates, positive predictive value (PPV), negative predictive value (NPV), diagnostic efficiency (DE), and positive likelihood ratio (PLH) for the different tissue CA19.9 values (29,30). Receiver operating characteristic (ROC) curves was performed to determine the diagnostic efficiency for the different variables and risk groups (31-34). All data were analysed using the statistical program SAS (SAS Inc, Cary, North Carolina 27513, USA).


Tissue CA19.9 levels and diagnostic performance parameters

Tissue CA19.9 values were 12.3±17.3 U/mg in the normal mucosa. These levels were significantly lower (p<0.001) than those found in adenomatous polyps (339±1073 U/mg) or adenocarcinomas (7,859±11,601 U/mg) (Fig. 1). Only in one of the 50 normal mucosa samples (2%) CA-19.9 levels were higher than 50 U/mg, whereas 53.1% of the adenomatous polyps had tissue levels of this antigen below 50 U/mg. This mainly occurred in polyps with mild dysplasia (91.6%), without villous component (93.3%) or of less than 1 cm in size (53.3%). In these groups of polyps, CA19.9 levels ranged between 0.3 and 219 U/mg. Only in one case of adenocarcinoma CA-19.9 concentration was lower than 50 U/mg. The diagnostic performance parameters for the threshold value of 50 U/mg were assessed in the normal mucosa versus the adenomas. Results were: S: 44%; SP: 95%; PPV: 98%; NPV: 24%; EF: 45% and PLH (95% confidence interval): 9.3 (1.9-52.7).

Tissue CA-19.9 levels in relation to polyp characteristics

Size. Tissue CA-19.9 levels in polyps smaller than 1 cm in size were 54 ± 77 U/mg, while in those measuring between 1 and 2 cm these levels rose to 285 ± 1145 U/mg, and to 751± 393 U/mg in polyps with diameters exceeding 2 cm. These differences were statistically significant (p< 0.001) (Table I).

Histologic type
. In tubulovillous and villous polyps, CA-19.9 levels were significantly higher (920 ± 1669 U/mg) (p< 0.001) than in tubular adenomas (139±676 U/mg) (Table I).

Grade of dysplasia. The content of CA-19.9 in polyps increased with the grade of dysplasia. In polyps with mild dysplasia, CA-19.9 levels were 74±123 U/mg, whereas these levels increased to 325±1241 U/mg in polyps with moderate dysplasia and to 951±1731 U/mg in polyps with severe dysplasia. In polyps with CIS, the levels of this antigen were similar to those found in polyps with severe dysplasia (875±897 U/mg). Differences among these four groups of polyps were statistically significant (p<0.001). Nevertheless, no significant differences existed in the tissue levels of CA-19.9 between polyps with mild and moderate dysplasia or between adenomas with severe dysplasia and CIS. On the contrary, A-19.9 levels were significantly higher in polyps with severe dysplasia versus those with moderate dysplasia (p<0.01). The significance of the difference (p<0.001) persisted when polyps were gathered into two groups: one included polyps with mild or moderate dysplasia (195±871 U/mg); the other comprised polyps with severe dysplasia or CIS (933±1561 U/mg) (Table I). These groups were called "low-grade dysplasia" and "high-grade dysplasia", respectively.

CA-19.9 diagnostic performance parameters to assess severe dysplasia

To establish whether the measurement of CA-19.9 levels in polyps can recognize severe dysplasia or CIS, several cut-off levels were chosen. As table II shows, the cut-off value with the highest sensitivity and specificity was 214 U/mg. The areas under the ROC curves for size, villous component and dysplasia grade were 0.66, 0.84 and 0.78, respectively. For polyps with high risk (large size, villous component and severe dysplasia) and low risk of malignant transformation (small, tubular, mild or moderate grade dysplasia), these areas under the ROC curves were 0.84 and 0.81, respectively (Fig. 2).


The present study shows that cytosol CA-19.9 levels are increased in adenomatous polyps and adenocarcinomas (Fig. 1). This finding concurs with those reported by Fischbach and Mössner (19), and Imamura et al. (21), who suggested that tissue antigen measurement might be useful to assess the grade of dysplasia in colorectal adenomas.

CA-19.9 levels were usually under 50 U/mg in the normal mucosa and in polyps with low risk of malignant transformation (small, without villous component, and low grade of dysplasia); therefore, this value allows to differentiate these types of mucosa from adenocarcinoma (PLH: 9.3, SP: 95%, PPV: 98%). However, our study also shows that cytosolic CA-19.9 levels vary widely both in polyps and adenocarcinomas. This finding has also been observed by other authors (20,35). A loss of the capacity of tumor cells to synthesize or release this antigen may be an explanation for these variable levels of tissue CA-19.9. Other possible explanations include the irregular distribution of lesions and the presence of wide necrotic areas within tumors (20).

Our study also shows that there are significant relationships between cytosolic CA-19.9 levels and the size, proportion of villous component and grade of dysplasia in adenomatous polyps. Thus, large polyps with severe dysplasia and more villous component had higher cytosolic CA-19.9 levels than small adenomas with low dysplasia and no villous component. Fischbach and Mössner (19), and Imamura et al. (21) also studied the relationship between tissue CA-19.9 contents and grade of dysplasia in colorectal adenomatous polyps. However, they could not demonstrate any significant relationship between them. The reason for the difference between the results obtained by these authors (21) is not clear, although the number of samples studied was relatively small and the methods used to measure tissue CA-19.9 concentrations were different.

When the CA-19.9 levels were compared in polyps with different grades of dysplasia, we found that there were no significant differences between polyps with mild and moderate dysplasia or polyps with severe dysplasia and CIS. However, differences were significant when CA-19.9 levels in polyps with mild or moderate dysplasia were compared to those in polyps with severe dysplasia or CIS. Thus, as tissue levels of CA-19.9 increase, so do the grade of dysplasia and risk of malignant transformation. It confirmed the usefulness of separating two groups of polyps, which are characterized by dysplasia (low and high grade) and therefore a low and high risk of malignant transformation, as reported by the US National Polyp Study (11).

ROC curves are useful tools to show the quality of information obtained by a specific test (31-34). When the ROC curve for high-grade dysplasia was performed and tissue CA-19.9 contents provided good discrimination (area=0.78), we found that 214 U/mg of CA-19.9 was the threshold value with the highest discrimination potential (S: 63%; SP: 89%; EF: 84%). This value allows a classification of polyps with high-grade dysplasia (severe dysplasia or CIS), and to differentiate them from those with low-grade dysplasia (mild or moderate dysplasia).

We concluded that cytosolic CA-19.9 levels increase steadily from the normal colonic mucosa through colorectal adenoma to adenocarcinoma. The threshold value 214 U/mg allows distinguishing polyps with low potential for malignant transformation from those with a higher risk of malignant transformation. Therefore, the measurement of CA-19.9 content in polyps may be a useful parameter for their classification when histology is conflicting. These results could also be useful in the clinical setting, although endoscopic surveillance may be more frequent for this type of polyps or the consideration of additional therapy.


1. Winawer SJ. Natural history of colorectal cancer. Am J Med 1999; 106:3S-6S; discussion 50S-51S.        [ Links ]

2. Winawer S, Zauber A. The advanced adenoma as the primary target of screening. Gastrointest Endosc Clin N Am 2002; 12: 1-9,v.         [ Links ]

3. Winawer S, Fletcher R, Douglas R, Bond J, Burt R, Ferrucci J, et al. Colorectal cancer screening and surveillance: clinical guidelines and rationale-update based on new evidence. Gastroenterology 2003; 124: 544-60.        [ Links ]

4. Itzkowitz SH, Kim YS. Colonic polyps and polyposis syndromes. En: Feldman M, Scharschmidt BF, Sleisenger MH, eds. Sleisenger and Fordtran's Gastrointestinal and Liver disease. Pathophisiology, Diagnosis, Management. 6th Ed; Vol. II. Philadelphia: WB. Saunders. 1998. p. 1865-905.        [ Links ]

5. Itzkowitz SH. Gastrointestinal adenomatous polyps. Semin Gastrointest Dis 1996; 7: 105-16.         [ Links ]

6. Winawer SJ. Appropriate intervals for surveillance. Gastrointest Endosc 1999; 49: S63-66.        [ Links ]

7. Brown LJ, Smeeton NC, Dixon MF. Assessment of dysplasia in colorectal adenomas: an observer variation and morphometric study. J Clin Pathol 1985; 38: 174-9.        [ Links ]

8. Dixon MF, Brown LJ, Gilmour HM, Price AB, Smeeton NC, Talbot IC, et al. Observer variation in assessment of dysplasia in ulcerative colitis. Histopathology 1988; 13: 385-97.        [ Links ]

9. Jensen P, Krogsgaard M, Christiansen J, Braendstrup O, Johansen A, Olsen J. Observer variability in the assessment of type and dysplasia of colorectal adenomas, analyzed using kappa statistics. Dis Colon Rectum 1995; 38: 195-8.        [ Links ]

10. Rex D, Alikhan M, Cummings O, Ulbright TM. Accuracy of pathologic interpretation of colorectal polyps by general pathologists in community practice. Gastrointest Endosc 1999; 50: 468-74.        [ Links ]

11. Bond JH. Follow-up after polypectomy: Consensus? Eur J Cancer 1995; 31A: 1141-4.        [ Links ]

12. Koprowski H, Steplewski Z, Mitchell K, Herlyn M, Herlyn D, Fuhrer P. Colorectal carcinoma antigens detected by hybridoma antibodies. Somatic Cell Genet 1979; 5: 957-71.        [ Links ]

13. Koprowski H, Herlyn M, Steplewski Z, Sears HF. Specific antigen in serum of patients with colon carcinoma. Science 1981; 212: 53-5.        [ Links ]

14. Magnani JL, Brockhaus M, Smith DF, Ginsburg V, Blaszczyk Mitchell KF, et al. A monosialoganglioside is a monoclonal antibody-defined antigen of colon carcinoma. Science 1981; 212: 55-6.         [ Links ]

15. Koprowski H, Brockhaus M, Blaszczyk M, Magnani J, Steplewski Z, Ginsburg V. Lewis Blood-type may affect the incidence of gastrointestinal cancer. Lancet 1982; 1: 1332-3.        [ Links ]

16. Magnani JL, Nilsson B, Brockhaus M, Zopf D, Steplewski Z, Koprowski H, et al. A monoclonal antibody-defined antigen associated with gastrointestinal cancer is a ganglioside containing sialylated lacto-N-fucopentaose II. J Biol Chem 1982; 257: 14365-9.        [ Links ]

17. Lindholm L, Holmgren J, Svennerholm L, Fredman P, Nilsson O, Persson B, et al. Monoclonal antibodies against gastrointestinal tumour-associated antigens isolated as monosialogangliosides. Int Arch Allergy Appl Immunol 1983; 71: 178-81.        [ Links ]

18. Fukuta S, Magnani JL, Gaur PK, Ginsburg V. Monoclonal antibody CC3C195, which detects cancer-associated antigens in serum, binds to the human Lea blood group antigen and to its sialylated derivative. Arch Biochem Biophys 1987; 255: 214-6.        [ Links ]

19. Filella X, Molina R, Grau JJ, Piqué JM, García-Valdecasas JC, Astudillo E, et al. Prognostic value of CA 19.9 levels in colorectal cancer. Ann Surg 1992; 216: 55-9.        [ Links ]

20. Fischbach W, Mössner J. Tissue concentrations of CEA and CA 19.9 in the carcinogenesis of colorectal carcinoma exemplified by the adenoma-carcinoma sequence. Res Exp Med 1988; 188: 101-14.        [ Links ]

21. Imamura Y, Yasutake K, Yoshimura Y, et al. Contents of tissue CEA and CA 19.9 in colonic polyp and colorectal cancer, and their clinical significance. Gastroenterol Jpn 1990; 25: 186-92.        [ Links ]

22. Konishi F, Morson BC. Pathology of colorectal adenomas: a colonoscopic survey. J Clin Pathol 1982; 35: 830-41.        [ Links ]

23. Maratka Z. Terminology, definitions and diagnostic criteria in digestive endoscopy. With the collaboration of the members of the Terminology Committee of the World Society of Digestive Endoscopy/OMED. Scand J Gastroenterol 1984; 103 (Supl.): 1-74.        [ Links ]

24. Blackstone MO. Colonic polyps. En: Endoscopic interpretation. Normal and pathologic appearances of the gastrointestinal tract. New York: Raven Press, 1984: 429-49.        [ Links ]

25. Lowry OH, Rosebrough NJ, Farr AL. Protein measurement with the Folin-phenol reagent. J Biol Chem 1951; 193: 265-75.        [ Links ]

26. O'Brien MJ, Winner SJ, Zauber AG, Gottlieb LS, Sternberg SS, Diaz B, et al. The National Polyp Study. Patient and polyp characteristics associated with high-grade dysplasia in colorectal adenomas. Gastroenterology 1990; 98: 371-9.        [ Links ]

27. Linares-Santiago E, Gómez-Parra M, Pellicer-Bautista F, Romero-Castro R, Caunedo-Álvarez A, Mendoza-Olivares FJ, et al. The assessment of colonic polyps found via colonoscopy. Gastroenterol Hepatol 1999; 22: 273-8.        [ Links ]

28. Compton C, Henson D, Hutter R, Sobin LH, Bowman HE. Updated protocol for the examination of specimens removed from patients with colorectal carcinoma. A basis for checklists. Arch Pathol Lab Med 1997; 12: 1247-54.        [ Links ]

29. Altman DG, Bland JM. Diagnostic tests 1: sensitivity and specificity. BMJ 1994; 308: 1552.        [ Links ]

30. Altman DG, Bland JM. Diagnostic tests 2: predictive values. BMJ 1994; 309: 102.        [ Links ]

31. Altman DG, Bland JM. Diagnostic tests 3: receiver operating characteristic plots. BMJ 1994; 309: 188.        [ Links ]

32. Zweig MH, Campbell G. Receiver operating characteristic (ROC) plots: a fundamental evaluation tool in clinical medicine. Clin Chem 1993; 39: 561-77.        [ Links ]

33. Altman DG. ROC curves and confidence intervals: getting them right. Heart 2000; 83: 236.        [ Links ]

34. Hanley JA, McNeil BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology 1982; 143: 29-36.        [ Links ]

35. Wagener Ch, Müller-Wallraf R, Nisson S, Groner J, Breuer H. Localization and concentration of carcinoembryonic antigen (CEA) in gastrointestinal tumors: correlation with CEA levels in plasma. J Natl Cancer Inst 1981; 67: 539-47.        [ Links ]

Creative Commons License Todo el contenido de esta revista, excepto dónde está identificado, está bajo una Licencia Creative Commons